Loading [Contrib]/a11y/accessibility-menu.js
Research article Special Issues

Automated multi-class brain tumor types detection by extracting RICA based features and employing machine learning techniques

  • Received: 20 November 2020 Accepted: 24 February 2021 Published: 28 March 2021
  • Among the other cancer types, the brain tumor is one the leading cause of cancer across globe. If the tumor is properly identified at an earlier stage, then the chances of the survival can be increased. To categorize the brain tumor there are several factors including texture, type and location of brain tumor. We proposed a novel reconstruction independent component analysis (RICA) feature extraction method to detect multi-class brain tumor types (pituitary, meningioma, and glioma). We then employed the robust machine learning techniques as support vector machine (SVM) with quadratic and linear kernels and linear discriminant analysis (LDA). For training and testing of the data validation, a 10-fold cross validation was employed. For the multi-class classification, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and AUC were, respectively, 97.78%, 100%, 100%, 99.07, 99.34% and 0.9892 to detect pituitary using SVM Cubic followed by meningioma with accuracy (96.96%0, AUC (0.9348) and glioma with accuracy (95.88%), AUC (0.9635). The findings indicates that RICA feature based proposed methodology has more potential to detect the multiclass brain tumor types for improving diagnostic efficiency and can further improve the prediction accuracy to achieve the clinical outcomes.

    Citation: Sadia Anjum, Lal Hussain, Mushtaq Ali, Adeel Ahmed Abbasi, Tim Q. Duong. Automated multi-class brain tumor types detection by extracting RICA based features and employing machine learning techniques[J]. Mathematical Biosciences and Engineering, 2021, 18(3): 2882-2908. doi: 10.3934/mbe.2021146

    Related Papers:

    [1] Conrad Omonhinmin, Enameguono Olomukoro, Ayodeji Ayoola, Evans Egwim . Utilization of Moringa oleifera oil for biodiesel production: A systematic review. AIMS Energy, 2020, 8(1): 102-121. doi: 10.3934/energy.2020.1.102
    [2] Douglas Faria, Fernando Santos, Grazielle Machado, Rogério Lourega, Paulo Eichler, Guilherme de Souza, Jeane Lima . Extraction of radish seed oil (Raphanus sativus L.) and evaluation of its potential in biodiesel production. AIMS Energy, 2018, 6(4): 551-565. doi: 10.3934/energy.2018.4.551
    [3] Maria del Pilar Rodriguez, Ryszard Brzezinski, Nathalie Faucheux, Michèle Heitz . Enzymatic transesterification of lipids from microalgae into biodiesel: a review. AIMS Energy, 2016, 4(6): 817-855. doi: 10.3934/energy.2016.6.817
    [4] Sandra M. Damasceno, Vanny Ferraz, David L. Nelson, José D. Fabris . Selective adsorption of fatty acid methyl esters onto a commercial molecular sieve or activated charcoal prepared from the Acrocomia aculeata cake remaining from press-extracting the fruit kernel oil. AIMS Energy, 2018, 6(5): 801-809. doi: 10.3934/energy.2018.5.801
    [5] Geovanna Cristina Zaro, Paulo Henrique Caramori, Cíntia Sorane Good Kitzberger, Fernanda Aparecida Sales, Sergio Luiz Colucci de Carvalho, Cássio Egidio Cavenaghi Prete . Phenological cycle and physicochemical characteristics of avocado cultivars in subtropical conditions. AIMS Energy, 2017, 5(3): 517-528. doi: 10.3934/energy.2017.3.517
    [6] Shemelis Nigatu Gebremariam, Jorge Mario Marchetti . Biodiesel production technologies: review. AIMS Energy, 2017, 5(3): 425-457. doi: 10.3934/energy.2017.3.425
    [7] Dejene Beyene, Dejene Bekele, Bezu Abera . Biodiesel from blended microalgae and waste cooking oils: Optimization, characterization, and fuel quality studies. AIMS Energy, 2024, 12(2): 408-438. doi: 10.3934/energy.2024019
    [8] Fitriani Tupa R. Silalahi, Togar M. Simatupang, Manahan P. Siallagan . A system dynamics approach to biodiesel fund management in Indonesia. AIMS Energy, 2020, 8(6): 1173-1198. doi: 10.3934/energy.2020.6.1173
    [9] Hussein A. Mahmood, Ali O. Al-Sulttani, Hayder A. Alrazen, Osam H. Attia . The impact of different compression ratios on emissions, and combustion characteristics of a biodiesel engine. AIMS Energy, 2024, 12(5): 924-945. doi: 10.3934/energy.2024043
    [10] Xianhui Zhao, Lin Wei, James Julson . First stage of bio-jet fuel production: non-food sunflower oil extraction using cold press method. AIMS Energy, 2014, 2(2): 193-209. doi: 10.3934/energy.2014.2.193
  • Among the other cancer types, the brain tumor is one the leading cause of cancer across globe. If the tumor is properly identified at an earlier stage, then the chances of the survival can be increased. To categorize the brain tumor there are several factors including texture, type and location of brain tumor. We proposed a novel reconstruction independent component analysis (RICA) feature extraction method to detect multi-class brain tumor types (pituitary, meningioma, and glioma). We then employed the robust machine learning techniques as support vector machine (SVM) with quadratic and linear kernels and linear discriminant analysis (LDA). For training and testing of the data validation, a 10-fold cross validation was employed. For the multi-class classification, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and AUC were, respectively, 97.78%, 100%, 100%, 99.07, 99.34% and 0.9892 to detect pituitary using SVM Cubic followed by meningioma with accuracy (96.96%0, AUC (0.9348) and glioma with accuracy (95.88%), AUC (0.9635). The findings indicates that RICA feature based proposed methodology has more potential to detect the multiclass brain tumor types for improving diagnostic efficiency and can further improve the prediction accuracy to achieve the clinical outcomes.



    Abbreviation List

    AEOE   Aqueous enzymatic oil extraction

    ASE   Accelerated solvent extraction

    BP   British petroleum

    FAME   Fatty acid methyl esters

    FFA   Free fatty acid

    IRAR   Infrared radiation assisted reactor

    L.   Linnaeus

    MAAEE   Microwave-assisted aqueous enzymatic extraction

    MAE   Microwave-assisted extraction

    PSE   Pressurized solvent extraction

    SFE   Supercritical fluid extraction

    TAG   Triacylglycerol

    UAE   Ultrasound-assisted extraction


    1. Introduction

    Energy demand is expected to increase due to rapid population growth, expanding urbanization and better living standards [1]. Fossil fuels remain the dominant source of energy [2] though it is non-renewable and has negative impact on global climate [3]. According to BP's Energy Outlook to 2035 [2], world energy consumption is projected to increases by 34% between 2014 and 2035, and fossil fuels remain the dominant source of energy (accounting for almost 80%) powering the global economy in 2035 (down from 86% in 2014). The transport sector, which heavily depends on oil-derived liquid products such as gasoline and diesel, globally occupies the third place when total energy consumption and greenhouse gas (GHG) emissions are considered (after the industry and the building sectors). This consumption level is predicted to increase by 60% by 2030 [4].

    Rapid growth in both global energy demand and carbon dioxide emissions associated with the use of fossil fuels has driven the search for alternative energy sources which are renewable and have a lower environmental impact [5,6]. Thus, it has become apparent that biodiesel is destined to make a substantial contribution to the future energy demands of domestic and industrial economies [6]. Biodiesel is produced from vegetable oil or animal fat reacts in the presence of a catalyst (usually a base) with an alcohol (usually methanol) to give the corresponding alkyl esters (for methanol, fatty acid methyl esters) [7]. Biodiesel is non-toxic, biodegradable and a portable fuel produced from renewable sources [3,8] and it is one of the technically and economically feasible options to tackle the fast depletion of fossil fuels and environmental pollution [1]. The other benefit of biodiesel fuel is that it can be used in any mixture with petro diesel fuel, as it has very similar characteristics [3].

    The potential feedstocks for biodiesel production are edible (first generation feedstocks) and non-edible vegetable oils (second generation feedstocks), wasted oils and animal fats [9] First-generation biofuels are directly related to a biomass that is generally edible, and are usually produced from edible oils, such as soybeans, palm oil, sunflower, safflower, rapeseed, coconut and peanut [4,10]. Second-generation biofuels are fuels that are produced from a wide array of different feedstock, ranging from lignocellulosic feedstocks to municipal solid wastes. Third-generation biofuels are related to algae which have been considered as emerging non-edible oil sources of growing interest because of their high oil content and rapid biomass production [10,11,12] but could also to a certain extent be linked to utilization of CO2 as feedstock [10]. However, the first generation biofuels seems to create some skepticism to scientists. There are concerns about environmental impacts and carbon balances, which sets limits in the increasing production of biofuels of first generation. The main disadvantage of first generation biofuels is the food-versus-fuel debate, one of the reasons for rising food prices is due to the increase in the production of these fuels [9,13,14]. Therefore, non-edible biodiesels feedstocks get great attention to overcome the problem that occurs due to continuous utilization of edible oils for biodiesel [13].

    In the different literature, various biodiesel feedstocks: edible oils, non-edible oils, animal fats, waste oils and algal biomass and methods of biodiesel production from these feedstocks were well described and reviewed. However, the preparation of different feedstocks for oil extraction, oil extraction methods from different feedstocks, advantages and disadvantages of the extraction methods and ways to improve them are, to our knowledge, not yet well reviewed. Thus, the aim of this review is to identify the major biodiesel feedstocks, oil extraction and separation methods, the advantages and disadvantages of various oil extraction methods, particularly that of non-edible oils, and suggest how to optimize the appropriate method (s) to enhance the sustainability of biodiesel production and utilization.


    2. Biodiesel and Its Feedstock

    Biodiesel is defined as the mono-alkyl ester of long chain fatty acids derived from renewable lipid feedstock such as vegetable oils or animal fats [15]. Biodiesel is a non-toxic, biodegradable and renewable fuel that can be produced from a range of organic feedstock including fresh or waste vegetable oils, animal fats, and oilseed plants [16] (the reaction for biodiesel formation is shown in Figure 1).

    Figure 1. Transesterification reaction for biodiesel production [17,18].

    The major components of plant oils and animal fats are triacylglycerol (TAGs); the esters of fatty acids and glycerol. The TAGs, also known as triglycerides, consists of different fatty acid composition which influences both physical and chemical properties of plant oils and animal fats [15,18,19]. There are two kinds of fatty acids: saturated fatty acids containing carbon-carbon single bond, and unsaturated fatty acids which include one or more carbon-carbon double bond. The major components of biodiesel are straight fatty acid chain and the common fatty acids are palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3). The other fatty acids which are also present in several plant oils include myristic acid (C14:0), palmitoleic acid (C16:1), arachidic acid (C20:0), and erucic acid (C22:1) [11,18,19]. According to Sajjadi et al. [17], physico-chemical properties of oils from different sources differ, and it is noteworthy that although some oils may be extracted from a unique root, their compositions are significantly dependent on the main parts from which the oil is extracted.


    2.1. Different types of oils

    Globally, there are more than 350 oil-bearing crops identified as potential sources for biodiesel production [13,17]. The availability of wide range of biodiesel feedstocks is one of the most significant factors that enables the sustainable production of biodiesel [20,21,22]. According to Avhad and Marchetti [18], satisfactory replacement of petroleum diesel with biodiesel depends on two basic requirements: first is its easy availability and environmentally acceptability, and the second is being economically reasonable. Availability of feedstock for producing biodiesel depends on the regional climate, geographical locations, local soil conditions and agricultural practices of any country [13].

    From the literature, it has been found that feedstock alone represents about 75% of the overall biodiesel production cost [13,23,24] as presented in Figure 2. Therefore, minimizing the cost of biodiesel production has been the main agenda for biodiesel producers in order to be competitive with petroleum-derived diesel [25]. Hence, it is crucial to employ inexpensive feedstocks to replace expensive refined oils [4,13]. Using low-cost triglyceride sources such as waste cooking oil and animal fats is also important to minimizing the total cost as these wastes are three times cheaper than refined oils, and are abundantly available [25].

    Figure 2. General cost breakdown for production of biodiesel [13,23,24].

    Feedstocks of biodiesel can be divided into four main categories: edible vegetable oil, non-edible oils, waste or recycled oils, and animal fats [13,18,23,26,27,28]. Accordingly, some forms of plant oils, animal fats, and other feedstocks that are used for producing biodiesel are listed in Table 1.

    Table 1. Main feedstocks of biodiesel [18,20,29,30,31,32,33,34,35,36].
    Edible oils Non-edible oils Animal fats Other sources
    Barley Abutilon muticum Beef tallow Cyanobacteria
    Canola Aleurites moluccana Chicken fat Bacteria
    Coconut Camelina (Camelina Sativa) Fish oil Cooking oil
    Corn Coffee ground (Coffea arabica) Pork lard Fungi
    Groundnut Cotton seed (Gossypium hirsutum) Poultry fat Latexes
    Palm and palm kernel (Elaeis guineensis) Croton megalocarpus Waste salmon Microalgae (Chlorellavulgaris)
    Peanut Cynara cardunculus Miscanthus
    Pumpkin seed Jatropha curcas Pomace oil
    Rapeseed (Brassica napus L.) Jojoba (Simmondsia chinensis) Poplar
    Rice bran oil (Oryza sativum) Karanja or honge (Pongamia pinnata) Soapstocks
    Safflower (Carthamus tinctorius) Mahua (Madhuca indica) Switchgrass
    Sesame (Sesamum indicum L.) Moringa (Moringa oleifera) Tall oil
    Sorghum Nagchampa (Calophyllum inophyllum) Tarpenes
    Soybeans (Glycine max) Neem (Azadirachta indica)
    Sunflower (Helianthus annuus) Pachira glabra
    Wheat Passion seed (Passiflora edulis)
    Pongamia (Pongamia pinnata)
    Rubber seed tree (Hevca brasiliensis)
    Terminalia belerica
    Tobacco seed
     | Show Table
    DownLoad: CSV

    2.1.1. Edible plant oils

    Edible oils resources such as soybeans, palm oil, sunflower, safflower, rapeseed, coconut and peanut are considered as the first generation biodiesel feedstocks because they were the first crops to be used for biodiesel production [13]. Edible oil contents of seeds and kernels of some plants are shown in Table 2. Currently, more than 95% of the world biodiesel is produced from edible oils such as rapeseed (84%), sunflower oil (13%), palm oil (1%), soybean oil and others (2%) [4,13]. Plantations of these feedstock plants have been also well established in many countries around the world such as Malaysia, USA and Germany [13]. However, continuous large-scale usage of edible plant oils for biodiesel production raises many concerns such as food versus fuel crisis and major environmental problems such as deforestation and destruction of vital soil resources, conversion of much available farm lands to oil bearing plants [13,14].

    Table 2. Species name and oil content of edible and non-edible plant [6,11,12,13,30,37,38,39,40,41,42,43,44,45,46,47,48,49,50].
    Type of oil Common name Species name Oil content of seed/kernel (wt%) Reference
    Seed Kernel
    Edible Coconut Cocos Nucifera L. 63–65 63.1 (± 2.8) [6,38]
    Corn Zea mays 24.44 - [39]
    Hemp seed Cannabis Sativa L. 22–38 - [40]
    Mustard seed Brassica nigra 33 - [41]
    Olive Olea europaea 45–70 - [37]
    Palm Elaeis guineensis 30–60 - [6]
    Peanut Arachis hypogea L. 45–55 47–61 [6,37]
    Pumpkin seed Cucurbita maxima 31.5 43.69 (± 3.92) [42,43]
    Rapeseed Brassica napus 38–46 - [6]
    Rice bran Oryza sativa 15–23 - [37]
    Safflower seed Carthamus tinctorius 35 - [44]
    Sesame seed Sesamum indicum 58 - [45]
    Soybean Glycine max 18–20 - [46]
    Sunflower Helianthus annuus 25–35 50 [37,47]
    Non-edible Castor Ricinuscommunis L. 45–50 - [30]
    Cottonseed Gossypium hirsutum L. 18–25 31.42 [37,48]
    Desert date Balanites aegyptiaca 45–50 36–47 [12]
    Jatropha Jatropha curcas L. 20–60 40–60 [12,30,49]
    Jojoba Simmondisa chincnsis 45–50 - [37]
    Karanja Pongamia pinnata 30–40 30–50 [30]
    Linseed Linum usitatissimum 35–45 - [30]
    Mahua Madhuca indica 35–40 50 [30]
    Neem Azadirachta indica 20–30 25–45 [30]
    Polanga Calophyllum inophyllum 65 22 [12]
    Caster Ricinus communis 45–50 - [11]
    Rubber seed Hevea brasiliensis 40–60 40–50 [12]
    Tobacco Nicotiana tabacum L. 30–43 - [37]
    Nicotiana tabacum 36–41 17 [11,12]
    Zanthoxylum bungeanum 24–28 25 [12]
    Tung Vernicia montana 16–18 - [37]
    Ethiopian mustard Brassica carinata 42 2.2–10.8 [12]
    Sea mango Cerbera odollam 54 6.4 [12]
    Croton oil plant Croton tiglium 30–45 50–60 [50]
     | Show Table
    DownLoad: CSV

    The prices of vegetable oil have also increased dramatically in the last few decades and this will affect the economic viability of biodiesel industry [13,14,51]. Furthermore, the use of such edible oils to produce biodiesel is not feasible in the long term due to the growing gap between demand and supply [13]. Thus, the current use of the food-grade plant oils as a feedstock for producing biodiesel are considered to be not worthy and stipulates search for relatively less expensive resources [13,18].

    The average fatty acid composition of different edible vegetable oils are shown in Table 3. The dominant fatty acids of edible oils are oleic acid (C18:1), linoleic acid (C18:2), palmitic acid (C16:0) and staeric acid (C18:0). The fatty acid composition of edible oils from different plants seeds differ. For example, caprylic acid, which is the lightest compound is only available in wheat grain (11.4 wt%) and coconut oils (8.45 wt%) [17]. According to Sajjadi et al. [17], generally is assumed that the compositions of fatty acids compositional profiles do not change during the conversion of the feedstocks to fuel via transesterification and thus, greatly affect the quality of biodiesel to be produced.

    Table 3. Comparison of the fatty acid composition of the selected edible oils.
    Source Fatty Acids Composition Reference
    C14:0 Myristic acid C16:0 Palmitic acid C16:1 Palmitoleic acid C18:0 Stearic acid C18:1 Oleic acid C18:2 Linoleic acid C18:3 Linolenic acid C20:0 Arachidic acid C22:0 Behenic acid C20:1 Gadoleic acid C22:1 Erucic acid C24:0 Lignoceric acid C8:0 Capryli acid
    Waste
    coconut oil
    0.50 21.40 0.20 3.00 27.50 47.40 - - - - - - 8.45 [52]
    Corn - - 11.67 1.85 25.16 60.60 0.48 0.24 - - - - - [15]
    Hempseed - 6.0–8.5 - 2.5–3.0 12.0–15.0 52.0–56.0 - 0.5–0.8 - - - - - [53]
    Mustard seed 0.05 5.54 0.21 1.51 8.83 10.79 20.98 1.21 1.09 5.27 37.71 1.68 - [41]
    Olive - 11.60 1.00 3.10 75.00 7.80 0.60 0.30 0.10 - - 0.50 - [54]
    Palm 0.70 36.70 0.10 6.60 46.10 8.60 0.30 0.40 0.10 0.20 - 0.10 - [54]
    Peanut 0.20 8.0 - 1.80 53.30 28.40 0.30 0.90 3.00 2.40 - 1.80 - [54]
    Pumpkin seed - 13.80 - 11.20 29.50 45.5 - - - - - - - [42]
    Rapeseed - - 3.49 0.85 64.40 22.30 8.23 - - - - - - [15]
    Rice bran - 22.00 - 3.00 38.00 35.00 - - - - - - - [55]
    Safflower seed - 11.07 (± 0.10) - 4.37 (± 0.10) 12.76 (± 0.22) 69.65 (± 0.24) 0.49 (± 1.15) 0.78 (± 0.05) 0.59 (± 0.09) - - 0.29 (± 0.13) [56]
    Sesame - 9.80 (± 0.21) - 6.3 (± 0.15) 41.82 (± 0.91) 40.50 (± 1.01) 0.32 (± 0.01) 0.67 (± 0.03) - - - - - [57]
    Sunflower - 16.29 (± 0.54) - 6.66 22.70 (± 0.07) 44.13 (± 0.60) 8.97 (± 0.52) 0.62 (± 70.11) 0.63 (± 70.02) - - - - [55]
    Soybean - 6.14 0.09 4.11 34.30 51.17 2.23 0.17 0.41 - 0.53 - - [58]
    Wheat grain 0.13 17.71 0.2 0.78 16.5 56 2.9 - - - - - 11.4 [17]
     | Show Table
    DownLoad: CSV

    One of the possible solutions to reduce the utilization of the edible oil for biodiesel production is by exploiting non-edible oils. They got great attention as the plants from which these oils obtained are easily available in many parts of the world [6,13,59]. These plants can grow on wastelands that are not suitable for food crops, eliminate competition for food, reduce deforestation rate, and their oils are very economical compared to edible oils [13].


    2.1.2. Non-edible plant oils

    Non-edible plant oils which are known as the second generation feedstocks can be considered as promising substitutions for traditional edible food crops for the production of biodiesel [6]. Recently, these oils have gained enormous attention as a new generation feedstock because of their high oil content, easy availability, and having the advantage that it could be grown on lands which are not suitable for agriculture [6,13]. Non-edible oil bearing plants could also be grown with less intensive attention; thus, reducing the cost of cultivation [6,12,13,18]. Therefore, production of biodiesel from non-edible oils is an effective way to overcome the associated problems with edible oils [6]. Some of the main and most investigated non-edible plant oils for biodiesel production include jatropha seed oil [32,36], karanja oil [33], jojoba oil [34], linseed oil [35], cottonseed oil [60], amongst others (Table 1).

    During selection of any feedstock as a biodiesel source, the amount of oil that can be obtained from the seeds or kernel is an important parameter. Estimated oil contents of seed and kernel of some non-edible vegetable oil were shown in Table 2 [6,12]. Moreover, fatty acid composition is an important characteristic of biodiesel feedstock as it determines the efficiency of process to produce biodiesel. It has been observed that the percentage and type of fatty acid compositions depends mainly on the plant species as well as their growth conditions [6].

    The fatty acid composition and distribution of non-edible oils are generally aliphatic compounds with a carboxyl group at the end of a straight chain [4]. Ong et al. [19] reported that the presence of fatty acid compositions has interfered fuel properties and quality of biodiesel. It has also been found that the biodiesel with a high level of methyl oleate (mono unsaturated fatty acid) might have excellent characteristics in ignition quality, fuel stability and flow properties at low temperature [19,61].

    Generally, non-edible oil is composed of a high number of double carbon chain (polyunsaturated acid) which indicate that the these oil group has a greater degree of unsaturated fatty acid than saturated carbon chain [19,62]. Moreover, it was reported that cetane number, heat of combustion, melting point, and viscosity of neat fatty compounds increase with increasing chain length and decrease with increasing unsaturation [62,63] of the fatty acid methyl esters (FAME) molecule. Therefore, structural fatty acid composition will affect the physico-chemical properties of biodiesel such as cetane number, cold flow properties, heat of combustion and viscosity [6,61,62]. Fatty acid compositions of various non-edible oils that were found to be suitable for production of biodiesel are shown in Table 4.

    Table 4. Comparison of the fatty acid composition of the selected non-edible plant oils [4,17,30,32,34,37,64,65,66,67,68,69,70].
    Feed stocks Fatty Acids Reference
    C14:0 Myristic acid C16:0 Palmitic acid C16:1 Palmitoleic acid C18:0 Stearic acid C18:1 Oleic acid C18:2 Linoleic acid 18:3 Linolenic acid C20:0 Arachidic acid C22:0 Behenic acid C20:1 Gondoic acid C22:1 Erucic acid C18:1 Riconoleic acid
    Caster seed - 1.00 - - 3.00 5.00 1.00 - - - - 89.00 [64]
    Cottonseed 1.00 25.80 0.60 2.5 16.4 (± 0.8) 51.50 0.20 0.20 0.20 - - - [65]
    Desertdate kernel - 15.40 (± 0.26) - 19.01 (± 0.29) 25.74 (± 0.35) 39.85 (± 0.48) - - - - - - [66]
    Jatropha - 15.20 0.70 6.80 44.60 32.20 - 0.40 - - - - [32,34]
    Jojoba - 1.20 - - 10.70 - - 9.10 - 59.50 12.30 - [67]
    Karanja - 11.65 - 2.4–8.9 51.59 16.46 2.65 - - - - - [68]
    Linseed - 5.10 0.30 2.5 18.90 18.10 55.10 - - - - - [69]
    Mahua - 17.80 - 14.00 46.30 17.90 - - - 1.7 - - [70]
    Moringa - 7.60 1.40 5.5 66.60 8.10 0.20 5.80 - - - - [71]
    Neem 0.2–0.26 14.9 0.1 20.6 43.9 17.9 0.4 1.6 0.3 - - - [72]
    Polonga - 12.01 - 12.95 34.09 38.26 0.30 - - - [68]
    Rubber seed 2.2 10.2 - 8.7 24.6 39.6 16.3 - - - - - [73]
    Tobaco 0.14 8.46 - 3.38 11.24 75.58 1.14 - - - - - [74]
    Tung - 4.00 - 1.00 8.00 4.00 3.00 - - - - - [37]
     | Show Table
    DownLoad: CSV

    2.1.3. Waste oils and animal fats

    The residual obtained after using oil for the cooking purposes is generally discarded with no further application [18]. Over the last few years, waste cooking oil has been considered as a possible feedstock for biodiesel production due its low cost, and as its biofuel was found to fulfill the requirements specified by European standard for biodiesel (EN) and American Society for Testing and Materials (ASTM) standards [75]. However, waste oil is highly impure consisting mainly of high free fatty acid (FFA), and thus, could be categorized in two groups based on its FFA content: the yellow grease (FFA < 15%), and the brown grease (FFA > 15%). These oils after the filtration and purification processes could be used for biodiesel production [18].

    Animal fats such as tallow [76], chicken fat [77], lard [78] and yellow grease [79] are also considered as feedstocks. According to Adewale et al. [80], animal fat wastes are low cost, mitigate environmental damage and increase the quality of the resultant biodiesel fuel. However, it has been reported that these may not be plentiful enough to satisfy the global energy demand. Moreover, biodiesel derived from animal fats has a relatively poor performance in cold weather. Furthermore, the transesterification process is difficult for some types of fats due to the presence of a high amount of saturated fatty acids. [4,13].


    2.1.4. Algae as biodiesel feedstocks

    The amounts of oily crops, both edible and non-edible, animal fats and waste cooking oils are limited, so it is unlikely to provide worldwide biodiesel production demand. The search for other renewable sources is needed to provide the required amount of oily feedstocks. In recent years a high interest towards producing biodiesel from microalgae has been developed. The advantages of using microalgae for biodiesel production are: much higher biomass productivities than land plants, some species can accumulate up to 20–50% triacylglycerol, no agricultural land is required to grow the biomass and they required only sunlight and a few simple and cheap nutrients [81].


    3. Oil Extraction Methods

    One of the important steps in the production of biodiesel is oil extraction, and different methods and techniques of oil extraction are in use [4,12,13]. Preparation of feedstocks and various oil extraction methods are discussed in the following parts.


    3.1. Feedstock preparation

    The pre-requisite for oil extraction is seed preparation [4,13,82]. The preparation of seeds involves removal of outer layers of the fruit to expose the kernels or seeds, and its drying to reduce moisture content [82]. The seeds are separated from fruits, and the fruits that do not dehisce are cracked open manually. The separated seeds or kernels are sieved, cleaned and stored at room temperature [13].

    According to Atabani et al. [13,82] seeds can be either dried in the oven or sun dried to appropriate moisture. The kernels or seeds have to be prepared in such a way that they contain optimum moisture content for high oil extraction. For instance, Jahirul et al. [82] has found that seed kernel of beauty leaf (C. inophyllum) prepared to 15% moisture content provided the highest oil yields in both mechanical and solvent extraction methods. The drying process should be checked very carefully by weighing the trays several times in a day whenever possible and after reaching the desired dryness; the trays are stored in a refrigerated room [4]. Mechanical expellers or presses can be fed with either whole seeds or kernels or a mix of both, but common practice is to use seeds only. However, for chemical extraction only kernels are employed [83].


    3.2. Extraction methods

    After preparation, the raw material is ready for oil extraction. There are three main methods that have been identified for oil extraction: (ⅰ) mechanical extraction, (ⅱ) chemical or solvent extraction, and (ⅲ) enzymatic extraction [4,6,13]. Moreover, accelerated solvent extraction (ASE), supercritical fluid extraction (SFE) as well as microwave-assisted extraction (MAE) methods are frequently used [4]; however, they are not as common or well known as the first three mentioned alternatives

    It has been observed that mechanical pressing and solvent extraction are the most commonly used methods for commercial oil extraction [6]. According to Atabani et al. [13], the main products during oil extraction are the crude oil, and the important by-products are such as seeds or kernel cakes. Seed cakes can be used as fertilizers for soil enrichment [6], feed for poultry, fish and swine, and some oil cakes have also application in fermentation and biotechnological processes [84].


    3.2.1. Mechanical oil extraction

    Mechanical press oil extraction is the most conventional technique. A manual ram press or an engine driven screw press can be used [4]. Jahirul et al. [82] and Bhuiya et al. [85] used a Mini 40 screw press to extract oil from beauty leaf kernels (C. inophyllum). It has been found that engine driven screw press can extract 68–80% of the available oil while the ram presses only achieved 60–65%. Oil extraction efficiencies calculated from data reported in more recent studies are found to generally correspond to these ranges, although the efficiency range of engine driven screw presses can be broadened to 70–80% [4,6,13]. This broader difference is due to the fact that seeds can be subjected to a different number of extractions through the expeller [82,85]. Calculated oil yields (% of contained oil) of mechanical extraction method is presented in Table 5.

    Table 5. Calculated oil yields (% of contained oil) of mechanical extraction methods [6,82,83,86].
    Press type Oil yield (%) Necessary treatment
    Engine driven screw press 68.0 Filtration and degumming
    80.0
    79.0
    Ram press 62.5
     | Show Table
    DownLoad: CSV

    The oil extracted by mechanical presses needs further treatment of filtration and degumming in order to produce a more pure raw material [6,87]. Another problem associated with conventional mechanical presses is that the design of mechanical extractor is suited for some seeds, and therefore, the oil yield is affected if that mechanical extractor is used for other seeds [4,6,13,87]. It has been also found that pretreatment of seeds before applying mechanical extractor increases the amount of oil recovery [6,83]. For instance, by cooking jatropha seeds in water for one hour at 70 ℃ and using screw pressing, Beerens [88] obtained oil yield of 89% after single pass and 91% after dual pass compared to 79% and 87% oil yield recovery of untreated seeds, respectively. Therefore, several other methods have been proposed recently for oil extraction such as solvent extraction, enzymatic extraction and microwave assisted techniques in order to improve the oil extraction yield.


    3.2.2. Solvent oil extraction (chemical extraction)

    Solvent extraction is the process in which the oil is removed from a solid by means of a liquid solvent, it is also known as leaching [4]. The chemical extraction using n-hexane method results in the highest oil yield which makes it the most commonly used solvent [4,13]. Jahirul et al. [82] has used n-hexane to extract the oil from Australian native beauty leaf seeds (Calophyllum inophyllum), although the cost of oil extraction technique by mechanical screw press is low it is ineffective due to relatively lower oil yields. On the contrary, the chemical oil extraction method was found to be very effective because of high oil yield and for its consistent performance.

    It has been observed that there are many factors affecting the rate of solvent extraction such as particle size, the type of solvent used, temperature and agitation speed [6,13]. The solvent has to be selected in such a way that it would be a good selective solvent and its viscosity would be sufficiently low to circulate freely. Sayyar et al. [89] extracted J. curcas oil by n-hexane and petroleum ether and found that the extraction yield with n-hexane to be about 1.3% more than that of petroleum ether (47.3% and 46.0% wt, respectively) under similar conditions. The authors recognized n-hexane as a more preferable solvent for extraction of jatropha oil as compared to petroleum ether. In the extraction of olive oil using organic solvents like hexane, ethanol, petroleum ether, isopropyl alcohol and carbon tetrachloride by a Soxhlet extractor, Banat et al. [90] did also obtain the highest oil yield (12.7%) by n-hexane. However, it has been observed that this method consumes much more time compared to other techniques. The solvent extraction is only economical attractive at a large-scale of production (more than 50 ton biodiesel per day) as reported [13]. In addition, n-hexane solvent extraction has a negative environmental impact because of the wastewater generation, higher specific energy consumption and higher emissions of volatile organic compounds and human health impacts [6]. According to Achten et al. [83] and Mahanta and Shrivastava [91], there are three other types of solvent extraction technique: hot water extraction, soxhlet extraction and ultrasonication technique that could be use instead of hexane solvent extraction.

    Jahirul et al. [82] reported that in oil extraction from beauty leaf seeds(Calophyllum inophyllum) by mechanical method (using the screw press) and chemical extraction (using hexane as a solvent), each method has advantages and disadvantages. The advantages and disadvantages of oil extraction by mechanical extraction and chemical extraction from beauty leaf seeds is presented in Table 6.

    Table 6. Advantages and disadvantages of mechanical and chemical oil extraction methods for beauty leaf seeds [82].
    Mechanical Extraction Chemical Extraction
    Advantages Disadvantages Advantages Disadvantages
    √ Virgin oil is more sought after
    √ No potential for solvent contamination
    √ Relatively inexpensive after initial capital costs
    √ Minor consumables cost
    · Generally ineffective for processing Beauty Leaf seed
    · Time and labor intensive
    · Relatively low oil yields
    · Operators require experience to achieve best results
    · High dependence on kernel moisture content
    √ Repeatable and reproducible results and process
    √ High oil yields
    √ Relatively simple and quick
    √ Hexane can be recovered and reused, reducing cost significantly
    · Less sought after than virgin oil
    · Potential for solvent contamination
    · Safety issues and environmental concerns regarding the use of hexane
    · Very costly if the hexane cannot be recovered
     | Show Table
    DownLoad: CSV

    3.2.3. Accelerated solvent extraction (ASE)

    Accelerated solvent extraction (ASE) is also referred to as pressurized solvent extraction (PSE) is another modern oil extraction technique which uses organic and/or aqueous solvents at elevated temperatures and pressures [4]. It has been observed that high temperature accelerates the extraction rate, while elevated pressure prevents boiling at temperatures above the normal boiling point of the solvent.

    Khattab and Zeitoun [92] have extracted oil of flaxseed by different methods by supercritical fluid extraction (SFE), accelerated solvent extraction (ASE) and conventional solvent extraction (SE) and found the highest oil yield (42.40%) by SE using n-hexane which did not differ significantly from the one obtained by accelerated solvent extraction ASE in terms of oil quantity (41.90%) and their physicochemical properties and fatty acid profiles. The supercritical fluid extraction (SFE), however, showed significantly lower oil yield (36.49%) in this particular oil extraction from flaxseed. Sarip et al. [93] have also extracted crude palm oil from palm mesocarp by using hot compressed water extraction method and obtained 70 ± 0.5% of the oil with averaged free fatty acid of 0.81 ± 0.08%. Moreover, it was also reported that ASE has been used for the extraction of different materials including wheat germ [94] and flaxseed hulls [95]. In ASE, time as well as solvent consumption is significantly reduced compared to the other solvent extraction techniques [92,94].


    3.2.4. Enzymatic oil extraction

    Aqueous enzymatic oil extraction (AEOE) method is a promising technique for extraction of oil from plant materials [96,97]. In this method, enzymes should be used to extract oil from crushed seeds [91]. Aqueous enzymatic oil extraction can also be used in combination with other methods of oil extraction. For instance, Shah et al. [97] used a combination of ultrasonication and aqueous enzymatic oil extraction (using an alkaline protease at pH = 9.0) method to extract oil from J. curcas seeds and obtained 74% of the seed oil which is very large compared to the 17–20% oil extracted by aqueous oil extraction alone. Moreover, using of ultrasonication also resulted in reducing the process time from 18 to 6 h. The main advantages of using enzymatic oil extraction are that it is environmental-friendly and does not produce volatile organic compounds. However, the long process time is the main disadvantage associated with this technique [91].

    Table 7 shows the reaction temperature, reaction pH, time consumption and oil yield of different chemical and enzymatic extraction methods tested on J. curcas. It has been found that the chemical extraction using n-hexane method results in the highest oil yield which makes it the most commonly used method. Moreover, the negative environmental impacts associated with solvent extraction can be reduced significantly by using AEOE technique although the later method takes long time to complete the process [83,91].

    Table 7. Reported oil yields percentage for different chemical and enzymatic extraction methods and different reaction parameters for J. curcas.
    Extraction technique Reaction temperature (℃) Reaction pH Time consumption (h) Oil yield (%) Reference
    n-Hexane oil extraction (Soxhlet) apparatus - - 24 95–99 [86]
    First acetone, second n-hexane - - 48 - [98]
    AOE 50 9 6 38 [83,97]
    AOE with 10 min of ultrasonication as pre-treatment 50 9 6 67 [83,97]
    AEOE (hemicellulase or cellulase) 60 4.5 2 73 [6,13,83]
    AEOE (alkaline protease) 60 7 2 86 [6,13,83]
    50 9 6 64 [83]
    AEOE (alkaline protease) with 5 min of ultrasonication as pre-treatment 50 9 6 74 [83,97]
    Three-phase partitioning 25 9 2 97 [83,99]
     | Show Table
    DownLoad: CSV

    3.2.5. Supercritical fluid extraction (SFE)

    Supercritical fluid extraction (SFE) technique is used to avoid the use of organic solvents and to increase the speed of extraction [4]. SFE using CO2 has numerous advantages over the solvent extraction [92,100]. It uses CO2as a solvent which is a nontoxic, inexpensive, nonflammable, and nonpolluting supercritical fluid solvent for the extraction of natural products, and also almost 100% oil can be extracted by this method [100].

    Maran and Priya [101] have used a supercritical fluid extraction (at 44 MPa, 49.8 ℃, and 0.64 g/min of CO2 flow rate and within 81 min) method for extraction of oil from muskmelon seed (Cucumis melo) and produced slightly higher oil yield (48.11 ± 0.04%) than that of Soxhlet extraction method (46.83 ± 0.29%). Moreover, these authors reported that the fatty acids composition of muskmelon seed oil extracted by SFE was similar to that of Soxhlet extraction. However, the main limitation of the SFE is the high cost at production scale, not only due to the use of high pressure equipment but also because of the raw material should be freeze dried to reduce its moisture to values below 20%, as high water concentration in fluid phase negatively affects the oil yield [102,103].


    3.2.6. Microwave-assisted extraction (MAE)

    Microwave-assisted extraction (MAE) also called microwave extraction, is a new extraction technique, which combines microwave and traditional solvent extraction [104]. MAE has been recognized as a technique with several advantages over other extraction processes, such as reduction of costs, shorter time, less solvent, higher extraction rate, better products with lower cost, reduce energy consumption and CO2emissions [104,105]. In microwave-assisted aqueous enzymatic extraction (MAAEE) of pumpkin seed oil by using mixtures of cellulose, pectinase and proteinase (w/w/w), Jiao et al. [106] obtained the highest oil recovery of 64.17%. The authors also reported that there were no significant variations in physicochemical properties of MAAEE and soxhlet extracted oils, and thus, MAAEE is a promising and environmental-friendly technique for pumpkin seed oil extraction. Moreover, it has been found that the MAE method needs a few minutes compared to SFE and the apparatus of MAE extraction is simpler and cheaper, and can be used with a variety of materials with less limit of the polarity of extractants [104]. Therefore, MAE extraction is an interesting alternative to conventional liquid solvent extraction methods, especially in the case of plant material [4,104]. In microwave-assisted solvent extraction of oil from soybeans and rice bran by using solvent (ethanol) to feedstock ratio of 3:1, the maximum oil yields of 17.3% and 17.2% at 20 min and 120 ℃ were achieved as compared to 11.3% and 12.4% using control extraction for soybeans and rice bran, respectively [107].


    4. Advantages and Disadvantages of Main Oil Extraction Methods

    From the above discussions, it is possible to observe that each method of oil extraction has its own advantages and disadvantages. The advantages and disadvantages of the main three oil extraction methods: mechanical, chemical or solvent and ASE are summarized in Table 8.

    Table 8. Advantages and disadvantages of main three oil extraction methods [4,82,108].
    Methods Advantages Disadvantages
    Oil press √ Virgin oil is more sought after · Generally ineffective in beauty leaf oil extraction
    √ No potential for solvent contamination · Time and labor intensive
    √ Relatively inexpensive after initial capital costs · Relatively low oil yields
    √ Minor consumable costs · Operators require experience to achieve best results
    √ Whole seeds or kernels can be processed · High dependence on kernel moisture content
    √ No environmental problem regarding the use of screw press · Relatively dirty process
    · Filtration or degumming process pf oil is required
    · Low and inconsistent oil production
    · High oil loss
    n-Hexane √ Repeatable and reproducible results and process · Less sought after than virgin oil
    √ High oil yields · High potential for solvent contamination
    √ Relatively simple and quick · Safety issues and environmental concerns
    √ Suitable for bulk oil extraction · Very costly if the hexane cannot be recovered
    √ Low capital investment · High hexane requirement
    √ No especial equipment required ü Hexane can be recovered and reused, reducing cost significantly · Only kernel can be processed
    ASE √ Automatic technique · Very high initial cost
    √ Condition can be optimized · High preparation required
    √ More efficient · Special equipment and skill required
    √ Clean process · Potential for solvent contamination
    √ Relatively less solvent consumption ü Less time and labor incentives ü High oil yield · Only kernel can be processed
     | Show Table
    DownLoad: CSV

    5. Single and Combined Oil Extraction Methods to Reduces Problems of Extraction

    Traditional oil extraction methods have their own advantages and disadvantages. To overcome the disadvantages and improve the strong sides, different oil extraction methods are combined. Moreover, to decrease the environmental impacts of solvents of chemical extraction, different methods of oil extraction have been developed. For instance, Conte, et al. [109] have extracted safflower oil by Soxhlet extraction, ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) techniques (using pressurized ethanol). Soxhlet and ultrasound-assisted extractions gave maximum global oil yield of 36.53% and 30.41%, respectively (70 ℃ and 240 min) while a maximum global yield for pressurized liquid extraction would be 25.62% [109]. According to the authors, although traditional extraction methods (Soxhlet and UAE) showed maximum global oil yields, the advantages derived from PLE make it a promising alternative for the extraction of essential oil from vegetable matrices due to the reduction of solvent consumption and extraction time.

    At optimal conditions of sonication, ultrasonic-assisted extraction (UAE) of raspberry seed oil was able to provide a higher content of beneficial unsaturated fatty acids, whereas conventional Soxhlet extraction resulted in a higher amount of saturated fatty acids [110]. Ultrasound-assisted extraction gave grape seed oil yield (14% w/w) similar to Soxhlet extraction in 6 hours, and no significant differences for the major fatty acids was observed in oils extracted by both methods. The advantage of using ultrasound is that it's lower solvent consumption and a shorter extraction time [111].


    6. Future Prospective of Oil Extraction Methods

    Biodiesel production from non-edible feedstocks is increasingly attractive alternative to both fossil diesels and renewable fuels derived from food crops. Thus, one of the current research focus in biodiesel production is optimization of oil extraction methods from non-edible oils sources, characterization the oils and suitability test for biodiesel [112], and searching for appropriate methods of biodiesel production from these oils [4,17]. Non-edible biodiesel feedstocks include non-edible oils, animal fats and waste oils [4,13] and algal biomass [10,11,12]. Some of the recently optimized non-edible seed oil extraction methods include extraction from seeds of waste date pits (Phoenix dactylifera L.) [112], Sesame (Sesamum indicumL.) [113], jatropha seed kernels [114], beauty leaf seed(Calophyllum inophyllum) [85], Moringa oleifera [115] and karanja (Pongamia pinnata) [116].

    According to Sajjadi et al. [17], animal fats are important feedstocks for biodiesel production as their cost is substantially lower than the cost of vegetable oil. However, many types of animal fats contain high amount of saturated fatty acids, which make the transesterification process difficult. To overcome such problems, various biodiesel production methods have been optimized by different investigators. For instance, Kumar and Math [117] investigated the combined effects of catalyst (NaOH) concentration, reaction time and methanol quantity on biodiesel yield from waste animal fat at 55 ℃ to 60 ℃, and obtained the maximum animal fat methyl ester yield of 91% v/v, at 35% v/v methanol and 0.46% w/v catalyst within 90 minutes. Chakraborty and Sahu [118] have also carried out a study on the impacts of methanol to goat tallow molar ratio, infrared radiation assisted reactor (IRAR) temperature and H2SO4 concentration on the tallow conversion to biodiesel. Under optimal conditions, 96.7% FFA conversion was achieved within 2.5 h at 59.93 wt.% H2SO4, 69.97 ℃ IRAR temperature and 31.88:1 methanol to tallow molar ratio. According to the authors, infrared radiation strategy could significantly reduce the reaction time compared to conventionally heated reactor while providing appreciably high biodiesel yield. Nuhu and Kovo [119] used a two-step transesterification to produce biodiesel from chicken fat due to the presence of high FFA (4.16%) in the feedstock, and the first esterification step was a pretreatment process that could reduce the FFA to 0.43%. The second step, the transesterification reaction, yielded 93.4% fat methyl ester from 50g of chicken fat at 60 ℃ reaction temperature and within 2 hours corresponding to 6:1 molar ratio of oil-to-methanol and 1% wt catalyst concentration.

    From various types of biomass, microalgae have the potential of becoming a significant energy source for biofuel production in the coming years. Currently, researches are mainly focusing on optimization of cultivation methods and the conversion of microalgae to biodiesel (lipids for biodiesel production) [120]. Martinez-Guerra and Gude [121] has also wrote that algal biodiesel production will play a significant role in sustaining future transportation fuel supplies, and a large number of researchers around the world are investigating into making this process sustainable by increasing the energy gains and by optimizing resource-utilization efficiencies. Some of the studies that focus on optimization of biodiesel production from microalgae include the investigations by Misau et al. [122], Gülyurt et al. [123], Barreiro, et al. [120] and Rajendran et al. [124].


    7. Conclusions

    The increasing demand of energy, where the major part of that energy is derived from fossil sources and the problem associated with petroleum fuels have led to search for renewable alternative energy sources of which biodiesel is a promising alternative. The potential feedstock of biodiesel include, edible and non-edible oils, animal fats, waste oils and algal biomass. However, nowadays, more than 95% of the world biodiesel is produced from edible oils and this resulted in food versus fuel debates, rising in the price of oil and environmental problems. To overcome these problems, it is important to use relatively cheaper and non-edible biodiesel feedstock such as non-edible oils, waste animal fats and waste oils.

    Many non-edible plat oils have fatty acid composition and other physico-chemical properties that enable them to be suitable for biodiesel production as that of edible oils. Moreover, many potential non-edible plant oil for biodiesel have been identified, and the oil extraction and biodiesel production methods have also been optimized. Methods to extract oil from waste animal fats and refining animal oils and waste oils, and converting them to biodiesel were also optimized by different scholars.

    The major oil extraction methods are mechanical extraction, chemical or solvent extraction, and enzymatic extraction. From these methods, chemical or solvent oil extraction method, particularly, Soxhlet extraction by using hexane as solvent, is the most widely used method due to its efficiency of oil extraction. However, chemical oil extraction method has a negative environmental impact. There are also other oil extraction method such as accelerated solvent extraction, supercritical fluid extraction, microwave-assisted extraction and ultrasonic-assisted extraction.

    All oil extraction methods have their own advantages and disadvantages. Therefore, by combining the appropriate oil extraction methods, it is possible to reduce the disadvantages and improve the oil extraction efficiency and reduce the negative environmental impacts. Furthermore, for non-edible and low-cost biodiesel feedstocks gradually gain acceptance and well establish and continue to settle in the biodiesel market, various aspects must be scrutinized and studied. Researches that focus on the study of low-cost biodiesel feedstocks, various efficient and environmental-friendly oil extraction techniques, and study of oil yield and fatty acid profiles of non-edible oils, animal fats and waste oils and efficient and cost effective biodiesel conversion technologies are crucial. It can also be concluded that the emphasis must be given to those feedstocks which are neither compete with food crops nor lead to land clearing, and provide significant greenhouse-gas reductions.


    Acknowledgments

    The authors would like to express their gratitude to the EnPe/NORHED project of Norad at the Norwegian University of Life Sciences, Faculty of Sciences and Technology for their financial support.


    Conflict of Interest

    All authors declare no conflicts of interest in this paper.




    [1] S. B. Gaikwad, M. S. Joshi, Brain tumor classification using principal component analysis and probabilistic neural network, Int. J. Comput. Appl., 120 (2015), 5-9.
    [2] Q. T. Ostrom, G. Cioffi, H. Gittleman, N. Patil, K. Waite, C. Kruchko, et al., CBTRUS statistical report: primary brain and other central nervous system tumors diagnosed in the United States in 2012-2016, Neuro. Oncol., 21 (2019), v1-v100. doi: 10.1093/neuonc/noz150
    [3] D. N. Louis, A. Perry, G. Reifenberger, A. von Deimling, D. Figarella-Branger, W. K. Cavenee, et al., The 2016 World Health Organization Classification of tumors of the central nervous system: A summary, Acta Neuropathol., 131 (2016), 803-820. doi: 10.1007/s00401-016-1545-1
    [4] Z. N. K. Swati, Q. Zhao, M. Kabir, F. Ali, Z. Ali, S. Ahmed, et al., Content-Based brain tumor retrieval for MR images using transfer learning, IEEE Access, 7 (2019), 17809-17822. doi: 10.1109/ACCESS.2019.2892455
    [5] S. Pereira, R. Meier, V. Alves, M. Reyes, C. A. Silva, Automatic brain tumor grading from mri data using convolutional neural networks and quality assessment, in: Understanding and interpreting machine learning in medical image computing applications, Springer, Cham., 2018,106-114.
    [6] S. Deepak, P. M. Ameer, Brain tumor classification using deep CNN features via transfer learning, Comput. Biol. Med., 111 (2019), 103345. doi: 10.1016/j.compbiomed.2019.103345
    [7] K. Machhale, H. B. Nandpuru, V. Kapur, L. Kosta, MRI brain cancer classification using hybrid classifier (SVM-KNN), in: 2015 Int. Conf. Ind. Instrum. Control, IEEE, 2015, 60-65.
    [8] S. Rathore, M. Hussain, M. Aksam Iftikhar, A. Jalil, Ensemble classification of colon biopsy images based on information rich hybrid features, Comput. Biol. Med., 47 (2014), 76-92. doi: 10.1016/j.compbiomed.2013.12.010
    [9] S. Rathore, M. Hussain, A. Khan, Automated colon cancer detection using hybrid of novel geometric features and some traditional features, Comput. Biol. Med., 65 (2015) 279-296. doi: 10.1016/j.compbiomed.2015.03.004
    [10] L. Hussain, A. Ahmed, S. Saeed, S. Rathore, I. A. Awan, S. A. Shah, et al., Prostate cancer detection using machine learning techniques by employing combination of features extracting strategies, Cancer Biomarkers, 21 (2018), 393-413. doi: 10.3233/CBM-170643
    [11] Y. Asim, B. Raza, A. Kamran, M. Saima, A.K. Malik, S. Rathore, et al., A multi-modal, multi-atlas-based approach for Alzheimer detection via machine learning, Int. J. Imag. Sys. Tech., 28 (2018), 113-123. doi: 10.1002/ima.22263
    [12] A. Islam, M. F. Hossain, C. Saha, A new hybrid approach for brain tumor classification using BWT-KSVM, in: 2017 4th Int. Conf. Adv. Electr. Eng., IEEE, 2017,241-246.
    [13] P. P. Rebouças Filho, E. de S. Rebouças, L. B. Marinho, R. M. Sarmento, J. M. R. S. Tavares, V. H. C. de Albuquerque, Analysis of human tissue densities: A new approach to extract features from medical images, Pattern Recognit. Lett., 94 (2017), 211-218. doi: 10.1016/j.patrec.2017.02.005
    [14] B. Dhruv, N. Mittal, M. Modi, Study of Haralick's and GLCM texture analysis on 3D medical images, Int. J. Neurosci., 129 (2019), 350-362. doi: 10.1080/00207454.2018.1536052
    [15] Q. Zheng, H. Li, B. Fan, S. Wu, J. Xu, Integrating support vector machine and graph cuts for medical image segmentation, J. Vis. Commun. Image Represent, 55 (2018), 157-165. doi: 10.1016/j.jvcir.2018.06.005
    [16] S. A. Taie, W. Ghonaim, Title CSO-based algorithm with support vector machine for brain tumor's disease diagnosis, in: 2017 IEEE Int. Conf. Pervasive Comput. Commun. Work. (PerCom Work.), IEEE, 2017,183-187.
    [17] M. K. Abd-Ellah, A. I. Awad, A. A. M. Khalaf, H. F. A. Hamed, Classification of brain tumor MRIs using a kernel support vector machine, in: International Conference on Well-Being in the Information Society, Springer, Cham. 2016,151-160.
    [18] H. Alquran, I. A. Qasmieh, A. M. Alqudah, S. Alhammouri, E. Alawneh, A. Abughazaleh, et al., The melanoma skin cancer detection and classification using support vector machine, in: 2017 IEEE Jordan Conf. Appl. Electr. Eng. Comput. Technol., IEEE, 2017, 1-5.
    [19] S. Wang, S. Du, A. Atangana, A. Liu, Z. Lu, Application of stationary wavelet entropy in pathological brain detection, Multimed. Tools Appl., 77 (2018), 3701-3714. doi: 10.1007/s11042-017-4476-5
    [20] Y. Zhang, J. Yang, S. Wang, Z. Dong, P. Phillips, Pathological brain detection in MRI scanning via Hu moment invariants and machine learning, J. Exp. Theor. Artif. Intell., 29 (2017), 299-312. doi: 10.1080/0952813X.2015.1132274
    [21] J. Cheng, W. Yang, M. Huang, W. Huang, J. Jiang, Y. Zhou, et al., Retrieval of brain tumors by adaptive spatial pooling and fisher vector representation, PLoS One, 11 (2016), e0157112. doi: 10.1371/journal.pone.0157112
    [22] J. Cheng, W. Huang, S. Cao, R. Yang, W. Yang, Z. Yun, et al., Enhanced performance of brain tumor classification via tumor region augmentation and partition, PLoS One., 10 (2015), e0140381. doi: 10.1371/journal.pone.0140381
    [23] N. Abiwinanda, M. Hanif, S. T. Hesaputra, A. Handayani, T. R. Mengko, Brain tumor classification using convolutional neural network, in: World Congr. Med. Phys. Biomed. Eng. 2018, Springer, Singapore, 2019,183-189.
    [24] M. Sajjad, S. Khan, K. Muhammad, W. Wu, A. Ullah, S. W. Baik, Multi-grade brain tumor classification using deep CNN with extensive data augmentation, J. Comput. Sci., 30 (2019), 174-182. doi: 10.1016/j.jocs.2018.12.003
    [25] R. Zia, P. Akhtar, A. Aziz, A new rectangular window based image cropping method for generalization of brain neoplasm classification systems, Int. J. Imag. Syst. Technol., 28 (2018), 153-162. doi: 10.1002/ima.22266
    [26] M. M. Badža, M. Č. Barjaktarović, Classification of brain tumors from MRI images using a convolutional neural network, Appl. Sci., 10 (2020), 1999. doi: 10.3390/app10061999
    [27] A. Gumaei, M. M. Hassan, M. R. Hassan, A. Alelaiwi, G. Fortino, A hybrid feature extraction method with regularized extreme learning machine for brain tumor classification, IEEE Access, 7 (2019), 36266-36273. doi: 10.1109/ACCESS.2019.2904145
    [28] Z. Huang, X. Du, L. Chen, Y. Li, M. Liu, Y. Chou, et al., Convolutional neural network based on complex networks for brain tumor image classification with a modified activation function, IEEE Access, 8 (2020), 89281-89290. doi: 10.1109/ACCESS.2020.2993618
    [29] L. Hussain, I. A. Awan, W. Aziz, S. Saeed, A. Ali, F. Zeeshan, et al., Detecting congestive heart failure by extracting multimodal features and employing machine learning techniques, Biomed. Res. Int., 2020 (2020), 1-19.
    [30] L. Hussain, W. Aziz, S. Saeed, I. A. Awan, A. A. Abbasi, N. Maroof, Arrhythmia detection by extracting hybrid features based on refined Fuzzy entropy (FuzEn) approach and employing machine learning techniques, Waves Rand. Complex Media., 30 (2020), 656-686. doi: 10.1080/17455030.2018.1554926
    [31] D. S. Guru, Y. H. Sharath, S. Manjunath, Texture features and KNN in classification of flower images, Int. J. Comput. Appl., (2010), 21-29.
    [32] A. N. Esgiar, R. N. Naguib, B. S. Sharif, M. K. Bennett, A. Murray, Microscopic image analysis for quantitative measurement and feature identification of normal and cancerous colonic mucosa, IEEE Trans. Inf. Technol. Biomed., 2 (1998), 197-203. doi: 10.1109/4233.735785
    [33] A. N. Esgiar, R. N. G. Naguib, B. S. Sharif, M. K. Bennett, A. Murray, Fractal analysis in the detection of colonic cancer images, IEEE Trans. Inf. Technol. Biomed., 6 (2002), 54-58. doi: 10.1109/4233.992163
    [34] M. Masseroli, A. Bollea, G. Forloni, Quantitative morphology and shape classification of neurons by computerized image analysis, Comput. Methods Programs Biomed., (1993), 89-99.
    [35] Y. M. Li, X. P. Zeng, A new strategy for urinary sediment segmentation based on wavelet, morphology and combination method, Comput. Methods Programs Biomed., 84 (2006), 162-173. doi: 10.1016/j.cmpb.2006.07.010
    [36] A. Hyvä;rinen, E. Oja, Independent component analysis: Algorithms and applications, Neural Networks, 13 (2000), 411-430. doi: 10.1016/S0893-6080(00)00026-5
    [37] Y. Xiao, Z. Zhu, Y. Zhao, Kernel reconstruction ICA for sparse representation, IEEE Trans. Neural Networks Learn. Syst., 26 (2015), 1222-1232. doi: 10.1109/TNNLS.2014.2334711
    [38] J. Hurri, P. O. Hoyer, Natural Image Statistics, A probabilistic approach to early computational vision, Springer Science & Business Media, 39 (2009).
    [39] Q. V. Le, A. Karpenko, J. Ngiam, A. Y. Ng, ICA with reconstruction cost for efficient overcomplete feature learning, Adv. Neural. Inform. Process Syst., 24 (2011), 1017-1025.
    [40] Q. V. Le, M. A. Ranzato, M. Devin, G. S. Corrado, A. Y. Ng, Building high-level features using large scale unsupervised learning, In 2013 IEEE international conference on acoustics, speech and signal processing, IEEE, (2013), 8595-8598
    [41] Y. Boureau, A theoretical analysis of feature pooling in visual recognition, In Proceedings of the 27th international conference on machine learning (ICML-10), (2010), 111-118.
    [42] Y. Lecun, Learning invariant feature hierarchies, In European conference on computer vision, Springer, Berlin, Heidelberg, (2012), 496-505
    [43] A. P. Dobrowolski, M. Wierzbowski, K. Tomczykiewicz, Multiresolution MUAPs decomposition and SVM-based analysis in the classification of neuromuscular disorders, Comput. Methods Programs Biomed., 107 (2012), 393-403. doi: 10.1016/j.cmpb.2010.12.006
    [44] J. Schmidhuber, Deep learning in neural networks: An overview, Neural Networks, 61 (2015), 85-117. doi: 10.1016/j.neunet.2014.09.003
    [45] H. Papadopoulos, V. Vovk, A. Gammerman, Guest editors' preface to the special issue on conformal prediction and its applications, Ann. Math. Artif. Intell., 74 (2015), 1-7. doi: 10.1007/s10472-014-9429-3
    [46] N. Kambhatla, T. K. Leen, Dimension reduction by local principal component analysis, Neural Comput., 9 (1997), 1493-1516. doi: 10.1162/neco.1997.9.7.1493
    [47] A. Pathak, B. Vohra, K. Gupta, Supervised learning approach towards class separability-linear discriminant analysis, in: 2019 Int. Conf. Intell. Comput. Control Syst., IEEE, (2019), 1088-1093.
    [48] W. Yang, Q. Feng, M. Yu, Z. Lu, Y. Gao, Y. Xu, et al., Content-based retrieval of brain tumor in contrast-enhanced MRI images using tumor margin information and learned distance metric, Med. Phys., 39 (2012), 6929-6942. doi: 10.1118/1.4754305
    [49] M. Huang, W. Yang, M. Yu, Z. Lu, Q. Feng, W. Chen, Retrieval of brain tumors with region-specific bag-of-visual-words representations in contrast-enhanced MRI images, Comput. Math. Methods Med., 2012 (2012), 1-17.
    [50] M. Huang, W. Yang, Y. Wu, J. Jiang, Y. Gao, Y. Chen, et al., Content-based image retrieval using spatial layout information in brain tumor T1-weighted contrast-enhanced mr images, PLoS One, 9 (2014), e102754. doi: 10.1371/journal.pone.0102754
    [51] P. Afshar, K. N. Plataniotis, A. Mohammadi, Capsule networks for brain tumor classification based on mri images and coarse tumor boundaries, in: ICASSP 2019 - 2019 IEEE Int. Conf. Acoust. Speech Signal Process., IEEE, (2019), 1368-1372.
    [52] P. Afshar, A. Mohammadi, K. N. Plataniotis, Brain tumor type classification via capsule networks, in: 2018 25th IEEE Int. Conf. Image Process., IEEE, (2018), 3129-3133.
    [53] J. S. Paul, A. J. Plassard, B. A. Landman, D. Fabbri, Deep learning for brain tumor classification, in: Medical Imaging 2017: Biomedical Applications in Molecular, Structural, and Functional Imaging., International Society for Optics and Photonics, 10137 (2017), 1013710.
    [54] E. I. Zacharaki, S. Wang, S. Chawla, D. Soo, R. Yoo, E. R. Wolf, et al., Classification of brain tumor type and grade using MRI texture and shape in a machine learning scheme, Magn. Reson. Med., 62 (2009), 1609-1618. doi: 10.1002/mrm.22147
    [55] A. Kabir Anaraki, M. Ayati, F. Kazemi, Magnetic resonance imaging-based brain tumor grades classification and grading via convolutional neural networks and genetic algorithms, Biocybern. Biomed. Eng., 39 (2019), 63-74. doi: 10.1016/j.bbe.2018.10.004
    [56] J. Sachdeva, V. Kumar, I. Gupta, N. Khandelwal, C. K. Ahuja, Segmentation, feature extraction, and multiclass brain tumor classification, J. Digit. Imag., 26 (2013), 1141-1150. doi: 10.1007/s10278-013-9600-0
    [57] R. A. Lerski, K. Straughan, L. R. Schad, D. Boyce, S. Blüml, I. Zuna, VⅢ. MR image texture analysis-An approach to tissue characterization, Magn. Reson. Imaging., 11 (1993), 873-887. doi: 10.1016/0730-725X(93)90205-R
    [58] S. Herlidou-Même, J. Constans, B. Carsin, D. Olivie, P. Eliat, L. Nadal-Desbarats, et al., MRI texture analysis on texture test objects, normal brain and intracranial tumors, Magn. Reson. Imaging., 21 (2003), 989-993. doi: 10.1016/S0730-725X(03)00212-1
    [59] L. R. Schad, S. Blüml, I. Zuna, IX. MR tissue characterization of intracranial tumors by means of texture analysis, Magn. Reson. Imaging., 11 (1993), 889-896. doi: 10.1016/0730-725X(93)90206-S
    [60] A. Devos, A.W. Simonetti, M. van der Graaf, L. Lukas, J. A. K. Suykens, L. Vanhamme, et al., The use of multivariate MR imaging intensities versus metabolic data from MR spectroscopic imaging for brain tumour classification, J. Magn. Reson., 173 (2005), 218-228. doi: 10.1016/j.jmr.2004.12.007
    [61] L. Lukas, A. Devos, J. A. K. Suykens, L. Vanhamme, F. A. Howe, C. Majós, et al., Brain tumor classification based on long echo proton MRS signals, Artif. Intell. Med., 31 (2004), 73-89. doi: 10.1016/j.artmed.2004.01.001
    [62] A. Devos, L. Lukas, J. A. K. Suykens, L. Vanhamme, A. R. Tate, F. A. Howe, et al., Classification of brain tumours using short echo time 1H MR spectra, J. Magn. Reson., 170 (2004), 164-175. doi: 10.1016/j.jmr.2004.06.010
    [63] Y. Huang, P. J. G. Lisboa, W. El-Deredy, Tumour grading from magnetic resonance spectroscopy: A comparison of feature extraction with variable selection, Stat. Med., 22 (2003), 147-164. doi: 10.1002/sim.1321
    [64] A. R. Tate, C. Majós, A. Moreno, F. A. Howe, J. R. Griffiths, C. Arús, Automated classification of short echo time in in vivo 1 H brain tumor spectra: A multicenter study, Magn. Reson. Med., 49 (2003), 29-36. doi: 10.1002/mrm.10315
    [65] Y. D. Cho, G. H. Choi, S. P. Lee, J. K. Kim, 1H-MRS metabolic patterns for distinguishing between meningiomas and other brain tumors, Magn. Reson. Imaging., 21 (2003), 663-672. doi: 10.1016/S0730-725X(03)00097-3
    [66] Y. Pan, W. Huang, Z. Lin, W. Zhu, J. Zhou, J. Wong, et al., Brain tumor grading based on Neural Networks and Convolutional Neural Networks, in: 2015 37th Annu. Int. Conf. IEEE Eng. Med. Biol. Soc., IEEE, (2015), 699-702.
  • This article has been cited by:

    1. Kiky Corneliasari SEMBIRING, Shiro SAKA, Renewable Hydrocarbon Fuels from Plant Oils for Diesel and Gasoline, 2019, 62, 1346-8804, 157, 10.1627/jpi.62.157
    2. Gebresilassie Asnake Ewunie, John Morken, Odd Ivar Lekang, Zerihun Demrew Yigezu, Factors affecting the potential of Jatropha curcas for sustainable biodiesel production: A critical review, 2021, 137, 13640321, 110500, 10.1016/j.rser.2020.110500
    3. Emilia Paone, Antonio Tursi, 2021, 9780128216019, 165, 10.1016/B978-0-12-821601-9.00006-6
    4. Chiena L. Palconite, Alexandra C. Edrolin, Sheryl Nope B. Lustre, Aldin A. Manto, John Rey L. Caballero, Maribel S. Tizo, Alexander L. Ido, Renato O. Arazo, Optimization and characterization of bio-oil produced from Ricinus communis seeds via ultrasonic-assisted solvent extraction through response surface methodology, 2018, 28, 24682039, 444, 10.1016/j.serj.2018.07.006
    5. Abdul Haq, Sana Adeel, Alam Khan, Qurrat ul ain Rana, Muhammad Adil Nawaz Khan, Muhammad Rafiq, Muhammad Ishfaq, Samiullah Khan, Aamer Ali Shah, Fariha Hasan, Safia Ahmed, Malik Badshah, Screening of Lipase-Producing Bacteria and Optimization of Lipase-Mediated Biodiesel Production from Jatropha curcas Seed Oil Using Whole Cell Approach, 2020, 13, 1939-1234, 1280, 10.1007/s12155-020-10156-1
    6. Homa Hosseinzadeh-Bandbafha, Meisam Tabatabaei, Mortaza Aghbashlo, Anh Tuan Hoang, Yi Yang, Gholamreza Salehi Jouzani, 2020, Chapter 9, 978-3-030-44487-7, 199, 10.1007/978-3-030-44488-4_9
    7. Adeyinka Sikiru Yusuff, Parametric optimization of solvent extraction of Jatropha curcas seed oil using design of experiment and its quality characterization, 2021, 35, 10269185, 60, 10.1016/j.sajce.2020.11.006
    8. J. M. Shabani, O. O. Babajide, O. O. Oyekola, 2020, Chapter 14, 978-3-030-38031-1, 285, 10.1007/978-3-030-38032-8_14
    9. Artur Olszak, Karol Osowski, Ireneusz Musiałek, Elżbieta Rogoś, Andrzej Kęsy, Zbigniew Kęsy, Application of Plant Oils as Ecologically Friendly Hydraulic Fluids, 2020, 10, 2076-3417, 9086, 10.3390/app10249086
    10. S. K. Ram, L. R. Kumar, S. K. Yellapu, R. Kaur, R. D. Tyagi, 2019, 9780784415344, 527, 10.1061/9780784415344.ch22
    11. Sophie Parsons, Sofia Raikova, Christopher J. Chuck, The viability and desirability of replacing palm oil, 2020, 3, 2398-9629, 412, 10.1038/s41893-020-0487-8
    12. Achmad Syafiuddin, Jia Hao Chong, Adhi Yuniarto, Tony Hadibarata, The current scenario and challenges of biodiesel production in Asian countries: A review, 2020, 12, 2589014X, 100608, 10.1016/j.biteb.2020.100608
    13. Hossein Esmaeili, Ehsan Nourafkan, Mehdi Nakisa, Waqar Ahmed, 2021, 9780128213469, 149, 10.1016/B978-0-12-821346-9.00005-5
    14. A. Santhoshkumar, Vinoth Thangarasu, R. Anand, 2019, 9780081027912, 291, 10.1016/B978-0-08-102791-2.00012-X
    15. Saxon Paiz, José Martim Costa Junior, Péricles Crisiron Pontes, Juliana Damasceno da C. G. de Carvalho, Diego Busson de Moraes, Cristiane Gimenes de Souza, Carolina Palma Naveira-Cotta, Experimental parametric analysis of biodiesel synthesis in microreactors using waste cooking oil (WCO) in ethilic route, 2022, 44, 1678-5878, 10.1007/s40430-022-03476-0
    16. Rahul Chamola, Nitin Kumar, Siddharth Jain, 2022, Chapter 32, 978-981-16-8340-4, 395, 10.1007/978-981-16-8341-1_32
    17. Misael B. Sales, Pedro T. Borges, Manoel Nazareno Ribeiro Filho, Lizandra Régia Miranda da Silva, Alyne P. Castro, Ada Amelia Sanders Lopes, Rita Karolinny Chaves de Lima, Maria Alexsandra de Sousa Rios, José C. S. dos Santos, Sustainable Feedstocks and Challenges in Biodiesel Production: An Advanced Bibliometric Analysis, 2022, 9, 2306-5354, 539, 10.3390/bioengineering9100539
    18. Youhua Zhang, Linhai Duan, Hossein Esmaeili, A review on biodiesel production using various heterogeneous nanocatalysts: Operation mechanisms and performances, 2022, 158, 09619534, 106356, 10.1016/j.biombioe.2022.106356
    19. Kedir D. Mekonnen, Zenamarkos B. Sendekie, NaOH-Catalyzed Methanolysis Optimization of Biodiesel Synthesis from Desert Date Seed Kernel Oil, 2021, 6, 2470-1343, 24082, 10.1021/acsomega.1c03546
    20. Fatima Akram, Ikram ul Haq, Saleha Ibadat Raja, Azka Shahzad Mir, Sumbal Sajid Qureshi, Amna Aqeel, Fatima Iftikhar Shah, Current trends in biodiesel production technologies and future progressions: A possible displacement of the petro-diesel, 2022, 370, 09596526, 133479, 10.1016/j.jclepro.2022.133479
    21. Adepoju T. F, H.A. Akens, E.B. Ekeinde, Synthesis of biodiesel from blend of seeds oil-animal fat employing agricultural wastes as base catalyst, 2022, 5, 26660164, 100202, 10.1016/j.cscee.2022.100202
    22. Juvet Malonda Shabani, Alechine E. Ameh, Oluwaseun Oyekola, Omotola O. Babajide, Leslie Petrik, Fusion-Assisted Hydrothermal Synthesis and Post-Synthesis Modification of Mesoporous Hydroxy Sodalite Zeolite Prepared from Waste Coal Fly Ash for Biodiesel Production, 2022, 12, 2073-4344, 1652, 10.3390/catal12121652
    23. Natei Ermias Benti, Abreham Berta Aneseyee, Chernet Amente Geffe, Tegenu Argaw Woldegiyorgis, Gamachis Sakata Gurmesa, Mesfin Bibiso, Ashenafi Abebe Asfaw, Abnet Woldesenbet Milki, Yedilfana Setarge Mekonnen, Biodiesel production in Ethiopia: Current status and future prospects, 2023, 19, 24682276, e01531, 10.1016/j.sciaf.2022.e01531
    24. Michael Traver, Alexandra Ebbinghaus, Kjell Moljord, Kai Morganti, Richard Pearson, Monique Vermeire, 2022, 1412, 9780841297968, 83, 10.1021/bk-2022-1412.ch003
    25. Shangeetha Ganesan, Hao Sen Siow, Akintomiwa O. Esan, Sivajothi Nadarajah, Nur Liyana Abdul Manaff, 2022, 9780128242957, 1, 10.1016/B978-0-12-824295-7.00003-6
    26. Muhamad Fikry Nasrudin, Zainal Alim Mas’ud, Mohammad Khotib, Quality of Tobacco Seed Oil from Voor-Oogst Variety Using Ultrasonic-Assisted Extraction, 2022, 1061, 1662-9752, 129, 10.4028/p-l6t2jt
    27. Yu‐Shen Cheng, Kittipong Rattanaporn, Malinee Sriariyanun, 2022, 9783527348763, 287, 10.1002/9783527830756.ch15
    28. Hossein Esmaeili, A critical review on the economic aspects and life cycle assessment of biodiesel production using heterogeneous nanocatalysts, 2022, 230, 03783820, 107224, 10.1016/j.fuproc.2022.107224
    29. Babu Dharmalingam, S. Balamurugan, Unalome Wetwatana, Vut Tongnan, Chandra Sekhar, Baranitharan Paramasivam, Kraipat Cheenkachorn, Atthasit Tawai, Malinee Sriariyanun, Comparison of neural network and response surface methodology techniques on optimization of biodiesel production from mixed waste cooking oil using heterogeneous biocatalyst, 2023, 340, 00162361, 127503, 10.1016/j.fuel.2023.127503
    30. Vlada B. Veljković, Milan D. Kostić, Olivera S. Stamenković, Camelina seed harvesting, storing, pretreating, and processing to recover oil: A review, 2022, 178, 09266690, 114539, 10.1016/j.indcrop.2022.114539
    31. Mohammed Takase, Subhan Danish, A Critical Review of Croton as a Multipurpose Nonedible Tree Plant for Biodiesel Production towards Feedstock Diversification for Sustainable Energy, 2022, 2022, 2314-7539, 1, 10.1155/2022/5895160
    32. Gang Wei, Zidong Zhang, Dongmei Fu, Yuanyuan Zhang, Weipeng Zhang, Yuangang Zu, Lin Zhang, Zhi Zhang, Enzyme-assisted Solvent Extraction of High-yield Paeonia suffruticosa Andr. Seed Oil and Fatty Acid Composition and Anti-Alzheimer’s Disease Activity, 2021, 70, 1345-8957, 1133, 10.5650/jos.ess21040
    33. N. Eswaran, S. Parameswaran, T. S. Johnson, 2021, Chapter 20, 978-1-0716-1322-1, 317, 10.1007/978-1-0716-1323-8_20
    34. Timothy Tibesigwa, Brian Iezzi, Tae Hwan Lim, John B. Kirabira, Peter W. Olupot, Life cycle assessment of biodiesel production from selected second-generation feedstocks, 2023, 26667908, 100614, 10.1016/j.clet.2023.100614
    35. Baptiste Vanleenhove, Lin Xu, Steven De Meester, Katleen Raes, Impact of Stabilization Technology on the Extraction Yield and Functionality of Macroconstituents from Biomass: A Systematic Review, 2023, 0021-8561, 10.1021/acs.jafc.3c02148
    36. Miona Stanković, Snežana Kravić, Nebojša Stanojević, Marija Tasić, Vlada Veljković, Biodiesel production from strawberry pomace seed oil, 2023, 12, 2406-2979, 20, 10.5937/savteh2301020S
    37. Getachew D. Gebre, Shemelis N. Gebremariam, Yadessa G. Keneni, Jorge M. Marchetti, Valorization of tropical fruit‐processing wastes and byproducts for biofuel production, 2023, 1932-104X, 10.1002/bbb.2531
    38. Karuna Boppena, Murali Mekala, Lakshmi Prasanna Mallarapu, Rehan Wasi Mohammed, Appala Naidu Uttaravalli, Bhanu Radhika Gidla, Vijay Kanth Addanki, Extraction of rain water tree seed oil: Sustainable applications and management, 2023, 24, 2589014X, 101657, 10.1016/j.biteb.2023.101657
    39. Tafere Aga Bullo, Yigezu Mekonnen Bayisa, Ketema Beyecha Hundie, Desalegn Abdissaa AKuma, Defar Getahun Gezachew, Mohammed Seid Bultum, Optimization, Characterization and Production of Biodiesel from Rumex Crispus Leaves and Roots Oil Using Central Composite Design (CCD), 2023, 2522-5758, 10.1007/s42250-023-00784-3
    40. Asanthi Hippola, Yasasvi Jayakodi, Ashoka Gamage, Terrence Madhujith, Othmane Merah, Nutritional, Functional Properties and Applications of Mee (Madhuca longifolia) Seed Fat, 2023, 13, 2073-4395, 2445, 10.3390/agronomy13102445
    41. Ulrich Cabrel Kenmegne Tebe, Julius Kewir Tangka, Henri Grisseur Djoukeng, Brice Martial Kamdem, Esther Azemo Folepe, Effects of extraction parameters on the yield of oils from non-edible seeds of Bauhinia variegata and Pachira glabra, 2024, 10, 24058440, e30777, 10.1016/j.heliyon.2024.e30777
    42. Jawaher AlYammahi, Houda Chelaifa, Ayesha Hasan, Ahmad S. Darwish, Tarek Lemaoui, Hector H. Hernandez, Alejandro Rios-Galvan, Salicornia seed oil: A high-yielding and sustainable halophytic feedstock for biodiesel and energy in underutilized hypersaline coastal deserts, 2024, 318, 01968904, 118914, 10.1016/j.enconman.2024.118914
    43. Rogers Kipkoech, Mohammed Takase, Arcadius Martinien Agassin Ahogle, Gordon Ocholla, Analysis of Properties of Biodiesel and its Development and Promotion in Ghana, 2024, 24058440, e39078, 10.1016/j.heliyon.2024.e39078
    44. Adem Siraj Mohammed, Venkata Ramaya Ancha, Samson Mekbib Atnaw, Optimization of biodiesel production from Croton Macrostachyus seed oil with calcium oxide (CaO) catalyst and Characterization: Potential assessment of seed and kernel, 2024, 25901745, 100791, 10.1016/j.ecmx.2024.100791
    45. Piyush Vatsha, Md Reyaz Alam, 2025, 9780443214332, 19, 10.1016/B978-0-443-21433-2.00019-0
    46. Arif Savaş, Samet Uslu, Ramazan Şener, Optimization of performance and emission characteristics of a diesel engine fueled with MgCO3 nanoparticle doped second generation biodiesel from jojoba by using response surface methodology (RSM), 2025, 381, 00162361, 133658, 10.1016/j.fuel.2024.133658
  • Reader Comments
  • © 2021 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0)
通讯作者: 陈斌, bchen63@163.com
  • 1. 

    沈阳化工大学材料科学与工程学院 沈阳 110142

  1. 本站搜索
  2. 百度学术搜索
  3. 万方数据库搜索
  4. CNKI搜索

Metrics

Article views(4135) PDF downloads(177) Cited by(6)

Article outline

Figures and Tables

Figures(9)  /  Tables(6)

/

DownLoad:  Full-Size Img  PowerPoint
Return
Return

Catalog