Okra seed protein isolate (OSPI) has garnered increasing interest due to its bioactive potential and nutritional value. This research focused on analyzing the structural characteristics and molecular composition of OSPI to evaluate its potential therapeutic applications. The amino acid profile revealed a diverse range of amino acids, with leucine (6.56 g/100 g), glutamic acid (14.46 g/100 g), and arginine (9.42 g/100 g) identified as the most abundant. Hydrophobic amino acids (31.39 g/100 g) along with branched-chain amino acids (14.24 g/100 g) further underscore their bioactivity, particularly in immune modulation and cancer therapy. Protein solubility analysis indicated optimal solubility (91.86%) at pH 9, a key factor influencing bioavailability. The molecular weight profile identified polypeptide bands corresponding to 2S albumins, known for their antimicrobial and immunomodulatory properties. FTIR and XRD analyses highlighted the presence of α-helical and β-sheet structures, contributing to OSPI's functional stability. Additionally, OSPI exhibited an amorphous nature, which is beneficial for pharmaceutical applications due to enhanced bioavailability. Particle size analysis demonstrated a monomodal distribution, with OSPI displaying the smallest size (0.144 ± 0.1 µm), indicative of improved drug delivery potential. Collectively, these findings emphasize OSPI's therapeutic potential, particularly in disease prevention and treatment, supporting its potential application in pharmaceutical and nutraceutical industries.
Citation: Letisha Maistry, Abe Shegro Gerrano, John Mellem. Chemical and structural characterization of okra (Abelmoschus esculentus) seed protein isolate as a potential therapeutic agent[J]. AIMS Agriculture and Food, 2025, 10(2): 353-370. doi: 10.3934/agrfood.2025018
Okra seed protein isolate (OSPI) has garnered increasing interest due to its bioactive potential and nutritional value. This research focused on analyzing the structural characteristics and molecular composition of OSPI to evaluate its potential therapeutic applications. The amino acid profile revealed a diverse range of amino acids, with leucine (6.56 g/100 g), glutamic acid (14.46 g/100 g), and arginine (9.42 g/100 g) identified as the most abundant. Hydrophobic amino acids (31.39 g/100 g) along with branched-chain amino acids (14.24 g/100 g) further underscore their bioactivity, particularly in immune modulation and cancer therapy. Protein solubility analysis indicated optimal solubility (91.86%) at pH 9, a key factor influencing bioavailability. The molecular weight profile identified polypeptide bands corresponding to 2S albumins, known for their antimicrobial and immunomodulatory properties. FTIR and XRD analyses highlighted the presence of α-helical and β-sheet structures, contributing to OSPI's functional stability. Additionally, OSPI exhibited an amorphous nature, which is beneficial for pharmaceutical applications due to enhanced bioavailability. Particle size analysis demonstrated a monomodal distribution, with OSPI displaying the smallest size (0.144 ± 0.1 µm), indicative of improved drug delivery potential. Collectively, these findings emphasize OSPI's therapeutic potential, particularly in disease prevention and treatment, supporting its potential application in pharmaceutical and nutraceutical industries.
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