Antioxidant and enzyme-inhibitory properties of sesame seed protein fractions and their isolate and hydrolyzate

Abstract

Sesame seed was defatted and subsequently fractionated into albumin, globulin, glutelin and prolamin. The defatted flour was also subjected to alkaline solubilization and acid precipitation to obtain protein isolate. The sesame seed protein isolate was hydrolyzed using a combination of pepsin and pancreatin to produce the protein hydrolyzate. The defatted flour, protein fractions, isolate and hydrolyzate were evaluated for their amino acid profiles as well as in vitro antioxidant and enzyme inhibitory activities. The results showed that the glutelin fraction had higher amounts of essential amino acid (38.1%) when compared with albumin (35.6%), globulin (31.3%), prolamin (37.1%), protein isolate (37.1%) and protein hydrolyzate (36.7%). The defatted flour exhibited the strongest DPPH radical scavenging activity while only the globulin, isolate and hydrolyzate exhibited superoxide radical scavenging activity. The defatted flour also had the strongest hydroxyl radical scavenging activity of 91.79%, although lower than the 95.93% for the control peptide (glutathione). The hydrolyzate had the strongest metal chelating activity (75.53%), while the isolate had the highest ferric antioxidant reducing power. The albumin was the most effective inhibitor of angiotensin converting enzyme and α-amylase with values of 30.04% and 29.44%, respectively. In contrast, renin activity was strongly inhibited (89.87%) by the isolate but acetylcholinesterase was weakly inhibited by the hydrolyzate (16.89%) and prolamin (16.29%). We conclude that the defatted flour and protein products are potential ingredients that could be incorporated into foods to extend shelf-life but also with potential bioactive properties.

Polypeptide composition of major oilseed proteins and functional properties of extracted protein products: A concise review

“…Unlike most oilseeds, sesame seed protein is rich in sulfur containing amino acids but low in lysine, which makes it a suitable ingredient for supplementing legume proteins (Johnson et al, 1979). A recent report showed that the globulin fraction had the highest level of sulfur containing amino acids at 8.5% when compared to 4.5%, 3.5%, 5.0%, and 4.4% for the albumin, glutelin, prolamin, and the sesame seed protein isolate (SSPI), respectively (Idowu, Famuwagun, et al, 2021). At $15%, the globulin also contained the highest level of arginine when compared to 9%-13% for the other isolated proteins.…”

“…Polypeptide composition of oilseed proteins arise mainly from the four traditional solubility‐based groups, that is, albumin, globulin, prolamin, and glutelin, which are extracted with water, dilute salt solution, aqueous alcohol, and dilute NaOH, respectively (Idowu, Famuwagun, et al, 2021). However, most oilseed proteins are composed essentially of the globulins, which are also sub‐divided into various polypeptide types.…”

Production, Purification, and Potential Health Applications of Edible Seeds’ Bioactive Peptides: A Concise Review

“…The results demonstrate the potential of food-derived peptides in mitigating oxidative reaction-induced damages in biological and food matrices. A recent study by Idowu et al [76] assessed the sesame seed protein hydrolysate produced using pepsin and pancreatin enzymes for their effective antioxidant potential. The results confirmed that sesame seed protein hydrolysate had the highest hydroxyl radical scavenging and metal chelation activity compared to the unhydrolyzed protein.…”

Antimicrobial Activity of Quinoa Protein Hydrolysate against Streptococcus pyogenes and Escherichia coli

“…Tus, providing natural alternatives is of utmost importance. In recent years, characterizing natural antioxidants has received special attention, which leads to studies on antioxidant and antibacterial capacity of peptides derived from hydrolysed proteins of a variety of food resources, e.g., soy protein [2], casein [3], egg white protein [4], seeds of river tamarind [5], sesame seed [6], cowpea [7], Okra seed meal [8], and fsh proteins [9].…”