Title : Production of ACE-I inhibitory and antioxidant peptides resistant to gastrointestinal digestion from orange seed protein by pepsin enzyme
Abstract:
Introduction: The use of enzymes for hydrolysis of protein sources is one of the common methods in the food processing. A hydrolysed protein is a complex mixture of peptides and amino acids that are obtained from hydrolysis by various enzymes, acids or alkali. These hydrolysed proteins and peptides have important biological role including anti-oxidation, antimicrobial, anti-diabetict, anti-cancer, anti-hypertensive, influencing the immune system, nervous system and digestive system. The orange seed is largely available from the waste of the juice industries, and its defatted flour has about 26% protein and can be used as a rich and cost-effective source for the production of proteins and peptides of plant sources.
Method: The aim of the present study was to hydrolyse orange seed proteins by Pepsin enzyme (protease from porcine gastric mucosa) to obtain bioactive peptides with high antioxidant activity and ACE-inhibitory activity. In order to do further identification and isolation of bioactive peptides, molecular weight distribution and fractionation of hydrolyzed proteins were performed using SEC and then isolation and purification of the most active fractions obtained in the previous step, was performed by RP-HPLC and finally sequencing and identification of the resulting peptide fractions were performed using NanoLC-MS / MS. Peptide fractions were also subjected to simulated gastrointestinal digestion and the most active fractions in terms of antioxidant activity and antihypertensive potential were isolated and purificated using RP-HPLC and finally using NanoLC-MS / MS peptide fractions were sequenced and identified. Thus, the method was optimised using different enzyme concentrations (1-3%),hydrolysis times(2-5h) in optimal temperature of 33°C.
Result: The results showed the highest bioactivity of pepsin hydrolyzed treatments in the optimum treatment gained using the ratio of 2 w/w of enzyme to substrate concentration and hydrolysis time was 3.5 h at 35 ° C (p<0.05). The SEC profile of the pepsin hydrolysates contained three major peaks corresponding to the proteins with molecular weights of 70,000 daltons, 13,000 daltons, and 1420 daltons. The most active fractions obtained from SEC hydrolyzed Pepsin proteins, were seprated by RP-HPLC separation and resulted chromatogram showed a mixture of hydrophilic and hydrophobic peptides. Generally, relatively hydrophobic peptides and high hydrophobic peptides showed the highest bioactivity in the hydrolysates produced by Pepsin enzymes. The results obtained after simulated gastrointestinal digestion showed that some of the peptide fractions obtained after chromatographic separation significantly retained their biological activity and F32 fractions obtained from hydrolyzed Pepsin was more resistant to gastrointestinal digestion than other peptide fractions.
Conclusion: Generally, the orange seed can be used to produce hydrolyzed proteins and bioactive peptides with high healthful and resistant to digestion properties. Finally, a useful product with the ability to lower blood pressure, as a food drug, is a suitable solution for the prevention and treatment of hypertension. And since cardiovascular diseases are one of the most important causes of human mortality in the worldwide, these bioactive peptides can be used as a natural food product having a high potential to enhance the health-related quality of life. My research achievements were three national patents and one international patents, as well as,Using my unique and advanced expertise, I was able to obtain a license to produce these products with health effects from the Iran Food and Drug Administration with the aim of commercial production of these functional products.
Keyword: Peptides; Orange Seed; Antioxidant; ACE-I Inhibitory; Gastrointestinal Digestion.
Audience Take Away
- A useful product with the ability to lower blood pressure, as a food drug, is a suitable solution for the prevention and treatment of hypertension.
- since cardiovascular diseases are one of the most important causes of human mortality in the worldwide, these bioactive peptides can be used as a natural food product having a high potential to enhance the health-related quality of life.
- My research achievements were three national patents and one international patents, as well as,Using my unique and advanced expertise, I was able to obtain a license to produce these products with health effects from the Iran Food and Drug Administration with the aim of commercial production of these functional products.
