The Modulatory Effect of Cholesterol Synthesis by Oryza sativa Derived Bioactive Peptide Fractions: An In Vitro Investigation

Abstract

A primary risk factor of cardiovascular disease is referred to the high concentration of plasma cholesterol. The alleviation of plasma cholesterol and inhibition of the catalytic domain of human 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), provides an alternative therapeutic candidate for reducing cholesterol. The present study evaluates the impact of rice bran protein hydrolysate (RBPH) on cholesterol homeostasis. The RBPH was produced by in vitro digestion of the extracted protein using commercial pepsin and pancreatic enzymes under optimized conditions. The hydrolysate was subjected to RP-HPLC and LC–MS profiling indicating three major peaks having masses ranging from 120 to 903 m/z. The degree of hydrolysis for producing the bioactive peptides has been marked with 61.53 ± 0.36%. SDS-PAGE reveals resistance to digestion compared to the native protein extracted from rice bran. The RBPH regulates the cholesterol level in two ways, the first potential role is by restricting the recycling of bile salts to the liver via direct excretion, second by exhibiting maximum micellar cholesterol inhibitory capacity and HMGCR inhibition in a dose dependent manner. The modulatory effect of RBPH on cholesterol homeostasis suggests hypocholesterolaemic property which could find an excellent application in developing physiological functional foods.