Comparative Study Of Pea And Other Leguminous Proteins On Cholesterol Lowering Activity,Structural And Functional Properties

Legumes protein is considered highly nutritious,good functional properties and physiological activities.Recently,protein hydrolysates have attained great attention due to a good nutritive food ingredient and higher biological activities.Bioactive peptides are generally obtained from plant protein hydrolysates.They are proposed to possess physiological activities such as lowering blood cholesterol.In the current study,different legumes protein and its hydrolysates(mung,adzuki,faba,kidney bean and pea)were used to study their functional properties,structural and efficiency of cholesterol lowering bio-activity.Total amino acids(TAA)in mung and faba bean proteins were higher as compared to pea,adzuki bean and kidney bean while,pea had lowest hydrophobic amino acids(HAA)than other legumes.Adzuki bean protein exhibited the lowest emulsifying and foaming properties.The IR and CD spectra of kidney bean protein showed less concentration of ?-helix,?-sheets and random coil.Mung and faba bean protein exhibited higher degree of hydrolysis and showed significant(p<0.05)higher inhibition of in vitro cholesterol solubility(24.28±0.56% and 30.29±0.81%,respectively)than adzuki,white kidney bean and pea protein.The inhibition of cholesterol solubilization into micelles and 3-hydroxy-3-methylglutaryl coenzyme-A reductase(HMG Co-AR)catalytic activity was evaluated by < 3kDa hydrolysates from faba bean and adzuki bean protein.High performance liquid chromatography(HPLC)results showed higher concentration of peptides after thermal processing in faba bean.After processing,peptides from faba bean showed significantly(p < 0.05)higher inhibition of cholesterol solubilization into micelles(45.1%±1.6),while peptides from native faba bean protein exhibited significantly higher(p < 0.05)inhibition of HMG Co-AR catalytic activity(84.1%±2.7)as compared to adzuki bean and thermally processed peptides.After processing,peptides from adzuki bean showed significantly lower scavenging activity than the peptides obtained from native protein.Thermosonication,ultrasound and heat were used as a pre-treatment to obtain(<3KDa)hydrolysate from mung bean and white kidney bean to understand the mechanism of cholesterol absorption into micelle and inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase(HMG-CoA)activity.Size exclusion high performance liquid chromatography(SE-HPLC)results of mung bean showed that the concentration of peptides(0.5KDa-1KDa and 1-3KDa)in the hydrolysate were significantly(p<0.05)increased after thermosonication while,the peptides concentration(1-3KDa)in white kidney bean was significantly(p<0.05)decreased.Thermosonication of mung bean hydrolysate exhibited higher inhibition of cholesterol solubilization,hydrophobicity and antioxidant activities.In addition,there was no difference observed in HMG-CoA activity and hydrophobicity between ultrasound alone and ultrasound combined with heat i.e.thermosonication treated hydrolysate of white kidney bean.Changes in secondary and tertiary structures were also analysed under different processing conditions with maximum change due to thermosonication.These findings indicated that mung and faba bean protein have good potential for cholesterol lowering,functional and structural properties,which can be helpful for food and nutraceutical industries.