Studies on the Antioxidant Activity of Sesame Protein Hydrolysate

• Main Authors: Tsung-Hao Tang, 唐宗豪
• Other Authors: Bing-Lan Liu
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/14923065559235335671

碩士 === 朝陽科技大學 === 生化科技研究所碩士班 === 100 === Sesame is the commonly used for cooking and has the ability of anticoagulant, antioxidant activity, prevention of cardiovascular disease, and other functions. Enzymatic hydrolysis can used to improve the functional properties of proteins. It has been reported that the extent of proteolytic degradation of food proteins affects greatly the functional properties of the hydrolysates. In this study, the sesame protein was hydrolyzed using tyrpsin, bromelain, or actinase E at pH 7.0 and 50°C for 4 hours. Subsequently, the three different hydrolysates: AH (Actinase E hydrolysate), BH (Bromelain hydrolysate), and TH (Trypsin hydrolysate) were tested for various antioxidative activities, including the trolox equivalent antioxidant capacity (TEAC) assay, inhibition of lipid peroxidation in a liposome model system as well as the Cu2+-induced oxidation of human LDL. The scavenging activity of AH (21.91±2.00%) is better than BH (12.74±1.84%) and TH (7.80±1.36%) in TEAC assay. The TEAC values of AH, BH, and TH, were 0.249±0.013 mM, 0.167±0.074 mM, and 0.104±0.014 mM trolox equivalent, respectively The scavenging activity was increased with hydrolysis time during the first 30 minutes as monitored in SDS-PAGE. No significant scavenging effects were found beyond the 150 minutes hydrolysis. Moreover, the inhibition of malondialdehyde (MDA) by three hydrolysates would reach a plateau of progress after 150 minutes. Among, the AH (12.61±1.08%) and TH (12.70±2.04%) exhibited a better inhibitory activities than BH (9.27±2.04%). The antioxidant capacity for Cu2+-induced oxidation of human LDL was conducted using the AH samples. The formation of conjugated diene within six hours was lower in the case of AH than the non-hydrolyzed sesame protein. This demonstrated that the inhibition of LDL oxidation by sesame protein was more effectiveness after hydrolysis.