Effect of Proteolysis and Lactic Acid Bacteria Fermentation on the Biofunctionality of Soybean

• Main Authors: Cheng, Pei-Wen, 程姵雯
• Other Authors: Jiang, Shann-Tzong
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/44822564223339911723

碩士 === 靜宜大學 === 食品營養學系 === 102 === Recently many studies indicated that many peptides and antioxidants with inhibiting angiotensin converting enzyme (ACE) activity were from a variety of plant and animal proteins after appropriate processing. This study aimed to investigate the effect of proteolysis and lactic acid bacteria fermentation on the biofunctionality of soybean. The proteases from Bacillus subtilis YJ9 (16000 U / mL) were employed to hydrolyze soy protein. The resulted samples were further fermented with lactic acid bacterium (LAB, Lactobacillus acidophilus BCRC17009) for 24 h. Changes in soluble proteins, peptides, free amino acids, isoflavones, and other physiological functionality were determined. It was found that 10 h hydrolysis combined with 24 h LAB fermentation of soybean hydrolysate had significant higher contents (P<0.05) of soluble proteins, peptides, free amino acids, antioxidant capacity (EC50 = 2.30 mg / mL), and higher human gastrointestinal tract tolerance, and lower concentration to inhibit 50 % activity of ACE (IC50 = 0.58 mg / mL), compared with those without hydrolysis / LAB fermentation sample. The data obtained suggested that increase of proteolysis time could substantially increase its soluble proteins, peptides, free amino acids and other physiological functionality. However, no significant differences in those parameters was observed between proteolyzed sample and those with proteolysis combined with LAB fermentation.