114F-1 |
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S. Y. XU1, Z. Wang2, and F. Zhou2. (1) School of Food Science & Technology, Southern Yangtze University, 170 Huihe Rd., Wuxi, Jiangsu Province, 214036, China, (2) School of Food Science and Technology, Southern Yangtze University, 170# Huihe Road, Wuxi, 214036, China China has abundant waste silk source, which is a by-product of silk processing. Silk is mainly composed of silk fibroin and silk fibroin peptides are the hydrolysates of silk fibroin. Silk fibroin peptides can be used as functional food and medicine. In addition, silk fibroin peptides are excellent cosmetic additives. So the peptides will have an intriguing prospect of utilization. The objective of this study is mainly to prepare Bombyx mori silk fibroin peptides from waste silk. A new suitable method for preparation of silk fibroin peptides on a pilot plant scale was developed. Silk fibroin obtained from waste silk was refined in 0.5% (w/v) sodium carbonate solution, then dissolved in 40% (w/w) calcium chloride solution. The dissolved silk fibroin was hydrolyzed by Alcalase 2.4l, an industrial and food grade enzyme, then desalted by using nanofiltration technology. Finally silk fibroin peptide powder was obtained by spray drying the desalted solution. Several enzymatic hydrolysates of silk fibroin with different degrees of hydrolysis (DH) were tested for their inhibitory activity for angiotensin I-converting enzyme (ACE) by using RP-HPLC. The structures of ACE inhibitory peptides were determined by using LC/MS. Appropriate operating pressure and temperature of nanofiltration were 1.0MPa and 35 degree(C) respectively. After the process, the desalted rate was 98%, and the silk fibroin peptide recovery rate was 72%. The product of peptides obtained from the hydrolysates with DH18% had higher ACE inhibitory activity. The concentration of silk fibroin peptides providing 50% inhibition of ACE was 0.5mg/mL. Result showed that dipeptide and tripeptide had higher ACE inhibitory activity. These results demonstrate that the new technology for preparation of silk fibroin peptides on a pilot plant scale is efficient. The bioactive peptides from silk fibroin will provide a new resource of functional food.
Session 114F, Nutraceuticals & Functional Foods: Processing and physical properties
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