Study On Producing ACE Inhibitory Peptides From Oat By Liquid-state Fermentation

In this study, the naked oat was fermented using micro organisms to prepare antioxidant peptides and ACE inhibitory peptides, Their process condition was optimized by Response Surface Analysis. The ACE inhibitory were collected, isolated and purified through many methods including Gel column chromatography, Ion exchange chromatography and RP-HPLC. The results were as follows:1. With oat peptide yield and ACE inhibitory as indexes for single factor test, The technology conditions was optimized for producing rapeseed ACE inhibitory peptides through liquid-state fermentation by response surface analysis. Results shows that the optimal conditions are as follows:fermentation time39h, fermentation temperature34℃, and pH9.0, under the above conditions, the ACE inhibitory reached64.05%.2. Anti-oxidative peptide was obtained by fermentation of oat with Bacillus subtilis in this study. The fermentation condition was optimized by response surface methodology, based on the single factor experiments, with oat peptide yield and ACE inhibitory rate as indexes. The result showed the optimum fermentation condition was temperature37℃, time44h and inoculation volume5%, Under this condition, the Anti-oxidative peptide ratio of fermented liquid reached to63.59%.3. Separate and purification oat ACE inhibitory peptides by gel filtration, ion exchange and RP-HPLC, The results shows that oat3main peaks are acquired by gel filtration, the second peak has the highest ACE inhibitory activity,65.54%. Purification the second peak by ion exchange,componentl1to13has the highest ACE inhibitory activity,68.39%. Purification component11to13by RP-HPLC, the highest ACE inhibitory activity is70.12%.