Xiuming Wang1, Haixia Chen1, Shuqin Li1, Jiangchao Zhou1, Jiangtao Xu1. 1. Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300072, P. R. China.
Abstract
BACKGROUND: Some food proteins hydrolysates are found to possess multiple health effects. In this study, walnut protein (WP) was enzymatically hydrolysed by alcalase and trypsin under optimal conditions. The physico-chemical properties, antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of WP, alcalase-generated walnut protein hydrolysate (AWPH) and trypsin-generated walnut protein hydrolysate (TWPH) were comparatively studied. Stability properties of the walnut protein hydrolysate (WPH) and the antihypertensive activity in spontaneously hypertensive rats (SHRs) were also investigated. RESULTS: The WPH showed higher physico-chemical properties, antioxidant activities, ACE inhibitory activity and stability against thermal treatment and gastrointestinal digestion than WP. The results of antihypertensive effects in SHRs showed that the most potent decrease of AWPH and TWPH in the systolic blood pressure occurred at 4 h (-26 mmHg) and 6 h (-30 mmHg) after administration. The study indicated that the WPH could significantly decrease the systolic blood pressure (P < 0.05). CONCLUSION: The WPH exhibited high physico-chemical properties, potent inhibitory activities and high stability. TWPH was more effective than AWPH in the detected properties. The results would be helpful for the comprehensive utilisation of the walnut resources.
BACKGROUND: Some food proteins hydrolysates are found to possess multiple health effects. In this study, walnut protein (WP) was enzymatically hydrolysed by alcalase and trypsin under optimal conditions. The physico-chemical properties, antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of WP, alcalase-generated walnut protein hydrolysate (AWPH) and trypsin-generated walnut protein hydrolysate (TWPH) were comparatively studied. Stability properties of the walnut protein hydrolysate (WPH) and the antihypertensive activity in spontaneously hypertensiverats (SHRs) were also investigated. RESULTS: The WPH showed higher physico-chemical properties, antioxidant activities, ACE inhibitory activity and stability against thermal treatment and gastrointestinal digestion than WP. The results of antihypertensive effects in SHRs showed that the most potent decrease of AWPH and TWPH in the systolic blood pressure occurred at 4 h (-26 mmHg) and 6 h (-30 mmHg) after administration. The study indicated that the WPH could significantly decrease the systolic blood pressure (P < 0.05). CONCLUSION: The WPH exhibited high physico-chemical properties, potent inhibitory activities and high stability. TWPH was more effective than AWPH in the detected properties. The results would be helpful for the comprehensive utilisation of the walnut resources.