Antioxidant and digestive enzyme inhibitory effects of Eisenia bicyclis extracted by different methods
The antioxidant and digestive enzyme inhibitory effects of Eisenia bicyclis extracted by various extraction methods (RE, reflux extraction; SE, ultrasonification extraction; AE, autoclave extraction; LE, low-temperature high-pressure extraction) were investigated. The extraction yield (55.21%) and the laminarin (39.03%), fucoidan (24.75%), total polyphenol (115.68 mg GAE/g) and flavonoid (36.67 mg RHE/g) contents of AE were higher than those in other methods. The DPPH radical (86.60%, 500 mg%), ABTS radical (58.56%, 25 mg%), nitrite (86.38%, 100 mg%) scavenging activities of the Eisenia bicyclis extracted by AE were higher than those of Eisenia bicyclis extracted by other methods. The ABTS radical and nitrite scavenging activities were above 98% in all tested Eisenia bicyclis extracts and these activities were dependent on its concentration. The inhibitory effects of AE against amylase (50 mg%) and α-glucosidase (5 mg%) were 64.76% and 86.71%, respectively. The AE showed the best inhibitory effect of Eisenia bicyclis extracts (50 mg%) against trypsin (24.37%) and α-chymotrypsin (49.05%), respectively. These results suggest that Eisenia bicyclis extracted by AE can be used as a bioactive and functional material in the food industry.