Study On Microwave Assistant With Enzyme Extraction Process And Antioxidant Of Lotus Seed Epicarp

Lotus seed epicarp is one of the inedible parts of lotus,which grows from green into brown and become more and more hard during maturation.In this paper,lotus seed epicarp in mature stages were used as the materials to study the conditions of ultrasonic extraction,the antioxidant activities and antimicrobial activity.The main results of this research were as follows:1.The microwavemi extraction conditions of lotus seed epicarp polyphenols in were optimized by four-factor and three-level orthogonal experiment.To lotus seed epicarp polyphenols,the best extraction conditions were ethanol concentration 50%,microwave power 700 w,extraction time 50s,solid-liquid rato 1:25.Under the optimal conditions,yields of lotus seed epicarp polyphenols were7.71%.We also confirmed that polyphenols was not damaged by microwavemi extraction.2.The cellulase extraction conditions of lotus seed epicarp polyphenols in were optimized by four-factor and three-level orthogonal experiment.To lotus seed epicarp polyphenols,the best extraction conditions were extraction temperature 40?,volume of enzyme 2%,extraction time 60min,solid-liquid rato 1:20.Under the optimal conditions,yields of lotus seed epicarp polyphenols were7.14%.We also confirmed that polyphenols was not damaged by cellulase extraction.3.Using tea polypheno(TP)as the comparison,The antibacterial action of lotus seed epicarp polyphenols was studied.The result shown that lotus seed epicarp polyphenols have a notable inhibiting microorganism activity against Escherichia coli?Staphylococcus aureus?Salmonella choleraesuis?Listeria monocytogenes but it have no antibacterial activity against Streptococcus lactis.In addition,the MIC for four kinds of bacterias were as follow:to lotus seed epicarp polyphenolic,Staphylococcus aureus and Listeria monocytogenes,0.4mg/ml,Escherichia coli and Salmonella choleraesuis,0.5mg/m;to preliminary purification polyphenols,Staphylococcus aureus,0.3 mg/m L,Escherichia coli,Salmonella choleraesuis,Listeria monocytogenes 0.4 mg/m L;to purification polyphenols,Escherichiacoli,0.4mg/m,Staphylococcusaureus,Salmonella choleraesuis,Listeria monocytogenes,0.3mg/ml.Meanwhile,changing temperature within limits could have little affect the antibacterial activity of lotus seed epicarp polyphenols,and the antibacterial effect of lotus seed epicarp polyphenols has better antibacterial effect in the p H6-7.Improving the concentration of Inorganic salt have no affect on the antibacterial activity.4.Using lactic acid bacteria as the fermentative strain,the antioxygenation of lotus seed epicarp polyphenols was studied.The results showed that the fermentation can improve the the antioxygenation of lotus seed epicarp polyphenols:after 24h‘s fermentation,the scavenging abilities on ABTS~+increased by-0.28%?14.97%,scavenging abilities on DPPH increased by 15.13%?25.32%,the scavenging ability increased by-1.06%?4.37%;after 48h‘s fermentation,the scavenging abilities on ABTS~+increased by 4.29%?17.02%,the scavenging abilities on DPPH increased by 16.58%?22.58%,the scavenging ability increased by-1.76%?11.31%.