Preparation,Bioactivity And Gelatinization Of Polyphenols From Nymphaea Candida

Objective:The resources of plants in genus Nymphaea are rich.And the plants in genus Nymphaeaare mostly distributed in temperate,tropical and subtropical regions.Not only because of their rich flowers and colors,but also their rich nutrients and diverse biological activities,the plants in genus Nymphaeaare have certain development value in food field and medical application.At present,as a medicinal and edible plant,Nymphaeaare have good economic benefits,because of their rich nutritional value and high yield.Nymphaea candida is a characteristic plant in Xinjiang.In recent years,their has attracted people's attention for its good nutritional value and medicinal effects.And has begun artificial cultivation.In order to development and application of N.candida,based on the foundation of previous research,the purpose of this study was to prepare polyphenols extracts from N.candida with high purity and good stability.Then we researched their antioxidant,antibacterial and anti-inflammatory activities.And we researched the preparation process and quality control of polyphenols gel using polyphenols extracts.The results can provide reference for the further development of N.candida.Methods:Using yields of total polyphenols and isostrictiniin as index,the optimal extraction process of polyphenols from N.candidas was determined by single factor test combined with orthogonal experimental design.We purified the polyphenols extracts by D101 macroporous adsorption resin combined with polyamide resin.We investigated the initial stability of polyphenols extracts by high temperature test,high humidity test and light test.And we evaluated the antioxidant ability of polyphenols extracts by Fe³⁺reduction ability,FRAP method,scavenging DPPH·test and POV value determination.The inhibitory activities of polyphenols extracts on Escherichia coli,Staphylococcus aureus,Salmonella enterica and Pseudomonas aeruginosa were investigated by enzyme-labeled instrument.The anti-inflammatory activity of polyphenols extracts was evaluated by the model of auricle swelling induced by xylene in mice.To select the optimal fomulation,we applied the comprehensive score of the appearance,spreading,stability and viscosity of polyphenols extracts gel as the index by single factor test combined with orthogonal experimental design.Results:The optimum technological conditions for the extraction of polyphenols from N.candida were as follows:the ethanol concentration was 50%,feed-liquid ratio was 1:50 g/m L,ultrasonic temperature was 60?,extraction time was 40 min,ultrasonic power was 90 W,in which the effect of feed-liquid ratio was significant.And the purification by D101 macroporous adsorption resin combined with polyamide resin can significantly improve the content of total polyphenols and isostrictiniin in polyphenols extracts.The polyphenols extracts from N.candida had good stability under the conditions of 40?,RH 75%and luminous intensity 4500 lx±500 lx.The antioxidant ability of polyphenol extracts was in a dose-dependent manner.The DPPH·scavenging ability and Fe³⁺reduction ability of polyphenols extracts were better than vitamin C.The total antioxidant abilities of polyphenols extracts and vitamin C were equal.The polyphenols extracts had a certain antioxidant effect on sunflower seed oil,rapeseed oil and lard.The antioxidant activity on lard of 0.02%polyphenols extracts combined with 0.02%TBHQ or 0.02%Vit C or 0.02%citric acid was higher than that of 0.02%polyphenols extracts itself.And the antioxidant activity on lard of0.02%polyphenols extracts combined with Vit C was the best.The results of antimicrobial activity of polyphenols extracts showed that the inhibitory effect on Escherichia coli,Staphylococcus aureus,Salmonella enterica were weak at 128?g/m L,but the inhibitory effect on Pseudomonas aeruginosa was strong at 128?g/m L.The results of anti-inflammatory activity of polyphenols extracts showed that polyphenols extracts could effectively inhibit the acute inflammation of auricle swelling induced by xylene in mice.The single factor tests combined with orthogonal experimental design were applied to optimize the preparation process of polyphenols extracts gel.0.4g carbomer-940 was full swelling in double distilled water.And 0.75g polyphenols extracts from N.candida were dissolved with 2m L propylene glycol and 4m L anhydrous ethanol.The two solutions were mixed.And 0.1g ethyl hydroxybenzoate,15g glycerol,10g propylene glycol and 1.5m L 1%azone solution were added into the mixed solutions.Then the mixed solutions were adjusted p H to 5.0 with 9m L 2.5%triethanolamine solution.At the end,the mixed solutions were added double distilled water to 100g and kept stirring with a magnetic stirrer.Conclusion:The ultrasonic extraction process can obviously improve the extraction effect of polyphenols from N.candida.The antioxidant activity of the polyphenols extracts from N.candida provide a scientific basis for their to become a new food additive,and their strong antibacterial,anti-inflammatory activities,and the preparation process of polyphenols extracts gel is easy,and the quality control methods of the gel is sample.The results have laid a solid foundation for the further development and application of polyphenols extracts from N.candida.