| Mungbean sprouts is a traditional Chinese vegetable,it not only contains rich nutrition, but also has important medicinal value.In this paper,mungbean sprouts as the research object, the extraction conditions were selected and the dynamic content of total flavonoids in germinative mungbean was analyzed, at the same time its antioxidative functions were studied.The results were showed as following:1. Organic solvent extraction,through the analysis of the single factors and the optimization of the orthogonal experiment,the best optimal technological requirement to extract total flavoids from mungbean sprout was that ethanol concentration was 70%,the ratio of solid to liquid was1g:15mL,extracting temperature was 70℃and extracting duration was 2.5h.At this condition,the yield rate of total flavonoids was 0.685%.2. Ultrasonic wave extraction,through the analysis of the single factors and the optimization of the orthogonal experiment,the best optimal technological requirement to extract total flavoids from mungbean sprout was that ethanol concentration was 60%,the ratio of solid to liquid was1g:25mL,ultrasonic extracting temperature was 60℃and ultrasonic time was 100min.At this condition,the yield rate of total flavonoids was 0.602%.3.Enzymatic extraction,cellulase was used to extract total flavoids from mungbean sprout, through the analysis of the single factors and the optimization of the orthogonal experiment,the best optimal technological requirement was that enzyme concentration was 0.6mg/mL,pH of enzyme solution was 4.8,enzymatic hydrolysis temperature was 55℃and the time of enzymatic hydrolysis was 2 hours.At this condition,the yield rate of total flavonoids was 0.612%.4. Microwave extraction,through the analysis of the single factors and the optimization of the orthogonal experiment,the best optimal technological requirement to extract total flavoids from mungbean sprout was that ethanol concentration was 80%, microwave power is 400W, extraction time 180 seconds,and the ratio of solid to liquid was1g:40mL,.At this condition,the yield rate of total flavonoids was 0.580%.5.The results among four extraction methods were analyzed with DPS data processing system showed that a very significant difference of organic solvent extraction and other methods,so organic solvent extraction was the best method to exract the total flavonoids of mungbean sprout.6. During the germination of mungbean,we took the samples every other 1 days, organic solvent extraction was used to exact the total flavonoids of mungbean sprouts. It can be seen from analysis that the yield rate of total flavonoids increased gradually with the prolongation of time; and the mungbean sprouts of the fourth day showed the most edible value,combining the change trend of total flavonoids and germination state of mungbean.At this time, mungbean sprouts was strong, it had good taste and grew about 5-7cm., meanwhile the yield rate of total flavonoids was 0.686%.7.1t can be seen from the results of antioxidant experiment in vitro that the extraction of flavonoids from mungbean sprouts had some reducing power and scavenging ability on NO2-free radicals;it had strong scavenging ability on DPPH free radicals and hydroxyl radicals,the clearance on the DPPH free radicals was 86.9% and the clearance on the hydroxyl radicals was 51.8% when the concentration of flavonoids was 0.5mg/mL; the scavenging ability on superoxide radicals was increased with the increase of concentration, the clearance on the hydroxyl radicals was 83.3% when the concentration of flavonoids was 0.25mg/mL;the restraining ability of flavonoids on lipid peroxidation were strong, when its concentration is lower,its activity of scavenging lipid peroxidation was stronger than that of Vc, however, when its concentration is higher,its activity of scavenging lipid peroxidation was lower than that of Vc.These research results showed that the extraction of total flavonoids from mungbean sprouts had good antioxidant capacity.
|
PDF Full Text Request