The Study On Preparation Technology And Hypoglycemic Effect Of Momordica Charantia L.

The Momordica Charantia L.(bitter gourd) is one of of the vegetables with a long planting history,which is highly valued as a pharmaceutical/food resource around the world throughout the ages. Most importantly, in terms of regulating blood sugar of the diabetics, it demonstrates remarkable effect.Therefore, the research on the bioactivators of Momordica Charantia L truly has both theoretical and practical significance. In the present research, bitter gourds with different varieties and maturity degrees were selected according to the contents of flavonoids and saponins, and then traditional ethanol-extraction process and freezing and thawing technology were studied for getting different extractives. Finally, the glucose-reducing effects of these extractives were compared to each other with acarbose as positive control, taking the inhibition ratios to alpha glycosidase enzymes and alpha amylase as indicators. The results showed that:1. During the storage of bitter gourds, the changes of a-value,H-value and h-value were associated with the content changes of saponins and flavonoids to a certain extent.The smaller the colour parameters were,the bigger the contents were. In terms of the variety,"Chunxiao NO.4"and "Chinese leader"were respectively dominant on the content of saponins and flavonoids, while the stability of these contents was much higher in "Qingpi"than in the others.2. The optimal conditions for extracting saponins and flavonoids from bitter gourds,with the aid of ultrasonic wave,were80%ethanol concentration solid-to-liquid ratio1:25,70℃, and40min.The gradation of effect for saponnins was solid-to-liquid ratio> extracting time> extracting temperature> ethanol concentration, while for flavonoids it was:ethanol concentration> extracting time>extracting temperature> solid-to-liquid ratio.3. The optimal conditions for freezing and thawing bitter gourds to get the powder were5%salt content, slice thickness0.5cm, freezing temperature-12℃and freezing times once. Besides, the optimal conditions for extracting saponins and flavonoids from the juice powder,with the aid of ultrasonic wave, were80%ethanol concentration, solid-to-liquid ratio1:15,50℃and40min.4. The content of saponins and flavonoids in bitter gourds juice powder was fairly higher than that in general ethanol extracts from bitter gourds.The content of saponins was5.1times bigger than that of the latter one,while the ratio for flavonoids was2.37:1.5. Both alpha glycosidase enzymes and alpha amylase could be inhibited by extractives from bitter gourds,and the inhibition ratio was climbing with the concentration of extractives increasing.Moreover,the inhibiting effect of bitter gourds juice powder to alpha glycosidase enzymes was close to that of acarbose, which belonged to noncompetitive inhibition. However,the inhibiting effects of all the bitter gourds extractives were visibly weaker than that of acarbose.