Effects Of Total Flavonoids Of Portulaca Oleracea L. And Its Endophytic Bacteria On Intestinal Microbiota In Type Ⅱ Diabetic Mice

Objective: Type Ⅱ diabetes mellitus(T2DM)is the most common diabetes mellitus and the proportion is over 90%.In recent years,studies have shown that the intestinal microbiota is closely related to the occurrence of T2 DM,which implied a new way to the prevention and treatment of T2 DM.Current therapeutic drugs have a variety of toxic side effects and adverse reactions,resulting in a limited application.Traditional Chinese medicines have the characteristics of multi-target,small toxic and side effects,and have huge potentials in prevention and cure of T2 DM and its complications.On the other hand,over exploitation of natural medical plants may damage the surrounding ecological environment.Therefore,scientists started with the endophytic bacteria in plants,as a coevolutionary species,for the synthesize active components similar to those of host plants,which may have potential abilities to replace the medicinal plants.This is another way solve the shortage of medicinal plant resources.Methods: In this experiment,Portulaca oleracea L.was used as the research object,the type Ⅱ diabetes mellitus animal model was established by STZ.1.Extraction the total flavonoids in Purslane,and lavage type Ⅱ diabetes mellitus mice.High throughput sequencing technology was used to investigate the therapeutic effects of total flavonoid extracts from purslane on STZ-induced type Ⅱ diabetic mice and its relationship with intestinal microbiota.2.To isolate the endophytic bacteria of Purslane and investigate the inhibitory effect of its metabolites on glucosidase in vitro.Results: 1.Purslane total flavonoids can improve the body weight of T2 DM mice,but the effect is weak.It also reduced the blood glucose levels of animal model and improved glucose tolerance,the effect strengthening with dose.Based on the analysis of the composition of intestinal microbiota at the level of phylum,order and family,it can be known that Increased F/B ratio in intestinal microbiota of type Ⅱ diabetic mice.The content of Enterobacteriaceae and Lachnospiraceae increased,while the content of Bacteroidales＿S24-7＿group decreased.2.A total of 36 strains of Purslane endophytic bacteria were isolated and purified,and one of them,named as PO-S1,showed an inhibition rate of 60.4% against α-glucosidase.Different concentration of the bacteria extracts and the fermentation solutions were used to treat the animal model.After 30 days,we found that PO-S1 improved the weight loss of T2 DM mice,reduced the blood glucose level significantly,and can improve the tolerance of glucose,the middle dose group of bacterial solution had the best effect.This study provided a new approach to the treatment of diabetes with natural products.The isolated strain PO-S1 showed high inhibition of α-glucosidase,animal experiments showed that PO-S1 can increase the body weights in type Ⅱ diabetic mice,and reduce the blood glucose and improve the glucose tolerance level,which will provide a scientific basis for its further development and utilization.