Preclinical Evaluation of the Antidiabetic Effect and Phytochemical HPLC-MS ESI-QTOF Analysis of Sclerocarya birrea (A. Rich) Hoscht Bark of Trunk Aqueous Extract in Alloxan-Induced Diabetic Wistar Rat

Introduction: Diabetes is a serious public health problem requiring complex treatment. Numerous ethnopharmacological studies have reported the traditional use of Sclerocarya birrea in managing diabetic patients. This study aims to demonstrate, preclinically, the antidiabetic effects of the aqueous decoction of S. birrea trunk bark. Methods: Phytochemical analysis was performed by HPLC-MS. The effects of the extracts (Sb5 and Sb25) and 0.9% NaCl on the normal blood glucose levels of the animals were determined. Diabetes induction was performed intraperitoneally by administering a single dose of alloxan (150 mg/kg) in normoglycemic rats. The antidiabetic effects of the extracts (Allox + Sb5, Allox + Sb25) and glibenclamide (Allox + Glib5) were determined in Alloxan-induced diabetic animals for four weeks. Results: Interpretation of mass spectra obtained by HPLC-MS allowed the tentative identification of vanillic acid-4-sulfate and rhamnetin in Sb extract. Investigated doses of Sb extract showed an antidiabetic impact similar to the reference, glibenclamide, with a return to normal blood glucose in all treated rats only after 4 days of treatment. Furthermore, Sb extract treatments reduced weight loss in diabetic rats. Sb had no negative impact on the balance of total cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL). Conclusion: The present study demonstrated the antidiabetic efficacy and, to some extent, the beneficial effects of Sb extract on Alloxan-induced diabetic rats’ health. Detection of antidiabetic phytochemicals such as vanillic acid-4-sulfate and rhamnetin would justify this pharmacological property of the aqueous decoction of S. birrea trunk bark.

Triterpenoids from Uncaria rhynchophylla and Their PTP1B Inhibitory Activity

Uncaria rhynchophylla(Gouteng)is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China.In this study,the ethyl acetate(EtOAc)part of U.rhynchophylla was revealed with protein tyrosine phosphatase 1B(PTP1B)inhibitory activity.Subsequent investigation on the EtOAc part yielded one new triterpenoid,3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid(1)and four known ones,3β,6β,19α-trihydroxyurs-12-en-28-oic acid(2),2-oxopomolic acid(3),3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid(4)and sumaresinolic acid(5).The structure of compound 1 was determined by extensive HRESIMS,IR,1D and 2D NMR spectroscopic analyses.Two ursane-type triterpenoids(2 and 3)showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7μM.The enzyme kinetic study suggested that compounds 2 and 3 were mixtype inhibitors on PTP1B with Ki values of 15.6 and 132.5μM.This investigation manifests the antidiabetic potency of U.rhynchophylla with triterpenoids as the active constituents.

Hypoglycemic and Hypolipidemic Effects of Lycium barbarum Polysaccharide in Diabetic Rats

Objective To study the antidiabetic effects and the underlying molecular mechanisms of Lycium barbarum polysaccharide（LBP） and its DEAE cellulose elution fraction LBP-IV in diabetic rats induced by high fat diet（HFD） and streptozotocin（STZ）. Methods After ig administration of LBP-IV [50, 100, and 200 mg/（kg·d）] and LBP [100 mg/（kg·d）] once daily for consecutive 4 weeks to diabetic rats, the glucose and lipids in blood, m RNA expression of phosphoenolpyruvate carboxykinase（PEPCK）, sterol regulatory element binding-protein-1c（SREBP-1c）, and fatty acid synthase（FAS） in liver were determined. Results Ig administration of LBP and LBP-IV significantly decreased the levels of blood glucose, Hb A1 c, TC, TG, and LDL-C, as well as the hepatic m RNA expression of PEPCK, SREBP-1c, and FAS, whereas significantly increased the oral glucose tolerance of diabetic rats. Conclusion The findings suggest that the antidiabetic effects of LBP and LBP-IV are associated with the decreased hepatic m RNA expression of PEPCK, SREBP-1c, and FAS in HFD-STZ induced diabetic rats.

Recent trends in extraction,identification and quantification methods of Centella asiatica phytochemicals with potential applications in food industry and therapeutic relevance:A review

Centella asiatica,a pre-historically utilized medicinal herb that is well recognized as a traditional phytotherapeutic substance for treating a variety of diseases.However,its phytochemicals use as a functional component in food and beverage has recently attracted the attentions of food researchers and scientists.C.asiatica possesses pharmacological value due to the presence of phytochemicals like flavonoids and terpenoids,mainly asiatic acid,asiaticoside,and madecassoside.Its role as a functional component in developing various processed food products and packaging films is continuously being explored.It improves the micronutrient profile and antioxidant potential of developed food products like noodles,chocolates,soups,pasta,etc.However,comprehensive scientific validation based on clinical trials is inadequate,which impede the perception of health benefits and nutritional importance of C.asiatica rich food products.Furthermore,there is a need to extensively examine the composition of C.asiatica active compounds in order to maximise its application in the food processing and preservation industry.Therefore,the goal of this paper is to investigate into the existing information on the extraction,identification,and quantification of C.asiatica phytochemicals,as well as to explore their biological activity.The potential of C.asiatica for developing functional foods and beverages,as well as their processing and preservation to improve human health,is also highlighted.

Gathering scientific evidence for a new bioactive natural ingredient:The combination between chemical profiles and biological activities of Flueggea virosa extracts

Flueggea virosa (Roxb. ex Willd.) Royle is a plant with several traditional uses in tropical countries. To study the potential usefulness, extracts from stem barks and leaves of F. virosa were obtained with different solvents. The phytochemical composition was assessed using LC-MS and NMR. Triterpenes, as oleanolic (0.05-88.09 mg/g extract), and ursolic (0.03-94.36 mg/g extract) acids were determined. In addition, ellagic and gallic acid derivatives were present in large concentrations in some of the extracts. Antioxidant (radical scavenging, reduction ability, and metal chelating) and enzyme inhibitory (cholinesterase, tyrosinase, amylase, and glucosidase) effects were assessed by in vitro chemical assays. The methanol extracts and infusions from both parts show higher antioxidant ability when compared with ethyl acetate extracts, and the antioxidant capacity was correlated with the total phenolic contents of the tested extracts. The extracts demonstrate enzyme inhibitory abilities on AChE and BChE, and multivariate approaches allowed for correlating the activities with the presence of triterpenoids (R > 0.8). Furthermore, molecular docking was used to get insights into the interactions between the triterpenoids and the tested enzymes. Together, these results indicate that F. virosa represents a significant source of naturally-occurring bioactive compounds that can be exploited as a new ingredient for the development of novel functional products with promising biological properties.