Antidiabetic potential of methanol extracts from leaves of Piper umbellatum L. and Persea americana Mill.

Objective: To determine inhibitory activity of methanolic leaf extract of Piper umbellatum and Persea americana(P. americana)(traditionally used in Cameroon against diabetes) on β-glucosidase, β-glucosidase, maltase-glucoamylase, aldose reductase and aldehyde reductase activities, enzymes involved in starch digestion or diabetic complications. Methods: The methanol extracts from Piper umbellatum and P. americana were prepared by maceration. To assess relative efficacy of these extracts, the determination of concentrations that were needed to inhibit 50% of enzyme activity was done, whereas, gas chromatography-mass spectrum was used to identify components from extracts that may be responsible for the activities. Results:The tested extracts strongly inhibited β-glucosidase, maltase-glucoamylase, aldose reductase and aldehyde reductase activities with IC50 ranging from(1.07 ± 0.03) to(31.77 ± 1.17) μg/mL.Among the tested extracts, P. americana was the most active against sensitive enzymes(IC50 of1.07 ± 0.03 to 15.63 ± 1.23). But, none of the extracts showed interesting inhibitory effect against β-glucosidase as their percentage inhibitions were less than 16%. From gas chromatographymass spectrum analysis, 10 and 8 compounds were identified in Piper umbellatum and P.americana extracts respectively, using NIST library 2014. Conclusions: Results of this study provide the scientific credential for a prospective usage of these plants to treat diabetes.

秦岭山脉杀虫植物的研究(英文)

通过筛选分离 ,获得了腺毛翠雀花 (Delphimium grandiflorum var.glandulosum)、大伞花楼梯草 (Elatostema umbellatum BL .var.majus Maxim)、毛莨 (Ranunculus japonica Thunb)、兔儿伞 (Syneilesisaconitif olia (Bge.) Maxim)等天然植物的提取液。以蟋蟀、蚱蜢、粘虫、毛虫为试虫 ,测定了各种提取液对试虫的毒杀活性 ,发现这几种植物均具有良好的杀虫活性。其中腺毛翠雀花、大伞花楼梯草在 30 min内对蟋蟀、蚱蜢 (体长≤ 3cm)杀死率达 90 %以上 。