Investigation of extraction conditions and evaluation of the ability of antioxidants and lowering blood glucose levels of the Ensete glaucum extract

Diabetes is a type of metabolic disorder, which is the cause of many dangerous complications. Ensete glaucum (Musaceae family) has active ingredients with antioxidant and hypoglycemic characteristics in some parts of the plant. This study investigates the ability to reduce blood sugar based on the inhibition of α-amylase and α-glucosidase enzymes of Ensete glaucum stem extract. The results indicated that 70% ethanol, a material ratio of 1/30, and a temperature of 65oC for 360 minutes are the optimal conditions for the extraction process. Sonication has an extraction efficiency that is 1.8 times greater than that of a thermostatic bath or shaker. With the above conditions, the total polyphenol contents of the upper and the lower stem samples combined with sonication are higher than those without sonication. The ability to capture 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals of the extract used with sonication in the upper stem is four times higher than without sonication. In addition, the presence of sonication increases the capacity to inhibit the α-amylase enzyme (IC50 of the upper stem is 29.94 g/mL, the lower stem is 16.42 g/mL), compared to the absence of sonication (IC50 of the upper stem is 36 g/mL, the lower stem is 26.72 g/mL). Similar to the ability to inhibit α-glucosidase enzyme when using sonication (IC50 of the upper stem is 71.04 µg/mL, the lower stem is 91.91 µg/mL) is higher than not using sonication (IC50 of the upper stem is 142.99 µg/mL, the lower stem is 129.88 µg/mL). In general, the inhibition of α-amylase enzyme was higher than α–glucosidase enzyme in all extracts. In addition, the presence of sonication increased the polyphenol content, DPPH free radical scavenging, and hypoglycemic capacity of Ensete glaucum stem extract.