DETERMINATION OF QUALITY PARAMETERS, TOXICITY TEST, ANTIOXIDANT ACTIVITY, AND α-GLUCOSIDASE INHIBITORY ACTIVITY OF 70% ETHANOL EXTRACT BUNGUR LEAVES (LAGERSTROEMIA SPECIOSA L. PERS.)

Abstract

Objectives: The objective of this study is to investigate quality of extract, toxicity test, antioxidant activity, and test the α-glucosidase enzyme inhibitory effects of extract of bungur (Lagerstroemia speciosa L. Pers.) leaves.Methods: Extraction of leaves was conducted with maceration using 70% ethanol as solvent, followed by extract quality determination that involved extract-specific parameters. The toxicity test was performed by brine shrimp lethality test (BSLT) method, antioxidant activity by 1,1-diphenyl-2- picrylhydrazyl method, and the researchers used in vitro assay for α-glucosidase enzyme inhibitory effects.Results: Organoleptic result of the extract showed that the extract has a thick consistency, greenish-brown color, spicy taste and has not a specific aromatic odor. Phytochemical screening result indicates the presence of the simplicia ethanol extract from bungur leaves containing flavonoids, saponins, tannins, steroids, and triterpenoids. The water-soluble content 44.10%, ethanol-soluble content 60.00%, loss on drying 9.35%, water content 7.30%, total ash content 7.71%, acid-insoluble ash content 0.64%, water-soluble ash content 6.22%, ethanol residual content 0.24%, Pb and Cd metals contaminant 0.36 mg/kg and 0.10 mg/kg, microbial contamination of total plate number showed 4.32×102 colony/g, molds and yeasts number ≤1×103 colony/g, BSLT toxicity test with IC50 values of 109.4 μg/mL, antioxidant activity with IC50 values of 26.5 μg/mL and had α-glucosidase enzyme inhibitory effects, with IC50 values of 78.6 μg/mL.Conclusion: The standardized extract of bungur (L. speciosa L. Pers.) leaves are toxic, have antioxidant activity, and have α-glucosidase enzyme inhibitory activity.