ANTIMICROBIAL, CYTOTOXIC, AND ENZYME INHIBITORY ACTIVITIES OF Garcinia mangostana L. PERICARP EXTRACT RELEVANT TO DIABETES AND ALZHEIMER’S DISEASE: FINDINGS FROM AN IN VITRO STUDY

Abstract

This study evaluated the antimicrobial activity, enzyme inhibition (of α-glucosidase and acetylcholinesterase), and in vitro cytotoxicity of the crude extract from mangosteen (Garcinia mangostana L.) pericarp. The antimicrobial activity was assessed against seven Gram-positive, Gram-negative bacterial, and yeast microbial strains. The half maximal inhibitory concentration (IC₅₀) values of α-glucosidase and acetylcholinesterase inhibition were determined using interpolation methods with TableCurve software. Cytotoxicity was evaluated on Vero and HEK293 cell lines. The extract exhibited selective antibacterial activity against Gram-positive bacteria (Staphylococcus aureus, Lactobacillus fermentum, and Bacillus subtilis) with minimum inhibitory concentration values ranging from 4 to 16 µg/mL and IC₅₀ < 10 µg/mL. In enzyme inhibition assays, the extract showed moderate inhibitory activity with IC₅₀ values of 99.37 µg/mL for α-glucosidase and 83.20 µg/mL for acetylcholinesterase, higher than reference drugs but still within a biologically active range. Cytotoxicity assays revealed IC₅₀ values of 64.97 µg/mL on Vero cells and 53.42 µg/mL on HEK293 cells. Overall, the mangosteen pericarp extract demonstrated notable biological activity and acceptable cellular safety, suggesting its potential as a natural therapeutic candidate for the supportive treatment of microbial infections, metabolic disorders, and neurodegenerative diseases. Further in-depth studies on molecular mechanisms and in vivo efficacy are required to validate its clinical applicability.