Evaluation of in vitro antioxidant, antiglycation and antimicrobial potential of indigenous Myanmar medicinal plants.

Myanmar has a long history of using medicinal plants for treatment of various diseases. To the best of our knowledge there are no previous reports on antiglycation activities of medicinal plants from Myanmar. Therefore, this study was aimed to evaluate the antioxidant, antiglycation and antimicrobial properties of 20 ethanolic extracts from 17 medicinal plants indigenous to Myanmar.

In vitro scavenging assays of 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), superoxide (SO) radicals were used to determine the antioxidant activities. Folin-Ciocalteu's method was performed to determine the total phenolic content. Antiglycation and antimicrobial activities were detected by bovine serum albumin-fluorescent assay and agar well diffusion method.

Terminalia chebula Retz. (Fruit), containing the highest total phenolic content, showed high antioxidant activities with inhibition of 77.98% ± 0.92%, 88.95% ± 2.42%, 88.56% ± 1.87% and 70.74%± 2.57% for DPPH, NO, SO assays and antiglycation activity respectively. It also showed the antimicrobial activities against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans with inhibition zone of 19, 18, 17, 25 and 15 mm, respectively. Garcinia mangostana Linn. showed the strongest activities for SO and antiglycation assays with inhibition of 93.68% ± 2.63% and 82.37% ± 1.78%. Bark of Melia sp. was the best NO radical scavenger with inhibition rate of 89.39%± 0.60%.

The results suggest that these plants are potential sources of antioxidants with free radical-scavenging and antiglycation activities and could be useful for decreasing the oxidative stress and glycation end-product formation in glycation-related diseases.