COMPARISON OF EXTRACTION METHODS ON ANTIOXIDANT ACTIVITY, PHENOLIC AND FLAVONOID CONTENT IN 96% ETHANOL EXTRACTS OF LANGSAT LEAVES (Lansium domesticum Corr.)

The leaves of Lansium domesticum Corr., commonly known as langsat, are recognized for their antioxidant properties attributed to the existence of phenolic and flavonoid components. Variations in extraction methods can affect the levels of these compounds, thereby influencing their antioxidant activity. The objective of this study is to compare the antioxidant activity, phenolic and flavonoid content of 96% ethanol extracts of langsat leaves obtained through four different extraction techniques. Langsat leaves powder was extracted using maceration, percolation, reflux, and soxhlet, and methods with 96% ethanol as the solvent, resulting in ethanol-based extracts. Antioxidant activity was analyzed using the ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)) assay with trolox as a standard. The phenolic and flavonoid contents were measured spectrophotometrically using Folin-Ciocalteu and AlCl3 reagents, with gallic acid and quercetin as standards, respectively. Data on antioxidant activity, phenolic and flavonoid levels from the four extraction methods were statistically analyzed to evaluate differences among the techniques. The percolation method yielded the highest antioxidant activity, with an IC50 value of 89.48 ± 0.17 ppm. Furthermore, this approach yielded the greatest amounts of phenolic and flavonoid compounds, with values of 138.69 ± 0.456 mg GAE/g extract and 5.38 ± 0.576 mg QE/g extract, respectively. Thus, percolation emerged as the most effective extraction method for maximizing antioxidant activity, phenolic and flavonoid content compared to maceration, reflux, and soxhlet methods.