Effect of Different Drying Methods on the Total Phenolic and Flavonoid Content and DPPH Free-Radical Scavenging Activity of Pandanus amaryllifolius Roxb. Planted in Mekong Delta

Aims: This study aimed to investigate the total phenolic and flavonoid content DPPH free-radical scavenging activity of Vernonia amygdalina planted in Mekong Delta. The optimized conditions for maceration pandan leaves included drying method, ratio leaf powder-to-solvent, extraction time.
 Methodology: fresh were divided into two equal portions, subjected different methods: shade oven drying. dried powder was macerated ethanol at room temperature. conducted with 3 ratios powder-to-solvent (w/v) (1:10, 1:15 1:20), time 1, 2 days. determined using aluminum chloride method whereas assessed Folin-Ciocalteu assay. Meanwhile, antioxidant plant extracts quantitatively evaluated test.
 Results: results indicated that best 1:10 shade-dried 1-day time. Accordingly, found be highest value 130.02 ± 2.24 mg QE/g extract 100.67 1.76 GAE/g (p < 0.05), respectively. lowest IC50 0.90 0.02 mg/mL 0.05). In addition, Pearson’s correlation coefficient between scavenge R2 = 0.74 compared 0.69, indicating capacity influenced chiefly by compounds.
 Conclusion: There a significant difference oven-dried extracts.