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The objective of this study was to determine the effect of drying temperatures and times on total phenolic, flavonoid contents and their activities of Centella asiatica (L.) Urb leaves. The experiment was conducted as a 3 x 3 factorial in completely randomized design (CRD) with three replications. Two factors included three drying temperatures: 60, 70 and 80 ºC, and three drying times: 8, 10 and 12 hours. The results indicated that high drying temperature and time caused a decrease in the total phenolic content, total flavonoid content, and DPPH• radical scavenging activity. The highest total phenolic content was observed when samples were dried at temperature 60 ºC for 8 and 10 hours. Moreover, dried leaves at this temperature for 10 hours also contained the highest total flavonoid content and DPPH• free radical inhibition. Drying temperatures at 60 and 70 ºC for 10 hours resulted in the greatest ABTS+• radical scavenging activity. Therefore, the optimum drying temperature and time for C. asiatica (L.) Urb. leaves were 60 ºC for 10 hours.
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