Background: Age and drying method of purple sweet potato leaves (Ipomoea batatas (L.) Lamk) affect the components of plants’ secondary metabolites. The flavonoid content in the extract of purple sweet potato leaf  (Ipomoea batatas (L.) Lamk) Antin 3 variety in which simplicia dried through freeze drying method (-45 ⁰C for 48 hours) was proved to be 2.16 times higher compared to those using oven drying method (40 ⁰C 24 hours).

Aim: The aim of this research is to find out the effect of leaf age and drying method of (Ipomoea batatas (L.) Lamk) Antin 3 variety on the total phenolic content. The leaf age and the simplicia drying method which produced the highest total phenolic concentration then will be selected for the Antin 3 leaf extract antibacterial test sample. Methods: The young and the old part of the leaves (Ipomoea batatas (L.) Lamk) Antin 3 variety were each dried with two different methods, namely freeze drying at -45 ⁰C for 48 hours and aerated drying at 37 ⁰C room temperature for 120 hours. Antin 3 leaf extract was obtained through kinetic maseration with 70% ethanol as a solvent and 40⁰C rotavapour. The young and old leaves extract are then named Young Freeze Dried, Young Aerated, Old Freeze Dried, and Old Aerated (YFD; YA ; OFD; OA). Each of it was measured the total phenolic content with a UV-Vis spectro-photometer using gallic acid as a standard. Results: Based on the results of the study, it was found that the total phenolic content of YFD; YA ; OFD; OA in a row were 13.21± 0. 087 %; 10.85± 0.072 %; 5.96± 0.091 %; 7.03± 0.196 % (GAE). This result was significantly different (p ≤ 0.05) using two ways anova statistic. Conclusion: Based on these results, young leaf (Ipomoea batatas (L.) Lamk) Antin 3 variety has higher total phenolic content than the old leaf.  Freeze drying in young leaf is considerably better than aerated method to keep the total phenolic content.

Key words: Antin 3, leaf age, drying method, total phenolic