Determination of ascorbic acid, total phenolic content and antioxidant acttvities in turmeric leaf / Faiza Ismail

Turmeric leaf is a common plant in Malay cooking as flavor enhancer. This study was conducted to determine the content of ascorbic acid and total phenolic; as well as to evaluate the antioxidant activity in the extract of the different maturity of turmeric leaf. TLA referred to less mature turmeric leaf, while TLB represented the more mature leaf; characterized by different size (length and diameter). Methanol was used as sol vent and all analysis were subjected to UV Spectrophotometer. Results indicated that TLB contain higher ascorbic acid (5.60mg/100g) compared to TLA (5.09mg/100g) on dry weight basis. Total phenolic content was measured using Folin-Ciocalteau assay and comparatively, TLB contain higher total phenolic content (77.36mg/100g) than TLA (55.22mg/l00g) and results were expressed as gallic acid equivalent (GAE). These values were significant different at p<0.05. Antioxidant activity was measured according to the [ï-carotene bleaching method. TLB exhibited higher AA% (81.7%) compared to TLA (13.8%). Positive correlations were found between total phenolic content in turmeric leaf extracts and the antioxidant activities.