Determination of Ellagic acid in Lagerstroemia speciosa L. Leaf Extract

Introduction Lagerstroemia speciosa L., known as Banaba (Family Lythraceae) is widely grown in Thailand and Southeast Asian countries.1 The plant is traditionally used as an herbal medicine for diabetics. Currently, ellagic acid, one of the major active compounds in Banaba leaves,2 has been reported to have a variety of biological activities such as antioxidant, anti-inflammatory and anti-arthritic properties.3-6 Interestingly, these properties suggested that ellagic acid could possibly be used for protection of arthritis. Bioactive compounds of Banaba leaves have been quantified by using nuclear magnetic resonance spectroscopy, high performance liquid chromatography (HPLC) and high performance thin layer chromatography.7-9 The complex mixture of compounds in Banaba leaf powdered extract are difficult to separate. Although there are several studies on chemical constituent of Banaba leaf, there is no report about the determination of ellagic acid in Banaba leaf powdered extract. The determination of ellagic acid content is important for quality control of Banaba leaf powdered extract and its related products. Hence, this study aimed to develop HPLC analytical method for quantification of ellagic acid in Banaba leaf powdered extract