Ripened tamarind pods of the sour tamarind, Tamarindus indica “Priao-Yak”, were collected from Phetchabun, Thailand. Herbarium specimens were deposited at the Museum of Natural Medicine, Faculty of Pharmaceutical Sciences, Chulalongkorn University. The tamarind seeds were separated and roasted in a pre-acid washed sand-bath at 150 °C for 1 h. The seeds were then quickly washed and dried in a hot air oven at 50 °C for 24 h. The seed coats were removed from the kernels, pulverized into a tamarind seed coat powder (TSCP). TSCP was extracted as previously described[18], with slightly modified. Three grams of TSCP was put in a cloth sack, dipped while shaking in 200 mL