Supinya Tewtrakul, Arunporn Itharat, Piboon Thammaratwasik, and Buncha Ooraikul

pp. 467 - 473

Abstract

Thirteen Thai crops including banana, okra, jackfruit, germinated rice, rambutan, durian, jampadah, huasa potato, tamarind, coconut, mango, fan palm fruit and dioscorea tuber were tested for anti-allergic effect using RBL-2H3 cells and anti-microbial activity. These 13 crops, some of which included different parts, e.g. skin, flesh, and seed, were extracted with
four solvents separately [(95% ethanol (EtOH), 50% EtOH, water (W) and hot water (HW)], respectively, to obtain 112 extracts. Among these extracts, mango seed in 50% EtOH possessed the highest anti-allergic activity against antigen-induced β-hexosaminidase release as a marker of degranulation in RBL-2H3 cells with an IC₅₀ value of 7.5±0.8 µg/ml, followed by banana (W, IC₅₀ = 13.5±2.4 µg/ml), okra (W, IC₅₀ = 13.6±3.1 µg/ml), jampadah skin (HW, IC₅₀ = 13.8±3.9 µg/ml), tamarind seed coat (HW, IC₅₀ = 14.2±3.1 µg/ml), jampadah flesh (W, IC₅₀ = 14.6±3.1 µg/ml); whereas other crops possessed IC₅₀ values from 21.5->100 µg/ml. Moreover, the plants showing high anti-allergic effects were also possessed marked antibacterial activity. Rambutan peel, mango peel, mango seed and tamarind seed coat exhibited appropriate anti-bacterial activity against Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa with MIC values ranging from 250-
2,000 µg/ml, but did not show any effect towards Escherichia coli and Candida albicans. This study indicates that these Thai crops may have potential as functional foods and neutraceuticals for treatment of allergy, allergy-related diseases and some bacterial infections.