EFFECT OF TEA EXTRACTS, CATECHIN AND CAFF EINE AGAINST TYPE-I ALLERGIC REACTION

The antiallergic effects of green tea, oolong tea, and black tea extra cts by hot water were examined. These extracts inhibited the passive c utaneous anaphylaxis (PCA) reaction of rat after oral administration. Three tea catechins, (-)-epigallocatechin (EGG), (-)-epicatechin galla te (ECg), and (-)-epigallocatechin gallate (EGCg) isolated from green tea showed stronger inhibitory effects than that of a green tea extrac t on the PCA reaction. The inhibitory effects of EGC and EGCg on the P CA reaction were greater than that of ECg. Caffeine also showed a inhi bitory effect on the PCA reaction. These results indicate that tea cou ld provide a significant protection against the type-I allergic reacti on. These findings also suggest that tea catechins and caffeine play a n important role in having an inhibitory effect on the type-I allergic reaction.