Pungency and Bitterness

The thalli of Conocephalum conicum and Wiesnerella denudata contain a pungent substance. Pungency is due to a sesquiterpene lactone, tulipinolide 

Plagiochiline A (46) and plagiochiline I (54) display a very intense pungent taste 38,56,60,64,66a, 68, 71). The hot taste of these hemiacetals is somewhat different from that of polygodial (307) and (356, 362). The methoxylated plagiochilines Aj and A2 (98,99) show the same pungency as plagiochilines A and I 64). 

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