BIO203H5 Lecture Notes - Lecture 8: Terpene, Isoprene, Allelopathy
Document Summary
Defenses: plants are immobile but not helpless, constitutive= there all the time, first line of defense against pathogens= waxy cuticle & cell walls (constitutive, chemical defenses against large herbivores often at least partly constitutive. Inducible= attacker is detected & a defense response is mounted. Includes anticancer drugs such as taxol (part terpene, part flavonoid: plant phenolics contribute to fragrances & flavours (eg. vanillin & capsaicin) Future of plant secondary metabolites: food crops bred for edibility & yield, efforts to breed back in some beneficial traits. Human health: >40% of naturally occurring secondary metabolites so far tested can/may cause cancer in animals, some others may help prevent cancer (eg. lycopene, natural does not equal healthy, herbal remedies may have serious side effects, eg. Echinacea carries elevated risk of spontaneous abortion: st. john"s wort & cardiac medication- willow accumulates heavy metals, non-pure active ingredients, dose= unpredictable, 2/3 of current drugs have plant origin (new drugs continue to be identified in plants)
