ABSTRACT
Polyacetylenic compounds are a diverse group of secondary metabolites from terrestrial plants, most frequently from the family Compositae. These polyacetylenic compounds from the family Compositae and other higher plants are well documented (Bohlmann et al. 1973, 1988). As for the physiological roles of these acetylenes in the plants themselves, little is known though there are several indications that these compounds may be linked with special hormonal functions in plant metabolism. Observations have been made showing that the concentrations of special acetylenes vary drastically during the vegetation period. Some natural acetylenes showed powerful biological activity of various kinds, but only a very limited number of these compounds could be investigated since they were available only in small amounts. The acetylenes from higher plants often show antibiotic activity, though their toxicity and instability preclude any practical application of the compounds. When the safflower is infected by the pathogenic fungus Phytophthora drechsleri, the concentration of the highly antifungal compound, polyacetylene, increased twenty-fold. These observations throw some light on the role of polyacetylene as antifungals (Allen and Thomas 1971).
