Capillary electrophoresis to quantitate gossypol enantiomers in cotton flower petals and seed.

Gossypol is a toxic compound that occurs as a mixture of enantiomers in cotton plant tissues including seed and flower petals. The (-)-enantiomer is more toxic to non-ruminant animals. Efforts to breed cottonseed with a low percentage of (-)-gossypol requires determination of the (+)- to (-)-gossypol ratio in seed and flower petals.

Malvone A, a phytoalexin found in Malva sylvestris (family Malvaceae).

The isolation and structure of a phytoalexin, malvone A (2-methyl-3-methoxy-5,6-dihydroxy-1,4-naphthoquinone) is reported. Malvone A formation is induced in Malva sylvestris L. by the plant pathogen Verticillium dahliae.