is a polyphenol derived from the cotton plant (genus Gossypium, family Malvaceae).
Gossypol is a polyphenolic aldehyde that permeates cells and acts as an inhibitor for
several dehydrogenase enzymes. It is a yellow pigment
Among other things, it has been tested as a male oral contraceptive in China. In addition to its contraceptive properties, gossypol has also long been known to possess anti-malarial properties
Other researchers are investigating the anti-cancer properties of gossypol
A 1929 investigation in Jiangxi showed correlation between low fertility in males and use of crude cottonseed oil for cooking. The compound causing the contraceptive effect was determined to be gossypol
In the mid-1990s, the Brazilian pharmaceutical company Hebron announced plans to market a low-dose gossypol pill called Nofertil, but the pill never came to market. Its release was indefinitely postponed due to unacceptably high rates of permanent infertility. Between five and twenty-five percent of the men remained azoospermic up to a year after stopping treatment. The longer the men had taken the drug and the higher their overall dosage, the more likely the men were to have lowered fertility or to become completely infertile. Researchers have suggested that gossypol might make a good non-invasive alternative to surgical vasectomy
In 1998, the World Health Organization's Research Group on Methods for the Regulation of Male Fertility recommended that research should be abandoned. In addition to the other side effects, the WHO researchers were concerned about gossypol's toxicity: the toxic dose in primates is less than 10 times the contraceptive dose. This report effectively ended further studies of gossypol as a temporary contraceptive, but research into using it as an alternative to vasectomy continues in Austria, Brazil, Chile, China, the Dominican Republic, and Nigeria]