Gossypol toxicity

In the next step, fatty acids are separated from the oil by neutralisation (deacidification or afkahne refining) with sodium hydroxide solution (which is also effective in the removal of toxic gossypol from cottonseed oil see Section 9.11). The free fatty acid content varies widely within 0.5-1.5% in seed oils from raw materials grown in a temperate zone. After neutrahsation, the fatty acid content falls below 0.1%. The resulting soaps are separated as soap stock and typically used in animal feed. Tropical oils, such as palm and coconut oils, contain 3-7% free fatty acids. It is therefore preferable to separate the free fatty acids together with volatiles by distillation in the end stage of physical refining process. In this case, the main components of the distillate are free fatty acids. 

SunUkumar G, Campbell LM, Puckhaber L, Stipanovic RD, Rathore KS. 2006. Engineering Cottonseed for Use in Human Nutrition by Tissue-Specific Reduction of Toxic Gossypol. Proceedings of the National Academy of Sciences USA 103 (48) 18054-18059. 

Since feeds contain other substances than those required by the animals of interest, studies have also been conducted on antinutritional factors in feedstuffs and on the use of additives. Certain feed ingredients contain chemicals that retard growth or may actually be toxic. Examples are gossypol in cottonseed meal and trypsin inhibitor in soybean meal. Restriction on the amount of the feedstuffs used is one way to avoid problems. In some cases, as is tme of trypsin inhibitor, proper processing can destroy the antinutritional factor. In this case, heating of soybean meal is effective. 

The importance of pigment glands as sources of toxins in cottonseed was suspected early in the twentieth century. In 1915 Withers and Carruth ( showed that the toxicity of cottonseed to animals was due to the compound gossypol localized in pigment glands. 

Only a few efforts have been made to evaluate the effects of TA structural variations on toxicity. Methylation decreases toxicity of hemigossypol to Verticillium dahliae (25), of gossypol to rat mast cells (23), and of various TA to HelionTis sod. (22). In contrast, methylaTTon increases the toxicity of various TA"To nematodes (26) and the toxicity of heliocides to rat mast cells ( ). The order of toxicity of different TA to rat mast cells is quinones > heliocides > naphthols > binaphthols (23). Gossypol generally is somewhat more toxic to insects than heliocides, and quinones are least toxic (29,22). 

Alkaloids are active bioagents in animal tissues. There is clear scientific evidence of this. Crawford and Kocan" " have tested the toxicity of steroidal alkaloids from the potato Solanum tuberosum), such as a-chaconine, a-solanine, solanidine and solasodine, and Veratrum alkaloid, jervine on fish. The results of Crawford and Kocan s research proved that rainbow trout exhibited a toxic response to chaconine, solasidine and solanine, while medaka only did so to chaconine and solanine. Embryo mortality was observed as an effect of toxicity in both species. Many other alkaloids are known to disturb or cause disorder in animal reproductive systems. For example, gossypol from cotton-seed oil is known as a clear reducer of spermatogenesis and premature abortion of the embryo. 

The toxicity of the cotton terpenoid aldehydes to different larvae has been reported by several groups (227, 259, 270-275). These results are summarized in Table 2. Although there is variation in the test results among the different laboratories, it is obvious that gossypol and probably the other terpenoid aldehydes have a wide range of toxicity to many moth larvae. 

N.A. Gossypol, flavonoids." This herb is toxic. As a labor-inducing agent, promote abortion or onset of menstruation. Gossypol causes infertility in men. 

Gossypol, toxic, dimeric sesquiterpene from cottonseed... 

Some inhibitory activity of gossypol against mouse mammary adenocarcinoma 755 and borderline activity against leukaemia P388 were reported [323, 324], The effective dose range of gossypol is rather narrow because of toxicity [324]. Gossypol has recently been found to be a specific inhibitor of DNA polymerase a [325], a major enzyme involved in DNA replication. This compound may also interfere with the DNA repair process [325]. 

Henry, M.H., Pesti, G.M. and Brown, T.P. (2001) Pathology and histopathology of gossypol toxicity in broiler chicks. Avian Diseases 45,598-604. 

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