Gossypol, in cottonseed

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. 

Gossypol is chemically reactive due to the reactivity of carbonyl and phenolic hydroxyl groups as well as its bulky binaphthalene structure. Gossypol can react with other compounds to form bound gossypol (BG). In order to better describe the chemical status (forms) of gossypol in cottonseed products, three terms (i.e., FG, BG, and TG) are frequently used. Based on the AOCS (American Oil Chemists Society) official... 

Methods for the quantitative determination of gossypol in cottonseed, oil, press-cake, and meal have been reviewed by Markman (1968). These methods include gravimetric, volumetric, colorimetric, spectrophotometric, polarographic, and luminescent means. 

Barraza, M. L., Coppock, C. E., Brooks, K. N., Wilks, D. L., Saunders, R. G., and Laimer, G. W., Jr. (1991). Nutrition, feeding, and calves-iron sulfate and feed pelleting to detoxify free gossypol in cottonseed diets for dairy cattle. Dairy Sci. 74, 3457-3467. 

Calhoun, M. C., Huston, J. E., Kuhlmann, S. W., Baldwin, B. C., Jr., Engdahl, B. S., and Bales, K. W. (1990b). Comparative toxicity of gossypol acetic acid and free gossypol in cottonseed meal and Pima cottonseed to lambs. In "Sheep and Goat, Wool and Mohair, Research Reports. PR 4779." Texas A M University System, College Station, TX. 

Wang, X. and Plhak, L. C. (2004). Monoclonal antibodies for the analysis of gossypol in cottonseed products.. Agric. Food Chem. 52, 709-712. 

Yannai, S. and Bensal, D. (1983). Gossypol in cottonseed products Toxicology and inactivation. Toxicology in the use, misuse and abuse of food, drugs and chemicals. Arch. Toxicol. Suppl. 6, 167-174. 

Most of the natural constituents of the edible oils produced in large quantity in the world, does not cause any hazard to human health. But there are exceptions, f.e., the gossypol in cottonseed oil. By processing, these components have to be removed. 

The concept of torsional asymmetry is not jnst an interesting abstract idea. Some years ago, fertility in some Chinese rnral commnnities was found to be below normal levels, and this was traced back to the presence of gossypol in dietary cottonseed oil. Gossypol acts as a male contraceptive, altering sperm matnration, spermatozoid motility, and inactivation of sperm enzymes necessary for fertilization. Extensive trials in China have shown the antifertility effect is reversible after stopping the treatment, and it has potential, therefore, as a contraceptive for men. 

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. 

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