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United States Department of Agriculture

Agricultural Research Service

Title: Occurrence of (+) and (-)-Gossypol in Seed from Wild Species of Gossypium

Authors
item Stipanovic, Robert
item Puckhaber, Lorraine
item Percival Jr, Albert
item Bell, Alois

Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: January 7, 2005
Publication Date: February 15, 2005
Citation: Stipanovic, R.D., Puckhaber, L.S., Percival, Jr., A.E., Bell, A.A. 2005. Occurrence of (+)- and (-)-gossypol in seed from wild species of Gossypium [abstract]. In: Proceedings of the Beltwide Cotton Conferences, January 4-7, 2005, New Orleans, Louisiana. 2005 CDROM.

Technical Abstract: Glanded cottonseed contains a toxic compound called gossypol. This compound occurs in two enantiomeric forms that are designated as (+)- or (-)-gossypol. The biological activity of these enantiomers differs significantly. Notably, the (+)-enantiomer appears to have little, if any, detrimental effect on chickens when it is incorporated into their feed, while (-)-gossypol significantly reduces weight gain. Thus, it might be possible to utilize cottonseed that contains almost exclusively the (+)-enantiomer in feed for non-ruminant animals. Interestingly, the (-)-enantiomer shows anti-cancer activity, is active against HIV, and is an antiamoebic agent. The variations in the (+)- to (-)-gossypol ratio have been reported in Upland and Pima cottons. In most commercial U.S. Upland cottons (Gossypium hirsutum), the ratio of (+)- to (-)-gossypol is approximately 3:2. However, some cultivars of the marie-galante variety of G. hirsutum grown in Brazil (i.e., moco) have more than 97% (+)-gossypol. In Pima cottons (G. barbadense), this ratio may be reversed with a (+)- to (-)-gossypol ratio as low as 31:69. We now report the results of an investigation of the (+)- to (-)-gossypol ratios and concentration of gossypol in seed from wild species of Gossypium that are held in the U.S. Cotton Germplasm Collection in College Station, Texas. Previously, only G. barbadense cultivars were reported to produce an excess of (-)-gossypol. We now report that accessions of G. darwinii, G. sturtianum, G. harknessii, G. areysianum, G. longicalyx, and G. costulatum also produce an excess of this enantiomer. Of these, the G. longicalyx and G. darwinii accessions produce the highest ratios of (-)-gossypol in conjunction with a respectable amount of total gossypol [i.e., 62% (-)-gossypol (1.3% total gossypol) and 59% (-)-gossypol (2.3% total gossypol), respectively]. We also identified species with very high levels of (+)-gossypol {G. mustelinum [94% (+)-gossypol, (0.31% total gossypol)]; G. anomalum [98% (+)-gossypol (0.25% total gossypol)]; G. capitisviridii [96% (+)-gossypol (0.10% total gossypol)]; and G. gossypioides [94% (+)-gossypol (0.15% total gossypol)]}. Incorporation of the high (+)-gossypol trait into commercial cottons could provide a seed suitable as feed for non-ruminant animals. Alternatively, incorporation of the predominant (-)-gossypol trait into cottonseed could provide seed from which the biologically active (-)-enantiomer could be extracted and used for medicinal purposes.

Last Modified: 10/1/2014