Bound gossypol

One of the aldehyde groups of the gossypol is believed to react with the primary amine of the lysine units of the cottonseed proteins to form the Schiff base or imine type compound as shown at the top of Figure 12 (16, 17). An analytical method for determination of bound gossypol, developed by Pons et al. 

Figure 12. Reaction of protein-bound gossypol with 3-amino-l-propanol in the presence of acetic acid in DMF solution (4)...

This aminopropanol treatment for removal of bound gossypol appeared to be an excellent means to test the role of bound gossypol in the color problem. The water and salt-solution insoluble fraction (l) of LCP flour that contained the brown color causing pigments was treated for 15 min at 80°C with 2Z... 

The seven major flavonoids in these flours were isolated and identified as 3-0-glycosides of kaempferol and quercetin. The marked brown discoloration observed when LCP glanded cottonseed flour is used in a food product is caused by bound gossypol and at least two bound gossypol-like pigments. The brown color observed when glandless cottonseed flour is used in food is believed to be due to other phenolic constituents that are either insoluble polymers or are bound to the insoluble plant polysaccharides. 

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... 

ESSENTIAL AMINO-ACIDS OF COTTONSEED FUNCTIONAL PROTEIN ISOLATES AS AFFECTED BY THE PRESENCE OF BOUND GOSSYPOL (G) ... 

Figure 9.30 Reactions of gossypol (H2N-P = protein with bound lysine, H2N-L = phospholipid with bound ethanolamlne).

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