Gossypol

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. 

Glanded cottonseed kernels contain 1.1—1.3% gossypol (19) plus related pigments that affect nutritional properties and color of the oil and meal. Cottonseed also contains the cyclopropenoid acids, malvafic and stercuhc acids, which exist as glycerides and are concentrated in the seed axis (32). 

Raw defatted cottonseed flours contain 1.2—2.0% gossypol [303-45-7] (7) (19). When cottonseed is treated with moist heat, the S-amino group of lysine and gossypol forms a derivative that is biologically unavailable thereby inactivating gossypol but further lowering the effective content of lysine. 

Use of some oilseed proteins in foods is limited by flavor, color, and flatus effects. Raw soybeans, for example, taste grassy, beany, and bitter. Even after processing, residues of these flavors may limit the amounts of soybean proteins that can be added to a given food (87). The use of cottonseed and sunflower seed flours is restricted by the color imparted by gossypol and phenoHc acids, respectively. Flatus production by defatted soy flours has been attributed to raffinose and stachyose, which are removed by processing the flours into concentrates and isolates (88). 

Other compounds that have shown promising properties in vitro against E. histolytica are niridazole (10), tinidazole (11, Fasigyn, Simplotan), gossypol (12), bithionol [(13), 2,2 -thiobis(4,6-dichlorophenol)], and pimaricin (14, Natamycia [7681-93-8]). The chemotherapy of amebiasis has been reviewed (9). 

Gossypol Pesticide/ anti- fe rtiB ty Low/bigb Cotton... 

The functional groups of abscisin II could easily arise from a precursor like violaxanthin (M), a carotenoid of widespread occurrence (see 11). Whatever the genesis of abscisin II, it is clear that it must be different from that of the bis-sesquiterpenoid, gossypol (N), which also occurs in the cotton plant and has received considerable attention. 

Adlakha RC, Ashom CL, Chan D, Zwelling LA. Modulation of 4 -(9-acridinyl-amino)methanesulfon m anisidide induced, topoisomerase ILmediated DNA cleavage by gossypol. Cancer Res 1989 49 2052-2058. 

For Schiff base being a derivative of gossypol and R-( I )-2-amino-3-benzyloxy-1-propanol, the conditions of the atropisomerisation were determined on the basis of the NMR spectra.37 The ratio of the diastereomers was established on the basis of the integrals of selected H signals (H-l and H-ll). The atropisomerisation of the gossypol Schiff base took place even if the samples were not exposed to the sunlight, however, this process was slower in the dark. The diastereopure Schiff bases were converted into a racemic mixture after ca. 12-14 h in the dark and ca. 3-3.5 h after irradiation of monochromatic light. The addition of a drop of water to acetonitrile solution accelerated the atropisomerisation. In this case, the 1 1 ratio of diastereomers was achieved after 45 min. The results obtained indicated that the atropisomerisation process cannot be considered as a simple photo-atropisomerisation. 

The presence of the photoepimerization of the Schiff bases being derivatives of gossypol and L-amino acid methyl esters was also observed... 

The values of 3/(NH,H) coupling constant observed for imine proton can be helpful in detection of the proton transfer processes and determination of mole fractions of tautomers in equilibrium. For NH-form, this value is close to 13 Hz, lower values usually indicate the presence of tautomeric equilibrium. It should be mentioned that the values below 2.4 Hz have not been reported. The chemical shift of C—OH (C-2 for imines, derivatives of aromatic ortho-hydroxyaldehydes or C-7 for gossypol derivatives) carbon to some extent can be informative, however, this value depends on type of substituents and should be interpreted with caution. 

The 15N chemical shifts measured for the Schiff base being a derivative of gossypol [7] and L-phenylalanine methyl ester equal —243.7 ppm in CDC13 solution and —237.5 in solid state (relative to external... 

T. Deuterium isotope effects on 13 C chemical shifts In the studies of proton transfer equilibrium of Schiff bases, the most informative are deuterium isotope effects measured for carbons bonded with proton donor groups (C-2 or C-7 for gossypol derivatives). For imines in which... 

Hansen et al.52 measured the deuterium isotope effects for the Schiff base being a derivative of racemic gossypol [7]. The high negative value of deuterium isotope effect observed at carbon C-7 linked with proton donor group (—190 — 240 ppb), solvent and temperature independent, clearly indicated the existence of this compound as enamine-enamine tautomer. 

The Food and Drug Administration approved the use of cottonseed containing not more than 450 ppm gossypol for human use. Glandless whole kernel cottonseed flakes and cot-n-nuts are commercially available. 

Studies incorporating cottonseed into many different foods have yielded acceptable products with improved protein quantity and quality. The presence of free gossypol and cyclopropenoid fatty acids (CPFA) potentially limits the use of cottonseed in human foods. 

The levels of free gossypol and CPFA are reduced in processing the seed and preparation of food. The amount of free gossypol and CPFA in the food as eaten should be determined. The American Oil Chemists ... 

Glanded cottonseed has been used to produce a defatted cottonseed flour with reduced gossypol content by a procedure known as the liquid cyclone process (LCP). LCP cottonseed flour has been used in the preparation of many foods that have been tested in several animal and human nutrition studies. The commercial production of LCP cottonseed flour has not been successful (5). 

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