Influence of some defoliants on the gossypol pigments of cotton seeds

The influence of a number of defoliants on the gossypol pigments of cotton seeds of variety S-4880 has been studied. It was established that the qualitative compositions of the pigments of the defoliant-treated plants and of the control plants were identical. However, their quantitative composition in seeds treated with defoliants having a severe action had changed substantially: they contained larger amounts of the bound forms of gossypol than in the variants with defoliants having a mild action.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 208–212, March–April, 1993.     

Influence of wilt infection on the gossypol pigments of seeds and roots of a cotton plant of the variety Tashkent-1

A study has been made of the gossypol pigments of the seeds and roots of a cotton plant of the variety Tashkent-1 infected with wilt in comparison with a healthy plant. The amount of gossypol in the infected plant was lower than in the healthy plant. In the diseased plant, gossypurpurin was concentrated in the roots, and in the healthy plant it was concentrated in the seeds. Gossypol possessing optical activity was detected in the seeds and roots of both the healthy and the diseased plants.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 63–66, January–February, 1989.     

Enzymatic-chemical isolation of lipids, proteins, and gossypol from cotton seeds and meal. I

An enzymatic-chemical method of isolating the complex of lipids, gossypol pigments, and water-soluble proteins from cotton seeds and meal has been developed which permits: a) the achievement of the maximum yield of all types of lipids without their degradation; b) a rise in the qualitative and food value of the oil and protein products isolated from the seeds, with an increase in the solubility of the latter; c) the extraction from cotton seeds of more than 75% and from cottonseed meal of 42% of the free gossypol. The method, in combination with Folch's procedure, is suitable for the quantiative estimation of the lipids, strongly bound to the protein of the nucleus.Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodynykh Soedinenii, No. 5, pp. 621–628, September–October, 1991.     

Gossypol-like compounds of the cotton plant. Methods of determining gossypol

This review is devoted to the study of gossypol and gossypol-like pigments. It is reported that some of them are phytoalexins with respect to certain fungal pathogens of the cotton plant and possess a high toxicity. Methods of determining free and total gossypol in cottonseed processing products are discussed particularly.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 121–139, March–April, 1981.     

Lipids ofGossypium mexicanum

The surface lipids of the coat and the lipids of the kernel of the seeds of a wild form of the medium-fibered cotton plantGossypium mexicanum var.nervosum have been studied in comparison with cultured species. Using the methods of CC, TLC, and GLC, and UV and mass spectrometry, in the cuticular lipids ofG. mexicanum three classes of neutral lipids have been detected, and in the kernel lipids 10 classes of neutral lipids, 2 classes of glycolipids, and 7 classes of phospholipids. The structures of the epoxyacyl-, hydroxyacyl-, and diacylglycerols of the kernel have been established. The greatest differences between the seeds of the wild form of the cotton plant and the cultured species are the greater weight of the seed coat, the presence in it of a considerable amount of the 18:1 and of medium-molecular-weight fatty acids, and a higher level in the kernel of gossypol pigments, polar lipids, and acylglycerols containing the 18:2 acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 57–62, January–February, 1987.     

Influence of plant additives on properties of polymers

The chemical composition of the fatty mass representing a waste from the oils and fats industry has been studied. It has been shown that of the fatty acids the 18:2 species possesses a pronounced stabilizing action on polymers, and of polyolefins the least oxidized part of the gossypol pigments, while the fatty mass is a more effective stabilizer than its individual components.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 616–621, September–October, 1989.     

Cotton-plant protein isolates

The seeds of the cotton plant are an important source of food protein. The presence of gossypol in the seeds limits the use of protein isolates as additives to food products. The use of salt and alkaline solutions for extracting the proteins leads to the formation of isolates with relatively high gossypol constants. Extraction in an acid medium permits the presence of the toxin to be excluded. In this process, a number of problems arise which are connected with the presence of a large amount of phytin (about 5%) in the seeds of the cotton plant. The latter affects both the yield of food protein on extraction and functional properties. A method is proposed for eliminating traces of phytin from an acid isolate. A substantial influence of phytin on the properties of the proteins has been observed in those cases where the latter is strongly bound to the proteins at acid pH values.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 366–369, May–June, 1983.     

Enzymatic-chemical isolation of lipids,proteins, and gossypol from cotton seeds and meal. I

An enzymatic-chemical method of isolating the complex of lipids, gossypol pigments, and water-soluble proteins from cotton seeds and meal has been developed which permits: a) the achievement of the maximum yield of all types of lipids without their degradation; b) a rise in the qualitative and food value of the oil and protein products isolated from the seeds, with an increase in the solubility of the latter; c) the extraction from cotton seeds of more than 75% and from cottonseed meal of 42% of the free gossypol. The method, in combination with Folch's procedure, is suitable for the quantiative estimation of the lipids, strongly bound to the protein of the nucleus.     

Dadi spectra of gossypol hexamethyl ethers and mixtures of them

The DADI spectra of the M⁺ ions of hexamethyl ethers of three tautomeric forms of gossypol and of mixtures of them have been studied. A specific fragmentation pathway of M⁺ for each form has been shown. On the basis of the results obtained, the amounts of the hexamethyl ethers of each tautomeric form produced in the methylation of gossypol have been found.Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 38–42, January–February, 1980.     

Extraction of gossypol

The conditions for the extraction of gossypol from cottonseed flakes and from isolated gossypol glands have been investigated. It has been established that the amount of gossypol extracted by hexane is affected mainly by the degree of stirring, the moisture content, the material, and the temperature. By steeping the flakes first with concentrated miscella and then with hexane it is possible to extract about 60–65% of the gossypol. It has been shown that hexane and miscella extract practically no gossypol either from dry or from moistened gossypol glands, and only acetone extracts it almost completely.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 157–160, March–April, 1980.     

X-ray structural investigation of gossypol and its derivatives. XXVII. Structure of the condensation product of gossypol and (−)-α-phenyletiiylamine

The structure of the product of condensation of gossypol with (–)--phenylethylamine has been determined. It has been shown that a possible cause of the difficulty in separating racemic gossypol into optically active components is not a racemization of (–)--phenylethylamine on its condensation with gossypol but the high tendency of gossypol and its derivatives to form dimers.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 676–681, September–October, 1995. Original article submitted February 6, 1995.     

Extraction of cottonseed oil

Summary It has been shown that oil of the best quality is obtained on its selective extraction by hexane. Subsequent extraction from the meal of gossypol by 70–80% aqueous, and then dry, acetone permits meal to be obtained with a light cream color containing 0.02% of free gossypol. The omission of dry acetone leads to a darkening of the meal.It has been established that it is possible to achieve a reduction in the consumption of solvents on the direct extraction of cottonseed flake by using weak oil and gossypol miscellas.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 170–173, March–April, 1978.     

Lipid composition of the seeds of the cotton plant infected with wilt

The qualitative and quantitative set of lipid components of the seeds of healthy cotton plants of the variety Tashkent-1 and plants infected with verticillium wilt have been studied. It has been established that the compositions of the lipids of the two samples differ considerably. The greatest differences are observed in the amounts of total lipids, gossypol, and low-molecular-weight volatile acids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 319–325, May–June, 1980.     

Isolation of gossypol from hexane-acetone miscellas

Summary 1. The influence of the nature of the alkali on the degree of extraction of gossypol from hexane — acetone miscellas by solutions of NH₄OH, borax, sodium carbonate, and caustic soda has been studied. It has been established that the maximum extraction of gossypol is achieved by using 2% caustic soda solution.2. It is proposed to treat the aqueous layer formed in the decomposition of the sodium gossypolate with sodium chloride, which enables the yield of gossypol to be raised to 90%.3. It has been shown that the concentration of the miscella in order to eliminate acetone does not lower the yield of gossypol on its isolation from caustic soda solution.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 177–180, March–April, 1978.     

X-ray investigation of gossypol and its derivatives

The first four homologues of the carboxylic acid series and first two homologues of the monohydric alcohol series with gossypol give equimolar H-clathrates with the channel-type structure that are isostructural with gossypolacetic acid. Formic and acetic acids are capable of forming with gossypol a continuous series of solid substitution solutions. The desolvation of the unstable H-clathrates of carboxylic acids and monohydric alcohols form one and the same polymorph of gossypol. By x-ray structural analysis, the structures have been determined of two complexes of gossypol: an H-clathrate with methanol and a solid solution on the replacement of formic acid by acetic acid in a gossypol matrix.Institute of Bioorganic Chemistry, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 191–197, March–April, 1992.     

Identification and quantification of gossypol in cotton by using packed micro-tips columns in combination with HPLC

Self-packed micro-tip columns containing a C₁₈-bonded silica stationary phase, based on the same principles as solid-phase extraction methods, were used to obtain gossypol and related sesquiterpenoid aldehyde-enriched fractions. The enriched metabolite fractions were then analyzed by optimized high-performance liquid chromatography (HPLC) with a C₁₈ column (4.6 mm×25 cm) eluted with the binary mobile phase acetonitrile–0.1% aqueous TFA solution (80:20). This method has proven to be highly reproducible. The precision and accuracy, as %RSD and %RME values, were determined to be less than 15% for the method. The minimum detection limit of gossypol was determined to be 10 ng (absolute gossypol). Absolute recovery was greater than 94% with a standard deviation of ±3.68%. This is a simple, fast, and cost-effective method for isolation, identification, and quantification of gossypol and related secondary metabolites. Comparative analysis of gossypol content was performed on different parts of the cotton plant (seeds, stems and leaves) of two different cultivars of Gossypium hirsutum L. (Acala_1517–70 and OR₁₉). The results indicate that the OR₁₉ cv naturally contains higher gossypol levels than the Acala cv. It was also found that treatment of leaves with a Verticillium dahliae-derived elicitor induced production of deoxyhemigossypol rather than gossypol.     

Photodynamic effects in the components of cotton seeds

The formation of a stable radical cation and of an unstable peroxide form of gossypol in the light under aerobic conditions has been established on the basis of an analysis of the ESR spectra obtained. The formation of mono- and dianions of gossypol in its alkaline solutions has been shown.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenni, No. 3, pp. 354–360, May–June, 1987.     

Functional properties of “cotton protein.” III. Influence of gossypol and phytates on the solubility of gossypulin

The solubility of gossypulin and its derivatives under various conditions has been studied by turbidimetric titration. It was found that the low solubility of the protein under investigation in the neutral range of pH values at a low ionic strength may be due to the presence of phytin and gossypol. The minimum in the solubility of the gossypol-free protein shifted into the more alkaline region (pH 6.0–6.7) as compared with the initial gossypulin (with 0.6% of gossypol). The treatment of gossypulin with dilute solutions of phytin at pH 5.0 led to a shift in the pH of precipitation (pH 3.75), but in the presence of an excess of phytic acid the aggregation capacity of the protein increased and the pH of precipitation changed (pH 4.5–5.0). When Ca²⁺ ions were added, there was a shift of the solubility minimum into the alkaline pH range. In the presence of pectin, the pH of precipitation of all the samples studied shifted into a more acid pH range.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 359–364, May–June, 1986.     

Some features of cottonseed globulins in solutions

The main globulin of cotton seeds can exist in various molecular forms with different molecular weights. The existence of such forms is a consequence of features of the structure of the protein, although the possibility of the participation of pigments in it is not excluded. The dimensions and shape of the molecule have been determined by electron microscopy.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 770–773, November–December, 1981.     

Imines of gossypol ethers

Imines of methyl ethers of gossypol have been synthesized for the first time, their structures have been shown, and their immunomodulating activities have been determined. The quinoid form of existence of the imines of the dimethyl ether and the benzoid form of the imine of the mexamethyl ether of gossypol have been shown.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 358–363, May–June, 1991.