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1.
棉籽饼粕在饲料中的应用 总被引:2,自引:0,他引:2
本文评述了开发棉籽饼粕对发展我国养殖业的作用;目前影响我国棉籽饼粕作饲料的一些原因;现行制油工艺生产的棉籽饼粕在饲料中的应用;我国研究的工厂化生产去毒棉籽饼粕的一些不同工艺等问题。 相似文献
2.
从双液相溶剂棉仁浸取液中提纯棉酚 总被引:4,自引:0,他引:4
采用石油醚和甲醇的双液相溶剂浸取棉仁可以得到高质量的棉籽油和棉籽粕,棉仁中的棉酚大部分被甲醇溶解。从甲醇相中提取棉酚,可增加该工艺的的经济效益。考察了棉酚在甲醇相中的储存稳定性,储存温度越低,环境光线越弱,储存时间越短,棉酚损失越小。用水稀释法提取甲醇相中的棉酚,并对提取工艺进行了优化研究。较佳提取参数为:甲醇相溶剂浓缩至1.0 mL/g棉仁,向甲醇相浓缩液中加入2倍体积的水,分2次加入,破乳剂氯化钠加量1%(W/V浓缩液),调pH为5,静置8 h后分离沉淀。在此工艺条件下得到的棉酚产率为68.25%,纯度为96.89%。说明水稀释法是一种可行的从甲醇相中提取棉酚的方法。 相似文献
3.
The effects of varying gossypol intake from whole cottonseed and cottonseed meal on lactation and blood parameters in lactating dairy cows 总被引:1,自引:0,他引:1
Effects of varying amounts of gossypol from whole Upland cottonseed (WCS) and cottonseed meal (CSM) were evaluated in 40 midlactation Holstein cows. After 14 d of pretreatment, cows were assigned to 1 of the 5 treatments for 84 d: control (no gossypol), 931 mg/kg total gossypol (TG) and 850 mg/kg free gossypol (FG) from WCS (moderate TG and high FG); 924 mg/kg TG and 91 mg/kg FG from CSM (moderate TG and low FG), 945 mg/kg TG and 479 mg/kg FG with equal amounts of TG from WCS and CSM (moderate TG and FG), or 1894 mg/kg TG and 960 mg/kg FG with equal amounts of TG from WCS and CSM (high TG and FG). Concentrations of plasma gossypol (PG) and its isomers were directly proportional to FG intake. Concentrations of PG reached a plateau after 28 d on treatment, and they were highest in cows receiving a diet with high TG and FG. Erythrocyte fragility differed among treatments and increased with increasing FG intake. Plasma gossypol returned to negligible concentrations 28 d after withdrawal of cottonseed products from the high TG and FG diet. Serum vitamin A was similar among treatments, but vitamin E increased with increasing FG intake. Serum enzymes were generally unaffected by treatments, but urea N increased in diets higher in TG and FG. Intake of dry matter was higher for the diet high in TG and FG than for the control diet, but was similar for other treatments. Cows receiving the high TG and FG diet produced more milk and 3.5% fat-corrected milk, with no changes in milk composition. Feeding a diet containing 1894 mg/kg TG and 960 mg/kg FG for 84 d increased PG concentrations and erythrocyte fragility and resulted in minor changes in blood metabolites and enzymes, but no detrimental effect on lactation performance was observed. Indicators of liver, kidney, and muscle cell viability suggest that the higher amounts of gossypol consumed in this study had only minor effects on those tissues in lactating dairy cows. 相似文献
4.
5.
Induction of systemic resistance to feeding of beet armyworm, Spodoptera exigua, was investigated in two isogenic lines of Stoneville 213 cotton, Gossypium hirsutum, that differed in the presence of pigment glands. In laboratory bioassays, larvae strongly preferred to feed on glandless cotton plants when presented a choice between undamaged terminal leaves of undamaged glanded and glandless plants. Feeding damage inflicted by S. exigua larvae on the two oldest leaves of glanded plants seven days prior to feeding bioassays caused larvae to prefer by 33-fold the undamaged terminal foliage from undamaged plants compared to that from damaged plants. Feeding damage on glandless plants caused only a 2.6-fold greater preference for terminal foliage from undamaged plants over foliage from previously damaged plants. Extracts of terminal foliage from glanded cotton damaged seven days earlier had significantly greater quantities of terpenoid aldehydes (hemigossypolone, gossypol, and heliocides) than did foliage from undamaged glanded plants. Terpenoid aldehydes were undetectable in extracts of both undamaged and previously damaged glandless plants. The profile of volatile compounds collected from the headspace of mechanically damaged terminal leaves of undamaged glanded and glandless plants differed. Both cotton isolines released large quantities of lipoxygenase products (hexenyl alcohols, acetates, and butyrates), but glandless plants released only small amounts of mono- and sesquiterpenes compared to glanded plants. Glandless plants damaged seven days prior to volatile collection released significantly greater quantities of lipoxygenase products, -ocimene, and - and -farnesene than did undamaged glandless plants. Previously damaged glanded plants released significantly greater quantities of all mono- and sesquiterpenes and hexenyl acetates and butyrates, but not alcohols. The relative importance of volatile compounds versus terpenoid aldehydes in induced feeding deterrence in cotton to S. exigua larvae is still unclear. 相似文献
6.
Ethanol vapor deactivation of gossypol in cottonseed meal 总被引:3,自引:0,他引:3
R. J. Hron Sr. P. J. Wan M. S. Kuk 《Journal of the American Oil Chemists' Society》1996,73(10):1337-1339
Most cottonseed cultivars contain gossypol, a polyphenolic antinutritional compound. “Free” gossypol is a physiologically
active form of gossypol, which is toxic to young- and nonruminant animals. To utilize solvent-extracted cottonseed meal as
a general feed, gossypol must be either removed or deactivated to a minimum level specified for each class of animal. Normally,
deactivation is carried out prior to oil extraction; however, the desired level of deactivation is not always attained. A
new supplemental method of deactivation has been found by using either ethanol or isopropanol vapors on solventextracted meal.
In a bench-top set-up, ethanol vapor reduced free gossypol from 0.115 to 0.053%, and a further reduction to 0.026% has been
observed with the addition of ferrous sulfate. The supplemental deactivation method can, in most cases, reduce free gossypol
to significantly safer levels for feeding, thus increasing utility, and possibly demand, for cottonseed meal as a general
animal feed protein source.
Presented in part at the AOCS Annual Meeting, Atlanta, GA, May 8–12, 1994. 相似文献
7.
An improved ultrasound‐assisted extraction process of gossypol acetic acid from cottonseed soapstock
Guangfeng Jia Yonghua Zhan Daocheng Wu Yang Meng Liang Xu 《American Institute of Chemical Engineers》2009,55(3):797-806
To investigate the extracted process of gossypol acetic acid (G‐AA) from cottonseed soapstock and explore the improvement of its yield and purity, a novel ultrasound‐assisted extraction and crystallization method was introduced to this process. Under the optimized conditions, preliminary G‐AA with the yield of 1300 mg and the purity of 95.9% could be obtained from 100 g of fresh soapstock by ultrasound‐assisted extraction. In addition, UV, IR, and NMR spectrum further confirmed the detailed chemical structure of G‐AA. Assay of inhibiting human prostate tumor cell line PC‐3 and human breast cancer cell line MDA‐MB‐231 revealed its biological activity, the values of IC50 are 9.096 μmol/L and 14.37 μmol/L respectively. In comparison with the conventional solvent extraction, this novel process increases the content of G‐AA over 90%, reduces the time of crystallization by 75%, and retains the anticancer activity of gossypol. © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
8.
Villaseñor M Coscioni AC Galvão KN Chebel RC Santos JE 《Journal of dairy science》2008,91(8):3015-3024
Our objectives were to determine the effects of dietary free gossypol (FG) intake on plasma and uterine gossypol concentrations and embryo development and viability before and after culture with gossypol. Fifty postpubertal Holstein heifers weighing (±SD) 406 ± 34.5 kg at 11.5 mo of age were blocked by age and body weight (BW) and randomly assigned to 1 of 3 isocaloric and isonitrogenous diets differing in their FG content: control (0 mg of FG/kg of BW), moderate (17.8 mg of FG/kg of BW), and high (36.8 mg of FG/kg of BW). Heifers were fed the diets for 70 d before superovulation and embryo collection. Superovulated heifers were flushed on d 5 after induction of ovulation, and early morulae were either stained, to determine the number and proportion of live and dead cells, or randomly assigned to an in vitro culture for 96 h in media containing either 0 or 10 μg/mL of gossypol acetic acid. Plasma and uterine gossypol concentrations increased with increasing gossypol intake. The number of low-quality embryos-ova was greater for the high than for the moderate and control diets. Embryos collected from the high diet had the least number of cells because of fewer live cells, and were smaller in diameter. Greater dietary gossypol reduced blastocyst development and extended the time to reach the blastocyst stage. Similarly, gossypol concentration at 10 μg/mL compromised in vitro development and increased the proportion of degenerated embryos at 96 h in culture. These findings provide in vivo and in vitro evidence that intake of 36.8 mg of FG/kg of BW per d and gossypol concentrations >7 μg/mL in plasma, in uterine flush, or in vitro compromise early embryo development, which might explain some of the negative effects of gossypol on the fertility of dairy cows. 相似文献
9.
棉酚是一种多酚类化合物,由于它在男性避孕方面有副作用,WHO已禁止其作为人类抗生育药物。近年随着抗肿瘤生物活性的深入研究,它可能成为新的抗肿瘤药物。现从抗增殖,干预信号传导通路,干预能量代谢以及抑制Bcl-2蛋白表达4个方面阐述棉酚的抗肿瘤作用机制,并介绍了国内从棉仁、棉籽毛油和油脚及皂脚等多途径回收棉酚的新方法。 相似文献
10.
棉仁蛋白是一种潜在的重要食品资源,由于棉酚的存在一直未被人类充分利用。通过甲醇脱酚、4#溶剂脱脂、低温连续脱溶的棉籽粕生产工艺和碱溶酸沉的蛋白生产工艺,于2001年首次实现了工业化利用有腺体棉籽粕生产食用棉仁分离蛋白的实践,获得了高安全性的棉仁分离蛋白。 相似文献