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11.
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   
12.
Flavonoids and saponins from common beans have been widely studied due to their bioactivity. This research evaluated the effect of germination of black beans (Phaseolus vulgaris L.) on the antioxidant capacity and antiproliferative activity against cancer cell lines of saponins and flavonoids extracted from seed coats, cotyledons and sprouts. Principal component analysis was performed to achieve punctual associations between the black bean saponins and flavonoids concentrations to the antioxidant capacity and the antiproliferative activities. Total phenolic content and antioxidant capacity of extracts were higher when obtained from seed coats, mainly from the 3rd germination day. The extracts obtained from seed coats after 3 and 5 germination days inhibited all cancer cell lines proliferation with no cytotoxicity against control cells. Genistein was related with the activity against mammary cancer cells but flavonols and group B saponins were more related with hepatic and colon cancers. Non-glycosilated flavonols were related with antioxidant capacity.  相似文献   
13.
玉米胚的营养成分及其控制体重、预防心肌病变作用研究   总被引:10,自引:0,他引:10  
目的:研究玉米胚的营养成分以及对大、小鼠体重、存活率及心脏病变等生长状况的影响。方法:对玉米胚的营养素、微量元素、氨基酸组成进行了分析;用高脂饲料造成鼠类衰老模型,实验组在高脂饲料中加入10%或15%的玉米胚,以Wistar雄性大鼠和瑞士雄性小鼠的长期或终生喂养,观察对比各组鼠类的体重及月别存活率和平均存活率,并对死亡大鼠作病理检查,统计心肌病变率。结果:玉米胚中蛋白质、脂肪、碳水化合物、灰份、水分及膳食纤维含量(%)分别为15.2、11.7、52.5、7.0、1.6和12.0,而且含有丰富的维生素与微量元素,其亚油酸与必需氨基酸含量也很高。实验组与高脂模型组比较,大、小鼠体重与心肌病变率极其显著降低(p<0.01),平均存活率明显升高(p<0.01或p<0.05)。结论:玉米胚具有很高的营养价值,可以控制动物体重,预防心肌病变,提高各年龄段的存活率,是丰富的保健食品资源。  相似文献   
14.
为了提高留胚米的稳定性,采用紫外照射对留胚米进行稳定化处理。采用单因素实验及响应面分析研究紫外照射对留胚米脂肪酶灭活率的影响,同时考察留胚米水分损失率、碎米率和爆腰率的变化。结果表明:紫外照射最佳条件是照射时间11.50min,照射距离为4.5cm,初始水分含量13%,此时脂肪酶灭活率66.73%、且碎米率增加0.12%、爆腰率增加1.63%、水分散失率增加0.38%,处于可以接受范围内,因此可以选为紫外照射稳定留胚米的工艺参数。  相似文献   
15.
用微波消解技术对小麦胚芽进行前处理,然后用磷钼蓝分光光度法测定了其磷含量。使用微波消解炉,实验结果表明:该法操作简单、试剂用量少、重现性好,用微波消解技术大大缩短了样品前处理的时间,适于食品中磷元素含量的测定。  相似文献   
16.
郭卓雨  高丽萍  李贞 《食品科学》2014,35(1):234-238
目的: 探讨葡萄籽原花青素( g r a p e s e e d p r o a n t h o c y a n i d i n , G S P E ) 对顺铂(cis-diamminedichloroplatinum,CDDP)诱导人胚肾细胞HEK293凋亡及相关凋亡基因的影响,并探讨可能的机制。方法:体外培养正常HEK293细胞,噻唑蓝法测定GSPE、CDDP分别对HEK293细胞生长的影响以及GSPE对CDDP诱导HEK293细胞毒性的保护作用,流式细胞仪测定GSPE对CDDP所致HEK293细胞凋亡率的变化,Western blotting测定GSPE对CDDP所致HEK293细胞凋亡相关基因Bax、Bcl-2蛋白表达的影响。结果:GSPE对CDDP所致HEK293细胞毒性具有拮抗作用,可减轻CDDP所致HEK293细胞凋亡,减弱Bax表达、增强Bcl-2表达。结论:GSPE对CDDP所致HEK293细胞凋亡具有拮抗作用,其机制可能与GSPE降低促凋亡基因Bax,升高抗凋亡基因Bcl-2的表达有关。  相似文献   
17.
张璐  舒国伟  彭丹 《食品科技》2006,(10):231-233
以大豆胚芽出油率为指标,石油醚为脱脂溶剂,通过单因素和正交试验对大豆胚芽索氏提取工艺进行了研究,并用气相色谱对胚芽油的脂肪酸组成进行了分析。结果表明,大豆胚芽制油的最佳提取工艺为:粒度30目、料液比1:12、回流时间5h,在此条件下,大豆胚芽出油率为10.50%,其主要组成为亚麻酸20.73%、亚油酸52.21%、油酸10.51%、棕榈酸为13.47%。  相似文献   
18.
采用不同培养基对女贞子的胚进行培养,并对其幼苗的叶片和嫩茎进行愈伤组织诱导.结果表明,在胚的萌发诱导中,以MS+1.00 mg·L-1 6-BA培养时,女贞子幼苗的叶长和根长最长;以MS+1.50 mg·L-1 6-BA培养时,女贞子幼苗的茎高最高;MS+1.50 mg·L-1 6-BA+0.30 mg·L-1 2,4...  相似文献   
19.
Mammalian oocytes can reprogram differentiated somatic cells into a totipotent state through somatic cell nuclear transfer (SCNT), which is known as cloning. Although many mammalian species have been successfully cloned, the majority of cloned embryos failed to develop to term, resulting in the overall cloning efficiency being still low. There are many factors contributing to the cloning success. Aberrant epigenetic reprogramming is a major cause for the developmental failure of cloned embryos and abnormalities in the cloned offspring. Numerous research groups attempted multiple strategies to technically improve each step of the SCNT procedure and rescue abnormal epigenetic reprogramming by modulating DNA methylation and histone modifications, overexpression or repression of embryonic-related genes, etc. Here, we review the recent approaches for technical SCNT improvement and ameliorating epigenetic modifications in donor cells, oocytes, and cloned embryos in order to enhance cloning efficiency.  相似文献   
20.
Similar to environmental factors, EDCs (endocrine-disrupting chemicals) can influence gene expression without modifying the DNA sequence. It is commonly accepted that the transgenerational inheritance of parentally acquired traits is conveyed by epigenetic alterations also known as “epimutations”. DNA methylation, acetylation, histone modification, RNA-mediated effects and extracellular vesicle effects are the mechanisms that have been described so far to be responsible for these epimutations. They may lead to the transgenerational inheritance of diverse phenotypes in the progeny when they occur in the germ cells of an affected individual. While EDC-induced health effects have dramatically increased over the past decade, limited effects on sperm epigenetics have been described. However, there has been a gain of interest in this issue in recent years. The gametes (sperm and oocyte) represent targets for EDCs and thus a route for environmentally induced changes over several generations. This review aims at providing an overview of the epigenetic mechanisms that might be implicated in this transgenerational inheritance.  相似文献   
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