排序方式: 共有12条查询结果,搜索用时 31 毫秒
1.
Inhibin is a heterodimeric glycoprotein hormone involved in the regulation of FSH release from the anterior pituitary gland and it has been characterized from various animals. Although, multiple molecular forms of inhibin have been reported from different species, however, the molecular nature of inhibin has not been studied in buffaloes. In the present study, attempts were made to identify inhibin in buffalo ovarian follicular fluid. Buffalo ovaries were obtained from the local abattoir and follicular fluid was aspirated from surface follicle (with diameter ?5 mm). A combination of techniques (viz., gel filtration, SDS-PAGE, Western blot etc.) was employed for identification and isolation of inhibin(s). Inhibin bands were detected at 129 and 63 kDa by Western blot analysis in non-reducing conditions. In reduced SDS-PAGE, 63 kDa fraction produced a single band while 129 kDa fraction resolved into four components of 63, 43, 29 and 20 kDa. Out of them only 29, 63 and the native 129 kDa fractions produced bands on Western blot analysis. In total five fractions (63, 54, 39, 29, 25 kDa) were obtained by trypsin digestion of 129 kDa form. However, only 63 and 29 kDa fractions showed immunoreactivity. In this study, for the first time, we have identified two major forms of inhibin (129 and 63 kDa) with little proteolytic cleavage/processing of the large precursor in the buffalo follicular fluid. 相似文献
2.
Proteolytic degradation of barley proteins is examined in green (unkilned) malt and germinating seeds from Hordeum vulgare L. cv. Harrington. Zymographic analysis of the Harrington green malt extracts using commercial preparations of barley beta-amylase incorporated as a proteolytic substrate in 2-D SDS gels shows multiple proteolytic activities. A developmental study shows that the several green malt beta-amylase-degrading activities appear at around day 2 of germination. The several activities appear to increase and decrease through 7 days of germination in a coordinated fashion. Gels treated with class-specific proteinase inhibitors show that serine-class proteinase activities are responsible for barley beta-amylase degradation seen on the zymograms. Western blot analysis also shows that proteolytic enzymes recovered from 1-D electrophoretic gels degrade barley beta-amylase, and that the degradation is inhibited by PMSF. This is the first demonstration that malt proteinases are capable of degrading important metabolic enzymes in germinating barley, and the first postulated physiological role for the serine class proteinases in barley malt. 相似文献
3.
F-box蛋白是一类含有F-box结构域,在泛素介导的蛋白质水解过程中具有底物识别特性的蛋白质家族。这类蛋白质在细胞循环、信号传导、基因转录、雄性不育和细胞程序化死亡等多种生理过程中发挥重要作用。介绍了已知的植物F-box蛋白质的生物学功能并对F-box基因的系统进化进行了分析。 相似文献
4.
5.
强化高温成熟缩短工艺时间对干腌火腿蛋白质水解的影响 总被引:1,自引:0,他引:1
传统金华火腿工艺时间延续8~10个月,后期须经过7~8月份35~37℃高温天气的高温成熟才能形成其特殊风味。为有效缩短火腿发酵成熟工艺时间,在前期试验基础上采用"强化高温成熟(35~37℃、25~30d)"措施,以火腿中蛋白质水解形成的游离氨基酸总量为目标,组织了发酵成熟时间、温度、湿度等因素的正交试验并予以优化,结果表明:火腿中游离氨基酸总量与发酵成熟温度的提高呈正相关(R2=0.7361),与传统工艺相比,随工艺时间的延长保持持续增长(p<0.01);游离氨基酸日增量在发酵成熟中期达到最高水平,且在成熟后期维持较高水平;成熟结束游离氨基酸总量已达到传统工艺的86.79%,风味感官评定80d成熟产品风味达到传统一级火腿水平,说明强化并延长后期的高温(35~37℃)成熟时间能有效促进火腿中蛋白质水解和风味形成,显著缩短发酵成熟工艺的延续时间。 相似文献
6.
7.
8.
Sanna Luoto Zhongqing Jiang Outi Brinck Tuula Sontag-Strohm Päivi Kanerva Maaike Bruins Luppo Edens Hannu Salovaara Jussi Loponen 《Journal of Cereal Science》2012
Cereal based products intended for gluten sensitive individuals, particularly to celiac disease patients, tend to have poor organoleptic qualities and they contain low levels of healthy whole grain compounds. Adding whole grain ingredients, such as malt hydrolysates, could compensate these defects provided that the ingredients are adequately free from toxic prolamin epitopes. Here we demonstrate that the level of toxic prolamin epitopes in the malt autolysates (wheat, barley, rye) were substantially lower than in the native malts but too high to allow “very low in gluten” labelling. To further eliminate the residual levels of toxic prolamin epitopes, a proline-specific endoprotease from Aspergillus niger was added to the malt autolysates. In the resulting malt hydrolysates (of wheat and rye but not barley), the prolamins were indeed greatly reduced and were below the very low gluten limit of 100 mg/kg. Malt hydrolysates with adequately low gluten levels may potentially be used as novel ingredients within gluten-free foods. 相似文献
9.
[目的]优化麦芽的糖化工艺条件,探究麦芽的水解作用规律,获得发酵优良的麦汁。[方法]以还原糖、总糖、α-氨基氮和可溶性蛋白质的含量为指标,探究麦芽蛋白质休止温度、糖化的温度、时间、初始pH等工艺参数对麦芽淀粉和蛋白质水解的影响。[结果]糖化温度是影响麦芽淀粉水解的主要因素;蛋白质休止温度、时间及初始pH是影响麦芽蛋白质水解的主要因素。麦芽糖化工艺优化结果:50℃蛋白质休止1 h,65℃糖化40 min,72℃糖化20 min,初始pH为5.0。该工艺制备的麦汁15℃发酵的酒精度达6.2%,实际发酵度达75.3%。[结论]该研究可为不同类型啤酒酿造制备特定的麦汁提供生产依据。 相似文献
10.