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171.
醋酸菌筛选培养基的优化和优良醋酸菌分离的研究   总被引:18,自引:11,他引:18  
以大米糖化汁培养基为筛选培养基,从市售的醋酸菌粉和武汉锦春调味品厂的醋醅中分离得到了8株产酸快,转化率高的醋酸菌,并以其中的3株试制木瓜果醋取得了良好的效果。结果表明,以大米糖化汁培养基作为醋酸菌的筛选培养基,易操作,筛选效果好,优于其它的醋酸菌筛选培养基。  相似文献   
172.
Drought and salinity stresses are significant abiotic factors that limit rice yield. Exploring the co-response mechanism to drought and salt stress will be conducive to future rice breeding. A total of 1748 drought and salt co-responsive genes were screened, most of which are enriched in plant hormone signal transduction, protein processing in the endoplasmic reticulum, and the MAPK signaling pathways. We performed gene-coding sequence haplotype (gcHap) network analysis on nine important genes out of the total amount, which showed significant differences between the Xian/indica and Geng/japonica population. These genes were combined with related pathways, resulting in an interesting mechanistic draft called the ‘gcHap-network pathway’. Meanwhile, we collected a lot of drought and salt breeding varieties, especially the introgression lines (ILs) with HHZ as the parent, which contained the above-mentioned nine genes. This might imply that these ILs have the potential to improve the tolerance to drought and salt. In this paper, we focus on the relationship of drought and salt co-response gene gcHaps and their related pathways using a novel angle. The haplotype network will be helpful to explore the desired haplotypes that can be implemented in haplotype-based breeding programs.  相似文献   
173.
Heat shock factors (Hsfs) play pivotal roles in plant stress responses and confer stress tolerance. However, the functions of several Hsfs in rice (Oryza sativa L.) are not yet known. In this study, genome-wide analysis of the Hsf gene family in rice was performed. A total of 25 OsHsf genes were identified, which could be clearly clustered into three major groups, A, B, and C, based on the characteristics of the sequences. Bioinformatics analysis showed that tandem duplication and fragment replication were two important driving forces in the process of evolution and expansion of the OsHsf family genes. Both OsHsfB4b and OsHsfB4d showed strong responses to the stress treatment. The results of subcellular localization showed that the OsHsfB4b protein was in the nucleus whereas the OsHsfB4d protein was located in both the nucleus and cytoplasm. Over-expression of the OsHsfB4b gene in Arabidopsis and rice can increase the resistance to drought stress. This study provides a basis for understanding the function and evolutionary history of the OsHsf gene family, enriching our knowledge of understanding the biological functions of OsHsfB4b and OsHsfB4d genes involved in the stress response in rice, and also reveals the potential value of OsHsfB4b in rice environmental adaptation improvement.  相似文献   
174.
张科 《山东化工》2007,36(1):18-20
高吸水保水剂是一种新型的功能高分子材料,由于其特殊的化学成分、物理结构和吸水性能,使其在农林园艺、医疗卫生、工业工程、日常生活、食品保鲜加工等领域得到了广泛的应用。  相似文献   
175.
田间试验结果显示:23%宝穗胶悬对水稻纹枯病有较好的防治效果。在杂交稻上应用10~20ml/667m∧2,其防效在80%~95%,且持效期长达1个月,显著优于目前大面积使用的井冈霉素等药剂。试验还表明:在粳稻上最佳应用适期在粳稻抽穗前20天。  相似文献   
176.
177.
Rice bran is a rich source of nutrients and nutraceuticals, which has bio-functional properties. De-oiled rice bran, a major byproduct of rice bran oil industry, is not yet efficiently utilized for human consumption due to its poor edible quality. Various physical processing methods like sieving, pin milling and air classification were applied to upgrade the quality of bran and also to investigate its effect on particle size distribution, content of ash, protein, total dietary fiber, insoluble fiber, soluble fiber and oryzanol as well as total antioxidant activity in bran fractions. Sieve separation resulted in an increase in the content of protein and bio-functional components like soluble fiber and oryzanol as well as total antioxidant activity. Pin milling and sieving resulted in smaller particle size fraction without loss in the content of protein and other bio-functional components and antioxidant activity. Air classification of this material resulted in significant decrease in ash content with moderate increase in protein content and significant increase in the contents of oryzanol and soluble fiber and the total antioxidant activity. This resulted in quality improvement of commercial de-oiled bran viz., reduction in coarse bran fraction (>250μm size particles) from 65% to 0%, content of ash from 14.3 to 13.1 g/100 g, and insoluble fiber from 49.3 to 46.1 g/100 g, and increase in the content of protein from 13.7 to 17 g/100 g, soluble fiber from 2.75 to 4.35 g/100 g, oryzanol from 13.6 to 18.1 mg/100 g, and total antioxidant activity from 61 to 96 mM α-tocopherol equivalent/g. About 30% edible and nutrient rich rice bran, which can be used as an ingredient in the bakery products and health food formulations, was obtained from unutilized commercial de-oiled bran by this process.  相似文献   
178.
高永强  李娜 《酿酒》2010,37(2):83-85
从传统黄酒生产的淋饭酒母中分离出酵母,并对纯化的酵母菌株的培养条件进行了研究。试验结果表明:适宜培养温度是28~30℃,适宜发酵pH为4.5~6.0。  相似文献   
179.
An investigation was carried out in a circulating fluidized bed to explore if rice husk could be fluidized without mixing it with any foreign solids. Experimental results indicate that bed cross‐section has an important influence on the fluidization characteristics of rice husk. Larger the cross‐section, easier it is to fluidize the husk without slugging. Particle size, sphericity, bulk density, and transport velocity of husk were measured. The riser was operated under bubbling bed regimes. Efforts were made to measure the minimum fluidization velocity by varying the bed depth and cross‐section.  相似文献   
180.
针对大型风力机叶片气弹振动问题,提出一种基于脉冲响应的大型风力机柔性叶片结构阻尼有效分析方法.采用一种5自由度的超级单元,将柔性叶片离散成由若干超级单元构成的多体系统,基于计算多体系统动力学中的R-W方法建立了叶片的动力响应模型.以美国可再生能源实验室(NREL)发布的5 MW近海风力机叶片为研究对象,通过分析叶片在脉冲激励下的动力学响应得到其传递函数,由半功率带宽法计算叶片在静止和运转工况下的挥舞与摆振结构阻尼,从而为确定叶片气弹稳定性的边界提供依据.该研究对于指导叶片结构与气动外形设计、帮助确定其气弹稳定性边界具有重要意义.  相似文献   
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