胡桃醌对大肠杆菌呼吸及能量代谢的影响

近年来有研究显示胡桃醌对细菌具有一定的抑制作用,但其对细菌的抑茵机理尚不明确.文章从胡桃醌对大肠杆菌呼吸和能量代谢的影响来揭示其押菌机理.分别对培养基中溶氧量、葡萄糖含量、细胞内ATP含量及ATP酶活性进行测定.结果表明:在最低抑菌浓度(MIC)下,培养基中的溶氧量略微下降,8h后趋于恒定,溶氧量共下降了24.2％,而乙醇对照(CK2)下降了39.4％;培养基中的葡萄糖含量先下降后上升,葡萄糖含量增加9.1％,而CK2则下降6.4％;菌体内的ATP含量先是剧烈下降,然后缓慢上升,4h后趋于恒定,MIC时下降最少;ATP酶活性起先略有下降,随后上升,MIC时上升的最少,而后又略有下降,显示出一定的波动性.以上结果说明随着时间增大,不同浓度的胡桃醌对大肠杆菌的呼吸和能量代谢均有一定影响.     

Development of biocontrol agents from food microbial isolates for controlling post-harvest peach brown rot caused by Monilinia fructicola

An unconventional strategy of screening food microbes for biocontrol activity was used to develop biocontrol agents for controlling post-harvest peach brown rot caused by Monilinia fructicola. Forty-four microbial isolates were first screened for their biocontrol activity on apple fruit. Compared with the pathogen-only check, seven of the 44 isolates reduced brown rot incidence by >50%, including four bacteria: Bacillus sp. C06, Lactobacillus sp. C03-b and Bacillus sp. T03-c, Lactobacillus sp. P02 and three yeasts: Saccharomyces delbrueckii A50, S. cerevisiae YE-5 and S. cerevisiae A41. Eight microbial isolates were selected for testing on peaches by wound co-inoculation with mixtures of individual microbial cultures and conidial suspension of M. fructicola. Only two of them showed significant biocontrol activity after five days of incubation at 22 degrees C. Bacillus sp. C06 suppressed brown rot incidence by 92% and reduced lesion diameter by 88% compared to the pathogen-only check. Bacillus sp.T03-c reduced incidence and lesion diameter by 40% and 62%, respectively. The two isolates were compared with Pseudomonas syringae MA-4, a biocontrol agent for post-harvest peach diseases, by immersing peaches in an aliquot containing individual microbial isolates and the pathogen conidia. Treatments with isolates MA-4, C06 and T03-c significantly controlled brown rot by 91, 100, and 100% respectively. However, only isolates MA-4 and C06 significantly reduced brown rot by 80% and 15%, respectively when bacterial cells alone were applied. On naturally infected peaches, both the bacterial culture and its cell-free filtrate of the isolate C06 significantly controlled peach decay resulting in 77 and 90% reduction, respectively, whereas the treatment using only the bacterial cells generally had no effect. Isolate C06 is a single colony isolate obtained from a mesophilic cheese starter, and has been identified belonging to Bacillus amyloliquefaciens. The results have clearly demonstrated that isolate C06 has a great potential for being developed into a biocontrol agent.     

纤维堆囊菌产埃博霉素B发酵培养基的优化

目的优化埃博霉素B发酵培养基。方法以纤维堆囊菌SoF5—9为供试菌株,通过单因素和止交试验研究了埃博霉素B合成的最佳培养基。结果埃博霉素B最适发酵培养基为糊精0．3%,蔗糖0．07％,葡萄糖0．02％,豆饼粉0．17％,MgSO4·7H200．1‰无水氯化钙0．1％,EDTA．Fe^（3＋）2mL／L,微量元素（TE）0．5mL／L。在该最优条件下,埃博霉素B产量可达到27．5mg／L。结论合理优化发酵培养基组分可以有效提高埃博霉素B的产量。     

激情的拉图兹

伴随着意大利设计文化半个世纪的辉煌,拉图兹（Natuzzi）凭借其在家居领域的杰出地位,其品牌荣耀历久弥新,不仅意味着家居文化的精髓传承,更意味着美与审美的交流互动与美好而优雅生活的纵情表达。     

膨润土负载Co(salen)催化转化硫酸盐木素的研究

比较研究Co(salen)催化剂、膨润土负载Co(salen)催化剂催化降解硫酸盐木素的结构变化与降解产物。膨润土负载Co(salen)促进硫酸盐木素产生C=O,进一步促进苯环、-OCH3、醚键的降解。通过GC-MS分析,发现膨润土负载Co(salen)催化降解硫酸盐木素产生更多的产物。     

三维蜂窝状格栅编织物的设计

基于对四步三维编织法的研究,提出一种蜂窝状格栅编织物的三维编织方法及其制作技术,并进行了编织试验。该方法形成的整体蜂窝状编织物不但融合了网状织物的质轻和编织物的三维结构的优点,而且实现方便,对现有三维编织机器改动较少。     

Structural characterisation of a water-soluble polysaccharide with high branches from the leaves of Taxus chinensis var. mairei

A large number of polysaccharides present in the leaves of Taxus chinensis var. mairei were successively extracted with hot water after preliminary treatments. The ion-exchange and gel-permeation chromatography was used to isolate and purify the major polysaccharides to afford a complex water-soluble polysaccharide, named T1 with a molecular mass of 3.44 × 10⁶ Da determined by HPGPC. T1 consisted of 2,4-di-O-methyl-mannose, rhamnose, arabinose, xylose, galactose, mannose, galacturonic acid and glucuronic acid in a molar ratio of 2:5:24:9:3:46:1:10, and the acetyl content was estimated to be 2.1%. On the basis of methylation analysis, periodate and chromium trioxide oxidations, Smith degradation, graded acid hydrolysis, and NMR and IR spectroscopy, T1 possessed a 1,3,6-linked β-d-Manp main chain, substituted by mannose, arabinose, galactose, xylose, rhamnose, 2,4-di-O-methyl-mannose, galacturonic acid, and glucuronic acid residues. These contained non-reducing end-units of mannose, arabinose, xylose, 2,4-di-O-methyl-mannose, and glucuronic acid. This is the first report on isolation of an acid heteropolysaccharide from Taxus species.     

羽毛球运动短裤功能分割线设计与研究

分割线设计是运动服装设计中经常采用的手段。探讨了功能性分割线在羽毛球运动短裤中的运用原则与方法。先设计几款短裤进行人体穿着试验,根据试验结果选择一款短裤作为基本款,再在此基本款的基础之上根据人体静态和动态特征设计不同位置的分割线,并采用主客观相结合的方法进行评价,得出:羽毛球运动短裤功能分割线的设计要考虑分割线位置、数量;不同位置的分割线会有牵制作用;可利用斜丝面料增加短裤的运动性能。     

精梳长绒棉彩色棉铜氢纤维混纺针织纱的开发

介绍了铜氨纤维的特性，铜氨纤维与棉纤维混和纺制针织用纱的工艺方案是采用三道并条的工艺。铜氨纤维纺纱在开清棉工序以多松少打、多梳少落为工艺原则，为减少纤维损伤及打手返花，造成过多的棉结，适当降低打手速度，并跳过A036B型豪猪开棉机，减少打击点。     

一种新的用于数据挖掘工具的网页净化算法

为了更好地消除网页噪声,有效地提取网页的主题内容,提出了一种新的网页净化算法.该算法认为网页的主题内容主要包含在标记和

标记里面,并据此对网页噪声进行预处理,然后与相关网页进行内容匹配,通过计算节点重要度,获取网页的主题内容.对门户网站的6 318个网页的检测表明,该算法可以有效地提取网页的主题内容,准确率达到98.2%以上.用于数据挖掘工具时,该算法优于其他同类算法,可以有效地去除网页噪声.     

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