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2.
从采油菌剂及原油中共分离出11株细菌,并对其发酵特性和生理生化特性进行研究。结果表明,分离菌株可以利用石蜡产表面活性物质,但不产气;菌株发酵液的pH值没有明显的变化,对原油有不同程度的乳化作用;Y-1和Y-5为芽孢杆菌属(Bacillus),Y-2和Y-6为节杆菌属(Arthrobacter),Y-3为棒杆菌属(Corynebacterium),Y-4、J-1、J-2、J-4、J-5和J-6为不动杆菌属(Acinetobacter)。大多数分离菌株为兼性厌氧菌,具有运动性,不产生硫化氢,能够利用蔗糖、葡萄糖等廉价碳源产生有机酸和气体,这些特性有利于菌株应用于微生物采油。 相似文献
3.
高产人参发根系的建立及发根中皂苷Rb_1的分离纯化 总被引:1,自引:1,他引:1
利用发根农杆菌A4菌株在2年生人参根外植体上直接诱导产生人参发根。对16个人参发根系比生长速率及人参总皂苷含量进行测定,得到3个具有较高比生长速率和人参皂苷含量的发根系。其中发根系R9923具有最高的比生长速率,在连续培养4周后生长量比最初提高了28.8倍。研究R9923发根系的生长曲线和皂苷含量变化规律发现,随着发根生物量的增加,发根中皂苷含量积累得也越多。利用HPLC法测定了R9923发根系中单体皂苷Rg1、Re、Rb1的含量。生长4周的人参发根总皂苷含量达15.2 mg/g,其中人参皂苷Rb1的含量为68.3%,比3年生栽培人参中Rb1含量高1.3倍,可以用于大规模培养。用硅胶柱层析法从人参发根总皂苷中分离提纯人参皂苷Rb1,当洗脱剂中氯仿∶甲醇=7.5∶2.5(体积比)时洗脱效果较好。用硅胶柱法提取的皂苷Rb1纯度为89.95%,得率为72.7%。 相似文献
4.
The group of conjugated fatty acids known as conjugated linoleic acid (CLA) isomers have been extensively studied with regard to their bioactive potential in treating some of the most prominent human health malignancies. However, CLA isomers are not the only group of potentially bioactive conjugated fatty acids currently undergoing study. In this regard, isomers of conjugated α‐linolenic acid, conjugated nonadecadienoic acid and conjugated eicosapentaenoic acid, to name but a few, have undergone experimental assessment. These studies have indicated many of these conjugated fatty acid isomers commonly possess anti‐carcinogenic, anti‐adipogenic, anti‐inflammatory and immune modulating properties, a number of which will be discussed in this review. The mechanisms through which these bioactivities are mediated have not yet been fully elucidated. However, existing evidence indicates that these fatty acids may play a role in modulating the expression of several oncogenes, cell cycle regulators, and genes associated with energy metabolism. Despite such bioactive potential, interest in these conjugated fatty acids has remained low relative to the CLA isomers. This may be partly attributed to the relatively recent emergence of these fatty acids as bioactives, but also due to a lack of awareness regarding sources from which they can be produced. In this review, we will also highlight the common sources of these conjugated fatty acids, including plants, algae, microbes and chemosynthesis. 相似文献
5.
Low n-6/n-3 PUFA Ratio Improves Lipid Metabolism,Inflammation, Oxidative Stress and Endothelial Function in Rats Using Plant Oils as n-3 Fatty Acid Source 下载免费PDF全文
Li Gang Yang Zhi Xiu Song Hong Yin Yan Yan Wang Guo Fang Shu Hui Xia Lu Shao Kang Wang Gui Ju Sun 《Lipids》2016,51(1):49-59
Lipid metabolism, inflammation, oxidative stress and endothelial function play important roles in the pathogenesis of cardiovascular disease (CVD), which may be affected by an imbalance in the n‐6/n‐3 polyunsaturated fatty acid (PUFA) ratio. This study aimed to investigate the effects of the n‐6/n‐3 PUFA ratio on these cardiovascular risk factors in rats fed a high‐fat diet using plant oils as the main n‐3 PUFA source. The 1:1 and 5:1 ratio groups had significantly decreased serum levels of total cholesterol, low‐density lipoprotein cholesterol, and proinflammatory cytokines compared with the 20:1 group (p < 0.05). Additionally, the 20:1 group had significantly increased serum levels of E‐Selectin, von Willebrand factor (vWF), and numerous markers of oxidative stress compared with the other groups (p < 0.05). The 1:1 group had a significantly decreased lipid peroxide level compared with the other groups (p < 0.05). Serum levels of malondialdehyde, reactive oxygen species and vWF tended to increase with n‐6/n‐3 PUFA ratios increasing from 5:1 to 20:1. We demonstrated that low n‐6/n‐3 PUFA ratio (1:1 and 5:1) had a beneficial effect on cardiovascular risk factors by enhancing favorable lipid profiles, having anti‐inflammatory and anti‐oxidative stress effects, and improving endothelial function. A high n‐6/n‐3 PUFA ratio (20:1) had adverse effects. Our results indicated that low n‐6/n‐3 PUFA ratios exerted beneficial cardiovascular effects, suggesting that plant oils could be used as a source of n‐3 fatty acids to prevent CVD. They also suggested that we should be aware of possible adverse effects from excessive n‐3 PUFA. 相似文献
6.
Ecto-ATPase (ecto-adenosine triphosphatase), a key enzyme of cardiac metabolism, is responsible for modulation of the concentration of extracellular nucleotides in the heart. We present methodology consisting of the combined use of biochemical and histocytochemical techniques to study its properties. Using samples from essentially the same preparation, we applied biochemistry and histocytochemistry to determine biochemical characteristics of ecto-ATPase and an in situ localization of its reactivity. Our results indicated that detected enzyme resists fixation, depends on divalent ions, and hydrolyzes ATP, but not AMP or ADP-beta-S. Reaction product of the enzyme activity was found confined to the extracellular surface of the plasma membrane of cardiac myocytes and endothelial cells due to the corresponding orientation of the enzyme active sites. Experiments using an inhibitor justified specificity of the reaction. When used together with molecular biological and immunocytochemical techniques, the present methodological approach should be capable of yielding important information about the actual ability of ecto-ATPase to operate. 相似文献
7.
With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship's ballast water. The surface morphology of Al2O3 dielectric layer was analysed using Atomic Force Microscopy (AFM), where the size of Al2O3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship's ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase (CAT), Peroxidase (POD) and Superoxide dismutase (SOD). In addition, the quality of the ballast water was greatly improved. 相似文献
8.
炸药废水处理技术研究概述 总被引:2,自引:0,他引:2
炸药废水含有多种毒性物质,对环境造成严重的局部污染,威胁人类的健康与生存。本文介绍了炸药废水的处理方法,包括化学处理方法、物理处理方法和生化处理方法,并对今后的研究发展作出展望。 相似文献
9.
人参皂苷Rb1单克隆抗体的制备与鉴定 总被引:2,自引:1,他引:2
用人参皂苷Rb1分别与牛血清白蛋白(BSA)和卵清蛋白(OVA)反应合成了交联抗原GRb1-BSA(GRb1与BSA的结合比为10∶1)和GRb1-OVA(GRb1与OVA的结合比为8∶1)。以GRb1-BSA为免疫原,分5次免疫3只BALB/C小鼠,取免疫脾细胞与小鼠骨髓瘤细胞进行融合,Hat筛选,有限稀释法克隆。建立分泌单克隆抗体的杂交瘤细胞系。采用ELISA(酶联免疫吸附测定)间接法和竞争法检测抗体的特异性。结果获得了一只小鼠分泌抗体效价达1∶16000,并获得两株分泌GRb1的单克隆抗体的细胞系,分别命名为1F7和1G3,单抗检测显示在0.01~1μg/mL呈线性关系,GRb1的检测范围达50~350 ng/mL,两株单抗针对相同的抗原决定簇,制备的单克隆抗体可用于GRb1含量的检测和分离。 相似文献
10.
采用液体深层培养方式,研究了中药薏苡仁水提醇溶物(EEC)对灵芝的细胞生长、活性物质产量和清除自由基能力的影响。结果表明:薏苡仁提取物在添加剂量分别为6、10和14 mg.L-1时,灵芝生物量、灵芝多糖和灵芝酸的产量分别提高到10.19±0.51、0.72±0.03和0.12±0.01 g.L-1;与未添加薏苡仁提取物的对照相比,分别提高了14.6%、34.21%和254.2%。另外,薏苡仁提取物在添加剂量为14 mg.L-1时,对灵芝清除两种自由基活性都有促进作用,尤其是超氧阴离子比对照提高了61.6%。结果表明:薏苡仁提取物EEC可显著促进灵芝细胞生长和产物形成,并增强灵芝提取物清除自由基的能力。 相似文献