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目的 :监测和评估复合益生菌制剂“海生元”在制备、保存和使用过程中微生物污染状况 ,消除对健康造成潜在不良影响的危险。方法 :在有效期 (1年 )和保存 2 4个月 (2年 )时 ,定期随机对“海生元”口服液和胶囊取样 ,按常规方法进行微生物限度检验 ,包括细菌总数、大肠菌群、致病菌检查及霉菌、酵母菌计数。结果 :(1)贮存 12个月时微生物限度检验结果显示 :口服液各项指标均为阴性。胶囊剂分别为细菌数 <2× 10CFU/ g ,大肠菌群数 <3MPN/ 10 0 g、真菌和酵母菌总数分别 <5CFU/g ,未检出致病菌。 (2 )储存 2 4个月时的微生物限度检验结果显示 :口服液细菌总数、霉菌数和酵母菌数均 <1CFU/ g ,大肠菌数 <3MPN/ 10 0 g。胶囊剂细菌总数 <4× 10 3 CFU/ g ,大肠菌数 <30MPN/ 10 0g ,霉菌和酵母菌数 <10CFU/ g ,未检出致病菌。结论 :复合益生菌制剂“海生元”2种剂型 (口服液和胶囊 )在效期内的染菌情况均符合规定限度要求。在普通条件下储存 2 4个月 (2年 ) ,仅对胶囊的细菌总数略有影响 ,但结果仍符合中国药典规定的限度标准。本实验结果证实了复合益生菌制剂制备、储存过程中卫生安全的可靠性。 相似文献
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应用微生物降低鸡粪N营养元素损失, 促进其无害化进程 总被引:1,自引:1,他引:0
为减轻大量禽畜废弃物对环境的污染, 将其资源化为优质的无害化有机肥料, 研究了微生物F468对降低鸡粪N营养元素损失和促进其无害化进程的影响。结果表明, 继代80次, F468降低鸡粪氨气挥发的能力无显著变化, 能降低鸡粪79%的N元素损失。F468还能通过降低蛔虫卵和粪肠杆菌的数量, 促进鸡粪的无害化进程。不添加F468, 蛔虫卵和粪肠杆菌达到我国无害化标准(NY884-2004)的时间分别需要25 d和20 d。加入F468后, 蛔虫卵和粪肠杆菌达到我国无害化标准的时间分别需要15 d和10 d, 均比不加微生物提前10 d达到我国无害化标准。 相似文献
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微生物基因组空缺区域(Gap)中可能存在重要的生物学信息,如果无法补齐所有Gap,不仅不能获得完整的基因组图谱,还会给后续的基因组信息解读造成很大困难。而基因组空缺区域填充(Gap closure)是获得微生物基因组完成图的关键,本文结合作者以及借鉴上海人类基因组研究中心在微生物基因组Gap closure中的经验,针对微生物基因组Gap closure常用的6种策略:参考序列比对、多引物PCR、基因组步移、基因组文库克隆末端测序、末端配对(Paired-End)以及基因组光学图谱技术进行综述。 相似文献
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A Belarbi C Hachet A-C Helfer S Gognies A Gainvors 《Journal of industrial microbiology & biotechnology》2000,24(4):296-300
Zymograms of a crude protein extract from S. cerevisiae strain SCPP containing endopolygalacturonase were studied and compared to the purified enzyme by determining their physico-chemical
properties. The results obtained with crude extract were similar to those of the purified enzyme. The endopolygalacturonase
from both sources displayed a pH optimum between 3.0 and 4.0, and was active at temperatures between 4 and 50°C on a large
panel of substrates. These characteristics make this S. cerevisiae endopolygalacturonase an attractive tool for the beverage industry. Journal of Industrial Microbiology & Biotechnology (2000) 24, 296–300.
Received 24 September 1999/ Accepted in revised form 29 January 2000 相似文献
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Soil minerals and humic acids alter enzyme stability: implications for ecosystem processes 总被引:1,自引:0,他引:1
Steven D. Allison 《Biogeochemistry》2006,81(3):361-373
In most ecosystems, the degradation of complex organic material depends on extracellular enzymes produced by microbes. These enzymes can exist in bound or free form within the soil, but the dynamics of these different enzyme pools remain uncertain. To address this uncertainty, I determined rates of enzyme turnover in a volcanic soil with and without added enzymes. I also tested whether or not soil minerals and humic acids would alter enzyme activity. In soils that were gamma-irradiated to stop enzyme production, 35–70% of the enzyme activity was stable throughout the 21-day incubation. The remaining enzyme fraction decayed at rates ranging from − 0.032 to − 0.628 day−1. In both the irradiated soils and in soils with added enzymes, addition of the mineral allophane had a strong positive effect on most enzyme activities. Another added mineral, ferrihydrite, had a weak positive effect on some enzymes. Added humic acids strongly inhibited enzyme activity. These findings suggest that minerals, especially allophane, enhance potential enzyme activities in young volcanic soils. However, the actual activity and function of these enzymes may be low under field conditions if stabilization results in less efficient enzyme-substrate interactions. If this is the case, then much of the measured enzyme activity in bulk soil may be stabilized but unlikely to contribute greatly to ecosystem processes. 相似文献
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Patrick J. Cummings Ray Ahmed Jeffrey A. Durocher Adam Jessen Tamar Vardi Kristina M. Obom 《Journal of visualized experiments : JoVE》2013,(78)
Pyrosequencing is a versatile technique that facilitates microbial genome sequencing that can be used to identify bacterial species, discriminate bacterial strains and detect genetic mutations that confer resistance to anti-microbial agents. The advantages of pyrosequencing for microbiology applications include rapid and reliable high-throughput screening and accurate identification of microbes and microbial genome mutations. Pyrosequencing involves sequencing of DNA by synthesizing the complementary strand a single base at a time, while determining the specific nucleotide being incorporated during the synthesis reaction. The reaction occurs on immobilized single stranded template DNA where the four deoxyribonucleotides (dNTP) are added sequentially and the unincorporated dNTPs are enzymatically degraded before addition of the next dNTP to the synthesis reaction. Detection of the specific base incorporated into the template is monitored by generation of chemiluminescent signals. The order of dNTPs that produce the chemiluminescent signals determines the DNA sequence of the template. The real-time sequencing capability of pyrosequencing technology enables rapid microbial identification in a single assay. In addition, the pyrosequencing instrument, can analyze the full genetic diversity of anti-microbial drug resistance, including typing of SNPs, point mutations, insertions, and deletions, as well as quantification of multiple gene copies that may occur in some anti-microbial resistance patterns. 相似文献