K-B法药敏试验中菌液量的规范

目的 :K -B法药敏试验中准确取量菌液与用棉拭子蘸取菌液的药敏结果比较。方法 :无菌刻度吸管取0 35ml菌液 ,用L型玻棒均匀涂布 ,同时用棉签蘸取菌液涂布 ,进行K -B法药敏试验。结果 :两种方法的抑菌环直径均在允许范围内 ,准确取菌液量法抑菌环直径分布范围更窄 ,重复性更好。结论 :规范K -B法药敏试验中接种的菌量 。

好氧型甲烷氧化菌对风流中甲烷的降解实验

为了研究好氧型甲烷氧化菌对风流中甲烷的降解效能,分离纯化出可以甲烷为唯一碳源的好氧型耗甲烷菌株,设计出一种模拟巷道风流中甲烷降解实验装置,实现了对不同甲烷浓度、不同风流量、不同菌液体积的调控。实验结果表明:在保持风流量为200 m L/min、菌液体积为200 m L的条件下,甲烷浓度越高,越有利于甲烷的降解;在菌液体积为200 m L、甲烷浓度为50%的条件下,风流量从400 m L/min减到200 m L/min,最低甲烷浓度由42%下降到33%;在保持风流量为200 m L/min、甲烷浓度为30%的条件下,菌液量越多,越有利于甲烷的降解。

A型魏氏梭状芽胞杆菌灭活苗的研究

南京药械厂生物制品研究所杨瑛等同志,将自典型猝死症病猪分离的A型魏氏梭状芽胞杆菌XP5株菌种0.2ml接种于5ml厌氧肉汤试管中,45℃培养1小时,再将试管菌液接种于500ml厌氧肉肝汤中,37℃培养5小时,然后将上述菌液接种于10000ml厌氧肉肝汤中,35℃培养6—8小时,进行菌液的纯检,毒力及菌数测定。按菌液量0.8％用福尔马林灭活,加入适量氢氧化铝胶,制成灭活苗。

胞苷酸生产废水特种微生物筛选及处理效果研究

胞苷酸生产废水具有酸性强、有机物含量高、生物降解难等特点。本试验从胞苷酸生产废水中原位筛选一株特种微生物,经鉴定为绿脓杆菌(Pseudomonas sp.),研究其最佳生长条件。结果表明,绿脓杆菌最适宜的生长条件是pH值为7、生长温度为30℃、振荡培养箱转速为0r/min。在最佳生长条件下探讨菌株投加量对胞苷酸生产废水的影响,绿脓杆菌菌液投加量为100%(v/v)时,反应72h,化学需氧量(ChemicalOxygenDemand,COD)降解率最高,为45.3%。

特种微生物处理叶酸生产废水条件优化

工业生产叶酸不仅需要耗费大量的水,且在生产过程中也会产生大量有机物浓度高、盐浓度高、色度高、可生化性很差的废水。嗜酸耐盐特种微生物对叶酸生产废水的生物降解有重要影响。本实验从叶酸生产废水中筛选出特种微生物,经鉴定为大观贝氏菌(Byssochlamys spectabilis),绘制其生长曲线,考察特种微生物菌液投加量对废水的降解效果。结果表明,大观贝氏菌菌液投加量为50%(v/v)时,反应4天后,废水化学需氧量(Chemical oxygen demand,COD)和苯胺降解率均达最高,分别为84.90%和83.26%。

Electrochemical response to biomass of bacterial cells of Achromobacter sp. CH-1 growth

A simple and effective method has been developed to reflect the growth of bacteria CH-1via the potential of the solution.The results indicate that during the bacterial cultivation,the biomass increases and the potential of the solution decreases over time.The relationship between biomass and potential of the solution could be expressed by the equation with constants of a and b whichare all related to species,batch,number,and growth environment of bacterial.When the initial pH value is10and the initial biomassis6.55×107cell/mL,the correlated equation of the biomass and the potential of the solution could be divided into two segments.Thegrowth of bacteria CH-1is different under various experimental conditions,but the biomass is directly related to the potential of thesolution regardless of the conditions of different initial pH values and bacteria number.

Effect of Different Bacterial-Feeding Nematode Species on Soil Bacterial Numbers,Activity,and Community Composition

The effects of bacterial-feeding nematodes on bacterial number, activity, and community composition were studied through a microcosm experiment using sterilized soil inoculated with soil bacteria （soil suspension） and with bacteria and three species of bacterial-feeding nematodes （ Cephalobus persegnis, Protorhabditis filiformis, and Caenorhabditis elegans）. Catalyzed reporter deposition-fluorescence in situ hybridization, CO2 evolution, and denaturing gradient gel electrophoresis （DGGE） of PCR ampli- fied 16S rRNA gene fragments were used to investigate bacterial numbers, antivity, and community composition, respectively. Our results showed that bacterial numbers and activity significantly increased in the presence of bacterial-feeding nematodes, which indicated that bacterial-feeding nematodes had a significant positive effect on soil bacteria. The different nematode species had different effects on bacterial numbers and activity. C. persegnis and P. filiformis, isolated from native soil, increased the bacterial number and activity more than C. elegans. The DGGE analysis results showed that dominant bacterial species significantly differed among the treatments, which suggested that bacterial-feeding nematode species modified the bacterial community composition in soil. Further gene sequence analysis results showed that the dominant bacterial species in this study were gram-negative bacteria. Given the completely same conditions except nematode species, the varied selective feeding behavior of different nematode species was the most likely reason for the altered bacterial community composition. Overall, the alteration of bacterial numbers, activity and community composition resulting from the bacterial-feeding nematodes may ult!mately affect soil ecological functioning and processes.