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631.
632.
Anaerobic microbial associations have been isolated that degrade aminoaromatic acids to methane and carbon dioxide at high rates. Significant differences between the morphological, cytological, and physiological traits of cultures isolated from samples of adapted and unadapted sludge are shown. The effects of cultivation temperature, illumination, and presence of mineral nitrogen and bicarbonate in the medium upon adaptation of enrichment cultures to substrates and subsequent behavior of the anaerobic associations have been studied. Intermediate and final products of degradation of aminoaromatic compounds and the sequence of their formation in the cultures have been determined. We have also studied the effects of exogenous electron acceptors and additional carbon sources on the degradation of aminoaromatic compounds.__________Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 4, 2005, pp. 422–428.Original Russian Text Copyright © 2005 by Kotova, Savel’eva, D’yakonova, Sklyar, Kalyuzhnyi, Stams, Netrusov.  相似文献   
633.
634.
On the basis of hydrocarbon-oxidizing strain Phyllobacterium myrsinacearum DKS-1 isolated from shelf waters of the North Caspian Sea, the bioagent Phyloil in the liquid and in dry form on a carrier is developed. The tests of a bioagent application have shown the efficiency of its application for cleaning of seawater from oil hydrocarbons, including polycyclic aromatic ones.  相似文献   
635.
Microorganisms growing on a mineral medium with crude oil and its light fractions as the only source of carbon and energy have been isolated from samples of oil-polluted soils collected in the Usa district (Komi Republic, Russia). Hydrocarbon-oxidizing psychroactive bacteria of the genus Cytophaga, which are clearly capable of consuming crude oil hydrocarbons, have been identified for the first time. A method for cultivating microorganisms on porous plastic is proposed.  相似文献   
636.
陕北黄土区雨季后山地枣林土壤水分动态变化研究   总被引:1,自引:0,他引:1  
选取陕北延川县齐家山红枣试验基地枣林地、苹果林地和撂荒草地为研究对象进行土壤水分动态变化研究,结果表明:①不同坡位、不同坡向和不同整地方式的枣林地土壤水分存在显著差异;其中,研究区下坡位土壤水分最高,为14.19%;阴坡土壤水分最高,为14.19%;水平阶整地枣林土壤水分显著高于原状坡。②研究区不同植被类型间土壤水分垂直变化趋势基本一致。枣林地土壤水分最高,为11.49%;不同植被类型0~100 cm土壤贮水量依次表现为枣林地(144.76 mm) > 苹果林地(124.19 mm) > 撂荒草地(72.20 mm)。③不同植被类型土壤贮水亏缺度存在差异。雨季前,0~20 cm土层亏缺度最小,平均亏缺度表现为撂荒草地 > 枣林 > 苹果林;雨季后,土壤水分亏缺度表现为撂荒草地 > 苹果 > 枣林,除枣林地外均高于雨季前土壤水分亏缺度。④雨季后,研究区3种植被类型0~20 cm土层土壤水分亏缺加剧;20~100 cm土层中,枣林土壤贮水补偿度为正值,土壤水分得到补偿,但最高仅为22.95%,枣林土壤水分仍处于亏缺状态并未完全恢复;苹果林地土壤贮水补偿度则为负值,表明土壤水分亏缺进一步加剧;撂荒草地土壤水分补偿度基本维持在0左右,土壤水分亏缺没有持续恶化。  相似文献   
637.
Abstract The new planthopper taxon, Garumnella bella gen.n. , sp.n. , from Xizang, China, is described and illustrated, including external morphology of adult and eggs and structures of the male and female genitalia. The new genus is compared with Garumna Melichar and Paragarumna Muir, resulting in Paragarumna ( syn.n. ) being placed as a junior synonym of Garumna, with two new combinations, i.e. Garumna pseudolepida (Muir) comb.n. and Garumna melichari Baker comb.rev. New locality records for Garumna species are given. The morphology of the genitalia and egg of a copulating pair of the new genus is investigated. The female has a ventrally sclerotized posterior vagina forming a torsion groove, an unusual long membranous anterior vagina and an enlarged common oviduct. During copulation both the aedeagus and the torsion groove appear tightly interlocked, which may help to maintain the copulatory position. The aedeagus is observed in the bursa copulatrix.  相似文献   
638.
为明确药用植物委陵菜与其同属植物星毛委陵菜在不同基原之间的代谢差异,更有效的利用药用植物资源。基于气相色谱与质谱联用技术对两药用植物间的小分子初生代谢物进行非靶向代谢组学分析,利用主成分分析和偏最小二乘法分析,寻找可区分两物种的差异代谢物以及在初生代谢途径上的差异。结果:利用GC-MS在两植物中共检测到134个色谱峰,通过与数据库比对,共鉴定出43种初生代谢产物。PCA分析结果显示代谢物在委陵菜和星毛委陵菜间的分布有较大的差异;采用OPLS-DA筛选获得导致2物种区分的差异代谢物共33种,两物种在半乳糖代谢、淀粉和蔗糖代谢、氨酰生物合成、氨基糖和核苷酸糖代谢和果糖和甘露糖代谢途径有显著的差异。委陵菜和星毛委陵菜的初生代谢方面存在较大差异,虽然两植物来源于同科同属植物,但是星毛委陵菜不适合代替委陵菜作为药材使用。  相似文献   
639.
Abstract. Lysozymes are widely distributed in many organisms as one of the components of defence mechanisms. In herbivores, when nitrogen is not contained in sufficient amounts in the diet, bacteria lysed by stomach lysozymes are used as sources of nitrogen. In ruminants, lysozymes function as digestive enzymes in the true stomach. A convergence of amino acid sequence has been shown between the stomach lysozymes of different ruminants, and similar lysozymes have recently been reported in the gut or salivary gland of insects. In this mini review, the enzymatic and ecological functions of lysozymes in insects, particularly in termites, are introduced, together with future studies that are needed in this field.  相似文献   
640.
The viability of lyophilized microorganisms belonging to different physiological groups was determined after 50-year storage at 2–4°C. During this period, the number of viable cells gradually decreased, in some cases, by 2–3 orders of magnitude. However, after 50-year storage, the ampoules contained considerable amounts of viable cells (in many cultures, 106–109 cells) that were quite sufficient for the culture maintenance. All the studied lyophilized microorganisms (pro- and eukaryotes) retained their viability after 50-year storage, a longer period than those known in literature.  相似文献   
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