矿油封藏法等三种方法保藏半知菌的效果

菌种的长期保藏对菌类资源的利用具有重要意义,对保藏菌种的要求是:长期存活,使能延续继代;保持菌种原有的生理特性及代谢活动,减少其变异性。保藏的方法很多,本文总结了矿油封藏、麸皮保藏和冷冻真空干燥三种方     

一种保藏小单孢菌的简便方法─滤纸保藏法

用滤纸法保藏７２株小单孢菌在冰箱１０℃无干燥条件下,保藏７年５个月后检查其存活率、抗菌活力,观察其形态特征、培养特征和生化特征。结果表明,所保藏的菌种全部存活,且抗菌活力、生理特征等保持原有菌株的特征水平。我们认为,用滤纸法保藏小单孢菌效果好,方法简便,适用于在临床上、工业生产上和科研中有实用价值的庆大霉素、小诺霉素、西梭霉素、小单孢菌的保藏。     

一种保藏小单孢菌的简便方法─滤纸保藏法

用滤纸法保藏７２株小单孢菌在冰箱１０℃无干燥条件下,保藏７年５个月后检查其存活率、抗菌活力,观察其形态特征、培养特征和生化特征。结果表明,所保藏的菌种全部存活,且抗菌活力、生理特征等保持原有菌株的特征水平。我们认为,用滤纸法保藏小单孢菌效果好,方法简便,适用于在临床上、工业生产上和科研中有实用价值的庆大霉素、小诺霉素、西梭霉素、小单孢菌的保藏。     

保藏担子菌菌丝体的一种新方法

担子菌种类繁多,其中很多种类可以作为食品和药材。近年来对其提取物(如多糖、酶类)的研究与应用非常重视。但在担子菌的研究与应用过程中,遇到了担子菌种(菌丝体)的保藏问题,经使用一般菌类通用的保藏法及真空冷冻干燥法均不易使其长期存活。就目前习惯用的斜面冰箱保藏法或石蜡油法,也有不同     

微生物菌种保藏方法及关键技术

菌种是国家的重要生物资源,也是生产、教学和科学研究的基本材料。为确保菌种的质量和活力,需要正确的菌种保藏方法。阐述了菌种保藏的重要性、菌种保藏常见方法及其存在的问题,探讨了常用菌种的保藏技术及关键点,好的保藏方法可延长菌种的保存时间,又可防止菌种退化。     

微生物菌种保藏方法及保藏关键技术

菌种是国家的重要生物资源,也是生产、教学和科学研究的基本材料。为确保菌种的质量和活力,需要正确的菌种保藏方法。阐述了菌种保藏的重要性、菌种保藏常见方法及其存在的问题,探讨了常用菌种的保藏技术及关键点,好的保藏方法可延长菌种的保存时间,又可防止菌种退化。     

几种真姬菇菌种保藏方法的保藏效果对比

【背景】菌种保藏方法与保藏效果是菌种质量的前提和保证。随着真姬菇Hypsizygus marmoreus栽培规模和产量的逐年递增,选择最佳的菌种保藏方法也越来越迫切。【目的】对真姬菇菌种的常见保藏方法及保藏效果进行分析和研究,寻找简便、高效、廉价的真姬菇菌种保藏方法。【方法】通过对比菌丝生长率、菌丝脱氢酶活性以及菌丝对色度培养基的脱色率等指标参数来评价保藏方法的保藏效果。【结果】通过对三大类27种真姬菇菌种保藏方法 3个月保藏效果的对比分析发现,三大类菌种保藏方法中保藏效果最好的是水溶液保藏法,其中以0.1%PEG6000水溶液保藏效果最佳;其次为木屑保藏法,其中以盐水浸泡过的杨木木屑保藏效果最好;斜面保藏法效果最差。正常保藏实验的效果好于加速保藏实验。【结论】与当前真姬菇菌种保藏的常规方法相对比,本实验所采用的菌种保藏方法大大拓宽了菌种保藏方法的种类与范围,提高了菌种保藏的效果。     

8种不同方法保藏病原菌效果的对比观察

采用８种不同的菌种保藏方法,对１８种常见病原菌的保藏时间及生物学特性的影响进行了对比观察。结果表明：冷冻干燥法保藏菌种时间最长（本实验室已保存１５年）;肉浸汤琼脂平板法保藏菌种时间最短（２～３月）。保藏时间由长到短依次为：冷冻干燥法＞半固体冷冻法≥半固体斜面加液体石蜡覆盖法＞半固体斜面法＞肉浸汤加液体石蜡覆盖法＞血琼脂平板法＞肉浸汤法＞肉浸汤琼脂平板法。且相同方法对不同菌种保藏时间不同。保藏时间在１年以内的菌种,其生物学特性无明显变异;而经冷冻干燥法保藏时间较长的白喉棒状杆菌、金黄色葡萄球菌、甲型副伤寒沙     

中国一新记录属-加氏菌属

从辽宁省鞍山市采集的玉米罹病籽粒上分离得到甜菜加氏菌Gabarnaudia betae。加氏菌属Gabarnaudia为我国新记录属。本文对其培养形态特征进行了描述,菌种保藏在大连民族学院真菌菌种保藏中心(菌株号IBE000935)。     

辽宁省微生物菌种保藏中心

<正>简介辽宁省微生物菌种保藏中心是2005年经辽宁省科技厅批准、依托辽宁省微生物科学研究,院组建的东北三省唯一的微生物菌种专业保藏管理机构,主要从事微生物菌种资源分离、收集、鉴定、评价,优良菌种选育、保藏、供应及对外交流开展微生物菌种保藏与应用技术研究。本中心拥有完备的菌种保藏管理设施,拥有可容纳50000株菌种的低温保藏库和可保藏     

几种主要食用菌的遗传转化研究进展

对平菇、香菇、草菇、银耳、双孢蘑菇的遗传转化体系的构建及其应用的研究进展进行了综述,对存在的问题进行了分析,并对未来的发展前景进行了展望。     

Selection and study of potent lactose-fermenting yeasts

Whey-fermenting Kluyveromyces cultures were revealed among 105 yeast strains assimilating lactose. Eighteen most potent strains isolated from milk products fermented galactose, sucrose, and raffinose, in addition to lactose. Many yeast strains fermented inulin. Most strains were resistant to cycloheximide and grew in medium containing glucose, NaCl, and ethanol at concentrations of up to 50, 11-12, and 10-12%, respectively (4 degrees C). Three strains had mycocinogenic activity. After fermentation of whey with selected yeast strains at 30 degrees C for 2-3 days, ethanol concentration was 4-5%.     

Optimization of tannase biosynthesis by a newly isolated Rhizopus oryzae

A strain isolated locally and identified as Rhizopus oryzae (RO, IIT KGP) was found to synthesise an extracellular enzyme, tanin acyl hydrolase, showing its degradability of tannic acid to gallic acid. For maximizing the enzyme secretion in the fermented broth, the influencing parameters were optimized in shake flask culture. Experiments showed that modified Czapek dox medium with 2% tannic acid, 1% glucose, 0.05% sodium nitrate incubated for 4 days with 2 days old inoculum was the optimum for the synthesis of tannase by Rhizopus oryzae (RO, IIT KGP). Maximum enzyme activity was found to be 6.12 U/ml.     

汉逊酵母属的两个新种

从中国宣威火腿中分离到两株典型的火腿酵母.它们是火腿微生物菌群的最优势种,可独立、成功地完成火腿发酵全过程,从而避免霉菌及其毒素对火腿的污染.经鉴定,这两株菌均为汉逊酵母属(Hansenula H.et P.Sydow)中的新种,分别命名为宣威汉逊酵母(Hansenula xuanweiensis Jiang sp.nov.)和中国汉逊酵母(Hansenula sinensis Jiang sp.nov.).     

Selection and Study of Potent Lactose-Fermenting Yeasts

Whey-fermenting Kluyveromyces cultures were revealed among 105 yeast strains assimilating lactose. Eighteen strains from milk products, showing maximum potency, fermented galactose, sucrose, and raffinose, in addition to lactose. Many yeast strains fermented inulin. Most strains were resistant to cycloheximide and grew in medium containing glucose, NaCl, and ethanol at concentrations of up to 50, 11–12, and 10–12%, respectively (4°C). Three strains had mycocinogenic activity. After fermentation of whey with selected yeast strains at 30°C for 2–3 days, the ethanol concentration was 4–5%.     

Studies on the Biology of Macrofungi with Reference to their Cultivation

Nutrition, pH, temperature, moisture, light, and aeration as factors influencing mycelial growth, primordia formation, and development of sporophores of 25 species of basidiomycetous macrofungi were studied, of which 18 species produced normal or nearly normal fruit-bodies in the laboratory. It was found that various agricultural by-products and farm wastes, such as sawdust, wood shavings, fallen leaves, soybean hay, bean pods, corn culms, paddy straw, rice glumes, wild grasses, etc. enriched with 20%–25% by weight of rice or wheatbran, made suitable substrata for most of the lignicolous species investigated with the exception of Tremella fuciformis and Lentinus edodes, and that well fermented dungs of domestic animals, such as horse, cow, pig, sheep, rabbit, and poultry, appeared to be satisfactory substitutes for bran as accelerators for fructification. Yields of carpophores were more or less directly proportional to the percentages of accelerators added to the substratum. The vegetative growth of the majority of species studied took place over a wide pH range of 3.0–8.0, with the optimum at 5–6, while the optimal pH for Ganoderma lucidum, Lentinus edodes, and Hericium erinaceus being about 4.0 and the maximum pH limit for H. erinaceus only 5.4. In Auricularia hispida, the pH range for fructification and that for mycelial growth were almost the same, but in Collybia velutipes and Agaricus bitorquis the pH range for sporogenesis was much more restricted, the optimal being 5–6 and 7–8 respectively. Most of the species investigated produced mycelium within a temperature range of 6–36℃, the optimum being about 24–27℃. However, the optimal temperatures for Auricularia auricula, Poria cocos and Volvariella volvacea var. heimii were found to be 30℃ or more. The temperatures required for sporophore and for primordia formation varied from species to species. While the fruit-bodies of Lentinus edodes and Pleurotus sapidus appeared only after "chilling", temperature fluctuations did not exert any stimu- lating effect on primordia differentiation in some other species. Using the temperature requirement for the initiation of primordia as the criterion, the species studied were grouped into the following categories: (1) high-temperature species, such as Ganoderma lucidum, Pleurotus rhodophyllus, Collybia radicata, Volvariella bombycina, and Volvariella volvacea var. heimii, with their optimum and maximum tem- peratures for primordia initiation exceeding 24℃ and 30℃ respectively; (2) intermediate species, such as Auricularia auricula, Tremella fuciformis, Pleurotus citrinopileatus, Pholiota adiposa, Agaricus bitorquis, and Agaricus rubellus, with their maxima not exceeding 28 ℃ and with the optimum lying within 20–24 ℃; and (3) low-temperature species, such as Auricularia hispida, Hericium erinaceus, H. caput-medusae, Pleurotus sapidus, Lentinus edodes, Collybia velutipes, and Agaricus bisporus, with their maxima not exceeding 24 ℃ and with the optimum under 20 ℃. Thus, under natural climatic conditions of a given region, without artificial heating or cooling, it was deemed practicable to arrange, according to the temperature response of the various species, a series of mushroom crops to be grown in rotation the year round. Moisture was found to have considerable influence on vegetative growth as well as reproduction. Most of the lignicolous species grew well on the sawdust medium, which contained 100%–340% by weight of water. Moisture content between 260%–340% was more favourable for fruiting, and several flushes were secured. At 100% moisture, fruiting was considerably delayed and only one flush of poorly developed carpophores was obtained. Aeration also played an important role in basidiocarp development. Stagnant humid air or CO2-laden atmosphere markedly inhibited pileus development, diminishing the size of pilei and causing morphological abnormalities. Adequate supply of fresh air with 80%–90% relative humidity tended to maintain a normal rate of transpiration, thereby guaranteeing a flourishing crop. In some species, such as Ganoderma lucidum, Tremella fuciformis, Pleurotus sapidus, Pleurotus citrinopileatus, Volvariella bombycina, Hericium erinaceus, Auricularia hispida, Armillaria mucida, and Lentinus edodes, light was found to be absolutely necessary. In these species, primordia formation would not commence until exposed to light. Certain other species, such as Auricularia auricula, Pleurotus rhodophyllus, Collybia velutipes, Pholiota adiposa, and Agaricus bitorquis, were able to fructify in total darkness, though their primordia formation was promoted by light. For the normal development and pig- mentation of fruit-bodies, light appeared to be essential. Morphological abnormalities, such as long slender stipes and thin rudimentary pilei occurred in total darkness. Results of experiments indicated that in most of the species studied, light reduced mycelial growth. The inhibitory effect was mainly due to the blue region (380–540 mμ) of the visible spectrum rather than the red region (570–920 mμ). On the contrary, light at the blue end was shown to be most effective and even essential for fructification; the red end being similar to darkness, evoked almost no response. Having analyzed the results obtained, it seems reasonable to assume that the ontogeny of higher Basidiomycetes consists most probably of four developmental stages, viz., (1) the stage of vegetative growth, (2) the stage of primordia initiation, (3) the stage of sporophore development, and (4) the stage of basidiospore formation, each of which has its own physiological characteristics and metabolic speciality.Hence the requirements of the various stages differ considerably.     

Changes in biological production of the cyanobacterium, Nostoc sp. strain MAC, under subinhibitory concentrations of tannic acid and related compounds

The effects of gallic acid, methyl gallate, propyl gallate and tannic acid on cell growth, protein synthesis, photosynthesis, membrane function and metabolic activity of Nostoc sp. strain MAC were quantitatively investigated. Treatment of MAC with 1/2 inhibitory concentrations of tannic acid and related compounds resulted in a severe decline in biological production. Chlorophyll a and c-phycocyanin syntheses were inhibited by over 90%. Glutamine synthetase and nitrate reductase activities were suppressed by at least 45% and 56%, respectively. The percentage inhibition of total cell yield was around 40%, whereas that of total protein was around 80%. In addition, cellular potassium loss was 2–5 times that of control cultures and was accompanied by a loss in phosphate of about 1.2 times that of control cultures. However, gallic acid did not inhibit c-phycocyanin synthesis, nor did tannic acid or propyl gallate inhibit the activity of glutamine synthetase. Methyl gallate had no effect on electrolyte efflux. The control of biomass accumulation in relation to the production of off-flavor compounds in cyanobacteria by natural tannin compounds may have important aquacultural implications. This revised version was published online in June 2006 with corrections to the Cover Date.     

Molecular diversity of tannic acid degrading bacteria isolated from tannery soil

AIMS: The aim of this study was to enrich and isolate bacteria from a tannery soil that were capable of utilizing tannic acid and gallic acid as sole source of carbon aerobically, and to characterize their diversity in order to identify efficient strains that can be used for tannin bioremediation. METHODS AND RESULTS: Bacterial strains were isolated after enrichment in minimal medium with tannic acid or gallic acid as sole carbon source. Polymerase chain reaction (PCR) restricted fragment length polymorphism of 16S rDNA [amplified ribosomal DNA restriction analysis (ARDRA)] and BOX-PCR was used to characterize their diversity. Two strains showing relatively high efficiency in degrading tannic acid and gallic acid were identified on the basis of carbon source utilization pattern (BIOLOG) and 16S rDNA sequence. CONCLUSIONS: Bacterial strains capable of degrading tannic acid and gallic acid could be grouped into six and seven clusters on the basis of ARDRA and BOX-PCR, respectively. On the basis of 16S rDNA sequence, the most efficient isolate degrading tannic acid belonged to Pseudomonas citronellolis, whereas the most efficient gallic acid degrader showed maximum phylogenetic relatedness to P. plecoglossicida. SIGNIFICANCE AND IMPACT OF THE STUDY: Aerobic tannic acid degraders such as the two strains isolated in this study can be used for tannin bioremediation, and in the study of genes involved in the production of tannase, an industrially important enzyme.     

从白腐菌中筛选漆酶高产菌株的初步研究

从中国分离的149株木腐菌中,有30株具有漆酶活性。在添加了阿魏酸的液体培养基中,漆酶产量高(每升培养液中漆酶含量在10000单位以上)的菌株有9个:游离细胞培养的彩绒革盖菌Coriolus versicolor G30,相邻小孔菌Microporus affinis G07,血红密孔菌Pycnoporus sanguineus W006,W006-2,W3008,G05和香菇Lentinus edodes G18,以及固定细胞培养的鲑贝革盖菌Coriolus consors 98563和干酪菌Tyromyces sp. 98420。彩绒革盖菌、相邻小孔菌和血红密孔菌具有重要的生物工程研究价值。     

利用黑曲霉单宁酶酶法制取没食子酸的研究

利用已有的 10株高单宁酶活性的菌株为起始菌 ,经活化分离选择 ,借助Ⅱ级发酵培养程序、生物转化、结合TLC分析进行筛选实验。最后选出具有高单宁酶活性的 1号和 5 0号菌株 ,开展了没食子酸 (GA)克量级生物转化法制备实验 ,结果表明 ,本酶法工艺是可行的 ,在发酵液中GA的浓度分别达到2 0 .6mg/ml和 2 1 3mg/ml,产品产率 (以从五倍子提取的单宁酸计 )达到 41 2 %和 42 6 % ,具有潜在的工业开发价值