绿色产色链霉菌E-219菌落的形态分化

菌株E-219由原始菌株CGMCC4.1119经60Coγ诱变及原生质体融合等手段改造后所得,本文通过分子荧光探针、荧光显微镜和电镜对绿色产色链霉菌E-219在固体基质表面的发育分化周期、斜面培养时间对阿维拉霉素产量的影响进行了研究,以为工业发酵选择适当的斜面种子提供理论依据。试验表明该菌株菌落发育过程伴有间断性菌丝凋亡,分生孢子的产生是活性菌丝分化的结果。与原始菌株相比该菌落形态呈现显著不同,其孢子萌发形成杂色初生菌丝,基内菌丝出现二次死亡(48h)及其中活性菌丝片段的二次快速生长,分生孢子形成数量多。原始菌株呈螺旋状孢子丝,孢子表面带刺,而E-219为直线型孢子丝,分生孢子表面光滑无刺突。摇瓶试验表明,菌种斜面种龄以106h左右为宜,此时分生孢子活性高,阿维拉霉素发酵单位可达1200mg/L。     

~(60)Coγ射线诱变阿维拉霉素筛选高产菌株及培养基优化

用60Coγ射线对绿色产色链霉菌A-05菌株进行了诱变处理,以正突变率为标准确定诱变的适宜剂量为350 Gy。诱变后得到5株较高产突变菌株,其中H-15菌株经连续传代6次,遗传性状稳定,阿维拉霉素发酵单位达到68.5mg/L。采用响应面分析法对菌株H-15生产阿维拉霉素的发酵培养基碳氮源进行了优化设计。在所试验的碳氮源中,可溶性淀粉、核糖分别作为唯一碳源时,阿维拉霉素发酵单位较高,分别达82.67和79.45mg/L,乳糖、果糖、葡萄糖分别作为唯一碳源时菌株的效价较低;3%的豆粕粉和2%的大豆蛋白胨作为氮源时阿维拉霉素发酵单位分别为77.6和62.7mg/L。采用双碳源双氮源更有利于菌株提高阿维拉霉素的发酵单位,响应面分析结果表明,可溶性淀粉、核糖和大豆蛋白胨对阿维拉霉素发酵单位影响较显著。优化后的碳氮源组成为:可溶性淀粉20.12g/L,D-核糖7.81g/L,豆粕粉25.23g/L,大豆蛋白胨5.06g/L。优化后的模型计算出阿维拉霉素发酵单位由原来的71.63mg/L提高到101.48mg/L。     

桔青霉形态分化与核酸酶P1产量突变关系研究

桔青霉（Penicillium citrinum）CICC 4011菌株经60Coγ射线诱变以及多菌株连续多轮原生质体融合后,变异株产核酸酶P1能力与形态性状出现了较大差异。研究表明黄绿色或灰绿色菌落产酶水平较高,绿色或艾绿色菌株产酶水平较低。选择不同产色特征的变异株（J1Y6、 F-13、F-R-33）与CICC 4011进行比较,表明4株桔青霉生长速度没有明显差异。融合子F-R-33菌落呈深艾绿色,产水溶性红色素,核酸酶P1低产（23.1U/ml）;诱变菌株J1Y6菌落呈黄绿色,产水溶性黄绿色素,核酸酶活较高（167.3U/ml）;融合子F-13菌落呈灰绿色,不产水溶性色素,核酸酶活较高（578.6U/ml）。电镜观察发现J1Y6、F-13分生孢子梗上帚状分枝减少,菌丝生长粗壮,产孢能力不及4011及F-R-33。核酸酶P1和色素虽然都是次级代谢产物,但核酸酶P1的合成明显与生长相关,而色素的合成则表现出非相关性。突变株RAPD-DNA多态性检测率为70%。UPGMA聚类分析,菌株F-R-33与出发菌株4011聚为一类（相似系数0.9）,核酸酶P1高产菌株J1Y6和F-13聚为一类,高产与低产突变株的DNA多态性表现出明显差异（相似系数0.8）。     

不利用香菇多糖的香菇单核菌株的选育

以香菇939菌株的担孢子为材料,应用紫外线诱变得到1株不能利用香菇多糖的突变株939-5,其菌落形态和生长速度与未突变H型单核菌株相同,多糖产量比未突变H型单核菌株提高30.7%,比双核菌株提高19.6%。该菌株产香菇多糖的最适碳源是淀粉,氮源为酵母膏,培养基初始pH值为6.0;Mg2+ 对其产香菇多糖有显著的促进作用;高溶氧水平则对产香菇多糖有明显的抑制作用。这些产香菇多糖的特性与已报道的香菇939菌株的S1型单核菌株相同。     

辐照木霉菌株的生物学效应研究

本文研究了6 0 Coγ射线辐照木霉 (Trichodermaspp)菌株的诱变效果。结果表明 :在γ射线的作用下 ,木霉分生孢子萌发率显著降低 ,孢子萌发时间加长 ,部分萌发孢子菌丝生长畸形 ;随着照射剂量的增加 ,木霉孢子存活率急剧下降 ,剂量效应曲线符合一次击中模型S =e-λD;诱变效应方程为 :Y =-0 940e1 2 9x,r=0 953 3 (r0 0 1=0 765)。依各菌株对生长速度、产孢量、开始产孢时间、菌落颜色等变异情况 ,初筛得到变异菌株 1 3 0株。     

白僵菌抗多菌灵突变株的诱变及生物学特性研究

采用菌丝生长速率法测定了球孢白僵菌对多菌灵的敏感性和最低完全抑制浓度(MIC)。结果显示,在供试的球孢白僵菌菌株中,Bb06菌株对多菌灵最敏感,其EC₅₀值为1.0688μg/ml,多菌灵对球孢白僵菌菌丝生长的MIC为9μg/ml。通过菌丝块诱变法和分生孢子诱变法获得球孢白僵菌抗多菌灵突变株,并测定球孢白僵菌不同抗性突变株对多菌灵的抗性水平。结果表明,在抗性突变株中,BC-4菌株的EC₅₀值最大,为258.7711,对多菌灵的抗性水平最高,达到242.11;BC-3菌株的EC₅₀值最小,为18.6311,抗性水平最低。同时对球孢白僵菌抗多菌灵突变株的菌丝生长速率和产孢能力差异的研究表明,Bb06菌株(亲本菌株)的生长速率最大,为1.78mm/d,BC-8菌株的生长速率最小,为1.41mm/d。球孢白僵菌不同抗性突变株的产孢能力均比对照敏感菌株强,但不同菌株间存在一定差异,在抗性突变株中,BC-4菌株的分生孢子产生量最大。     

航天搭载淡紫拟青霉的生物学效应

为探讨航天诱变对淡紫拟青霉的生物学效应的影响,利用淡紫拟青霉山东菌株搭载"神舟八号"宇宙飞船进行诱变处理。对筛选得到的30个淡紫拟青霉航天诱变菌株进行了形态、色素、菌丝及孢子形态、菌落生长速度、菌丝干重和产孢量等生物学检测,并测定了各诱变菌株对南方根结线虫卵和松材线虫卵的寄生率。结果表明,淡紫拟青霉航天诱变菌株各项生物学特性与原始菌株存在分化。航天诱变后的菌株菌落形态、色素和菌丝结构与原始菌株差异明显;菌落生长速度、菌丝干重和产孢量的负突变率均高于正突变率;菌株对松材线虫卵的致病力较低,寄生率最高的菌株Sd-m-20的寄生率仅为18.0%,菌株对根结线虫卵致病力较高,菌株Sd-m-9,Sd-m-11,Sd-m-16,Sd-m-22和Sd-m-26对根结线虫卵的寄生率分别提高了14.48%、14.90%、12.35%、7.66%和17.45%,显著高于原始菌株的寄生率(78.3%)。航天处理对淡紫拟青霉诱变效果显著,其优良突变菌株可能用于淡紫拟青霉对南方根结线虫的生物防治。     

厚垣普可尼亚菌航天诱变的生物学效应

为探讨厚垣普可尼亚菌航天诱变的生物学效应,对筛选得到的29个厚垣普可尼亚菌航天诱变菌株进行形态、色素、孢子形态、菌落生长速度、菌丝干重、产孢量和致病力等生物学特性检测,并测定各航天诱变菌株的耐盐性以及对苯菌灵的抗性。结果表明,厚垣普可尼亚菌航天诱变菌株各项生物学特性与原始菌株存在差异。航天诱变后的菌株菌落形态和色素与原始菌株差异明显;菌落生长速度和菌丝干重的负突变率均高于正突变率;产孢量的正突变率高于负突变率;菌株Pc-m-4、Pc-m-6、Pc-m-10、Pcm-15和Pc-m-123对南方根结线虫卵的寄生率分别为92.33%、93.67%、91.67%、90.67%和90.33%,显著高于原始菌株的寄生率(81.00%),其中,菌株Pc-m-6具有较好的苯菌灵抗性,菌株Pc-m-10对盐具有较好的耐受性。航天诱变处理对厚垣普可尼亚菌影响显著,其诱变后的优良菌株具有防治南方根结线虫的潜力。     

原生质体EMS诱变选育杏鲍菇高产菌丝多糖菌株

为了促进杏鲍菇的产品研发,利用甲基磺酸乙酯(EMS)诱变处理杏鲍菇PL7菌株原生质体,筛选菌丝多糖含量显著增加的原生质体诱变菌株。结果表明,EMS诱变原生质体的适宜浓度和处理时间分别为0.20%和15 min;从160个原生质体再生菌株中筛选出与亲本菌株拮抗作用明显的22株诱变株;通过菌丝多糖浓度测定,获得菌丝多糖浓度显著增加的7株诱变菌株;通过菌落生长速度测定、RepPCR分析和出菇试验,最终获得高产菌丝多糖的新型菌株D3-12。本研究结果为杏鲍菇种质资源创新和新品种选育提供了新途径。     

禾长蠕孢菌的紫外诱变改良和除草活性评价

为进一步提高稗草生防潜力菌禾长蠕孢菌(Helminthosporium gramineum Rabenh f.sp.echinochloae,HGE)的杀草活性,采用紫外诱变的方法对该菌种进行改良,经筛选获得1株适合液体发酵的突变菌株M1。与出发菌株HGE菌落墨绿色相比,突变株M1菌落呈灰白色至白色,表现出明显差异,并且M1生长速度快,其发酵液对稗草(Echinochloa crusgalli(L.)Beauv)根芽的抑制效果均优于出发菌株HGE。连续7次传代培养发现M1仍具有良好的遗传稳定性。采用RAPD-PCR方法对出发菌株和突变菌株M1同时进行PCR扩增,结果表明,突变菌株的遗传物质已经发生了改变。同时对其液体发酵工艺进行了研究,初步确定了最佳发酵工艺。所用培养基马铃薯200gL,葡萄糖30gL,麸皮20gL,酵母膏1gL,KH2PO42gL,MgSO4·7H2O1gL,初始pH7,发酵温度24℃和150rmin振荡培养6d的发酵方案,突变菌株M1菌丝体产量最高,达14.37gL。液体培养获得毒素的最佳发酵工艺为培养基蔗糖30gL,(NH4))2C4H4O65gL,NH4NO31gL,酵母膏1gL,KH2PO41gL,MgSO4·7H2O0.5gL,NaCl0.1gL,CaCl20.1gL,水解酪蛋白0.5gL;初始pH7.25,发酵温度为24℃和静置培养14d。     

Accumulation and localization of cesium in edible mushroom (Pleurotus ostreatus) mycelia

The characteristics of Cs accumulation and localization in edible mushrooms were examined using the mycelia of Pleurotus ostreatus-Y1. Scanning electron microscope images revealed the existence of white spots, and energy dispersive X-ray microanalyzer analysis indicated the presence of larger amounts of Cs and P in these spots in mycelia cultured on medium containing 25 mM CsCl. The (137)Cs activities in the mycelia were approximately 4-6 times higher than those in water used for (137)Cs elution. Higher Cs concentrations in the sediment fraction including vacuolar pellets were obtained compared to the upper fractions. It was observed that yellowish spots caused by the fluorescence of 4',6-diamidino-2-phenylindole (DAPI)-stained polyphosphate were localized in the mycelia. The higher fluorescence intensity of the yellowish-grained spots was measured in comparison with other regions in the mycelium. These results suggested that Cs in the mycelia was trapped by polyphosphate in vacuoles or other organelles.     

Mutabilis in mutabili: Spatiotemporal dynamics of a truffle colony in soil

The functioning of ectomycorrhizal (ECM) symbioses is closely related to the development of the soil mycelial phase the ECM fungi. The properties and spatiotemporal dynamics of such mycelia in ecosystems is, however, poorly understood. Here we show, using a soil colony of summer truffle (Tuber aestivum) as a model, that an ECM mycelium may only grow and colonize newly-opened soil patches when soil temperatures rise above certain threshold, in this case +10 °C, provided other requirements such as sufficient soil moisture are fulfilled. Extension rates of truffle mycelium in the fields was recorded as >0.3 μm min⁻¹, several-fold greater than that predicted from laboratory cultures. Further, we demonstrated that there was a consistent spatial differentiation in mycelium growth patterns within the fungal colony on a decimeter scale, changing from “diffusion” type of growth at the colony margin to “colony-front” pattern further away from the colony margin. This change was clearly accompanied by shifting structure of soil microbial communities with Terrimonas sp. and another unidentified bacterium correlating with the “colony-front” mycelium growth pattern, and Sphingomonas sp. and Lysobacter brunnescens with the “diffusion” type of mycelium growth. Possible implications of the observed truffle colony differentiation are discussed for processes like fruit-body formation and dispersal of this ECM fungus. Our data indicate that the thallus of T. aestivum has to be considered as a principally variable (“mutabilis”) being in space and time, whose behavior correlates with conditions in ever changing soil environment (“in mutabili”).     

禾长蠕孢菌菌种的紫外诱变改良和除草活性评价

为进一步提高稗草生防潜力菌HGE的杀草活性，本文采用紫外诱变的方法对该菌种进行改良，经筛选获得一株适合液体发酵的突变菌株M1。与出发菌株HGE菌落为墨绿色相比，突变株M1菌落呈灰白色至白色，表现出明显差异，并且M1生长速度快，其发酵液对稗草根芽的抑制效果均优于出发菌株HGE。连续7次传代培养发现M1仍具有良好的遗传稳定性。采用RAPD-PCR方法对出发菌株和突变菌株M1同时进行PCR扩增，结果表明突变菌株的遗传物质已经发生了改变。同时对其液体发酵工艺进行了研究，初步确定了最佳发酵工艺。采用3号培养基，初始pH值为7，发酵温度为24℃，150r/min振荡培养6d的发酵方案，突变菌株M1菌丝体产量最高，达14.37g/L。液体培养获得毒素的最佳发酵工艺为：4号培养基，初始pH值为7，发酵温度为26℃，静置培养14d。     

THE ECOLOGY AND PHYSIOLOGY OF SOIL FUNGI INVOLVED IN THE DEGRADATION OF LIGNIN AND RELATED AROMATIC COMPOUNDS

A study has been made of the colonization by soil fungi of kaolin pellets in which was incorporated either a lignin preparation extracted from Phragmites or the lignin-related substances, vanillic acid or α-conidendrol. Fungi isolated from the lignin pellets by the dilution method were grown in liquid culture containing the Phragmites lignin. Subsequent analysis by UV absorption spectrometry indicated up to 40 per cent loss of this material. IR analysis of the residual lignin showed that it was little altered. Fungi from the pellets containing vanillic acid and α-conidendrol were isolated by direct transfer of spores and mycelium from the pellets to agar plates. The range of soil fungi already known to metabolize vanillic acid in pure culture was extended by this method and included Stilbum spp., Humicola sp., and two unidentified species. Dry-weight determinations of mycelia combined with UV absorption spectrometry and paper chromatography of culture filtrates indicated that, with the exception of Acremoniella sp., all isolates metabolized vanillic acid when it was supplied as sole C source. Growth-promoting substances present in yeast extract were required by Volutella spp. before the vanillic acid was metabolized. The pellet technique offers many possibilities for studying the microbiological degradation of soil substances and in addition enables the soil micro-habitats to be explored in greater detail than has previously been possible.     

离子注入对苹果酒酵母菌的影响

以野生型苹果酒酵母菌Y0 2 为出发菌株 ,利用 8× 1 0 15ion cm2 注入剂量对出发菌株Y0 2 进行诱变处理 ,得到 1株形态特征、部分生化特征、菌体蛋白质等发生明显变异的突变株IONⅡ 1 1dry ,该突变株的产酒率比出发菌株提高 2 2 4% ,表明离子注入诱变育种是行之有效的     

柱塞式平模生物质成型机设计与试验

针对传统生物质平模成型机能耗高、磨损严重的问题,该文提出了一种柱塞式平模生物质致密成型方法,并设计了成型机样机。该样机通过斜盘与弹簧配合,驱动柱塞往复运动,柱塞在运动过程中仅对模具内的原料进行挤压。成型模具部分采用组合式设计,主要由平模与成型套筒组成,可在成型套筒外部加热,同时可更换长径比不同的成型套筒以适应不同生物质原料。该文以不同颗粒度玉米秸秆和刺槐为原料,在原料含水率为15%,斜盘转速为50 r/min,原料温度为室温的条件下进行了试验,结果表明柱塞式平模生物质成型方法可行,颗粒成型率均高于98%,成型密度大于1.1 g/cm3,机械耐久性高于97%。该文提出的成型方法为生物质致密成型技术提供参考。