Enhancement of Arachidonic Acid Production by Mortierella isabellina Through Protoplast Regeneration Mutagenesis

A developed method was used for the enhancement of arachidonic acid production by M. isabellina. An orthogonal, rotatable and central composite design was applied to determine the optimum conditions for protoplast regeneration mutagenesis. The results showed that a commixture enzyme (cellulase and glusulase) at the concentration of 4%, enzymolysis temperature at 30℃ and enzymolysis time on 7.5 h were the optimal conditions, in which the lethality of M. isabellina spores was 78.4%. After mutagenesis and re-s...     

Mortierella wolfii keratomycosis in a horse

Purpose To describe a case of superficial keratomycosis caused by Mortierella wolfii (M. wolfii) in a horse. Methods A thoroughbred filly was presented with painful right eye of 2 days’ duration. A superficial corneal ulcer was observed ventrally together with multifocal punctuate opacities axially. Samples were collected by swabbing and scraping the ulcerated lesion and submitted for microbiologic and cytologic examination. Results Microscopic evaluation of debrided corneal tissue revealed the presence of nonseptate fungal hyphae, and culture of a corneal swab yielded fungal growth. Medical treatment with topical antifungal, antibiotic and autogenous serum and systemic anti‐inflammatory resolved the problem within 2 weeks. Conclusions Cytologic evaluation of a corneal scraping was useful to make a clinical diagnosis of keratomycosis. Based on the mycological characteristics, the fungus isolated from the corneal lesion was identified as M. wolfii. To the authors’ knowledge, this is the first case report of equine keratomycosis associated with this fungus, although the organism is known to infect various organs of cattle.     

虫草发酵菌粉的活性成分分析

[目的]比较虫草头孢和蝙蝠蛾被孢霉2种发酵菌粉中活性组分的差异,为虫草发酵菌种的开发提供数据参考.[方法]采用重量法测定多糖含量,采用离子色谱法检测粗多糖的单糖组成,采用高效液相色谱法测定核苷类物质含量,采用Folin-Ciocalteu法测定总多酚含量,采用香草醛-高氯酸法测定总三萜含量.[结果]2种菌粉中粗多糖含量在7％左右,均由6种单糖构成;发酵菌粉中均检测到含量较高的胞苷、鸟苷和腺苷等核苷类化合物;2种虫草发酵菌粉中总多酚的含量约5 mg/g,三萜物质含量约8 mg/g.[结论]虫草头孢和蝙蝠蛾被孢霉2种发酵菌粉在多糖、核苷、多酚和三萜类物质的含量上无显著差异,均具有较高的药用活性和良好的开发前景.     

3株被孢霉的鉴定及其生物学特性研究

从土壤中分离获得3株被孢霉,对其营养、温度、pH等生物学特性进行研究,结果表明：3个菌株间生物学特性存在显著差异。3个菌株的适宜氮源均为蛋白胨,1、2,3号菌株适宜碳源依次为葡萄糖、淀粉、蔗糖;1号菌株和3号菌株的适宜生长温度均为5℃,2号菌株的适宜生长温度为30℃;3个菌株在pH4—9环境下均能生长,适宜pH为7。由ITSrDNA分子鉴定确定3株菌均为高山被孢霉。     

响应面法优化深黄被孢酶发酵生产花生四烯酸的培养条件

采用响应面法对深黄被孢霉发酵生产花生四烯酸的培养条件进行优化。在单因素试验基础上,利用DesignExpert设计了响应面试验,研究培养时间、培养温度、接种量对花生四烯酸产量的影响。结果表明,最佳的培养条件为培养温度28℃,培养时间为7 d,接种量为20%,在此条件下ARA产量为2.42 g/L,实测结果与响应面拟合所得方程的预测值符合良好。     

Soil Fertility Improvement by Litter Decomposition and Inoculation with the Fungus Mortierella sp. in Avocado Plantations of Colombia

Litter decomposition is a major process in nutrient recycling, despite that few studies have considered this in soil fertility management. The aim of this study was to evaluate the effect of litter decomposition and its inoculation with the fungus Mortierella sp. on soil fertility parameters in Andisols cultivated with avocado cv. Hass. Litterbags containing avocado leaves either uninoculated or inoculated were distributed around the trees. As control litter was not allowed to accumulate on the soil surface. Eighteen months later soil samples were collected just below uninoculated and inoculated litterbags and control sites. Soil pH, potassium, calcium, phosphorus, magnesium, and boron significantly increased with litter and in some sites the increase was higher with inoculation. By contrast, soil aluminum, iron, and manganese were significantly lower in the presence of litter (uninoculated and inoculated), whereas zinc was significantly higher when litter was present.     

温度和糖驯化对高山被孢霉SM96γ-亚麻酸产生的影响

采用不同糖浓度和温度2个因子共同驯化高山被孢霉SM96.通过驯化发现20℃驯化最佳,较高温度驯化结果不稳定,各温度下8%糖驯化绝对产量最高.选出了2个驯化结果较优的菌株：M230、M920.两者的γ-亚麻酸（GLA）产量分别为240 mg/L和303 mg/L,比出发菌株SM96分别增加了108.696% 和92.994%.     

杨梅衰弱病根际土壤真菌的定量检测与分析

 杨梅衰弱病在杨梅主产区发生严重,但其成因尚未明确。为明确根际土壤真菌与衰弱病的相关性,本研究以来自仙居、临海和兰溪3个不同地区的健康植株和衰弱植株的根际土壤为材料,利用实时荧光定量PCR技术,对14种与连作障碍相关的土壤真菌进行了定量检测与分析。结果表明:杨梅根际真菌群体的含量比较丰富;被孢霉属(Mortierella spp.)和轮枝孢属(Verticillium spp.)在发病植株根际的含量均显著高于健康植株,与杨梅衰弱病呈正相关关系;青霉菌属(Penicillium spp.)在发病植株根际的含量显著低于健康植株,与杨梅衰弱病呈负相关关系。本研究建立了杨梅根际土壤真菌的快速检测体系,明确了健康株和衰弱株根际真菌菌群的差异,为杨梅衰弱病的研究和病害防控提供参考。     

深黄被孢霉固态发酵生产油脂的工艺参数及前后底物组成变化规律的研究

本试验旨在探讨深黄被孢霉固态发酵生产油脂的工艺参数及发酵前后底物组成变化规律.分别采用单因素试验设计与正交试验设计优化发酵底物组成及发酵条件,采用化学分析以及扫描电镜分析、X射线衍射分析方法检测发酵前后底物的理化性质,以比较发酵前后底物组成变化规律.结果表明,最适的发酵底物为玉米淀粉和麸皮的混合物;最佳发酵条件为玉米淀...     

东祁连山高寒草地土壤3种高山被孢霉生物学特性的测定

通过对东祁连山高寒草地土壤3种高山被孢霉(Mortierella alpina)生物学特性测定,结果表明:不同处理下3种高山被孢霉的生物学特性具有显著差异,3种高山被孢霉在pH 4～9范围内均能生长,最适宜pH为7;M.ap 27和M.ap 60的最佳光照强度为600lx,而M.ap 9的最佳光强为400lx;3种高山被孢霉的最适湿度为75%;M.ap 27的最适碳源为淀粉,M.ap 60的最适碳源为蔗糖,M.ap 9的最适碳源为葡萄糖;M.ap 27,M.ap 60和M.ap 9的最适氮源均为蛋白胨。