玉米清液发酵生产柠檬酸的工艺研究

[目的]探讨用玉米清液发酵生产柠檬酸的工艺。[方法]以玉米清液为原料,以黑曲霉为菌种,用50L发酵罐进行柠檬酸发酵试验,研究接种量、起始pH值和不同玉米浆添加量对玉米清液发酵柠檬酸产酸的影响,以探讨生产柠檬酸的优化工艺条件以及优化条件下玉米清液发酵柠檬酸的产酸曲线和柠檬酸中黑曲霉的菌丝球形态。[结果]用玉米清液发酵生产柠檬酸的优化工艺条件是：接种量为12%,发酵起始pH值控制为5.6,玉米浆添加量为1.1%,在此条件下发酵72h,产酸可达15.5%,残总糖≤1.1%（W/V）,糖酸转化率为97.1%。优化条件下用玉米清液发酵柠檬酸时,黑曲霉菌丝球伸展均匀,松紧适中,菌丝饱满且分枝多。[结论]该研究为充分利用玉米资源提高柠檬酸的发酵水平提供了参考依据。     

草甘膦降解菌A-F02的分离·鉴定及降解特性研究

[目的]筛选高效草甘膦降解菌株,并研究其降解特性。[方法]从草甘膦生产厂的曝气池活性污泥中分离到1株高效草甘膦降解真菌A-F02,并根据菌株形态特征和核糖体内源转录间隔区（ITS）全序列分析进行菌株鉴定。同时研究菌株对草甘膦的降解特性和影响因素。[结果]经鉴定,菌株A-F02为米曲霉属。在基础盐培养基中,以草甘膦（1000mg/L）为唯一碳源,30℃、150r/min培养7d,草甘膦降解率为86.82%。通过研究添加葡萄糖量、初始pH值、温度及草甘膦浓度对米曲霉A-F02降解能力和生物量的影响结果表明,在添加葡萄糖浓度0.5%,初始pH值7.5,温度30℃,草甘膦浓度1500mg/L的条件下,菌株A-F02的生长量最大,草甘膦的降解效果最佳。[结论]该研究可为草甘膦降解酶的分离纯化提供试验基础。     

米曲霉AS 3.951发酵豆粕对大菱鲆摄食生长的影响

以初始平均体重2.07 ± 0.02g的大菱鲆（Scophthalmus maximus L.）为实验对象,进行为期70 d的摄食生长实验,研究不同添加水平的发酵和未发酵豆粕对大菱鲆摄食生长的影响。用米曲霉（Aspergillus oryzae）AS 3.951对豆粕进行固态发酵。经检测,与未发酵豆粕相比较,发酵豆粕中胰蛋白酶抑制因子、植酸、大豆皂甙、水苏糖和棉籽糖的含量分别下降了46.5％,26.6％、11.7％、30.1％和19.7％。实验共制作6种等氮等能的饲料,其中以全鱼粉饲料为对照饲料;未发酵豆粕蛋白分别替代25％、40％和55％的鱼粉蛋白;发酵豆粕蛋白分别替代40％和55％的鱼粉蛋白。结果表明,饲料中添加一定量的豆粕对大菱鲆的成活率没有显著的影响（P>0.05）。饲料中未发酵豆粕蛋白替代鱼粉蛋白的水平为25％时,对大菱鲆的摄食率、特定生长率、饲料效率和蛋白质效率均没有显著的影响,但替代水平为40％和55％时,以上指标显著降低（P<0.01）。饲料中发酵豆粕替代水平为40％时,未降低大菱鲆的摄食率、特定生长率、饲料效率和蛋白质效率,替代水平为55％时,显著降低大菱鲆的摄食率和特定生长率（P<0.01）。     

黑曲霉HQ-1液体发酵产纤维素酶条件研究

[目的]探讨黑曲霉HQ-1液体发酵产纤维素酶的最适条件。[方法]以1株产酶活力相对较高的黑曲霉HQ-1为出发菌株,采用单因子试验和正交试验对黑曲霉HQ-1液体发酵产纤维素酶的最适条件进行初步研究,并测定了CMC酶（CMCase）和滤纸酶（FPAase）的活力。[结果]影响黑曲霉HQ-1液体发酵产CMCase和FPAase的因素依次是复合碳源的含量、2种碳源的比例、氮源含量和装液量。该菌产CMCase的最适培养基为：麸皮＋玉米秸秆粉15‰（1：1）,NH4Cl2．0‰,其他成分同Mandel’s营养液;产FPAase的最适培养基为：麸皮＋玉米秸秆粉20‰（1：1）,NH4Cl1．5‰,其他成分同Mandel’s营养液。2种培养基的最适pH值和装液量均分别为5．0和50ml／250ml三角瓶。在30℃和170r／min下培养4d后,CMCase和FPAase达到525．2和217．6IU。[结论]该研究为纤维素酶生产菌株的研发提供一定的技术参考。     

Enhancement of Growth and Yield of Glycine max Plants with Inoculation of Phosphate Solubilizing Fungus Aspergillus niger K7 and Biochar Amendment in Soil

Addition of biochar in agriculture soil and bioinoculation of several fungi have been proved to benefit the growth and yield of crops; however, these have been mostly studied separately. Therefore, to perceive the effect of biochar along with Aspergillus niger K7, the present investigation was planned in soybean. Maximum solubilization was found at 20°C in vitro. Further, the strain was morphologically and molecularly identified. In plant-soil experiment, all the treatments showed a significant (p < 0.05) increase in growth, root nodulation, and yield of soybean plants; however, biochar supplemented with K7 treatment was the best. Hence, it can be concluded that the addition of both bioinoculant and biochar simultaneously can be a good practice to improve soil fertility and crop yield. To the best of our knowledge, this is the first report on comparative study of the effect of biochar and phosphorus (P)-solubilizing K7 strain on growth, yield and P uptake in soybean plants grown in Kumaon Himalayas.     

The diagnosis and successful treatment of Aspergillus fumigatus infection of the frontal sinuses and nasal chambers of the dog

Five cases of rhinitis and sinusitis in the dog are presented in which the invading organism was Aspergillus fumigatus . The diagnosis of the condition is described and the radiographic features emphasized. The surgical treatment, post-operative management and successful outcome of the five cases are reported.
Résumé. On présente cinq das de rhinite et de sinusite chez le chien, cas dans lesquels l'organ-isme était l'Aspergillus fumigatus. On décrit le diagnostic de la condition et on souligne les traits radiographiques caractéristiques. On rapporte le traitement chirurgique, la ligne de conduite postopératoire à suivre et la menée à bien des cinq cas.   Zusammenfassung.     

In vitro efficacy of lufenuron against filamentous fungi and blood concentrations after PO administration in horses

Lufenuron is a benzoylphenyl urea-derived insecticide that has been recently introduced as a novel treatment for fungal infections in horses. The purposes of this study were to determine (1) the in vitro efficacy of lufenuron against Aspergillus and Fusarium spp. and (2) the ability of lufenuron to reach efficacious blood concentrations after PO administration in horses. Fungal colonies isolated from diseased equine corneas were tested against lufenuron solutions up to 700 microg/mL. Twenty-one adult horses received 1 of 3 PO lufenuron treatment regimens: 5 mg/kg body weight (BW) q24h for 3 days, 20 mg/kg BW q24h for 3 days, or 60 mg/ kg BW q24h for 1 day. Blood samples were collected up to 96 hours after drug administration and analyzed by high-performance liquid chromatography. Statistical analyses of lufenuron blood concentrations were performed by analysis of variance and Fischer's Least Significant Difference test, with statistical significance set at P < .05. Lufenuron showed no effect on the in vitro growth of Aspergillus or Fusarium spp. Lufenuron was detected in the blood of all but 1 horse and showed no adverse effects. The maximum blood lufenuron concentration (83.5 +/- 58.7 microg/L) was lower than the concentrations proven to be ineffective in vitro in this study. Further therapeutic use of lufenuron as an antifungal agent in horses should be based on proven efficacy against specific strains of clinically relevant fungi with pharmacokinetic data demonstrating sufficient lufenuron concentrations in target tissues.     

Development of a method for the identification, using the polymerase chain reaction, of Aspergillus fumigatus isolated from ostriches

Objective To develop a method for identifying DNA of Aspergillus fumigatus from ostriches, using the polymerase chain reaction (PCR). A fumigatus is the principal causative agent of avian aspergillosis.
Design A biochemical trial.
Sample population Twelve Aspergillus fumigatus isolates and three other Aspergillus species.
Procedure PCR primers that were based on the sequence of the alkaline protease gene from human isolates of A fumigatus were used.
Results We successfully tested the method on ostrich isolates from five states and showed that the test is specific for A fumigatus.
Conclusions In most cases the DNA sequence of A fumigatus isolates from ostriches is similar to that of human isolates. DNA sequences vary significantly among A fumigatus isolates, including those from affected ostriches in the same flock. The genetic variation may be used to trace aspergillus infections in ostrich flocks and determine if the disease is transmitted by contact with infected birds.     

Spore cell wall components ofAspergillus niger elicit downy mildew disease resistance in pearl millet

Elicitors derived from the cell wall of fungi are shown to be active in eliciting resistance in plants against a wide range of pathogens. In the present study carbohydrate components from the autoclaved spore cell wall ofAspergillus niger were prepared as aqueous suspensions and tested for defense response in pearl millet (Pennisetum glaucum (L.) R.Br.) against the oomycetous downy mildew pathogenSclerospora graminicola (Sacc.) Schroet. The aqueous suspension derived from the spore cell wall ofA. niger was used as a seed soak treatment at concentrations of 0.25, 0.5, 1.0, 1.5 and 2.0 mg ml⁻¹ for time intervals of 3, 6, 9 and 12 h. The concentration of 0.5 mg ml⁻¹ for a 6 h soaking period offered 94% seed germination and seedling vigor index increased to 1526. The seed germination and the seedling vigor were significantly higher than the untreated check. Spore cell wall suspension as seed treatment at a concentration of 0.5 mg ml⁻¹ required a 3-day time interval to provide 67% protection against downy mildew. Histological and biochemical studies were conducted to elucidate the mechanism of defense response in treated seedlings uponS. graminicola infection. Resistance host response was detected in the form of lignin and callose deposition in the epidermal cell wall of pearl millet seedlings, which is the site ofS. graminicola infection. A time course study showed rapid and localized deposition of lignin and callose in epidermal cell wall of carbohydrate components-treated pearl millet seedling coleoptiles. Increased levels of the defense-related enzyme peroxidase were detected in the treated seedlings. Peroxidase activity in elicitor-treated samples reached a peak at 8 h post-infection, which was 45% more than in their respective uninoculated control. Characterization of peroxidase isoforms by isoelectric focusing revealed 16 different isoforms, of which pI 6.8, 7.2 and 8.7 increased in elicitor-treated samples uponS. graminicola infection. http://www.phytoparasitica.org posting Nov. 14, 2005.     

绿色木霉、黑曲霉和米曲霉对马铃薯废渣分解能力的研究

本文对米曲霉、黑曲霉和绿色木霉分解马铃薯废渣的能力进行研究。结果表明:1)微生物分解马铃薯废渣的机理是:微生物产生的酶系Ⅰ先将马铃薯渣分解为可溶于水的物质,这些物质又在微生物产生的酶系Ⅱ的作用下,分解成微生物可以直接吸收利用的还原糖,供微生物生长繁殖;2)在这3种菌种中,对马铃薯渣分解能力最强的是米曲霉,在72h内能使马铃薯渣完全分解,且粗蛋白质的含量提高了2.43倍。