强化型EM菌剂对金针菇菌糠堆肥的影响

为提高EM菌剂在菌糠堆肥中的应用效果,加速腐熟进程,改善堆肥质量,采用纤维素酶与木聚糖酶高产菌株黑曲霉SNH-7、蛋白酶高产菌株枯草芽孢杆菌SNK-103与EM菌剂进行复配,研制强化型EM菌剂,并研究其对菌糠堆肥的影响。结果表明：与普通EM菌剂相比,接种强化型EM菌剂的处理堆肥过程中微生物代谢更加旺盛,温度、pH、EC值、总有机碳、可溶性有机碳、总氮、铵态氮、硝态氮、C/N、腐植酸和黄腐酸含量等理化指标的升高或降低幅度更大,腐熟进程加快;成品堆肥的GI提高,C/N降低,总氮、硝态氮、总腐植酸和游离腐植酸的含量升高,生物安全性更好、肥效更高。说明在EM菌剂中补充纤维素酶、木聚糖酶和蛋白酶高产菌株,可强化其对纤维素、木质素和蛋白质的降解能力,在无辅料、高C/N、低pH的不利条件下,添加该菌剂能加速堆肥进程,提高堆肥质量。     

Neuroprotective Metabolites from Vietnamese Marine Derived Fungi of Aspergillus and Penicillium Genera

Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity.     

茶叶微生物固态发酵中咖啡碱降解途径初探

为探究微生物作用下咖啡碱的降解产物与途径,将普洱茶发酵中筛选鉴定的Aspergillus sydowii NRRL250（聚多曲霉）、Aspergillus pallidofulvus NRRL4789、Aspergillus sesamicola CBS137324和Penicillium mangini CBS253.31等优势菌株分别接种至晒青毛茶进行单菌种固态发酵,并采用高效液相色谱（HPLC）测定咖啡碱、可可碱、茶碱的含量,探究微生物对咖啡碱代谢的影响;另外,基于UHPLC-QTOF-MS代谢组学技术,以灭菌处理组（ST组）和原料组（RM组）为对照,对聚多曲霉接种发酵样进行代谢组学分析。结果表明,A. pallidofulvus NRRL4789、A. sesamicola CBS137324和Penicillium mangini CBS253.31等优势菌株对咖啡碱等嘌呤类碱代谢均无显著影响,而在聚多曲霉接种发酵中,咖啡碱含量显著下降（P<0.05）,降幅达83.89%;茶碱含量显著增加（P<0.05）,发酵末期含量为(25.03±1.17) mg·g^-1;而可可碱保持基本稳定。由此可知,聚多曲霉对咖啡碱降解代谢有显著影响。采用UHPLC-QTOF-MS方法检出茶碱、3-甲基黄嘌呤、1,7-二甲基黄嘌呤等9种与咖啡碱降解相关的代谢物。在聚多曲霉作用下,茶碱、3-甲基黄嘌呤、1,7-二甲基黄嘌呤、7-甲基黄嘌呤含量显著提高（P<0.05）。茶碱、3-甲基黄嘌呤、1,7-二甲基黄嘌呤和1-甲基黄嘌呤与咖啡碱及其相关代谢物的N-脱甲基化途径相关。1,7-二甲基尿酸、1-甲基尿酸与咖啡碱相关代谢物的氧化途径相关。由此可知,聚多曲霉为降解普洱茶咖啡碱的优势菌株,且具有将咖啡碱转化为茶碱的潜在能力;在咖啡碱降解代谢过程中,存在聚多曲霉作用下的N-脱甲基化和氧化,并以N-脱甲基化为主。     

Effect of feeding Aspergillus awamori and canola seed on the growth performance and muscle fatty acid profile in broiler chicken

The aim of this study was to examine effects of dietary supplementation with Aspergillus awamori and feeding canola seed on the growth and fatty acid profile in broilers. Twenty‐eight chicks (15 days old) were assigned to the following groups: (1) control, fed a basal diet; (2) awamori, fed the basal diet supplemented with 0.05% A. awamori; (3) canola, fed a diet containing 5% canola seed; and (4) canola + awamori, fed the canola diet supplemented with A. awamori (seven birds/group). Body weight gain was increased by A. awamori but not influenced by canola seed. Breast muscle weight was increased in either awamori or canola groups. Although plasma triglyceride and cholesterol were decreased by feeding A. awamori or canola seed, fat content in the breast muscle were increased, accompanied by decrease in saturated fatty acids and increase in unsaturated fatty acids. Moreover, decreased thiobarbituric acid reactive substance and increased α‐tocopherol content in the breast muscle was observed in all experimental groups. In conclusion, these results suggested that feeding canola seed and A. awamori might improve growth performance, and modified muscle fatty acid profile and α‐tocopherol content, suggesting that they may improve meat quality.     

普洱茶渥堆发酵中可降解咖啡碱真菌菌株的筛选和鉴定

为了在普洱茶渥堆发酵中筛选出可降解咖啡碱的菌株,采用咖啡碱液体筛选培养基从不同阶段普洱茶发酵样中筛选目标菌株,结合菌落特征、分生孢子结构以及18 S r DNA序列对目标菌株进行鉴定。并将目标菌株接种至茶叶内进行单菌种发酵,通过高效液相色谱法(HPLC)测定咖啡碱、茶碱、可可碱、3-甲基黄嘌呤等嘌呤碱含量。结果表明,在普洱茶发酵样中筛选出一株有效降解咖啡碱的菌株,此菌株在48 h内对咖啡碱的降解率为87.7%。经鉴定为聚多曲霉(Aspergillus sydowii),序列相似性为99.8%。在聚多曲霉茶叶单菌种发酵中,咖啡碱含量急剧下降,在发酵结束时仅占干物质重的(0.414±0.077)%;茶碱质量分数大幅度上升,由最初的不足0.1%上升至(2.129±0.246)%,成为主要的嘌呤碱;可可碱含量无显著变化(P0.05);3-甲基黄嘌呤有大幅度增加,增幅达130%。本文首次从发酵茶叶中筛选出可降解咖啡碱的菌株,探究了微生物发酵中咖啡碱的转化产物,为低咖啡碱普洱茶的开发提供了菌种。     

Distribution and genetic diversity among Aspergillus flavus isolates across three agro-ecologies essential for maize cultivation in Ghana

Fungal mycotoxins are important contaminants of agricultural commodities that pose serious concerns to producers, consumers and exporters. Aflatoxin is a carcinogenic metabolite produced by the fungi Aspergillus flavus and A. parasiticus. These fungi and other mould species living in the soil contaminate several crops including maize. This study was undertaken with the following objectives: (i) to assess the presence of A. flavus and other moulds in Ghanaian soil; (ii) to determine the distribution and density of A. flavus under three agro-ecologies noted for major maize production; and (iii) to assess the effect of percentage of carbon (C) and nitrogen (N) and soil pH on A. flavus population densities and diversity in the isolates found across the agro-ecologies. The data showed seven moulds that were common across the agro-ecologies. Significant differences (P < 0.05) were observed in the A. flavus density and distribution within and across these agro-ecologies. Fumesua soils recorded the highest levels of A. flavus (1.185 × 10³ cfu g⁻¹) while Akomadan recorded the least (9.76 × 10² cfu g⁻¹). Percentage available C, N and soil pH did not significantly influence A. flavus density. The A. flavus isolates identified in this study varied in genetic sequence within the aflatoxin gene cluster, but these differences were not distinguishable by origin.     

花生抗黄曲霉相关基因PnLOX2的原核表达及RNAi载体的构建与转化

本研究对利用基因芯片技术从抗、感黄曲霉花生品种中分离出的差异表达基因PnLOX2进行原核表达,得到分子量为121.5 kD的融合表达产物;构建了PnLOX2基因的3'端反向重复结构并转化花生,得到了转基因花生苗,为反向鉴定PnLOX2基因在花生抗黄曲霉侵染过程中的功能奠定基础。     

黑曲霉菌渣资源化再利用途径分析

黑曲霉菌渣是黑曲霉发酵法生产葡萄糖酸钠后产生的废弃物，其资源化利用已成为企业扩大生产亟需解决的问题。对该菌渣有效成分检测得知，该菌渣有害金属元素均小于城镇垃圾农用控制标准、有机-无机复混肥料控制标准和鱼粉、猪、家禽添加剂预混合饲料卫生指标，有机质含量符合有机肥料中的有机质含量指标，总糖、粗纤维、粗蛋白、脂肪等营养成分含量较多，同时也含有丰富的N、P、K、Ca、Mg、Fe等元素，可从有机肥料和禽畜饲料方向进行资源化利用，有利于减轻环境污染及实现变废为宝，具有积极的社会、经济和生态效益。     

花生黄曲霉生长预测模型的研究

通过对分离自花生的黄曲霉LYYSS03-3在不同温度(15-35℃)、不同相对湿度(水活度分别为0.5,0.7,0.9)下的菌落生长特性进行检测,采用Boltzmann和Logistic 模型对黄曲霉的生长曲线进行拟合,结果表明,在适宜温湿度阶段,花生黄曲霉的生长曲线更适合用Boltzmann模型拟合.     

黑曲霉、荧光假单胞菌去除污水中重金属试验研究

将黑曲霉和荧光假单胞菌引入到传统的卡鲁塞尔氧化沟工艺模型中,参照规范中氧化沟的水力停留时间,分别选取12、16、20、24、28、32和36 h水力停留时间进行试验,研究了不同水力停留时间2种菌种对重金属Cd、Cr、Pb和Cu的吸附降解规律.对水力停留时间为36 h进行了接种对比试验研究.研究发现接种2种菌种后,当水力...