洛伐他汀产生菌土曲霉原生质体的制备与再生

报道了产生降血脂药物洛伐他汀（lovastatin)的土曲霉（Aspergillus terreus)的原生质体的制备与再生条件及原生质体形成过程,结果表明用溶壁酶5mg.mL^-1,Zymolyase 20T 2.5mg.mL^-1和蜗牛酶2．5mg.mL^-1配制的混合酶液,可制备出土曲霉生质体;其最佳酶解温度为34℃,作用5h,原生质体再生率达17％以上。     

狼毒根提取物的杀虫活性测定

利用瑞香狼毒根乙醇提取物(SCEE)对榆白长翅卷蛾5龄幼虫和麦二叉蚜进行触杀作用测定。结果表明,SCEE对榆白长翅卷蛾5龄幼虫有很强的触杀活性,当浓度为20mg/ml、10mg/ml、6.67mg/ml、5mg/ml、4mg/ml时,其校正死亡率分别为100％、100%、98.2%,95.4％、83.18%。SCEE对麦二叉蚜的触杀活性较差,最高浓度20mg/ml时,其校正死亡率仅为22.54%。     

构建家禽坚强的免疫体系

<正>目前我国的养殖业多是中小分散状态,疾病的诊治又存在"老病未去,新病又添;新病未治,新病又变;混合感染,用药紊乱;药效难显,治疗棘手"的问题,病毒的毒株变异增多,混合感染严重,耐药菌株越来越厉害。今天笔者就针对目前的养殖状况谈谈     

红曲霉发酵对鳙鱼肉糜品质和生物活性影响研究

以红曲霉发酵鳙鱼肉糜,并对其发酵过程中品质和生物活性变化进行测定。结果表明,红曲霉发酵可使鳙鱼肉糜pH值略微上升,改善产品色泽和抑制挥发性盐基氮的生成,促进鳙鱼肉糜蛋白质的降解和游离氨基酸的生成,还可增强鳙鱼肉糜的抗氧化与血管紧张素转化酶抑制活性。     

饲料霉变和有效防霉问题

<正>饲料是畜禽机体维持正常生命活动和生产性能所必需的物质和能量来源。饲料安全和卫生直接关系到饲喂畜禽的健康和生产性能,间接影响到人类的安全与健康。饲料在生产、加工、运输、贮存及使用等过     

水产饲料中的霉菌毒素

<正>霉菌毒素是霉菌产生的次级代谢产物。霉菌在农作物收获前、收获后及运输和仓储的过程中都可生长并产生霉菌毒素。造成鱼及其它养殖动物生长减慢、健康状况受损的霉菌毒素都是由黄曲霉菌、青霉菌和镰刀霉菌产生     

蛋用雏鸡曲霉菌病的诊断与治疗

曲霉菌病是由黄曲霉菌、烟曲霉菌、单端孢霉菌、赭曲霉毒菌等引起的一种真菌性疾病。夏季温、湿度高，最易发生蛋用雏鸡曲霉菌病。     

米曲霉培养物和艾美福对绵羊瘤胃及消化道内营养物质流通规律的影响

利用"营养灌注"法测定瘤胃发酵动力学参数、纤维物质及营养物质在绵羊消化道的流通规律,比较研究经本实验室发酵的米曲霉培养物与艾美福的应用效果。结果表明:瘤胃液相体积和滞留时间艾美福组最大,固相体积和滞留时间米曲霉组最大;相同消化部位不同处理时间营养物质流通量差异不显著(P>0.05),但添加米曲霉培养物降低了营养物质流通量;添加米曲霉培养物对绵羊消化道相同部位DM、OM、NDF和ADF的消化率影响不显著(P>0.05),但提高了营养物质消化率。     

红曲霉液体深层发酵生产红曲色素条件的研究

[目的]确定红曲霉产生红曲色素最适宜的培养基配方和培养条件.[方法]采用改变单一变量的方法,测定红色素色价的变化规律,确定红曲霉产生红色素最适宜的培养基配方和培养条件.[结果]试验确定了红曲霉产生红色素最适宜的培养基配方为：葡萄糖5％,酵母粉2％,CaCO30.2％,NaCl0.1％,MgSO4·7H2O 0.1％,KH2PO40.2％,吐温200.05％;最适宜的培养条件为：pH 6.0,装液量为60 ml/250 ml三角瓶中接种10％ （1/6）种龄为72 h的液体种子,30 ℃恒温摇床上振荡培养,转速为180 r/min,发酵6d,红曲色素色价可达19.2 U/ml.[结论]该试验可为工业上大规模生产红曲红色素提供理论依据.     

Gene Expression and Fungal Morphology in Submerged Culture Using Whole Barley of Aspergillus kawachii

The authors described a novel submerged batch culture system that produced high levels of amylase by Aspergillus kawachii using whole barley （WB）, the surface of which is covered by its husk. In this study, detailed analyses determining the amylase activities, residual sugars, fungal morphology and expression levels of genes were performed in a submerged culture using WB to address the mechanism underlying high amylase productivity in A. kawachii. High levels of glucoamylase and acid-stable u-amylase were produced in this culture, and expression levels of amylases, as well as glucose-repressive genes including high-affinity glucose transporter and peroxidase/catalase were also high. On the other hand, the morphology of mycelia was altered, with swollen, bulbous, multi-septum hyphae and conidiophores that normally form in a solid culture being partially generated. Furthermore, cell cycle and post-translational modification-related gene expression levels were altered, and were similar to those in the solid culture. These findings suggest that high amylase productivity in the submerged culture using WB is accompanied by both the up-regulation of amylase genes and activation of post-translational modifications due to fungal morphological changes being brought closer to those in the solid culture.