Synthetic medium for cultivating Bacillus thuringiensis

Bacillus thuringiensis subsp. galleriae 69/6 was cultivated in a synthetic medium containing 5 amino acids and nicotinic acid. The dynamics of the culture growth and amino acid assimilation were studied in this medium and in a medium containing yeast extract. The phase of spore germination increased, the yield decreased and the maximal growth rate became higher when the culture grew in the synthetic medium. The percentage of thermoresistant spores was slightly lower in the synthetic medium comparing to the medium with yeast extract.     

Sauerkraut waste: a favorable medium for cultivating yeasts

Sauerkraut waste was found to be more favorable for cultivating yeasts than malt extract broth and as good or better than peptone dextrose broth.     

Use of a synthetic medium for cultivating pathogenic anaerobes]

It was shown that a synthetic medium suggested by the authors earlier was useful for the growth and toxin formation of Cl. tetani, Cl. botulinum and Cl. perfringens, types B and E. A study of the character of growth and toxinogensis, microscopic examination of morphology of culture cells and results of passages showed the suggested synthetic medium to be of value; a possibility of its application for studying the nutrient requirements and the role of individual components of the nutrient media in the process of growth and toxinogenesis was also demonstrated.     

L-缬氨酸产生菌的选育及其发酵培养基的优化

以黄色短杆菌(Brevibacterium flavum)NJ-237为出发菌株,通过梯度传代适应性培养及同浓度药物平板富集培养的方式,逐步提高菌体的抗药物性能,获得了1株耐高糖和耐高浓度α-氨基丁酸(-αAB)的菌株NJ-2372。在单因素实验的基础上,利用响应面分析法对影响该菌株L-缬氨酸(L-Val)产量的3个重要因素玉米浆、生物素(VH)、硫胺素(VB1)的添加量进行优化。结果表明:当玉米浆、VH、VB1最佳添加量分别为11 g/L、35μg/L和101μg/L时,摇瓶发酵72 h,L-Val摇瓶发酵产量达到52.9 g/L。     

缺陷短波单胞菌高产L-脯氨酸菌株的选育及其发酵条件优化

以缺陷短波单胞菌(Brevundimonas diminuta)JNPP-1为出发菌株,利用紫外诱变及亚硝基胍复合诱变的方式,获得1株遗传性能稳定、可抗磺胺胍、能耐高渗透压以及能以琥珀酸钠为唯一C源的、在培养基上有生长优势的L-脯氨酸高产菌株JNPP-NSS(SGr、Sucg、NaClr)。经发酵条件优化后,L-脯氨酸的最高质量浓度可达47.3 g/L,与出发菌株相比提高了45.1%,生产速率由0.45 g/(L·h)提高到0.78 g/(L·h)。     

An evaluation of a nutrient medium for isolating and cultivating Helicobacter pylori

Selective Helicobacter agar containing the selective supplement and blood, adding ex tempore, for the isolation and cultivation of H. pylori was developed. The Helicobacter agar was studied with the use of 5 newly isolated H. pylori strains, 13 bacterial associated cultures, as well as 21 inoculated biopsy specimens of the gastric and duodenal mucosa of patients with peptic ulcer. The study revealed that Helicobacter agar ensured the growth of H. pylori and their isolation from clinical material. The positive results after the inoculation of the specimens of biopsy material on Helicobacter agar and control media was 85%. In addition, the study of Helicobacter agar showed that it also exhibited pronounced selective properties with respect to bacterial associations, not inhibiting the growth of Helicobacter organisms and retaining their main biological properties. It is possible to recommend Helicobacter agar for use in laboratory practice in diagnosing Helicobacter-associated diseases.     

固定化植物乳杆菌的制备及其发酵条件优化

采用海藻酸钠包埋植物乳杆菌并通过测定固定化细胞发酵清液的抑菌效果,优化得到的固定化最佳工艺条件为:海藻酸钠浓度为3%,CaCl2浓度为1.5%,菌悬液体积为3.5 mL(4.0×108 cfu/mL).固定化细胞重复发酵多批次效果良好.固定化细胞发酵条件优化结果表明:最适pH为7.0,最适温度为36℃,培养基中添加0....     

一株中性蛋白酶产生茵的筛选及产酶条件优化

从酒曲中筛选出一株高产蛋白酶的菌株,命名为OPY6,初步鉴定为假单胞菌Pseudomonassp．,经Plackett．BurmanDesign设计和Box．Behnken响应面设计对其产酶培养基做了优化,最优产酶条件为：葡萄糖2．83％,淀粉0．87％,酵母膏0．55％,氯化钙0．001％,氯化钠0．5％,黄豆粉1％,初始pH=7．0,在最佳培养基添加量下蛋白酶活提高到134．718U／mL;又对该酶在水产蛋白降解过程中的酶解效果进行了评价。     

阿拉伯胶酶产生菌株的筛选及其发酵培养基的优化

从土壤中筛选产阿拉伯胶酶的微生物菌株,并通过紫外诱变选育后得到高产突变菌株ZHB05F,依据菌落和孢子形态特征初步鉴定为镰刀茵(Fusarium sp.).通过单因素试验,优化了产酶培养基的主要组分的浓度和pH值,得到最佳的产酶发酵培养基组成为:阿拉伯胶30 g/L,(NH4)2SO4 8 g/L,K2HPO4 1g/...     

1,3-丙二醇产生菌的诱变育种及培养基优化

以实验室自然筛选的克雷伯氏杆菌(Klebsiella sp.)为出发株,采用紫外诱变及亚硝基胍和超声波协同处理获得一株1,3-丙二醇高产突变株。在摇瓶发酵中,其产1,3-丙二醇产量由17.39 g/L提高到24.11 g/L,提高38.64%。变异株经10次传代培养,发酵能力稳定。对发酵培养基成分进行了优化,优化后1,3-丙二醇产量为30.05g/L,为优化前的1.25倍。     

Chemiluminescence of copper nanoclusters and its application for trihexyphenidyl hydrochloride detection

Chemiluminescence (CL) of copper nanoclusters (CuNCs) induced by cerium (IV) (Ce(IV)) or potassium permanganate (KMnO₄) in acidic medium was observed. The potential application of CuNCs CL in analytical chemistry was also demonstrated using trihexyphenidyl hydrochloride (THP) as an example based on its enhancing CL intensity for the CuNCs–Ce(IV)/KMnO₄ systems. The excited state of the CuNCs acted as a luminophore in the CuNCs–Ce(IV) system, while CuNCs played the role of reductant in the CuNCs–KMnO₄ system. The increased CL intensity for Ce(IV)–CuNCs system was proportional to the THP concentrations in the range of 0.1 to 10.0 μM. The detection limit was 49.0 nM and the relative standard deviation was 2.2% for 2.0 μM THP (n = 11). The proposed method was applied to detect THP in pharmaceutical formulations and human plasma samples.     

一株产表面活性剂细菌鉴定及发酵条件优化

本文利用16S rDNA序列并结合形态学特征,鉴定实验室前期从油污土壤中分离的产表面活性剂菌株1098-3为大肠埃希氏菌(Escherichia coli).通过单因子实验初步确定了其产生表面活性剂的最适条件:37℃,初始pH7.0,转速200 r/min,培养基配比为可溶性淀粉2.5％,胰蛋白胨1.5％,氯化钠0.3％,磷酸二氢钾0.5％,氯化钙0.004％,硫酸铵0.6％,硫酸镁0.07％,酵母粉0.06％,500 mL三角瓶装液量为200 mL.在此条件下,发酵液表面张力由69.3 mN/m降至34.3mN/m,此时发酵液中表面活性剂相对浓度(RBC)为500.     

溶藻放线菌AN02的筛选及其培养条件的优化

探讨了开发利用土壤放线菌资源来进行水华防治的新途径。从土壤中分离到13株具有溶藻活性的放线菌菌株,经过进一步筛选得到AN02菌株,其胞外代谢产物对铜绿微囊藻具有较好的抑杀作用。研究了不同培养条件对AN02溶藻活性的影响,结果发现pH为7.5,28℃,培养6 d时的溶藻效果最好。此外,较强烈的振荡和充分的溶氧也有利于提高溶藻效果。     

一株CX-DBT脱硫菌的筛选及发酵条件优化

【目的】从大型工业油田石油污染土样中分离鉴定一株能专一性脱除CX-DBT的脱硫菌株,分析其对CX-DBT的脱硫途径,并确定菌体最优发酵条件。【方法】以二苯并噻吩(DBT)为唯一硫源底物,多次富集并分离可代谢CX-DBT菌株,通过形态学、生理生化实验及16S rRNA基因序列分析对筛选菌株JDZX13进行鉴定。采用GC-MS鉴定菌株对CX-DBT的代谢产物,确定其相应的脱硫途径。通过单因素发酵实验确定最佳碳源、氮源、微量元素、MgCl_2、温度及p H的水平范围,并采用正交实验进一步优化。【结果】该菌株鉴定为戈登氏菌属,命名为戈登氏菌JDZX13(KP993297),其CX-DBT代谢途径为"4S途径"。最佳发酵条件为:蔗糖15.0 g/L、NH_4Cl_2.0 g/L、MgCl_2 0.1 g/L、微量元素1.0 m L/L、pH 7.0、温度35°C。【结论】获得一株通过"4S途径"代谢CX-DBT的脱硫菌株JDZX13,经过进一步优化实验,强化了菌株的生长和脱硫能力,该研究结果对石油生物脱硫技术的开发具有重要参考意义。     

脱落酸产生菌的筛选及其产酸条件优化

利用马丁-孟加拉红培养基由20份土壤样品和2份植物病叶样品中分离出57株真菌,分别对其进行液体培养,通过各菌株发酵液抑制莴苣种子发芽的方法筛选得到一株脱落酸产生菌NX-53,通过L9(34)正交实验对其产酸条件进行了优化,该菌株产脱落酸的培养基配方和培养条件如下:葡萄糖25g/L,维生素B11.25mg/L,谷氨酸单钠盐3.0g/L,MgSO4·7H2O 0.2 g/L,KCl 0.5 g/L,CaCO3 5 g/L,KH2PO4 0.8 g/L,FeSO4·7H2O 0.5mg/L, ZnSO4·7H2O 2.5mg/L,CuSO4·5H2O 4mg/L,250mL摇瓶装液量50mL,28℃、150r/min培养7d.优化条件下菌株NX-53的脱落酸产量可达276 mg/L.     

Impact of heavy metals on the trophic activity of daphnia depending on feeding conditions and age of crustaceans

This paper studies how exposure conditions affect the trophic activity of Daphnia crustaceans and their sensitivity to heavy metals. To register the trophic activity of crustaceans, the change in intensity of the zero level of rapid fluorescence in chlorella alga utilized as feed is used. The optimal conditions (stocking density, age of test organisms, feeding schedule, and exposure time) are determined under which a high level of the trophic activity and sensitivity of crustaceans to pollution are registered. An experimental design is suggested in which crustaceans are first exposed to a toxicant and then a suspension of the alga is introduced into a cultivation medium.     

4,4,4-三氟乙酰乙酸乙酯羰基还原酶产生菌的筛选及产酶条件研究

对实验室保藏菌种进行筛选,得到一株葡萄汁酵母Saccharomyces uvarum SW-58,对其产酶条件进行优化,其发酵培养基组成:醋酸钠60 g/L,玉米浆30 g/L,KH2PO46 g/L,MgSO4.7H2O 1 g/L;培养条件为:发酵温度30℃,初始pH 6.0,发酵周期36 h。4,4,4-三氟乙酰乙酸乙酯羰基还原酶酶活最高可达388.1 U/L,产物的浓度由优化前的3.5 g/L提高到4.6 g/L,所得产物的光学纯度由优化前的60.8%e.e.提高到85.0%e.e。     

细菌培养基中营养物质的代谢及优化方法

细菌培养基是细菌体外生长的基质,其中营养物质是细菌生长、繁殖的基本成分。因此,探索培养基中营养物质的代谢,优化培养基配方,对细菌体外培养的研究及规模化生产有着重要的指导意义。现就细菌培养基分类、营养物质、细菌在营养物质中的代谢及培养基优化方法等方面予以总结。