黑曲霉GD-6纤维素酶液体发酵条件的研究

采用黑曲霉 (Aspergillusniger)GD 6液体发酵生产纤维素酶 ,研究了碳源、氮源、培养基起始 pH值、接种量、摇床转速、通气量对该菌株产纤维素酶活力的影响。结果表明 ,GD 6的最适发酵温度为 2 8～ 3 0℃ ,产酶pH为 5 .5～ 6.0 ,摇床最适转速为 1 5 0r/min ,最佳接种量为 1 0 %。在以 6.0 %稻草粉为碳源、1 %豆饼粉为氮源时产酶活力最高。在最适培养条件下 ,发酵周期为 1 2 0h,发酵液中CMC酶活为 1 88.6U/mL ,FP酶活为 2 7.0U/mL。     

青霉P-1产植酸酶发酵条件的研究

研究了碳源、氮源等对青霉(Penicillium)P-1液体发酵产植酸酶的影响。最佳碳源为蔗糖,最佳氮源为蛋白胨和硝酸铵。最适发酵产酶条件为培养温度30℃,发酵培养基最适pH 5,摇瓶装液量10%,接种量4%,摇床转速120 r/min,培养时间96 h,最高酶活性可达78 U/L。     

正交实验优选光合细菌混合菌群产氢的最佳条件

对光合细菌混合菌群产氢影响因子进行了实验研究。通过单因素实验和正交实验, 系统考察了碳源、氮源、碳源浓度、氮源浓度、初始pH值、光照方式、接种量等因素对产氢量的影响, 实验得出最佳工艺条件为: 采用3号菌群, 碳源为葡萄糖, 碳源浓度为3 g/L, 氮源为尿素, 氮源浓度为9 g/L, 接种量为10%, pH值为8.5, 光照方式为12 h光照-12 h黑暗交替光照, 培养温度为30°C。菌种、碳源、碳源浓度、氮源是影响产氢量的重要因素。     

培养基的组成及培养条件对茶树菇多糖产量的影响

本文研究了不同碳源,氮源以及发酵条件对茶树菇多糖产量的影响,并通过正交试验优化了深层发酵培养基。结果表明,茶树菇深层发酵最适的碳源为玉米粉,最适的氮源为酵母粉,最适的发酵条件为温度25℃,摇瓶装液量100mL/250mL,转速150r/min,接种量15%,起始pH自然。     

1株抑制土传病原菌且产纤维素酶芽胞杆菌筛选及产酶条件的研究

通过刚果红染色法和DNS分光光度法对6种芽胞杆菌分泌胞外纤维素酶进行筛选,再通过管碟法测试对5种病原菌的抑菌作用,得到1株芽胞杆菌（菌株编号为X-02）酶活达182.5 U/mL,而且对几种土传病害有抑制作用。并对其产酶发酵培养基碳源、氮源及初始pH、发酵温度、接种量、摇瓶转速和时间进行优化,结果显示该菌株最佳碳源是2%CMC-Na,其次是葡萄糖,二者产酶之差只为21 U/mL。考虑大量生产的成本和方便性（CMC-Na溶解慢）,选择葡萄糖为碳源,氮源为2.0%蛋白胨与酵母膏复合氮源,在pH值为8.0、温度37℃、接种量为2%、转速为180 r/m in、时间48 h条件下酶活达到391.0 U/mL酶液,比优化前提高了2.1倍。     

解淀粉芽孢杆菌M1摇瓶发酵条件优化及脱氮性能评价

旨在提高解淀粉芽孢杆菌M1液体发酵产芽孢量,并考察其对实际废水的反硝化脱氮效果。首先采用单因子实验研究了碳源、氮源、初始pH值、温度、转速和装液量等因子对M1液体发酵产芽孢量的影响。然后对其中显著性因子:氮源浓度、接种量、装液量、温度4个因素进行正交试验,进一步优化发酵条件。结果显示,优化后的培养基成分为:5 g/L碳源(可溶性淀粉)、10 g/L氮源(酵母粉∶蛋白胨=2∶1)、1 g/L NaCl;最佳培养条件为:初始pH6.5、发酵温度34℃、摇床转速180 r/min、培养瓶装液量30%、接种量7%。在此条件下,芽孢杆菌M1芽孢数可达到6.8×108 CFU/mL,高于优化前的2.08×108 CFU/mL。将芽孢杆菌M1投加于反应器中,与不加菌种相比,反硝化脱氮效果提升15%-34%。     

产酸丙酸杆菌生长特性及5L罐发酵动力学研究

论文在摇瓶水平对产酸丙酸杆菌基本生长特性（温度、pH、摇床转速、接种量、种龄等）、碳源、氮源利用情况、产物抑制及5 L罐发酵动力学进行了研究。结果表明,该菌在32℃,初始pH 6．5,摇床转速150 r/min,接种24 h的种子液,接种量为5％条件下,产酸丙酸杆菌生长及产酸水平达最高值;该菌可利用碳源十分广泛,但对氮源要求比较高,只可利用有机氮源;在不同初始葡萄糖浓度下,产酸丙酸杆菌生长及产酸水平差异不大,无明显底物抑制现象;在2g/L的初始丙酸盐浓度下,该菌生长受到明显抑制;在5L发酵罐中,初始葡萄糖浓度为58．8 g/L,发酵72 h,葡萄糖消耗完全,丙酸终浓度达22．4 g/L,丙酸得率和产率分别达0．381 g/g和0．295 g/（L·h）,丙酸占总酸比例达72．10％。     

甲壳素脱乙酰酶产生菌产酶条件的优化

采用斜面培养和液体发酵培养产甲壳素脱乙酰酶的真菌构巢曲霉,并且研究了产酶条件。结果表明,构巢曲霉的最适产酶条件为：发酵培养基初始pH值为6.5、发酵时间为96h、培养温度为31℃、碳源浓度为2%、氮源浓度为2%、金属离子浓度为0.01mol/L、接种量为6%。     

高产洛伐他汀棒曲霉菌株的筛选、鉴定及发酵条件优化

从不同生境(食品、土壤、空气、有机质等)收集到的自然发酵样品中分离得到150株曲霉属菌株.用高效液相色谱(HPLC)法检测发酵液中洛伐他汀(Lovastatin)含量,筛选获得1株稳定高产Lovastatin的曲霉菌株(编号:Ac-32).根据菌落形态特征并结合18 S rDNA测序,鉴定其为棒曲霉(Aspergillus clavatus).通过摇瓶发酵单因素实验优化了碳氮源种类、碳氮源含量、碳氮比(C/N)、发酵温度、初始pH、转速、种龄和接种量,确定了棒曲霉菌株Ac-32摇瓶发酵产Lovastatin的适宜条件为:乳糖为碳源、蛋白胨为氮源、碳源含量为100 g/L、氮源含量为12 g/L、碳氮比(C/N)为15:1.8、温度28℃、转速180 r/min、初始pH 5.2、种龄4 d、接种量6%.采用Minitab 17软件的P-B实验设计法,筛选对Lovastatin产量有显著影响的因素为:温度、pH、碳源含量和氮源含量.根据P-B实验结果,运用响应面法分析,确定棒曲霉菌株Ac-32产Lovastatin的最优条件为:碳源含量100 g/L,氮源含量11.8 g/L,温度28℃,pH 5.2.在此条件下,Lovastatin最高产量为236.221μg/mL.     

产青霉素酶枯草芽孢杆菌发酵条件的优化

目的:对一株产青霉素酶的重组枯草芽孢杆菌(Bacillus subtilis DB104/pWB-pemp)的摇瓶发酵条件进行优化.方法:利用单因素实验及正交实验等方法考查重组菌摇瓶发酵条件,研究不同浓度的碳源、氮源、金属离子、磷酸盐及不同pH、接种量、装液量和温度等条件对产青霉素酶的影响.结果:重组菌株摇瓶最适发酵条件为pH 7.0、接种量3％、装液量14％、发酵温度37℃,培养基成分为2％蔗糖、3.5％酵母膏、0.1mmol/L镁离子、0.4％磷酸盐.结论:最优条件下,发酵36h,产酶活力达到2227.8U/mL,为先前研究结果(1 580 U/mL)的1.41倍,为重组菌的大规模发酵生产奠定了基础.     

水溶性红曲黄色素的表征及其稳定性

以含硫化合物还原红曲色素,红斑素和红曲红素分子中的环羰基还原成羟基,得到水溶性红白曲黄色素.以 UV-Vis、IR和(?)H-~(13)CNMR对其结构进行了表征.该色素的吸光度随pH增大而略呈上升趋势,避光可明显提高其稳定性.除Mg~(2 )在pH9下使其溶液产生沉淀外,Sn~(2 )、Ca~(2 )、Fe~(3 )和AI~(3 )均不影响其稳定性.不同pH和温度下加热实验结果表明,酸性条件对其热稳定性影响较大.     

Production of water-soluble yellow pigments via high glucose stress fermentation of Monascus ruber CGMCC 10910

Monascus pigments are secondary metabolites of Monascus species and are mainly composed of yellow pigments, orange pigments and red pigments. In this study, a larger proportion of Monascus yellow pigments could be obtained through the selection of the carbon source. Hydrophilic yellow pigments can be largely produced extracellularly by Monascus ruber CGMCC 10910 under conditions of high glucose fermentation with low oxidoreduction potential (ORP). However, keeping high glucose levels later in the culture causes translation or a reduction of yellow pigment. We presume that the mechanism behind this phenomenon may be attributed to the redox level of the culture broth and the high glucose stress reaction of M. ruber CGMCC 10910 during high glucose fermentation. These yellow pigments were produced via high glucose bio-fermentation without citrinin. Therefore, these pigments can act as natural pigments for applications as food additives.

     

高产红曲黄色素菌株的选育

利用紫外、硫酸二乙酯、氯化锂和亚硝基胍复合诱变的方法,选育到一株高产黄色素的红曲霉突变株MYM2.经过稳定性实验证明,诱变得到的菌株稳定性较好,液态发酵试验黄色素色价达到100U/mL以上,黄色素色调达到3.5左右.此黄色素在300nm～600nm波长之间只有一个在410 nm附近的最大吸收峰,在pH 3～8之间稳定性较好.当pH小于3时,红曲黄色素不稳定,黄色素溶液变混浊,放置后有沉淀产生.     

Effect of pH and nitrogen source on pigment production by Monascus purpureus

The effect of pH and nitrogen source on pigment production by Monascus purpureus 192F using glucose as the carbon and energy source, was studied in pH-controlled, batch fermentor cultures using HPLC analysis to determine individual pigment concentrations. A maximum of four pigments were detected in fungal extracts. These were the yellow pigments monascin and ankaflavin, the orange rubropunctatin and the red pigment monascorubramine. Monascorubramine was present as the major product in all instances. Fungal growth and ankaflavin synthesis were favoured at low pH (pH 4.0), whereas production of the other pigments was relatively independent of pH. The nature of the nitrogen source affected fungal growth and pigment production, independent of pH. Ammonium and peptone as nitrogen sources gave superior growth and pigment concentrations compared to nitrate. Ankaflavin was not detected in nitrate cultures. The highest red pigment production was obtained using a glucose-peptone medium at pH 6.5, due to the secretion of red pigments into the medium under these conditions. Correspondence to: M. R. Johns     

Production of pigments byMonascus purpureus using sugar-cane bagasse in roller bottle cultures

Solid-state fermentation, using sugar-cane bagasse, and submerged fermentation, using a semi-synthetic medium, were performed for pigment production byMonascus purpureus in both stationary and rotary conditions. Rotary cultures gave higher yields of crude red and yellow pigments than stationary cultures whereas twice the amount was synthesized at an earlier time (day 8) in liquid medium (1,285U yellow pigment/bottle, 1,728U red pigment/bottle). Supplementing the liquid medium with 0.6% (v/v) corn oil doubled the extracellular pigment yield but halved fungal growth.     

Improved fermentative production of Monascus pigments in roller bottle culture

The quantities and qualities of Monascus pigments produced by the filamentous fungus Monascus anka in batch submerged, agar surface, and roller bottle cultures were compared. In roller bottles, the fungus became attached to the wall of the culture vessels and produced a larger quantity of both intracellular (1508 absorbance units g⁻¹ cell mass) and extracellular (27 absorbance units g⁻¹ cell mass) Monascus red pigments, a yield that was about 10-fold greater than that of batch submerged and agar surface cultures. The optimum time required for maximum pigment production was reduced from 7 days in batch submerged or agar surface cultures to 4 days in roller bottle culture. In the roller bottle culture, the ratio of red to yellow pigments was also greatly increased. The advantage of the rotating vessel might be due to a combination of factors, including better gas exchange, higher medium pH, efficient pigment secretion, solid support for mycelium, and retarded conidiation.     

微生物黄色素的研究进展

对来源于微生物的天然黄色素的研究进行了详细概述, 尤其对红曲黄色素的生产、安全性以及黄色素的合成代谢机理研究进行了详细论述, 最后对红曲黄色素的应用前景及其未来研究重点进行了展望, 并对研究中存在的问题进行了分析。     

红曲霉变异株A6产色素发酵条件研究

本文对红曲霉变异株Ａ６进行了产红曲色素发酵条件试验,发现在以６％饴糖为碳源,以０３％ＮａＮＯ３为氮源的培养基,初始ｐＨ４０～４５,接种量为１５％时产色素浓度最高。同时,考察了整个发酵过程中ｐＨ,残糖量与色素生成浓度的关系,认为发酵周期拟控制在８０～８５ｈｒ为宜。本试验还发现在发酵过程中补加适量饴糖有利于产红曲色素     

Growth kinetics of biopigment production by Thai isolated <Emphasis Type="Italic">Monascus purpureus</Emphasis> in a stirred tank bioreactor

Monascus purpureus is a biopigment-producing fungi whose pigments can be used in many biotechnological and food industries. The growth kinetics of biopigment production were investigated in a liquid fermentation medium in a 5-l stirred tank bioreactor at 30°C, pH 7, for 8 days with 100 rpm agitation and 1.38 × 10⁵ N/m² aeration. Thai Monascus purpureus strains TISTR 3002, 3180, 3090 and 3385 were studied for color production, growth kinetics and productivity. Citrinin as a toxic metabolite was measured from the Monascus fermentation broth. The biopigment productions were detected from fermentation broth by scanning spectra of each strain produced. Results showed a mixture of yellow, orange and red pigments with absorption peaks of pigments occurring at different wavelengths for the four strains. It was found that for each pigment color, the color production from the strains increased in the order TISTR 3002, 3180, 3090, 3385 with 3385 production being approximately 10 times that of 3002. Similar results were found for growth kinetics and productivity. HPLC results showed that citrinin was not produced under the culture conditions of this study. The L*, a* and b* values of the CIELAB color system were also obtained for the yellow, orange and red pigments produced from the TISTR 3002, 3180, 3090 and 3385 strains. The colors of the pigments ranged from burnt umber to deep red.     

红曲霉菌液相培养高产色素低产桔霉素的代谢调控研究

从8株固态发酵高产红曲色素菌株中筛选出一株适合于液相培养工艺的高产红曲色素菌株FL1,并对其液相培养过程特性及高产色素低产桔霉素的代谢调控策略进行了研究.发酵过程动力学研究结果表明,红曲色素与桔霉素作为次级代谢产物,其合成与红曲霉菌生长的关系属于非生长偶联型.本文首次采用连续补料的Fed-Batch培养技术,用于红曲霉...