Optimization of fermentation parameters in phage production using response surface methodology

Previously, we used computer-controlled fermentation technology to improve the yield of filamentous phage produced in Escherichia coli by 10-fold (Grieco et?al., Bioprocess Biosyst Eng 32:773-779, 2009). In the current study, three major fermentation parameters (temperature, dissolved oxygen [DO], and pH) were investigated using design of experiments (DOE) methodology. Response surface methodology (RSM) was employed to create a process model and determine the optimal conditions for maximal phage production. The experimental data fitted best to a quadratic model (p?相似文献   

Optimization of microbiological parameters for enhanced griseofulvin production using response surface methodology

Central composite design was used to determine the optimal levels of microbiological parameters, viz., slant age, seed age and inoculum level, for enhanced griseofulvin production by Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvum MTCC 2004 in shake flask fermentation. The optimal levels of slant age, seed age and inoculum level for Penicillium griseofulvum MTCC 1898 were found to be 8.8772 days, 4.2093 days, 12% (v/v) (᷁.56 kg dry cell mass/m³) and for Penicillium griseofulvum MTCC 2004, 8.221 days, 3.4875 days and 9% (v/v) (̀.09 kg dry cell mass/m³) respectively. The yield of griseofulvin under optimal conditions was found to be 1.65 times for Penicillium griseofulvum MTCC 1898 and 1.07 times for Penicillium griseofulvum MTCC 2004 higher than that obtained using unoptimized conditions. The fermentation time for maximum production of griseofulvin by Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvum MTCC 2004 decreased by 4 days and 2 days respectively.     

响应面法优化荷叶离褶伞菌丝体产漆酶条件

为了对荷叶离褶伞产漆酶条件进行优化,在单因素实验基础上,通过最陡爬坡实验(PB)对培养基8因素进行筛选,获得影响产漆酶的3个显著性因素:葡萄糖,pH和KH₂PO₄;通过中心组合(CCD)设计及响应面分析确定了最优发酵条件:葡萄糖20.09g/L,酪蛋白1.5g/L,酵母提取物1.5g/L,MgSO₄ 3g/L,CuSO₄ 3.75mg/L,KH₂PO₄ 3.97g/L,pH 4.98,VB₁ 0.1g/L,愈创木酚12mg/L,该条件下,漆酶酶活为829.83U/mL,较未优化对照提高46.6%.     

Optimization of fermentation medium for amidase production by response surface methodology

采用响应面分析方法,对阿萨希丝孢酵母(Trichosporon asahii)ZZB-1产酰胺酶的发酵培养基进行了优化.运用单因子试验筛选出麦芽糖和酵母浸膏为最适碳源、氮源,金属离子Ca2+、Mn2+可提高发酵酰胺酶产量;通过最陡爬坡实验逼近以上4个因子的最大响应区域后,采用Box-Behnken响应面分析法,确定产酰胺酶最佳发酵培养基为麦芽糖18.84 g/L、酵母浸膏9.55 g/L、NaCl 5g/L、KH2 PO41g/L、MgSO4·7H2O 0.2 g/L、FeSO40.001g/L、CaCO370.84 μmol/L、MnSO4 65.39 μmol/L(1％丙烯酸诱导),NH4·H2O调节pH至7.0.培养基优化后酰胺酶产量由初始2554U/L提高到4156 U/L,为原始发酵培养基配方酶活产量的1.63倍.     

响应面法优化产酰胺酶发酵培养基

采用响应面分析方法,对阿萨希丝孢酵母（Trichosporon asahii）ZZB-1产酰胺酶的发酵培养基进行了优化。运用单N子试验筛选出麦芽糖和酵母浸膏为最适碳源、氮源,金属离子Ca^2＋、Mn^2＋可提高发酵酰胺酶产量;通过最陡爬坡实验逼近以上4个因子的最大响应区域后,采用Box—Behnken响应面分析法,确定产酰胺酶最佳发酵培养基为麦芽糖18．84g／L、酵母浸膏9．55g／L、NaC15g／L、KH2PO41g／L、MgSO4·7H2O0．2g／L、FeS040．001g／L、CaC0370．84μmol／L、MnS0465．39肚mo[／L（1％丙烯酸诱导）,NH4·H2O调节pH至7．0。培养基优化后酰胺酶产量由初始2554U／L提高到4156U／L,为原始发酵培养基配方酶活产量的1．63倍。     

Optimization of mycophenolic acid production in solid state fermentation using response surface methodology

Mycophenolic acid (MPA) can be produced in solid state fermentation. An isolate of Penicillium brevi-compactum ATCC 16024 grown on moist wheat bran produced a titre of 425 mg per kg of wheat bran. Central composite rotatable design and response surface methodology were employed to derive a statistical model for media optimization towards production of mycophenolic acid. Five levels with a five factorial design were adopted. The correlation coefficient was 0.82, ensuring a satisfactory adjustment of the model to the experimental values. This statistical design was very effective in improving the titre of mycophenolic acid up to 3286 mg per kg of wheat bran. Received 24 July 1998/ Accepted in revised form 4 December 1998     

Optimization of fermentation conditions for the production of ethanol from sago starch using response surface methodology

The quantitative effects of temperature, pH and time of fermentation were investigated on simultaneous saccharification and fermentation (SSF) of ethanol from sago starch with glucoamylase (AMG) and Zymomonas mobilis ZM4 using a Box–Wilson central composite design protocol. The SSF process was studied using free enzyme and free cells and it was found that with sago starch, maximum ethanol concentration of 70.68 g/l was obtained using a starch concentration of 140 g/l, which represents an ethanol yield of 97.08%. The optimum conditions for the above yield were found to be a temperature of 36.74 °C, pH of 5.02 and time of fermentation of 17 h. Thus by using the central composite design, it is possible to determine the accurate values of the fermentation parameters where maximum production of ethanol occurs.     

Optimization of docosahexaenoic acid production by Schizochytrium limacinum SR21

Culture conditions of Schizochytrium limacinum SR21 for the purpose of microbial docosahexaenoic acid (DHA) production were investigated. The strain SR21 showed a wide tolerance to salinity; that is, the optimum salinity was between 50% and 200% that of sea water. Monosaccharides (glucose and fructose) and glycerol supported good cell growth and DHA yield. Di- and polysaccharides, oleic acid, and linseed oil gave low DHA yields. A high content of DHA (more than 30% of total fatty acids) was obtained from culture on glucose, fructose, and glycerol, and also the strain had simple polyunsaturated fatty acid profiles. The major polyunsaturated fatty acids other than DHA were n-6 docosapentaenoic acid only, and the contents of icosapentaenoic acid and arachidonic acid were less than 1%. Using corn steep liquor as a nitrogen source, a high total fatty acid content was obtained. The total fatty acid content in the dry cell weight increased as the concentration of the nitrogen source decreased, reached more than 50%. An increase in carbon source concentration led to a high DHA yield. A maximum DHA yield of more than 4 g/l was obtained in both glucose and glycerol media at 9% and 12% respectively. S. limacinum SR21 was thought to be a promising resource for microbial DHA production yielding a good level of productivity as well as a simple polyunsaturated fatty acid profile. Received: 26 June 1997 / Received revision: 29 August 1997  / Accepted: 19 September 1997     

裂殖壶菌发酵产DHA过程呼吸参数的在线检测分析

利用尾气分析仪对发酵过程的尾气中的O2、CO2含量进行实时检测,建立了裂殖弧菌发酵生产DHA过程中的呼吸参数在线检测方法,实现了裂殖壶菌补料分批发酵过程及双阶段供氧控制发酵过程中的呼吸参数在线检测分析。通过呼吸参数在线检测分析,从氧消耗机制方面解释了双阶段氧传递控制工艺能获得较高生物量、油脂和DHA含量的原因,从而为该工艺过程提供了理论指导。根据发酵过程中菌体生长不同时期的呼吸参数的变化情况,建立了基于呼吸商变化的在线补料控制方法,设计了一种基于RQ-Stat的补料工艺。RQ-Stat补料方式最终获得的油脂含量、DHA产量和产率比间歇式补料工艺分别提高了11.58%、12.19%和11.40%。     

Optimization of culture conditions for production of yeast biomass using bamboo wastewater by response surface methodology

Response surface methodology (RSM) was applied to optimize culture conditions for the growth of Candida utilis with bamboo wastewater. A significant influence of initial pH, fermentation time and yeast extract on biomass of C. utilis was evaluated by Plackett–Burman design (PBD). These factors were further optimized using a central composite design (CCD) and RSM. A combination of initial pH 6.1, fermentation time 69 h and yeast extract 1.17 g/L was optimum for maximum biomass of C. utilis. A 1.7-fold enhancement of biomass of C. utilis was gained after optimization in shake-flask cultivation. The biomass of C. utilis reached 19.17 g/L in 3 L fermentor.     

Box-Behnken响应面法优化司替霉素B产生菌发酵条件

【背景】粗糙链霉菌(Streptomyces scabrisporus) HBERC-53204是本中心自主分离的一株链霉菌,经鉴定,其产生一种活性化合物司替霉素B (steffimycin B,SMB),对多种动植物重要病原菌具有良好生物活性。【目的】提高SMB发酵水平,拓宽放线菌活性天然产物在农牧业领域的研究及应用。【方法】以本实验室筛选出的一株产SMB的粗糙链霉菌HBERC-53204为研究对象,运用单因素试验筛选培养基的主效碳源、氮源、无机盐及各营养成分最适浓度,并基于单因素试验结果,通过Plackett-Burman(PB)试验设计筛选出显著影响因素,再结合最陡爬坡试验、Box-Behnken (BB)响应面法拟合显著因子与产量的非线性方程求解,进一步优化菌株产SMB的最佳发酵培养基配方。【结果】优化后最佳培养基配方为：葡萄糖36.22 g/L,蛋白胨8.00 g/L,酵母粉8.51 g/L,酸水解酪蛋白1.50 g/L,MgSO₄ 0.68 g/L,KNO₃ 1.00 g/L。经摇瓶验证,优化后SMB效价达到477.26 mg/L...     

Solid-state fermentation for xylanase production by Thermoascus aurantiacus using response surface methodology

We investigated xylanase production by Thermoascus aurantiacus using semisolid fermentation. Multivariant statistical approaches were employed to evaluate the effects of several variables (initial moisture in the medium, cultivation time, inoculum level, and bagasse mass) on xylanase production. The initial moisture content and bagasse mass were the most important factors affecting xylanase activity. The xylanase activity produced by the fungus under the optimized conditions (81% moisture content and 17 g bagasse) was found to be 2700 U per gram of initial dry matter, whereas its value predicted by a polynomial model was 2400 U per gram of initial dry matter. Received: 4 December 1998 / Received revision: 15 March 1999 / Accepted: 16 May 1999     

Optimization of fermentation conditions for production of anti-TMV extracellular ribonuclease by Bacillus cereus using response surface methodology

Bacillus cereus ZH14 was previously found to produce a new type of antiviral ribonuclease, which was secreted into medium and active against tobacco mosaic virus. In order to enhance the ribonuclease production, in this study the optimization of culture conditions using response surface methodology was done. The fermentation variables including culture temperature, initial pH, inoculum size, sucrose, yeast extract, MgSO₄·7H₂O, and KNO₃ were considered for selection of significant ones by using the Plackett–Burman design, and four significant variables (sucrose, yeast extract, MgSO₄·7H₂O, and KNO₃) were further optimized by a 2⁴ factorial central composite design. The optimal combination of the medium constituents for maximum ribonuclease production was determined as 8.50 g/l sucrose, 9.30 g/l yeast extract, 2.00 g/l MgSO₄·7H₂O, and 0.62 g/l KNO₃. The enzyme activity was increased by 60%. This study will be helpful to the future commercial development of the new bacteria-based antiviral ribonuclease fermentation process.     

产S-酰胺酶培养基统计学筛选与响应面优化

利用Design Expert软件中的两水平实验设计和响应面法,对发酵生产S-酰胺酶(可用于拆分2,2-二甲基环丙甲酰胺外消旋体)的培养基进行了优化。采用Plackett-Burman(PB)设计对培养基中相关影响因素的效应进行评价并筛选出了有显著效应的葡萄糖、酵母粉及2,2-二甲基环丙甲酰胺浓度,其他因素对酰胺酶产量的影响不显著。然后用旋转中心组和实验设计及响应面分析确定了主要影响因素的最佳条件,在优化的培养基中,酰胺酶产量达到168 U/L,比优化前的80 U/L提高了110.0%。     

Optimization of medium constituents and fermentation conditions for the production of ethanol from palmyra jaggery using response surface methodology

The quantitative effects of sugar concentration, nitrogen concentration, EDTA, temperature, pH and time of fermentation on ethanol production were optimized using a Box-Wilson central composite design (CCD) experiment. It was found that palmyra jaggery (sugar syrup from the palmyra palm) is a suitable substrate for the production of high concentrations of ethanol using Saccharomyces cerevisiae NCIM 3090 by submerged fermentation. A maximum ethanol concentration of 129.4 g/l was obtained after optimizing media components and conditions of fermentation. The optimum values were a temperature of 26.2 °C, pH of 8.4, time of fermentation of 4.2 days with 398.5 g of substrate/l, 3.1 g of urea/l and 0.51 g of EDTA/l. Thus by using the CCD, it is possible to determine the accurate values of the fermentation parameters where maximum production of ethanol occurs.     

响应面法对微拟球藻产微藻蛋白的发酵条件优化

以稳定期微藻蛋白浓度为评价指标,利用响应面设计对微拟球藻(Nannochloropsis gaditana)的分批发酵条件进行优化。在单因素试验的基础上,选取温度、p H、搅拌速度及通气量为影响因子,采用四因素三水平的Box-Benhnken中心组合法设计试验。结果表明:微拟球藻的最佳发酵条件为温度30℃、p H 6.9、搅拌速度340 r/min以及通气量0.65 vvm,在此优化条件下得到微藻蛋白浓度为6.18 g/L,与模型预测值基本相符,较优化前提高了9.18%。     

响应面法优化松茸发酵产多糖的培养条件

运用响应面法对松茸产多糖的发酵培养条件进行优化研究。首先根据C、N源实验结果,利用Plackett-Bur-man设计,对影响多糖产量的相关因素进行评估,筛选出具有显著效应的3个因素:玉米粉、豆粕和KH2PO4。在此基础上,利用最陡爬坡试验逼近以上3个因素的最大响应区域,采用Box-Behnken设计法对各因素的水平组合进行优化,获得松茸产多糖优化发酵的培养条件:玉米粉质量分数4.54%,豆粕质量分数4.96%,KH2PO4质量分数0.15%,MgSO4.7H2O质量分数0.05%,VB1质量分数0.001%,初始pH5.5,摇床转速180 r/min,发酵时间10 d。在此优化培养条件下松茸总多糖产量可达5.97 g/L。     

Optimization of fermentation condition for antibiotic production by Xenorhabdus nematophila with response surface methodology

Aims: To evaluate the influence of environmental parameters on the production of antibiotics (xenocoumacins and nematophin) by Xenorhabdus nematophila and enhance the antibiotic activity. Methods and Results: Response surface methodology (RSM) was employed to study the effects of five parameters (the initial pH, medium volume in flask, rotary speed, temperature and inoculation volume) on the production of antibiotics in flask cultures by X. nematophila YL001. A 2^5?1‐factorial central composite design was chosen to explain the combined effects of the five parameters and to design a minimum number of experiments. The experimental results and software‐predicted values of production of antibiotics were comparable. The statistical analysis of the results showed that, in the range studied, medium volume in flask, rotary speed, temperature and inoculation volume had a significant effect (P < 0·05) on the production of antibiotics at their individual level, medium volume in flask and rotary speed showed a significant influence at interactive level and were most significant at individual level. The maximum antibiotic activity was achieved at the initial pH 7·64, medium volume in 250 ml flask 25 ml, rotary speed of 220 rev min^?1, temperature 27·8°C and inoculation volume of 15·0%. Maximum antibiotic activity of 331·7 U ml^?1 was achieved under the optimized condition. Conclusions: As far as known, there are no reports of production of antibiotic from X. nematophila by engineering the condition of fermentation using RSM. The results strongly support the use of RSM for fermentation condition optimization. The optimization of the environmental parameters resulted not only in a 43·4% higher antibiotic activity than unoptimized conditions but also in a reduced amount of the experiments. The chosen method of optimization of fermentation condition was efficient, relatively simple and time and material saving. Significance and Impact of the Study: This study should contribute towards improving the antibiotics activity of X. nematophila. Integrated into a broader study of the impact of environmental factors on the production of antibiotic, this work should help to build more rational control strategy, possibly involving scale‐up of production of antibiotics by X. nematophila.     

Optimization of methane fermentation from effluent of bio-hydrogen fermentation process using response surface methodology

The individual effects and interactive effects of substrate concentration, ratio of inoculum to substrate, Ca(2+) concentration on the methane yield from the effluent of bio-hydrogen fermentation of food waste were investigated in this study. A central composite design (CCD) and response methodology (RSM) were employed in designing the experiments, in order to determine the optimum conditions for methane fermentation. The experiment results showed that the effects of substrate concentration, ratio of inoculum to substrate, Ca(2+) concentration were statistically significant at 5% level. The interactive effect of substrate concentration and ratio of inoculum to substrate was significant, however the interactive effect of substrate concentration and Ca(2+) concentration, ratio of inoculum to substrate and Ca(2+) concentration were found to be insignificant at 5% level. A maximum yield of 565.76 ml CH(4)/g VS(added) was estimated under the optimum conditions for substrate concentration 7.77 g of VS/l, inoculum to substrate ratio of 2.81 and calcium concentration of 380.82 mg/l. Verification experiment of the estimated optimum conditions confirmed that the RSM was useful for optimizing the methane yield from effluent of bio-hydrogen fermentation of food waste.