应用响应面法优化发酵培养基提高达托霉素产量

[背景]达托霉素来自玫瑰孢链霉菌NRRL 11379的发酵产物,是重要的临床用抗生素.其原始产生菌发酵周期长,影响达托霉素的生产效率.本实验室前期在天蓝色链霉菌中重构了达托霉素的生物合成途径,有效地缩短了发酵周期,但重组菌株K10中达托霉素发酵产量很低,制约了后续的研究和开发.[目的]利用响应面法优化产达托霉素的重组菌...     

响应面法优化复合益生菌固体发酵麸皮工艺

利用响应面法对复合益生菌发酵小麦麸皮生产多酚的工艺进行优化,为小麦麸皮发酵工业化生产提供参考。本试验采用Plackett-Burman设计法对影响麸皮发酵产生多酚的8个影响因子重要性进行考察,筛选出具有显著性影响的主效应因素,再通过最陡爬坡试验确定试验中心点,利用响应面分析法确定各显著影响因子的最佳水平。最终确定优化后的发酵工艺为:豆粕添加量为1%,糖蜜添加量为1%,NHS05接种量为7.5%,NHS03接种量为1%,NHS01接种量为1%,含水量为35.5%,培养温度为25℃,发酵时间为105.8 h。优化后复合益生菌发酵麸皮产生多酚产量从2.43 mg·g^-1增至4.54 mg·g^-1,提高了1.88倍。     

响应面分析法优化大豆肽发酵培养基

采用响应面分析法对大豆肽发酵培养基进行优化,首先采用二水平Plackett-Burman设计对影响大豆肽发酵的8个因素进行筛选,获得影响最大的3个因素为料水比、MgSO_4、糖蜜.再利用响应面分析法对这3个因素进行优化,确定最佳培养基条件为料水比为1∶1.149、MgSO_4浓度为0.048%、糖蜜浓度为0.294%,在此条件下,优化后的大豆肽含量为21.74%,试验值与模型预测值只有1.21%的误差.     

响应面法优化普鲁兰多糖发酵培养基

以出芽短梗霉IFO 4464为实验菌种,采用响应面法(RSM)优化了出芽短梗霉IFO 4464产普鲁兰多糖的发酵培养基。通过实验得到出芽短梗霉最佳发酵培养基为蔗糖59.8g/L,硫酸铵0.7 g/L,硫酸镁0.3 g/L,磷酸二氢钾5.0g/L,氯化钾0.5g/L,氯化钠1.5g/L,酵母浸膏2.5 g/L,多糖产量可达21.92 g/L。     

响应面法优化芽孢杆菌B-6产絮凝剂的发酵培养基

对芽孢杆菌B-6摇瓶发酵产生物絮凝剂的培养基进行优化研究.在单因素试验的基础上,通过Plackett-Burman设计对培养基的6个因素进行筛选,结果表明影响显著的3个因素为:硝酸钠、磷酸氢二钾、吐温;然后用最陡爬坡路径逼近最大响应区域,最后通过Box-Behnken设计和响应面分析得出芽孢杆菌B-6产生物絮凝剂的最佳发酵培养基为:蔗糖2.5%、酵母膏0.05%、尿素0.02%、硝酸钠0.033%、磷酸氢二钾0.515%、硫酸镁0.02%、氯化钠0.15%、吐温-20 0.16%.     

响应面法优化蝙蝠蛾拟青霉发酵培养基配方

为了提高虫草无性型蝙蝠蛾拟青霉(Paecilomyces hepiali)菌丝体中的腺苷含量,采用响应面法对其液体发酵培养基配方进行了优化。首先采用Plackett-Burman设计法对影响蝙蝠蛾拟青霉腺苷收率的8个相关因素进行了筛选,从中确定其主要影响因子为马铃薯和蚕蛹粉。然后用最陡爬坡试验逼近上述2个因素的最大响应区域,并通过中心组合设计和响应面分析法,确定了主要影响因子的最佳浓度。优化后的培养基组成为:马铃薯8.25%,蔗糖1%,玉米粉1%,蛋白胨0.5%,蚕蛹粉0.81%,KH2PO40.1%,MgSO4.7H2O 0.1%,(NH4)2 SO40.1%。该配方所产生的蝙蝠蛾拟青霉菌丝体中腺苷含量由优化前的2.15 mg/g(干重)提高到3.44 mg/g(干重)。     

翅鳞伞培养条件响应面法优化研究

在Plackett Burman实验设计结果基础上 ,采用响应曲面法 (ResponseSurfaceMethodolo gy,RSM)对影响翅鳞伞 (Pholiotasquarrosa)AS 5.2 45发酵胞外多糖与菌丝生长的关键影响因子最佳水平范围进行了研究和探讨。通过对胞外多糖曲面方程以及菌丝干重二次多项回归方程求解得知 ,在自变量培养温度 ,培养时间和装液量分别为 28.07℃、8.79d和 68.51mL时 ,翅鳞伞胞外多糖的最大预测值为1062.69μg·mL 1发酵醪 ;27     

响应面方法优化菊粉酶液体发酵培养基的研究

目的：为提高菊粉酶的产量。方法：运用Plackett-Burman设计法和响应面分析法,对Kluyveromyces S120液体发酵生产菊粉酶的培养基进行了优化。首先通过Plackett-Burman方法对8个相关影响因素的效应进行评价,并筛选出了有显著正效应的菊芋粉、玉米浆、(NH_4)H_2PO_4等三个因素,其他五个因素没有显著影响。然后根据Box-Behnken的中心组合设计实验和响应面分析方法确定了上述三个主要影响因素的最佳浓度。结果：在优化培养基下,菊粉酶产量为102．82u/mL,是优化前的2．1倍。     

海金沙草总黄酮提取工艺的响应面优化

为了提高海金沙草总黄酮提取效率,运用了Plackett-Burman试验设计、爬陡坡试验和Box-Behnken设计对提取工艺进行了响应面优化试验。利用Plackett-Burman对影响总黄酮提取的诸多相关因素进行了评价并成功筛选出主效应因子,即提取时间、提取温度和乙醇浓度。在Plackett-Burman设计基础上,根据主效应因子作用大小与方向进行了爬陡坡试验。最后用Box-Behnken响应面技术优化了总黄酮提取工艺并建立了关键影响产量的二次多项式数学模型,解模型逆矩阵得最优解(优化方案),即提取温度X1=45.45℃,乙醇体积分数X2=47.1%、提取时间X3=84.8 min。模型预测结果为0.433 mg.L-1,验证试验结果为0.428±0.004 mg.L-1(n=3)。     

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%。     

基于响应面法对香菇原生质体制备条件的优化

香菇Lentinula edodes是我国食用菌年产量最大的单品,优化香菇原生质体的制备条件,获得高质量、高活力的原生质体可以为香菇育种和遗传多样性分析提供技术保障。本研究利用单因素试验对稳渗剂浓度、酶解液类型、酶解时间、酶解温度4个因素的最优作用条件和相关性进行检验和筛选;依据单因素试验的结果,对酶解时间、酶解温度、酶解液种类进行响应面法3因素3水平试验优化分析。单因素试验结果表明,使用2%的溶壁酶+蜗牛酶+纤维素酶混合酶制剂为酶解液、0.6mol/L甘露醇为稳渗剂的效果显著高于其他处理(P<0.05)。经Box-Behnken设计得出香菇原生质体最佳制备条件为酶解时间3.25h,酶解液浓度1.7%,酶解温度30.49℃,获得原生质体产量为14.02×10⁶ CFU/mL,与理论产量(13.862×10⁶ CFU/mL)偏差小,可为后续原生质体融合育种和多样性分析提供重要基础。     

响应面法优化耐高温酵母生产高浓度乙醇

利用耐高温酵母GXASY-10菌株对木薯粉同步糖化(SSF)法生产高浓度乙醇的发酵条件进行了优化。在单因素实验的基础上,首先应用Plackett-Burman试验设计筛选影响酒精高温高浓度发酵的重要参数,采用最陡爬坡实验逼近最大酒精生产区域后,利用Box-Behnken设计确定重要参数的最佳水平。筛选结果表明,影响酒精产量的重要参数是液化时间、糖化酶用量和初始木薯粉(底物)浓度。最佳工艺条件为:液化时间为35min,糖化酶添加量为1.21AGU/g底物,底物浓度为37.62%。20L发酵罐在此条件下(发酵温度37℃,转速100r/min)经过48h发酵,酒精浓度可达16.07%(V/W)。优化条件与初始条件相比较,酒精浓度提高了33%。     

响应曲面法优化灵芝廉价型深层发酵培养基的研究

为了获得生产用廉价型灵芝发酵培养基,采用中心组合旋转设计法和响应曲面法对低成本培养基组分进行了优化。优化的四个组分为玉米粉(x1)、麸皮粉(x2)、豆饼粉(x3)和蔗糖(x4)。结果表明,灵芝菌体发酵和多糖发酵的培养基预测模型分别为:Y1=15.1–0.31x1–0.34x2+0.36x3–0.44x4–1.26x12–1.98x22–0.85x32–1.15x42–0.59x2x3和Y2=2.0–0.08x1–0.08x2+0.04x3–0.09x4–1.13x12–0.33x22–0.08x32–0.16x42–0.16x2x3–0.10x1x4。从中获得菌体发酵的最优配方为:玉米粉19.7g/L,麸皮粉11.3g/L,豆饼粉6.3g/L,蔗糖19.5g/L;多糖发酵的最优配方为:玉米粉19.6g/L,麸皮粉11.0g/L,豆饼粉6.7g/L,蔗糖19.1g/L。150L发酵罐中试放大结果表明,灵芝菌体的产量为16.92g/L,多糖产量为1.86g/L。所得培养基为灵芝产品的高效低成本生产提供了基础。     

Optimization of a culture medium for xylanase production by Bacillus sp. using statistical experimental designs

The concentrations of oat spelt xylan, casein hydrolysate and NH4Cl in the culture medium for production of xylanase from Bacillus sp. I-1018 were optimized by means of response surface methods. The path of steepest ascent was used to approach the optimal region of the medium composition. The optimum composition of the nutrient medium was then easily determined by using a central composite design and was found to be 3.16g/l of xylan, 1.94g/l casein hydrolysate, 0.8g/l of NH4Cl. The xylanase production was increased by 135% when the strain was grown in the optimized medium compared to initial medium.     

Determination of an economical medium for growth of Lactobacillus fermentum using response surface methodology

Aim: Lactobacillus fermentum is a widely utilized probiotic compound fed as an alternative to antibiotics for growth promotion in a wide variety of livestock species. The objective of this research is to develop an economical and practical fermentation medium for the growth of Lact. fermentum using response surface methodology. Methods and Results: A two‐level Plackett–Burman design was used to determine which factors in the fermentation medium influence the growth of Lact. fermentum. Under our experimental conditions, peptone, urea and yeast extract were found to be major factors. Then, the steepest ascent method and the central composite design were applied to optimize the culture of Lact. fermentum. The following composition of the fermentation medium was estimated to be the most economical formula (per litre): 30 g corn syrup, 15 g glucose, 14·4 g peptone, 7 g (NH₄)₂SO₄, 0·5 g urea, 3 g sodium acetate, 4 g sodium citrate, 0·1 g MnSO₄·4H₂O, 0·5 g MgSO₄·7H₂O, 7·3 g yeast extract, 0·5 g K₂HPO₄. Conclusion: Based on 10 side‐by‐side comparisons, we found that the yield of Lact. fermentum using our fermentation medium was 64% greater than those using modified de Man, Rogosa and Sharp broth (MRS) medium (1·8 × 10⁹ CFU ml^?1vs 1·1 × 10⁹ CFU ml^?1, respectively), while the cost was 89% lower than MRS. This research indicates that it is possible to increase bacterial yield by using inexpensive materials. Significance and Impact of the Study: It is more likely that the use of Lact. fermentum as a probiotic will increase. The low cost medium developed in this research can be used for large‐scale, commercial application where economics are quite likely to be important.     

Optimization of medium components for phytase production by E. coli using response surface methodology

The medium for recombinant phytase production by E. coli BL21 was optimized using response surface methodology. A 2³ central composite experimental design was used to study the combined effect of the medium components, tryptone, yeast extract and NaCl. Addition of 2?g/l glucose to the medium greatly influenced the phytase production. The optimization of the medium has increased the phytase production by 1.2 times. The incorporation of 2?g/l glucose significantly enhanced the phytase production by 1.58 times, showing an overall 2.78 fold increase before optimization and other modifications of the medium. The optimized medium with glucose showed a highest phytase activity of 2250?U/l.     

响应面法优化黑曲霉产异淀粉酶的培养条件

在液态发酵条件下,采用单因素实验确定了Aspergillus niger PZ331产异淀粉酶的最适碳源和氮源,分别为蔗糖和硝酸铵。在上述基础上利用Plackett-Burman设计对影响产异淀粉酶的因素进行评价,并筛选出硝酸铵、接种量、培养温度3个主要因素;继而利用响应面设计优化了最佳硝酸铵浓度、接种量和培养温度。最终确定了最优培养条件为：蔗糖10 g/L,硝酸铵10 g/L,磷酸氢二钾3 g/L,硫酸亚铁0.01 g/L,硫酸镁1 g/L,起始p H值4.2;接种量2%（孢子浓度为107cfu/m L）,30℃培养72 h,酶活达137.3μ/m L;比基础培养基的提高了1.71倍左右。