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1.
大孢虫花菌丝体多糖提取工艺优化及其测定方法优选   总被引:3,自引:0,他引:3  
刘桂君  文华安 《菌物学报》2006,25(4):624-632
通过采用3,5-二硝基水杨酸法、蒽酮-硫酸法和苯酚-硫酸法测定大孢虫花PaecilomycestenuipesPeck菌丝体多糖含量,比较精密度、样品回收率、稳定性三个指标,得出最佳测定方法为蒽酮-硫酸法。根据一次一因素实验和Box-Behnken中心组合实验,应用SAS软件分析得出大孢虫花菌丝体多糖提取的最佳条件为:100℃沸水浴,提取2h,重复4次,料液比(菌丝体质量:蒸馏水体积)为1︰20,此条件下大孢虫花菌丝体多糖为4.12g/100g。  相似文献   
2.
细菌纤维素发酵培养基的优化及超微观结构分析   总被引:1,自引:0,他引:1  
为了提高细菌纤维素的产量, 本研究对一株氧化葡糖杆菌菌株J2液体发酵生产细菌纤维素的培养基进行了优化, 并对其代谢的细菌纤维的超微观结构进行了观察。运用Plackett-Burman试验设计法对8个相关影响因素的效应进行了评价, 筛选出了有显著效应的3个因素: 酵母膏、ZnSO4、无水乙醇, 其他5个因素的影响未达到显著水平(P>0.05)。然后采用Box-Behnken的中心组合试验设计和响应面分析方法(RSM)确定了上述三个因素的最佳浓度, 并且以棉纤维为对照, 运用扫描电镜观察了细菌纤维素的超微观结构, 结果表明: 菌株J2利用优化后的发酵培养基生产细菌纤维素的产量为11.52 g/100 mL, 是优化前的1.35倍, 电镜照片显示细菌纤维素微纤维丝直径<0.1 mm, 比棉纤维细很多, NaOH处理可以除去纤维网络结构中的菌体。  相似文献   
3.
采用乙醇-酶预处理体系,结合水提法较系统地研究了灵芝子实体中β-葡聚糖的提取技术。结果表明,乙醇-酶体系预处理的关键参数为:乙醇质量分数60%(V/V),加酶量1.5%(M/V,g/m L)、酶解温度45℃、酶解p H8.0;在乙醇-酶体系预处理的基础上,进一步采用单因素试验和Box-Benhnken试验设计与响应面分析法对灵芝子实体中β-葡聚糖的热水提取工艺进行了优化。结果显示水提温度、提取时间、水料比3个因素及水提温度与水料比二者的交互作用对β-葡聚糖的提取有显著影响。经优化后获得3个核心因素的最佳水平为:提取温度80℃、提取时间2.5h、水料比35:1。在乙醇-酶预处理结合水提取条件下,灵芝子实体中β-葡聚糖的提取得率可达0.412mg/g,是传统无水乙醇回流预处理结合水提法提取β-葡聚糖得率的2.1倍。本研究为灵芝β-葡聚糖的进一步提取放大试验奠定了技术基础。  相似文献   
4.
【目的】【方法】采用Box-Behnken法设计三因素三水平响应面实验,对比分析了高温蛋白酶高产菌株枯草芽孢杆菌BY25发酵过程中细菌生长与产酶之间的关系。【结果】实验表明,细菌生长与产酶的关系在各因素交互影响下变化显著。在中低水平的有机氮源添加条件下,细菌的大量繁殖显著抑制了蛋白酶产量,而在高水平的有机氮源添加条件下,细菌量的增长对产酶的作用由抑制转为促进。【结论】该结果表明,产酶诱导物有机氮源豆制品废渣的添加很可能显著提高了枯草芽孢杆菌群体中产酶菌的比率,而在没有合适诱导物的情况下通过增加细菌量并不能有效提高蛋白酶产量。  相似文献   
5.
Quantifying and optimizing the polyphenol content of Phyllanthus maderaspatensis was accomplished using a single-solvent HPTLC system. Analyzing hydroalcoholic extracts for kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, we simultaneously quantified and optimized their concentration. In the experiment, the methanol to water ratio (%), temperature (°C), and time of extraction (min) were all optimized using a Box-Behnken statistical design. Kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid were among the dependent variables analyzed. In the HPTLC separation, silica gel 60F254 plates were used, and toluene, ethyl acetate, and formic acid (5:4:1) made up the mobile phase. For kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, densitometric measurements were carried out using the absorbance mode at 254 nm. Hydroalcoholic extract of P. maderaspatensis contains rutin (0.344), catechin (2.62), gallic acid (0.93), ellagic acid (0.172), quercetin (0.0108) and kaempferol (0.06). Further, it may be affected by more than one factor at a time, resulting in a varying degree of reaction. A negative correlation was found between X1 (extraction time (min)) and X2 (temperature), as well as X1 and X3 (solvent ratios). Taking these characteristics into consideration, the method outlined here is a validated HPTLC method for measuring kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid.  相似文献   
6.
利用逐因子试验和Box-Behnken试验对黑豆皮中红色色素萃取工艺进行了优化研究,获得了工艺优化的数学模型y=3.85+0.43x1+0.05x2-0.32x3-0.12x1x2+0.063x1x3+1.0E-0.02x2x3-0.58x12-0.49x22-0.34x32,分别对自变量求偏导得到优化工艺条件:x1=0.346,x2=0.006988,x3=-0.44,通过转换得到实际工艺条件,即萃取温度X1=83.46℃、萃取时间X2=30.07 m in、料液比X3=1:35.6(w/v)。在最优化条件下模型预测OD512为3.997,验证试验结果为3.85±0.01(n=3),试验证明,逐因子试验和Box-Behnken试验联用可以很好的应用于黑豆皮红色色素的萃取工艺中。  相似文献   
7.
The application of biological processes in restoring oil polluted sites is growing due to their efficiency in removing different classes of pollutants. The aim of this study was to determine the ability of microorganisms present in a drilling-waste polluted soil (36,200 mg TPH kg?1 soil) to remove weathered hydrocarbons under stimulated and non-stimulated soil conditions. The hypothesis under study was whether petroleum hydrocarbons removal could be enhanced by manipulating C/N ratio, water content and addition of three agroindustrial wastes. A Box-Behnken design was employed to evaluate the effect of each variable. Results demonstrated that, for orange peels and banana trunk treatments, the variable with the largest effect (p < 0.01) on hydrocarbon removal was the C/N ratio, indicating that higher ratio (100/3) improved removal (79.5–82%). The largest effect (p < 0.001) on hydrocarbon removal for pineapple wastes was observed with higher water content (60%) achieving the highest removal (89%). After 90 days of experimentation, the type of agricultural waste and the agricultural waste/soil ratio were not statistically significant in any treatment. However, their addition was important relative to non-stimulated soil, which showed a hydrocarbon removal of 17%. Data reported in this study showed the application of bioremediation in clay and drilling waste-polluted soils.  相似文献   
8.
微波辅助提取木豆根中染料木素工艺   总被引:1,自引:1,他引:0  
以木豆根为原料,利用微波辅助提取技术进行提取,在单因素实验的基础上对提取条件进行了考察,根据BBD(Box-Behnken design)实验设计原理,采用3因素3水平的响应面分析法,以木豆根中主要异黄酮染料木素(genistein)为指标,对提取过程进行优化,得到最佳工艺参数为:提取温度为68℃,固液比为32∶1 mL·g-1,乙醇浓度为78%,提取功率700 W,提取时间15 min。在最佳提取条件下染料木素的提取率可达到0.465±0.032 mg·g-1。本研究对于微波提取技术的应用及木豆根的开发和利用都具有显著的意义。  相似文献   
9.
Thermostable lipase production by Geobacillus thermoleovorans was optimized in shake-flask cultures using Box-Behnken experimental design. An empirical model was developed through response surface methodology to describe the relationship between tested variables (Tween 80, olive oil, temperature and pH) and enzyme activity. Maximum enzyme activity (495 U l–1) was attained with Tween 80 at 5 g l–1; olive oil at 60 g l–1; 70 °C and pH 9. Experimental verification of the model showed a validation of 95%, which is more than 4-fold increase compared to the basal medium.  相似文献   
10.
Quantifying and optimizing the polyphenol content of Phyllanthus maderaspatensis was accomplished using a single-solvent HPTLC system. Analyzing hydroalcoholic extracts for kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, we simultaneously quantified and optimized their concentration. In the experiment, the methanol to water ratio (%), temperature (°C), and time of extraction (min) were all optimized using a Box-Behnken statistical design. Kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid were among the dependent variables analyzed. In the HPTLC separation, silica gel 60F254 plates were used, and toluene, ethyl acetate, and formic acid (5:4:1) made up the mobile phase. For kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, densitometric measurements were carried out using the absorbance mode at 254 nm. Hydroalcoholic extract of P. maderaspatensis contains rutin (0.344), catechin (2.62), gallic acid (0.93), ellagic acid (0.172), quercetin (0.0108) and kaempferol (0.06). Further, it may be affected by more than one factor at a time, resulting in a varying degree of reaction. A negative correlation was found between X1 (extraction time (min)) and X2 (temperature), as well as X1 and X3 (solvent ratios). Taking these characteristics into consideration, the method outlined here is a validated HPTLC method for measuring kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid.  相似文献   
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