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The production of dye-decolorizing peroxidase (DyP) was investigated by cultivating Geotrichum candidum Dec1 using molasses as a carbon source. Molasses at concentrations greater than 10 g.l(-1) was found to increase the decolorization activity of the culture broth toward dye, reactive blue 5 mainly because the amount of enzyme produced was enhanced. However, complete inhibition of DyP activity by molasses was observed at the concentration of 20 g.l(-1), indicating that the inhibitory effect of molasses on the culture broth activity to decolorize the dye was involved. When the culture broth was diluted 25 times, the dye-decolorizing activity was 7 times as much as that of non-diluted culture broth. The molasses fractions separated by gel chromatography (300-400 ml and 400-500 ml fractions) completely inhibited the purified DyP. On the basis of these results, we propose a scheme to control both positive and negative effects of molasses on the dye decolorization process. 相似文献
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The productivity of a peroxidase (DyP) originating from Geotrichum candidum Dec 1 was enhanced in the solid-state culture using Aspergillus oryzae RD005. When the humidity, water content, and temperature were adjusted to 60%, 50% and 27°C, respectively, the productivity of DyP reached 5.3 g per kilogram wheat bran, which was used as the solid medium. The yield of 5.3 g per kg wheat bran corresponded to the yield of a 56 kg submerged culture. The productivity per gram carbon of the medium in the solid-state culture was 4.1-fold that in the submerged culture. 相似文献
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Recombinant Aspergillus oryzae expressing a dye-decolorizing peroxidase gene (dyp) was cultivated for repeated-batch production of recombinant dye-decolorizing peroxidase (rDyP) using maltose as a carbon source. High-level rDyP activity in limitation of carbon and nitrogen sources was maintained stably for 26 cycles of repeated 1-d batches of A. oryzae pellets without any additional pH control. Cultures maintained at 4 degrees C for 20 d resumed rDyP production following a single day of incubation. One liter filtrated crude rDyP containing 4600 U rDyP decolorized 5.07 g RBBR at the apparent decolorization rate of 17.7 mg l(-1) min(-1). 相似文献
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Effect of molasses supplementation on the production of lactating dairy cows fed diets based on alfalfa and corn silage 总被引:5,自引:0,他引:5
Adding sugar to the diet has been reported to improve production in dairy cows. In each of 2 trials, 48 lactating Holsteins (8 with ruminal cannulas) were fed covariate diets for 2 wk, blocked by days in milk into 12 groups of 4, and then randomly assigned to diets based on alfalfa silage containing 4 levels of dried molasses (trial 1) or liquid molasses (trial 2). In both studies, production data were collected for 8 wk, ruminal samples were taken in wk 4 and 8, and statistical models were used that included covariate means and block. In trial 1, experimental diets contained 18% CP and 0, 4, 8, or 12% dried molasses with 2.6, 4.2, 5.6, or 7.2% total sugar. With increasing sugar, there was a linear increase in dry matter intake (DMI), and digestibility of dry matter (DM) and organic matter (OM), but no effect on yield of milk or protein. This resulted in linear decreases in fat-corrected milk (FCM)/DMI and milk N/N-intake. There was a linear decrease in urinary N with increasing sugar, and quadratic effects on milk fat content, yield of fat and FCM, and ruminal ammonia. Mean optimum from these quadratic responses was 4.8% total sugar in these diets. In trial 2, experimental diets contained 15.6% crude protein (CP) and 0, 3, 6, or 9% liquid molasses with 2.6, 4.9, 7.4, or 10.0% total sugar, respectively. Again, there were linear declines in FCM/DMI and milk N/N-intake with increasing sugar, but quadratic responses for DMI, yield of milk, protein, and SNF, digestibility of neutral detergent fiber and acid detergent fiber, milk urea, urinary excretion of purine derivatives, and ruminal ammonia. Mean optimum from all quadratic responses in this trial was 6.3% total sugar. An estimate of an overall optimum, based on yield of fat and FCM (trial 1) and yield of milk, protein, and SNF (trial 2), was 5.0% total sugar, equivalent to adding 2.4% sugar to the basal diets. Feeding more than 6% total sugar appeared to depress production. 相似文献
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目的:以甘蔗糖蜜为原料,研制一款新型调味料酒。方法:采用单因素试验探究糖蜜发酵酒的最佳酒母醪配方,并以此配方用5 L发酵罐制备糖蜜发酵酒为酒基,采用正交试验优化活性炭最佳脱色工艺条件,再用单因素试验确定调味剂的最佳添加比例。结果:糖蜜发酵酒的最佳酒母醪配方为初糖质量浓度200 g/L、(NH4)2SO4添加量1.0 g/L、玉米浆添加量10 g/L、MgSO4添加量0.2 g/L、NaCl添加量0.5 g/L、KH2PO4添加量0.5 g/L、CaO添加量0.2 g/L;最佳脱色工艺条件为活性炭添加量2%,脱色时间30 min,脱色温度55 ℃;调味剂的最佳添加比例为食用盐1.5 g/100 mL,味精0.4 g/100 mL,混合香辛料0.06%。结论:利用甘蔗糖蜜酿造料酒工艺可行,制备的糖蜜料酒清亮透明,香气协调,口味鲜爽,其理化指标与微生物指标符合调味料酒行业标准(SB/T 10416—2007)对新型调味料酒的要求。 相似文献
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Effects of altering fermentation parameters on glycerol and bioethanol production from cane molasses
Cate N Munene Willem H Kampen Henry Njapau 《Journal of the science of food and agriculture》2002,82(3):309-314
Current bioethanol production processes do not produce more than approximately 13 g l?1 glycerol at a purity of 11% total solids in the fermented mash. Such quantities are not sufficiently high for economic exploitation unless very‐large‐capacity plants are involved. It was envisaged that the ratio of glycerol to bioethanol could be altered in favour of glycerol by adjusting such fermentation parameters as osmotic pressure (water activity), pH, temperature and yeast cell inoculum. At 39.9 ° brix, pH 8.7, 38 °C, 90.7 atm and 120 × 106 yeast cells ml?1, glycerol formation in fermented mash increased to 56 g l?1 at a purity of 14% total solids. The potential for high glycerol production, hence higher revenue, has been demonstrated. Adoption of this technology could have a significant positive economic impact on existing or new biomass‐to‐ethanol plants. © 2002 Society of Chemical Industry 相似文献
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采用分光光度法测定莴笋多酚氧化酶(PPO)和过氧化物酶(POD)的活性,研究酶的稳定性、温度、p H、底物浓度及几种抑制剂对其活性的影响,建立相应酶促动力学方程,利用正交实验探讨最佳抑制条件。结果表明,PPO和POD最适温度分别为50℃和40℃,最适p H分别为6.0和6.5,随温度不断升高,PPO和POD活性逐渐下降。动力学方程分别为V=342.566[S]/(5.9×10-3+[S])和V=3403.008[S]/(6.88×10-4+[S])。对PPO抑制强弱为:VC>L-Cys>Na HSO3>柠檬酸>EDTA>苯甲酸>琥珀酸,对POD抑制强弱为:EDTA>VC>L-Cys>柠檬酸>Na HSO3>琥珀酸>苯甲酸。正交实验表明,对PPO最佳抑制条件为:Na HSO39mmol/L、L-Cys 5mmol/L及VC5mmol/L。对POD最佳抑制条件为:VC0.2mmol/L、EDTA 0.2mmol/L及L-Cys 1.4mmol/L。 相似文献
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研究了经煮沸、活性炭、亚铁氰化钾、磷酸与硫酸预处理的糖蜜对黄曲霉生长与合成L-苹果酸的影响以及培养基中N源添加。以经各种预处理的糖蜜培养黄曲霉,其生物量大小分别是:硫酸法>磷酸法>亚铁氰化钾法>活性炭法>煮沸法。硫酸能有效除去糖蜜中影响菌体生长的胶体物质,用硫酸处理的糖蜜作培养基时,其菌体生长量比煮沸处理高25%。用硫酸与亚铁氰化钾联合处理,对L-苹果酸合成最有利,其产酸达到59.6g/L。糖蜜培养基需添加1g/L硫酸铵为N源,较适培养基配方(g/L)为:糖120,NH4(SO4)21,K2HPO40.15,KH2PO40.15,CaCO370,pH5.5。 相似文献
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Vesna M. Vu
urovi Vladimir S. Puka Uro D. Milji 《Journal of the Institute of Brewing》2019,125(1):134-142
The aim of this study was the investigation and comparison of the potential of sugar beet molasses and thick juice as raw materials for bioethanol production, as renewable and sustainable energy sources. Ethanol fermentation of a wide range of initial sugar concentrations (100–300 g/L) was performed using either free or immobilised Saccharomyces cerevisiae in calcium alginate beads in the absence of any added nutrients. In general, immobilised cells showed better fermentative performance, enhanced ethanol productivity, stability and cell viability compared with free cells, under the same fermentation conditions. The high concentration of non‐sugar components contained in molasses affected yeast fermentation performance and viability. Maximum ethanol concentration in fermented media of 84.6 and 109.5 g/L were obtained by immobilised cells for initial sugar concentrations of 200 and 250 g/L for molasses and thick juice, respectively. However, the highest ethanol yields of 31.7 L per 100 kg of molasses and 37.6 L per 100 kg of thick juice were obtained by immobilised cells at an initial sugar concentration of 175 g/L. In the high gravity fermentation process, thick juice resulted in a higher ethanol yield per mass of raw material compared with molasses. This study shows the advantage of immobilised yeast for the efficient production of high gravity bioethanol from thick juice, which was a more favourable raw material than molasses. © 2018 The Institute of Brewing & Distilling 相似文献
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利用耐高渗透压酵母以糖蜜为原料生产甘油 总被引:2,自引:0,他引:2
通过一般发酵法得到的乙醇产品在发酵醪中大致产生 13g/L甘油。这个产量不适宜开发利用 ,利用耐高渗透压酵母 (Hollandia、Fleischmann)通过调整发酵条件例如渗透压 (水的活度 )、pH、温度、酵母接种量生成甘油。结果表明 ,在发酵条件为 3 9 9°bx、pH8 7、3 8℃、接种量 12 0× 10 6 个 /mL ,甘油产量可提高到 5 6g/L。此技术的应用会给发酵法生产乙醇的工厂带来巨大的经济效益 相似文献
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细菌漆酶具有良好的热稳定性和抗碱性环境能力,在工业废水处理和染料脱色方面具有很大的潜力。通过研究短小芽孢杆菌W3菌株的CotA漆酶基因在大肠杆菌中重组表达的酶学性质,对其发酵培养基进行优化,以提高产量。利用分子手段实现CotA漆酶基因在大肠杆菌中的重组表达,并利用BP神经网络建模和萤火虫算法寻优对CotA漆酶发酵培养基进行优化,最后重组表达的CotA漆酶进行染料脱色研究。结果表明,重组菌株表达的CotA漆酶具有良好的热稳定性和耐碱能力,最适反应pH值为3.5,最适反应温度为80 ℃。重组CotA漆酶对底物ABTS具有良好的亲和能力,Km为0.247 mmol/L,Kcat为41.32 s -1。在适宜条件下的重组CotA漆酶的表达量为1 915.3 U/L,使用BP神经网络和萤火虫算法优化培养基获得最佳的发酵培养基配方为:蛋白胨1.16 g/dL、酵母粉0.428 g/dL、NaCl 1.06 g/dL、CuSO 4 0.274 mol/L和甘油(体积分数)0.931%。优化过的培养基产CotA漆酶酶活为3 088.68 U/L,相比未优化之前提高了61.26%。重组表达的CotA漆酶对孔雀石绿和酸性蓝129脱色效果明显,达到90%脱色率。短小芽孢杆菌W3来源的CotA漆酶具有良好的酶学性质和工业应用前景。利用BP神经网络偶联萤火虫算法寻优是CotA漆酶发酵培养基优化的有效手段。 相似文献