一种生产1,3-丙二醇的发醇液的固液分离方法

1,3-丙二醇(1,3-porpandiol,简写为1,3-PD)是一种重要的化工原料,它不仅是良好的溶剂、抗冻剂、保护剂,而且还可参与多种化学合成反应,利用1,3-PD生产的新型聚酯纤维具有优良的回弹性,染色性、抗污染性和生物降解性等优良品质,在服装、工程塑料、地毯等领域应用潜力巨大。

地衣酚法定量测定发酵液中D-核糖的研究

本文确定了地衣酚法定量测定发酵液中 D-核糖的最佳条件 :发酵液稀释液 3m l (控制 D-核糖量在 30～ 6 0 μg) ,0 .1% Fe Cl3浓盐酸溶液 3m l,1%地衣酚乙醇溶液 0 .3ml,沸水中水浴显色 40 m in,水冷 10 min后于室温6 0 min内测定吸光度 A6 70 nm值。根据 D-核糖测定标准曲线之回归方程 y=0 .0 0 7x,即可求得发酵液 D-核糖浓度(m g/ ml) X=0 .0 476× A× n.。实验表明 ,发酵培养基成分 (葡萄糖、玉米浆、硫酸铵、碳酸钙 ) ,经 10 0 0倍稀释后对 D-核糖测定结果干扰较小。

S-921菌株及其发酵液对苹果树腐烂病菌作用的试验研究

采用平板和离体培养法测定S-921菌株及其发酵液对苹果树腐烂病菌的作用。结果表明,S-921菌对苹果树腐烂病菌有较强的抗生作用,二者在PDA平极培养基上共同培养时,能产生直径30～40mm的抑菌圈。将苹果树腐烂病菌用S-921菌株发酵液浸泡处理12小时,可失去致病能力。离体培养的结果表明,刮除病斑后涂抹S-921菌株发酵液的治疗效果最好,治愈率达100％;在病斑处划刻(间隔2～3mm)后涂抹的,仅能短时期的抑制病斑扩大,不能治愈。S-921菌发酵液对苹果树腐烂病菌具有溶菌作用,使原生质凝集,液泡消失,菌丝壁溶解,原生质外流,菌丝体崩溃而解体。

日本开发乙醇膜法提浓新技术

为了从发醇液中生产接近100%纯熟的乙醇，常规工艺采用二步蒸馏法操作，该操作占总能量需求近55%，因此，改进浓缩步骤是降低生产物乙醇成本的关键。

超滤膜分离技术在植酸酶浓缩中的应用

目的 利用超滤法在低温下操作 ,生物活性物质不易失活的特点 ,探讨超滤法代替薄膜蒸发法浓缩植酸酶发酵液的技术可行性 ,以降低能耗。 方法 采用截留分子量为 2 0 0 0 0的 PU - 2 0 K - PS管式超滤膜系统浓缩 1～ 5批次的植酸酶发酵液 ,测定浓缩倍数、浓缩收率和截留率并观察超滤过程的膜通量及其变化。 结果 植酸酶的浓缩倍数为 6 .5 3倍 ,浓缩收率为 99.6 9% ,截留率为 99.93% ,系统可以在植酸酶的工艺条件下连续浓缩 >10 h,且经过简单清洗后 ,膜通量基本恢复。 结论 用 PU - 2 0 K - PS管式超滤膜系统浓缩植酸酶发酵液在技术上可行。

Effects of Alcohol and Liquid Paraffin on Development of Early Mouse Embryos in vitro

In culturing early mouse embryos in vitro,liquid paraffin and alcohol exert deleterious influence on the development of embryos. Some of light liquid paraffin produced by Chinese factories have proved harmful for early mouse embryos. As shown by our experiments, the nitronaphthalene contained and the specific gravity of liquid paraffin were not involved in the injurious effects.However,alcohol mingled in medium had harmful effects on the development of embryos. At the 0.1% concentration of alcohol in medium the proportion of embryos developing to blastocysts decreased to 73.9%. When the concentration of alcohol was increased to 0.8%, all embryos ceased developing. In our experiments, CO_2 which contained 0.13% alcohol had no visible effects on the development of embrvos in vitro.

Salting-out Extraction of 2,3-Butanediol from Jerusalem artichoke-based Fermentation Broth

The removal of solid impurities and separation of target products from a fermentation broth is becoming more tedious with the utilization of lignocelluloses as source of substrate.2,3-Butanediol,an important chemical used widely is also a main product of sugar-based fermentation carried out by Klebsiella pneumoniae.In this study,we investigated the use of salting-out extraction(SOE) that employed a K2HPO4/ethanol system consisting of 21% ethanol and 17% K2HPO4(mass fraction) to separate 2,3-butanediol from the viscous Jerusalem artichoke-based fermentation broth.After SOE,about 98% of solid matters was removed,and the viscosity decreased from 72.5 mPa s in the original fermentation broth to 4.4 mPa s in the top phase.The partition coefficient and yield of 2,3-butanediol reached 13.4 and 99%,respectively,and 89% of soluble proteins was removed from the broth.The results showed that SOE is an efficient way for isolating 2,3-BD from a highly viscous fermentation broth by removing much of the solid matters within the broth.

Effective and simple recovery of 1,3-propanediol from a fermented medium by liquid–liquid extraction system with ethanol and K_3PO_4

1,3-Propanediol,traditionally obtained from fossils,has numerous industrial applications,including use in the production of high performance polymers.The microbial production of 1,3-propanediol presents several opportunities,and the final purity grade determines its price and commercial viability.The development of novel separation technology could improve the economic viability of the bioproduction of 1,3-propanediol.Thus,we investigated salting-out extraction as a novel process for 1,3-propanediol recovery from fermentation broth.Initially,a screening for the best salt/solvent combination was conducted and then optimized using the response surface methodology.The solvents studied were methanol,ethanol,isopropanol and acetone,and the salts examined were K_2HPO_4,Na_2CO_3,K_2CO_3,(NH_4)_2SO_4,NaHPO_4,K_3PO_4 and C_6H_5NaO_7.The optimal extraction system consisted of 34 wt%K_3PO_4,28 wt% ethanol,and 38 wt% fermentation broth containing 23.0 g·L^(-1)1,3-propanediol,which gave the highest partition coefficient of 33 and recovery yield of 97%.The results demonstrated that salting-out extraction was a promising method for 1,3-propanediol recovery from fermentation broth.

Optimization of dilute acid hydrolysis of Enteromorpha

Acid hydrolysis is a simple and direct way to hydrolyze polysaccharides in biomass into fermentable sugars. To produce fermentable sugars effectively and economically for fuel ethanol, we have investigated the hydrolysis of Enteromorpha using acids that are typically used to hydrolyze biomass： H2SO4, HC1, H3PO4 and C4H404 （maleic acid）. 5%（w/w） Enteromorpha biomass was treated for different times （30, 60, and 90 min） and with different acid concentrations （0.6, 1.0, 1.4, 1.8, and 2.2%, w/w） at 121~C. H2SO4 was the most effective acid in this experiment. We then analyzed the hydrolysis process in H2SO4 in detail using high performance liquid chromatography. At a sulfuric acid concentration of 1.8% and treatment time of 60 min, the yield of ethanol fermentable sugars （glucose and xylose） was high, （230.5 mg/g dry biomass, comprising 175.2 mg/g glucose and 55.3 mg/g xylose）, with 48.6% of total reducing sugars being ethanol fermentable. Therefore, Enteromorpha could be a good candidate for production of fuel ethanol. In future work, the effects of temperature and biomass concentration on hydrolysis, and also the fermentation of the hydrolysates to ethanol fuel should be focused on.