应用煎炸废油发酵制备槐糖脂生物表面活性剂

应用正交实验,优化了假丝酵母菌O-13-1以煎炸废油为油溶性碳源发酵制备槐糖脂的条件,并应用高效液相色谱-高分辨串联质谱(HPLC-MS/MS)鉴定了所产槐糖脂同系物的组成及结构。结果表明,经正交实验优化的O-13-1菌株以煎炸废油为底物制备槐糖脂的摇瓶发酵条件为:摇床转速200 r/min,双碳源质量浓度均为90 g/L,温度为25℃,接种量为体积分数12%。在此条件下,槐糖脂产量达到最大,为73.26 g/L;O-13-1菌株以煎炸废油为底物所合成槐糖脂由9种乙酰基取代的内酯型和酸型槐糖脂同系物构成,内酯型槐糖脂同系物所占质量分数达76%。基于摇瓶得到的以煎炸废油为油溶性碳源的优化发酵条件,O-13-1菌株在5 L自动发酵罐中转速500 r/min时发酵合成槐糖脂产量可达163.28 g/L。以煎炸废油为碳源发酵槐糖脂的原料成本较普通大豆油降低18%,在有效降低槐糖脂生产成本的同时,实现了煎炸废油的资源化利用。     

应用煎炸废油发酵制备槐糖脂生物表面活性剂

应用正交实验,优化了假丝酵母菌O-13-1以煎炸废油为油溶性碳源发酵槐糖脂的条件,并应用高效液相色谱-高分辨串联质谱（HPLC-MS/MS）鉴定了所产槐糖脂同系物的组成及结构。结果表明,经正交实验优化的O-13-1菌株以煎炸废油为底物制备槐糖脂的摇瓶发酵条件为：摇床转速200r/min,双碳源添加量均为90g/L,温度为25℃,接种量为体积分数12%,槐糖脂产量在菌株稳定生长期的后期即204h时达到最大,为57.64g/L;O-13-1菌株以煎炸废油为底物所合成槐糖脂由9种乙酰基取代的内酯型和酸型槐糖脂同系物构成,内酯型槐糖脂同系物所占质量分数达76%。基于摇瓶得到的以煎炸废油为油溶性碳源的优化发酵条件,O-13-1菌株在5L自动发酵罐中转速500r/min时发酵合成槐糖脂产量可达163.28g/L。以煎炸废油为碳源发酵槐糖脂的原料成本较普通大豆油降低18%,在有效降低槐糖脂生产成本的同时,实现了煎炸废油的资源化利用。     

餐厨废油资源化产鼠李糖脂的研究进展

综述了餐厨废油的危害及处理现状、鼠李糖脂的应用价值及生产菌株、餐厨废油资源化产鼠李糖脂的研究现状,指出了现有工艺存在的问题,提出了提高鼠李糖脂产量的优化途径,并展望了其未来发展方向和应用前景。     

微生物合成鼠李糖脂生物表面活性剂的研究进展

微生物合成的鼠李糖脂是一类重要的生物表面活性剂,具有易被生物降解、表面活性良好等优点,应用前景广阔。目前用于发酵合成鼠李糖脂的菌株主要为假单胞菌属。综述了产鼠李糖脂菌株的发现与筛选、鼠李糖脂的生物合成途径与代谢调控关系、鼠李糖脂发酵过程的优化与控制、高产鼠李糖脂工程菌株的构建等方面的研究进展,并对其研究趋势进行了展望。     

餐厨废弃油脂生物合成鼠李糖脂研究进展

综述了餐厨废弃油脂生物合成鼠李糖脂的研究进展,此外,还总结了餐厨废弃油脂生物合成鼠李糖脂的增产策略,如碳源、氮源、微量元素、pH及培养方式等因素对其产量的限制及其影响,并对利用餐厨废弃油脂生产鼠李糖脂步入正轨化大规模生产的重点研究领域进行了展望。     

鼠李糖脂的发酵及其在清洗原油储罐中的应用

从被油类污染的土壤中得到一株分泌鼠李糖脂的铜绿假单胞菌P aeruginosa ZJU u1,利用烹饪废油为碳源,在摇瓶上对此菌株进行发酵培养,鼠李糖脂的产量在120 h后达到12.54g/L.获得的发酵液可以使溶液表面张力降低到37×10-3N/m,临界胶束浓度(CMC)为63.3 mg/L.实验结果表明,发酵液可提高罐底油泥的洗脱效果,提高储油罐罐底油泥中原油的回收率.     

鼠李糖脂的发酵及其在清洗原油储罐中的应用

从被油类污染的土壤中得到一株分泌鼠李糖脂的铜绿假单胞菌P aeruginosa ZJU u1,利用烹饪废油为碳源,在摇瓶上对此菌株进行发酵培养,鼠李糖脂的产量在120 h后达到12.54 g/L.获得的发酵液可以使溶液表面张力降低到37×10-3 N/m,临界胶束浓度(CMC)为63.3 mg/L.实验结果表明,发酵液可提高罐底油泥的洗脱效果,提高储油罐罐底油泥中原油的回收率.     

生物表面活性剂鼠李糖脂研究概况

从化学结构、理化性质、生产方法、提取和纯化、主要应用、研究现状等方面综述了鼠李糖脂的研究,指出了鼠李糖脂未来的研究重点,一是通过诱变和基因工程,筛选出产量更高、遗传性更稳定的高产菌株;二是优化发酵工艺,开发出适合规模化生产的发酵工艺;三是拓宽廉价原材料的范围,进一步降低鼠李糖脂的生产成本;四是对鼠李糖脂的结构、理化性质及其构效关系进行更深入的研究,为鼠李糖脂的开发应用创造更广阔的前景。     

鼠李糖脂促进含油餐饮废水的生物降解

研究生物表面活性剂鼠李糖脂发酵液在含废油餐饮废水的好氧处理过程中的降解性能.结果表明,作为一种高效、绿色环保的生物表面活性剂,鼠李糖脂发酵液能非常迅速地促进废水中餐饮废油的生物降解.在采用活性污泥法处理实际废水的曝气池中的试验进一步表明,对油脂的生物降解能力而言,添加鼠李糖脂发酵液比未添加的处理效果要显著得多;同时,温度和糖脂发酵液的添加量对降解能力有较明显的影响.在27℃和糖脂加量为1倍CMC的最优条件下,废水中废油24 h的生物降解率高达89%.     

鼠李糖脂对餐厨垃圾厌氧发酵过程中水解酶活性的影响

水解酶的活性直接影响有机物厌氧分解的效率,为了研究生物表面活性剂对有机废弃物厌氧发酵过程的影响,以餐厨垃圾为发酵原料,添加生物表面活性剂鼠李糖脂,添加量分别为发酵物总量的0,0.01%,0.02%,0.03%,0.04%和0.05%,35℃下发酵25 d,测定发酵过程中淀粉酶、脂肪酶、蛋白酶和纤维素酶的活性变化情况。结果表明,鼠李糖脂添加量为0.01%~0.03%时,餐厨垃圾发酵累积产气量随添加量的增加有较大幅度提高,添加量超过0.03%后,产气量与对照相比增加到40%以上,但增加幅度放缓甚至略有降低。鼠李糖脂添加量达到0.03%以上时,COD去除率接近70%,TS(总固体含量)降解率增加到30%以上,VS(挥发性固体含量)降解率增加到50%左右。鼠李糖脂添加量在0.01%~0.03%范围内时,4种水解酶的活性与添加量的增加成正比,添加量达到0.03%时,纤维素酶、蛋白酶、脂肪酶和淀粉酶的活性峰值分别比对照提高60.23%,30.47%,38.51%和36.16%,此后酶活增幅不明显。综上结果表明,添加鼠李糖脂可以提高餐厨垃圾厌氧发酵过程中的水解酶活性,适宜的添加量应为0.03%左右。     

餐厨垃圾酸性发酵及其产物的脱氮特性研究

利用餐厨垃圾为基质进行酸性发酵并利用其发酵产物作为反硝化碳源,结果发现餐厨垃圾酸性发酵过程中具有明显的阶段性。利用不同阶段的发酵液作为反硝化碳源,得出以乳酸为主的发酵液与乙酸钠相似,具有良好的反硝化能力和较快的反硝化速率的结论。而以VFAs为主的发酵液能够彻底实现反硝化,但容易导致NO2--N积累。     

Solid-state production of esterase using fish processing wastes by Bacillus altitudinis AP-MSU

The bacterium Bacillus altitudinis AP-MSU, able to produce esterase was isolated from the gut of marine fish Sardinella longiceps. The esterase production was investigated in solid-state fermentation experiment using various fish processing waste meal. Among the tested fish processing wastes, red grouper waste emerged as the best source for higher esterase production. The suitable surfactant and triglyceride identified to increase the lipase production was neem oil. Effect of individual carbon and nitrogen sources supplementation on esterase production revealed that fructose and peptone aided the higher esterase production than the other tested carbon and nitrogen sources. The suitable concentration of sodium chloride for higher esterase production was at 5%. Effect of surfactants and trace elements on esterase production showed that Tween 20 and zinc sulphate, respectively produced maximum amount of esterase. The effect of physical parameters on lipase production revealed that 50 °C temperature and pH 7–8 were optimum for higher esterase production. Statistical optimization with Plackett–Burman design showed that neem oil, NaCl and fructose were found to be the most predictive factors for esterase production by this strain.     

Chiral resolution of differently substituted racemic acetyl‐1‐phenyl ethanol using lipase from Bacillus subtilis

In the present investigation a Lipase producing strain, Bacillus subtilis (MTCC‐121) was grown on various media containing different sources of carbon, nitrogen and other nutrients. The best media found for the production of lipase was M2 media containing 0.4% peptone, 0.2% beef extract and 1% NaCl. Lipase produced from this culture was used for the kinetic resolution of racemic acetyl‐1‐phenyl ethanol and its derivatives, which are important as chiral auxiliaries and intermediates in the synthesis of natural products, pharmaceuticals and agrochemicals. The lipase resolved these substrates after 48 h with enantiomeric excess of 90–98% and conversion 40–48%. Copyright © 2010 Society of Chemical Industry     

城市生活垃圾焚烧炉各工艺参数对二噁英生成的影响

二英的致命毒性及其对人体可能产生的影响已经引起了广大研究者的关注。城市生活垃圾的焚烧是二英形成的主要途径之一 ,因此如何控制垃圾焚烧中二英的形成和排放是目前研究的热点问题之一。介绍了二英的性质以及各工艺参数 (燃烧温度、形成二英的母体物质、碳源和氯源、表面材料、反应时间、金属离子催化剂以及气体组成和水分等 )对二英生成的影响     

The nitrogen fertiliser value and other agronomic benefits of industrial biowastes

An estimated 7 million t of industrial biowastes are landspread annually in the UK. Quantitative research into their fertiliser replacement value and agronomic benefit is required to increase their use in agriculture, recycle valuable nutrients, and contribute to the reduction of biodegradable waste sent to landfill. A programme of systematically designed field experiments was established to quantify the agronomic value of a range of industrial biowastes, including examples from the vegetable, meat and dairy processing industries and digested biowastes from industrial aerobic and anaerobic digestion plants. Dewatered anaerobically digested biosolids (DMAD) was included as a reference material. Yield and N offtake responses of perennial ryegrass, at five rates of application of each biowaste type were used to calculate the N equivalency relative to mineral N fertiliser. Liquid thermophilic aerobic digestate (LTAD) of food waste was an effective source of available N, with an N equivalency of 59–76 %. Liquid mesophilic anaerobic co-digestates of livestock slurry and food waste (LcoMAD) had N equivalencies between 68 and 85 %. Vegetable processing waste and brewing waste (yeast) had N equivalency values of 45 and 89 %, respectively. Regarding other nutrient elements, the biowastes were generally a source of P, vegetable wastes were significant sources of K, and DMAD and the dewatered anaerobically digested organic fraction of municipal solid waste (DMADMSW) were effective sources of S. Certain waste types were not effective sources of N for crop growth (e.g. potato processing wastes, kieselguhr) and require further investigation at greater rates of application to determine their agronomic benefit.     

Achieving the Best Yield in Glycolipid Biosurfactant Preparation by Selecting the Proper Carbon/Nitrogen Ratio

Pseudomonas aeruginosa RS29, the native biosurfactant-producing strain isolated from the oil fields of Assam, India was used to investigate the influence of the carbon nitrogen ratio on production of the biosurfactant. The biosurfactant producing ability of the strain was measured based on surface tension (ST) reduction of the culture medium and the emulsification (E24) index. Production was greatly influenced by the sources of nitrogen and carbon as well as the carbon to nitrogen (C/N) ratio. Sodium nitrate was the best nitrogen source and the water miscible carbon source, glycerol was observed as the best carbon source for maximum biosurfactant production. The C/N ratio 12.5 allowed the maximum production of biosurfactant by the RS29 strain. At this C/N ratio, 55 % ST of the culture medium was reduced by the produced biosurfactant. Concentrations of crude and rhamnolipid biosurfactant obtained at this particular C/N ratio were 5.6 and 0.8 g/l respectively. The RS29 strain was novel as it was able to produce a sufficient amount of biosurfactant utilizing a much lower amount of the water miscible carbon source, glycerol. Extraction of the biosurfactant by a chloroform–methanol (2:1) mixture was the best method to obtain the highest biosurfactant from the culture medium of the strain. The biosurfactant was confirmed as a mixture of mono and di-rhamnolipid congeners, Rha–C₁₀–C₁₀–CH₃ being the most abundant one. The biosurfactant was a good foaming and emulsifying agent.     

农村生物质能利用发展模式分析

本文归纳并提出了我国农村生物质能利用的3种主要发展模式,包括户用循环利用型、分布式能源型和商品化燃料产品型,并分析了这些发展模式的主要特点和发展瓶颈。同时就如何发展我国农村生物质能源,推进产业化的发展思路提出了建议:1)基于不与粮食争地和发展循环型农业考虑,优先发展利用农业废弃物原料的生物质能转化技术;2)启动能源农业采取先易后难的发展战略,优先应用现有的现代农业技术和传统高产的农产品原料;3)选择发展模式要根据当地气候、农作方式和经济发展水平,因地制宜,强调多能互补;4)重视生物质能源技术多学科交叉的特点、尤其要注重高新技术应用, 加强技术引进。     

Polyhydroxyalkanoates: Recent Advances in Their Synthesis and Applications

Polyhydroxyalkanoates (PHAs) are microbial biopolymers (polyesters) that have a wide range of functions and applications. They serve in nature mainly as carbon and energy storage materials for a variety of microorganisms. In past decades, their utilization has attracted much attention, from commodities and degradable plastics to specialty performance materials in medicine. PHA biosynthesis has been well understood, and it is now possible to design bacterial strands to produce PHAs with desired properties. The substrates for the fermentative production of PHAs are very manifold: some are derived from food‐based carbon sources (e.g., fats and oils (triglycerids)), thus raising concerns with regard to the sustainability of their productions in terms of crop area and food. In addition, hemicellulose hydrolysates, crude glycerol, and methanol are very promising carbon sources for the sustainable production of PHAs. The integration of PHA production within a modern biorefinery is an important issue and can result in a simultaneous production of biofuels and bioplastics. Furthermore, many chemical‐synthetic procedures by means of efficient catalysts can give access to a variety of PHAs. This article summarizes recent developments in these fields and emphasizes the importance of a sustainable PHA‐based industry. Practical Applications: Practical applications of the microbial polyesters PHAs are, for example, a variety of sustainably produced commodities as well as special applications in (bio)medicine, for example, tissue engineering.     

Food processing wastewater purification by microalgae cultivation associated with high value-added compounds production — A review

Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production. However, the high energy cost associated with complicated biorefinery (e.g. microalgae cultivation, harvesting, drying, extraction, conversion, and purification) is a critical challenge that inhibits its large-scale application. Among different nutrition (e.g. carbon, nitrogen and phosphorous) sources, food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity. In this review, the characteristic of different food wastewater is summarized and compared. The potential routes of value-added products (i.e. biofuel, pigment, polysaccharide, and amino acid) production along with wastewater purification are introduced. The existing challenges (e.g. biorefinery cost, efficiency and mechanism) of microalgal-based wastewater treatment are also discussed. The prospective of microalgae-based food processing wastewater treatment strategies (such as microalgae-bacteria consortium, poly-generation of bioenergy and value-added products) is forecasted. It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce, conversion and reutilization.     

中国沉淀白炭黑工业中废气、废液资源化利用现状与研究

详细叙述了中国沉淀法白炭黑生产过程中废气、废液产生的来源及危害,指出直接向环境排放二氧化碳废气、硫酸钠废液不仅浪费资源、污染环境,而且严重限制其行业可持续发展。阐述了两种污染物资源化利用的各种方法,其中二氧化碳可以转化成沉淀碳酸钡、轻质碳酸钙等,硫酸钠可以转化成硫酸钡、硫酸钾、硫化钠等工业产品。通过分析、对比资源化利用的各种方法,建议白炭黑生产企业要积极与钡盐行业进行合作联营生产,这样不仅减少“三废”排放,保护环境,而且是污染物资源化利用最佳途径,并且具有一定的可行性。