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Due to their non-toxic nature, biodegradability and production from renewable resources, research has shown an increasing interest in the use of biosurfactants in a wide variety of applications. This paper reviews the characterization of rhamnolipid and sophorolipid biosurfactants based on their hydrophilicity/hydrophobicity and their ability to form microemulsions with a range of oils without additives. The use of the biosurfactants in applications such as detergency and vegetable oil extraction for biodiesel application is also discussed. Rhamnolipid was found to be a hydrophilic surfactant while sophorolipid was found to be very hydrophobic. Therefore, rhamnolipid and sophorolipid biosurfactants in mixtures showed robust performance in these applications. 相似文献
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Sung-Chyr Lin 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,66(2):109-120
Surfactants find applications in a wide variety of industrial processes. Biomolecules that are amphiphilic and partition preferentially at interfaces are classified as biosurfactants. In terms of surface activity, heat and pH stability, many biosurfactants are comparable to synthetic surfactants. Therefore, as the environmental compatibility is becoming an increasingly important factor in selecting industrial chemicals, the commercialization of biosurfactant is gaining much attention. In this paper, the general properties and functions of biosurfactants are introduced. Strategies for development of biosurfactant assay, enhanced biosurfactant production, large scale fermentation, and product recovery are discussed. Also discussed are recent advances in the genetic engineering of biosurfactant production. The potential applications of biosurfactants in industrial processes and bioremediation are presented. Finally, comments on the application of enzymes for the production of surfactants are also made. 相似文献
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《分离科学与技术》2012,47(14):2249-2254
Rhamnolipid and saponin were used as biosurfactant to form cellulase-biosurfactant complex systems. Acetone, ethanol, and methanol were tested recovery solvents, and among the three tested recovery solvents, acetone was the optimum one. Using acetone as recovery solvent and with the addition of 0.1 mM NaCl, the highest protein and activity recovery were yielded. The optimum conditions during the process for cellulase-rhamnolipid complex systems and cellulase-saponin complex systems were discovered. Two cellulase-biosurfactant complex systems were better than the cellulase-AOT complex system. Experimental results showed that biosurfactants have great potential in protein precipitation. 相似文献
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Glayol Modabber Abbas Akhavan Sepahi Fatemeh Yazdian Hamid Rashedi 《Journal of surfactants and detergents》2023,26(1):3-11
Surfactin is one of the most important lipopeptide biosurfactants obtained by biocatalysts of Bacillus subtilis. The aim of this study was to isolate surfactin-producing bacilli from native soils of the country (Iran), investigate their properties, convert surfactin to surfactin micelles, determine the properties of surfactin micelles and investigate the effect of starch-coated Fe0 and Fe3+ nanoparticles on the production of surfactin from B. subtilis. To do so, 20 bacilli were isolated from the native soil sample by heat shock method and genome sequenced by SrRNA16 method. The samples with strong β-hemolysis activity were screened as surfactant-producing strains. Two species of 61 and 63 (B. subtilis subspecies. Inaquosorum) were selected and examined by quantitative and qualitative screening tests such as hemolysis activity, surfactin production, droplet aggregation, emulsifying activity, and surface tension reduction in MSM medium containing Fe0 and Fe3+ nanoparticles. Surfactin was converted to surfactin micelles by sonication and confirmed by SEM. The antimicrobial and emulsifying activity and surface tension reduction of surfactin micelles were investigated. According to the results, the surface tension reduction of surfactin micelles was greater than that of surfactin. The strain 61 (99.7%) culture in 5 L bioreactors containing Fe3+ nanoparticles produced more surfactin than culture of the same strain without nanoparticles. This study presents an efficient method to increase the biosynthesis of microbial metabolites. 相似文献
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假单胞菌O-2-2产鼠李糖脂的结构表征及理化性质 总被引:8,自引:0,他引:8
利用液相色谱/质谱联用仪分析了铜绿假单胞菌O-2-2以正十八烷为碳源所产鼠李糖脂生物表面活性剂的组成。共检出21种鼠李糖脂的同系物,都由1~2分子的鼠李糖和1~2个含β-羟基的碳链长度为8~12的饱和或不饱和脂肪酸构成;主要组分为α-L-吡喃鼠李糖苷-β-羟基癸酰-β-羟基癸酸和2-O-α-L-吡喃鼠李糖苷-α-L-吡喃鼠李糖苷-β-羟基癸酰-β-羟基癸酸。该糖脂类生物表面活性剂可将水的表面张力降至28·6mN/m,临界胶束浓度为1·3×10-4mol/L,在120℃加热4h或者在ρ(NaCl)=100g/L或ρ(CaCl2)=20g/L的盐溶液中仍能保持表面活性。 相似文献
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该文综述了超滤技术的原理、分离过程、发酵液的性质以及超滤膜和超滤条件对生物酶超滤性能的影响。并从发酵液的处理、超滤膜和超滤过程的优化三方面出发,对近期提高超滤性能取得的成果进行了总结和讨论。最后指出生物酶超滤技术的未来发展方向有以下几点:超滤数学模型的开发;提高酶的稳定性;超滤膜的改进和开发;超滤工艺的改进。 相似文献
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假单胞菌AB93066产鼠李糖脂发酵条件的优化 总被引:4,自引:0,他引:4
通过单因素实验和正交实验对铜绿假单胞杆菌AB93066产鼠李糖脂(RL)的摇瓶发酵培养基配方和产生规律进行了研究。结果表明,最佳培养基配方为:ρ(酵母膏)=0.2 g/L,ρ(豆油)=120 g/L,ρ(NaNO3)=6.5 g/L,ρ(KH2PO4)=1.0 g/L,ρ(Na2HPO4.12H2O)=1.0 g/L,ρ(MgSO4.7H2O)=0.1 g/L,ρ(FeSO4.7H2O)=0.2 g/L,pH=6.0。RL的收获期在发酵后156~168 h最佳。发酵生产RL的扩大实验表明,在最优发酵条件下RL的产量可达56 g/L以上,提取后的RL可将去离子水的表面张力降至29.01 mN/m。用高效液相色谱/质谱联用仪进一步分析了所提取的RL的组成,它分别为二鼠李糖脂(R1)和单鼠李糖脂(R2)两种同系物。R1和R2的表观临界胶束浓度(CMC)分别为0.03 mmol/L和0.04 mmol/L。 相似文献
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Jin-Feng Liu Serge Maurice Mbadinga Shi-Zhong Yang Ji-Dong Gu Bo-Zhong Mu 《International journal of molecular sciences》2015,16(3):4814-4837
Lipopeptides produced by microorganisms are one of the five major classes of biosurfactants known and they have received much attention from scientific and industrial communities due to their powerful interfacial and biological activities as well as environmentally friendly characteristics. Microbially produced lipopeptides are a series of chemical structural analogues of different families and, among them, 26 families covering about 90 lipopeptide compounds have been reported in the last two decades. This paper reviews the chemical structural characteristics and molecular behaviors of surfactin, one of the representative lipopeptides of the 26 families. In particular, two novel surfactin molecules isolated from cell-free cultures of Bacillus subtilis HSO121 are presented. Surfactins exhibit strong self-assembly ability to form sphere-like micelles and larger aggregates at very low concentrations. The amphipathic and surface properties of surfactins are related to the existence of the minor polar and major hydrophobic domains in the three 3-D conformations. In addition, the application potential of surfactin in bioremediation of oil spills and oil contaminants, and microbial enhanced oil recovery are discussed. 相似文献
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本研究的目的是开发一种新型的泡沫浮选耦合超滤技术的方法,以实现从有机废液体系中经济、高效地回收纳米TiO2光催化剂。首先,对超滤膜分离有机废液中纳米TiO2光催化剂的使用效率,包括透过通量和截留率进行评价。随后,为了减少超滤操作进料液中纳米TiO2光催化剂的浓度,在泡沫浮选阶段确定以阳离子表面活性剂——十六烷基三甲基溴化铵(CTAB)作为捕获剂,研究了CTAB浓度、气体体积流速、分布器孔径对泡沫浮选回收纳米TiO2光催化剂富集效率的影响。最后,确定泡沫浮选耦合超滤耦合回收纳米TiO2光催化剂的工艺条件。试验结果表明,采用耦合工艺,在pH 7.0、CTAB浓度0.20g/L、气体体积流速15mL/min以及分布器孔径180μm的条件下,纳米TiO2光催化剂富集比和回收率分别为22.52和99%,同时膜的使用寿命较非耦合操作提高了133%。 相似文献
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Maity JP Lin TJ Cheng HP Chen CY Reddy AS Atla SB Chang YF Chen HR Chen CC 《International journal of molecular sciences》2011,12(6):3821-3830
In this study the "green chemistry" use of the biosurfactant surfactin for the synthesis of calcium phosphate using the reverse microemulsion technique was demonstrated. Calcium phosphates are bioactive materials that are a major constituent of human teeth and bone tissue. A reverse microemulsion technique with surfactin was used to produce nanocrystalline brushite particles. Structural diversity (analyzed by SEM and TEM) resulted from different water to surfactin ratios (W/S; 250, 500, 1000 and 40,000). The particle sizes were found to be in the 16-200 nm range. Morphological variety was observed in the as-synthesized microemulsions, which consisted of nanospheres (~16 nm in diameter) and needle-like (8-14 nm in diameter and 80-100 nm in length) noncalcinated particles. However, the calcinated products included nanospheres (50-200 nm in diameter), oval (~300 nm in diameter) and nanorod (200-400 nm in length) particles. FTIR and XRD analysis confirmed the formation of brushite nanoparticles in the as-synthesized products, while calcium pyrophosphate was produced after calcination. These results indicate that the reverse microemulsion technique using surfactin is a green process suitable for the synthesis of nanoparticles. 相似文献
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综述了生物表面活性剂在日化行业的研究进展和用于日化行业的生物表面活性剂新产品,探讨了生物表面活性剂在日化行业的应用优势及限制因素,指出了应对措施并对其在日化行业的应用前景进行了展望。 相似文献
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N. Mameri D. Abdessemed D. Belhocine H. Lounici C. Gavach J. Sandeaux R. Sandeaux 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,67(2):169-175
The recovery and concentration of proteins from the waste water of a fish plant was achieved by ultrafiltration. Two UF modules equipped with Ceraver and Patterson Candy International (PCI) membranes were tested. Despite different cut-off values, similar apparent rejection coefficients (70% and 80% respectively) were obtained. Optimum economic conditions were established, corresponding to average transmembrane pressures of 2·2 × 105 and 3·8 × 105 Pa and tangential flow rates of 6·0 and 0·47 m s−1 for Ceraver and PCI membranes, respectively. The protein concentration in the feed solution was increased from 5 to 35 g dm−3. The study showed that the method could reduce pollution due to organic matter by decreasing the value of the Biological Oxygen Demand after 5 days (BOD5) by about 80%. 相似文献
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通过正交实验对铜绿假单胞杆菌产鼠李糖脂(RL)的发酵条件进行了优化,并采用预处理酸沉淀冷冻干燥法新工艺提取RL。在最优发酵条件下RL的产量可达56 g/L以上。提取后的RL由二鼠李糖脂和单鼠李糖脂两种同系物组成,可将去离子水的表面张力降至29.01 mN/m。该RL提取工艺是一项绿色工艺。 相似文献
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Saurabh C. Singh 《分离科学与技术》2017,52(14):2252-2261
The present work aimed to study the performance of ultrafiltration (UF) membranes for hemicelluloses separation, from a caustic-containing highly alkaline, cellulose purification solvent stream of viscose rayon production process, and to understand the membrane behaviour, effect of multiple use cycle, identify potential performance drawbacks and propose possible solutions. Screening experiments showed that an UF membrane with a nominal molecular weight cut-off value of 3 kDa can be used to separate hemicelluloses from alkaline process stream. UF membrane was found to be prone to performance deterioration with time due to fouling. Higher feed temperature helped in improving the membrane flux values while maintaining hemicelluloses retention. 相似文献