This study aims to optimize biosurfactant production by Streptomyces gobitricini strain BS-2.After the initial screening,the effective factors on the production of biosurfactant were investigated with the two-level fa...This study aims to optimize biosurfactant production by Streptomyces gobitricini strain BS-2.After the initial screening,the effective factors on the production of biosurfactant were investigated with the two-level factorial statistical.The physical and chemical features and structure of the biosurfactant crafted were analyzed using FTIR,CHNS,EDX,and SEM.The extracted biosurfactant resulted in a decrease in interfacial tension from 72 mN/m to 29 mN/m,with a critical micelle concentration(CMC)of 300 mg/mL.The optimum medium for biosurfactant production that led to utmost diminution in culture broth surface tension(29 mN/m)was:crude oil(1.5%,v/v),hydrolyzed protein(1 g/L),yeast extract(0.5 g/L),molasses(1.5 g/L)and olive oil(1%v/v).The glycolipid organization of the microbial surfactant was confirmed via FTIR,CHNS,EDX,and SEM analysis.Analysis using GC indicated that the presence of biosurfactant increased crude oil degradation by S.gobitricini strain BS-2 dramatically(87%)and this bacterium effectively degraded most of its alkane components.Furthermore,the glycolipid biosurfactant displayed significant development repression against therapeutic bacterial microbes.In summary,the glycolipid biosurfactant produced by S.gobitricini strain BS-2 exhibited diverse functional properties and showed promise for potential biomedical and biotechnological applications.展开更多
Crude petroleum pollution causes some serious ecological disasters in the ocean.Marine sediment microbial fuel cells(MSMFCs)have been utilized as a novel method for in-situ degradation and a long-term power source.Her...Crude petroleum pollution causes some serious ecological disasters in the ocean.Marine sediment microbial fuel cells(MSMFCs)have been utilized as a novel method for in-situ degradation and a long-term power source.Herein,the effect of different concentrations of rhamnolipids biosurfactant on the electrochemical performance of MSMFCs anode and the higher efficiency of oil degradation are creatively investigated.The results indicate that the anode in sediment containing rhamnolipids effectively enriches the indigenous electrogenic Pseudophaeobacter and Pseudomonas,which significantly enhances the electrochemical performance of the MSMFCs.Under rhamnolipids at the concentration of 200 mg kg^(-1)in sediment,the anode specific capacitance(401.45 Fm^(-2)),exchange current density(4.87×10^(-2)mAm^(-2)),and cell maximum power density(140.24 mWm^(-2))increase by 2.50,38.65,and 2.11 times,respectively,in comparison with its natural sediment.And the oil degradation rate(40.06%)was higher than the blank(17.55%).It demonstrates that the synergistic effect between electrochemical catalytic degradation and emulsifying solubilization of rhamnolipids surfactant directly accelerates the degradation of petroleum in marine sediment,which will provide a novel method and theoretical guidance for in-situ degradation and efficient removal of crude petroleum on ocean floor.展开更多
Cassava is the most widely distributed food crop in Central Africa. Chikwangue, also known as kwanga in the Republic of Congo, is a starchy fermented cassava product that is a staple food in the country. This work aim...Cassava is the most widely distributed food crop in Central Africa. Chikwangue, also known as kwanga in the Republic of Congo, is a starchy fermented cassava product that is a staple food in the country. This work aims to determine the composition of bioactive compounds in chikwangue, including biosurfactant-like molecules and proteins content. Antibacterial activities were investigated through the preliminary emulsification index of chikwangue and fermented paste. Antibacterial assay, 16S rRNA, cytK, hblD, nheB and entFM PCR amplifications, DNA sequence analysis, NCBI homology analysis, and phylogenic tree were performed using NGPhylogeny. fr and iTOL (interactive of live). Fermented cassava paste and chikwangue contain biosurfactants with an emulsification index of 50%. The total protein concentration in fermented cassava paste was 4 g/ml and the chikwangue was 2.5 g/mL Further sequence analysis showed that isolates shared a homology of up to 99.9% with Bacillus cereus PQ432941.1, B. licheniformis PQ432758.1, B. altitudinis PQ432754.1, B. subtilis PQ432759.1, B. mojavensis PQ432755.1, B. tequilensis MT994788.1, B. subtilis MT994789.1, Paenibacillus polymyxa PQ452544.1, B. velezensis PQ452545.1, B. thuringiensis PQ432763.1, B. pumilus PQ432762.1, B. subtilis MT994787.1, B. mycoides PQ432890.1, B. thuringiensis PQ432766.1, B. subtilis PQ432757.1 and B. amyloliquefaciens PQ432756.1. Importantly, the emulsification index (E24) ranged from 60 to 100% and the crude biosurfactant for the Bacillus strains mentioned above could easily inhibit the growth for pathogen Gram-negative bacteria (S. enterica, S. flexneri, E. coli, Klebsiella sp. and P. aeruginosa) with diameters ranging from 2.3 ± 0.1 cm to 5.5 ± 0.4 cm. On the other hand, the diameters of Gram-positive pathogenic bacteria (B. cereus and S. aureus) varied between 1.5 ± 0.5 cm and 4.0 ± 0.2 cm. These findings involve the promise purpose of Bacillus isolated from retted cassava, and this study systematically uncovered the biodiversity and distribution characteristics of retted paste cassava and chikwangue.展开更多
The synergetic effect and underlying mechanism of potassium ferrate(PF)with tea saponin(TS,a biosurfactant)in producing short chain fatty acids(SCFAs)from anaerobic fermentation of waste activated sludge(WAS)were expl...The synergetic effect and underlying mechanism of potassium ferrate(PF)with tea saponin(TS,a biosurfactant)in producing short chain fatty acids(SCFAs)from anaerobic fermentation of waste activated sludge(WAS)were explored in this work.Experimental results showed that 0.2 g PF(g TSS)^(-1)(total suspended solid)combined with 0.02 g TS(g TSS)^(-1) could further improve SCFAs’production,and the maximum SCFAs content reached 2008.7 mg COD L^(-1),which is 1.2 and 4.5 times higher than those with PF and TS individually added,respectively,and 5.3 times higher than that of blank WAS on Day 12.In the model substrates experiments,the degradation rates of bovine serum albumin and dextran with combination of PF and TS were 41.3%±0.1% and 48.5%±0.06%,respectively,on Day 3,which are lower than those in blank WAS(with degradation rates of 72.3%±0.5%and 90.3%±0.3%).It was revealed that the oxidative effect of PF and the solubilization of TS caused more organic matters to be dissolved out from WAS,providing a large number of biodegradable substances for subsequent SCFAs production.While WAS pretreated with the combination of PF and TS,the relative abundances of Firmicutes increased from 6.4%(blank)to 38.6%,and that of Proteobacteria decreased from 41.8%(blank)to 21.8%.The combination of PF and TS promoted the hydrolysis process of WAS by enriching Firmicutes,and then increased acetic acid production by inhibiting Proteobacteria that consumed SCFAs.Meanwhile,at the genus level,acidogenesis bacteria(e.g.,Proteiniclasticum and Petrimonas)were enriched whereas SCFAs consuming bacteria(e.g.,Dokdonella)were inhibited.展开更多
The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological technique...The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections.展开更多
The growth characteristics of petroleum-degrader BS-8（Bacillus sp.） and the factors influencing its biosurfactant production were tested; the biosurfactant releasing mode of BS-8 was speculated by measuring OD600, s...The growth characteristics of petroleum-degrader BS-8（Bacillus sp.） and the factors influencing its biosurfactant production were tested; the biosurfactant releasing mode of BS-8 was speculated by measuring OD600, surface tension and oil displacement of fermentation broth; and the effects of carbon source, nitrogen source, temperature, p H, and Na Cl concentration on biosurfactant production by BS-8 were observed in this study. The results showed that the biosurfactant releasing mode of BS-8 was growth-correlated, the surface tension of BS-8 fermentation broth declined with the total bacteria increasing, and the oil displacement was positive correlated with biosurfactant content in fermentation broth; and the optimal culture conditions for effective biosurfactant production included： glucose as carbon source,yeast extract as nitrogen source, Na Cl concentration of 2%, p H of 7.0 and temperature at 30 ℃.展开更多
Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Res...Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Resonance(NMR)analysis, the purified biosurfactant was considered as a mixture of RL1 and RL2,which are two different types of rhamnolipids.Two different adding methods,adding the purified rhamnolipid and the on-site production of it were compared.The results showed that 0.5 g/L was the optimum co...展开更多
There were six high diesel oil degrading bacteria strains isolated from the oil contaminated soil that collected from Linzi City. The strain YI was able to produce biosurfactant rhanmolipid when cultivated on diesel o...There were six high diesel oil degrading bacteria strains isolated from the oil contaminated soil that collected from Linzi City. The strain YI was able to produce biosurfactant rhanmolipid when cultivated on diesel oil as carbon source. The critical micelle concentrations （CMC） of rhanmolipid in water and in the soil were measured respectively according to the correlation between the surface tension of the medium and the added rhamnolipid concentration. The results showed that the CMC of rhanmolipid in water was 65 mg/L, and was 185 mg/L in soil. The tests on diesel oil biodegradation were conducted with the addition of different concentrations of rhamnolipid in water and in soil respectively. When 0.01% rhanmolipid was added to water, the diesel oil degradation was enhanced. On the contrary, when the same concentration of rhanmolipid was added to the soil, the degradation of diesel oil was inhibited. The results suggested that the rhamnolipid could enhance the diesel oil biodegradation, indicating that the concentration of rhamnolipid was higher than the corresponding CMC in the medium. Kinetics parameters for the diesel oil biodegradation parameters such as biodegradation constant （λ）, coefficient of correlation （r） and half life （t1/2） in both tests were numerically analyzed in this paper, indicating that the moderate concentration of rhamnolipid in the medium could not only enhance the extent of diesel oil biodegradation but also shorten the time for oil remediation.展开更多
Objective:To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3.Methods:Halophilic Bacillus sp.BS3 was isolated from solar salt works,identified by 16S rRNA sequenci...Objective:To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3.Methods:Halophilic Bacillus sp.BS3 was isolated from solar salt works,identified by 16S rRNA sequencing and was used for screening their biosurfactant production.Characters of the biosurfactant and their anticancer activity were analyzed and performed in mammary epithelial carcinoma cell at different concentrations.Results:The biosurfactant were characterized by TLC,FTIR and GC-MS analysis and identified as lipopeptide type.GC-MS analysis revealed that,the biosurfactant had various compounds including 13Docosenamide.(Z);Mannosamine,9- and N,N,N',N'-tetramethyl.Surprisingly the antiviral activity was found against shrimp white spot syndrome virus(WSSV) by suppressing the viral replication and significantly raised shrimp survival(P<0.01).Anticancer activity performed in the mammary epithelial carcinoma cell at different concentrations of biosurfactants,among the various concentrations of biosurfactants such as 0.000 25,0.002 5,0.025,0.25 and 2.5 μ g,the 0.25 μ g concentration suppressed the cells significantly(P<0.05) to 24.8%.Conclusions:Based on the findings,the present study concluded that,there is a possibility to develop eco-friendly antimicrobial and anticancer drugs from the extremophilic origin.展开更多
Bioprosthetic heart valves(BHVs)are important for transcatheter valve replacement.Current commercial BHVs on the market are basically porcine or bovine pericardium(BP)crosslinked with glutaraldehyde(GA).Simply applyin...Bioprosthetic heart valves(BHVs)are important for transcatheter valve replacement.Current commercial BHVs on the market are basically porcine or bovine pericardium(BP)crosslinked with glutaraldehyde(GA).Simply applying GA to BHVs can enhance mechanical stability,but cannot alleviate in vivo calcification.In this work,we developed a two-step decellularization(TSD)strategy to modify this biomacromolecular network,in which BP was post-treated,as the second step of decellularization,with a mild biosurfactant n-dodecyl-β-D-maltoside in a mixture of isopropanol and phosphate-buffered saline after the first step of traditional decellularization and GA cross-linking.The TSD-treated BP exhibited not only low cytotoxicity and excellent mechanical properties in vitro,but also low immune responses and significant anticalcification in vivo.After 60 days of subcutaneous implantation in the back of Wistar rats,the calcium content was,as quantified with an inductively coupled plasma optical emission spectrometer,only 1.1µg/mg compared to 138.6µg/mg in the control group without the post-treatment.In addition,collagen fibrils were observed with field emitting scanning electron microscopy(SEM),and the morphology and composition of the calcified sites resulting from in vivo biomineralization were studied with SEM with energy dispersive spectroscopy and also X-ray diffraction.This study proposes a facile yet effective anticalcification strategy for the modification of the bovine pericardial bioprosthetic heart valve,a natural biomacromolecular network.展开更多
The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°...The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.展开更多
A Bacillus subtilis strain JA-1 isolated from an oil reservoir was studied. This strain is capable of growth and producing biosurfactant at a temperature of 60 ℃. In nutrient medium it produced biosurfactant which re...A Bacillus subtilis strain JA-1 isolated from an oil reservoir was studied. This strain is capable of growth and producing biosurfactant at a temperature of 60 ℃. In nutrient medium it produced biosurfactant which reduced the surface tension from 68.2 mN/m to 28.3 mN/m, with the critical micelle concentration （CMC） of 48 mg/L. The measured surface tension indicated that the biosurfactant possessed stable surface activity at high temperature and a specific range of pH and salt concentrations. The results of thin layer chromatography （TLC） together with FT-IR showed that the metabolic product of strain JA-1 is a lipopeptide biosurfactant. The ability to growth at high temperature and to produce biosurfactant makes strain JA-1 promising for enhanced oil recovery.展开更多
The objective of this study was to examine the effect of biosurfactant on the sorption of phenanthrene （PHE） onto the original or HzO2-treated black loamy soil （typic isohumisols） and red sandy soil （typic ferral...The objective of this study was to examine the effect of biosurfactant on the sorption of phenanthrene （PHE） onto the original or HzO2-treated black loamy soil （typic isohumisols） and red sandy soil （typic ferralisols）. The sorption isotherms were performed with the original and ＂soft＂ carbon-removed soils in the presence and absence of biosurfactant （200 mg/L）. The sorption and degradation of biosurfactant were investigated. The result showed that organic matter played an important role in PHE sorption onto the black loamy and red sandy soils, and the PHE sorption isotherms on the ＂soft＂ carbon-removed soils exhibited more nonlinearity than those on the original soils. The values of partition coefficient （Kd） on the original black loamy soil with or without 200 mg/L biosurfactant were 181.6 and 494.5 mL/g, respectively. Correspondingly, in the red sandy soil, Kd was 246.4 and 212.8 mL/g in the presence or absence of biosurfactant, respectively. The changes of Kd suggested that biosurfactant inhibited PHE sorption onto the black loamy soil, but facilitated PHE sorption onto the red sandy soil. The nonlinearity of PHE sorption isotherm was decreased in the presence of biosurfactant. Site specific sorption might occur during PHE sorption onto both the original and the ＂soft＂ carbon-removed soils in the presence of biosurfactant. It was noted that biosurfactant could also be sorbed onto soils. The maximal sorption capacity of the red sandy soil for biosurfactant was （76.9 ± 0.007） μg/g, which was 1.31 times that of black loamy soil. Biosurfactant was degraded quickly in the two selected soils, and 92% of biosurfactant were mineralized throughout the incubation experiment for 7 d. It implied that biosurfactant should be added frequently when the remediation of polycyclic aromatic hydrocarbon （PAH）-contaminated soils was conducted through PAH desorption approach facilitated by biosurfactant.展开更多
The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented w...The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration.展开更多
One possible application for the excess of glycerol, which is an exceeding byproduct in biodiesel industry, was used as carbon and energy sources for bioproducts synthesis. This work aims to evaluate biosurfactant pro...One possible application for the excess of glycerol, which is an exceeding byproduct in biodiesel industry, was used as carbon and energy sources for bioproducts synthesis. This work aims to evaluate biosurfactant production from glycerol by Pseudomonas aeruginosa EQ 109 isolated from crude oil-contaminated soil. Factorial design 2^3 was utilized to optimize the amount of biosurfactant produced, by using pH （A）, initial biomass concentration （B）, and initial glycerol concentration （C） as independent factors. The experiments were carried out in flasks containing 100 mL of mineral medium. Biosurfactant production was monitored by increase of the emulsification of aviation kerosene （E24） and surface tension reduction （STr）. The results have shown that, at pH = 7.0, in order to increase E24, variables as B and C are the most influential, leading to a maximum value of E24 = 79%, as well as for an increase of GC （GCmax = 49%）. STR was the variable with the best correlation factor for the proposed linear model （R2=0.96） and its maximum value was 48%. Xfwas not significant to the model, although it was influenced by pH and C, with C = 40g/L （Xfmax = 4.56 g/L）.展开更多
Biosurfactants are biomolecules produced by microorganisms, which possess several advantages over their chemical counterparts. Production can be cost-effective if renewable wastes are utilized as substrates. In this s...Biosurfactants are biomolecules produced by microorganisms, which possess several advantages over their chemical counterparts. Production can be cost-effective if renewable wastes are utilized as substrates. In this study, optimization of biosurfactant production by <i>Pseudomonas aeruginosa</i> strain CGA1 was carried out using response surface methodology. The conventional “One factor at a time” method of optimization was initially adopted to ascertain the impact of different renewable wastes on biosurfactant production. Four independent variables were tested: carbon and nitrogen concentration, medium volume, and inoculum size. Biosurfactant production was based on the emulsification index measurement. Results indicated that the preferred carbon source by the isolate was sugar cane molasses. A 2.31-fold increase in biosurfactant yield and emulsification index of 96.3% ± 0.75% under optimized cultural conditions of 20 g/L of molasses, 5 g/L of sodium nitrate, 1.93 ml inoculum size and 60 ml medium volume in 250 ml conical flask were obtained. The regression coefficient (R<sup>2</sup>) value of 84.15% implied adequate fitness of the model. The surface tension of distilled water was reduced from 72.1 mN/m to 35.0 ± 0.0 mN/m, and critical micelle concentration was attained at 60 mg·L<sup>-1</sup>. FTIR and GC-MS analysis indicated that the biosurfactant was a lipopeptide having characteristic lipid and peptide peak values. This study proves that the sole use of agro-industrial wastes for the production of biosurfactant is very efficient, and ensures the economic feasibility of biosurfactant production.展开更多
Joostella strains are emerging candidates for biosurfactant production. Here such ability was analyzed for Joostella strain A8 in comparison with Alcanivorax strain A53 and Pseudomonas strain A6, all previously isolat...Joostella strains are emerging candidates for biosurfactant production. Here such ability was analyzed for Joostella strain A8 in comparison with Alcanivorax strain A53 and Pseudomonas strain A6, all previously isolated from hydrocarbon enrichment cultures made of polychaete homogenates. In pure cultures Joostella sp. A8 showed the highest stable emulsion percentage（78.33%）, hydrophobicity rate（62.67%）, and an optimal surface tension reduction during growth in mineral medium supplemented with diesel oil（reduction of about 12 mN/m）, thus proving to be highly competitive with Alcanivorax and Pseudomonas strains. During growth in pure culture different level of biodegradation were detected for Alcanivorax strain A53（52.7%）,Pseudomonas strain A6（38.2%） and Joostella strain A8（26.8%）. When growing in consortia,isolates achieved similar abundance values, with the best efficiency that was observed for the Joostella-Pseudomonas co-culture. Gas-chromatographic analysis revealed an increase in the biodegradation efficiency in co-cultures（about 90%）, suggesting that the contemporary action of different bacterial species could improve the process. Results were useful to compare the efficiencies of well-known biosurfactant producers（i.e. Pseudomonas and Alcanivorax representatives） with a still unknown biosurfactant producer, i.e. Joostella, and to confirm them as optimal biosurfactant-producing candidates.展开更多
After incubation for 6 -30 h, with the rapid increase of bacterial cell number, surface tension of bacterium BS-8 was reduced sharply from 63.2 mN/m to 39.4 mN/m. The production of biosurfactants by BS-8 was growth-de...After incubation for 6 -30 h, with the rapid increase of bacterial cell number, surface tension of bacterium BS-8 was reduced sharply from 63.2 mN/m to 39.4 mN/m. The production of biosurfactants by BS-8 was growth-dependent. Using glucose as the carbon source, bacterium BS-8 was incubated. Based on centrifugation, precipitation and chromogenie reaction of the culture solution, results indicated that the biosurfactants belonged to lipopeptides. The yield of biosurfaetants isolated and purified from the culture solution was 0.58 g/L, and the critical micelle concentration （CMC） was 90 mg,/L. Under conditions of pH 4 -9, tem- perature 20 -70 ℃, NaCl concentration 1% -6%, biosurfactants predueed by BS-8 exhibited the highest stability.展开更多
This work reports detergents production using biological surfactants, microbiologically synthesized, and compares its foaming power and emulsification capacity to those presented by a petroleum based surfactant. Both ...This work reports detergents production using biological surfactants, microbiologically synthesized, and compares its foaming power and emulsification capacity to those presented by a petroleum based surfactant. Both used microorganisms were capable to produce surfactants, been able to emulsify oil/water mixtures and cause decrease of surface tension of water. The biosurfactant produced from Yarrowia lipolytica has a critical micelle concentration lower than that obtained from Pseudomonas aeruginosa （10 and 30 mg·Lt, respectively）, but the later showed better results in foaming power and emulsification experiments, similar to the synthetic detergent.展开更多
Biosurfactants are biologically active metabolites, and the efficiency of direct screening of new biosurfactants from nature using traditional methods is low, which should be enhanced in the following studies by adopt...Biosurfactants are biologically active metabolites, and the efficiency of direct screening of new biosurfactants from nature using traditional methods is low, which should be enhanced in the following studies by adopting advanced biotechnologies. Rapid development and wide application of microbial culture independent methods, such as metagenomics, metatranscriptomics, metaproteomics and metabonomics, etc., contributes to quickly and precisely screening of novel biological surfactants. We mainly represented the current status of research and applications of biosurfactants in the remediation of petrochemical polluted environment, and also prospected avenues for future research.展开更多
基金Prince Sattam bin Abdulaziz University for funding this research work through the project number(No.PSAU/2023/01/27406).
文摘This study aims to optimize biosurfactant production by Streptomyces gobitricini strain BS-2.After the initial screening,the effective factors on the production of biosurfactant were investigated with the two-level factorial statistical.The physical and chemical features and structure of the biosurfactant crafted were analyzed using FTIR,CHNS,EDX,and SEM.The extracted biosurfactant resulted in a decrease in interfacial tension from 72 mN/m to 29 mN/m,with a critical micelle concentration(CMC)of 300 mg/mL.The optimum medium for biosurfactant production that led to utmost diminution in culture broth surface tension(29 mN/m)was:crude oil(1.5%,v/v),hydrolyzed protein(1 g/L),yeast extract(0.5 g/L),molasses(1.5 g/L)and olive oil(1%v/v).The glycolipid organization of the microbial surfactant was confirmed via FTIR,CHNS,EDX,and SEM analysis.Analysis using GC indicated that the presence of biosurfactant increased crude oil degradation by S.gobitricini strain BS-2 dramatically(87%)and this bacterium effectively degraded most of its alkane components.Furthermore,the glycolipid biosurfactant displayed significant development repression against therapeutic bacterial microbes.In summary,the glycolipid biosurfactant produced by S.gobitricini strain BS-2 exhibited diverse functional properties and showed promise for potential biomedical and biotechnological applications.
基金financially supported by the National Natural Science Foundation of China(No.22075262)。
文摘Crude petroleum pollution causes some serious ecological disasters in the ocean.Marine sediment microbial fuel cells(MSMFCs)have been utilized as a novel method for in-situ degradation and a long-term power source.Herein,the effect of different concentrations of rhamnolipids biosurfactant on the electrochemical performance of MSMFCs anode and the higher efficiency of oil degradation are creatively investigated.The results indicate that the anode in sediment containing rhamnolipids effectively enriches the indigenous electrogenic Pseudophaeobacter and Pseudomonas,which significantly enhances the electrochemical performance of the MSMFCs.Under rhamnolipids at the concentration of 200 mg kg^(-1)in sediment,the anode specific capacitance(401.45 Fm^(-2)),exchange current density(4.87×10^(-2)mAm^(-2)),and cell maximum power density(140.24 mWm^(-2))increase by 2.50,38.65,and 2.11 times,respectively,in comparison with its natural sediment.And the oil degradation rate(40.06%)was higher than the blank(17.55%).It demonstrates that the synergistic effect between electrochemical catalytic degradation and emulsifying solubilization of rhamnolipids surfactant directly accelerates the degradation of petroleum in marine sediment,which will provide a novel method and theoretical guidance for in-situ degradation and efficient removal of crude petroleum on ocean floor.
文摘Cassava is the most widely distributed food crop in Central Africa. Chikwangue, also known as kwanga in the Republic of Congo, is a starchy fermented cassava product that is a staple food in the country. This work aims to determine the composition of bioactive compounds in chikwangue, including biosurfactant-like molecules and proteins content. Antibacterial activities were investigated through the preliminary emulsification index of chikwangue and fermented paste. Antibacterial assay, 16S rRNA, cytK, hblD, nheB and entFM PCR amplifications, DNA sequence analysis, NCBI homology analysis, and phylogenic tree were performed using NGPhylogeny. fr and iTOL (interactive of live). Fermented cassava paste and chikwangue contain biosurfactants with an emulsification index of 50%. The total protein concentration in fermented cassava paste was 4 g/ml and the chikwangue was 2.5 g/mL Further sequence analysis showed that isolates shared a homology of up to 99.9% with Bacillus cereus PQ432941.1, B. licheniformis PQ432758.1, B. altitudinis PQ432754.1, B. subtilis PQ432759.1, B. mojavensis PQ432755.1, B. tequilensis MT994788.1, B. subtilis MT994789.1, Paenibacillus polymyxa PQ452544.1, B. velezensis PQ452545.1, B. thuringiensis PQ432763.1, B. pumilus PQ432762.1, B. subtilis MT994787.1, B. mycoides PQ432890.1, B. thuringiensis PQ432766.1, B. subtilis PQ432757.1 and B. amyloliquefaciens PQ432756.1. Importantly, the emulsification index (E24) ranged from 60 to 100% and the crude biosurfactant for the Bacillus strains mentioned above could easily inhibit the growth for pathogen Gram-negative bacteria (S. enterica, S. flexneri, E. coli, Klebsiella sp. and P. aeruginosa) with diameters ranging from 2.3 ± 0.1 cm to 5.5 ± 0.4 cm. On the other hand, the diameters of Gram-positive pathogenic bacteria (B. cereus and S. aureus) varied between 1.5 ± 0.5 cm and 4.0 ± 0.2 cm. These findings involve the promise purpose of Bacillus isolated from retted cassava, and this study systematically uncovered the biodiversity and distribution characteristics of retted paste cassava and chikwangue.
基金supported by the National Natural Science Foundation of China(No.41276067)the Air Liquide(China)R&D Co.,Ltd.(No.20200216).
文摘The synergetic effect and underlying mechanism of potassium ferrate(PF)with tea saponin(TS,a biosurfactant)in producing short chain fatty acids(SCFAs)from anaerobic fermentation of waste activated sludge(WAS)were explored in this work.Experimental results showed that 0.2 g PF(g TSS)^(-1)(total suspended solid)combined with 0.02 g TS(g TSS)^(-1) could further improve SCFAs’production,and the maximum SCFAs content reached 2008.7 mg COD L^(-1),which is 1.2 and 4.5 times higher than those with PF and TS individually added,respectively,and 5.3 times higher than that of blank WAS on Day 12.In the model substrates experiments,the degradation rates of bovine serum albumin and dextran with combination of PF and TS were 41.3%±0.1% and 48.5%±0.06%,respectively,on Day 3,which are lower than those in blank WAS(with degradation rates of 72.3%±0.5%and 90.3%±0.3%).It was revealed that the oxidative effect of PF and the solubilization of TS caused more organic matters to be dissolved out from WAS,providing a large number of biodegradable substances for subsequent SCFAs production.While WAS pretreated with the combination of PF and TS,the relative abundances of Firmicutes increased from 6.4%(blank)to 38.6%,and that of Proteobacteria decreased from 41.8%(blank)to 21.8%.The combination of PF and TS promoted the hydrolysis process of WAS by enriching Firmicutes,and then increased acetic acid production by inhibiting Proteobacteria that consumed SCFAs.Meanwhile,at the genus level,acidogenesis bacteria(e.g.,Proteiniclasticum and Petrimonas)were enriched whereas SCFAs consuming bacteria(e.g.,Dokdonella)were inhibited.
文摘The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections.
基金Supported by Basic and Cutting-edge Technique Research of Henan Province(152300410092)Key Program in Science and Technology of Education Department of Henan Province(15A210020,15B180002,15B180016)~~
文摘The growth characteristics of petroleum-degrader BS-8（Bacillus sp.） and the factors influencing its biosurfactant production were tested; the biosurfactant releasing mode of BS-8 was speculated by measuring OD600, surface tension and oil displacement of fermentation broth; and the effects of carbon source, nitrogen source, temperature, p H, and Na Cl concentration on biosurfactant production by BS-8 were observed in this study. The results showed that the biosurfactant releasing mode of BS-8 was growth-correlated, the surface tension of BS-8 fermentation broth declined with the total bacteria increasing, and the oil displacement was positive correlated with biosurfactant content in fermentation broth; and the optimal culture conditions for effective biosurfactant production included： glucose as carbon source,yeast extract as nitrogen source, Na Cl concentration of 2%, p H of 7.0 and temperature at 30 ℃.
文摘Biosurfactant,produced by Pseudomonas aeruginosa BSZ-07,was added to the dee straw decomposing process to enhance the production of reducing sugars.Observed by Fourier Transform InfraRed(FT-IR)and Nuclear Magnetic Resonance(NMR)analysis, the purified biosurfactant was considered as a mixture of RL1 and RL2,which are two different types of rhamnolipids.Two different adding methods,adding the purified rhamnolipid and the on-site production of it were compared.The results showed that 0.5 g/L was the optimum co...
基金The National Natural Science Foundation of China (No. 40272108) and the Doctor Subject Foundation of the Ministry of Educationof China (No. 20040423016)
文摘There were six high diesel oil degrading bacteria strains isolated from the oil contaminated soil that collected from Linzi City. The strain YI was able to produce biosurfactant rhanmolipid when cultivated on diesel oil as carbon source. The critical micelle concentrations （CMC） of rhanmolipid in water and in the soil were measured respectively according to the correlation between the surface tension of the medium and the added rhamnolipid concentration. The results showed that the CMC of rhanmolipid in water was 65 mg/L, and was 185 mg/L in soil. The tests on diesel oil biodegradation were conducted with the addition of different concentrations of rhamnolipid in water and in soil respectively. When 0.01% rhanmolipid was added to water, the diesel oil degradation was enhanced. On the contrary, when the same concentration of rhanmolipid was added to the soil, the degradation of diesel oil was inhibited. The results suggested that the rhamnolipid could enhance the diesel oil biodegradation, indicating that the concentration of rhamnolipid was higher than the corresponding CMC in the medium. Kinetics parameters for the diesel oil biodegradation parameters such as biodegradation constant （λ）, coefficient of correlation （r） and half life （t1/2） in both tests were numerically analyzed in this paper, indicating that the moderate concentration of rhamnolipid in the medium could not only enhance the extent of diesel oil biodegradation but also shorten the time for oil remediation.
基金The work was supported by Tamil Nadu State Council for Science and Technology(TNSCST),Chennai,India(MS-004/TNSCST/SPS/AR/2010-2011)
文摘Objective:To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3.Methods:Halophilic Bacillus sp.BS3 was isolated from solar salt works,identified by 16S rRNA sequencing and was used for screening their biosurfactant production.Characters of the biosurfactant and their anticancer activity were analyzed and performed in mammary epithelial carcinoma cell at different concentrations.Results:The biosurfactant were characterized by TLC,FTIR and GC-MS analysis and identified as lipopeptide type.GC-MS analysis revealed that,the biosurfactant had various compounds including 13Docosenamide.(Z);Mannosamine,9- and N,N,N',N'-tetramethyl.Surprisingly the antiviral activity was found against shrimp white spot syndrome virus(WSSV) by suppressing the viral replication and significantly raised shrimp survival(P<0.01).Anticancer activity performed in the mammary epithelial carcinoma cell at different concentrations of biosurfactants,among the various concentrations of biosurfactants such as 0.000 25,0.002 5,0.025,0.25 and 2.5 μ g,the 0.25 μ g concentration suppressed the cells significantly(P<0.05) to 24.8%.Conclusions:Based on the findings,the present study concluded that,there is a possibility to develop eco-friendly antimicrobial and anticancer drugs from the extremophilic origin.
基金the National Natural Science Foundation of China(No.52130302).
文摘Bioprosthetic heart valves(BHVs)are important for transcatheter valve replacement.Current commercial BHVs on the market are basically porcine or bovine pericardium(BP)crosslinked with glutaraldehyde(GA).Simply applying GA to BHVs can enhance mechanical stability,but cannot alleviate in vivo calcification.In this work,we developed a two-step decellularization(TSD)strategy to modify this biomacromolecular network,in which BP was post-treated,as the second step of decellularization,with a mild biosurfactant n-dodecyl-β-D-maltoside in a mixture of isopropanol and phosphate-buffered saline after the first step of traditional decellularization and GA cross-linking.The TSD-treated BP exhibited not only low cytotoxicity and excellent mechanical properties in vitro,but also low immune responses and significant anticalcification in vivo.After 60 days of subcutaneous implantation in the back of Wistar rats,the calcium content was,as quantified with an inductively coupled plasma optical emission spectrometer,only 1.1µg/mg compared to 138.6µg/mg in the control group without the post-treatment.In addition,collagen fibrils were observed with field emitting scanning electron microscopy(SEM),and the morphology and composition of the calcified sites resulting from in vivo biomineralization were studied with SEM with energy dispersive spectroscopy and also X-ray diffraction.This study proposes a facile yet effective anticalcification strategy for the modification of the bovine pericardial bioprosthetic heart valve,a natural biomacromolecular network.
文摘The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.
基金supported by the National High-technology Research and Development Program(863Program)of China(Grant No.2009AA063504)China National Petroleum Corporation Science&Technology Management Program(2008A-1403)
文摘A Bacillus subtilis strain JA-1 isolated from an oil reservoir was studied. This strain is capable of growth and producing biosurfactant at a temperature of 60 ℃. In nutrient medium it produced biosurfactant which reduced the surface tension from 68.2 mN/m to 28.3 mN/m, with the critical micelle concentration （CMC） of 48 mg/L. The measured surface tension indicated that the biosurfactant possessed stable surface activity at high temperature and a specific range of pH and salt concentrations. The results of thin layer chromatography （TLC） together with FT-IR showed that the metabolic product of strain JA-1 is a lipopeptide biosurfactant. The ability to growth at high temperature and to produce biosurfactant makes strain JA-1 promising for enhanced oil recovery.
基金supported by the National Hi-Tech Research and Development Program (863) of China (No2007AA061101)the National Natural Scientific Foun-dation of China (No 20377024)
文摘The objective of this study was to examine the effect of biosurfactant on the sorption of phenanthrene （PHE） onto the original or HzO2-treated black loamy soil （typic isohumisols） and red sandy soil （typic ferralisols）. The sorption isotherms were performed with the original and ＂soft＂ carbon-removed soils in the presence and absence of biosurfactant （200 mg/L）. The sorption and degradation of biosurfactant were investigated. The result showed that organic matter played an important role in PHE sorption onto the black loamy and red sandy soils, and the PHE sorption isotherms on the ＂soft＂ carbon-removed soils exhibited more nonlinearity than those on the original soils. The values of partition coefficient （Kd） on the original black loamy soil with or without 200 mg/L biosurfactant were 181.6 and 494.5 mL/g, respectively. Correspondingly, in the red sandy soil, Kd was 246.4 and 212.8 mL/g in the presence or absence of biosurfactant, respectively. The changes of Kd suggested that biosurfactant inhibited PHE sorption onto the black loamy soil, but facilitated PHE sorption onto the red sandy soil. The nonlinearity of PHE sorption isotherm was decreased in the presence of biosurfactant. Site specific sorption might occur during PHE sorption onto both the original and the ＂soft＂ carbon-removed soils in the presence of biosurfactant. It was noted that biosurfactant could also be sorbed onto soils. The maximal sorption capacity of the red sandy soil for biosurfactant was （76.9 ± 0.007） μg/g, which was 1.31 times that of black loamy soil. Biosurfactant was degraded quickly in the two selected soils, and 92% of biosurfactant were mineralized throughout the incubation experiment for 7 d. It implied that biosurfactant should be added frequently when the remediation of polycyclic aromatic hydrocarbon （PAH）-contaminated soils was conducted through PAH desorption approach facilitated by biosurfactant.
基金Project(IRT0719) supported by the Program for Changjiang Scholars and Innovative Research Team in University of China Project (2004AA649370) supported by the National High-Tech Research and Development Program of China+1 种基金 Projects(50425927, 50225926) supported by the Natural Foundation for Distinguished Young Scholars Project(2007F3102) supported by Technology Foundation for Creative Young Scholars of Fujian Province, China
文摘The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration.
文摘One possible application for the excess of glycerol, which is an exceeding byproduct in biodiesel industry, was used as carbon and energy sources for bioproducts synthesis. This work aims to evaluate biosurfactant production from glycerol by Pseudomonas aeruginosa EQ 109 isolated from crude oil-contaminated soil. Factorial design 2^3 was utilized to optimize the amount of biosurfactant produced, by using pH （A）, initial biomass concentration （B）, and initial glycerol concentration （C） as independent factors. The experiments were carried out in flasks containing 100 mL of mineral medium. Biosurfactant production was monitored by increase of the emulsification of aviation kerosene （E24） and surface tension reduction （STr）. The results have shown that, at pH = 7.0, in order to increase E24, variables as B and C are the most influential, leading to a maximum value of E24 = 79%, as well as for an increase of GC （GCmax = 49%）. STR was the variable with the best correlation factor for the proposed linear model （R2=0.96） and its maximum value was 48%. Xfwas not significant to the model, although it was influenced by pH and C, with C = 40g/L （Xfmax = 4.56 g/L）.
文摘Biosurfactants are biomolecules produced by microorganisms, which possess several advantages over their chemical counterparts. Production can be cost-effective if renewable wastes are utilized as substrates. In this study, optimization of biosurfactant production by <i>Pseudomonas aeruginosa</i> strain CGA1 was carried out using response surface methodology. The conventional “One factor at a time” method of optimization was initially adopted to ascertain the impact of different renewable wastes on biosurfactant production. Four independent variables were tested: carbon and nitrogen concentration, medium volume, and inoculum size. Biosurfactant production was based on the emulsification index measurement. Results indicated that the preferred carbon source by the isolate was sugar cane molasses. A 2.31-fold increase in biosurfactant yield and emulsification index of 96.3% ± 0.75% under optimized cultural conditions of 20 g/L of molasses, 5 g/L of sodium nitrate, 1.93 ml inoculum size and 60 ml medium volume in 250 ml conical flask were obtained. The regression coefficient (R<sup>2</sup>) value of 84.15% implied adequate fitness of the model. The surface tension of distilled water was reduced from 72.1 mN/m to 35.0 ± 0.0 mN/m, and critical micelle concentration was attained at 60 mg·L<sup>-1</sup>. FTIR and GC-MS analysis indicated that the biosurfactant was a lipopeptide having characteristic lipid and peptide peak values. This study proves that the sole use of agro-industrial wastes for the production of biosurfactant is very efficient, and ensures the economic feasibility of biosurfactant production.
基金supported by the Doctoral School in“Scienze Ambientali:Ambiente Marino e Risorse”of theUniversity of Messina,Italy
文摘Joostella strains are emerging candidates for biosurfactant production. Here such ability was analyzed for Joostella strain A8 in comparison with Alcanivorax strain A53 and Pseudomonas strain A6, all previously isolated from hydrocarbon enrichment cultures made of polychaete homogenates. In pure cultures Joostella sp. A8 showed the highest stable emulsion percentage（78.33%）, hydrophobicity rate（62.67%）, and an optimal surface tension reduction during growth in mineral medium supplemented with diesel oil（reduction of about 12 mN/m）, thus proving to be highly competitive with Alcanivorax and Pseudomonas strains. During growth in pure culture different level of biodegradation were detected for Alcanivorax strain A53（52.7%）,Pseudomonas strain A6（38.2%） and Joostella strain A8（26.8%）. When growing in consortia,isolates achieved similar abundance values, with the best efficiency that was observed for the Joostella-Pseudomonas co-culture. Gas-chromatographic analysis revealed an increase in the biodegradation efficiency in co-cultures（about 90%）, suggesting that the contemporary action of different bacterial species could improve the process. Results were useful to compare the efficiencies of well-known biosurfactant producers（i.e. Pseudomonas and Alcanivorax representatives） with a still unknown biosurfactant producer, i.e. Joostella, and to confirm them as optimal biosurfactant-producing candidates.
基金Supported by Key Science and Technology Program of Henan Province(132102310253,122102310350)Natural Science Research Program of Education Department of Henan Province(15A210020,12A180008)
文摘After incubation for 6 -30 h, with the rapid increase of bacterial cell number, surface tension of bacterium BS-8 was reduced sharply from 63.2 mN/m to 39.4 mN/m. The production of biosurfactants by BS-8 was growth-dependent. Using glucose as the carbon source, bacterium BS-8 was incubated. Based on centrifugation, precipitation and chromogenie reaction of the culture solution, results indicated that the biosurfactants belonged to lipopeptides. The yield of biosurfaetants isolated and purified from the culture solution was 0.58 g/L, and the critical micelle concentration （CMC） was 90 mg,/L. Under conditions of pH 4 -9, tem- perature 20 -70 ℃, NaCl concentration 1% -6%, biosurfactants predueed by BS-8 exhibited the highest stability.
文摘This work reports detergents production using biological surfactants, microbiologically synthesized, and compares its foaming power and emulsification capacity to those presented by a petroleum based surfactant. Both used microorganisms were capable to produce surfactants, been able to emulsify oil/water mixtures and cause decrease of surface tension of water. The biosurfactant produced from Yarrowia lipolytica has a critical micelle concentration lower than that obtained from Pseudomonas aeruginosa （10 and 30 mg·Lt, respectively）, but the later showed better results in foaming power and emulsification experiments, similar to the synthetic detergent.
文摘Biosurfactants are biologically active metabolites, and the efficiency of direct screening of new biosurfactants from nature using traditional methods is low, which should be enhanced in the following studies by adopting advanced biotechnologies. Rapid development and wide application of microbial culture independent methods, such as metagenomics, metatranscriptomics, metaproteomics and metabonomics, etc., contributes to quickly and precisely screening of novel biological surfactants. We mainly represented the current status of research and applications of biosurfactants in the remediation of petrochemical polluted environment, and also prospected avenues for future research.
