The ability of Yarrowia lipolytica W29 immobilized by calcium alginate to degrade oil and chemical oxygen demand (COD) was examined. The degradation rules of oil and COD by immobilized cells with the cell density of...The ability of Yarrowia lipolytica W29 immobilized by calcium alginate to degrade oil and chemical oxygen demand (COD) was examined. The degradation rules of oil and COD by immobilized cells with the cell density of 6.65 × 10^6 CFU/mL degraded 2000 mg/L oil and 2000 mg/L COD within 50 h at 30℃ (pH 7.0, 150 r/min), similarly to those of free cells, and the degradation efficiencies of oil and COD by immobilized cells were above 80%, respectively. The factors affecting oil and COD degradation by immobilized cells were investigated, the results showed that immobilized cells had high thermostability compared to that of free cells, and substrate concentration significantly affected degrading ability of immobilized cells. Storage stability and reusability tests revealed that the oil degradation ability of immobilized cells was stable after storing at 4~C for 30 d and reuse for 12 times, respectively, the COD degradation rate of immobilized cells was also maintained 82% at the sixth cycle. These results suggested that immobilized Y lipolytica might be applicable to a wastewater treatment system for the removal of oil and COD.展开更多
The production of extra cellular lipase in Solid State Fermentation (SSF) using Yarrowia lipolytica NCIM 3589 with Palm Kernal cake (Elaeis guineensis) has been studied. Different parameters such as incubation time, i...The production of extra cellular lipase in Solid State Fermentation (SSF) using Yarrowia lipolytica NCIM 3589 with Palm Kernal cake (Elaeis guineensis) has been studied. Different parameters such as incubation time, inoculum level, initial moisture content, carbon level and nitrogen level of the medium were optimized. Screening of various process variables has been accomplished with the help of Plackett-Burman design. The maximum lipase activity of 18.58 units per gram of dry fermented substrate (U/gds) was observed with the substrate of Palm Kernal cake in four days of fermentation.展开更多
3,4-Dihydroxy L-phenylalanine(L-DOPA)is considered a potent drug for the treatment of Parkinson disease.Physical and nutritional parameters where optimized by using Yarrowia lipolytica-NCIM 3450 to accomplished the hi...3,4-Dihydroxy L-phenylalanine(L-DOPA)is considered a potent drug for the treatment of Parkinson disease.Physical and nutritional parameters where optimized by using Yarrowia lipolytica-NCIM 3450 to accomplished the highest production of L-DOPA.Screenings of critical components were completed by using a Plackett–Burman design,while further optimization was carried out using the Box–Behnken design.The optimized factor levels predicted by the model were pH 6.1,1.659 g L^(-1)yeast extract,1.491 g L^(-1)L-tyrosine and 0.0290 g L^(-1)CuSO4.The predicted yield of L-DOPA with these levels was 1.319 g L^(-1),while actual yield obtained was 1.273 g L^(-1).The statistical analysis revealed that model is significant with F value 19.55 and R2 value 0.9514.This process resulted in a 3.594-fold increase in the yield of LDOPA.L-DOPA was confirmed by HPTLC and HPLC analysis.Thus,Yarrowia lipolytica-NCIM 3450 has potential to be a new source for the production of L-DOPA.展开更多
The bioconversion of the hydrophobic and volatile limonene to perillic acid, a potential anticancer agent, by the yeast Yarrowia lipolytica was studied in two steps. Firstly, experimental design was used for process o...The bioconversion of the hydrophobic and volatile limonene to perillic acid, a potential anticancer agent, by the yeast Yarrowia lipolytica was studied in two steps. Firstly, experimental design was used for process optimization using high-purity limonene as substrate and secondly orange essential oil containing 89.1% limonene was used as substrate under the previously optimized conditions. Limonene concentration and pH were identified by fractional factorial design as significant factors and were optimized by central composite design. Under optimized process conditions (0.16% (v/v) limonene;pH 6.9), the 24 h biotransformation process resulted in the accumulation of 0.368 g·L-1 of perillic acid corresponding to a molar yield of 23.1%. A subsequent substrate addition under the same reaction conditions doubled perillic acid concentration to 0.793 g·L-1 and a molar yield of 24.2%. The use of orange essential oil under the optimized reaction conditions increased both perillic acid accumulation and yield to 0.872 g·L-1 and 29.7%, respectively. The robustness of Y. lipolytica allowed the efficient biotransformation of a crude by-product of the citrus industry into a valuable fine chemical.展开更多
Growth rate of Yarrowia lipolytica NCIM 3589 was observed in a fermentation medium consisting of peptone, yeast extract, sodium chloride. Logistic equation was fitted to the growth data (time vs. biomass concentration...Growth rate of Yarrowia lipolytica NCIM 3589 was observed in a fermentation medium consisting of peptone, yeast extract, sodium chloride. Logistic equation was fitted to the growth data (time vs. biomass concentration) and compared with the prediction given by Artificial Neural Networks (ANN). ANN was found to be superior in describing growth characteristics. A single MATLAB programme is developed to fit the growth data by logistic equation and ANN.展开更多
Although Yarrowia lipolytica is an important host strain, there have so far been few studies on the production of glutathione by the strain. We therefore performed a study to obtain an improved strain of Y. lipolytica...Although Yarrowia lipolytica is an important host strain, there have so far been few studies on the production of glutathione by the strain. We therefore performed a study to obtain an improved strain of Y. lipolytica ATCC20688, which could produce a high yield of glutathione. First, the capability of glutathione production in the ATCC20688 strain was estimated. In comparison with other yeasts, the yield of this strain was higher than those in Pichia strains. Furthermore, this strain could produce glutathione by assimilating sodium oleate. We next performed mutation and gene cloning to improve the yield. After the yield of glutathione was improved in the isolated methylglyoxal-resistant mutant (MGR3), the glutathione synthetase gene was cloned into the MGR3 strain. By using this recombinant strain, we could reach the maximum yield and intracellular content of glutathione of 54 mg/L-medium and 30 mg/g-dry cell weight, respectively.展开更多
Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel,but its microbial biosynthesis yield is very low.In this study,we employed Yarrowia lipolytica as a microbial hos...Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel,but its microbial biosynthesis yield is very low.In this study,we employed Yarrowia lipolytica as a microbial host to produce taxadiene.First,a“push–pull”strategy was adopted to increase taxadiene production by 234%.Then taxadiene synthase was fused with five solubilizing tags respectively,leading a maximum increase of 62.3%in taxadiene production when fused with SUMO.Subsequently,a multi-copy iterative integration method was used to further increase taxadiene titer,achieving the maximum titer of 23.7 mg/L in shake flask culture after three rounds of integration.Finally,the taxadiene titer was increased to 101.4 mg/L by optimization of the fed-batch fermentation conditions.This is the first report of taxadiene biosynthesis accomplished in Y.lipolytica,serving as a good example for the sustainable production of taxadiene and other terpenoids in this oleaginous yeast.展开更多
基金supported by the National Key Technologies R & D Program of China (No. 2007BAC23B01)the Program of Department of Education, Jiangxi Province, China (No. 2007-41).
文摘The ability of Yarrowia lipolytica W29 immobilized by calcium alginate to degrade oil and chemical oxygen demand (COD) was examined. The degradation rules of oil and COD by immobilized cells with the cell density of 6.65 × 10^6 CFU/mL degraded 2000 mg/L oil and 2000 mg/L COD within 50 h at 30℃ (pH 7.0, 150 r/min), similarly to those of free cells, and the degradation efficiencies of oil and COD by immobilized cells were above 80%, respectively. The factors affecting oil and COD degradation by immobilized cells were investigated, the results showed that immobilized cells had high thermostability compared to that of free cells, and substrate concentration significantly affected degrading ability of immobilized cells. Storage stability and reusability tests revealed that the oil degradation ability of immobilized cells was stable after storing at 4~C for 30 d and reuse for 12 times, respectively, the COD degradation rate of immobilized cells was also maintained 82% at the sixth cycle. These results suggested that immobilized Y lipolytica might be applicable to a wastewater treatment system for the removal of oil and COD.
文摘The production of extra cellular lipase in Solid State Fermentation (SSF) using Yarrowia lipolytica NCIM 3589 with Palm Kernal cake (Elaeis guineensis) has been studied. Different parameters such as incubation time, inoculum level, initial moisture content, carbon level and nitrogen level of the medium were optimized. Screening of various process variables has been accomplished with the help of Plackett-Burman design. The maximum lipase activity of 18.58 units per gram of dry fermented substrate (U/gds) was observed with the substrate of Palm Kernal cake in four days of fermentation.
文摘3,4-Dihydroxy L-phenylalanine(L-DOPA)is considered a potent drug for the treatment of Parkinson disease.Physical and nutritional parameters where optimized by using Yarrowia lipolytica-NCIM 3450 to accomplished the highest production of L-DOPA.Screenings of critical components were completed by using a Plackett–Burman design,while further optimization was carried out using the Box–Behnken design.The optimized factor levels predicted by the model were pH 6.1,1.659 g L^(-1)yeast extract,1.491 g L^(-1)L-tyrosine and 0.0290 g L^(-1)CuSO4.The predicted yield of L-DOPA with these levels was 1.319 g L^(-1),while actual yield obtained was 1.273 g L^(-1).The statistical analysis revealed that model is significant with F value 19.55 and R2 value 0.9514.This process resulted in a 3.594-fold increase in the yield of LDOPA.L-DOPA was confirmed by HPTLC and HPLC analysis.Thus,Yarrowia lipolytica-NCIM 3450 has potential to be a new source for the production of L-DOPA.
文摘The bioconversion of the hydrophobic and volatile limonene to perillic acid, a potential anticancer agent, by the yeast Yarrowia lipolytica was studied in two steps. Firstly, experimental design was used for process optimization using high-purity limonene as substrate and secondly orange essential oil containing 89.1% limonene was used as substrate under the previously optimized conditions. Limonene concentration and pH were identified by fractional factorial design as significant factors and were optimized by central composite design. Under optimized process conditions (0.16% (v/v) limonene;pH 6.9), the 24 h biotransformation process resulted in the accumulation of 0.368 g·L-1 of perillic acid corresponding to a molar yield of 23.1%. A subsequent substrate addition under the same reaction conditions doubled perillic acid concentration to 0.793 g·L-1 and a molar yield of 24.2%. The use of orange essential oil under the optimized reaction conditions increased both perillic acid accumulation and yield to 0.872 g·L-1 and 29.7%, respectively. The robustness of Y. lipolytica allowed the efficient biotransformation of a crude by-product of the citrus industry into a valuable fine chemical.
文摘Growth rate of Yarrowia lipolytica NCIM 3589 was observed in a fermentation medium consisting of peptone, yeast extract, sodium chloride. Logistic equation was fitted to the growth data (time vs. biomass concentration) and compared with the prediction given by Artificial Neural Networks (ANN). ANN was found to be superior in describing growth characteristics. A single MATLAB programme is developed to fit the growth data by logistic equation and ANN.
文摘Although Yarrowia lipolytica is an important host strain, there have so far been few studies on the production of glutathione by the strain. We therefore performed a study to obtain an improved strain of Y. lipolytica ATCC20688, which could produce a high yield of glutathione. First, the capability of glutathione production in the ATCC20688 strain was estimated. In comparison with other yeasts, the yield of this strain was higher than those in Pichia strains. Furthermore, this strain could produce glutathione by assimilating sodium oleate. We next performed mutation and gene cloning to improve the yield. After the yield of glutathione was improved in the isolated methylglyoxal-resistant mutant (MGR3), the glutathione synthetase gene was cloned into the MGR3 strain. By using this recombinant strain, we could reach the maximum yield and intracellular content of glutathione of 54 mg/L-medium and 30 mg/g-dry cell weight, respectively.
基金supported by the National Key Research and Development Program of China(2019YFA0905000)the National Natural Science Foundation of China(21871085 and 31971380)the Fundamental Research Funds for the Central Universities(222201714026).
文摘Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel,but its microbial biosynthesis yield is very low.In this study,we employed Yarrowia lipolytica as a microbial host to produce taxadiene.First,a“push–pull”strategy was adopted to increase taxadiene production by 234%.Then taxadiene synthase was fused with five solubilizing tags respectively,leading a maximum increase of 62.3%in taxadiene production when fused with SUMO.Subsequently,a multi-copy iterative integration method was used to further increase taxadiene titer,achieving the maximum titer of 23.7 mg/L in shake flask culture after three rounds of integration.Finally,the taxadiene titer was increased to 101.4 mg/L by optimization of the fed-batch fermentation conditions.This is the first report of taxadiene biosynthesis accomplished in Y.lipolytica,serving as a good example for the sustainable production of taxadiene and other terpenoids in this oleaginous yeast.