In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composi...In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry.Oxygen and high temperatures(22–25°C) significantly reduced the stability of astaxanthin esters.Corn germ oil and antioxidants(ascorbic acid and vitamin E)failed to protect astaxanthin from oxidation,and actually significantly increased the instability of astaxanthin.A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage.During storage,the relative amounts of free astaxanthin and astaxanthin monoesters declined,while the relative amount of astaxanthin diesters increased.Thus,the ratio of astaxanthin diester to monoester increased,and this ratio could be used to indicate if astaxanthin esters have been properly preserved.If the ratio is greater than 0.2,it suggests that the decrease in astaxanthin content could be higher than 20%.Our results show that storing algal powder from H.pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H.pluvialis.This storage method can produce an astaxanthin preservation rate of at least 80%after 96 weeks of storage.展开更多
[Objective] The optimal craft of preparing conjugated linoleic acid from corn germ oil by dint of microwave method was studied. [Meth- od] Microwave power, microwave mode of action, the amount of catalyst and solvent ...[Objective] The optimal craft of preparing conjugated linoleic acid from corn germ oil by dint of microwave method was studied. [Meth- od] Microwave power, microwave mode of action, the amount of catalyst and solvent were selected for single-factor-experiment. Then, based on the single-factor-experiment, the catalyst and solvent amount, and microwave function time were chosen for orthogonal experiment so as to deter- mine the optimal craft of preparing CLA from corn germ oil. UV absorption spectra and infrared absorption spectrum were used to analyse the struc- tural features of natural corn germ oil and CLA. [Resalt] The optimal preparation condition was as follow: the catalyst was 0.6 times heavier than oil, solvent was 3 times heavier than oil weight, microwave worked for ten minutes. Under the optimal condition, CLA was 56.3% and conversion rate was 99.47 %. The results indicated that non-conjugated double bonds of linoleic acid can be isomerized and changed into conjugated double bonds under the conditions of microwave irradiation,[ Conduslon] The study provided a new way for the preparation of CLA.展开更多
A hydrocarbon degrading bacterium KL2-13 was isolated from ten sites of oil contaminated soil in the Karamay oilfield. It was identified as the Bacillusfusiformis sp. bacterium based on its morphological and physiolog...A hydrocarbon degrading bacterium KL2-13 was isolated from ten sites of oil contaminated soil in the Karamay oilfield. It was identified as the Bacillusfusiformis sp. bacterium based on its morphological and physiological characteristics and the 16S rDNA sequence analysis. The factors influencing the hydrocarbon degradation by the bacterium KL2-13 were determined. The test results have showed that the hydrocarbon degrading bacterium KL2-13 requires an optimum pH range of 6-8, and the optimum inoculation quantity is 3%. The low-concentration metal ions Fe^2+, Mg^2+ and Ca^2+can improve the degradation ability of the bacteria KL2-13. A too low concentration of Tween-80 does not show obvious promotion to the degrading bacterium KL2-13, and an excessively high concentration can decrease the degradation ability of the bacterium, the best dosage of which is 2%. The hydrocarbon degrading rate reached 59.07%4-0.37% under the optimum culture conditions.展开更多
Phytoremediation shows promise as an alternative low-cost to most remediation methods. This study evaluated the germination of six crops, including four mutant lines of barley (Hordium vulgate L.) (1-9-3, 150-2-3, ...Phytoremediation shows promise as an alternative low-cost to most remediation methods. This study evaluated the germination of six crops, including four mutant lines of barley (Hordium vulgate L.) (1-9-3, 150-2-3, 1-1-200 and 150-1-5), wheat (Triticum aestivum L.) and garden cress (Lipidium sativum L.). This experiment was conducted in laboratory at room temperature. Oil extracted from crude oil contaminated soil was added to sand used in different concentrations (0%, 2%, 4%, 6%, 8% and 10%). 10 seeds of each crop were sown in ptri-dishes with different treatments separately. For Each treatment four replicates were used in completely randomized design, germination percent was calculated, after one week, shoot and root length were measured. Data were statistically analyzed using MINTAB version 12. The results show that barley mutant line (150-2-3) was significantly different from other entries in germination percent, shoot and root length except mutant line 150-1-5 in germination percent. Results demonstrated that the mutant line 150-2-3 was promising to remediate crude oil contaminated soil.展开更多
In this study, a thermophilic oil-degrading bacterial consortium KO8-2 growing within the temperature range of 45--65℃ (with 55℃ being the optimum temperature) was isolated from oil-contaminated soil of Karamay in...In this study, a thermophilic oil-degrading bacterial consortium KO8-2 growing within the temperature range of 45--65℃ (with 55℃ being the optimum temperature) was isolated from oil-contaminated soil of Karamay in Xinjiang, China. Denaturing gradient gel electrophoresis (DGGE) showed that there were nine strains included in KO8-2, which originated from the genera of Bacillus, Geobacillus and Clostridium. They all belonged to thermophilic bacteria, and had been previously proved as degraders of at least one petroleum fraction. The crude oil degraded by KO8-2 was analyzed by infrared spectrophotometry, hydrocarbon group type analysis and gas chromatography. The results indicated that the bacterial consortium KO8-2 was able to utilize 64.33% of saturates, 27.06% of aromatics, 13.24% of resins and the oil removal efficiency reached up to 58.73% at 55 ~C when the oil concentration was 10 g/L. Detailed analysis showed that KO8-2 was able to utilize the hydrocarbon components before C19, and the n-alkanes ranging from C20--C33 were signifi- cantly degraded. The ratios of nC17/Pr and nC18/Ph were 3.12 and 3.87, respectively, before degradation, whereas after degradation the ratios reduced to 0.21 and 0.38, respectively. Compared with the control sample, the oil removal efficiency in KO8-2 composting reactor reached 50.12% after a degradation duration of 60 days.展开更多
In the present work, we investigated the effect of Mucuna deeringiana defatted bran on seed germination of soybean (Glycine max L. Merrill). For this, the defatted bran was obtained from different operational condit...In the present work, we investigated the effect of Mucuna deeringiana defatted bran on seed germination of soybean (Glycine max L. Merrill). For this, the defatted bran was obtained from different operational conditions using CO2 under pressurized conditions as solvent. Oil extractions were carried out in a laboratorial scale unit at temperatures ranging from 310 to 330 K, pressure from 15 to 25 MPa and solvent flow set in 3 mL min^-1. The experiment was conducted in a germination chamber (25℃, 12:12 h light:dark photoperiod), and the germination rate and germination speed index (GSI) were evaluated for seven days. The results showed that the oil extraction with supercritical CO2 concentrates the allelochemical L-3,4-dihydroxyphenylalanine (L-DOPA) in bran with levels from 1.86% to 4.65%. Subsequent experiments revealed that the rate of soybean seed germination was not affected by defatted bran whereas the GSI increased significantly after treatment. In brief, we concluded that the extraction process with supercritical CO2 is efficient to obtain L-DOPA of Mucuna, which influences the soybean seed germination.展开更多
基金Supported by the Yunnan Provincial Sciences and Technology Department,China(No.2007AD009)the National Natural Science Foundation of China(No.31272680)the Ministry of Science and Technology of China(No.2013AA065805)
文摘In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry.Oxygen and high temperatures(22–25°C) significantly reduced the stability of astaxanthin esters.Corn germ oil and antioxidants(ascorbic acid and vitamin E)failed to protect astaxanthin from oxidation,and actually significantly increased the instability of astaxanthin.A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage.During storage,the relative amounts of free astaxanthin and astaxanthin monoesters declined,while the relative amount of astaxanthin diesters increased.Thus,the ratio of astaxanthin diester to monoester increased,and this ratio could be used to indicate if astaxanthin esters have been properly preserved.If the ratio is greater than 0.2,it suggests that the decrease in astaxanthin content could be higher than 20%.Our results show that storing algal powder from H.pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H.pluvialis.This storage method can produce an astaxanthin preservation rate of at least 80%after 96 weeks of storage.
文摘[Objective] The optimal craft of preparing conjugated linoleic acid from corn germ oil by dint of microwave method was studied. [Meth- od] Microwave power, microwave mode of action, the amount of catalyst and solvent were selected for single-factor-experiment. Then, based on the single-factor-experiment, the catalyst and solvent amount, and microwave function time were chosen for orthogonal experiment so as to deter- mine the optimal craft of preparing CLA from corn germ oil. UV absorption spectra and infrared absorption spectrum were used to analyse the struc- tural features of natural corn germ oil and CLA. [Resalt] The optimal preparation condition was as follow: the catalyst was 0.6 times heavier than oil, solvent was 3 times heavier than oil weight, microwave worked for ten minutes. Under the optimal condition, CLA was 56.3% and conversion rate was 99.47 %. The results indicated that non-conjugated double bonds of linoleic acid can be isomerized and changed into conjugated double bonds under the conditions of microwave irradiation,[ Conduslon] The study provided a new way for the preparation of CLA.
基金supports provided by the Science Research and Technology Developing Program, CNPC (2008D-4704-2): "Microbial remediation technology of high-temperature and arid oil polluted soil"
文摘A hydrocarbon degrading bacterium KL2-13 was isolated from ten sites of oil contaminated soil in the Karamay oilfield. It was identified as the Bacillusfusiformis sp. bacterium based on its morphological and physiological characteristics and the 16S rDNA sequence analysis. The factors influencing the hydrocarbon degradation by the bacterium KL2-13 were determined. The test results have showed that the hydrocarbon degrading bacterium KL2-13 requires an optimum pH range of 6-8, and the optimum inoculation quantity is 3%. The low-concentration metal ions Fe^2+, Mg^2+ and Ca^2+can improve the degradation ability of the bacteria KL2-13. A too low concentration of Tween-80 does not show obvious promotion to the degrading bacterium KL2-13, and an excessively high concentration can decrease the degradation ability of the bacterium, the best dosage of which is 2%. The hydrocarbon degrading rate reached 59.07%4-0.37% under the optimum culture conditions.
文摘Phytoremediation shows promise as an alternative low-cost to most remediation methods. This study evaluated the germination of six crops, including four mutant lines of barley (Hordium vulgate L.) (1-9-3, 150-2-3, 1-1-200 and 150-1-5), wheat (Triticum aestivum L.) and garden cress (Lipidium sativum L.). This experiment was conducted in laboratory at room temperature. Oil extracted from crude oil contaminated soil was added to sand used in different concentrations (0%, 2%, 4%, 6%, 8% and 10%). 10 seeds of each crop were sown in ptri-dishes with different treatments separately. For Each treatment four replicates were used in completely randomized design, germination percent was calculated, after one week, shoot and root length were measured. Data were statistically analyzed using MINTAB version 12. The results show that barley mutant line (150-2-3) was significantly different from other entries in germination percent, shoot and root length except mutant line 150-1-5 in germination percent. Results demonstrated that the mutant line 150-2-3 was promising to remediate crude oil contaminated soil.
基金the support provided by the Research&Technology Development Project of China National Petroleum Corporation(No.2008D-4704-2)
文摘In this study, a thermophilic oil-degrading bacterial consortium KO8-2 growing within the temperature range of 45--65℃ (with 55℃ being the optimum temperature) was isolated from oil-contaminated soil of Karamay in Xinjiang, China. Denaturing gradient gel electrophoresis (DGGE) showed that there were nine strains included in KO8-2, which originated from the genera of Bacillus, Geobacillus and Clostridium. They all belonged to thermophilic bacteria, and had been previously proved as degraders of at least one petroleum fraction. The crude oil degraded by KO8-2 was analyzed by infrared spectrophotometry, hydrocarbon group type analysis and gas chromatography. The results indicated that the bacterial consortium KO8-2 was able to utilize 64.33% of saturates, 27.06% of aromatics, 13.24% of resins and the oil removal efficiency reached up to 58.73% at 55 ~C when the oil concentration was 10 g/L. Detailed analysis showed that KO8-2 was able to utilize the hydrocarbon components before C19, and the n-alkanes ranging from C20--C33 were signifi- cantly degraded. The ratios of nC17/Pr and nC18/Ph were 3.12 and 3.87, respectively, before degradation, whereas after degradation the ratios reduced to 0.21 and 0.38, respectively. Compared with the control sample, the oil removal efficiency in KO8-2 composting reactor reached 50.12% after a degradation duration of 60 days.
文摘In the present work, we investigated the effect of Mucuna deeringiana defatted bran on seed germination of soybean (Glycine max L. Merrill). For this, the defatted bran was obtained from different operational conditions using CO2 under pressurized conditions as solvent. Oil extractions were carried out in a laboratorial scale unit at temperatures ranging from 310 to 330 K, pressure from 15 to 25 MPa and solvent flow set in 3 mL min^-1. The experiment was conducted in a germination chamber (25℃, 12:12 h light:dark photoperiod), and the germination rate and germination speed index (GSI) were evaluated for seven days. The results showed that the oil extraction with supercritical CO2 concentrates the allelochemical L-3,4-dihydroxyphenylalanine (L-DOPA) in bran with levels from 1.86% to 4.65%. Subsequent experiments revealed that the rate of soybean seed germination was not affected by defatted bran whereas the GSI increased significantly after treatment. In brief, we concluded that the extraction process with supercritical CO2 is efficient to obtain L-DOPA of Mucuna, which influences the soybean seed germination.