After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra haitanensis, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to...After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra haitanensis, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to determine the effectiveness of each antibiotic in eliminating contaminating microorganisms. Five of 12 antibiotics tested were selected and used to produce the axenic cultures in this study, which showed that 200 μg/mL streptomycin, 250 μg/mL penicillin, 252 μg/mL kanamycin, 30 μg/mL neomycin, 200 μg/mL chloramphenicol were effective concentrations for eliminating microorganisms from conchocelis when antibiotics were added singly step by step; whereas simultaneous combination of 150 μg/mL streptomycin, 250 (or 350) μg/mL penicillin, 150 (or 250) μg/mL kanamycin, 70 μg/mL neomycin and 200 μg/mL chloramphenicol was also effective for producing the axenic cultures. However, it seemed that the treatments with antibiotics applied individually were more feasible than those with all antibiotics added at the same time. This may be due to the combined inhibiting effect of antibiotics on the growth and development of conchocelis.展开更多
Axenic microalgal strains are highly valued in diverse microalgal studies and applications. Antibiotics, alone or in combination, are often used to avoid bacterial contamination during microalgal isolation and culture...Axenic microalgal strains are highly valued in diverse microalgal studies and applications. Antibiotics, alone or in combination, are often used to avoid bacterial contamination during microalgal isolation and culture. In our preliminary trials, we found that many microalgae ceased growing in antibiotics at extremely high concentrations but could resume growth quickly when returned to an antibiotics-free liquid medium and formed colonies when spread on a solid medium. We developed a simple and highly efficient method of obtaining axenic microalgal cultures based on this observation. First, microalgal strains of different species or strains were treated with a mixture of ampicillin, gentamycin sulfate, kanamycin, neomycin and streptomycin （each at a concentration of 600 mg/L） for 3 days; they were then transferred to antibiotics-free medium for 5 days; and finally they were spread on solid f/2 media to allow algal colonies to form. With this method, five strains ofNannochloropsis sp. （Eustigmatophyceae）, two strains of Cylindrotheca sp. （Bacillariophyceae）, two strains of Tetraselmis sp. （Chlorodendrophyceae） and one strain ofAmphikrikos sp. （Trebouxiophyceae） were purified successfully. The method shows promise for batch- purifying microalgal cultures.展开更多
法国Axens公司开发的多产丙烯渣油流化催化裂化（RFCC）“PetroRiser”新技术工业应用。这项新技术是FCC联盟中的一部分（FCC联盟由Axens、TheShawGroup、Total S A、IFP四家公司联合组建），采用该新技术的工业化许可项目定于2008年7...法国Axens公司开发的多产丙烯渣油流化催化裂化（RFCC）“PetroRiser”新技术工业应用。这项新技术是FCC联盟中的一部分（FCC联盟由Axens、TheShawGroup、Total S A、IFP四家公司联合组建），采用该新技术的工业化许可项目定于2008年7月公布。展开更多
文摘After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra haitanensis, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to determine the effectiveness of each antibiotic in eliminating contaminating microorganisms. Five of 12 antibiotics tested were selected and used to produce the axenic cultures in this study, which showed that 200 μg/mL streptomycin, 250 μg/mL penicillin, 252 μg/mL kanamycin, 30 μg/mL neomycin, 200 μg/mL chloramphenicol were effective concentrations for eliminating microorganisms from conchocelis when antibiotics were added singly step by step; whereas simultaneous combination of 150 μg/mL streptomycin, 250 (or 350) μg/mL penicillin, 150 (or 250) μg/mL kanamycin, 70 μg/mL neomycin and 200 μg/mL chloramphenicol was also effective for producing the axenic cultures. However, it seemed that the treatments with antibiotics applied individually were more feasible than those with all antibiotics added at the same time. This may be due to the combined inhibiting effect of antibiotics on the growth and development of conchocelis.
基金Supported by the National Basic Research Program of China(973 Program)(No.2011CB200901)the National Technical Supporting Project Foundation(No.2011BAD14B01)the National High Technology Research and Development Program of China(863 Program)(No.2013AA065801)
文摘Axenic microalgal strains are highly valued in diverse microalgal studies and applications. Antibiotics, alone or in combination, are often used to avoid bacterial contamination during microalgal isolation and culture. In our preliminary trials, we found that many microalgae ceased growing in antibiotics at extremely high concentrations but could resume growth quickly when returned to an antibiotics-free liquid medium and formed colonies when spread on a solid medium. We developed a simple and highly efficient method of obtaining axenic microalgal cultures based on this observation. First, microalgal strains of different species or strains were treated with a mixture of ampicillin, gentamycin sulfate, kanamycin, neomycin and streptomycin （each at a concentration of 600 mg/L） for 3 days; they were then transferred to antibiotics-free medium for 5 days; and finally they were spread on solid f/2 media to allow algal colonies to form. With this method, five strains ofNannochloropsis sp. （Eustigmatophyceae）, two strains of Cylindrotheca sp. （Bacillariophyceae）, two strains of Tetraselmis sp. （Chlorodendrophyceae） and one strain ofAmphikrikos sp. （Trebouxiophyceae） were purified successfully. The method shows promise for batch- purifying microalgal cultures.
