龙须菜的无菌处理及其典型附生菌的分离鉴定

Aseptic treatment and isolation and identification of epiphytic bacteria from marine red alga Gracilariopsis lemaneiformis

采用不同浓度的氨苄青霉素、卡那霉素、氯霉素以及放线菌酮单独及组合处理龙须菜,利用16S r RNA基因序列和ITS序列对分离到的细菌和真菌进行分子鉴定,比较获得无菌龙须菜的最佳抗生素处理方法.结果表明:100μg·m L^(-1)氯霉素、100μg·m L^(-1)氨苄青霉素及50μg·m L^(-1)放线菌酮组合使用抑菌效果最好.并从龙须菜的培养液中分离鉴定出4株细菌,分别为鲁杰氏菌属(Ruegeria)、单胞菌属(Alteromonas)、Maribacter属和Fluviimonas属,1株真菌为Urocystales或Fereydounia属,其中鲁杰氏菌为龙须菜附生细菌的优势菌群.

The marine red algae Gracilariopsis lemaneiformis were treated by one or two following antibiotics with different concentrations： ampicillin, kanamycin, chloromycetin and cycloheximide. Different bacteria and fungi were identified by using 16 S r RNA gene and ITS sequences. The main focus of the current study was the optimal antibiotic treatment method to obtain aseptic red alga Gp. lemaneiformis. The results showed that combination of 100 μg·m L^-1 ampicillin, 100 μg·m L^-1 chloromycetin and 50 μg·m L^-1 cycloheximide was suitable for this algal aseptic treatment. Meanwhile, four strains of bacteria and one strain of fungi were isolated from the algal culture medium. The results showed that the four strains of bacteria belonged to genus of Ruegeria, Alteromonas, Fluviimonas, Maribacter, and one fungus was Urocystales or Fereydounia. The bacteria Ruegeria was the dominant bacteria in the epiphytic bacteria of Gp. lemaneiformis. The study provided sterile materials for the molecular biology research of Gp. Lemaneiformis. Furthermore, the results provide theoretical basis for the study of the relationship between bacteria and algae, which might help algal disease treatment in the future.