The yeast composition and antibacterial activities in sea cucumber Apostichopus japonicus
LI Ming1,MA Yue-xin1,LIU Zhi-ming1,YANG Zhi-ping2,BAO Peng-yun1,SONG Jian1
1.Key Laboratory of Mariculture&Stock Enhancement in North China's Sea,Ministry of Agriculture,Dalian Ocean University,Dalian 116023, China;2.Dalian Huixin Titanium Equipment Dev.Co.,Ltd.,Dalian 116023,China
Abstract: In this study,23 yeast strains were isolated from body surface,intestine and respiratory tree of sea cucumberApostichopus japonicususing PDA,YPD,and MEA media.The genomic DNA was extracted from the yeasts by bead beating method and PCR amplification of the yeast 26S rDNA fragments was performed using primer pairs NL-1/NL-4.PCR products of 26S rDNA were sequenced and the most similar sequences were obtained by Blast in GenBank database.All the sequences were analyzed by the package Mega 4.0 statistics and cluster analysis. The phylogenetic tree generated by the Neighbor-joining method showed that the yeasts isolated from the sea cucumber collected at Bailanzi area in cost were identified asRhodotorulaspp.,Metschnikowiasp.,andTrichosporonspp.,and the yeasts in the sea cucumber collected in sea waters of Heishijiao were divided intoRhodotorulaspp.,Candidaspp.,Debaryomycesspp.,Hanseniasporasp.andPichiasp.Antagonistic activity tests performed by the indicators of eight strains pathogenic bacteria found in the sea cucumber using overlay technique revealed that about 73.9%of the isolated yeast strains showed antibacterial activity.The yeasts derived from body surface,intestine and respiratory tree of the sea cucumber had different bioactivity and various antibacterial spectra and strengths. The antibacterial activity of strain C11 was found to be the maximum,and the extracellular products of strains C11, C14 and C21 precipitated with ammonium sulfate also had antibacterial activity.Crude extract obtained by precipitation of the supernatant of C14 with 65%ammonium sulfate was sensitive to heat and proteinase K,indicating its antagonistic substance was protein.
李明, 马悦欣, 刘志明, 杨志平, 包鹏云, 宋坚. 刺参机体酵母菌组成及其拮抗活性的研究[J]. 大连海洋大学学报, 2012, 27(5): 436-440.
LI Ming, MA Yue-xin, LIU Zhi-ming, YANG Zhi-ping, BAO Peng-yun, SONG Jian. The yeast composition and antibacterial activities in sea cucumber Apostichopus japonicus. Journal of Dalian Ocean University, 2012, 27(5): 436-440.
2012, Vol. 27 
