百香果果浆内生细菌的分离鉴定及生长条件的研究

Isolation, identification and growth condition of endophytic bacteria in passion fruit pulp

为了解百香果果浆的内生细菌,该研究采用平板计数琼脂(PCA)培养基从百香果果浆中分离内生细菌,通过形态观察及分子生物学技术对其进行鉴定,并对其生长条件进行研究。结果表明,从百香果果浆中分离得到3株菌落形态单一、均呈浅黄色的内生细菌,分别编号为GJ2-5、GJ2-13、GJ2-19,均呈革兰氏阳性。3株内生细菌均为泛菌属(Pantoea),其中,菌株GJ2-5和GJ2-13均为分散泛菌(Pantoea dispersa),菌株GJ2-19为Pantoea eucrina。3株内生细菌的最适生长培养基均为LB液体培养基,最适生长pH值均为5.5,最适生长温度均为35℃,生长周期为迟滞期(0~6 h)、对数期(6~18 h)、平稳期(18~22 h)和衰亡期(22 h以后)。

To study the endophytic bacteria in passion fruit pulp,the endophytic bacteria were isolated from the passion fruit pulp by plate count agar(PCA)medium,and identified by morphological observation and molecular biological technique.At the same time,the growth conditions of the target strains were studied.The results showed that three endophytic bacteria with single colony morphology and pale yellow color were isolated from the passion fruit pulp,and numbered GJ2-5,GJ2-13,GJ2-19,which were Gram-positive bacteria.The three endophytic bacteria were Pantoea,among them,the strains GJ2-5 and GJ2-13 were Pantoea dispersa,and the strain GJ2-19 was Pantoea eucrina.The optimal growth medium for the three endophytic bacteria was LB liquid medium,the optimal growth pH was 5.5,and the optimal growth temperature was 35℃.The growth cycle was lag phase(0-6 h),logarithmic phase(6-18 h),stationary phase(18-22 h)and decline phase(after 22 h).