ISOLATION AND PHYLOGENETIC ANALYSIS 495 step at 72 C for 2 min. PCR products were analyzed by electrophoresis in 1% agarose gels and stained with ethidium bromide. The PCR amplification products were sequenced using an ABI3730 DNA Sequencer (USA) with 27f primer. The sequences were compared to those in the GenBank database using the BLAST software package to identify the sequences' similarity. Alignment of 16S rDNA sequences was performed using CLUSTALX software package; the phylogenetic tree was generated using the neighbor-joining algorithms in the Mega III software package. The level of support for the phylogenies derived from neighborjoining analysis was gauged by 100 bootstrap replicates.

A total of 399 bacterial cultures were isolated. Among these, 13 isolates from S. tenui, 42 from H. rugosa, and 20 from D. avara showed pronounced antimicrobial activities and enzymatic potential. The results for 33 representative bacterial strains are presented in Table 1. Many isolates have a broad spectrum of antimicrobial activity, eg, A75, A72, B81, B15, C123. The isolates A05, A64, and B81 were active against E. coli. Some of the isolates exhibited multiple enzymatic activities, eg, protease, lipase, agarase, and chitinase.