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Plant roots are associated with diverse communities of endophytic bacteria which do not exert adverse effects. The diversity of bacterial endophytes associated with ginseng roots cultivated in three different areas in Korea was investigated. Sixty-three colonies were isolated from the interior of ginseng roots. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolates belonged to three major phylogenetic groups: the high G+C Gram-positive bacteria (HGCGPB), low G+C Gram-positive bacteria (LGCGPB), and the Proteobacteria. The dominant species at the three different ginseng growing areas were: HGCGPB at Ganghwa (55.0%), LGCGPB at Geumsan (45.5%), and Proteobacteria at Jinan (61.9%). Most cellulase-, xylanase-, and pectinase-producing colonies among the isolates belong to the LGCGPB group, except for Pectobacterium carotovora which belonged to the Proteobacteria. The 13 isolates belonging to LGCGPB and Proteobacteria were assessed for their antifungal activity against phytopathogenic fungi such as Rhizoctonia solani. Among them, Paenibacillus polymyxa GS01, Bacillus sp. GS07, and Pseudomonas poae JA01 show potential activity as biocontrol agents against phytopathogenic fungi. Finally, most of the low G+C Gram-positive bacteria with antifungal activity against phytopathogenic microorganisms showed cellulolytic enzyme activity while some Proteobacteria with the antifungal activity and the high G+C Gram-positive bacteria did not show any cellulolytic activity.

We examined the role of microorganisms in the degradation of the organophosphorus (OP) insecticide chlorpyrifos (CP) during kimchi fermentation. During the fermentation of kimchi, 30 mg L(-1) of CP was added and its stability assayed during fermentation. CP was degraded rapidly until day 3 (83.3%) and degraded completely by day 9. Four CP-degrading lactic acid bacteria (LAB) were isolated from kimchi fermentation in the presence of 200 mg L(-1) CP and were identified as Leuconostoc mesenteroides WCP907, Lactobacillus brevis WCP902, Lactobacillus plantarum WCP931, and Lactobacillus sakei WCP904. CP could be utilized by these four strains as the sole source of carbon and phosphorus. Coumaphos (CM), diazinon (DZ), parathion (PT), and methylparathion (MPT) were also degraded by WCP907, WCP902, WCP931, and WCP904 when provided as sole sources of carbon and phosphorus.

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