Sixteen lactic acid bacterial strains were isolated from silage and cow dung samples, and characterized to identify their potential as silage additives. They were identified as the members of the genera Lactobacillus, Enterococcus, and Weissella, and clustered into nine groups based on the sequences of the genes for 16S rRNA, RNA polymerase alpha subunit, 60-kDa heat shock protein, and phenylalanyl-tRNA synthase alpha subunit. Among them, the three strains which were genetically similar to L. plantarum showed the fastest growth and pH decrease in MRS and rye extract media, the highest numbers of available carbohydrates, and the widest ranges of pH, temperature, and salinity for growth. In addition, they showed no amplified DNA products in the PCR examination targeting the genes for the production of biogenic amines, and the MRS media where they had been cultured showed relatively high inhibition effect against the growth of silage-spoiling microorganisms, including fungi, yeast, and clostridia. The results suggest that these strains are good candidates for silage additives. However, the rye extract media where the lactic acid bacteria had been cultured had no effect on or stimulated the growth of the silage-spoiling microorganisms, and the causes must be established for the practical use of the lactic acid bacteria as silage additives.

Triazole fungicides occupy an important portion in the global fungicide market and are relatively persistent in soil compared to the other fungicides, suggesting possible adverse effects of the fungicides on human health and environment. In this study, we tried to isolate microorganisms from orchard soils, which can decompose the triazole fungicides, tebuconazole, fluquinconazole, and difenoconazole. Only difenoconazole was completely degraded in the enrichment culture, from which several difenoconazole-degrading bacteria were isolated. They showed the same rep-PCR pattern thus only one strain, C8-2, was further studied. The strain was identified as Sphingomonas sp. C8-2 based on its 16S rRNA gene sequence and decomposed 100 mg/L of difenoconazole in a minimum medium to an unknown metabolite with a molecular weight of 296 within 24 hours. The inhibition effect of the metabolite against representative soil microorganisms significantly decreased compared to that of difenoconazole thus the bacterial strain is expected to be used for the detoxification of difenoconazole in soil and crop.

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