The taxonomic positions of actinomycetes isolated from clinical specimens in Japan and Thailand were examined using a polyphasic approach. The strains IFM 0391^T and IFM 10145^T were found to have morphological, biochemical and chemotaxonomic properties consistent with their classification in the genus Nocardia. DNA-DNA hybridization, coupled with sequence analysis of 16S rDNA, indicated that these strains belong to two new species of the genus Nocardia: Nocardia vermiculata for IFM 0391^T (=NBRC 1000427^T = JCM 12345^T = DSM 44807^T), and Nocardia thailandica for IFM 10145^T (=NBRC 100428^T = JCM 12356^T = DSM 44808^T).

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Currently used chemical treatment of the keratinous material is the preferred method of poultry waste disposal in Australia, however it is costly, and environmental pollution problems from the chemical leachates as well as the poor nutritional quality of the end-product render this method undesirable. As the microbial community of the composting cycles have been reported to reduce the odours and pathogens of the domestic animal waste, local industries look for improved technologies of biological origin to treat poultry manure, carcasses and feather.
This study reports on an alternative method utilizing the degradative abilities of the actinomycetes in a composting system developed specifically to break down recalcitrant material and to produce a cleaner and pathogen-free endproduct with particular reference to waste usage and disposal on the Sunshine Coast Region in Queensland, Australia. Keratinolytic actinomycetes from a local poultry farm environment were isolated and used to augment the compost microflora. The inclusion of the organisms into poultry waste compost was successful in producing an odourless, pathogen free product with complete biological degradation of the feather waste in 17 days. The application of this system may improve the rapid disposal of poultry waste aswell as the public and environmental health in the Region.

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Tissue-cultured seedlings of mountain laurel (Kalmia latifolia L.) were treated with strain AOK-30 of Streptomyces padanus in flasks. This treatment accelerated pigmentation of the seedlings. The untreated green seedlings wilted in room conditions within 1 hr of removal from the flasks while the treated reddish seedlings were still turgid. Fresh weight of leaf pieces decreased more quickly in the untreated than in the treated specimens, suggesting that the AOK-30 treatment somehow rendered the seedlings drought-tolerant. Protoplasts were released from untreated green seedlings with cellulase and macerozyme, while xylanase was required in addition to cellulase for protoplast preparation from the treated reddish seedlings, suggesting that composition and structure of the cell walls of seedlings may have been modified by the AOK-30 treatment. Osmotic pressure was higher in protoplasts from the treated than the untreated seedlings. Elevation of osmotic pressure in cells and cell wall modification may partially account for the enhanced drought-tolerance of the AOK-30-treated seedlings.

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An endophytic actinomycete, Streptomyces padanus AOK-30, isolated from a potted mountain laurel (Kalmia latifolia L.) plant, was used to protect tissue-cultured seedlings of mountain laurel from Pestalotia disease and Rhizoctonia root rot. AOK-30, which has a broad antagonistic spectrum against various microbes, did not adversely affect the seedlings in glass flasks. A spore suspension of AOK-30 was spread on the surface of the rooting medium in glass flasks in which seedlings were growing. Ten days later, the 4th upper leaves were inoculated with Pestalotiopsis sydowiana and incubated for 20 days. In controls untreated with AOK-30, substrate mycelia of this fungus grew on all leaves and stems above and below the 4th leaves within 7–10 days after inoculation. Such growth resulted in the wilting death of 13 of 20 seedlings by the 20th day. In contrast, only the inoculated leaves and some neighboring leaves turned brown in 17 of 20 seedlings growing on medium treated with AOK-30. Thus, treatment of the medium surface with AOK-30 efficiently protects the seedlings from infection by P. sydowiana. The treatment of seedlings with AOK-30 in flasks before transplanting in soil and transplanting of untreated seedlings in soil mixed with suspension of AOK-30 significantly and marginally, respectively, slowed the expansion of root rot caused by Rhizoctonia sp. in seedlings in the cell trays.

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