AUTHOR=Zhang Shuxiang , Wu Jun , Jiang Zhou , Zhang Le , Song Tao , Liu Xinhua , Yin Caiping , Zhang Yinglao 

TITLE=Pigments of aminophenoxazinones and viridomycins produced by termite-associated Streptomyces tanashiensis BYF-112

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.1110811

DOI=10.3389/fmicb.2022.1110811

ISSN=1664-302X

ABSTRACT=<p>Termite-associated <italic>Streptomyces tanashiensis</italic> BYF-112 was found as a potential source for yellow and green pigments, which were stable under the tested temperature, light and metal ions. Eight metabolites (<bold>1</bold>–<bold>8</bold>), including four new natural yellow pigments aminophenoxazinones (<bold>1</bold>–<bold>4</bold>), and two rarely iron dependent green pigments viridomycin A and F (<bold>9</bold>–<bold>10</bold>) were isolated from BYF-112 cultured in YMS and YMS treated with FeSO<sub>4</sub>, respectively. The metabolites <bold>2</bold>–<bold>4</bold> displayed a significant safety performance on the normal liver cell line L-02, while the metabolite <bold>1</bold> showed weak cytotoxicity against the L-02 and several cancer cells. Especially, in the filter paper disc tests, the compound <bold>1</bold> possessed strong antibacterial activity against methicillin-resistant <italic>Staphylococcus aureus</italic> (MRSA) with the zone of inhibition (ZOI) of 15.3 mm, which was equal to that of referenced levofloxacin (ZOI = 15.2 mm). And the metabolite <bold>1</bold> also showed moderate antibacterial activities against <italic>Micrococcus teragenus</italic> and <italic>S. aureus</italic>, with the ZOI values of 15.3 and 17.2 mm. In addition, by the minimum inhibitory concentration (MIC) assay, the compound 1 displayed potential antibacterial activities against <italic>M. teragenus</italic>, <italic>S. aureus</italic> and MRSA, with the MIC values of 12.5, 12.5, and 25.0 μg/ml, respectively. The present results indicate that BYF-112 may be a promising source for safe and bioactive pigments, which can be used for further development and industrial applications.</p>