Biological Activity and Composition of Metabolites of Potential Agricultural Application from <i>Streptomyces carpaticus</i> K-11 RCAM04697 (SCPM-O-B-9993)

Abstract

Abstract—Strain K-11 was isolated from the highly saline brown semi-desert soil of the Astrakhan region. Based on analysis of the 16S rRNA gene sequence, this strain was identified as Streptomyces carpaticus K-11 RCAM04697 (SCPM-O-B-9993). Whole genome sequencing of the strain was performed. Phytotoxicity, antiviral, antioxidant, antifungal, and insecticidal activities of the strain were studied. All extracts and suspensions of S. carpaticus strain RCAM04697 had plant-stimulating activity. Antiviral properties was exhibited as suppression of development and propagation of viral pathogens in laboratory conditions: Tomato Mosaic Virus (ToMV) – 26.3%, Cucumber Mosaic Virus (CMV) – 33.8%, Y-Potato Virus (YVK) (Potato Y potyvirus, PVY) – 51.3%, Potato X-Virus (PVX) (Potato X potyvirus, PVX) – 41.3%. The highest antioxidant activity was shown by a suspension of S. carpaticus strain RCAM04697 (88.8%) and its aqueous-alcoholic (20 : 80) extract (76.0%). The strain inhibited growth of the phytopathogenic fungus Fusarium sporotrichioides to varying degrees. The insecticidal activity against Aphis fabae after 6 h of treatment was 100% in the variants with suspension treatment, water-alcohol (80 : 20, 50 : 50), methanol, and hexane extracts. The metabolites of the S. carpaticus RCAM04697 strain included flavonoids, alkaloids, glycosides, organic acids (isocitric, acetic, fumaric, lactic, pyruvic, and malic), alcohols, aldehydes, hydrocarbons, ethers, sulfur-containing compounds, and other groups of low-molecular weight organic compounds.