Antibacterial activity of a disaccharide isolated fromStreptomycessp. strain JJ45 againstXanthomonassp.

Abstract

Of the 316 actinomycetes strains isolated from various habitats, Streptomyces sp. strain JJ45 showed the strongest antibiotic activity against the plant pathogenic bacteria Xanthomonas campestris pv. campestris and was thus chosen for further study. The 16S rRNA gene sequence (1500 bp) and rpoB gene partial sequence (306 bp) of Streptomyces strains JJ45A and JJ45B were determined. The respective strain JJ45B sequences exhibited 96.8% identity with the Streptococcus gelaticus 16S rRNA gene sequence and 98.4% identity with the Streptococcus vinaceus ATCC 27478 rpoB partial sequence. The fermentation broth of the JJ45B strain was extracted to find an inhibitor of bacterial growth. The distilled water extract showed the highest activity against pathogenic bacteria. The active molecule was isolated by column chromatography on polyacrylamide or silica gel, thin-layer chromatography, and HPLC. It showed growth inhibition activity only toward phytopathogenic Xanthomonas sp. The structure of the compound was identified as alpha-l-sorbofuranose (3-->2)-beta-D-altrofuranose based on the interpretation of the nuclear magnetic resonance spectra.

Antibacterial Activity ofPseudonocardiasp. JB05, a Rare Salty Soil Actinomycete againstStaphylococcus aureus

“…Our results showed that the dH 2 O extract was the most active extract against S. aureus , compared to those extracted using organic solvents. As an appropriate polar solvent, dH 2 O was used to extract the compound before being compared with the one from the organic solvent [18]. The dH 2 O extract was fractionated according to the following procedure: a total of 15 fractions were separated through a silica gel column (Figure 3(a)).…”

“…The cell free supernatant was concentrated (20X) using a vacuum centrifugation (Speed Vac AES 1010, Savant). The concentrated supernatant was dissolved with 1 mL of distilled water (dH 2 O), gently vortexed, and extracted sequentially with dH 2 O, n-hexane and/or ethyl acetate [18]. …”

“…The active fractions were pooled and loaded onto G25 column chromatography and analyzed by thin layer chromatography (TLC) on silica gel plates (SiO 2 , Merck) with acetonitrile (ACN): methanol (MeOH): dH 2 O (6 : 1 : 3, v/v/v) [18]. The anthrone reagent (0.1 g anthrone, 50 mL pure H 2 SO 4 , and 5 mL dH 2 O) was sprayed onto the silica plate to detect the soluble sugars.…”

Characterization and Antibacterial Activity of a Glycoside Antibiotic from <i>Streptomyces variabilis</i> PO-178

“…The molecule was effective against Xanthomonas sp. (Kang et al, 2009). In another study, Gautham (2012) isolated an antibiotic active against bacteria and molds from butanol extract of Streptomyces fradiae GOS01.…”