Open AccessNew dithiolopyrrolone antibiotics induced by adding sorbic acid to the culture medium of Saccharothrix algeriensis NRRL B‐24137
Author(s) -
Merrouche Rabiâa,
Bouras Noureddine,
Coppel Yannick,
Mathieu Florence,
Sabaou Nasserdine,
Lebrihi Ahmed
Publication year - 2011
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2011.02246.x
Subject(s) - antibiotics , fermentation , chemistry , antimicrobial , sorbic acid , minimum inhibitory concentration , microbiology and biotechnology , food science , biochemistry , biology , organic chemistry
Dithiolopyrrolone antibiotics, produced by several microorganisms, are known for their strong antimicrobial activities. This class of antibiotics generated new interest after the discovery of their anticancer and antitumor properties. In this study, four new antibiotics were purified from the fermentation broth of Saccharothrix algeriensis NRRL B‐24137 and characterized as dithiolopyrrolone derivatives. These new dithiolopyrrolone antibiotics were induced by adding sorbic acid, as precursor, at a concentration of 5 mM to the semi‐synthetic medium. The analysis of the induced antibiotics was carried out by HPLC. The maximal production of the antibiotics PR2, PR8, PR9 and PR10 was 0.08±0.04, 0.21±0.04, 0.13±0.03 and 0.09±0.00 mg L −1 , respectively, obtained after 8 days of fermentation. The chemical structures of these antibiotics were determined by 1 H‐ and 13 C‐nuclear magnetic resonance, mass and UV‐visible data. The four new dithiolopyrrolone antibiotics – PR2, PR8, PR9 and PR10 – were characterized, respectively, as crotonyl‐pyrrothine, sorbyl‐pyrrothine, 2‐hexonyl‐pyrrothine and 2‐methyl‐3‐pentenyl‐pyrrothine. The minimum inhibitory concentrations of the new induced antibiotics were determined.