title: New dithiolopyrrolone antibiotics induced by adding sorbic acid to the culture medium of Saccharothrix algeriensis NRRL B-24137.
abstract: 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.
authors.affiliation: Laboratoire de Recherche sur les Produits Bioactifs et la Valorisation de la Biomasse (LPBVB), Ecole Normale Supérieure de Kouba, Alger, Algeria.
authors.forename: Rabiâa
authors.initials: R
authors.lastname: Merrouche
authors.forename: Noureddine
authors.initials: N
authors.lastname: Bouras
authors.forename: Yannick
authors.initials: Y
authors.lastname: Coppel
authors.forename: Florence
authors.initials: F
authors.lastname: Mathieu
authors.forename: Nasserdine
authors.initials: N
authors.lastname: Sabaou
authors.forename: Ahmed
authors.initials: A
authors.lastname: Lebrihi
mesh_terms: D000192:Actinomycetales / Q000737:chemistry / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D003470:Culture Media / Q000378:metabolism*; D005285:Fermentation; D007218:Industrial Microbiology; D015394:Molecular Structure; D011760:Pyrrolidinones / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D013011:Sorbic Acid / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D011760:Pyrrolidinones; D013011:Sorbic Acid