A new antibacterial and antioxidant S07-2 compound produced by Bacillus subtilis B38.
An antibacterial compound, S07-2, was purified to homogeneity by hydrophobic interaction, anion exchange, C18 reverse-phase and HS PEG HPLC. The molecular mass of S07-2 was 905.6 Da as determined by MS. The S07-2 compound was resistant to high temperatures (up to 100 degrees C) and could withstand a wide range of pH from 3 to 10. In addition, its antibacterial activity was preserved after treatment with proteases. Biochemical characterization revealed its cyclic peptide structure. This compound showed a bactericidal effect against important food-spoilage bacteria and food-borne pathogens including Listeria monocytogenes and Enterococcus faecalis with lethal concentration values of 62.5 microg mL(-1) and against Salmonella enteritidis at a concentration of 31.25 microg mL(-1). However, no cytotoxic effect against human erythrocytes was recorded. Furthermore, the S07-2 compound displayed a remarkable Fe(2+)-chelating activity (EC(50)=9.76 microg mL(-1)) and 1-diphenyl-2-picrylhydrazyl-scavenging capacity (IC(50)=65 microg mL(-1)). All these chemical and biological features make S07-2 a useful compound in the food industry as a natural preservative.
Tabbene
Olfa
O
Laboratoire des Substances Bioactives, Centre de Biotechnologie de Borj-Cedria, Tunis, Tunisia.
Karkouch
Ines
I
Elkahoui
Salem
S
Cosette
Pascal
P
Mangoni
Maria-Luisa
ML
Jouenne
Thierry
T
Limam
Ferid
F
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology* / Q000633:toxicity; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology* / Q000633:toxicity; D001412:Bacillus subtilis / Q000378:metabolism*; D002614:Chelating Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000633:toxicity; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D004355:Drug Stability; D013293:Enterococcus faecalis / Q000187:drug effects; D004912:Erythrocytes / Q000187:drug effects; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D020128:Inhibitory Concentration 50; D008089:Listeria monocytogenes / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000378:metabolism; D012477:Salmonella enteritidis / Q000187:drug effects
D000900:Anti-Bacterial Agents; D000975:Antioxidants; D002614:Chelating Agents; D010447:Peptide Hydrolases