New types of antimicrobial compounds produced by Lactobacillus plantarum.
New types of antimicrobial compounds were identified in the culture filtrate of Lactobacillus plantarum VTT E-78076. Activity was detected in the low molecular mass fraction separated by gel chromatography. This fraction totally inhibited the growth of the Gram-negative test organism, Pantoea agglomerans (Enterobacter agglomerans) VTT E-90396. Characteristic compounds from this fraction were identified by GC/MS-analysis and the identification was confirmed using pure commercial reference compounds in identical chromatographs and in antimicrobial tests. The active fraction included benzoic acid (CAS 65-85-0), 5-methyl-2,4-imidazolidinedione (CAS 616-03-5, methylhydantoin), tetrahydro-4-hydroxy-4-methyl-2H- pyran-2-one (CAS 674-26-0, mevalonolactone) and 3-(2-methylpropyl)-2,5-piperazinedione (CAS 5845-67-0, cyclo(glycyl-L-leucyl)). These compounds in concentrations of 10 ppm inhibited growth of the test organism by 10-15% when acting separately, but 100% when all were applied together with 1% lactic acid. The inhibition was 40% by 1% lactic acid alone. The compounds were also active against Fusarium avenaceum (Gibberella avenacea) VTT-D-80147. The inhibition was 10-15% by separate compounds in concentrations of 10 ppm and maximally 20% in combinations. Fungal growth was not inhibited by lactic acid. Inhibition by unfractionated Lact. plantarum culture filtrate was 37% and by the low molecular mass fraction, 27%.
Niku-Paavola
M L
ML
VTT Biotechnology and Food Research, Espoo, Finland. marja-leena.niku-paavola@vtt.fi
Laitila
A
A
Mattila-Sandholm
T
T
Haikara
A
A
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D019817:Benzoic Acid / Q000378:metabolism / Q000494:pharmacology; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000254:growth & development; D005670:Fusarium / Q000187:drug effects* / Q000254:growth & development; D006358:Hot Temperature; D006827:Hydantoins / Q000378:metabolism / Q000494:pharmacology; D019344:Lactic Acid / Q000494:pharmacology; D007778:Lactobacillus / Q000378:metabolism*; D008798:Mevalonic Acid / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D009479:Neuropeptides / Q000378:metabolism / Q000494:pharmacology; D010456:Peptides, Cyclic / Q000378:metabolism / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D006827:Hydantoins; D009479:Neuropeptides; D010456:Peptides, Cyclic; D019344:Lactic Acid; C021166:cyclo(leucylglycine); C047589:5-methylhydantoin; C015367:mevalonolactone; D019817:Benzoic Acid; D008798:Mevalonic Acid