Naslov
Coculture-inducible bacteriocin biosynthesis of different probiotic strains by dairy starter culture Lactococcus lactis

Autori
Kos, Blaženka ; Beganović, Jasna ; Jurašić, Lina ; Švađumović, Martina ; Leboš Pavunc, Andreja ; Habjanič, Ksenija ; Šušković, Jagoda

Izvornik
Mljekarstvo (0026-704X) 61 (2011), 4; 273-282

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
antimicrobial activity ; bacteriocins ; induction of bacteriocin biosynthesis ; probiotics

Sažetak
Bacteriocin biosynthesis by probiotic strains can contribute to the colonisation resistance of the host, its protection against gastrointestinal pathogens and facilitate the establishment of a probiotic strain in the competitive environment of the gut, while those produced bacteriocins have received considerable attention due to their potential application as biopreservatives, especially in dairy industry. Hence, the objective of this research was to investigate an antimicrobial activity of probiotic strains Lactobacillus helveticus M92, Lactobacillus plantarum L4, Enterococcus faecium L3 with the special focus on their bacteriocinogenic activity. Their antimicrobial activity was tested towards representatives of the same or related bacterial species for bacteriocinogenic activity, and towards different test microorganisms, potential food contaminants or causative agents of gut infections. Presence and close contact of competitive microorganism has been reported to be an environmental factor affecting bacteriocin biosynthesis by lactic acid bacteria. Hence, in order to induce bacteriocin production, probiotic cells were cocultivated with Lactococcus lactis subsp. lactis LMG 9450, one of the most important starter cultures in cheese production. The detection of bacteriocin coding genes was investigated by PCR amplification with sequence-specific primers for helveticin and confirmed for probiotic strain Lactobacillus helveticus M92. All examined probiotic strains have shown bacteriocinogenic activity against food spoilage and pathogenic bacteria which is an important functional treat of probiotic strains important in competitive exclusion mechanism which provides probiotic strains selective advantage against undiserable microorganisms in gastrointestinal tract of the host. According to obtained results, living cells of starter culture Lact. lactis subsp. lactis LMG 9450 induce bacteriocin production by examined probiotic strains but starter culture itself was not sensitive to bacteriocin activity.

Izvorni jezik
Engleski

Znanstvena područja
Biotehnologija

POVEZANOST RADA