The use of Lactobacillus plantarum L4 for the production of probiotic drink with cabbage juice

U ovom radu je istražena mogućnost primjene probiotičkog soja Lactobacillus plantarum L4 u fermentaciji soka varaždinskog i vranskog kupusa. Tijekom fermentacije, primjenjeni probiotički soj Lactobacillus plantarum L4 je proizveo cca 10 g/L mliječne kiseline, pH vrijednost je iznosila 4,3, a broj živih stanica je iznosio više od 106 CFU/ml. Visok broj stanica probiotičkog soja L. plantarum L4 potvrđenog RAPD metodom, se održao i tijekom 2 tjedna čuvanja fermentiranih sokova kupusa pri temperaturi od 4°C što svrstava proizvedene fermentirane sokove kupusa u probiotičke proizvode jer sadrže više od 106 CFU/ml. Paralelno je provedena spontana fermentacija bez postignuća zadovoljavajućih rezultata što ukazuje na nedovoljnu koncentraciju autohtono prisutnih bakterija mliječne kiseline koje bi mogle započeti fermentaciju. Stoga je provedena izolacija autohtono prisutne populacije bakterija mliječne kiseline. Osam izolata je, na temelju sadržaja ukupnih staničnih proteina, pomoću SDS-PAGE elektroforeze, identificirano kao monokultura vrste Lactobacillus plantarum. Zatim je s izoliranom i umnoženom monokulturom vrste Lactobacillus plantarum provedena fermentacija soka varaždinskog i vranskog kupusa, a dobiveni rezultati usporedivi su s parametrima uspješnosti fermentacije provedene s probiotičkim sojem Lactobacillus plantarum L4. Izolirana monokultura vrste Lactobacillus plantarum i primjenjeni probiotički soj Lactobacillus plantarum L4 su iskazali antibakterijsko djelovanje prema 6 različitih test-mikroorganizama. Visok stupanj preživljavanja i antibakterijsko djelovanje primjenjenih sojeva daje im mogućnost primjene kao starter kultura za fermentaciju supstrata kao što je sok kupusa.The potential for using probiotic strain Lactobacillus plantarum L4 in cabbage juice fermentation was investigated. During the controlled fermentation of cabbage juice “Varaždinski” and “Vranski” cultivar with Lactobacillus plantarum L4, probiotic strain has produced cca 10 g/L lactic acid, pH was 4.3, and number of live cells stayed high (more than 10 CFU/ml). Number of probiotic bacterium Lactobacillus plantarum L4 maintained high during 2 weeks of the fermented cabbage juices storage at 4°C which ranks produced fermented cabbage juices into probiotic products because they contain more than 106 CFU/ml. Spontaneous fermentation was carried out together with controlled fermentation but without satisfying results what points out to deficient concentration of autochthonous lactic acid bacteria that could start the fermentation. Because of that the isolation of autochthonous lactic acid bacteria was carried out. Phenotypic characterization of 8 selected bacterial strains was done by SDS-PAGE of whole cell proteins. Electrophoretic pattern revealed one bacterial strain and it was identified as monoculture species of Lactobacillus plantarum. Furthermore the fermentation of the cabbage juice “Varaždinski” and “Vranski” cultivar was carried out with isolated and cultivated monoculture species of Lactobacillus plantarum and obtained results were comparable with the parametars of fermentation carried out with probiotic strain Lactobacillus plantarum L4. Isolated monoculture species of Lactobacillus plantarum and probiotic strain Lactobacillus plantarum have shown antibacterial activity against six test microorganisms. High degree of survival and antibacterial activity of examined strains offers the possibility of their use as starter cultures for fermentation of the substrate such as cabbage juice