Selecting And Identification Of Strains Producing Bacteriocins Inhibiting Gram-negative Bacteria And Purification Of Plantaricin LPC818

Just because the variety of bacteriocins from Lactobacillus plantarum andbeneficial effects, it became popular to do research on bacteriocins from L. plantarum.In the present paper, the isolation and identification of the strains producingbacteriocins were reported. Then, the primary characteristics of plantaricin LPC818, anovel bacteriocin with a broad inhibitory spectrum produced by Lactobacillusplantarum LPC818, were analyzed. These results were described as followes:1.4strains producing bacteriocin were screened from a variety of fermentedplant. These strains were identified by phenotypical and physiological tests andanalysis of16S rRNA gene sequence. The results demonstrated that one of thembelonged to Lactobacillus arizonensis and the rest belonged to Lactobacillusplantarum.2. Plantaricin LPC818kept active between pH3to pH5.5; plantaricin LPC818was stable under the high temperature due to the result that the residual activity wasbeyond80%when it was treated100℃for30min; it was completely inactive whentreated by protease E, protease K and lipase, while partial inactive when treated bypapainase and chymotrypsin. The results revealed that plantaricin LPC818would be akind of lipoprotein.3. Plantaricin LPC818has a broad inhibitory spectrum which can inhibit variousGram positive bacteria and Gram negative bacteria. And studying on the mode ofaction aginst Salmonella pullorum, it showed that plantaricin LPC818could kill thecells.4. Plantaricin LPC818was purified by60%saturation (NH4)2SO4, SephadexG25column chromatography and RP-HPLC. The purification fold and the yield ofplantaricin LPC818were7.87and0.8%, respectively; the molecular weight ofplantaricin LPC818was deduced as745.10Da by Tricine-SDS-PAGE and ESI-MS.