Isolation and Characterization of Bacteriocinogenic Enterococcal and Lactococcal Strains from South of Morocco Dairy Product

Abstract

Aim:To investigate the occurrence of bacteriocinogenic lactic acid bacteria (BAL) in different animal's milk of the south of Morocco. Place and Duration Methodology: A total of 2000 different colonies, isolated from 42 samples of dromedary, ewe's, goat and cow spontaneously fermented milk collected from some southern regions of Morocco, were tested for antimicrobial activity. Three indicator strains were used; Listeria innocua, Bacillus subtilis and Enterococcus hirae. The selected strains are phenotypically and biochemically Elmoslih et al.; BJI, 18(4): 1-16, 2017; Article no.BJI.32919 2 identified, especially by API 20 Strep galleries. In addition, the sanitary and technological aspects of these strains are studied. Results: Among the active strains 150 strains were selected, and 91% among them were identified as lactic acid bacteria. Out of these, 11 strains isolated from dromedary and ewe's milk are shown to be active by the agar well diffusion assay (AWDA). Seven (7) strains were identified as Enterococcus faecium, three (3) as Enterococcus faecalis and only one (1) strain was identified as Lactococcus lactis. The twelve strains are active against a wide range of pathogenic and spoilage bacteria, including Listeria monocytogenes, Staphylococcus aureus and Escherichia coli. In addition, all of these strains shown to lack haemolytic, decarboxylatic, proteolytic and lipolytic activities and to be susceptible to most tested antibiotics. Conclusion: These results suggest a potential application of isolated strains of lactic acid bacteria in bio-preservation of fermented foods especially dairy products. Original Research Article

Enterococci: Between Emerging Pathogens and Potential Probiotics

“…Enterococci occur in different foods; dairy products (cheeses, raw milk) [23–26], fermented vegetables (olives, fermented sorghum) [27–33], meats, fish, and sea foods [34–38].…”

Genetic diversity of lactic acid bacteria isolated from Sumbawa horse milk, Indonesia

“…Enterococcus strains group have been isolated from raw milk are E. faecalis and E. casseliflavus (Gelsomino et al 2002), E. lactis (Bauer et al 2009), E. italicus, and E. faecium (Gaaloul et al 2014). E. occurs in different foods of dairy products, for instance, cheeses and raw milk (Morandi et al 2012;Elmoslih et al 2017). Enterococcus is found in a variety of artisanal cheeses made from raw or pasteurized milk from goats, sheep, buffaloes, and cows (Cogan et al 1997;Franz et al 1999).…”

Investigating the effect of commercial starter cultures on the physicochemical and microbiological properties of Merguez, an artisanal Moroccan sausage

“…As per current knowledge, lactic acid bacteria (LAB), such as Lactobacillus curvatus, L. sakei, Lactobacillus plantarum and P. acidilactici (Leroy et al, 2006;Dominguez et al, 2016) and certain non-pathogenic staphylococcal species, primarily S. carnosus, S. xylosus and Staphylococcus saprophyticus (Morot-Bizot et al, 2007), are the most frequently identified species used as commercial starter cultures in sausages. LAB present in fermented meat plays an essential role in lowering the pH through carbohydrate fermentation and has antimicrobial properties against a broad spectrum of microorganisms (Achemchem et al, 2012;Elmoslih et al, 2017;Hu et al, 2021). In contrast, staphylococci are accountable for the stability of the red color via the nitrate reductase reaction, suggesting that staphylococcal species may have some favorable impacts on sensory properties.…”