Bioactive Enterococci Isolated from Slovak Ewes’ Lump Cheese (original) (raw)
Antimicrobial Activity Potential of Enterococcus spp. Isolated from Some Traditional Turkish Cheeses
Kafkas Universitesi Veteriner Fakultesi Dergisi, 2016
Enterococci can produce enterocins which have antimicrobial activity against Gram-positive and also Gram-negative pathogenic, toxigenic and food-spoilage bacteria. The aim of this study was to determine the antimicrobial activity of Enterococcus spp. isolated from traditional Turkish cheeses such as Kashar, Manyas, Sepet, Kelle, Mihalic, Tulum. The isolates were tested against Listeria monocytogenes, Listeria innocua, Listeria ivanovii, Staphylococcus aureus and Enterococcus faecalis and also detected the presence of entA and entB genes of these isolates. Total 66 of enterococcal isolates were obtained from 34 of cheese samples and 25 of these isolates showed antimicrobial activity against tested reference bacteria by using agar spotting method. Also it was determined most of Enterococcus spp. carried enterocin encoding entA and entB genes. We concluded that these isolates or their enterocins may have a potential for food preservation, however they should be evaluated in terms of food safety.
Polish Journal of Microbiology, 2017
The purpose of this study was to determine the antimicrobial activity and occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate some of their virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. Structural genes entA, entB, entP and entX were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated anyβ-haemolytic activity and only one strain had gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was detected only in this strain. K e y w o r d s: Enterococcus sp. from cheeses, antibiotic resistance of food borne enterococci bacteriocin production ability, virulence factors
Polish Journal of Microbiology
The purpose of this study was to determine the antimicrobial activity and the occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate of their some virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. entA, entB, entP and entX structural genes were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated β-haemolytic activity and only one strain has gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was only detected in this strain.
Antimicrobial Resistance of Enterococcus sp. Isolated from Sheep and Goat Cheeses
Foods
This study aimed to calculate the proportion of antibiotic resistance profiles of Enterococcus faecium, E. faecalis, and E. durans isolated from traditional sheep and goat cheeses obtained from a selected border area of Slovakia with Hungary (region Slanské vrchy). A total of 110 Enterococcus sp. were isolated from cheese samples, of which 52 strains (E. faecium (12), E. faecalis (28), E. durans (12)) were represented. After isolation and identification by polymerase chain reaction and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry, the enterococci (E. faecium, E. faecalis, and E. durans) were submitted to susceptibility tests against nine antimicrobial agents. In general, strains of E. faecalis were more resistant than E. durans and E. faecium. A high percentage of resistance was noted in E. faecalis to rifampicin (100%), vancomycin (85.7%), teicoplanin (71.4%), erythromycin (71.4%), minocycline (57.1%), nitrofurantoin (57.1%), ciprofloxacin (14.3%), a...
Slovak Local Ewe’s Milk Lump Cheese, a Source of Beneficial Enterococcus durans Strain
Foods
Slovak ewe’s milk lump cheese is produced from unpasteurized ewe’s milk without any added culture. Because of the traditional processing and shaping by hand into a lump, this cheese was given the traditional specialty guaranteed (TSG) label. Up till now, there have existed only limited detailed studies of individual microbiota and their benefits in ewe’s milk lump cheese. Therefore, this study has been focused on the beneficial properties and safety of Enterococcus durans strains with the aim to contribute to basic dairy microbiology but also for further application potential and strategy. The total enterococcal count in cheeses reached 3.93 CFU/g (log 10) ± 1.98 on average. Based on a MALDI-TOF mass spectrometry evaluation, the strains were allotted to the species E. durans (score, 1.781–2.245). The strains were gelatinase and hemolysis-negative (γ-hemolysis) and were mostly susceptible to commercial antibiotics. Among the strains, E. durans ED26E/7 produced the highest value of la...
Antilisterial Activity by Enterococcus Species Isolated from Traditional Cheeses
2020
In this study, it was aimed to detect the antimicrobial activity of 312 Enterococcus species against Listeria monocytogenes. Antimicrobial activity was detected by agar spot and well diffusion assay. A total of 201 enterococcal strains inhibited the growth of L. monocytogenes strains based on the agar spot test. Only 44 strains showed antimicrobial activity against L. monocytogenes strains using agar well diffusion assay. Of the 44 enterococcal strains screened, 6 E. faecium (2.99%) strains had a high antimicrobial effect against indicator L. monocytogenes strains. The antilisterial activity of 6 E. faecium strains had lost after treatment of proteinase K, trypsin and pepsin. The antimicrobial compounds of these strains could be a protein or peptides nature. E. faecium strains were more active against L. monocytogenes than E. faecalis strains.
Current Trends of Enterococci in Dairy Products: A Comprehensive Review of Their Multiple Roles
Foods, 2021
As a genus that has evolved for resistance against adverse environmental factors and that readily exchanges genetic elements, enterococci are well adapted to the cheese environment and may reach high numbers in artisanal cheeses. Their metabolites impact cheese flavor, texture, and rheological properties, thus contributing to the development of its typical sensorial properties. Due to their antimicrobial activity, enterococci modulate the cheese microbiota, stimulate autolysis of other lactic acid bacteria (LAB), control pathogens and deterioration microorganisms, and may offer beneficial effects to the health of their hosts. They could in principle be employed as adjunct/protective/probiotic cultures; however, due to their propensity to acquire genetic determinants of virulence and antibiotic resistance, together with the opportunistic character of some of its members, this genus does not possess Qualified Presumption of Safety (QPS) status. It is, however, noteworthy that some put...
Antibacterial potential of Enterococcus faecium strains isolated from ewes’ milk and cheese
LWT - Food Science and Technology, 2012
The study was conducted to evaluate the antibacterial activity of three bacteriocin-producing Enterococcus faecium strains (TW15, TW20 and TW22) isolated from ewes' milk and cheese sampled in the Patagonian region of Argentina. The strains were tested against spoilage and pathogens microorganisms showing antimicrobial activity towards 4 strains of Listeria monocytogenes, one strain of Listeria innocua and 2 strains of Staphylococcus aureus. E. faecium TW15, E. faecium TW20 and E. faecium TW22 were sensitive to vancomycin. Furthermore, investigation of virulence factors revealed the absence of the genes encoding them. The bacteriocin-like substances (BLISs) produced by the 3 strains were thermostable, pH resistant and can be expressed even in the presence of NaCl (3.0 g/100 g). Moreover, they prove to have a bactericidal mode of action. Results from physicochemical and biochemical characteristics of BLIS produced by these E. faecium strains make them potential candidates to aid in preservation of foods.
Article Info The search for new antimicrobial agents is a field of utmost importance since the prevalence of antimicrobial resistance among key microbial pathogens is increasing at an alarming rate worldwide. This study was performed in order to isolate and identify the potential Enterococci strains exhibiting anti-microbial activity with the help of two anti-microbial detection methods namely Agar-Spot and Well-Diffusion Assay. A collection of Enterococci spp. (about 96 isolates) were isolated from two Iranian raw milk cheeses, namely Lighvan and Koozeh, and subsequently, identified as Enterococcus faecium, Enterococcus faecalis, Enterococcus durans, Enterococcus casseliflavus and Enterococcus italicus by 16S rDNA sequencing. All of the 96 isolates were subjected to Agar-Spot and Well-Diffusion Assay in order to detect their ability to produce antimicrobial compounds. According to Agar-Spot method, 48 out of the 96 isolates produced clear zone on the plates against indicator organi...