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.

Safety Evaluation of Enterocin Producer Enterococcus sp. Strains Isolated from Traditional Turkish Cheeses

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.

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.

Identification of Anti-microbial Producing Enterococci Isolated from Iranian Raw Milk Cheeses Using Polyphasic Approach

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...

Enterococcus faecium F58, a bacteriocinogenic strain naturally occurring in Jben, a soft, farmhouse goat's cheese made in Morocco

Journal of Applied Microbiology, 2005

Characterization of Ent F-58 produced by Enterococcus faecium strain F58 isolated from Jben, a soft, farmhouse goat's cheese manufactured without starter cultures. Methods and Results: E. faecium strain F58 was isolated because of its broad inhibitory spectrum, including activity against food-borne pathogenic and spoilage bacteria. The antimicrobial substance was produced during the growth phase, with maximum production after 16-20 h of incubation at 30°C, and was stable over a wide pH range (4-8) and at high temperatures (5 min at 100°C). The enterocin was purified to homogeneity using cation exchange and hydrophobic interaction on C-18 and reverse-phase high-performance liquid chromatography. The activity was eluted as two individual active fractions (F-58A and F-58B) and matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry analysis showed masses of 5210AE5 and 5234AE3 Da respectively. Both peptides were partially sequenced by Edman degradation, and amino-acid sequencing revealed high similarity with enterocin L50 (I). PCR-amplified fragments containing the structural genes for F-58 A and B were located in a 22-kb plasmid harboured by this strain. We verified that it also holds the structural gene for P-like enterocin. Conclusion: E. faecium strain F58 from Jben cheese, a producer of enterocin L50, exerts an inhibitory effect against strains of genera such as Listeria, Staphylococcus, Clostridium, Brochothrix and Bacillus. Enterocin was characterized according to its functional and biological properties, purification to homogeneity and an analysis of its amino acid and genetic sequences. Significance and Impact of the Study: E. faecium strain F58 is a newly discovered producer of enterocin L50, the biotechnological characteristics of which indicate its potential for application as a protective agent against pathogens and spoilage bacteria in foods.

Partial characterisation of enterocin KP produced by Enterococcus faecalis KP, a cheese isolate

Enterococcus faecalis KP, a bacteriocin-producing strain, was identified using 16S rRNA gene sequence homology (99%). Enterocin KP from E. faecalis KP was sensitive to papain and ß-mercap-toethanol, but resistant to trypsin, pepsin, lipase, catalase, a-amylase, organic solvents, detergents, EDTA and heat treatment (90°C ⁄ 30 min). It was active at a wide pH range (2.0–8.0) and produced at maximum level in de Mann Rogosa Sharpe broth at 32°C with an inoculum amount of 0.1–1.0% and an initial pH of 5.5–7.5. It was active against some Gram-positive bacteria, including Listeria monocytogenes. It showed bactericidal activity against L. monocytogenes and its molecular weight was approximately 5.8 kDa.