Enterococcus Strains Research Articles

Bacteriocin production and technological properties of Enterococcus mundtii and Enterococcus faecium strains isolated from sheep and goat colostrum.

Enterococci are lactic acid bacteria (LAB) that play a role in the aroma formation, maturation, and sensory development of fermented foods such as meat and dairy products. They also contribute to the improvement of the extended shelf life of fermented foods by producing bacteriocin. The aim of this study was to isolate bacteriocin-producing LAB from sheep and goat colostrum, to characterize the bacteriocin-producing strains, and determine the technological properties of the strains. A total of 13 bacteriocin-producing LAB was isolated and identified as 11 Enterococcus mundtii and two Enterococcus faecium. The strains were found to be genetically different from each other by phylogenetic analysis of 16S rRNA gene sequences and random amplified polymorphic-DNA (RAPD-PCR). It has been determined that bacteriocins show activity in a wide pH range and are resistant to heat, lose their activity with proteolytic enzymes and α-amylase, but are resistant to detergents. While the presence of the munKS gene was detected in all of the strains, it was determined that E. faecium HC121.4, HC161.1, E. mundtii HC147.1, HC166.5, and HC166.8 strains contained multiple enterocin genes. Trisin-SDS-PAGE analysis revealed two active protein bands of approximately 5.1 and 5.5kDa in E. faecium HC121.4 and one active protein band with a weight of approximately 4.96kDa in other strains. E. mundtii strains and E. faecium HC161.1 were identified as mundticin KS producers, and E. faecium HC121.4 was defined as an enterocin A and B producer. Except for E. mundtii HC166.8, acid production of strains was found to be slow at 6h and moderate at 24h. None of them showed extracellular proteolytic and lipolytic activities. It was found that the strains had esterase, esterase lipase, leucine arylamidase, acid phosphatase, and naphthol-AS-Bl-phosphohydrolase activities, while protease activities were low and peptidase activities were high. In conclusion, bacteriocin producer 13 Enterococcus strains isolated from sheep and goat colostrum were found to have the potential to be included in starter culture combinations.

Ureteral Stents Harbor Complex Biofilms With Rich Microbiome-Metabolite Interactions.

We sought to determine microbe-metabolite composition and interactions within indwelling ureteral stent biofilms, determine their association with patient factors including infection, and reconstitute biofilm formation on relevant surface materials in vitro. Upon ureteral stent removal from patients, proximal and distal ends were swabbed. Samples were analyzed by 16S next-generation sequencing and metabolomics. A continuous-flow stir-tank bioreactor was used to reconstitute and quantify in vitro biofilm formation from stent-isolated bacteria on stent-related materials including silicone, polytetrafluoroethylene, polyurethane, polycarbonate, and titanium. Diversity, relative abundance, and association with clinical factors were analyzed with ANOVA and Bonferroni t-tests or PERMANOVA. Biofilm deposition by microbial strain and device material type were analyzed using plate counts and scanning electron microscopy following bioreactor incubation. All 73 samples from 37 ureteral stents harbored microbiota. Specific genera were more abundant in samples from stents wherein there was antibiotic exposure during indwelling time (Escherichia/Shigella, Pseudomonas, Staphylococcus, Ureaplasma) and in those associated with infection (Escherichia/Shigella, Ureaplasma). The enriched interaction subnetwork in stent-associated infection included Ureaplasma and metabolite 9-methyl-7-bromoeudistomin. Strains identified as clinically relevant and central to interaction networks all reconstituted biofilm in vitro, with differential formation by strain (Enterococcus faecalis most) and material type (titanium least). Ureteral stent biofilms exhibit patterns unique to stent-associated infection and antibiotic exposure during indwelling time. Microbes isolated from stents reconstituted biofilm formation in vitro. This work provides a platform to test novel materials, evaluate new coatings for anti-biofilm properties, and explore commensal strain use for bacterial interference against pathogens.

Contamination with Enterococcus spp., strains of lettuces of different species acquired in Cumaná

Lettuce is one of the most common crops in the world, with high index of vitamins, minerals and fiber. Raw food consumption is closely related to foodborne illness, of which Escherichia coli O157:H7, seems to be the prime perpetrator leading to undesirable consequences. However, E. coli is not the only microorganism that can be transmitted, as reports validating the involvement of Aeromonas, Yersinia, Listeria, Staphylococcus, Campylobacter, and Salmonella have surfaced. The objective of this work was to detect the contamination of lettuces of different species acquired in several places of Cumaná, with Enterococcus strains. Of 52 lettuces acquired in food retail centers, 38% were contaminated with Enterococcus spp., strains. The best-selling lettuce was Lactuca sativa L. (25/52), but the most contaminated was Lactuca sativa var. capitata (89%). The highest average for Enterococcus was obtained in lettuces from Municipal Market. The dominant species of Enterococcus were E. faecalis (40%), and E. casseliflavus (30%); and to a lesser extent E. faecium (15%), E. gallinarum (10%), and E. avium (5%). The susceptibility profile showed that there are strains resistant to glycopeptides, fluoroquinolones, ansamycins, macrolides, phenols and tetracyclines. The clonal dissemination of two strains of E. faecalis and one strain of E. faecium by antibiotyping was demonstrated in lettuces from the municipal market. These results demonstrate that the food chain is a route of dissemination of multidrug resistant Enterococcus to the human intestinal microbiota, turning the gastrointestinal tract into a reservoir of intractable bacteria with the available antibiotics.

Enterococcus Species Isolated from Urine Cultures and Antibiotic Resistance Rates

While enterococci are found as flora elements in many parts of the body, they have recently emerged as different infectious agents such as urinary tract infections, bacteremia, and meningitis. Increasing antibiotic resistance also poses additional challenges in treatment. In this study, it was aimed to determine the species identification and antibiotic resistance rates of enterococci isolated from the urinary tract. Enterococcus strains isolated from urine culture samples sent to the routine microbiology laboratory from various clinics of our hospital between 01.01.2020 and 31.12.2021 with the preliminary diagnosis of urinary tract infection were included in this study. Samples were cultivated on sheep blood agar and eosin methylene blue agar, and species determination and antibiogram evaluation were carried out in accordance with the recommendations of EUCAST (European Committee on Antimicrobial Susceptibility Testing-2020-2021) using conventional methods and automated identification device (VITEK 2 Compact-BioMerieux-France). All enterococci isolates (n=349) were susceptible to vancomycin, teicoplanin, tigecycline and linezolid. Of Enterococcus faecalis isolates (n=238), 32.8% were resistant to ciprofloxacin, 23.7% to high-level gentamicin, 33.2% to imipenem, 2.5% to nitrofurantoin, and 26.9% to streptomycin. Of the Enterococcus faecium isolates (n=111), 84.7% were resistant to ciprofloxacin, 58.6% to high-level gentamicin, 91% to imipenem, 31.5% to nitrofurantoin, and 83.8% to streptomycin. In conclusion, it is important to determine the resistance patterns of enterococcus strains, which are most frequently isolated as the causative agent of urinary tract infection, and also cause other clinical presentations such as wound infection or bacteremia, and to establish appropriate treatment protocols and to determine new antibiotic resistances.

Infant food production environments: A potential reservoir for vancomycin-resistant enterococci non-nosocomial infections

Enterococcus has been considered one of the most important nosocomial pathogens for human infections, and the hospital environment is an important reservoir for vancomycin-resistant enterococci (VRE) that leads to antimicrobial therapeutic failure. However, infant foods and their production environments could pose risks for the immature population, while this question remains unaddressed. This study conducted an extensive and thorough Enterococcus isolation, VRE risk assessment of the Chinese infant food production chains and additional online-marketing infant foods, including powdered infant formula (PIF) and infant complementary food (ICF). To investigate the prevalence of Enterococcus along infant food chains and commodities, a total of 482 strains of Enterococcus, including E. faecium (n = 363), E. faecalis (n = 84), E. casseliflavus (n = 13), E. mundtii (n = 12), E. gallinarum (n = 4), E. hirae (n = 4), and E. durans (n = 2) were recovered from 459 samples collected from infant food production chains (71/254) and food commodities (67/205). A decreasing trend for Enterococcus detection rate was found in the PIF production chain (PIF-PC), particularly during the preparation of the PIF base powder (From 100 % in raw milk to 8.70 % in end products), while an increasing trend was observed in the ICF production chain (ICF-PC) mainly during the initial processing of farm crops and the further processing of the product (20 % at farm crops increasing to 76.92 % at end products). The result indicated that the PIF-PC process effectively reduced Enterococcus contamination, while the ICF-PC showed the opposite trend. Importantly, eleven VRE isolates were recovered from the infant food production chain, including seven E. casseliflavus isolates carrying vanC2/C3 and four E. gallinarum isolates carrying vanC1. Ten VRE isolates were from food production environments. Collectively, our study demonstrated that infant food production environments represent potential reservoirs for VRE non-nosocomial infections in vulnerable populations.

Targeting Enterococci with Antimicrobial Activity against Clostridium perfringens from Poultry

Necrotic enteritis (NE), caused by Clostridium perfringens, is an emerging issue in poultry farming. New approaches, other than antibiotics, are necessary to prevent NE development and the emergence of multidrug-resistant bacteria. Enterococci are commensal microorganisms that can produce enterocins, antimicrobial peptides with activities against pathogens, and could be excellent candidates for protective cultures. This study aimed to screen and characterize Enterococcus strains of poultry origin for their inhibitory activity against C. perfringens. In total, 251 Enterococcus strains of poultry origin plus five bacteriocin-producing (BP+) E. durans strains of other origins were screened for antimicrobial activity against the indicator C. perfringens X2967 strain using the "spot on the lawn" method. We detected thirty-two BP+ strains (eleven Enterococcus faecium, nine E. gallinarum, eight E. faecalis, three E. durans, and one E. casseliflavus). We further studied the antimicrobial activity of the supernatants of these 32 BP+ strains using agar well diffusion and microtitration against a collection of 20 C. perfringens strains. Twelve BP+ enterococci that were found to exhibit antimicrobial activity against C. perfringens were characterized using whole genome sequencing. Among these, E. faecium X2893 and X2906 were the most promising candidates for further studies as protective cultures for poultry farming. Both strains belong to the sequence type ST722, harbor the genes encoding for enterocin A and enterocin B, do not possess acquired resistance genes, do not carry plasmids, and present the acm gene, which is implicated in host colonization. Further research is needed to determine the utility of these strains as protective cultures.

Assessment of the Etiological Spectrum of Urinary Infections in Diabetic Patients and of the Resistance Patterns of the Uropathogenic Germs Involved

The aim of the retrospective-descriptive study consisted of the analysis of the spectrum of urinary infections and antimicrobial resistance of the uropathogenic bacteria involved in diabetic patients. The etiological spectrum was wide, being dominated by Escherichia coli (67,68%), Klebsiella sp. (14,14%), Proteus sp. (7,07%), and Enterococcus sp. (6,31%). Enterobacteriaceae had higher percentages of resistance to trimethoprim-sulphamethoxazole, quinolones, and cephalosporines, antibiotics frequently used in the therapy of urinary infections but also of other infections in diabetics. Over 50% of Enterococcus strains were resistant to fluoroquinolones. The detection of the carbapenem-resistant strains (imipenem – 8% and meropenem – 10,2%) is worrying. Colistin, carbapenems, and amikacin were most effective in vitro against Gram-negative bacilli and linezolid, vancomycin, and teicoplanin, in the case of Gram-positive cocci. The study results reveal the importance of monitoring the etiological spectrum and the resistance to antibiotics of the germs involved in urinary infections in diabetic patients, for the initiation of an effective therapy and the optimal management of the cases.

Glycosylated Lipopeptides—Synthesis and Evaluation of Antimicrobial Activity and Cytotoxicity

Ultrashort cationic lipopeptides (USCLs) are promising antimicrobial agents that may be used to combat pathogens such as bacteria and fungi. USCLs consist of a few basic amino acid residues and at least one lipid moiety, usually a fatty acid chain. Generally, USCLs are potent antimicrobials but their major shortcoming is a relatively high cytotoxicity and hemolytic activity. Glycopeptide antibiotics (e.g. vancomycin) are essential in combating bacterial infections and are popular in medicinal practice. However, literature concerning the effect of glycosylation of peptides on their antimicrobial activity is rather scarce. For the first time, this study highlights the effect of USCLs glycosylation on in vitro biological activity. The aim of this study was to evaluate the impact of glycosylation of a series of USCLs on antimicrobial activity, cytotoxicity and hemolytic activity. Straight-chain fatty acids (C14, C16, C18) were attached to the N-terminal amino group of tripeptides-SRR-NH2, RSR-NH2 and RRS-NH2. Two groups of the lipopeptides were synthetized, the first with unmodified L-serine (USCLs) and the other with L-serine O-glycosylated by N-acetyl-β-d-glucosamine to produce new class of glycosylated ultrashort cationic lipopeptide (gUSCLs). Both USCLs and gUSCLs were tested against planktonic and biofilm cultures of ESKAPE strains (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp.) and Candida glabrata, and hemolytic activity on human erythrocytes and cytotoxicity against the HaCaT cell line was examined. Generally, USCLs and gUSCLs proved to be active against all the tested strains. The highest activity displayed was by lipopeptides containing the C18 fatty acid. Antimicrobial, hemolytic and cytotoxic activities were mainly correlated with amino acid sequence (position of serine/glycosylated serine) and hydrophobicity of molecule and were found to be highly strain-dependent. In general, glycosylation did not guarantee an increased antimicrobial activity or a decreased hemolytic and cytotoxic activities. However, in some cases, gUSCLs proved to be superior to their USCLs analogs. The most pronounced differences were found for peptides with C18 fatty acid and serine at the first and second position against both planktonic cells and biofilm of C. glabrata, as well as the second and third position against S. aureus. It is noteworthy that gUSCLs were also more active against biofilm than were USCLs.

Anti-tumor effect of infant-derived Enterococcus via the inhibition of proliferation and inflammation as well as the promotion of apoptosis.

Probiotic Enterococcus hirae WEHI01 and Enterococcus faecium WEFA23 from infants were previously found to effectively inhibit the development of melanoma. In this study, their immunomodulatory and antitumor mechanisms were systemically studied. In vitro assay showed that E. hirae WEHI01 and E. faecium WEFA23 achieved biphasic immune regulation, which was revealed by the activation of resting spleen lymphocytes and RAW264.7 macrophages, as well as the anti-inflammation effect when immune cells were treated with LPS. The antitumor effects of E. hirae WEHI01 and E. faecium WEFA23 in vitro and vivo were then investigated. CCK8 and the cell scratch assay showed that the conditioned media, which were co-incubated with Enterococcus and spleen lymphocytes, significantly inhibited the proliferation and migration of B16F10, HepG-2 and HT-29 cells. The results of the tumor-bearing mice model experiment showed that E. faecium WEFA23 inhibition of the growth of tumors in mice, and the anti-tumor mechanism involved three aspects, namely tumor proliferation (decreasing expressions of LDHA, VEGF, MMP2, MMP9 and HIF-1α), inhibition of the pro-inflammation state (decreasing expressions of IL-6, TGF-β and IL-17) and the promotion of apoptosis (increasing expression of Bax/Bcl-2, caspase-3 and p53). The results suggest that the two strains of Enterococcus could be promising candidates for treating melanoma with a highly inhibitory effect.

Enterococos resistentes isolados de leite cru de ovelha e queijos da região Sul do Brasil

ABSTRACT: Enterococci have been used as sentinel organisms for monitoring antimicrobial resistance in food, humans, and other animals. In this sense, the present study evaluated the antimicrobial susceptibility profile and the presence of genes associated with resistance to erythromycin (msrC and ermB) and tetracycline [tet(M) and/or tet(L)] in enterococci isolated from raw sheep’s milk and cheeses (colonial, feta-, and pecorino-type) from South region of Brazil. A total of 156 enterococci were isolated from milk (n=80) and cheese (n=76) samples, identified by MALDI-TOF. Enterococcus faecalis (50.6%; n=79) was the most frequent species isolated from both samples. According to in vitro susceptibility tests, enterococci strains were not susceptible to the most commonly antimicrobial agents used in human and veterinary medicine. The frequency of MDR strains in enterococci isolated from milk (53.7%) was higher than those from cheese (24.2%). The tet(M) gene was the most commonly detected among tetracycline not-susceptible strains. The present study provided the first evidence of antimicrobial not-susceptible enterococci in raw sheep’s milk and cheeses in South Brazil. Drug-resistant strains, particularly those that are MDR, constitute a One Health issue.

Detection of Genes Related to Linezolid Resistance (poxtA, cfr, and optrA) in Clinical Isolates of Enterococcus spp. from Humans: A First Report from Iran.

Enterococci may develop resistance to linezolid through chromosomal mutations that involve specific linezolid resistance genes, such as cfr, optrA, and poxtA. The objective of this study was to evaluate the antibiotic susceptibility of enterococcal isolates and identify cfr, optrA, and poxtA genes in MDR isolates. Enterococcal isolates were collected from various clinical specimens at Al-Zahra, Amin, and Khorshid Hospitals in Isfahan. The Enterococcus isolates were identified as belonging to the E. faecalis and E. faecium species by using specific gene (D alanine D alanine ligase ddl) sets in PCR. To detect cfr, optrA, and poxtA genes among the species, a multiplex-PCR assay was performed. Out of 175 isolates, E. faecalis predominated 129/175 (73.7%). Furthermore, the prevalence of vancomycin-resistant Enterococci (VRE) and linezolid-resistant Enterococci (LRE) was 29.7% and 4%, respectively. The overall prevalence of MDR was 91.1%, 68.9%, and 66.6% of E. faecium, E. faecalis, and other Enterococcus spp., respectively. Interestingly, the frequency of optrA (71.4%) in E. faecium and poxtA and crf (42.8%) in E. faecalis were detected among LRE species. A statistically significant relationship (P < 0.05) was found between the presence of the three genes and the occurrence of LRE. This is the first study to report the detection of linezolid resistance genes (cfr, optrA, and poxtA) in clinical Enterococcus spp. isolates from Iran, conducted at Isfahan University of Medical Sciences hospitals. The emergence of enterococcal strains that resist linezolid is concerning as it can lead to the spread of resistant strains among patients, resulting in treatment failure.

PREVALENCE OF VANCOMYCIN RESISTANT ENTEROCOCCI FROM URINARY TRACT INFECTED PATIENTS

Urinary tract infections (UTIs) are one of the infectious diseases affecting humankind. The microbial agents that infect the tissues of the urinary tract from the renal cortex to the urethral meatus Enterococci are opportunistic pathogens that are found in the normal gut flora. Enterococci are the second leading cause of UTIs, accounting for 10% of all nosocomial UTIs. This species has become a major pathogen in the United States, Iran, Europe, and other parts of the world, including India. Antibiotic resistance is increasing, which slows the rate of progress in practical therapies, making susceptibility testing necessary. So, enterococci were isolated from urine samples of patients with UTI that were subjected to morphological characterization, biochemical assays, etc., The main aim of the study was to help in identifying resistance patterns and the dispersal of Enterococcus strains from various samples of urine to antibiotic agents like Penicillin G, Tetracycline, Teicoplanin, Norfloxacin, high-level Gentamycin, Linezolid, Nitrofurantoin, and with special emphasis on Vancomycin antibiotic. The greatest threat posed by Vancomycin-Resistant Enterococci (VRE) is its ability to transfer resistance genes to more dangerous gram-positive bacteria, potentially leading to truly terrifying pathogens in the future. A long stay in the hospital and the use of Vancomycin were connected to VRE-UTI and colonisation. Renal dialysis, renal failure, previous aminoglycoside, and third-generation cephalosporin use were all relevant hazard factors for VRE from UTI. The paper also underlines the importance of screening clinical samples for VRE and proposes that control measures be implemented to limit the spread of VRE.

Virulence genes and antimicrobial resistance in Enterococcus strains isolated from dogs and cats in Northeast China.

This study aimed to characterize the antimicrobial resistance and virulence of Enterococcus from dogs and cats in Northeast China and evaluate its zoonotic risk based on a total of 469 enterococci strains from 610 samples, including 238 strains of E. faecium and 128 strains of E. faecalis. The isolation rate from police dog samples was 93.79%, pet dog samples was 69.90% and pet cat samples was 76.67%. The differences in the prevalence of E. faecalis among different hosts were statistically significant (P<0.05). The assays showed that most of the virulence genes detected were existed in E. faecalis and police dogs carried the least number of virulence genes. The correlation between enterococcal surface protein (esp) and aggregation substance (asa1) was determined. Enterococci are most resistant to tetracycline and erythromycin, 68.92% of the isolates were classified as multiple drug resistant. Significant differences (P<0.01) were found between E. faecium and E. faecalis in the resistance rates of nine antimicrobials. Four positive and four negative correlations were found between virulence genes and antimicrobial resistance. The results show that Enterococcus colonization and excretion in dogs and cats were related to animal species and living environments. Some correlation between virulence factors and antimicrobial resistance was obtained. This study confirmed the presence of strains carrying multiple virulence factors and antimicrobial resistance at the same time, suggesting a public health risk for dogs and cats as reservoirs of enterococci.

154. Prevalence and Antimicrobial Resistance of Enterococcus species in a Tertiary Center Children’s Hospital in Korea

Abstract Background Increasing prevalence of Enterococcus spp. as a nosocomial pathogen with high-level resistance to multiple antimicrobials has been a challenge throughout the years, and now, even to the pediatric age. This study is a pioneer research which was designed to determine the prevalence of different antibiogram patterns of enterococcal strains in the pediatric age. Methods In this retrospective review, we included Enterococcus species isolated from normal body fluid including blood and CSF from March 2014 through September 2020 at Asan Medical Center Children`s Hospital. Electronic Medical Records (EMR) was reviewed for clinical and demographic data. Results A total of 205 different clinical strains of Enterococcus species were collected. Isolated strains were E. faecalis (47.3%), E. faecium (41.5%), E. avium (4.9%), E. gallinarum (2.9%), E. raffinosus (2.0%) and others (1.5%). No strains were resistant to linezolid. Vancomycin or teicoplanin resistant strains were 26.3% (vancomycin 17.1%, teicoplanin 9.3%), most of which were E. faecium (vancomycin 13.7%, teicoplanin 9.3%). Ampicillin or penicillin resistant strains were 82.9% (ampicillin 39.0%, penicillin 43.9%), most of which were also E. faecium (ampicillin 35.1%, penicillin 36.1%). High-level streptomycin or gentamicin resistant strains were 46.8% (streptomycin 13.2%, gentamicin 33.7%), mostly E. faecalis (streptomycin 7.8%, gentamicin 19.0%). The prevalence of antimicrobial resistance differed significantly between E. faecalis and E. faecium; E. faecalis being nearly all susceptible to ampicillin and penicillin except 6 strains which was an interesting finding because ampicillin-susceptible, penicillin-resistant E. faecalis strains were found. Antibiotic Resistance Pattern of Enterococcal Strains MIC of ASPR Enterococcus species by Etest Conclusion Consistent findings with previous studies based on adults are that E. faecalis and E. faecium were the predominant strains causing infection in children as well. There are reports about currently emerging ampicillin-susceptible but penicillin-resistant(ASPR) E. faecalis strains which were also found in this study and so therefore further molecular studies about this newly emerging ASPR E. faecalis is in progress. Disclosures All Authors: No reported disclosures.

Determination of safety status and probiotic properties ofEnterococcusstrains isolated from traditional cheeses in Turkey

This study aimed to evaluate the probiotic properties of Enterococcus strains isolated from Turkish traditional cheeses. Fifty-two Enterococcus spp. were taxonomically determined as follows: Enterococcus faecium (26), Enterococcus faecalis (18), Enterococcus durans (6), and Enterococcus italicus (2). The ability of isolates/strains to survive the harsh conditions (acidity and in-vitro gastric solution) of the gastrointestinal tract was established. They also showed auto-aggregation, hydrophobicity, and co-aggregation ability. Hydrophobicities of the strains were found between 0.8%-21%, 0.7%-56%, and 2%-63% for xylene, chloroform, and ethyl acetate, respectively. Autoaggregation values of the Enterococcus strains were 4%-20%, 7%-30%, and 36%-98% after 2, 4, and 24-h incubation, respectively. In this study, the Enterococcus strains tested showed co-aggregation ability with the Escherichia coli ATCC 25922, Salmonella Typhimurium ATCC 14028, and Staphylococcus aureus ATCC 25923. The results of PCR amplification revealed that only five strains possess virulence factor genes (gelE,asa1,cyl A,esp). We determined antibiotic resistance, biofilm forming abilities, and hemolytic activity for safety evaluation of strains. In this large and comprehensive study, we found that only few of Enterococcus strains have promising probiotic potential, among which E. faecalis ES1 and E. faecium EM1 showed the best probiotic properties (are the most promising probiotic candidates).

Antibiotic Resistance of Enterococcus spp. Isolated from the Urine of Patients Hospitalized in the University Hospital in North-Central Poland, 2016-2021.

Urinary Tract Infections (UTIs) are common outpatient and inpatient infections, often treated with empirical therapy. Enterococcus spp. is responsible for about 10% of UTIs. This study aimed to determine the necessity of changing the empirical treatment of UTIs caused by Enterococcus spp. The evaluation was performed for 542 Enterococcus strains isolated from urine samples in the years 2016-2021. We identified three Enterococcus species that were found: E. faecalis (389, 71.8%), E. faecium (151, 27.8%) and E. gallinarum (2, 0.4%). E. faecalis was the dominant species every year. Among E. faecalis, the most prevalent was resistance to norfloxacin (51.4%). Almost all E. faecium strains (150, 99.3%) were resistant to beta-lactams and norfloxacin. Eighty-three strains (55.0%) were resistant to vancomycin and 72 (47.7%) to teicoplanin. E. faecium strains showed a significantly higher percentage of resistance mechanisms GRE (Glicopeptide-Resistant Enterococcus) (72, 48.7%) and VRE (Vancomycin-Resistant Enterococcus) (11, 7.3%), while only five strains of E. feacalis showed a VRE mechanism (1.3%). In the therapy of E. faecalis UTIs, ampicillin and imipenem still remain effective. However, the above-mentioned antibiotics, as well as fluoroquinolones, are not recommended in the treatment of UTIs of E. faecium etiology.

Characteristics of Lactic Acid bacteria isolated from traditional fermented fish

Abstract. Novia R, Ardiningsih P, Adhityawarman, Sarwiyati. 2022. Characteristics of Lactic Acid bacteria isolated from traditional fermented fish. Biodiversitas 23: 5662-5669. Lactic acid bacteria (LAB) are commonly involved in most food fermentation and contribute to the process’s quality and safety. The study investigates the characteristics of LAB isolated from buduk, pekasam, and pekasam ale-ale. Twelve colonies each sample were isolated and identified based on morphology and biochemical test. The pekasam ale-ale isolates were identified as Pediococcus sp. strain A1 and Pediococcus sp. strain A3; Enterococcus sp. strain A2 and Enterococcus sp. strain A4. The LAB in buduk were identified as Streptococcus sp. strain B1, Pediococcus sp. strain B2 and Pediococcus sp. strain B4, Enterococcus sp. strain B3. The pekasam isolates were identified as Pediococcus sp. strain P1, Streptococcus sp. strain P2 and Streptococcus sp. strain P4, Lactobacillus sp. strain P3. The LAB showed antimicrobial activities while Lactobacillus sp. strain P3 and Streptococcus sp. strain P4 could grow at pH 1. Two LAB including Enterococcus sp. strain A2 and Pediococcus sp. strain P1 showed amylase activity while Pediococcus sp. strain A3, Streptococcus sp. strain B1, Pediococcus sp. strain B2, Enterococcus sp. strain B3 showed protease activity. All LAB produced organic acids with varying concentrations at different incubation times. Furthermore, those isolated from various fish fermentations showed different genera and characteristics. Lactobacillus sp. strain P3 was the best to initiate food fermentation and a probiotic candidate based on their characteristics.

Development of Bioactive Opuntia ficus-indica Edible Films Containing Probiotics as a Coating for Fresh-Cut Fruit.

Bioactive edible films have received more attention in recent years as a method for food preservation with value-added functions. The aim of this study was to develop a bioactive edible film containing mucilage of cactus (Opuntia ficus-indica) and incorporating the probiotic strain Enterococcus faecium FM11-2 as an active component to promote consumer health benefits. Opuntia ficus-indica is rich in nutritional and bioactive compounds and the abundance of this cactus makes it attractive for food applications. Mucilage of Opuntia ficus-indica contained 0.47 ± 0.06 mg/g total sugar, 0.33 ± 0.06 mg AGE/mL phenolic content, 0.14 mg/ mL vitamin C, and possessed 35.51 ± 1.88% DPPH scavenging activity. The edible film that was developed exhibited the following characteristics: thickness of 0.02-0.11 mm, percent moisture content 0.19-0.24%, water solubility 30.66-59.41% and water vapor permeability of 0.15-1.5 g·mm/m2·min·kpa, while the range of the variation depended on the type of plasticizer used (either sorbitol or glycerol). The addition of sorbitol in the film provided the maximum mechanical strength based on the evaluation of tensile strength, Young's modulus and elongation at break (44.71 ± 0.78 MPa, 113.22 ± 0.23 MPa and 39.47 ± 0.61%, respectively). The optimal formulation of the edible film, according to the physicochemical, physical and maintenance of fresh-cut apple slices, contained cactus mucilage, gelatin, glycerol and a probiotic. The incorporation of a probiotic into the cactus film created a bioactive edible film that could provide a health benefit. While improvement is needed to maintain the survival rate of the probiotic, this work presents an exciting method for furthering the study of food preservation with edible films.

Isolation and characterization of a novel human intestinal Enterococcus faecium FUA027 capable of producing urolithin A from ellagic acid.

Urolithin A (UA) has received considerable research attention because of its health benefits. However, only a few strains have been reported to produce UA from ellagic acid (EA), and the molecular mechanisms underlying the gut microbiota-mediated transformation of ellagic acid into urolithin A is limited. In the present study, a single strain FUA027 capable of converting ellagic acid into UA in vitro was isolated from the fecal samples. The strain was identified as Enterococcus faecium through the morphological, physiological, biochemical and genetic tests. UA was produced at the beginning of the stationary phase and its levels peaked at 50 h, with the highest concentration being 10.80 μM. The strain Enterococcus faecium FUA027 is the first isolated strain of Enterococcus sp. producing urolithin A from ellagic acid, which may be developed as probiotics and used to explore molecular mechanisms underlying the biotransformation of ellagic acid into UA.

Are Enterobacteriaceae and Enterococcus Isolated from Powdered Infant Formula a Hazard for Infants? A Genomic Analysis.

Powdered infant formulas (PIF) are the most used dietary substitutes that are used in order to supplement breastfeeding. However, PIF are not sterile and can be contaminated with different microorganisms. The objective of this study was to genomically characterize Enterobacteriaceae (ENT) and Enterococcus strains that were isolated from PIF. Strains were identified by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and whole-genome sequencing (WGS). Genomic typing, detection of virulence, and resistance profiles and genes were performed with the Ridom SeqSphere+ software; the comprehensive antibiotic resistance database (CARD) platform; ResFinder and PlasmidFinder tools; and by the disk diffusion method. Nineteen isolates from PIF were analyzed, including ENT such as Kosakonia cowanii, Enterobacter hormaechei, Franconibacter helveticus, Mixta calida, and lactic acid bacteria such as Enterococcus faecium. The strains exhibited resistance to beta-lactams, cephalosporins, and macrolides. Resistance genes such as AcrAB-TolC, marA, msbA, knpEF, oqxAB, fosA, blaACT-7, blaACT-14,qacJ, oqxAB,aac(6')-Ii, and msr(C); and virulence genes such as astA, cheB, cheR, ompA ompX, terC, ironA, acm, and efaAfm, adem were also detected. All the analyzed strains possessed genes that produced heat-shock proteins, such as IbpA and ClpL. In PIF, the presence of ENT and Enterococcus that are multiresistant to antibiotics-together with resistance and virulence genes-pose a health risk for infants consuming these food products.