Enterococcus faecium from meat, chicken and cheese

Background: Vancomycin-resistant enterococci (VRE) are important nosocomial pathogens and food chain has been considered as an assumed source for dissemination of VRE to human. Objectives: The presence of VRE isolates from food samples and typing of these isolates with Phene plate, a biochemical fingerprinting method, were investigated. Materials and Methods: Thirty samples of meat, chicken and cheese were analyzed for VRE during 2010. Antibiotic susceptibility tests and minimum inhibitory concentration (MIC) were also examined. VRE isolates were typed with the Phene plate system (PhPlate), a biochemical fingerprinting method. Results: A total of 70 VRE isolates were obtained and identified as Enterococcus faecium by species-specific PCR. All the isolates carried vanA, while none of them harbored vanB. The VRE isolates included 35, 27, and 8 isolates from meat, chicken and cheese, respectively. Typing with the PhPlate revealed a diversity index of 0.78 for E. faecium, containing 10 common and four single types. The results of antibiotic susceptibility and MIC tests showed an increased resistance to ciprofloxacin, erythromycin, ampicillin and gentamicin, to which, 100, 100, 100, and 95 of VRE isolates were resistant, respectively. Only 5 of the isolates were resistant to chloramphenicol and the MIC of the isolates for vancomycin and teicoplanin was � 256 μg/mL and for gentamicin-resistant isolates it was 1024 μg/mL. Conventional and molecular identification tests exhibited that all the isolates were E. faecium carrying vanA. None of the isolates harbored vanB. Conclusions: The results showed that enterococci are common contaminants in food. Indeed, this study indicates a high prevalence of multidrug-resistant enterococci in food of animal origin in Iran. Isolating some persisting enterococcal isolates revealed that continuous surveillance of antimicrobial resistance in enterococci from food is essential. © 2015, Ahvaz Jundishapur University of Medical Sciences

Highly heterogeneous probiotic Lactobacillus species in healthy iranians with low functional activities

Background Lactic acid bacteria (LAB) have been considered as potentially probiotic organisms due to their potential human health properties. This study aimed to evaluate both in vitro and in vivo, the potential probiotic properties of Lactobacillus species isolated from fecal samples of healthy humans in Iran. Methods and Results A total of 470 LAB were initially isolated from 53 healthy individual and characterized to species level. Of these, 88 (86) were Lactobacillus species. Biochemical and genetic fingerprinting with Phene-Plate system (PhP-LB) and RAPD-PCR showed that the isolates were highly diverse consisted of 67(76.1) and 75 (85.2) single types (STs) and a diversity indices of 0.994 and 0.997, respectively. These strains were tested for production of adhesion to Caco-2 cells, antibacterial activity, production of B12, anti-proliferative effect and interleukin-8 induction on gut epithelial cell lines and antibiotic resistance against 9 commonly used antibiotics. Strains showing the characteristics consistent with probiotic strains, were further tested for their anti-inflammatory effect in mouse colitis model. Only one L. brevis; one L. rhamnosus and two L. plantarum were shown to have significant probiotic properties. These strains showed shortening the length of colon compared to dextran sulfate sodium and disease activity index (DAI) was also significantly reduced in mouse. Conclusion Low number of LAB with potential probiotic activity as well as high diversity of lactobacilli species was evident in Iranian population. It also suggest that specific strains of L. plantarum, L. brevis and L. rhamnosus with anti-inflammatory effect in mouse model of colitis could be used as a potential probiotic candidate in inflammatory bowel disease to decrease the disease activity index. © 2015 Rohani et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Antibiotic resistance and biofilm formation of Enterococcus faecalis in patient and environmental samples

Background: Enterococci are opportunistic pathogens and are a major factor in nosocomial infections. They may contain ebp operon, which upon expression makes them highly prone to biofilm formation on biotic and abiotic surfaces. Objectives: The aim of the current study was to detect the polymorphism of ebp genes in Enterococcus faecalis. Materials and Methods: Samples were isolated from patients (n = 58) and hospital environments (n = 32) of two hospitals in Tehran, Iran. All enterococcal species were identified by species-specific polymerase chain reaction (PCR); the antibiotic resistance pattern against nine antibiotics was determined. The ebp A, ebp B, ebp C and srt C genes were detected by PCR and the biofilm formation by the isolates was evaluated using the microtiter plate method. The genetic diversity of ebp genes was analyzed by restriction fragment length polymorphism (RFLP). Results: The results indicated that, 86 of patient and 29 of environmental isolates carried ebp genes. The ability of the isolates to strongly attach was 62 and 71 for patient and environmental samples, respectively. The RFLP of the ebp showed no genetic variations amongst the isolates. Conclusions: The results of the antibiotic resistance and other data suggest that there is a possible common clone of E. faecalis, which could rapidly disseminate in patients and the environment. © 2015, Ahvaz Jundishapur University of Medical Sciences

In vitro antifungal activity of various persian cultivars of Punica granatum L. Extracts against Candida species

Background: Resistance of Candida species to antifungal agents has potentially serious implications for management of infections. Candida species are now the fourth most common organisms isolated from hospitalized patients. Prevention and control of these infections will require new antimicrobial agents. Plant-derived antifungal agents have always been a source of novel therapeutics. Objectives: The aim of this study was to investigate the antifungal effect of pomegranate peel and pulp extracts against Candida species. Materials and Methods: Pomegranate pulp and peel were dried and powdered separately. The dried powders were extracted using a soxhlet extractor. The antifungal effect of pomegranate peel and pulp extracts were determined in vitro by using the minimum inhibitory concentration (MIC) against five standard species, including Candida albicans (ATCC 10231), Candida parapsilosis (ATCC 22019), Candida tropicalis (ATCC 750), Candida glabrata (PTCC 5297) and Candida krusei (PTCC 5295). Results: Maximum inhibitions were attributed to peel extract of the pomegranate cultivar against Candida species. The greatest antifungal inhibition among the eight different cultivars was observed for sour malas, sour white peel and sour summer extracts respectively, against the five Candida strains. The antifungal activity of pulp extracts against Candida species was somewhat negative. Conclusions: Our work suggested that pomegranate (Punica granatum L.) peel has potential antifungal activity against Candidiasis, and it is an attractive option for the development of new management strategies for candidiasis. � 2015, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences

Screening for probiotic characters in lactobacilli isolated from chickens revealed the intra-species diversity of Lactobacillus brevis

Considering the importance of the poultry industry and the increasing interest in alternative growth promoters, probiotics are considered as a potential candidate for use in the poultry industry. In this study, Lactobacillus species were isolated from 21 rectal swabs of 11 healthy 6-day-old and 10 healthy 21-day-old chickens and their fecal and feed samples. The isolates were characterized and their probiotic characteristics, including resistance to gastric acid and bile salts, biofilm formation and adherence to epithelium or mucus, amylase and protease activity and production of inhibitory compounds, were assessed. From 31 acid and bile resistant lactobacilli, only 2 Lactobacillus brevis and 1 Lactobacillus reuteri strains showed significant probiotic properties. These isolates indicated detectable attachment to Caco-2 cells and significant antibacterial activities against Gram-positive and Gram-negative pathogens. Additionally, phenotypic and genotypic diversity of lactobacilli isolates were studied by Phene Plate (PhP) system (PhP-LB) and random amplified polymorphic DNA (RAPD)-PCR, respectively. PhP-LB results of 24 L. brevis isolates showed a high phenotypic variation among the isolates. In comparison, results of RAPD-PCR highlighted a low diversity. Therefore, it seems that combination of the 2 techniques (PhP and RAPD-PCR) could result in a significant discriminatory power than each of them used alone. © 2021 Chinese Association of Animal Science and Veterinary Medicin

Resistance-gene cassettes associated with Salmonella enterica genotypes

Background: The epidemiology of salmonellosis is complex because of the diversity and different serotypes of Salmonella enterica (S. enterica) that occur in different reservoirs and geographic incidences. Objectives: To determine the genotype distribution and resistancegene content of 2 classes of integron among S. enterica isolates. Methods: Thirty-six S. enterica species were isolated and tested for their serological distribution and the resistance-gene contents of 2 classes of integron, as well as for their genetic diversity, using the pulsed-field gel electrophoresis (PFGE) genotyping method. Results: Serogroups E (36.1) and D (30.5) were dominant among the isolates. All of the isolates in serogroup D belonged to the serovar enteritidis. The aadA1 gene was found within all resistance-gene cassettes. We observed 4 common and 26 single pulsotypes among the isolates, which indicated a high degree of genetic diversity among the isolates. Using the PulseNet International standard protocol, it was found that these isolates were different from those reported previously in Iran. Conclusions: The presence of a few common and new pulsotypes among the isolates suggests the emergence and spread of new clones of S. enterica in Iran

Screening for efficient nitrogen sources for overproduction of the biomass of the functionally probiotic L. plantarum strain RPR42 in a cane molasses-based medium

Nitrogen source has a vital role for the efficient growth of lactobacilli. The effects of cheese whey, corn steep liquor, and wheat germ extract on the growth of L. plantarum strain RPR42 in cane molasses-based media was evaluated using various approaches of design of experiments. Our results showed that such protein-rich agricultural by-products significantly increase the biomass production of the strain RPR42 in cane molasses-based media. The most affecting nitrogenous material was cheese whey followed by CSL and the minor effect was reported for wheat germ extract as revealed in factorial and Box�Behnken design experiments. The replacement of costly beef extract and yeast extract with a defined mixtures of the above nitrogenous agricultural by-products in cane molasses-based medium led to production of up to 12.64 g/L/24 h of dry biomass of strain RPR42. A detectable cell density of strain RPR42 (~ 9.81 � 109 CFU/mL 24 h) which was observed in such an economic medium showed that the large-scale production of the strain RPR42 tend to be feasible at significantly low costs. © 2020, The Author(s)

Determination of characteristics of erythromycin resistant Streptococcus pneumoniae with preferred PCV usage in Iran

Amongst 100 Streptococcus pneumoniae isolated from clinical cases and nasopharynx of healthy individuals, 60 erythromycin resistant strains were isolated and characterized using MLST, PFGE, transposon analysis and Quellung reaction. Most of the S. pneumoniae erythromycin resistant (80) were found to be attributable to the ermB-edncoded ribosome methylase activity which differs from the dominant mechanism of macrolide resistance seen in North America. The most predominant transposons were; Tn 1545/6003(27), Tn6002 (22), Tn2009 (20), Tn2010 (17). Number of the clinical isolates carrying Tn2010 was more significant than the normal flora. The serotypes found were; 14 (33), 3 (22), 23F (15), 19F (15), 19A (7), 6A (3), 9V (3) and 6B (2). The most prevalent serotypes among the clinical (n = 28) and normal flora (n = 32) isolates were serotypes 14 (46) and 3 (31), respectively. The most prevalent vaccine serotypes amongst the clinical isolates and the healthy individuals were pneumococcal conjugate vaccines (PCV) 13 and PCV10, respectively. PFGE revealed 34 pulsotypes with 9 common and 25 single types. Significant number of the normal isolates belonged to CT5 and CT6. On the other hand, significant number of clinical isolates belonged to CT8 as compared to the normal flora isolates. MLST showed 2 dominant sequence types. ST3130 (23) and ST180 (22) were the most predominant sequence types in the clinical and normal isolates, respectively. There was no significant difference in other sequence types between clinical and normal flora isolates. Three polyclonal complexes including Sweden15A -25, Spain23F-1 and Spain9V-3 constituted 58 of the isolates. Our results suggest that the genetic diversity and transposon distribution were high among S. pneumoniae, particularly in the isolates containing erm(B) and double antibiotic resistant genes (erm/mef). The results presented here could influence the change in the current vaccination practices in Iran which currently calls for vaccination with PCV7 or PCV10. � 2016 Talebi et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited