Presumptive Isolates Research Articles

Detection of Lactobacillus in Pork and Traditional Pork Products of Mizoram, India and Evaluation of its Probiotic Characteristics

Background: Sa-Um, a traditional pork product of Mizoram could be an alternative and easily available source for Lactobacillus starter culture with probiotic properties. Methods: Traditional pork product (Sa-Um) and pig faecal samples from Mizoram were collected and analysed for number of viable Lactobacillus bacteria by spread plate method. Samples above 106 cfu/ ml were considered for isolation of probiotics. Gram positive and catalase negative presumptive Lactobacillus isolates were confirmed by PCR analysis of 16S-rRNA gene. The Lactobacillus strains were studied for viability at different temperatures, species identification by fermentation of sugars and probiotic properties namely tolerance to acid, bile salt and digestive enzymes, antagonistic activity and antimicrobial sensitivity. Result: Four Lactobacillus strains, namely L. plantarum SU 2, L. plantarum SU 11 and L. acidophilus SU 38 from Sa-Um and L. plantarum PF 11 from pig faeces were suggested as probiotic bacteria. Lactobacillus plantarum SU 2 was the most potential probiotic candidate based on the studied probiotic properties.

Identification, safety and technological characteristics of Weissella strains from traditional Southwestern Algerian kaddid

Kaddid is a dry-fermented meat product traditionally produced in North Africa by spontaneous fermentation. As a reservoir of natural biodiversity, the identification and relevant traits of lactic acid bacteria (LAB) were carried out from South-western Algeria homemade samples. After a preliminary physiological and biochemical screening, 19 presumptive LAB isolates were selected on the basis of antimicrobial compounds production. The isolates were identified by 16S rRNA gene sequencing as Weissella cibaria, W. confusa, W. paramesenteroides, Pediococcusacidilactici, and Enterococcus hirae. As predominant, the safety and technological characterization of Weissella strains were performed. The production of antimicrobial and antifungal compounds was observed, while neither H2S, biogenic amines nor hemolytic activity were detected; antibiotic resistance was exhibited, however several strains were more susceptible to assayed antibiotics. Technological characterization of Weissella strains showed high acidification rates even in the presence of up to 10 % NaCl, autolytic and proteolytic capacity however, no EPS production and lipolytic activity were observed. Strains characterization led to the selection of W. cibaria BK2, W. confusa BK6 and BK11 as well as W. paramesenteroides BK8 to be considered as possible candidates for use as starter culture for kaddid fermentation to improve and standardize this traditional meat product.

Occurrence and Antibiotic Resistance Profiles of Methicillin-Resistant Staphylococcus Aureus (Mrsa) in Layer Chickens in Kebbi, Nigeria

Abstract Antimicrobial resistance (AMR) is a global health threat, and antimicrobial use in animal production for growth enhancement or prophylaxis contributes to the development of AMR. A cross-sectional study was conducted to investigate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in poultry and farm attendants in Kebbi, North-Western Nigeria. A total of 207 cloacal and nasal swabs were randomly collected from four farms comprising 50 samples from each poultry farm and only 7 samples from farm attendants. The samples were analysed using routine bacteriological culture and identification techniques. Presumptive MRSA isolates were confirmed by PCR assay and AMR profiles of the isolates were evaluated using the Kirby-Bauer disk diffusion method. Of the 207 samples examined, 37.5 % (75/200) of layer birds tested positive for MRSA and 71.4 % (5/7) of farm attendants were MRSA positive. All the isolates were susceptible to vancomycin, with an AMR index ˃ 0.3. The findings of this study indicated colonization of layer chickens and humans by multidrug resistant MRSA, thus highlighting the potential role of poultry sources of transmission of multidrug-resistant MRSA strains to humans and vice versa.

Prevalence of methicillin resistance in Staphylococcus pseudintermedius isolates from dogs with skin and ear infections in South Africa

Staphylococcus pseudintermedius (SP) is an important opportunistic pathogen, frequently associated with pyoderma and otitis in dogs. The emergence and rapid expansion of methicillin-resistant Staphylococcus pseudintermedius (MRSP) is problematic due to multidrug resistance and reduced treatment options. The aim of this study was to determine i) the prevalence of MRSP in dogs with pyoderma or otitis externa, ii) the antimicrobial resistance patterns of MRSP from South African isolates, and iii) the risk factors for MRSP-associated pyoderma or otitis externa in dogs in South Africa (RSA). Sixty-eight presumptive clinical SP isolates (collected from 65 dogs) from five geographically dispersed laboratories in RSA were collected over 2 years. Possible MRSP isolates were flagged when resistance to oxacillin was observed. Thereafter, all isolates were confirmed as SP by polymerase chain reaction (PCR) and further genotyped for the mecA gene. Fifty-seven of 68 isolates were confirmed to be SP (83.8%), while 49/57 (85.9%) carried mecA. Our findings showed that preliminary phenotypic methods supplemented by genotypic methods increased the accuracy of correctly identifying SP. All isolates were resistant to at least one antimicrobial drug. There was a high incidence of amoxicillin (70.1%) and enrofloxacin (65%) resistance. Important risk factors for mecA positive carriage were previous hospital admission, pruritus, and previous antibacterial failure. This study demonstrates a high prevalence of mecA positive carriage (85.9% of samples) in MRSP pyoderma and otitis in dogs in RSA. There is an urgent need for better laboratory diagnosis of MRSP and surveillance of dogs presenting with pyoderma and otitis in South Africa.

Isolation and Identification of Lactose-Degrading Yeasts and Characterisation of Their Fermentation-Related Ability to Produce Ethanol

Kefir is traditionally produced by fermenting cow’s milk using kefir grains as a starter culture. As the viability of microbes within kefir grains is limited and preparing the grains for kefir fermentation is laborious, here, a single starter that ferments lactose and produces ethanol is developed. For this purpose, it is important to isolate yeasts that can ferment lactose and subsequently produce alcohol. This study aimed to isolate and identify yeasts from kefir and characterise their ability as single starters to produce kefir. Based on morphological and physiological evaluations, 15 presumptive yeast isolates were obtained, 10 of which grew well on lactose-containing media. Those that were able to grow on lactose using only carbon sources were subjected to molecular identification based on the internal transcribed spacer (ITS) of the 5.8 rDNA using PCR technology. Molecular identification confirmed four isolates—namely, KFA 3, KFA 7, KFA 9 and KFB 1—as belonging to Kluyveromyces marxianus. The batch fermentation data of these strains were fitted on a logistic model to obtain the carrying capacity coefficients and strain performances were compared. The kinetic modelling revealed that KFA 9 had the highest values for the carrying capacity coefficient, biomass yield and product yield, indicating that, among the four K. marxianus strains, this was superior due to its relatively fast growth and good ethanol productivity.

In Vitro and in Vivo Activity of Lactobacillus Sakei L14 Strain Against Campylobacter Jejuni DC3 Strain.

IntroductionDomestic poultry is a natural reservoir of Campylobacter, the host–pathogen interaction being predominantly asymptomatic. This study investigated whether chickens remain asymptomatic partly because of lactic acid bacteria (LAB).Material and MethodsCampylobacter spp. and LAB were isolated from the gut of poultry chickens using enrichment and screening assays and were identified via rDNA sequencing. The C. jejuni DC3 isolate was grown in different cell-free supernatants (CFS) generated from a priority LAB isolate. An in vivo challenge involving the C. jejuni and LAB isolates using a chicken model was performed to confirm the in vitro findings.ResultsTwelve presumptive LAB isolates had anti-C. jejuni activity based on cross-streak and agar plug assays, with Lactobacillus sakei L14 isolate exhibiting the highest activity. Inhibition by L. sakei L14 CFS of the growth of C. jejuni occurred in a dose-dependent manner. Campylobacter jejuni DC3 inhibition was most evident in CFS harvested at 72 h and produced by co-culture with the pathogen. Neutralisation of the CFS abrogated the observed inhibition. Co-infection with C. jejuni DC3 and L. sakei L14 in vivo, however, failed to inhibit C. jejuni colonisation in chickens.ConclusionThe results suggest that the anti-C. jejuni effect of L. sakei L14 in chickens may be due to mechanisms other than direct inhibition of growth.

Development of duplex qPCR targeting Carnobacterium maltaromaticum and Vagococcus salmoninarum.

In November 2018, Vagococcus salmoninarum was identified as the causative agent of a chronic coldwater streptococcosis epizootic in broodstock brook trout (Salvelinus fontinalis) at the Iron River National Fish Hatchery in Wisconsin, USA. By February 2019, the epizootic spread to adjacent raceways containing broodstock lake trout (Salvelinus namaycush), whereby fish were found to be coinfected with Carnobacterium maltaromaticum and V.salmoninarum. To differentiate these two pathogens and determine the primary cause of the lake trout morbidity, a quantitative real-time PCR (qPCR) was developed targeting the C.maltaromaticum phenylalanyl-tRNA synthase alpha subunit (pheS) gene. The qPCR was combined with a V.salmoninarum qPCR, creating a duplex qPCR assay that simultaneously quantitates C.maltaromaticum and V.salmoninarum concentrations in individual lake trout tissues, and screens presumptive isolates from hatchery inspections and wild fish from national fish hatchery source waters throughout the Great Lakes basin. Vagococcus salmoninarum and C.maltaromaticum were co-detected in broodstock brook trout from two tribal hatcheries and C.maltaromaticum was present in wild fish in source waters of several national fish hatcheries. This study provides a powerful new tool to differentiate and diagnose two emerging Gram-positive bacterial pathogens.

Occurrence of New Delhi Metallo-Beta-Lactamase 1 Producing Enterococcus Species in Oghara Water Nexus: An Emerging Environmental Implications of Resistance Dynamics.

Various members of the enteric bacteria in recent times are evolving diverse survival mechanisms for antibiotic therapy resulting in failure of treatment in infection and disease cases. The Enterococcus species are potential strains implicated in gastrointestinal tract infection and are recently evolving in the resistance mechanism. The study evaluates the occurrence of New Delhi Metallo-beta-lactamase 1 (NDM-1) amongst Enterococcus species using the phenotypic and genomic characterization of environmental strains in the Oghara water nexus. Presumptive isolates of Enterococcus species were retrieved from various sampled water sources and confirmed using polymerase chain reaction (PCR). Antibiotic susceptibility testing was conducted on confirmed isolates using Kirby-Bauer disk diffusion methods. The result reveals 63 genus isolates confirmed Enterococcus species, of which 42 (67%) were Enterococcus faecium, 15 (23%) were Enterococcus faecalis, and 6 (10%) were other Enterococcus species. Fourteen among the E. faecalis isolates show resistance to Ertapenem-EDTA, while 17 (44.8%) of the E. faecium show resistance to Ertapenem-EDTA to presumptively reveal their NDM-1 phenotype. The PCR detection of the NDM-1 gene further confirmed 23 (36.5%) isolates as positive genotypes amongst the isolates that previously showed presumptive NDM-1 phenotype. It was also observed that 10 (15.9%) of Enterococcus faecium members harbored the NDM-1 genotype, whereas 8 (12.7%) members of the Enterococcus faecalis harbored the NDM-1 genotype. The observation of such resistance determinants necessitates a call for the adroit application of relevant therapeutics in the management of related infections and an environmental health caution to prevent the spread of such resistance potential enteric bacteria pathogens.

Epidemiologic potentials and correlational analysis of Vibrio species and virulence toxins from water sources in greater Bushenyi districts, Uganda

Adequate water supply is one of the public health issues among the population living in low-income settings. Vibriosis remain a significant health challenge drawing the attention of both healthcare planners and researchers in South West districts of Uganda. Intending to clamp down the disease cases in the safest water deprive locality, we investigated the virulent toxins as contaminants and epidemiologic potentials of Vibrio species recovered from surface waters in greater Bushenyi districts, Uganda. Surface water sources within 46 villages located in the study districts were obtained between June and October 2018. Standard microbiological and molecular methods were used to analyse samples. Our results showed that 981 presumptive isolates retrieved cell counts of 10–100 CFU/g, with, with (640) 65% confirmed as Vibrio genus using polymerase chain reaction, which is distributed as follows; V. vulnificus 46/640 (7.2%), V. fluvialis 30/594 (5.1), V. parahaemolyticus 21/564 (3.7), V. cholera 5/543 (0.9), V. alginolyticus 62/538 (11.5) and V. mimicus 20/476 (4.2). The virulence toxins observed were heat-stable enterotoxin (stn) 46 (82.10%), V. vulnificus virulence gene (vcgCPI) 40 (87.00%), extracellular haemolysin gene {vfh 21 (70.00)} and Heme utilization protein gene {hupO 5 (16.70)}. The cluster analysis depicts hupO (4.46% n = 112); vfh (18.75%, n = 112); vcgCPI and stn (35.71%, & 41.07%, n = 112). The principal component analysis revealed the toxins (hupO, vfh) were correlated with the isolate recovered from Bohole water (BW) source, while (vcgCPI, stn) toxins are correlated with natural raw water (NRW) and open springs (OS) water sources isolates. Such observation indicates that surface waters sources are highly contaminated with an odds ratio of 1.00, 95% CI (70.48–90.5), attributed risk of (aR = 64.29) and relative risk of (RR = 73.91). In addition, it also implies that the surface waters sources have > 1 risk of contamination with vfh and > six times of contamination with hupO (aR = 40, − 66). This is a call of utmost importance to the population, which depends on these water sources to undertake appropriate sanitation, personal hygienic practices and potential measures that ensure water quality.

Occurrence of Multiple, Extensive and Pan Drug-Resistant Pseudomonas aeruginosa and Carbapenemase Production from Presumptive Isolates Stored in a Biobank at Ethiopian Public Health Institute.

PurposePseudomonas aeruginosa is a common cause of nosocomial infections with associated morbidity and mortality because the organism is unresponsive to commonly available antimicrobials. This study was undertaken to determine the multiple drug-resistant (MDR), extensive drug-resistant (XDR) and pan drug-resistant (PDR) phenotype of P. aeruginosa and its carbapenemase production rate from presumptive isolates stored in the biobank at the Ethiopian Public Health Institute (EPHI).MethodsA cross-sectional study was conducted at the EPHI laboratory, Addis Ababa, Ethiopia from March to June 2021. Stored isolates of Pseudomonas spp. which had been characterized by manual identification methods were further processed for species-level identification (ID) and antimicrobial susceptibility testing (AST) using a Becton Dickinson (BD) Phoenix automated system. The isolates were analyzed for carbapenemase enzyme production using the modified Carbapenem Inactivation Method (mCIM). The data analysis was done using SPSS version 20 software.ResultsIn this study, 110 presumptive Pseudomonas isolates from a biobank were re-analyzed, 100 of them were found to be Pseudomonas and among these P. aeruginosa accounted for 98% and P. putida accounted for 2%. The majority of isolates were recovered from wound (46%) specimens followed by ear swabs (18%). The highest level of resistance was observed against ceftazidime (35%) and the lowest level of resistance was observed against amikacin (2%). Twenty-seven isolates were identified as candidates for carbapenemase enzyme production testing, of which only 3/27 (11%) isolates were detected as carbapenemase enzyme producers.ConclusionThis study shows an increasing rate of MDR and XDR isolates and the appearance of PDR in P. aeruginosa strains; this is a serious problem in Ethiopia. The lack of newer anti-pseudomonal antibiotics adds to the problem. In order to alleviate this, infection prevention activities should be promoted, and treatment of bacterial infections should be guided by antibiotic susceptibility test results.

Human-Associated Methicillin-Resistant Staphylococcus aureus Clonal Complex 80 Isolated from Cattle and Aquatic Environments.

Background: Human-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) has mainly been reported in South African pig and chicken farms. The prevalence of antibiotic-resistant genes (ARGs), virulence factors (VFs), and multilocus sequence types (MLSTs) associated with HA-MRSA in cattle farms has not been reported. Consequently, this study characterised LA-MRSA and its spread from cattle farms into the environment. Method: Husbandry soil (HS), nearby river water (NRW), animal manure (AM) and animal drinking water (ADW) were collected on and around a cattle farm. Presumptive MRSA isolates were identified from these samples using CHROMagar media and genotyped as MRSA sequence types (STs), selected ARGs, and VFs, using polymerase chain reaction. An MLST-based dendrogram was generated to link the farm MRSA strains with those in a nearby river. Results: The prevalence of MRSA was 30.61% for HS, 28.57% for ADW, 22.44% for NRW, and 10.20% for AM. Isolates from HS harboured the highest number of resistant genes, with 100% for mecA, 91.66% for ermA, and 58.33% for blaZ. However, no ermC or tetM genes were detected. MRSA isolates from AM harboured the lowest number of resistant genes. Only sec and seq enterotoxins were found in all the assessed MRSA isolates. MRSA from the farm revealed six STs (ST80, ST728, ST1931, ST2030, ST3247, and ST5440); all of STs belonged to clonal complex 80 (CC80). An MLST-based dendrogram based on the concatenated sequences of MLST genes under the maximum likelihood criterion revealed four clades of amalgamated MRSA isolates from various livestock environmental matrices, including the NRW. Conclusion: The results suggest that livestock environmental matrices might be reservoirs of MRSA that could subsequently disseminate through runoff to pollute water resources. Therefore, continued surveillance of HA-MRSA in livestock environments is warranted.

Molecular characterization and antibiotic resistance of Vibrio parahaemolyticus from Indian oyster and their probable implication in food chain.

Vibrio parahaemolyticus is one of the leading causes of diarrhoea and gastroenteritis in human on consumption of raw or insufficiently cooked seafood. This study was aimed at isolating and characterizing the pathogenic and pandemic V. parahaemolyticus from oysters (n = 90) in coastal parts of West Bengal, India; their antibiotic resistance and potential for involvement in the food chain. During bacteriological culture, typical V. parahaemolyticus colony was recovered in 88.9% samples followed by presumptive identification in 71 (78.9%) samples by characteristic biochemical (K/A) test. All the presumptive isolates (n = 71) were confirmed by species specific Vp-toxR PCR assay. Of these, 10 (14.08%) were tdh+ and none for the trh. Further, 5 (50%) of these tdh+ isolates were found to carry the pandemic potential gene in PGS-PCR assay; however, none in GS-PCR. Majority (80%) of these pathogenic (tdh+) isolates belonged to pandemic serovars (OUT: KUT; OUT: K24; O1: KUT; O1:K25; O10: KUT) and only 20% to non-pandemic serovars (OUT: K15; O9:K17). All the isolates (100%) exhibited resistance to cefpodoxime followed by ampicillin and cefotaxime (90%), ceftizoxime (60%), tetracycline (50%), ceftriaxone (40%), ciprofloxacin and nalidixic acid (10% each). Overall, the study findings suggested that 11.1% (10/90) of commonly marketed oysters in this area were harbouring pathogenic V. parahaemolyticus. Moreover, 5.5% (5/90) of the oyster population were harbouring pandemic strains of this pathogen. Besides, the pathogenic isolates from oysters were exhibiting a considerable genetic relatedness (53 to 70%) to human clinical isolates in PFGE analysis that relates to a substantial public health risk. Further, their multidrug resistance added gravity to the antimicrobial resistance (AMR), a globally growing public health threat and this is a critical area of concern especially during the treatment of foodborne gastroenteritis.

Research Note: Prevalence and molecular characteristics of Clostridium perfringens in “no antibiotics ever” broiler farms

Clostridium perfringens (C. perfringens) is the etiological agent of necrotic enteritis and gangrenous dermatitis; 2 diseases that cause significant economic and welfare concerns to the broiler industry. Previously, Clostridium-related diseases were managed with the use of antimicrobial growth promoters fed to broilers that improved gut health and performance. The recent shift to no antibiotics ever (NAE) production has increased the incidence of Clostridium-related diseases. The objective of this study was to identify C. perfringens prevalence and toxinotypes in NAE farms. Samples of litter, feces, and cloacal swabs were collected from 4 NAE broiler farms in the summer of 2019, on d 28 and d 56 of one flock cycle. A total of 734 presumptive isolates were obtained from 192 samples collected in the study. Irrespective of the age of flock and sample type, all 192 samples contained at least one colony presumptively identified as C. perfringens on Perfringens agar plate with morphology as a single, round colony with opaque ring and black center. All isolates were further screened using PCR for confirmation, toxinotyping, and identification of virulence-associated genes. Only 9 isolates among the 734 presumptive isolates were confirmed as C. perfringens and all confirmed isolates were toxinotype A with variation in presence of netB, cpb2, and tpeL. More extensive studies are required to assess the prevalence and virulence of C. perfringens in NAE farms.

Prevalence and Antimicrobial Resistance Profile of Listeria monocytogenes from Retailed Fresh Cat Fish and Frozen Fish in Abuja, Nigeria.

This study investigated the prevalence and antibiotic resistance profile of Listeria monocytogenes from fresh catfish (Clarias species) and frozen raw fish (Mackerel and Herring). A total of 180 samples which comprised 60 units of fresh catfish, mackerel, and herring frozen fish each distributed uniformly across three locations in Abuja, were randomly collected within a period of three months. The samples were analyzed using standard bacteriological methods at the Animal science/bacteriology laboratory, Faculty of Agriculture, University of Abuja. Presumptive isolates were further serotyped using latex agglutination and subjected to antimicrobial sensitivity testing at the Advance Biotechnology laboratory (SHESTCO) Sheda, Abuja. Overall prevalence of L. monocytogenes in this study was 10.6% (n=19/180) distributed across Gwagwalada (20%), Bwari (11.7%) and none in Kwali Area council. The occurrence according to fish types showed 18.3% in mackerel, 10.0% in herring fish while 3.33% was from catfish. There was no statistically significant difference (p>0.05) between the prevalence of Listeria monocytogenes in the fish type studied. Antimicrobial resistance profile indicated high MAR index (≥ 0.4) which revealed a diverse spread of bacterial resistance to antibiotics within the fish population in the study area. This was characterized by 100% resistance of L. monocytogenes isolates to ampicillin and tetracycline while few (5) isolates were susceptible to chloramphenicol (71.5%), streptomycin (61.2%). This finding provides a baseline information on the prevalence and antibiotic profile of L. monocytogenes in catfish and frozen fish in Abuja, Nigeria. Proper hygienic handling of fish during processing and sales is optimum in mitigating the risk of foodborne illness due to L. monocytogenes. Adequate control of antimicrobial agent usage is also recommended to reduce the occurrence and spread of potential multidrug resistance strains.

Nasal Colonization and Antibiotic Resistance of Staphylococcus Species Isolated from Healthy Veterinary Personnel at Veterinary Medical Care Facilities in Tripoli

Background/Aim: Veterinary medical personnel may carry important antibiotic-resistant organisms playing important role in their dissemination and emergence. The purpose of the study was to investigate nasal colonization and antibiotic resistance of Staphylococcus species isolated from veterinary personnel (VP). Methods: A total of 47 VP were sampled, whereby nasal samples were subjected to selective and typical laboratory protocols. Presumptive isolates were further confirmed and fully characterized by the Phoenix automated microbiological system then further tested by polymase chain reactions for mecA and panton-valentine leukocidin (pvl) genes. Results: A total of 34 (72%) VP were colonized with various species, mostly coagulase-negative staphylococci. A collection of 34 staphylococci isolates were collected of which 21% and 6% were, respectively, positive for mecA and pvl genes expressed exclusively by Staphylococcus aureus and S. epidermidis. Conclusion: VP may carry various staphylococci species of public health importance expressing multidrug resistant and virulent traits. Preventative measures and continuous monitoring are required to control the spread of methicillin-resistant staphylococci in veterinary clinics.

First Report of Multi-drug Resistant Staphylococcus haemolyticus in Nosocomial Infections in North Western Saudi Arabia

We report in this study for the first time the prevalence of multiple resistant Staphylococcus haemolyticus in clinical settings in Saudi Arabia. A total of 1060 clinical specimens of hospitalized patients were screened for the presence of S. haemolyticus in the period between September and December 2020. Primary identification of the isolates was carried out by colonial characteristics on mannitol salt agar and clumping factor test, confirmation of presumptive isolates and antimicrobial susceptibility testing was performed by Vitek® 2, while PCR was employed to detect mecA and vanA genes. A total of 20 S. haemolyticus isolates were recovered from 20 samples (blood cultures, urine, nasal swab, wound swab, groin swab, and axilla swab), 90% (P <0.001, x2) of the isolates were multiple resistant to three antimicrobial agents and more. Resistance to oxacillin was exhibited in 95% of the isolates, while none of the isolates were resistant to vancomycin and linezolid, yet resistance to rifampicin was observed in 30 % of the isolates. The findings of this study highlights the emerging trends of Staphylococcus haemolyticus as potential drug resistant pathogen in hospital settings in Saudi Arabia, which requires in depth investigation on molecular understanding on antimicrobial resistance and virulence traits of the strains.

Isolation and Identification of Nonstarter Lactic Acid Bacteria from Traditional Baramily Cheese

Nonstarter lactic acid bacteria (NSLAB) have an important role in quality and safety of traditional Baramily cheese (Domiati cheese related type). Therefore, the objective of this study was to isolate and identify NSLAB with potential technological features from traditional Baramily cheese. Thirty-three samples of Baramily cheese randomly collected from retails in Cairo metropolitan area. The samples were characterized by physiochemical, textural profile and microbiological analysis. Ninety presumptive NSLAB (30 Lactobacillus spp . and 35 Enterococcus spp .) strains were isolated on MRS and Kenner-Faecal (KF) Streptococci media; and were characterized for growth temperature, salt tolerance and milk coagulation. All presumptive NSLAB isolates were tolerant to 6.5 % NaCl. Of them, 40 isolates were tolerant to 10.0 % NaCl including 16 presumptive Lactobacillus spp ., and 24 presumptive Enterococcus spp . isolates based on the results, 11 representative isolates with potential technological features were selected for genetic identification using 16S rRNA technique, then were confirmed for growth and acidity development in skim milk within 48 h, and were tested for antimicrobial activity against some food spoilage and pathogenic microorganisms. The eleven isolates were identified as Ent. durans (1), Ent. faecalis (5), Lb. paraplantarum (1), Lb. plantarum (3), and Lb. rhamnosus (1). All isolated strains were confirmed active in skim milk, and some exhibited antimicrobial activity against tested food spoilage and pathogenic microorganisms. Both Lb. rhamnosus and Lb. plantarum were confirmed as the isolates with high activity in milk. Ent. durans and Ent. faecalis exhibited antimicrobial activity against Enterobacer aerogenes and E. coli. However, Lb. plantarum exhibited antimicrobial activity against both Enterobacer aerogenes, E. coli and Ps. aeruginosa. Listeria. monocytogenes, S. typhimurium, and Campylobacter. jejuni showed significant resistance to all tested NSLAB isolates. They can be concluded that the identified NSLAB isolated can be used to standardized and improve the quality and safety of Baramily cheese and other types related to Domiati cheese

Microbiological and Metagenomic Characterization of a Retail Delicatessen Galotyri-Like Fresh Acid-Curd Cheese Product

This study evaluated the microbial quality, safety, and ecology of a retail delicatessen Galotyri-like fresh acid-curd cheese traditionally produced by mixing fresh natural Greek yogurt with ‘Myzithrenio’, a naturally fermented and ripened whey cheese variety. Five retail cheese batches (mean pH 4.1) were analyzed for total and selective microbial counts, and 150 presumptive isolates of lactic acid bacteria (LAB) were characterized biochemically. Additionally, the most and the least diversified batches were subjected to a culture-independent 16S rRNA gene sequencing analysis. LAB prevailed in all cheeses followed by yeasts. Enterobacteria, pseudomonads, and staphylococci were present as <100 viable cells/g of cheese. The yogurt starters Streptococcus thermophilus and Lactobacillus delbrueckii were the most abundant LAB isolates, followed by nonstarter strains of Lactiplantibacillus, Lacticaseibacillus, Enterococcus faecium, E. faecalis, and Leuconostoc mesenteroides, whose isolation frequency was batch-dependent. Lactococcus lactis isolates were sporadic, except for one cheese batch. However, Lactococcus lactis, Enterobacteriaceae, Vibrionaceae, Salinivibrio, and Shewanellaceae were detected at fairly high relative abundances culture-independently, despite the fact that their viable counts in the cheeses were low or undetectable. Metagenomics confirmed the prevalence of S. thermophilus and Lb. delbrueckii. Overall, this delicatessen Galotyri-like cheese product was shown to be a rich pool of indigenous nonstarter LAB strains, which deserve further biotechnological investigation.

Existence of Multiple ESBL Genes among Phenotypically Confirmed ESBL Producing Klebsiella pneumoniae and Escherichia coli Concurrently Isolated from Clinical, Colonization and Contamination Samples from Neonatal Units at Bugando Medical Center, Mwanza, Tanzania.

The proportions and similarities of extended-spectrum β-lactamase (ESBL) producing K. pneumoniae (ESBL-KP) and E. coli (ESBL-EC) carrying multiple ESBL genes is poorly known at our setting. This study investigated the existence of multiple ESBL genes (blaCTX-M, blaTEM, and blaSHV) among ESBL-KP and ESBL-EC concurrently isolated from clinical, colonization, and contamination samples from neonatology units in Mwanza-Tanzania. Twenty and 55 presumptive ESBL-EC and ESBL-KP, respectively, from a previous study archived at −80 °C were successfully recovered for this study. Isolates were screened and confirmed for production of ESBLs by phenotypic methods followed by multiplex PCR assay to determine ESBL genes. All (100%) and 97.3% of presumptive ESBL isolates were phenotypically confirmed by Clinical and Laboratory Standards Institute (CLSI) and modified double-disc synergy methods, respectively. About 93.3% (70/75) of phenotypically confirmed ESBL isolates had at least one ESBL gene, whereby for 62.9% (44/70), all ESBL genes (blaCTX-M, blaTEM, and blaSHV) were detected. Eight pairs of ESBL bacteria show similar patterns of antibiotics susceptibility and ESBL genes. ESBL-KP and ESBL-EC, concurrently isolated from clinical, colonization and contamination samples, harbored multiple ESBL genes. Further, eight pairs of ESBL isolates had similar patterns of antibiotics susceptibility and ESBL genes, suggesting transmission of and/or sharing of mobile genetic elements (MGEs) among ESBL-KP and ESBL-EC.

English

BACKGROUND Conjunctivitis is one of the most common nontraumatic eye complaints and is one of the most frequently reported diseases in the outpatient and emergency departments. Bacterial conjunctivitis has been reported as one of the most common type of infectious conjunctivitis after viral infections. It is also considered as the primary cause of acute conjunctivitis in children. This study was conducted to isolate and identify organisms causing bacterial conjunctivitis and to determine their in vitro susceptibility or resistance. METHODS This descriptive study was conducted in the Departments of Ophthalmology and Microbiology at Katihar Medical College from December 2018 to May 2020. Sociodemographic and clinical data were collected from 175 patients using structured questionnaire. External ocular specimens were collected using sterile swabs and inoculated on blood agar, MacConkey’s agar and chocolate agar. Presumptive isolates were further identified by a series of biochemical tests. All isolated organisms were tested for their in vitro antimicrobial susceptibility against various antibiotics using the Kirby-Baur disk diffusion method. RESULTS A total of 175 samples were collected, out of which, 62.8 % (110 / 175) showed growth of bacteria. Maximum cases of bacterial conjunctivitis were seen in the age group 11 - 20 years. The male to female ratio was 2.7:1. Maximum frequency of bacterial conjunctivitis was observed from May to September. Staphylococcus aureus was the most common bacteria isolate 65.5 % (72 / 110) followed by Staphylococcus epidermidis 19.1 % (21 / 110). Most of the Staphylococcus aureus isolates were found to be sensitive to moxifloxacin 98.6 % (71 / 72) and gentamicin 95.8 % (69 / 72). 25 % (18 / 72) of Staphylococcus aureus strains were found to be resistant to cefoxitin and were considered as methicillin-resistant Staphylococcus aureus (MRSA) strains. Maximum numbers of gram-negative strains were sensitive to moxifloxacin 100.0 % (9 / 9) followed by tobramycin 88.9 % (8 / 9). Pseudomonas aeruginosa strains showed maximum sensitivity to moxifloxacin 100.0 (8 / 8) followed by ofloxacin and ciprofloxacin 62.5 % (5 / 8). CONCLUSIONS This study provides an insight into the organisms isolated from cases of bacterial conjunctivitis in Katihar District of Bihar. Determining the susceptibility pattern of these pathogens to available antibiotics is crucial for effective management of bacterial conjunctivitis especially when treatment has to be given empirically. KEY WORDS Bacterial Conjunctivitis, Antibiogram