Enterococcus Sp Research Articles

A Novel Enterococcus-Based Nanofertilizer Promotes Seedling Growth and Vigor in Wheat (Triticum aestivum L.).

Excessive use of chemical fertilizers poses significant environmental and health concerns. Microbial-based biofertilizers are increasingly being promoted as safe alternatives. However, they have limitations such as gaining farmers' trust, the need for technical expertise, and the variable performance of microbes in the field. The development of nanobiofertilizers as agro-stimulants and agro-protective agents for climate-smart and sustainable agriculture could overcome these limitations. In the present study, auxin-producing Enterococcus sp. SR9, based on its plant growth-promoting traits, was selected for the microbe-assisted synthesis of silver nanoparticles (AgNPs). These microbial-nanoparticles SR9AgNPs were characterized using UV/Vis spectrophotometry, scanning electron microscopy, and a size analyzer. To test the efficacy of SR9AgNPs compared to treatment with the SR9 isolate alone, the germination rates of cucumber (Cucumis sativus), tomato (Solanum lycopersicum), and wheat (Triticum aestivum L.) seeds were analyzed. The data revealed that seeds simultaneously treated with SR9AgNPs and SR9 showed better germination rates than untreated control plants. In the case of vigor, wheat showed the most positive response to the nanoparticle treatment, with a higher vigor index than the other crops analyzed. The toxicity assessment of SR9AgNPs demonstrated no apparent toxicity at a concentration of 100 ppm, resulting in the highest germination and biomass gain in wheat seedlings. This work represents the first step in the characterization of microbial-assisted SR9AgNPs and encourages future studies to extend these conclusions to other relevant crops under field conditions.

Biosynthesis of gold nanoparticles from Martynia annua aqueous leaves extract, its antioxidant potential and antimicrobial ability against selected wound pathogens

The field of nanotechnology has great potential within the realm of modern nanoscience and technology. Ecologically responsible nanoparticle production requires the careful selection of a solvent that is ecologically acceptable, together with the use of reducing and stabilizing chemicals that are also environmentally beneficial. The utilization of gold nanoparticles has been widely investigated in the fields of separation sciences and illness diagnosis for biological purposes. The objective of this study is to synthesize gold nanoparticles utilizing a Water-based Leaf Extract from the Martynia annua Plant in an ecologically sustainable manner. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were employed to analyze the morphological characteristics, stability, and crystalline structure of the produced nanoparticles. The experimental results validate the commencement of the gold ion reduction process by the detected change in color of the reaction mixture to a deep purple colour. Moreover, the synthesis was confirmed by the use of UV–visible spectrometry, within the wavelength region of 584 nm. The zeta potential of the produced nanoparticles is reported to be −31 mV, while the average diameter of the particles is about 21 nm. The synthesized particles exhibit significant antioxidant capacity in comparison to the standard. Further AuNPs shows strong antibacterial potential against Escherichia coli, Staphylococcus aureus, Streptococcus sp, Bacillus subtilis, and Enterococcus sp was 53.94 µg/mL, 78.02 µg/mL, 55.47 µg/mL, 55.83 µg/mL, and 95.24 µg/mL respectively Synthesized particles demonstrate substantial cytotoxicity against A549 human lung cancer cells and it shows the inhibitory concentration at 20 µg/ml. The results indicated a significant decrease in cell viability, which was directly linearly related to the dosage of particles. The Martynia annua plant mediated gold nanoparticles exhibit potent antioxidant and antibacterial properties effectively combating specific wound infections.

PCR identification of Enterococcus Species as a Primary Pathogen in Neonatal Bloodstream Infections at Damascus University Paediatric Hospital

Bacterial septicaemia is one of the most common causes of death in newborns throughout the globe. Recently, gram positive bacteria have been detected as a main responsible of hospital acquired blood infection in developed country especially Enterococcus sp. and Staphylococcus sp. This preliminary study aimed to identify Enterococcus species and Staphylococcus species isolated form acquired blood infection in the department of premature and neonates at paediatric university hospital in Damascus, based on PCR technology. the antibiotic sensitivity these pathogens was also investigated against common antibiotics usually used to treat septicaemia in this hospital. Bacterial gDNA was extracted directly from blood samples of children with acquired Septicemia. The bacterial infection was confirmed in 50 samples based on the amplification of 16srDNA gene. Genus Enterococcus sp. and Staphylococcus species were identified as source of infection in samples using specific primers via PCR technique. The antibiotic sensitivity of isolated bacterial strains was studied using Kirby-Bauer disc method. Our study showed that 47 of the 50 samples of the infection were bacterial. The rate of blood infection caused by Enterococcus species was 24%, and 4% for Staphylococcus sp. the isolated bacteria showed a high sensitivity to Amikacin, medium sensitivity to Vancomycin, and less sensitivity to Ampicillin and Gentamycin. Enterococcus species Showed good sensitivity to Amikacin and Vancomycin and low sensitivity to Gentamycin, while was resistant to Ampicillin. Furthermore, the two isolated stains Enterococcus sp and Staphylococcus species showed a good sensitivity against chlorhexidine. This study confirmed the importance of molecular technologies in diagnosing the acquired septicaemia and identifying the specific infectious agent. The molecular test showed that Enterococcus sp. was an important cause of acquired blood infection in neonates respect to ampicillin resistant staphylococcus species.

Microbiota diversity of three Brazilian native fishes during ice and frozen storage

This study aimed to assess the bacterial microbiota involved in the spoilage of pacu (Piaractus mesopotamics), patinga (female Piaractus mesopotamics x male Piaractus brachypomus), and tambacu (female Colossoma macropomum × male Piaractus mesopotamics) during ice and frozen storage. Changes in the microbiota of three fish species (N = 22) during storage were studied through 16S rRNA amplicon-based sequencing and correlated with volatile organic compounds (VOCs) and metabolites assessed by nuclear magnetic resonance (NMR). Storage conditions (time and temperature) affected the microbiota diversity in all fish samples. Fish microbiota comprised mainly of Pseudomonas sp., Brochothrix sp., Acinetobacter sp., Bacillus sp., Lactiplantibacillus sp., Kocuria sp., and Enterococcus sp. The relative abundance of Kocuria, P. fragi, L. plantarum, Enterococcus, and Acinetobacter was positively correlated with the metabolic pathways of ether lipid metabolism while B. thermosphacta and P. fragi were correlated with metabolic pathways involved in amino acid metabolism. P. fragi was the most prevalent spoilage bacteria in both storage conditions (ice and frozen), followed by B. thermosphacta. Moreover, the relative abundance of identified Bacillus strains in fish samples stored in ice was positively correlated with the production of VOCs (1-hexanol, nonanal, octenol, and 2-ethyl-1-hexanol) associated with off-flavors. 1H NMR analysis confirmed that amino acids, acetic acid, and ATP degradation products increase over (ice) storage, and therefore considered chemical spoilage index of fish fillets.

Long-lasting effects of control measures on trends in incidence in neonatal late-onset sepsis due to multiresistant bacteria in a Brazilian neonatal unit

In response to a 1995 outbreak of sepsis caused by multidrug-resistant (MR) Gram-negative bacteria (GNB), a Brazilian level III neonatal unit established a series of control and prevention measures. This study evaluated the long-term effects of these measures on late-onset neonatal sepsis (LONS) caused by MR bacteria from 2000 to 2020 and examined their impact on in-hospital mortality. Newborns with LONS and positive cultures for Staphylococcus aureus, GNB, and Enterococcus sp were selected, adhering to Center for Desease Control and Prevention and local criteria. Joinpoint regression analysis was used to assess annual trends. Over the 21-year period, the overall LONS rate was 4.6%, showing a significant decline from 2000 to 2016 (P < .0001, slope -0.36). However, from 2016 to 2020, there was a non-significant increase in sepsis rates (slope +0.92, P = .08). MR sepsis were in 15.8% of sepsis cases and displayed a non-significant upward trend (slope +0.50, P = .08) with no major shifts. In-hospital mortality rates for MR and non-MR LONS showed no significant differences (P = .413). The study indicates a low prevalence of MR sepsis due to effective antimicrobial use and educational interventions. MR sepsis prevalence remained low and stable, not increasing in-hospital mortality.

Phenomics and genomic features of Enterococcus avium IRMC1622a isolated from a clinical sample of hospitalized patient

BackgroundEnterococcus avium (E. avium) is a Gram-positive nosocomial pathogen that is commonly isolated from the alimentary tract. The objective of this functional genomics study was to identify the resistant genes by analyzing the genome of E. avium IRMC1622a, a type of bacteria found in feces collected from a patient at a Saudi Arabian tertiary hospital. MethodsThe bacterial strain IRMC1622a was identified by 16 S rRNA sequencing as Enterococcus sp. The resistance phenomics were performed using VITEK® 2, and morphological analysis was achieved using a scanning electron microscope (SEM). Finally, the whole bacterial genome of the bacterial strain IRMC1622a was subjected to sequencing during October 2023 using Oxford Nanopore long-read sequencing technology, and mining for resistant genes. ResultsThe results of antimicrobial resistant phenomics indicated that the IRMC1622a strain was sensitive to all tested antimicrobial agents except for erythromycin, and the same result was confirmed by genomic analysis in addition to other classes of antibiotics. SEM showed E. avium IRMC1622a is ovoid shape, in single cells (L 1.2797 ± 0.1490 µm), in pairs (L 1.7333 ± 0.1054 µm), and in chains (L 2.44033 ± 0.1978 µm). The E. avium IRMC1622a genome has 14 (in CARD) antimicrobial resistance genes that were identified with several mechanisms of antimicrobial resistance, such as the efflux pump and conferring antibiotic resistance. The present study revealed that the E. avium IRMC1622a genome contains a high number of genes associated with virulence factors, and 14 matched pathogenic protein families and predicted as human pathogen (probability score 0.855). We report two (ISEnfa4 and ISEfa5) mobile genetic elements for the first time in the E. avium genome. ConclusionsThe study concludes that E. avium IRMC1622a is susceptible to all tested antibacterials except erythromycin. The IRMC1622a has 14 genes encoding antimicrobial resistance mechanisms, including the efflux pump and conferring antibiotic resistance. This could indicate a potential rise in E. avium resistance in healthcare facilities. These observations may raise concerns regarding E. avium resistance in healthcare. We need more research to understand the pathophysiology of E. avium, which leads to hospital-acquired infections.

Private and well drinking water are reservoirs for antimicrobial resistant bacteria

Water quality testing does not recognise antimicrobial resistance (AMR) and is often limited to indicators of faecal contamination Escherichia coli and Enterococcus species. In Europe, data on AMR in drinking water is scarce. In Ireland, as in many countries, household drinking water is supplied via mains or via private wells or water schemes. Using citizen science, we identified Irish private drinking water supplies as reservoirs of antimicrobial resistant bacteria (ARB). Gram-negative (n = 464) and Gram-positive (n = 72) bacteria were isolated. We identified instances of potentially opportunistic ARB such as Enterobacter cloacae, Acinetobacter baumannii and Enterococcus species. We report reservoirs of multidrug resistance in Enterococcus casseliflavus, E. cloacae, E. coli, Stenotrophomonas maltophilia, and Serratia rubidaea. We also identified linezolid-resistant Enterococcus in Irish drinking water. Linezolid is a last-resort antibiotic used to treat vancomycin-resistant Enterococcus sp. Additionally, we identified mobile AMR in three water samples, two of which were carried on IncF group, one on IncQ and five on Col-like plasmids. Our work suggests that private drinking water is a potential sink and source of AMR pathogens. This highlights a value of drinking water surveillance in a One Health framework as the surveillance would provide information regarding the movement and persistence of ARB and ARGs that are able to survive in drinking water and subsequently have the opportunity to be mobilised through humans; linking the environment to the human and potentially threatening human health.

Refining Bacteriuria as a Risk Factor for Complications After Urethroplasty: Identifying the Culprit

To determine which bacteria are associated with an increased risk of 90-day complications after urethroplasty. Preoperative bacteriuria is associated with an increased risk of complications after urethroplasty. However, it remains unclear which specific micro-organisms are the primary drivers of this morbidity. A single-institution, 2-surgeon retrospective review was performed on patients undergoing urethroplasty from 08/2003 to 06/2021. Preoperative bacteriuria was considered significant when the patient had a mixed culture with ≥108 CFU/L or an identifiable micro-organism with ≥106 CFU/L. Descriptive statistics were used to summarize the results and chi-square was used to determine the association between 90-day complications (Clavien ≥2) and clinical characteristics/bacteria. Out of 1611 patients, 23.2% (373) had significant preoperative bacteriuria. The most common pathogens included coagulase-negative staphylococcus 18.5% (69), mixed growth 15.8% (59), Escherichia coli 10.7% (40), and Enterococcus 14.2% (53). 7.9% (128/1611) experienced a significant 90-day complication (Clavien-Dindo ≥2). Gram-negative bacilli including E coli, Pseudomonas sp, Klebsiella sp, Serratia sp, Citrobacter sp, Achromobacter sp, Stenotrophomonas sp, and Morganella sp were associated with higher rates of postoperative complications (14.2%; P=.01) as well as Enterococcus sp (15.1%; P=.03). However, gram-positive cocci (7.9%; P=.97), gram-positive bacilli (11.8%; P=.47), mixed growth (5.1%; P=.54) and Candida (16.7%; P=.27) were not. Neither escalating concentrations of bacteria (P=.44) or number of strains (P=.08) were associated with increased risk of complications. The main driver of bacteriuria-related complications after urethroplasty are gram-negative bacilli and Enterococcus sp. Patients with bacteriuria related to other micro-organisms can likely proceed with urethroplasty without increased risk of postoperative complications.

Enterococcus montenegrensis sp. nov., isolated from artisanal Montenegrin dry sausage.

A novel, Gram-positive, facultative anaerobe, coccoid and non-motile bacterium, designated as CoE-012-22T was isolated from dried beef sausage (the original name in Montenegro is Govedji Kulen) manufactured in the municipality of Rozaje (Montenegro) in 2021. Cells of this strain were oxidase- and catalase-negative. Growth occurred at 4-50 °C, at pH 5.0-8.0 and with 0-6.5 % (w/v) NaCl in diverse growth media. MALDI-TOF analysis identified the strain as Enterococcus canintestini (log score 2). Phylogenetic analysis of the 16S rRNA gene and whole genome sequences assigned the strain to the genus Enterococcus. The closest relatives were E. canintestini DSM 21207T and E. dispar ATCC 51266T with 16S rRNA gene sequence pairwise similarities of 99.34 and 98.59 %, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between isolate CoE-012-22T and other enterococci species were below the thresholds for species delineation thresholds (95.0 % ANI; 70.0 % dDDH) with maximum identities of 84.13 % (ANIb), 86.43 % (ANIm) and 28.4 % (dDDH) to E. saigonensis JCM 31193T and 70.97 % (ANIb), 88.99 % (ANIm) and 32.4 % (dDDH) to E. malodoratus ATCC 43197T. Two unknown Enterococcus isolates, Enterococcus sp. MJM12 and Enterococcus SMC-9, showed identities of 99.87 and 99.94 % (16S rRNA), 98.57 and 98.65 % (ANIb), 98.93 and 99.02 % (ANIm), and 89.8 and 90.0 % (dDDH) to strain CoE-012-22T and can therefore be regarded as the same species. Based on the characterization results, strain CoE-012-22T was considered to represent a novel species, for which the name Enterococcus montenegrensis sp. nov. is proposed. The type strain is CoE-012-22T (=DSM 115843T=NCIMB 15468T).

Modeling TiO2/UV–vis bacterial inactivation: Useful tools for reactor optimization and design

Heterogeneous photocatalysis applying TiO2 based catalysts has been widely studied for removing inorganic and organic compounds from water and for bacterial inactivation. This available and low-cost catalyst has demonstrated to be effective in the removal of organic pollutants and inactivation of pathogenic bacteria from water. The design of proper types of industrial-scale photoreactors has not been yet successfully implemented, probably due to the conceptual complexity of modeling this process in real wastewater. As a result, TiO2 based photocatalysis is still considered an effective but energetic-inefficient process. In this work, Escherichia coli (gram-positive) and Enterococcus sp (gram-negative) were selected for studying the kinetics of TiO2 photocatalysis. Since several approaches, such as fist-order kinetics, are not truly representative of the bacterial inactivation process, the experimental data were fitted to different mathematical models, such as Gompertz model, which has demonstrated to describe the process properly. Moreover, the effect of the main variables of the process in the inactivation kinetic constant of the Gompertz model has ben studied. More precisely, light intensity, water matrix, catalyst concentration and bacteria have been under study and their effect has been included in the kinetic equation. Finally, operational and construction parameters of a 20 m3/d annular photoreactor for bacterial inactivation has been successfully optimized applying the proposed kinetic model.

Evaluación de la actividad antimicrobiana de la bebida de kéfir contra escherichia coli, salmonella typhimurium y shigella flexneri

Objective: Evaluate the antimicrobial activity of the Kefir drink against Escherichia coli, Salmonella typhimurium and Shigella flexneri Method: The Kefir used in the investigation was acquired in Toluca, State of Mexico. We performed a reactivation of Kefir with pasteurized milk and analyzed 3 carbohydrates (honey, sugar and piloncillo) at different concentrations and times, 80, 100, 120% and 24, 48 and 72 hours respectively. Isolated cultivable microorganisms were characterized by phenotypic, biochemical and mass spectroscopy techniques. The initial and final pH were determined during the study time. The antimicrobial activity was carried out by extracting the metabolites present in the ferment with the Kirby-Bauer method, in addition the direct ferment was evaluated, to determine if there was inhibition with the Escherichia coli (ATCC 11229) strains, Salmonella typhimurium (ATCC 14028) and Shigella flexneri (ATCC 12022). Results: It was observed that in the three carbohydrates used at a concentration of 120% and at a time of 72 h, a lower pH was obtained (3.51 to 3.64) compared to their initial concentration (6.50 to 6.64). From the metabolites extracted in the different ferments, no inhibition halo was obtained with the strains analyzed. However, when using direct ferments, it was observed that in the carbohydrates used (sugar, honey, piloncillo) there was the presence of an inhibiting halo or the growth of colonies other than those evaluated. The isolated cultivable microorganisms were: Pichia kudriavzevii (yeast); Enterococcus sp (gram-positive coconut) and Lactobacillus sp (gram-positive bacillus). Conclusions : Kefir ferments made with different carbohydrates, came to present a degree of inhibition only as a consortium against Gram-negative microorganisms analyzed. Keywords: Kefir; fermentation microbiota; infection; antimicrobial activity

Use of Common Herbs to Control Microbial Aerosols in Toilet Rooms

Four distinct plant species were used in an investigation into the capacity of plant active volatile essence to eradicate microorganisms in the atmosphere (bioaerosols) in restrooms: Allium sativum (garlic), Allium cepa (onion), Zingiber officinalis (ginger), and Ocimum gratissimum (scent leaf). The study was conducted in the student restrooms for microbiology at Rivers State University Nkpolu Oroworukwu in Port Harcourt. Sedimentation method of aerosol sampling was used to collect the air samples. Artificial culture media were exposed to air at different times, including nutrient agar for total heterotrophic bacteria, Mac Conkey agar for enteric bacteria, sadour and dextrose agar for aerobic fungi, thiosulfate citrate bile salt sucrose agar for vibrio, Cystine lactose electrolyte deficient agar for urinary pathogens, and mannitol salt agar for staphylococcus.&#x0D; Samples was taken from the toilet without any mashed plant and served as a control. The THB isolates identified were Bacillus spp, Pseudomonas sp, Staphylococcus sp, Lactobacillus sp, Enterococcus sp, Corynobacterium sp, Escherichia coli, Klebsiella pneumonia. While the fungi isolated were Aspergillus niger, pennicillum sp, Rhizopus sp, Saccharomyces sp, Mucor Sp, Candida sp, Asperillus flavus, Fusarium sp. It can be deduced that these medicinal herbs has the ability in reducing microbial aerosol using ginger, onion, scent leaf, garlic also by combination of the herbs which are Onion &amp; garlic, Onion &amp; garlic, Onion &amp; ginger, Garlic &amp; scent leaf, Garlic &amp; ginger, Scent leaf &amp; ginger, Onion, garlic &amp; scent leaf, Onion, garlic &amp; ginger, Garlic, Scent leaf &amp; ginger, Onion, garlic, scent leaf &amp; ginger. Specifically the microbial aerosols in this investigation including bacteria and fungi were Bacillus species, Pseudomonas species, Staphylococcus species, Lactobacillus species, Enterococcus species, Corynobacterium, Escherichia coli, Klebsiella pneumonia. Aspergillus niger, pennicillum species, Rhizopus species, Saccharomyces species, Mucors species, Candida species, Asperillus flavus, Fusarium species. This work proved that microbial load can be reduced using natural means (plant extract).

Assessment of the bacteriological qualities of meat and contact surfaces in markets in Abia State, Nigeria

Background: Microbial contamination of meat comes from external sources during cutting, handling, and processing of the meat. This study was carried out to assess the bacteriological qualities of meat and contact surfaces in markets in Abia State, Nigeria. Methods: This research involved the use of a Hazard Analysis Critical Control Point (HACCP) checklist to investigate the sanitation and hygiene practices of meat sellers and a laboratory study of red and white meat, water, and meat-contact surface samples. A total of 425 meat samples collected from 425 meat sellers from some randomly selected markets in Abia State were used for the study. There were also 20 water samples, 22 samples from table surfaces, 22 samples from knife surfaces, and 14 samples from transport vehicles. The multistage simple random sampling technique through balloting was employed to determine communities/markets for the study. Samples for the study were collected and analyzed using standard microbiological techniques such as culturing and the bacteria were enumerated and identified using biochemical and chemical tests. Results: The prevalent bacterial isolates include Staphylococcus sp (78.80%), Bacillus sp (73.17%), Enterococcus sp (64.00%), Escherichia coli (62.11%), Salmonella sp (62.11%), Klebsiella sp (51.29%), Micrococcus sp (44.94%) and Campylobacter sp (43.52%). SPSS analysis using the one-way ANOVA showed no significant difference (p &gt; 0.05) in bacteria isolated from markets in the three Senatorial Zones of the State. Staphylococcus sp was isolated in 61.11% of the tables, 50.00% of vehicles, 41.67% of knives and 46.32% of water; Salmonella sp was isolated in 47.22% of the tables, 36.11% of vehicles, 30.56% of knives and 43.85% of water; Bacillus sp was isolated in 41.67% of the tables, 44.44% of vehicles, 33.33% of knives and 23.70% of water; Campylobacter sp was isolated in 27.78% of the tables, 25.00% of vehicles, 30.56% of knives and none in water. There was no significant difference (p &gt; 0.05) in bacteria isolated from the contact surfaces and water from the markets in the three zones of the State. Conclusion: The bacteriological quality of meat in markets in Abia State could be said to be poor due to the isolation of Indicator bacteria such as E, coli, Salmonella, and Campylobacter from the studied meat samples. The presence of E. coli in the studied meat samples is an indicator of feacal contamination and a red alert for the Public health sector. It is recommended that meat sellers undergo proper training and regularly update their knowledge of meat safety.

PDMS-PIM45 prevents encrustation and prevents/impedes colonization of uropathogens

Catheters are the most widely used medical device and on the same note, catheter associated infections are also prevalent in health and medical care, globally. Among them, urinary catheters associated infections (CAUTI) pre-dominates the nosocomial infections. Antimicrobial/antifouling catheter innovations to overcome infections has escalated exponentially in recent years. Imidazolium-based polymer antimicrobial (PIM45) is a potent broad-spectrum antimicrobial and incorporation of PIM45 in PDMS matrix (PDMS-PIM45 biomaterial) proved to produce a robust, long-lasting antimicrobial biomaterial and could be recycled up to 45 days. Thus, exhibiting beneficial potential for development of medical devices that display inherent antimicrobial propensity. In this study, using a continuous flow model of artificial urine, we proved that PDMS-PIM45 could eradicate the CAUTI causative pathogens, Escherichia coli, Klebsiella pneumoniae, Vancomycin-Resistant Enterococcus sp, completely at 106 CFU/ml loading. Though colonization was not inhibited, lower rate of infection and absence of biofilm development was observed for Methicillin-Resistant Staphylococcus aureus, a newly emerging CAUTI pathogen. Importantly, we have also shown that PDMS-PIM45 could prevent encrustation following Proteus mirabilis infection, and maintain the low pH of artificial urine over 7 days in continuous flow model.

Isolation and identification of proteolytic lactic acid bacteria from freshwater pomfret (Colossoma macropomum) intestine

The production of freshwater pomfret (Colossoma macropomum) in Indonesia is abundant, but the digestive tract waste weighing 10-15% of the fish body is not widely utilized. The fish's digestive tract can potentially produce lactic acid bacteria (LAB). Lactic acid bacteria have a proteolytic system that can produce extracellular protease enzymes. Protease enzymes are the most widely utilized enzymes in various industries and have a global revenue of up to $2.1 billion in 2021. Protease enzymes derived from microbes are in great demand due to the efficiency of time, place, cost, and better cultivation techniques than animal and plant sources. This study aimed to isolate and identify proteolytic lactic acid bacteria from the intestines of freshwater pomfret fish and determine their proteolytic index. The methods used were morphological, biochemical, sugar, and proteolytic tests. The BAT-A isolate with the highest proteolytic index of 2.52 with characteristics of Gram-positive, non-spore, facultatively anaerobic, catalase-negative, non-motile, homofermentative, can ferment glucose, maltose, lactose and sucrose which were then identified as proteolytic lactic acid bacteria Enterococcus sp which has the potential as a candidate source of protease enzymes from bacteria isolated from the intestines of freshwater pomfret.

Abstract 20 Long-Term Follow-Up of Cryopreserved Umbilical Cord Tissue as a Source of Mesenchymal Stem Cells

Abstract Introduction Mesenchymal stem cells (MSCs) can differentiate into various cell types and exhibit immunomodulatory and paracrine effects. The cryopreservation of umbilical cord tissue as a viable source of MSCs has great potential for the field of regenerative medicine. We previously demonstrated that it is feasible to cryopreserve umbilical cord tissue cut into small fragments measuring 2 to 5 mm in length and obtain viable cells by thawing them between 30 and 60 days after freezing. Objectives We aim to assess the condition of previously frozen samples for periods exceeding one year and analyze the data obtained from the cryopreservation of new samples. Methods A total of 834 new samples were frozen with our protocol for umbilical cord tissue cryopreservation. These Samples were thawed after obtaining microbiological contamination results of each sample. Additionally, a group of 100 samples that have been kept frozen for at least one year were selected to be thawed to assess the viability of the tissue frozen for extended periods of time. All cultures were maintained and the days to reach confluence were registered. Results The microbial analysis of the group of 834 new samples showed similar microbial profile and risk factors to those previously reported by us, with higher contamination frequencies associated with vaginal delivery and samples obtained by less experienced personnel in the operating room. Moreover, similar to our previous reports, the most frequent microorganism detected in contaminated samples were Staphylococcus sp, Escherichia Coli, Enterococcus sp and Streptocuccus sp. The group of 100 samples that were kept frozen for a minimum period of one year were thawed to assess if we could obtain viable cells from them. All cell cultures obtained from the thawed tissue were successful, reaching confluence between days 18 and 23, which is consistent with our previously observed timings. Discussion New cryopreserved tissue samples, and samples frozen for more than one year had viable cells that can be expanded as a source of MSCs. Microbial profile of those samples showed association with sample collection conditions at the operating room indicating that proper training of the personnel is the key to reduce contamination rates.

Assessment of microbial flora, characterization and public health implications of two species of smoked fish sold in ‘Otuocha’ Market in Anambra State

Microbiological assessment of fresh and smoked Synodontis schall and Oreochromis niloticus fish species was conducted. Three replicates of fresh and smoked fish samples were aseptically obtained from fishermen and open market in Otuocha area of Anambra State, Nigeria. The culture from organs of fresh fish and smoked samples were inoculated on Nutrient agar (NA.), Salmonella Shigella Agar (SSA), MacConkey Agar (MCA) and Potato Dextrose Agar respectively for heterotrophic bacteria and fungi counts. Colonial and microscopic characterizations of the isolates from the cultured media were examined. There no growth of coliform and Salmonella sp from tissue of the fresh fish and the smoked fish samples. Total plate counts of bacteria and fungi from gills, intestine and skin were found above 1 x 106 cfu/g safety limit recommended for foods. Bacteria count ranged from 1.27 x 107 cfu/g to 2.95 x 107 cfu/g and 1.0 x 106 cfu/g to 2.88 x 108 cfu/g for fungi. Six genera of bacteria namely Salmonella sp, Escherichia coli, Staphylococcus sp, Enterococcus sp, Bacillus sp and Pseudomonas sp were suspected from fish samples. Four fungi genera: Saccharomyces sp, Penicillium sp, Rhizopus sp and Mucor sp were indicated in this work. This assessment has revealed the level of gross contamination of fresh fish and safety of smoked fish samples from foodborne microorganisms.

Effect of probiotics on hematological parameters of male and female Wistar rats

In the present study, the effect of probiotics on the hematology of Wistar rats was examined. Locally isolated Lactobacillus plantarum MZ707748 (Pro 1), L. plantarum MZ710117 (Pro 2), Weisella confusa MZ727611 (Pro 3), and L. plantarum MZ735961 (Pro 4) were used. One strain of probiotic, L. acidophilus-14 (Pro 5), was purchased commercially. Different groups were designed as G1, G2, G3, G4, and 5, G5/PC consisting only pro 5 and NC & 0 day were untreated. Different groups have different probiotics like G1 containing Pro 1 and Pro 2, G2 comprising Pro 3 and Pro 4, G3 containing Pro 2, Pro 3 and Pro 5, G4 having Pro 1–5, and G5 containing Pro 5. A complete count of blood, serum chemistry, fecal analysis, and histopathological examination of the thymus and liver were done. Statistical differences were seen in the complete blood count parameters (p < 0.05). No difference was observed in AST, ALT, bilirubin, albumin, IL-6, and IgA (p > 0.05) except for TP, creatinine, and globulin (p < 0.05). Fecal strains of probiotic groups were antibiotic-resistant. In males, Lactobacillus helveticus OQ152020, Enterococcus lactis OQ1519891, E. faecium OQ152017, L. gasseri OQ152017, and E. lactis OQ152019 were isolated from positive control, G1, G2, G3, and G4 respectively. In females, Enterococcus sp. OP800231, Limosilactobacillus fermentum OQ151985, E. lactis OP800267, L. plantarum OP800244, and E. faecium OQ151988 were isolated from positive control, G1, G2, G3 and G4, respectively. It was concluded that all probiotic strains were safe to use and had beneficial effects on the hematology of Wistar rats.

Antibacterial activity of exopolysaccharide produced by bee gut-resident Enterococcus sp. BE11 against marine fish pathogens

BackgroundIn recent years, the demand for innovative antimicrobial agents has grown, considering the growing problem of antibiotic resistance in aquaculture. Adult Apis mellifera honeybees’ gut represents an outstanding habitat to isolate novel lactic acid bacteria (LAB) able to produce prominent antimicrobial agents.MethodsIn the current study, twelve LAB were isolated and purified from the gut of adult Apis mellifera. The isolates were screened for exopolysaccharide (EPS) production. The most promising isolate BE11 was identified biochemically and molecularly using 16 S rRNA gene sequence analysis as Enterococcus sp. BE11 was used for the mass production of EPS. The partially purified BE11-EPS features were disclosed by its physicochemical characterization. Moreover, the antimicrobial activity of BE11 cell free supernatant (CFS) and its EPS was investigated against some fish pathogens namely, Pseudomonas fluorescens, Streptococcus agalactiae, Aeromonas hydrophila, Vibrio sp. and Staphylococcus epidermidis using well-cut diffusion method.ResultsThe physicochemical characterization of BE11-EPS revealed that the total carbohydrate content was estimated to be ~ 87%. FTIR and NMR analysis ascertained the presence of galactose and glucose residues in the EPS backbone. Moreover, the GC-MS analysis verified the heterogeneous nature of the produced BE11-EPS made up of different monosaccharide moieties: galactose, rhamnose, glucose, arabinose sugar derivatives, and glucuronic acid. BE11 CFS and its EPS showed promising antimicrobial activity against tested pathogens as the inhibition zone diameters (cm) ranged from 1.3 to 1.7 and 1.2–1.8, respectively.ConclusionThe bee gut-resident Enterococcus sp. BE11, CFS, and EPS were found to be promising antimicrobial agents against fish pathogens and biofilm producers affecting aquaculture. To the best of our knowledge, this is the first study to purify and make a chemical profile of an EPS produced by a member of the bee gut microbiota as a potential inhibitor for fish pathogens.

Novel combination of nanoparticles and metallo-β-lactamase inhibitor/antimicrobial-based formulation to combat antibiotic resistant Enterococcus sp. and Pseudomonas sp. strains

Nanotechnology presents an innovative strategy to combat the spread of antibiotic resistant bacteria and their resistance genes throughout different ecosystems. To address this challenge, nanoparticles (silver, gold, zinc and copper) alone or in combination with metallo-β-lactamase inhibitor/antimicrobial-based formulation (EDTA/HLE) showed antimicrobial activity against antibiotic resistant Enterococcus sp. and Pseudomonas sp. strains. Furthermore, the observed synergistic effect was detected notably for silver, zinc or copper nanoparticles with EDTA (ethylenediaminetetraacetic acid) and silver nanoparticles with HLE against planktonic Enterococcus sp. strains, or gold nanoparticles+EDTA or HLE against Pseudomonas sp. Regarding activity against bacterial biofilms, zinc nanoparticles combined with either of the reagents caused strong inhibition of developing biofilms of antibiotic resistant Enterococcus sp. Pseudomonas sp. strains, while preformed biofilms were mainly inhibited by silver nanoparticles+reagent. Microscopic analyses confirmed that the antimicrobial activity of nanoparticles was caused by adsorption to the bacterial cell surface, and further enhanced by chelating agents. Hence, we can conclude that nanoparticles+EDTA or HLE could represent a good alternative to limit the spread of antibiotic resistant bacteria in the food chain and the environment.