Bacterial Culture Research Articles

Optimization of the production of Exopolysaccharide (EPS) from biofilm-forming bacterial consortium using different parameters

Bacterial cells produce a variety of exopolysaccharide (EPS) throughout their life cycle. EPS plays a crucial role in the formation of biofilms and the control of environmental processes in microbial communities. The bacterial community benefits from biofilms in several ways, including nutrient compartmentation and storage, environmental stress resistance and synergism. The generation of EPS by consortium-associated bacteria, which involves a variety of microorganisms, is versatile and efficient for use in industrial and environmental processes, such as biotechnology and pollution degradation. The qualitative and quantitative chemical characteristics of the consortium's EPS are mostly determined by the type of culture utilized, nutrient type, temperature, and pH. The main goal of the study was to find out how EPS biosynthesis works in a bacterial consortium culture. To achieve maximum EPS regeneration, pH, temperature, carbon, and nitrogen sources were optimized. A consortium of three bacterial strains i.e. Klebsiella pneumonia strain, Pseudomonas aeruginosa strain and Burkholderia cepacian strain that were distinguished by their capacity to produce biofilms were developed as part of the study. The maximum total EPS production was detected after 8 days of incubation at pH 7.5 (15.5g/L) and a temperature of 35 °C (12.60g/L). The optimum EPS production was identified as 17.84g/L and 21.07g/L when ammonium sulfate and glucose were employed as nitrogen and carbon supplements, respectively. The protein concentration of the EPS was 3067µg/mL, which was more than the carbohydrate (263.10µg/mL) and DNA (7.60µg/mL) content. The total protein/carbohydrate ratio of the EPS detected in the present study was 11.65, which was much higher than in prior investigations. FTIR analysis of EPS confirmed the functional groups of carbohydrates, proteins, lipids and DNA, viz., C=O, COOH, NH, OH, CH and OCH3. The study's findings revealed that enhancing the consortium's EPS molecules involves lowering biofilm-related infections and improving the efficacy of antimicrobial treatments in wastewater.

Sexual activity, vaginal symptoms, maternal perineal hygiene behavior, and constipation on ano-vaginal colonization of group B streptococcus in near term pregnancy

BackgroundMaternal Group B Streptococcus (GBS) colonization is influenced by many factors but results are inconsistent. Consideration of antenatal risk factors may help inform decision making on GBS microbiological culture screening where universal screening is not standard of care. We sought to identify independent predictors of GBS colonization at 34–37 weeks gestation incorporating vaginal symptoms, perineal hygiene measures, sexual activity, and a potential novel factor, constipation.MethodsIn this prospective cross-sectional study, 573 women at 34–37 weeks gestation had an ano-vaginal swab taken and sent for selective culture for GBS. Women were asked about vaginal bleeding, discharge, irritation and candidiasis, antibiotic use during pregnancy, ano-vaginal hygiene practices such as douching and perineal cleansing after toileting, sexual intercourse related activities, and a potential novel factor for GBS carriage, constipation. Maternal basic demographics and obstetric-related characteristics were also collected. Bivariate analyses were performed to identify associates of GBS colonization. All variables with p < 0.05 found on bivariate analysis were then included into a model for multivariable binary logistic regression analysis to identify independent risk factors for GBS colonization.ResultsGBS colonization was found in 235/573 (41.0%) of participants. Twenty six independent variables were considered for bivariate analysis. Eight were found to have p < 0.05. Following adjusted analysis, six independent predictors of GBS colonization were identified: ethnicity, previous neonatal GBS prophylaxis, antenatal vaginal irritation, antibiotic use, recent panty liner use, and frequency of sexual intercourse. Vaginal discharge and perineal cleansing were not associated after adjustment. Recent douching and constipation were not associated on bivariate analysis.ConclusionThe identification of independent predictors of GBS colonization in late pregnancy may inform the woman and care provider in their shared decision making for microbiological screening at 35–38 weeks gestation in locations where universal GBS screening is not standard of care.Ethics oversightThis study was approved by the Medical Ethics Committee of University Malaya Medical Centre (UMMC) on August 9, 2022, reference number 2022328-11120.

Use of diagnostic tests in elderly patients consulting the emergency department. Analysis of the emergency department and elder needs cohort (EDEN-8)

ObjectiveAnalyse the association between the use of diagnostic tests and the characteristics of older patients 65 years of age or more who consult the emergency department (ED). MethodsWe performed an analysis of the EDEN cohort that includes patients who consulted 52 Spanish EDs. The association of age, sex, and ageing characteristics with the use of diagnostic tests (blood tests, electrocardiogram (ECG), microbiological cultures, X-ray, computed tomography, ultrasound, invasive techniques) was studied. The association was analysed by calculating the adjusted odds ratios (aOR) and their 95 % confidence intervals (CI) using a logistic regression model. ResultsA total of 25,557 patients were analysed. There was an increase in the use of diagnostic tests based on age, with an aOR for blood test of 1.805 (95 %CI 1.671 – 1.950), ECG 1.793 (95 %CI 1.664 – 1.932) and X-ray 1.707 (95 %CI 1.583 – 1.840) in the group of 85 years or more. The use of diagnostic tests is lower in the female population. Most ageing characteristics (cognitive impairment, previous falls, polypharmacy, dependence, and comorbidity) were independently associated with increased use of diagnostic tests. ConclusionsAge, and the characteristics of ageing itself are generally associated with a greater use of diagnostic tests in the ED.

Limosilactobacillus reuteri and Its Probiotic Potential against Cariogenic Bacteria

Bacteriotherapy is a promising option in addressing dental caries, a persistent global public health challenge with multifactorial origin, including dysbiosis. Despite the exploration of various probiotics, outcomes remain inconclusive. Objective: This study aimed to assess the inhibitory potential of L. reuteri and other potential probiotics like S. salivarius and S. oralis on the growth, adhesion, colonization, and viability of major cariogenic pathogens, comparing their probiotic efficacy. Methods: An in vitro experimental study was conducted, encompassing direct competition assays in solid and liquid co-culture tests and the characterization of adhesion to dental enamel and cell viability by life or death assay. Results: L. reuteri exhibited the significant inhibition of S. sobrinus and S. mutans growth in both solid and liquid cultures, with statistically notable differences. Scanning electron microscopy and confocal microscopy demonstrated reduced cariogenic biofilm formation when combined with L. reuteri, corroborated by diminished bacterial viability and decreased dental enamel coverage. These findings underscore L. reuteri’s potential as an effective agent in caries prevention. Conclusion: The study suggests L. reuteri could serve as an effective probiotic in bacteriotherapy against dental caries. It displayed substantial inhibitory activity in vitro against cariogenic bacteria, impeding biofilm formation and adhesion, thereby impacting cell viability.

Chromosome-Scale Genome Assembly Provides Insights into Fresh Pine Wood Decay Strategies of the Wolfiporia hoelen

The sclerotia of Wolfiporia hoelen (Fr.) Y.C. Dai &amp; V. Papp is an important traditional Chinese medicine with diverse pharmacological properties. This study utilized a combination of PacBio Long-Read Sequencing, Illumina Short-Read Sequencing, and Hi-C Sequencing to generate a high-quality chromosome-level genome assembly of a W. hoelen strain Minling A5. There were 112 contigs in the genome, with 62.95 Mb in total length and 4.21 Mb in length for the contig N50. The average GC content was 51.89%. Based on Hi-C data, we corrected the CCS data and scaffolded them into 14 pseudo-chromosomes. The genome contained 44.37% repetitive sequences and 12,670 protein-coding genes, 86.53% (10,963) of which could be functionally annotated in at least one of the KOG, GO, Pfam, Swissprot, TrEMBL, NR, and KEGG databases. In addition, 240 transfer RNAs, 97 ribosomal RNAs, and 103 other non-coding RNAs were identified in the W. hoelen genome. A total of 755 pseudogenes were also identified, with an average length of 2665.51 bp. Further, there were 398, 100, 2837, 519, and 2068 genes annotated by CAZymes, TCDB, PHI, P450, and DFVF databases, respectively. One notable attribute of W. hoelen is its capacity to thrive in a substrate of fresh pine sawdust. Through an analysis of the growth on various pure wood sawdust culture media, we found that the growth of W. hoelen and Sparassis latifolia on pine sawdust was similar to that on broad-leaved wood sawdust, while the growth of Pleurotus ostreatus, P. eryngii, and Cyclocybe aegerita was slower than that on broad-leaved wood sawdust. By the functional annotation analysis of orthogroups in these five mushroom-forming fungi, it was determined that 645 orthogroups were specifically common in W. hoelen and S. latifolia. The genes in these specific orthogroups were significantly enriched in 12 pathways, including steroid biosynthesis, biosynthesis of antibiotics, and tyrosine metabolism. The high-quality genome and comparative genome analysis results significantly contribute to advancing our foundational knowledge of W. hoelen biology, while also offering valuable insights for the development of innovative biotechnological approaches aimed at enhancing the efficient and sustainable utilization of Pinus.

Скрининг и характеристика антиоксидантных свойств психрофильных микроводорослей и цианобактерий Балтийского моря

At present, the issue of obtaining a complex of biologically active substances with antioxidant activity from psychrophilic Psychrophilic microalgae and cyanobacteria are a prospective source of biologically active antioxidant substances. New antioxidant complexes could expand the scope of their industrial application. The research objective was to identify psychrophilic microalgae and cyanobacteria from the Baltic Sea in order to study their antioxidant properties. The research featured psychrophilic microalgae and cyanobacteria obtained from the Curonian Lagoon and the Baltic Bay in the Baltic Sea, Kaliningrad Region, Russia, in March – May 2022. The authors used the Pasteur method and the flow cytometry method to isolate pure cultures of psychrophilic microalgae and cyanobacteria. The method of spectrophotometry made it possible to study the antioxidant activity by analyzing radical scavenging, reducing ability, and chelating. The psychrophilic microalga Skeletonema pseudocostatum demonstrated the highest antioxidant activity in all three methods: 17.62 μmol/g trolox equivalents according to the ABTS method, 58.16 μmol/g trolox equivalents according to the DPPH method, and 3.91 μmol/g trolox equivalents according to the FRAP method. The psychrophilic microalga Thalassiosira pseudonana exhibited the following values of antioxidant activity: 12.08, 12.42, and 3.13 μmol/g trolox equivalents, respectively. The antioxidant activity of the psychrophilic microalgae Fragilariopsis kerguelensis was 13.53, 11.84, and 1.09 μmol/g trolox equivalents, respectively. The antioxidant activity of the psychrophilic cyanobacterium Aphanizomenon gracile was 15.73, 19.89, and 2.47 μmol/g trolox equivalents, respectively. The antioxidant activity of the psychrophilic cyanobacterium Anabaena cylindrica was 12.62, 13.16, and 2.16 μmol/g trolox equivalents, respectively. The samples of psychrophilic microalgae and cyanobacteria obtained from natural environment in the Russian Baltic Sea demonstrated good antioxidant properties, which makes them a potential raw material for new pharmaceutical substances.

Ancillary Benefit of Microbiology Culture Diagnostic Stewardship: Decreasing Healthcare’s Climate Impact

Abstract We calculated weights of blood, urine, and endotracheal tube culture supplies and quantified greenhouse gas emissions emitted for disposal of these supplies. Of note, disposal related emissions for a positive blood and endotracheal tube culture are each equivalent to driving 0.6 and 0.4 miles, respectively, in a gasoline-powered vehicle.

Cross-sectional study investigating the components and quality of colostrum and colostrum replacement products fed to Ontario dairy goat kids

Colostrum replacement products for use in goat kids are sourced from bovine colostrum and often used by producers to supplement or replace maternal colostrum to prevent infections. To compare the colostrum replacement products fed on-farm to caprine colostrum a cross-sectional study was undertaken. Ontario dairy goat producers were asked to collect first milking colostrum from their goats and samples of the reconstituted commercial replacement product currently in use. The frozen samples were thawed and submitted for testing of fat, protein and lactose content, IgG1 concentration and aerobic bacterial culture. Compared with caprine colostrum, the reconstituted replacement products were lower in protein (11.7%; P = 0.0007), and fat (4.6%; P < 0.0001) and higher in lactose (5.4%; P < 0.0001) on average. The average IgG1 concentration in goat colostrum (53.5 g/L; range: 16.6-1985.8) was significantly higher than in colostrum replacement products (33.7 g/L; range: 10.7-55.3) (P < 0.0001). The Brix cut-point for good quality goat colostrum (50 g/L) was calculated at 23% (sensitivity = 69.6%, specificity = 88.0%) for goat colostrum and 26% for the colostrum replacement product (sensitivity = 87.5%, specificity = 100%). The average aerobic count for goat colostrum was lower (2.95 log10 cfu/mL) than the colostrum replacement product samples that were cultured (3.85 log10 cfu/mL; P < 0.0001). Further investigation into colostrum replacement products, including on-farm storage of opened powdered product and mixing and storage of reconstituted product, is warranted. Variability in the levels of IgG1, aerobic bacterial growth and fat, protein and lactose content in colostrum replacement products also requires further exploration to determine their effects on kid health.

Polymeric nanocarrier-based adjuvants to enhance a locally produced mucosal coryza vaccine in chicken

Infectious coryza (IC) is an acute upper respiratory disease of chicken caused by Avibacterium (A.) paragallinarum. This disease results in an increased culling rate in meat chicken and a marked decrease in egg production (10% to more than 40%) in laying and breeding hens. Vaccines were first used against IC and effectively controlled the disease. Nanotechnology provides an excellent way to develop a new generation of vaccines. NPs have been widely used in vaccine design as adjuvants and antigen delivery vehicles and as antibacterial agents; thus, they can be used as inactivators for bacterial culture. In this research, the antibacterial effects of several nanoparticles (NPs), such as silicon dioxide with chitosan (SiO2-CS), oleoyl-chitosan (O.CS), silicon dioxide (SiO2), and iron oxide (Fe3O4), on A. paragallinarum were studied. Additionally, different A. paragallinarum vaccines were made using the same nanomaterials at a concentration of 400 µg/ml to help control infectious coryza disease in chicken. A concentration of 400 µg/ml of all the NPs tested was the best concentration for the inactivation of A. paragallinarum. Additionally, this study showed that the infectious coryza vaccine adjuvanted with SiO2 NPs had the highest immune response, followed by the infectious coryza vaccine adjuvanted with Fe3O4 NPs, the infectious coryza vaccine adjuvanted with SiO2-CS NPs, and the infectious coryza vaccine adjuvanted with O.CS NPs in comparison with the infectious coryza vaccine adjuvanted with liquid paraffin (a commercial vaccine).

Total Synthesis and Biological Profiling of Putative (±)-Marinoaziridine B and (±)-N-Methyl Marinoaziridine A

The total synthesis of two new marine natural products, (±)-marinoaziridine B 7 and (±)-N-methyl marinoaziridine A 8, was accomplished. The (±)-marinoaziridine 7 was prepared in a six-step linear sequence with a 2% overall yield. The key steps in our strategy were the preparation of the chiral epoxide (±)-5 using the Johnson Corey Chaykovsky reaction, followed by the ring-opening reaction and the Staudinger reaction. The N,N-dimethylation of compound (±)-7 gives (±)-N-methyl marinoaziridine A 8. The NMR spectra of synthetized (±)-marinoaziridine B 7 and isolated natural product did not match. The compounds are biologically characterized using relevant in silico, in vitro and in vivo methods. In silico ADMET and bioactivity profiling predicted toxic and neuromodulatory effects. In vitro screening by MTT assay on three cell lines (MCF-7, H-460, HEK293T) showed that both compounds exhibited moderate to strong antiproliferative and cytotoxic effects. Antimicrobial tests on bacterial cultures of Escherichia coli and Staphylococcus aureus demonstrated the dose-dependent inhibition of the growth of both bacteria. In vivo toxicological tests were performed on zebrafish Danio rerio and showed a significant reduction of zebrafish mortality due to N-methylation in (±)-8.

A Survey of the Prevalence of Infections Present among Inpatients in a Tertiary Care Hospital in 2023

Objective: To explore the current infection rate among inpatients in a tertiary hospital in 2023, to understand the infection situation in the hospital, and to provide a reliable basis for carrying out further hospital infection prevention and control and other work. Methods: Inpatients of a tertiary hospital on a certain date in 2023 were selected, and the survey data were extracted with the Apricot Grove real-time monitoring system using a combination of questionnaires and medical record data. Results: The infection rate was 12.63%, of which the hospital infection rate was 2.25% and the community infection rate was 10.38%. Lower respiratory tract infections accounted for 77.28% of the community infections, and lower respiratory tract infections accounted for 73.44% of the cases of hospital infections, with a total of 44 strains of pathogens isolated from hospital infections, and a total of 218 strains of pathogens isolated from community infections. The total application rate of antimicrobial drugs was 31.67%, the proportion of prophylactic drugs in the whole hospital was 9.66%, the proportion of therapeutic drugs was 90.33%, and the rate of bacterial culture delivery was 39.18%. Conclusion: The infection rate survey truly reflects the dynamics of infection in this hospital, makes clearer the key departments and key links of hospital infection prevention and control, further provides the basis for targeted infection control, and improves the knowledge and execution of hospital infection prevention and control by medical staff.

Detection of volatile organic compounds as new paradigm to accelerate antimicrobial susceptibility testing: performance evaluation of VITEK® REVEAL™.

The measurement of VOCs release in the headspace of a bacterial culture represents a new approach to rapidly assess antimicrobial susceptibility. Herein, we evaluated the diagnostic performance of the VITEK® REVEAL™ system directly from a collection of Gram-negative positive blood cultures. One hundred and twenty-eight positive blood cultures were included in the analysis (Enterobacterales, n = 95; Pseudomonas aeruginosa, n = 21; Acinetobacter baumannii complex, n = 12). Samples were processed using VITEK® REVEAL™ according to the manufacturer's recommendations, and MICs of 22 antimicrobials were compared with those obtained using reference methods. Categorical agreement (CA), essential agreement (EA) and categorical errors were calculated. Overall, 2220 strain/antibiotic pair combinations were analysed. Of these, most were classified as resistant by reference antimicrobial susceptibility testing (1091/2220; 48.7%). The overall CA and EA were 97.6% and 97.7%, respectively. CA ranged from 97.5% in Enterobacterales to 97.9% in both P. aeruginosa and A. baumannii complex. The overall number of categorical discrepancies were: 18 very major errors (1.6%), 13 major errors (1.2%) and 22 minor errors (2.4%). EA ranged from 95.2% in P. aeruginosa to 98.1% in Enterobacterales. Screening test for ESBL phenotype was positive, indeterminate and negative in 13.7%, 32.6% and 27.4% of Enterobacterales isolates tested by both VITEK® REVEAL™ and the reference method, showing 100% CA. VITEK® REVEAL™ represents a reliable tool to obtain antimicrobial susceptibility results of the main Gram-negative species directly from positive blood cultures with time to results of less than 8 h.

Gyrfalcon Disease Ecology: A Survey Across Western Alaska

ABSTRACT The Gyrfalcon (Falco rusticolus) is a top avian predator, an Arctic specialist, and among the bird species most vulnerable to climate change. This vulnerability is driven by their narrow ecological niche, limited or lack of southward migration, and circumpolar distribution where the most rapid climatic changes are occurring. Climatic and habitat changes may alter Gyrfalcon disease ecology due to changes in vector distributions, host ranges, and pathogen life cycles. Warmer Arctic temperatures and accompanying landscape changes may also alter the Gyrfalcon’s prey base, and dietary habits can influence transmission of pathogens. To better understand disease ecology in Gyrfalcons, we compared pathogen prevalence across varying time periods at three study sites in Alaska—the Seward Peninsula (2014–2022), the Alaska Peninsula (2021–2022), and the Yukon–Kuskokwim Delta (2008–2013). We collected Gyrfalcon whole blood, thin blood films, cloacal swabs, and fecal samples for serology, haemoparasite assays, microbiological cultures, and fecal tests for parasites. An aliquot of whole blood preserved on filter paper or in Longmire solution was kept for molecular diagnosis of haemoparasites. Serology revealed high exposure to Salmonella (77%), low seroprevalence of avian influenza antibodies (1.5%), exposure to falcon adenovirus type 1 in hatch-year Gyrfalcons (1.3%), and the first report of a Leucocytozoon spp. blood parasite in a Gyrfalcon. We found no antibodies indicative of prior exposure to avian paramyxovirus, West Nile virus, or Chlamydia. One nestling and one hatch-year bird sampled (2 of 12) on the Seward Peninsula exhibited oral plaques from capillarids (Eucoelus spp.) in contrast to those trapped in the Izembek National Wildlife Refuge on the Alaska Peninsula (0 of 6).

Use of non-&lt;i&gt;Saccharomyces&lt;/i&gt; yeasts in the &lt;i&gt;pris de mousse&lt;/i&gt; of Lambrusco. Microbial evolution through alcoholic fermentation and effect on wine volatile profile

Lambrusco is a sparkling wine largely produced in the north of Italy, especially in the Emilia region. The possible application of two non-Saccharomyces yeasts in the secondary bottle fermentation (Champenoise method) was tested in combination with a commercial strain of S. cerevisiae to obtain wines having a distinctive volatile profile. Our results demonstrated that the gradual increase of ethanol content in the pied de cuve ensured the adaptation of Hanseniaspora guilliermondii and Torulaspora delbrueckii at the bottle fermentation, with survival comparable with that of S. cerevisiae, in the order of 6 log units. The simultaneous presence of two yeast species reduced the maximum fermentation rate, without any relevant alteration in the main oenological parameters of resultant wines. GC MS-MS analysis of the volatile profile of wines (46 compounds) highlighted differences in wine made from a pure culture of S. cerevisiae from wines obtained by mixed yeasts. Acetates, esters, and fatty acids are the classes of volatile compounds mostly affected by using different yeasts in the bottle fermentation of Lambrusco wines. This work provided for the first time information about the volatile profile of Lambrusco and suggests an innovative application of non-Saccharomyces yeast in the production of sparkling wines by champenoise methods.

EFFECT OF NITRATE-REDUCING BACTERIA AND CELERY ROOT (APIUM GRAVEOLENS VAR. RAPACEUM) ON THE SENSORY PROPERTIES OF DRIED MEAT “BILTONG”

The objective of our study was to assess the effect of nitrate-reducing bacteria and natural nitrate source on the sensory properties of dried meat biltong. Appearance, colour on the cut, aroma, taste and juiciness, acidity, sweetness, and consistency were evaluated. The members of the panel gave their ratings between 1 and 5 according to the characteristics of the samples, with 1 being the lowest rating and 5 being the best rating. In the sensory evaluation of dried meat samples without oxygen absorber packaging, the group (P2) with bacterial culture, celery powder, and NaCl showed the highest scores for appearance, taste, juiciness, acidity, and consistency. Notably, P3 samples had significantly lower consistency scores compared to P2. Additionally, sample P1, with bacterial culture and NaCl, improved the colour on the cut compared to the negative control (C) with only NaCl. The best aroma and sweetness results were in the P3 group with curing salt, although these differences were not statistically significant (P ≥ 0.05). The sensory evaluation of dried meat samples packaged with an oxygen absorber revealed that the combination of bacterial culture, celery powder, and NaCl (AP2) had the most positive influence on appearance, colour on the cut, and consistency. The group with the absorber and curing salt (AP3) showed improved aroma, taste, and juiciness. Acidity was primarily affected by the addition of bacterial culture and NaCl (AP1), as well as by AP2 and AP3. The most pleasing sweetness was achieved by adding bacterial culture and NaCl to samples with the absorber (AP1). Samples with the best consistency when packaged with the absorber were those with bacterial culture and celery powder (AP2). In summary, among dried meat samples with oxygen absorber, those with added curing salt (AP3) had the best overall sensory evaluation compared to the negative control with NaCl (AC). For samples without an oxygen absorber, the highest overall sensory scores were in the group with bacterial culture and celery powder, surpassing the control with NaCl (C). The use of an oxygen absorber and curing salt proved to be effective in the production of biltong, but replacing the curing salt with NaCl and the addition of celery powder and bacterial culture significantly improved the sensory evaluation compared to the other groups (except AP3).

EFFECT OF NITRATE-REDUCING BACTERIA AND CELERY ROOT (APIUM GRAVEOLENS VAR. RAPACEUM) ON THE SENSORY PROPERTIES OF DRIED MEAT “BILTONG”

The objective of our study was to assess the effect of nitrate-reducing bacteria and natural nitrate source on the sensory properties of dried meat biltong. Appearance, colour on the cut, aroma, taste and juiciness, acidity, sweetness, and consistency were evaluated. The members of the panel gave their ratings between 1 and 5 according to the characteristics of the samples, with 1 being the lowest rating and 5 being the best rating. In the sensory evaluation of dried meat samples without oxygen absorber packaging, the group (P2) with bacterial culture, celery powder, and NaCl showed the highest scores for appearance, taste, juiciness, acidity, and consistency. Notably, P3 samples had significantly lower consistency scores compared to P2. Additionally, sample P1, with bacterial culture and NaCl, improved the colour on the cut compared to the negative control (C) with only NaCl. The best aroma and sweetness results were in the P3 group with curing salt, although these differences were not statistically significant (P ≥ 0.05). The sensory evaluation of dried meat samples packaged with an oxygen absorber revealed that the combination of bacterial culture, celery powder, and NaCl (AP2) had the most positive influence on appearance, colour on the cut, and consistency. The group with the absorber and curing salt (AP3) showed improved aroma, taste, and juiciness. Acidity was primarily affected by the addition of bacterial culture and NaCl (AP1), as well as by AP2 and AP3. The most pleasing sweetness was achieved by adding bacterial culture and NaCl to samples with the absorber (AP1). Samples with the best consistency when packaged with the absorber were those with bacterial culture and celery powder (AP2). In summary, among dried meat samples with oxygen absorber, those with added curing salt (AP3) had the best overall sensory evaluation compared to the negative control with NaCl (AC). For samples without an oxygen absorber, the highest overall sensory scores were in the group with bacterial culture and celery powder, surpassing the control with NaCl (C). The use of an oxygen absorber and curing salt proved to be effective in the production of biltong, but replacing the curing salt with NaCl and the addition of celery powder and bacterial culture significantly improved the sensory evaluation compared to the other groups (except AP3).

Pathogenicity and Management of Damping-off Disease Caused by Fusarium equiseti in Apple (Malus × domestica Borkh.)

In 2022, apple seedlings showed symptoms of damping off with more than 50% disease incidence. The causal organism was isolated from infected seedlings which showed a white-colored mycelium with yellow to pale brown pigmentation on PDA. Additionally, microscopic observation revealed macroconidia and abundant chlamydospores in the pure culture. Based on morphology, sequences of ITS, Tef 1 alpha, and LSU genes the identity of the fungus was confirmed as Fusarium equiseti. Koch's postulates were confirmed by inoculating wheat grains infected with an isolated fungus to healthy apple seedlings. After four weeks of incubation, inoculated seedlings showed damping-off symptoms.To the best of our knowledge, this is the first report of damping-off disease of apple seedlings caused by F. equiseti from India. In-vitro evaluation of eight fungicides and nine botanicals was done against the pathogen through the poison food technique. The result revealed that fungicides Propiconazole at 1 ml L-1, Propiconazole + Difenoconazole at 1 ml L-1, Fluopyram + Tebuconazole at 0.62 ml L-1 and botanicals Curcuma longa at 5-15 % and Allium sativum at 10-15 % exhibited more than 80% inhibition therefore selected for pot studies. In pot studies, drenching of Propiconazole at 1 ml L-1 and Fluopyram + Tebuconazole at 0.62 ml L-1 three times at 15-day intervals yielded 90 % seedling survival followed by Propiconazole + Difenoconazole (83.33 %) and C. longa (5%) crude extract (56.67%). Present findings suggest that drenching of Propiconazole at 1 ml L-1 and Fluopyram + Tebuconazole at 0.62 ml L-1 are effective treatments and recommended to nursery growers for the management of damping-off in apple seedlings.

Characteristics of Bacteria in Urine and Stones from Patients Treated with Percutaneous Nephrolithotomy and Association with Postoperative Infection.

The purpose of this study was to identify bacterial differences between urine cultures (UC) and stone cultures (SC) in patients with complex kidney stones and to determine any correlation with post-percutaneous nephrolithotomy Systemic Inflammatory Response Syndrome (SIRS). Perioperative data of 1055 patients with complex kidney stones treated with first-stage Percutaneous Nephrolithotomy (PCNL) from September 2016 until September 2021 were included. Preoperative mid-stream urine samples and surgically obtained stone material were subjected to bacterial culture and antibiotic sensitivity tests. Preoperatively, antibiotic usage was determined by the UC or local bacterial resistance patterns. After PCNL treatment, antibiotic selection was guided by stone bacterial culture result and clinical symptoms. The effect of different preoperative antibiotic regimens based on urine cultures and postoperative antibiotic treatment based on stone cultures were assessed. Positive stone cultures (SC+) were significantly more common than positive urine cultures (UC+) (31.9% vs 20.9%, p < 0.05). Escherichia coli (E. coli) was the most common uropathogen in both urine (54.3%) and stones (43.9%). The difference was statistically significant (p < 0.05). Moreover, UC+SC-, UC-SC+, UC+SC+, and preoperative serum creatinine were independent risk factors of postoperative SIRS. The incidence of SIRS in the UC+SC+ patients with different bacteria in stones and urine (51.6%) was higher than that in other culture groups. The antibiotic resistance of E. coli inside the stone was increased when prolonged preoperative antibiotics were administered to UC+ patients. The bacterial spectrum and positive outcome of culture in urine and stones were significantly different. The incidence of postoperative SIRS was highest in patients with UC+SC+ but with different bacteria strains. Prolonged pre-surgical antibiotic treatment apparently induced higher drug resistance for bacteria inside the stone.

Electrodeposition of myristate based superhydrophobic coatings on steel with enhanced corrosion resistance and self-cleaning property

In recent decades, superhydrophobic (SHP) coatings have gained significant attention because of their versatile applications. Superhydrophobic coating is considered as a promising solution to combat corrosion and biofouling issues encountered by steel components in various industries. Using a one-step electrodeposition technique, a superhydrophobic coating with strong corrosion resistance and anti-biofouling property was fabricated on carbon steel in this work.With a water contact angle (WCA) of 170.3 ± 4.2° and a sliding angle (SA) of ~1°, the wettability of the surface was optimized by varying the electrodeposition potential and deposition time. The as-developed superhydrophobic carbon steel surfaces were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), laser Raman spectroscopy (LRS), Energy dispersive X-ray (EDS) spectroscopy and X-ray diffraction (XRD). Employing field emission scanning electron microscopy (FESEM), the morphology of the superhydrophobic coatings was examined. Potentiodynamic polarization (PDP) technique was used to study the anti-corrosion property of SHP coating and bare sample in 3.5 wt% NaCl solution. The superhydrophobic coating was found to exhibit 99 % corrosion inhibition efficiency. In addition, the biofouling resistance of the coating was evaluated in both gram-negative and gram-positive bacterial cultures and compared with the uncoated sample. Total viability count (TVC) for the SHP coated samples was 5 orders less as compared to the uncoated sample exposed to gram-negative bacterial culture. Similarly, 4 orders reduction in TVC was estimated for the SHP coated sample as compared to the uncoated sample in gram-positive bacterial culture. The impact of superhydrophobic coating on the corrosion performance and biofouling properties of carbon steel was investigated along with the self-cleaning property and robustness of the coating.

Prevalence of Dichelobacter nodosus in western Austrian sheep flocks: Comparison of bacterial cultures, clinical foot rot and lameness with PCR and analysis of sample pooling for PCR diagnosis.

Ovine foot rot is a highly contagious and multifactorial claw disease, caused by Dichelobacter nodosus (D. nodosus) and is the main cause of lameness in sheep. The aim of this cross-sectional study was to determine the prevalence of D. nodosus in western Austria both at animal and farm levels. Real-time PCR was evaluated in comparison with clinical and bacteriological investigations from interdigital foot swabs to detect D. nodosus-infected animals. In addition, the use of pooled four-foot swabs to detect foot rot was determined. In course of the study a total of 3156 sheep from 124 farms were examined for lameness and clinical signs of foot rot. The found flock prevalence of D. nodosus was 30,65 % with bacterial culture showing a sensitivity of 75,0 % and a specificity of 100,0 % (p < 0,001) respectively, compared with PCR. Furthermore, clinical foot rot scores (Ckorr = 0,87; p < 0,001) and lameness scores (Ckorr = 0,71; p < 0,001) highly correlated with the detection of D. nodosus by PCR. The result showed that the clinical examination can be used to identify animals infected with D. nodosus in flocks, but PCR must be used to confirm the diagnosis. D. nodosus could be detected equally well with risk-based pools-of-five samples as with undiluted samples (p < 0,001), suggesting that a pool-of-five samples might be a suitable and cost-effective method for detecting D. nodosus in sheep flocks. This study provides an overview of foot rot in Tyrolean sheep flocks and outlines the possibilities and limitations of the various diagnostic tools for D. nodosus. Further studies to investigate possible influencing factors, including alpine pasturing, management factors and biosecurity predisposing to foot rot are necessary for the design of effective future control programs in alpine regions.