Agar Method Research Articles

An IncN-ST7 epidemic plasmid mediates the dissemination of carbapenem-resistant Klebsiella pneumoniae in a neonatal intensive care unit in China over 10 years

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has widely disseminated globally, but its epidemiological characterization and clinical significance in paediatric patients are not well understood. In this study, we aimed to trace the dissemination dynamics of CRKP in the neonatal intensive care unit (NICU) of a tertiary hospital over a 10-y period. We collected 67 non-duplicate K. pneumoniae species complex isolates from the NICU with patient metadata during 2009-2018. Antimicrobial susceptibility was determined by the agar or broth microdilution method. Risk factors for CRKP-positive patients were identified by univariate and multivariate analysis. Genetic characterization was dissected by whole-genome sequencing. Plasmid transmissibility, stability, and fitness were assessed. Thirty-four of 67 isolates (50.75%) were identified as CRKP. Premature rupture of membranes, gestational age, and invasive procedures are independent risk factors for CRKP-positive patients. The annual isolation rate of CRKP varied between 0% and 88.9%, and multiple clonal replacements were observed during the study period, which could be largely due to the division of the NICU. All but one CRKP produced IMP-4 carbapenemase, which was encoded by an IncN-ST7 epidemic plasmid, suggesting that the IncN-ST7 plasmid mediated the CRKP dissemination in the NICU over 10 y. The same plasmid was found in several CRKP isolates from adult patients, of which two ST17 isolates from the neurosurgery department shared a high homology with the ST17 isolates from the NICU, indicating possible cross-departmental transmission. Our study highlights the urgent need for infection control measures targeting high-risk plasmids like IncN-ST7.

Methylene Blue Assisted Electrochemical Detection of Bacterial Biofilm.

This paper presents a novel electrochemical transduction method for the rapid and straightforward detection of bacterial biofilm. Briefly, fifteen isolates from various sources were collected and evaluated for their ability to generate biofilm. The Congo red-based agar method and the tube test were used for preliminary screening. A microtiter experiment was also performed to quantitatively examine the screening results and validate the outcomes of the proposed methylene blue-based electrochemical detection method. Electrochemical sensing was performed on the two selected isolates using methylene blue as a redox indicator. For optimization goals, several methylene blue concentrations were studied. Methylene blue at a concentration of 0.4mM was used for the analysis conclusion. The developed electrochemical method displayed a linear R2 value of 0.9747. The new electrochemical approach demonstrated great sensitivity and rapid response compared to conventional microtiter test methods.

Foeniculum vulgare Mill. ve Pimpinella anisum L. (Apiaceae) Türlerinin Uçucu Yağlarının Antimikrobiyal Aktivitesi

Today, essential oils are considered safe substances and can be used as antibacterial additives. Pimpinella anisum L. (Aniseed) and Foeniculum vulgare Mill. var. dulce (fennel) species are of great economic importance. It is among the medicinal and aromatic plants cultivated in wide areas in our country. In this study, it was aimed to determine the antimicrobial properties of essential oils obtained from Foeniculum vulgare Mill. and Pimpinella anisum L plants. The essential oils of the species were obtained by using the distillation method. The antimicrobial activities of essential oils by hand were studied using the hollow agar method. Known to be medically important in food, cosmetics and pharmaceutical products Enterobacter aerogenes (ATCC 13048), Enterococcus faecalis (ATCC 29212), Salmonella enteritidis (ATCC 13075), Staphylococcus aureus subsp. aureus (ATCC 25923), Escherichia coli (ATCC 25922) and Serratia marcescens (ATCC 13880) evaluated against pathogen and microbial contaminants. While Foeniculum vulgare showed results parallel to the antibiotic used as standard, no antibacterial activity was observed in Pimpinella anisum L.

The Prevalence of Vibrio cholerae and Vibrio parahaemolyticus Virulence Genes and Multiple Antibiotics Resistant (MAR) Assessment from Local Shrimp Farm in Sarawak

Excessive and improper antibiotic use in animals raised for human consumption can increase the risk of antibiotic-resistant infections, causing more harm and higher treatment costs. This study examined the virulence genes and antibiotic susceptibility of Vibrio cholerae and V. parahaemolyticus, two bacteria that can affect public health. A total of 32 water samples were collected from August to December 2021 from a shrimp farm in Sarawak. Ten (n = 10) V. cholerae and ten (n = 10) V. parahaemolyticus presumptive isolates were identified and purified using selective agar and duplex-PCR method. The results showed that 70% of V. cholerae isolates contained rtxA and 90% of V. cholerae isolates contained rtxC while tdh and trh were not found in V. parahaemolyticus isolates. Antibiotic susceptibility testing showed that all V. cholerae and V. parahaemolyticus isolates were resistant to at least one antibiotic with the mean Multiple Antibiotic Resistance (MAR) indices of 0.34 for V. cholerae and 0.24 for V. parahaemolyticus. The MAR index of 0.20 and greater indicates that antibiotics are heavily contaminating the shrimp farm water. This study highlights the need for the proper administration of antibiotics in shrimp farming environments to reduce the risk of antibiotic-resistant infections caused by V. cholerae and V. parahaemolyticus. Water treatment should also be implemented before being released back to the environment to lessen the negative impact brought by the rearing of shrimp from a highly contaminated source.

ASSESSMENT OF ANTIBIOTICS RESISTANCE AND BIOFILM PRODUCTION AMONG BACTERIAL SPECIES ISOLATED FROM CONTACT LENSES

Contact lenses (CLs) wearing has been increased globally during recent decades, which is one of the main risk factors for developing several ocular infections. Resistant CLs bacterial infections are mainly due to the CLs contamination by bacteria producing biofilm. This study was aimed to assessment of antibiotics resistance and biofilm production among bacterial species isolated from contact lenses in Mukalla city, Hadhramout, Yemen. This cross-sectional study was carried out on 298 participants women during a period from October 2022 to January 2023. The CLs swab samples were collected, then inoculated onto culture media and incubated aerobically at 37°C for 24 hrs. The bacterial isolates were identified by conventional bacteriological methods of cultural characteristics, Gram staining and biochemical test. Antibiotics susceptibility testing was performed by disc diffusion method. Bacterial biofilm production on CLs was detected by tube method (TM) and Congo red agar (CRA) method. The prevalence of CLs bacterial infection was 54.4%. Enterobacter spp. 37.1%, followed by Escherichia coli 28.4%, Pseudomonas aeruginosa 11.7%, Klebsiella pneumoniae 6.8% were the most common Gram-negative isolated from CLs. Staphylococcus epidermides 3.7% and other coagulase negative staphylococci (CoNS) 12.3% were the most common species of Gram-positive bacteria isolated from CLs. The CRA method was found to be effective phenotypic screening method for detection of biofilm production of bacterial isolates from CLs. Prevalence of antibiotics resistance and multi-drug resistance (MDR) biofilm producing strains was found. In conclusion, there is a high prevalence of CLs use by females in Mukalla city, Hadhramout especially for cosmetic purposes. CLs infection due to improper care practices leads to eye complications. Increasing awareness is crucial to avoid identified risk factors for ocular infection.

Prevalence Study of Biofilm Marker ica D Gene among Coagulase Positive Staphylococcus of Mastitic Origin

Bovine Mastitis is an inflammation of the mammary gland, usually due to microbial infection, which causes economic loss to dairy producer every year. Staphylococcus is one of the most common pathogens responsible for contagious mastitis in bovines. The aim of this study was to identify coagulase positive Staphylococci isolated from bovine subclinical mastitis. In vitro biofilm forming ability of the isolates, an important virulence factor of mastitogen and prevalence of biofilm marker icaD gene among the isolates. In the present study, 70 isolates were biochemically identified as S. aureus. Biochemically characterized strains of S. aureus were screened for biofilm formation. Phenotypic detection of biofilm formation of S.aureus were done by two methods, namely, Congo Red Agar (CRA) method and Tube Method (TM). The frequency of biofilm formation in S. aureus strains was 28.57 per cent on CRA plates while 71.42 per cent were biofilm non-producers. The frequency of biofilm formation in S. aureus strains was 38.57 per cent in total as shown by tube method while 61.42 per cent were biofilm non-producers. Employing PCR, molecular detection technique of icaD gene was carried out. In this study, 72.85 per cent S. aureus strains were found to be positive for icaD gene which produced an amplicon of 381bp.

Phytochemicals Analysis, In Vitro Antibacterial Activities of Extracts, and Molecular Docking Studies of the Isolated Compounds from Melhania zavattarii Cufod Leaves.

Melhania zavattarii Cufod is an endemic plant species to Ethiopia and is used to treat ailments related to kidney infection. The phytochemical composition and biological activity of M. zavattarii have been not reported yet. Therefore, the present work aimed to investigate phytochemical constituents and evaluate the antibacterial activity of different solvents' leaf extracts and analyze the molecular binding capacity of isolated compounds from the chloroform leaf extract of M. zavattarii. Accordingly, preliminary phytochemical screening was tested by using standard procedures and the result indicated that phytosterols and terpenoids as major and others like alkaloids, saponins, flavonoids, tannins, phlobatannin, and coumarins were detected as minor in extracts. Antibacterial activity of the extracts was evaluated using the disk diffusion agar method, and the activities revealed that chloroform extract showed the highest inhibition zones, 12.08 ± 0.38, 14.00 ± 0.50, and 15.58 ± 0.63 mm against Escherichia coli at 50, 75, and 125 mg/mL concentrations, respectively, compared to that of n-hexane and methanol extracts at respective concentrations. Methanol extract showed the highest zone of inhibition 16.42 + 0.52 against Staphylococcus aureus at 125 mg/mL concentration compared to that of n-hexane and chloroform extracts. Two compounds, namely, β-amyrin palmitate (1) and lutein (2) were isolated and identified for the first time from the chloroform leaf extract of M. zavattarii, and structural elucidations of these compounds were accomplished by using spectroscopic methods (IR, UV, and NMR). For the molecular docking study, 1G2A, which is a protein of E. coli and chloramphenicol standard target, was selected. Binding energies of -9.09, -7.05, and -6.87 kcal/mol were calculated for β-amyrin palmitate, lutein, and chloramphenicol, respectively. The drug-likeness property result indicated that both β-amyrin palmitate and lutein violated two rules of Lipinski's rule of five with molecular weight (g/mol) > 500 and LogP > 4.15. In the near future, further phytochemical investigation and biological activity evaluation should be conducted on this plant.

Virulence Factors of Clinical and Fecal Isolates of Enterococci Species

Enterococci species are known commensals of the gastrointestinal flora; however, in recent years, they have emerged as important nosocomial pathogens that possess many virulence factors that are attributed to the pathogenesis of diseases caused by them. The study evaluated and compared the virulence factors of Enterococci isolated from fecal and clinical samples. From the obtained isolates, the clinical enterococcal isolates produced 35%, 20%, and 50%, and fecal isolates produced 23%, 13%, and 13% gelatinase, hemolysin, and biofilm, respectively. Biofilm production determined by the Congo Red agar, tube, and microtiter plate methods was 23%, 39%, and 49%, respectively. The sensitivity of the Congo Red agar and tube method compared to the microtiter plate method was 27% and 46%, respectively, whereas the specificity of both tests was 79%. This study showed that biofilm production plays a significant role in the pathogenesis of diseases caused by Enterococci. Detection of biofilm production using the microtiter plate method is more sensitive and specific than the Congo Red agar and tube method.

Detection of biofilm formation in multi-drug resistant Staphylococcus aureus among clinical isolates in Zaria metropolis, Kaduna, Nigeria

Antimicrobial resistance are associated with several virulence factors such as biofilm. The biofilm formation ability of S. aureus complicates effective therapeutic management of infections. In this research, we intend to observe biofilm formation in S. aureus using two in vitro phenotypic methods: tissue culture plate and Congo red agar as well as biofilm associated genes Ica A B & D and 16SrRNA. A total of 150 presumptive coagulase positive staphylococcal isolates from all specimens (blood, urine, high vaginal swab, wound swab, ear swab, endocervical swab) submitted to the microbiology laboratory of the selected hospitals were collected. Seventy-three (73) or 48.7% of the isolates were identified as coagulase positive Staphylococcus using microbiology standard methods (tube coagulase test, growth on mannitol salt agar & Dnase agar). Using microgen staph identification kit, the isolates were further characterized into various Staph spp. Disc agar diffusion method was used for eleven (11) antibiotics susceptibility test while vancomycin screening agar and BMD (Broth Micro dilution) MIC test was used for vancomycin susceptibility evaluation. Indirect observation of biofilm was performed using congo red agar (CRA) and Microtitre plate assay method. PCR and sequencing were conducted on the isolates to molecularly detect the presence of 16SrRNA, IcaA, IcaB, IcaD genes. Susceptibility of S aureus (21%) isolates tested against 12 different categories of antibiotics shows 4(27%) not multidrug resistant (MDR), 7(47%) were MDR and 4 (27%) were extensively drug resistant (XDR). High percentage (74%) of Multiple antibiotic resistant index at ≥0.3 suggested that the isolates originated from an environment where antibiotics are often used. Biofilm assessment of MDR S aureus isolates revealed that 9(82%) and 11 (100%) of the isolates were biofilm formers using Congo Red Agar method and Microtiter plate assay respectively. All isolates amplified with 16SrRNA primer signifying all are S. aureus, 100% of the isolates amplified with IcaA, 90% isolates amplified with IcaD, and 50% isolates amplified with IcaB. We can conclude that there is high prevalence of Biofilm forming S. aureus strains in the hospitals studied. This result should be born in mind by clinicians while prescribing medication for S. aureus positive conditions. Hospital managements should be proactive in preventing the preservation of the biofilm formers in their hospital environment through adequate sanitary and disinfection protocols. It is also necessary for clinician to note that nitrofurantoin, linezolid and vancomycin were most effective against the biofilm producing S. aureus and microtitre plate assay method was observed to be most reliable assay in the study of biofilm.

Isolation and characterization of a novel phage belonging to a new genus against Vibrio parahaemolyticus

BackgroundVibrio parahaemolyticus is a major foodborne pathogen that contaminates aquatic products and causes great economic losses to aquaculture. Because of the emergence of multidrug-resistant V. parahaemolyticus strains, bacteriophages are considered promising agents for their biocontrol as an alternative or supplement to antibiotics. In this study, a lytic vibriophage, vB_VpaM_R16F (R16F), infecting V. parahaemolyticus 1.1997T was isolated, characterized and evaluated for its biocontrol potential.MethodsA vibriophage R16F was isolated from sewage from a seafood market with the double-layer agar method. R16F was studied by transmission electron microscopy, host range, sensitivity of phage particles to chloroform, one-step growth curve and lytic activity. The phage genome was sequenced and in-depth characterized, including phylogenetic and taxonomic analysis.ResultsR16F belongs to the myovirus morphotype and infects V. parahaemolyticus, but not nine other Vibrio spp. As characterized by determining its host range, one-step growth curve, and lytic activity, phage R16F was found to highly effective in lysing host cells with a short latent period (< 10 min) and a small burst size (13 plaque-forming units). R16F has a linear double-stranded DNA with genome size 139,011 bp and a G + C content of 35.21%. Phylogenetic and intergenomic nucleotide sequence similarity analysis revealed that R16F is distinct from currently known vibriophages and belongs to a novel genus. Several genes (e.g., encoding ultraviolet damage endonuclease and endolysin) that may enhance environmental competitiveness were found in the genome of R16F, while no antibiotic resistance- or virulence factor-related gene was detected.ConclusionsIn consideration of its biological and genetic properties, this newly discovered phage R16F belongs to a novel genus and may be a potential alternate biocontrol agent.

Determination of Pollinator Characteristics of Some Hazelnut Genotypes

This research was carried out in Karasu, Kocaali and Arifiye districts of Sakarya Province to determine the suitable pollinators for Çakıldak hazelnut cultivar (Corylus avellana) in 2021-2022. In the study, 27 genotypes that were late male flowering, formed a large amount of catkins, had high pollen quality, had round nut shape and short husk length were examined. Pollen viability was detected according to 2, 3, 5,-Triphenyl Tetrazolium Chloride (TTC). Pollen viability of the genotypes was ranged from 22.3% to 93.7% according to the TTC method. According to the agar method, pollen germination rate was determined between 15.6% and 78.1% at 20% sucrose concentration containing 1% agar. 89% of the genotypes were round, 11% were in the oblong nut group. It was determined that most of them amount of male inflorescences (catkins) depending on the tree crown volume and age. T-22KRS02, T-22KRS03, T-22KRS07, T-22KRS08, T-22KRS09, T-22KRS10, T-22KRS11, T-22KCL11, T-22KCL14, T-22KCL16 and Mincane were selected to be evaluated in the second phase of the study.

Growth and Antibiotic Sensitivity Status of Bacillus spp. associated with Abalone (Haliotis asinina) as Probiotic Candidate Selection

The use of probiotics is an innovation in an effort to increase production and fight pathogens in aquaculture cultivation environments. Probiotic candidate microorganisms are selected selectively to ensure that the probiotics used are safe and provide benefits for the host and the environment. This study aims to select probiotic candidates based on the aspects of growth and sensitivity to antibiotics from 4 isolates of Bacillus from abalone (Haliotis asinina). Growth observations were carried out by turbidimetric method using a spectrophotometer at a wavelength of 600 nm in SWC media, and antibiotic sensitivity was tested using Rifampicin, Gentamicin, Kanamycin, and Erythromycin antibiotics using the well-diffusion agar method. The growth analysis of isolates was described by a growth curve based on the OD value, and antibiotic susceptibility based on the diameter of the inhibition zone. The results showed that the growth of the four isolates of Bacillus spp. had a short lag phase, ranging from 1-2 hours, an exponential phase ranging from 15 hours to B. pumilus SLK1 and B. licheniformis SLK2 isolates, and 12 hours to B. coagulans CaK1 and B. coagulans CaK6 isolates. Antibiotic sensitivity showed that B. coagulans CaK1 isolates were sensitive to all the tested antibiotics, while B. pumilus SLK1 isolates, B. licheniformis SLK2, and B. coagulans CaK6 were only sensitive to Rifampicin and Gentamicin antibiotics. The ideal probiotic candidate is an isolate with good growth and does not have resistance properties, based on the results of this study CaK1 isolate has the potential as a probiotic candidate

Reliability of a terbinafine agar containing method for the screening of dermatophyte resistance.

The increase in terbinafine resistance worldwide due to Trichophyton indotineae underlies the need for surveillance networks, deploying easy to perform methods to correctly identify resistant isolates and thereby reduce their spread. In the present study, we evaluated the performances of the terbinafine containing agar method (TCAM). Different technical parameters, such as culture medium (RPMI agar [RPMIA] or Sabouraud dextrose agar [SDA]) and inoculum size, were evaluated. Our study showed that terbinafine susceptibility determined using the TCAM was reliable and independent of the inoculum or medium used. We then performed a multicenter, blinded study. Five isolates of T. indotineae and 15 of genotype I or II of T. interdigitale, including five terbinafine-resistant isolates (four T. indotineae, one T. interdigitale) were sent to eight clinical microbiology laboratories. Each laboratory analyzed the 20 isolates' terbinafine susceptibility by the TCAM using both culture media. TCAM allowed all participants to correctly determine the terbinafine susceptibility of analyzed isolates without prior training. All participants agreed that the dermatophyte tested, regardless of species or genotype, grew better on SDA than on RPMIA medium but accumulated fungal growth after 14 days eventually minimized the effect of this difference. In conclusion, TCAM is a reliable, easy to perform screening method for assessing terbinafine resistance. However, despite good performances, TCAM is a qualitative method and minimal inhibitory concentrations must be determined by the EUCAST standardized method to follow the evolution of terbinafine resistance levels.

Mutant Prevention Concentration, Frequency of Spontaneous Mutant Selection, and Mutant Selection Window-a New Approach to the In Vitro Determination of the Antimicrobial Potency of Compounds.

The analysis of antimicrobial activity is usually MIC- and minimal bactericidal concentration (MBC)-focused, though also crucial are resistance-related parameters, e.g., the frequency of spontaneous mutant selection (FSMS), the mutant prevention concentration (MPC), and the mutant selection window (MSW). In vitro-determined MPCs, however, are sometimes variable, poorly repeatable, and not always reproducible in vivo. We propose a new approach to the in vitro determination of MSWs, along with novel parameters: MPC-D, MSW-D (for dominant mutants, i.e., selected with a high frequency, without a fitness loss), and MPC-F, MSW-F (for inferior mutants, i.e., with an impaired fitness). We also propose a new method for preparing the high-density inoculum (>1011 CFU/mL). In this study, the MPC and MPC-D (limited by FSMS of <10-10) of ciprofloxacin, linezolid, and novel benzosiloxaborole (No37) were determined for Staphylococcus aureus ATCC 29213 using the standard agar method, while the MPC-D and MPC-F were determined by the novel broth method. Regardless of the method, MSWs1010 of linezolid and No37 were the same. However, MSWs1010 of ciprofloxacin in the broth method was narrower than in the agar method. In the broth method, the 24-h incubation of ~1010 CFU in a drug-containing broth differentiates the mutants that can dominate the cell population from those that can only be selected under exposure. We consider MPC-Ds in the agar method to be less variable and more repeatable than MPCs. Meanwhile, the broth method may decrease discrepancies between in vitro and in vivo MSWs. The proposed approaches may help establish MPC-D-related resistance-restricting therapies.

Fungi on bean seeds obtained from growers in Isparta province

The fungal load of seeds is among the factors related to seed quality. Seed-borne fungi can cause significant crop losses and may produce mycotoxins, which are harmful to human health. This study aimed to determine the seed-borne fungi of bean, which is among one of the most important crops cultivated in Isparta province. Seed samples from the 2015-2016 vegetation period, obtained from bean growers in Isparta province were used in this study. The fungal load of randomly selected 200 seeds were investigated by blotter and agar methods and prevalence and infestation rates of the fungi were determined. As a result, 41 species of fungi belonging to 26 genera were determined on 62 seed samples. The blotter method yielded 25 genera while 20 genera were determined by the agar method. Alternaria, Aspergillus, Cladosporium, Fusarium, Penicillium and Rhizopus species were the most common fungi found on almost all of the samples, for both methods. Infestation rates of these fungi were also high on bean seeds. Prevalence and infestation rates of the fungi were generally higher in the blotter method, except for Fusarium and Verticillium species that were determined on the seed samples in higher frequencies by the agar method. Absidia, Arthrinium, Epicoccum, Nigrospora, Scopulariopsis and Stachybotrys species were determined only by the blotter method, while Seimatosporium sp. was found by the agar method. Alternaria, Fusarium, Rhizoctonia, Stemphylium and Verticillium species are known as pathogenic fungi and may cause diseases on bean plants. Aspergillus and Penicillium species are saprobic fungi producing mycotoxins, so their presence on the seeds is also important.

Synthesis, structural and spectroscopic properties of Co(II), Ni(II) and Cu(II) complexes with 2-((2-chlorobenzylidene)amino) acetohydrazide hydrate and their Antimicrobial and antioxidant activities

The current study was purposed to prepare Co(II), Ni(II) and Cu(II) complexes with the ligands derived from 2-chlorobenzaldehyde, glycine and hydrazine hydrate. The obtained compounds were characterized by different physicochemical studies such as elemental analysis, atomic absorption, molar ratio analysis, electronic absorption (UV-Vis spectroscopy), magnetic properties, FTIR spectroscopy, 1H�NMR, 13C-NMR, conductance measurements and XRD. Antimicrobial and antioxidant activities were also calculated. The antibacterial activity was evaluated by the diffusion method against two Gram-positive and two Gram-negative bacteria, while antifungal activity was assessed against two fungal strains by using the agar method. The ligand with Schiff base and hydrazide groups and its complexes showed better biological activity. The results showed that the most metal complexes have much higher antibacterial and antifungal activity compared to the parent ligand. The antioxidant activity of 3.7453 mg of the ligand exhibited excellent activity as the activity of 1 mg of ascorbic acid which is used as a standard antioxidant.

Detection of Antibiotic Resistance and Biofilm- Producing Ability of Staphylococcus Species in Clinical Isolates

Background Staphylococci are responsible for life-threatening infections in hospitals and community. Their ability to produce multiple virulence factors and antibiotic resistance is an important reason of high mortality in staphylococcal infections. Biofilm production by these organisms makes it difficult to treat. Most of the treating antibiotics are failing and making it a matter of concern. Aims This study aims to detect the increased antibiotic resistance in biofilm-producing Staphylococcus and to compare the performance of three potential methods of detection. Methods A total of 81 isolates of staphylococci including coagulase negative staphylococci (CoNs), methicillin resistant S. aureus (MRSA), and methicillin sensitive S. aureus (MSSA) are included in this study. After the identification, an antibiotic sensitivity test was performed. Biofilm detection was done by three different methods: Congo red agar method, tube adherence method, and microtiter plate method. Result Out of the 81 samples, 37 CoNs, 17 MRSA, and 27 MSSA were identified. Out of them we got 43 (53%) biofilm producers by Congo red agar method, 40 (49%) by tube adherence method, and 52 (64%) producers by tissue culture plate/microtiter plate method. Most of the biofilm producers showed multiple drug resistance. Conclusion We found out that the microtiter plate method is sensitive and reliable as compared with the other two methods. Antibiotic resistance was found to be very common in biofilm producers. This was due to the resistance developed as a result of the matrix that does not let the antibiotic bind with the organisms. This can make the treatment of Staphylococcus very difficult in the future as the rate of drug resistance is faster as compared with newly emerging antibiotics.

Biofilm formation and antibiotic resistance profiles of water-borne pathogens

Water sources (surface water, drinking water, rivers, and ponds) are significant reservoirs for transmitting antibiotic-resistant bacteria. In addition, these waters are an important public health problem because they are suitable environments for transferring antibiotic resistance genes between bacterial species. Our study aimed to assess the prevalence of Extended-spectrum beta-lactamase (ESBL) producing isolates in water samples, the susceptibility of the isolates to the specified antibiotics, the determination of biofilm ability, antibiotic resistance genes, and the molecular typing of the isolates. For this purpose, Polymerase chain reaction (PCR) and Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) analyses were used. Out of 70 isolates, 15 (21%) were ESBL producing, and sent for the MALDI-TOF analysis, where Escherichia coli, Acinetobacter calcoaceticus, Enterobacter bugandensis, Acinetobacter pittii, Pseudomonas aeruginosa, Acinetobacter junii, Pseudomonas oleovorans, and Enterobacter ludwigigii were identified. Moreover, colistin resistance genes (mcr 1/2/6, mcr 4, mcr 5, mcr 3/7, and mcr 8), ESBL-encoding genes (blaSHV, blaTEM, and blaCTX-M) and carbapenemase genes (blaNDM, blaOXA-48, and blaKPC) using molecular analysis (PCR) were confirmed. The colistin resistance gene was detected at 80% (12/15) in the isolates obtained. The distribution of these isolates according to resistance genes was found as mcr 1/2/6 4 (20%), mcr 3/7 3 (13%), and mcr 5 (40%). Additionally, the isolates harbored blaSHV(6.6%) and blaTEM (6.6%) genes. However, blaNDM, blaOXA-48, blaKPC, and blaCTX-M genes were not detected in any isolates. According to the Congo red agar method, seven (46.6%) isolates showed negative biofilm ability, and eight (53.3%) showed moderate biofilm ability. However, the microplate method detected weak biofilm in 53.3% of the isolates. In conclusion, this study provides evidence for the existence of multidrug-resistant bacteria that co-exist with mcr and ESBL genes in water sources. These bacteria can migrate to other environments and pose increasing threats to public health.

DETEKSI DAN IDENTIFIKASI JAMUR PATOGEN TERBAWA BENIH VARIETAS PADI LOKAL DI KABUPATEN KAPUAS

This study was aimed to detect and identify seed-borne pathogenic fungi in six local rice varieties of Siam Unus, Karangdukuh, Mayang, Gumpal Kuning, Gumpal Putih, and Siam Arjuna in Kapuas Regency. In addition, the objective of this study was also to determine the effect of seed pathogens on the physiological quality and the percentage of infected seeds.&#x0D; The research location was at the Agricultural Cultivation Laboratory, Faculty of Agriculture, University of Palangka Raya, and the study was carried out from September 2020 to February 2021. Seed health testing used the filter method (blotter test), isolation and identification of seed-borne pathogenic fungi using the agar method. The variables observed included macroscopic morphology of pathogens in petri dishes and microscopic evaluation using a compound microscope, seed germination, percentage of infected seeds, frequency of microorganism findings and pathogenicity tests on seed germination.&#x0D; Based on the results of the study, the identified pathogenic fungi carried by local varieties of rice seeds in Kapuas district were Aspergillus spp., A. flavus, A. niger, Curvularia sp. and Oidium sp., however these pathogens did not affect seed germination. The highest numbers of microorganisms observed on the agar method was Aspergillus spp. (37.5%), followed by Curvularia sp. (29%), whereas in the blotter test method the frequency of the fungus Curvularia sp. only 5.6%. The frequency of finding A. flavus and A. niger on the agar method was lower at 21.8%, while the fungus Oidium sp. was detected in very low percentage for only 0.9%. The pathogenic fungus Oidium sp. showed the highest level of pathogenicity in seeds reaching 21.7%, while the pathogenic A. niger, Curvularia sp. and A. flavus showed a lower infection rate, at 13.9% to 17.8% respectively. These pathogenic fungi might cause the seeds to not germinate normally such as leading to necrosis of the hypocotyl and plumules, stunted germination growth, and death of seed germination.&#x0D; Keywords: Detection, identification, seed-borne pathogens, local rice varieties, Kapuas

Antimicrobial activity of moringa leaf infusion on Escherichia coli isolate from Musca domestica L

The Moringa oleifera can be used as a medium for the prevention and treatment of infectious diseases such as diarrhea. Diarrhea can be caused by Escherichia coli, which house flies can transmit. Moringa oleifera leaves have antimicrobial substances such as flavonoids, triterpenoids, steroids, saponins and tannins. This aim of the study was to determine the minimum inhibitory concentration of M. oleifera infusion on the growth of E. coli. This research is a laboratory experiment with Well Diffusion Agar method and dilution technique. The materials used in the study were M. oleifera leaf infusion with concentrations of 50%, 40%, 30%, 20%, and 10%, while 0% was a negative control (Aquadest). E. coli isolates were obtained from M. domestica. The results showed that the inhibition zone formed at concentrations of 50%, 40%, 30%, 20%, 10%, and 0% was 15.55 mm, 13.80 mm, 13.10 mm, 10.10 mm, and 0 mm, respectively. The minimum inhibitory concentration of leaf infusion against E. coli isolates was 25%, and the minimum bactericidal concentration could not be determined because all concentrations tested showed bacterial growth. Instead, the lowest inhibitory concentration was 25%. In concentrations of 50%, 40%, and 30%, M. oleifera leaf infusion has potent antibacterial action; at concentrations of 20%, it has moderate antimicrobial activity; and at concentrations of 10%, it is unable to inhibit the growth of E. coli. Further research is needed to determine the value of the minimum bactericidal concentration at concentrations above 25%, and it is necessary to test it on other digestive tract pathogenic bacteria.