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Group B Streptococcus is a gram-positive coccal bacterium which produces an arrow zone of blood hemolysis on blood agar. Group B Streptococcus is the most common cause of invasive bacterial illness in neonates, including sepsis, meningitis, septicemia, and pneumonia. For the first time, such a study of Streptococcus agalactiae has been conducted in hospitals of Anbar Governorate .All Streptococcus agalactiae identified by conventianal methods , automated methods using Vitek-2 system , and molecular methods by conventional PCR. All isolates gave a positive result as 16S rRNA. Distribution of resistance ratio for Streptococcus agalactiae were Penicillin 20% , Clindamycin 68% , Chloramphenicol % 46 , Tetracycline 82% , Erythromycin % 100 ,Imipenem % 12 , and Ciprofloxacillin 26.47%. The Cyl E and bibA genes were detected by conventional PCR and the result showed (72%) strains positive, but in case of bla Cyl E gene (53.48%) of strains harbored bla bibA genes , while 48.83 of Streptococcus agalactiae contain Spb1 gene . This approach showed the coexistence of bla Cyl E , Spb 1 and bibA genes in 48.83% strains of Streptococcus agalactiae.

This research was directed to understand the bactericidal effect of epidermal mucus of two Asian cat fish species viz. Clarias batrachus and Heteropneustes fossilis. Epidermal mucus extracts (raw and diluted) of both cat fish species were tested against several Gram negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, A. hydrophila) and Gram positive bacterial strains (Bacillius cereus, Staphylococcus aureus, S. epidermidis) and antibacterial results were also compared with two standard antibiotics viz. amikacin and chloramphenicol used as positive control. An A. hydrophila challenge experiment was also performed on all selected test fish species to examine the change in the amount of mucus production and its bactericidal impact.. Both epidermal mucus extracts (raw and diluted) of all selected normal and bacterial challenged test objects showed potent bactericidal effect against all pathogenic bacterial strains taken under study. However, former was more effective than later. Also raw epidermal mucus extracts of both normal and bacterial challenged cat fish species exhibited significantly higher ZOI values against all selected microbial strains than diluted mucus extracts and antibiotic chloramphenicol. Hence, these outcomes have clearly revealed that this cost effective natural product acquired from fishes is the key component of their defensive system. Therefore, it could be utilized as a novel ‘antimicrobial’ in human as well as veterinary sector for combating against several bacterial diseases.

To determinate the antimicrobial effect of chloramphenicol and aqueous extract against multidrug-resistant enterohemorrhagic Escherichia coli (EHEC) and Salmonella enterica serovar Typhimurium in C...

Salmonella is one of the major causes of food-borne infections. We investigated the serotype distribution and antimicrobial resistance of Salmonella isolates collected in Korea between January 2016 and December 2017. In total, 669 Salmonella isolates were collected from clinical specimens at 19 university hospitals. Serotyping was performed according to the Kauffmann-White scheme, and antimicrobial susceptibility was tested using Sensititre EUVSEC plates or disk diffusion. Among the strains, C (39.8%) and B (36.6%) were the most prevalent serogroups. In total, 51 serotypes were identified, and common serotypes were S. enterica serovar I 4,[5],12:i:- (16.7%), S. Enteritidis (16.1%), S. Bareilly (14.6%), S. Typhimurium (9.9%), and S. Infantis (6.9%). The resistance rates to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole were 32.6%, 12.1%, and 8.4%, respectively. The resistance rates to cefotaxime and ciprofloxacin were 8.1% and 3.0%, respectively, while 5.4% were multidrug-resistant. S. enterica serovar I 4,[5],12:i:- and S. Enteritidis were highly prevalent, and there was an increase in rare serotypes. Multidrug resistance and ciprofloxacin resistance were highly prevalent. Periodic investigations of Salmonella serotypes and antimicrobial resistance are needed.

The ingestion and digestion of Escherichia coli by the ciliated protozoan, Tetrahymena thermophila, was investigated after an initial exposure to either water-soluble single-walled carbon nanotubes (SWNT) or to carbon black (CB). Both SWNT and CB were internalised and visible in food vacuoles of ciliates. When presented with E. coli expressing green-fluorescent protein (GFP), these ciliates internalised bacteria as well. However, ciliates that had first internalised SWNT but not CB subsequently externalised or egested vesicle-like structures with fluorescent bacteria inside. These egested bacteria were viable and less susceptible than planktonic E. coli to killing either by the antibiotic, chloramphenicol or the disinfectant, glutaraldehyde. These results suggest that SWNT can alter the intracellular trafficking of vesicles within ciliates, leading to bacterial prey being packaged externally and protected for a time from environmental killing, which could have implications for sewage treatment and for public health.

Murray-Darling Freshwater Research CentreMDFRC item.The antibiotic resistance of bacteria from the water column of various rivers and billabongs in north-eastern Victoria was studied during 1988-91. Two indices were used as measures of resistance: conventional disc-sensitivity tests with culturable bacteria, and the effect of antibiotics on the uptake of 14C-glucose and 14C-amino acids by native bacterial assemblages. Culturable bacteria were resistant to ampicillin, methicillin and penicillin but generally sensitive to nalidixic acid, neomycin, streptomycin, sulfafurazole and tetracycline. Responses to chloramphenicol, erythromycin, nitrofurantoin and sulfamethizole were variable. Bacteria isolated from rivers were more resistant to antibiotics than were those isolated from billabongs. Methicillin, even at 200 mg L-1, had little effect on the uptake of 14C-labelled compounds. Nalidic acid (20 mg L-1) also was ineffective unless lengthy pre-incubations (24 h) were used. Chloramphenicol and tetracycline at 20 mg L-1 markedly reduced amino acid uptake but not glucose uptake. The widespread antibiotic resistance of aquatic bacteria casts doubt on the suitability of these compounds to selectively inhibit the prokaryotic component in ecological studies and may be cause for concern regarding the spread of antibiotic resistance through natural aquatic communities.

Objectives The mobile tigecycline resistance gene tet(X4), conferring resistance to all tetracyclines, is largely reported from China, however the global spread of such a novel resistance mechanism is a concern for preserving the efficacy of these last-resort antibiotics. The aim of our study was to determine the genetic basis of resistance in a tigecycline-resistant Escherichia coli strain (2-326) isolated from sewage in Bergen, Norway, using whole-genome sequencing (WGS). Methods WGS was carried out using Illumina MiSeq-based sequencing. In vitro conjugation assays were performed to determine the potential of isolate 2-326 to transfer tigecycline resistance to other strains. Results Escherichia coli isolate 2-326 belongs to pathogenic sequence type 167 (ST167) and carries several clinically important antibiotic resistance genes including tet(X4), blaCTX-M-14, dfrA12, sul2, qnrS1 as well as several aminoglycoside resistance genes. Tigecycline resistance along with resistance to tetracycline, sulfamethoxazole, chloramphenicol and azithromycin was transferred to green fluorescent protein (GFP)-encoding E. coli strain CV601-GFP by conjugation. Conclusion To the best of our knowledge, this is the first report of E. coli carrying mobile tet(X4) gene from Norway. Our study demonstrates the ongoing spread of new mechanisms of resistance against last-resort antibiotics and the need for surveillance of such resistance factors in the population in order to mitigate their spread.

Background: To develop other H2O2-based approaches for the efficient degradation of chloramphenicol, this study elucidates the performance of the nZVC/H2O2 process in the degradation of chloramphenicol in water. Methods: A rotating packed bed (RPB) with blade packings was adopted in the mass-production of nanoscale zero-valent copper (RPB-nZVC). The effects of pH, initial chloramphenicol concentration, nZVC dosage, and H2O2 concentration on the degradation of chloramphenicol using the nZVC/H2O2 process with RPB-nZVC were studied. Significant findings: The results reveal that the optimal nZVC dosage and H2O2 concentration were 250 mg/L and 1.25 mmol/L, respectively. At pH 3 with an initial chloramphenicol concentration of 10 mg/L, an nZVC dosage of 250 mg/L, an H2O2 concentration of 1.25 mmol/L, and a degradation time of 30 min, the nZVC/H2O2 process with the RPB-nZVC degraded 93% of the chloramphenicol. However, at the same operating parameters, the efficiency of degradation of chloramphenicol of 63% was achieved in the nZVC/H2O2 process with commercial nZVC that was obtained from Sigma-Aldrich. Therefore, the nZVC/H2O2 process with RPB-nZVC can be used to degrade strongly chloramphenicol in water.

This study aimed to determine the effectiveness of antibacterial formulations derived from herbal plants against mastitis-causing bacteria in dairy cattle. Herbal extracts composed of betel leaves extract, kecombrang flower extract, and turmeric extract were tested against Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli. The research was carried out in a Completely Randomized Design (CRD) using ten treatments and four replications at the Laboratory of Research and Testing, Faculty of Animal Husbandry, Padjadjaran University. The results showed that herbal antibacterial formulations could inhibit the growth of Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli bacteria. The most inhibitory power was obtained from P8 treatment (50% betel leaves + 50% kecombrang flower + 50% turmeric) categorized in "strong inhibition." The percentage of antibacterial inhibition of P8 formulation compared to chloramphenicol was 32% against Staphylococcus aureus, 33% against Streptococcus agalactiae, and 31% against Escherichia coli. Conclusively, the best herbal antibacterial formulation was a combination of 50% betel leaves extract, 50% kecombrang flower extract, and 50% turmeric extract.

The purpose of this study was to evaluate the probiotic characteristics and safety and to study the antifungal activity of C. amycolatum ICIS 9 and C. amycolatum ICIS 53 against Candida spp. The probiotic potential and safety properties were assessed by standard parameters. Both strains showed good survival at pH 3 for 3 h and high tolerance to 0.3% bile salts after 4 h of incubation. The indicators of hydrophobicity, autoaggregation, and surface tension for ICIS 9 were 89.43% (n-hexane) and 73.96% (xylene) and ranged from 13.13 to 39.86% and 34.27 mN/m, respectively. For ICIS 53, they were 59.95% (n-hexane) and 45.68% (xylene), from 35.58 to 51.53% and 32.40 mN/m, respectively. The strains ICIS 9 and ICIS 53 exhibited varying levels of coaggregation with all eight examined bacterial pathogens. The ICIS 9 strain was resistant to amikacin, amoxicillin, clarithromycin, chloramphenicol, ciprofloxacin, and gentamycin. ICIS 53 was resistant only to ciprofloxacin. The cell-free supernatant of strains ICIS 9 and ICIS 53 showed good antimicrobial and antibiofilm activity against 10 pathogenic vaginal and intestinal isolates of Candida spp. The CFS of ICIS 9 was more active against intestinal isolates, and the CFS of ICIS 53 showed good antimicrobial activity against vaginal isolates while inhibiting the growth of 2 out of 5 Candida spp. isolated from the intestine. Both of the strains were capable of reducing the biofilm formation of Candida fungi. In the case of the vaginal isolates of C. krusei V1, the results showed that the inhibition levels of ICIS 9 and ICIS 53 were 36.75 and 11.4%, respectively. In the case of C. albicans (V2, V3, V7, and V8), the inhibition of biofilm formation was no more than 7.07%. ICIS 9 and ICIS 53 also significantly inhibited biofilm formation of C. krusei 2613 intestinal isolates by 42.75 and 41.87%, respectively, with ICIS 9 inhibiting biofilm formation of C. albicans (2607, 2311, 2615, and 2615) from 3.38 to 15.69% and ICIS 53 from 5.95 to 23.48%. None of the strains showed DNase, haemolytic, or gelatinase activities. The results obtained revealed that ICIS 9 and ICIS 53 have safe properties and have the potential to be developed as probiotics.

Highlights • Lactic acid bacteria associated with medicinal plants show beneficial health properties. • Among all isolates, 25% are safe for human consumption. • Best anti-bacterial, anti-oxidant, activities have been shown by Lactobacillus agilis. • Lactobacillus agilis has been found to have anti-diabetic and anti-inflammatory properties., Potential probiotic bacteria can be used as a biotherapeutic agent and a sustainable alternative to antibiotics, as an anti-oxidative, anti-inflammatory, and anti-diabetic agent without causing any serious side effects. Mostly human-friendly Lactic acid bacteria (LAB) have been isolated from the animal-human origin to be used as biotherapeutic agents or to produce useful metabolites (nutraceutical). However, less information is known about the role of medicinal plants associated LAB as biotherapeutic agents. The isolation of 115 human-friendly Lactobacillus strains was done from the rhizosphere of the medicinal plants Ocimum tenuiflorum, Azadirachta indica, Ficus carica. The obtained bacteria were then tested for their safe status before being using it for a beneficial purpose. Out of 115 strains, 29 (25%) were negative for blood hemolytic activities. Among these 29 isolates, three isolates did not show a breakdown of gelatin and were recognized as safe. Antibiotic resistance assay showed resistance of two of them against antibiotics discs of Streptomycin (10 µg), Ciprofloxacin (20 µg), Vancomycin (30 µg), Metronidazole (10 µg), Ampicillin (5 µg), Chloramphenicol (30 µg), Kanamycin (30 µg), Erythromycin (15 µg), Penicillin (10 µg) and Tetracycline (30 µg). The bacterial isolate (T-2) was found safe that was identified as Lactobacillus agilis by sequence analysis of 16 s rRNA gene and processed in vitro as an anti-bacterial, anti-oxidant, anti-diabetic, and anti-inflammatory agent. Free radical scavenging activities and inhibition of α-amylase activities for Lactobacillus agilis were found relative to standard drug values as 68% and 73% and 51.3% and 65.3%, respectively. The in-vitro anti-inflammatory assay showed 61.6% (Lactobacillus agilis) while showed 69% (aspirin) activity for denaturation albumin protein. The results suggested that Lactobacillus agilis can be used as a potential probiotic strain as well as can be used to produce nutraceuticals.

The aptamer domain of the theophylline riboswitch was randomized to generate a library containing millions of different variants. Dual genetic selection utilizing the cat-upp fusion gene was performed for the library, which successfully led to the identification of a caffeine-specific synthetic riboswitch. When a chloramphenicol-resistance gene was expressed under control of this riboswitch, E. coli cells showed chloramphenicol resistance only in the presence of caffeine. When inserted upstream of the gfpuv or lacZ gene, the caffeine riboswitch induced the expression of green fluorescent protein or β-galactosidase in the presence of caffeine, respectively. When tested with various concentrations of caffeine, the β-galactosidase activity was proportional to the amount of caffeine, clearly indicating the caffeine-dependent gene regulation by the caffeine riboswitch.

The biochemical implication of chloramphenicol-induced lymphoma and the ameliorative potential ofJusticiacarneaandCnidoscolusaconitifoliuson male Wistar rats were evaluated in this study. Seventy (70) male Wistar rats with average body weights of 128g were randomly grouped into 14 of 5 rats each. Group 1 received commercial rat feed and waterad libitum.Rats in groups 2-14 were given 250mg/kg bodyweight of chloramphenicol by oral intubation for 28 days. Results of blood samples collected after 28 days from all the groups showed normal blood film in Group 1 and abnormal increases and lymphocytes and the presence of blast cells in Groups 2-14. Group 2 did not receive any treatment and is referred to as the negative control. The remaining groups (3-14) were administered with aqueous leaf extracts ofJ.carnea(Groups 3-6),C.aconitifolius(Groups 7-10), and a combination of both extracts (Groups 11-14) in doses of 500mg/kg, 1000mg/kg, 1500mg/kg and 2000mg/kg respectively, for 28 days. Data obtained showed that lymphocytes were elevated (pJ.carneaandC.aconitifoliuswas able to ameliorate the chloramphenicol-induced lymphoma better than the single therapy of each extract. The result of the investigation supports the earlier findings that chloramphenicol could cause acute lymphocytic leukemia. It further provides evidence that combined extracts ofJ.carneaandC.aconitifoliusmay have an ameliorative effect in blood diseases connected to over-exposure to chloramphenicol.

One of the infectious diseases that occur in the oral cavity is dental caries (cavities). The bacteria that play a role in the occurrence of infection are Streptococcus mutans bacteria, and the matoa plant is one of the plants that can act as antibacterial (Pometia pinnata J.R Forst) which has high efficacious compounds. This study aimed to determine the activity and potency of the ethanolic extract of matoa fruit peel (Pometia pinnata J.R Forst & G. Forst) against Streptococcus mutans bacteria. This research is a laboratory experimental research. Matoa fruit peel simplicia was extracted by maceration method with 96% ethanol solvent, then tested for phytochemical screening to determine the class of compounds contained in the matoa fruit peel. Furthermore, the activity was tested against Streptococcus mutans bacteria using a positive control of chloramphenicol antibiotics and a negative control of Dimethyl Sulfoxide. After that, the values of the Minimum Inhibitory Level and Minimum Killer were measured. From these results, it was continued to test the antibacterial potential using the Kirby Bauer method. The results showed that the ethanol extract of matoa fruit peel (Pometia pinnata J.R Forst & G. Forst) had activity against Streptococcus mutans bacteria. The potential value of the matoa fruit peel extract against Streptococcus mutans bacteria at concentrations of 25%, 50% and 75%, respectively, was 11.75 mm, 15.82 mm and 18.75 mm which was included in the category of strong inhibition.

Glutathione s-transferases(GSTs) are enzymes involved in the conjugation and deactivation of various xenobiotics including drugs. Thisin-silico study was undertaken in order to investigate the interaction between beta-class glutathione s-transferase and five selected antibiotics, namely; ampicillin, tetracycline, chloramphenicol, ciprofloxacin and cephalexin using molecular docking study. RaptorX server was used to predict the amino acids involved at the binding sitewhile molecular docking study was employed in order to investigate the binding interactions.RaptorX predicted several amino acids which were different from the ones observed in molecular docking because of the variability in the substrate binding site of GSTs however, all the amino acids predicted by RaptorX were also found to be involved in the GSH binding.Lys107, Phe109, Ser110, Leu113, Trp114, His115 and Arg123, Leu168 were the amino acids involved in the binding of various antibiotics to the substrate binding site of the protein while Ala9, Cys10, Leu32, Tyr51, Val52, Pro53, Glu65 and Ala66were involved in the binding of the co-substrate GSH to the binding site of the protein. The results indicated that all the antibiotics showed a good binding affinity with the beta class GST and are therefore capable of deactivating the drugs. With these, finding a beta class GST inhibitors alongside antibiotics during a treatment of diseases will be of beneficial in the current fight against antibiotic resistance.

Dayak onions (Eleutherine palmifolia (L.) Merr.) Is one of the natural ingredients which is often used for medicine in Kalimantan. E. palmifolia used for treatment because it contains secondary metabolite compounds that have potential as antibacterial. Such as phenolic compounds, flavonoids, alkaloids, saponins, tannins and glycosides which are included in polar compounds. This study aims to determine the effect of ethanol extract 70% E. palmifolia against bacteria Salmonella paratyphi with the extraction method maceration. S. paratyphi is a bacterial pathogen against humans whose habitat is in the digestive tract. This research was conducted to test the extract's antibacterial activity with gradient concentration of 20 mg / mL, 30 mg / mL, 40 mg / mL, 50 mg / mL, and 60 mg / mL and chloramphenicol as a positive control and sterile aquadest as a negative control. The antibacterial test method used is diffusion method with 5 repetitions. Our results showed that E. palmifolia extract could inhibit S. paratyphi growth as evidenced by the presence of an inhibition zone that is formed around paper disk on media with concentration 20 mg / mL, 30 mg / mL, 40 mg / mL, 50 mg / mL, and 60 mg / mL. Where the average diameter of the inhibition zone was 6.6 mm, 7.4 mm, 8.8 mm, 9.9 mm, respectively fall into the category of ineffective inhibition and 11 mm is in the weak category. Based on the research that has been done, it was found that there was an effect of giving E. palmifolia extract on the growth of S. paratyphi bacteria but there was no significant difference based on the one way ANOVA test.

Salmonella is considered one of the leading causes for foodborne diseases in humans. Pork and its products contaminated with Salmonella are increasingly recognized as an important source of human salmonellosis. The aim of this study was to investigate the antimicrobial resistance and prevalence of integrons in Salmonella isolates from pig farms. In total, 92 of 724 (12.7%) samples were Salmonella-positive, including 64 (15.0%) from fecal samples, 27 (12.6%) from floor samples, 1 (4.5%) from water samples, and 0 from feed and air samples. These isolates showed the highest resistance to tetracycline (85.9%), followed by trimethoprim (67.4%), ampicillin (60.9%), and chloramphenicol (51.1%). In addition, 51 isolates carried the complete class 1 integron, most of which (42/51) harbored antibiotic resistance cassettes. A total of six gene cassettes including orfF, est-X, dfrA1+aadA1, aadA1, dfrA12+aadA2, and sat were identified, in which the most prevalent one was orfF (29.4%). Furthermore, all 19 class 1 integron-positive isolates harboring dfr genes showed resistance to trimethoprim (SXT), suggesting that the trimethoprim resistance gene (dfr) may contribute to the emergence of SXT resistance phenotype. Therefore, considering the significance of integrons and related resistance genes for public health, special measures should be taken to control Salmonella spp. on the pig farms and to prevent spread of integrons and associated resistance genes.

Purpose This study set out to determine the antimicrobial resistance trends of Haemophilus influenzae isolates from pediatric hospitals in Mainland China, which would provide basis for clinical treatment. Methods The Infectious Disease Surveillance of Pediatrics (ISPED) collaboration group conducted this study. H. influenzae strains isolated from nine pediatric hospitals in Mainland China were included. Disk diffusion method was used for antimicrobial susceptibility test. Cefinase disc was used for detection of β-lactamase. Results In total, 13810 H. influenzae isolates were included during 2017–2019: 93.17% of which were from respiratory tract specimens, 4.63% from vaginal swabs, 1.10% from secretion, and 1.10% from others. Of all strains, 63.32% isolates produced β-lactamase; 8.22% isolates were β-lactamase-negative and ampicillin-resistant (BLNAR). The resistance to sulfamethoxazole-trimethoprim was 70.98%, followed by resistance to ampicillin (69.37%), cefuroxime (51.35%), ampicillin-sulbactam (38.82%), azithromycin (38.21%), amoxicillin-clavulanate (35.28%). More than 90% of H. influenzae isolates were susceptible to ceftriaxone, cefotaxime, meropenem, levofloxacin and chloramphenicol. The resistance rate of ampicillin and azithromycin in H. influenzae showed an increasing trend through the years. Statistically significant differences in antibiotic-resistance rates of all the antibiotics except chloramphenicol were found in different regions. The major Multi-Drug Resistance pattern was resistant to β-lactams, macrolides, and sulfonamides. Conclusions There is a rising trend of resistance rate of ampicillin and azithromycin in H. influenzae. Antimicrobial resistance of H. influenzae deserves our ongoing attention. Third-generation cephalosporin could be the preferred treatment option of infections caused by ampicillin-resistant H. influenzae.

A clinically isolated pan-resistant Klebsiella pneumoniae strain (ST11), KPN142 was subjected to whole-genome sequencing. Genomic sequence of KPN142 showed that limited antibiotic resistances (β-lactams [blashv-11], sulfonamides [sul1 and dfrA22], bacitracin [bacA], tetracycline [tet34], aminoglycosides [ksgA, kdpE, aph(3)Ia, aac(3)III, and ant(3)Ia], and chloramphenicol [catA1]) were mediated by enzymes, and efflux pumps contributed most to pan resistance. Five types of multidrug resistance efflux pump families were identified, including the resistance nodulation division superfamily (AcrAB-TolC, AcrD, MdtABC, and KexD), the ATP-binding cascade superfamily (MacAB), the small multidrug resistance family (KpnEF), the multidrug and toxic compound extrusion family (KdeA), and the major facilitator superfamily (EmrAB). There was an AcrAB-TolC efflux pump system, and inhibitory regulatory gene acrR and ramR of system carried deletion mutation, which lead to overexpression of AcrAB-TolC efflux pump, and in turn plays key role in the pan resistance of KPN142. Moreover, we did not find mgrb, a suppressor in the expression of phoPQ, overexpression of which may confer the resistance of KPN142 to colistin B. In addition, K. pneumoniae KPN142 carries IS1, IS3, and IntI1, which means that KPN142 is able to transfer drug-resistance genes. Of note, we detected the overexpression of acrB, ramA, phoP, and phoQ by real-time quantitative reverse transcription-polymerase chain reaction, and carbonyl cyanide chlorophenylhydrazone was able to reverse the resistance patterns of K. pneumoniae KPN142. In conclusion, we consider that the overexpression of AcrAB-TolC efflux pump mediates the resistance to most common clinical antimicrobial agents, and the overexpression of phoPQ mediates the resistance to colistin B in K. pneumoniae KPN142.

A total of 220 birds of age ranging from 3 to 14 weeks old were collected from several backyards and different farms in Sharkia Governorate, Egypt, and surveyed for the presence of fowl cholera. Twenty Pasteurella multocida from chickens (15/145, 10%) and ducks (5/75, 6%) were bacteriologically isolated, and it was shown that the infection was significantly related to age and breed. Capsular typing, using multiplex polymerase chain reaction (PCR), demonstrated that all strains were type A (100%). Disk diffusion assay towards ten antimicrobials revealed high susceptibilities to amikacin, doxycycline, chloramphenicol, and neomycin with varying degrees. Doxycycline was effective at the lowest concentration (MIC 0.125–1 µg/ml). Multidrug resistance was detected with a percentage of 25%. Multidrug-resistant isolates (five isolates) were subjected to study their pathogenicity in embryonated chicken eggs (ECE). The results showed a variation in indices between different dilutions of the tested strains. The resulting pathogenicity indices showed significant differences (P

Antibiotic resistance has become a major threat to human health around the world, but its spread through the aquatic environment has been often overlooked. This study aimed to determine the occurrence of vancomycin-resistant Staphylococcus aureus in hospital wastewaters and their transmission into public water bodies in Kerala, India. A total of 113 S. aureus were isolated from three hospital effluents in Kerala, India. Standard disc diffusion and the strip method were used for antibiotic susceptibility testing and minimum inhibitory concentration detection. Plasmid-mediated vancomycin resistance was confirmed by plasmid curing and conjugation; resistant genes were detected by the polymerase chain reaction (PCR). Nearly 76% of S. aureus isolates were resistant to β-lactams, chloramphenicol, macrolides, aminoglycosides, and glycopeptide class of antibiotics. Among the vancomycin-resistant Staphylococcus aureus (VRSA) isolates, the prevalence rates of vanA and vanB resistance-encoding genes were 46.5 and 59.3%, respectively. Through the broth mating method, vanA gene was successfully transferred from VRSA donor to vancomycin-sensitive S. aureus. The study strongly indicates the contamination of water bodies with antibiotic-resistant bacteria from hospital discharges, their dissemination and possible transfer to microbes in the aquatic environment, posing a serious threat for public health. HIGHLIGHTS High vancomycin resistance was observed in S. aureus isolates in the hospital effluent.; Vancomycin-resistant Staphylococcus aureus (VRSA) isolates with vanA and vanB resistance-encoding genes have a higher chance of surviving in the sewage treatment plants.; Horizontal transfer of the resistance gene was confirmed by conjugation.; The VRSA isolates have a strong capacity to acquire or transfer antibiotic-resistant genes, posing a threat to public health.

The PbO2 -2 wt.% sodium dodecyl sulfate composite formed from methanesulfonate electrolyte consists of 93.1% of α-phase PbO2 in contrast to the similar one synthesized from nitrate electrolyte, which contains 73.3% of β phase. The electrocatalytic activity of the obtained composites in the oxygen evolution reaction and oxidation of chloramphenicol was investigated. It was found that the Tafel slope significantly exceeds the theoretical value, which indicates a decrease in the degree of filling of the electrode surface with oxygen-containing particles. In the presence of organic compound and chloride ions in the solution, irreversible adsorption of the intermediate is observed, which leads to additional blocking of active centers on the oxide surface, which are involved in the oxidation of organic substance. It was established that the maximum rate of chloramphenicol conversion is 83.5% and 85% at 50 and 80 mA cm-2 , respectively, under kinetic control. The heterogeneous oxidation rate constant of chloramphenicol is 0.0035 min-1 . Oxidation of chloramphenicol occurs through the formation of 4-(-2-amino-1,3-dihydroxy-propanyl)-nitrobenzene with cleavage of dichloroacetic acid. Next, the amino group is oxidized to the nitro group to form 4-(2-nitro-1,3-dihydroxy-propanyl)-nitrobenzene. Subsequent electrolysis produces nitrobenzoic acid, which is oxidized to benzoic acid, later hydroquinone, then benzoquinone and a set of aliphatic compounds. PRACTITIONER POINTS: The PbO2 -2 wt.% SDS composite consists of 93.1% of α phase of PbO2 in contrast to those synthesized from nitrate electrolyte. The Tafel slope indicates a decrease of surface filling with oxygen-containing particles. Irreversible adsorption of the intermediate is observed in the presence of chloride ions.

Objectives We sequenced two IncA/C plasmids harbouring blaCTX-M-2 in Klebsiella pneumoniae clinical isolates and compared their antibiotic resistance islands. Methods Transconjugants were obtained from two clinical K. pneumoniae isolates harbouring blaCTX-M-2. Plasmid DNA from transconjugants underwent short-read whole-genome sequencing, reads were assembled, and gaps were closed by PCR and sequencing. Determination of plasmid replicons, antibiotic resistance genes, identification and characterisation of insertion sequence (IS) elements, and comparison with publicly available plasmid sequences were performed. Results blaCTX-M-2 was located in a complex class 1 integron In35::ISCR1::blaCTX-M-2, inserted in two different transposons designated Tn7057 and Tn7058, that reside in the resistance islands of plasmids pUR-KP0923 and pUR-KP1025, respectively. The general modules of both transposons were In35::ISCR1::blaCTX-M-2–Tn1000-like–Tn2*–ISKpn11-12-13 variable module–ΔTn21. In Tn7057 there was ΔIS10R–catA2 associated with an additional ISKpn13. Both plasmids belonged to IncC type 2 and ST3. pUR-KP0923 was 167 138 bp in length and had a 37 926-bp resistance island at position 4 (RI-4). Plasmid pUR-KP1025 was 168 128 bp with a RI-4 of 36 222 bp. Conclusion This report describes the molecular nature of two transposons (Tn7057 and Tn7058) harbouring blaCTX-M-2 that reside in IncC type 2 ST3 plasmids. These transposons mediate resistance to oxyimino-cephalosporins, gentamicin and, in the case of Tn7057, chloramphenicol. CTX-M-2 is an important extended-spectrum β-lactamase (ESBL) to South American epidemiology. It is remarkable that despite being only two plasmid sequences, the information revealed here could contribute to a better understanding of the resistance islands from IncC type 2 plasmids.

Staphylococcal and streptococcal species trigger a wide variety of infections involving epithelial tissues. Virginian witch hazel (WH; Hamamelis virginiana L.; family: Hamamelidaceae) is a plant that has been used traditionally by Native Americans to treat a variety of skin conditions. Extracts from the leaves were examined for their inhibitory effects on these bacterial species. Solvents of different polarity (water, methanol, ethyl acetate, hexane and chloroform) were used to prepare extracts from WH leaves, and the aqueous resuspensions were screened for antibacterial activities using disc diffusion and liquid dilution assays. Extract phytochemical profiles and toxicities were also examined, and combinations of extracts with conventional antibiotics were tested against each bacterial strain. The methanolic and aqueous extracts inhibited the growth of S. oralis, S. pyogenes, S. epidermidis and S. aureus, but not S. mutans. The extracts were especially active against staphylococcal species, with MIC values between 200 and 500 μg/ml. Combinations of active extracts with conventional antibiotics failed to yield beneficial interactions, except for two cases where additive interactions were observed (aqueous WH extract combined with chloramphenicol against S. oralis, and methanolic WH extract combined with ciprofloxacin against S. aureus). Phytochemical assays indicated an abundance of tannins, triterpenoids and phenolics in the water and methanol extracts, with trace amounts of these components in the ethyl acetate extract. Phytochemicals were not detected in hexane and chloroform extracts. Thus, phytochemical abundance in extracts was concordant with antibacterial activities. All extracts were found to be non-toxic in Artemia nauplii assays. These findings indicate the potential for WH leaf extracts for clinical use in treating staphylococcal and streptococcal infections, while substantiating their traditional Native American uses.

A major current problem in public health is the issue of antimicrobial resistance of Escherichia coli in humans and poultry. In Indonesia, multidrug-resistant E. coli are of specific concern since such E. coli may cause public health problems in humans. The prevalence of multidrug-resistant chicken E. coli strains and the E. coli resistance genes, which are tet(A) and tet(B) genes, were investigated in the present study. A total of 57 swabs were collected from layer and broiler breeder farms in West Java, Indonesia, and used in the experiment. Eighteen isolates were identified as E. coli by the disk diffusion method. The isolates classified as drug-resistant and intermediate were then identified using PCR for the antimicrobial resistance genes. The results showed that 18 isolates of E. coli from layer-breeder and broiler-breeder farms in West Java were resistant to ampicillin (100%), nalidixic acid (94%), tetracycline (88%), oxytetracycline (83%), gentamicin (27%), and chloramphenicol (22%). PCR identification of E. coli antimicrobial-resistant genes in 18 isolates showed tet(A) and tet(B) genes. This study reports antimicrobial resistance genes among E. coli on layer and broiler breeder farms in West Java. This present study showed that E. coli isolated from layers-breeder and broiler-breeder farms in West Java of Indonesia carried tet(A) and tet(B) genes, the multidrug-resistance genes.

Cockroaches (Periplaneta americana) are known to have potential as vectors of various pathogenic bacteria in various locations including the nutrition department area in the hospitals. Research related to the role of these animals as vectors of pathogenic bacteria has not been done. The provision of food in the hospital nutrition department has the potential for bacterial contamination from food, equipment, hospital staff, and the environment. Cockroaches can be a vector for spreading various nosocomial infectious diseases in hospitals. A descriptive method was used, and the data were obtained by bacterial isolation, Gram staining method, antibiotic sensitivity test, and bacterial identification using Microbact system software 2000. This study was carried out at the Biology Education Laboratory, Education and Teacher Training Faculty, Tadulako University. Based on the results of the study, 6 species of bacterial isolates from cockroach feet  in the nutrition department area of Palu city hospital, namely E. coli, S. arizonae, Salmonella sp., K. ozaenae, S. simulans, and S. enterica. Antibiotic sensitivity test showed that four bacteria exhibited multi-drug resistance to antibiotics Amoxycillin, Chloramphenicol and Vancomycin. Meanwhile,S. enterica was still sensitive to the five tested antibiotics namely Amoxycillin, Chloramphenicol, Ciprofloxacin, Ofloxacin, and Vancomycin. serious policies and handling are needed to control new types of vectors that carry diseases in humans.. meanwhile,S. entericawas still sensitive to the five tested antibiotics.

Highly sensitive and rapid detection of chloramphenicol antibiotics (CAPs) in aquatic products via lateral flow immunoassay (LFA) strips remains challenging. This study developed a surface-enhanced Raman scattering (SERS)–based LFA strip for ultrasensitive analysis of CAPs by using noble metal nanoparticles (NPs). A kind of core–shell Au@Ag NPs were employed to prepare SERS tags considering the stability and repeatability. In order to obtain higher stability and repeatability, we designed antibody-modified gold@silver core–shell nanoparticles (Au@Ag NPs) as SERS nanotags for quantitative Raman detection of the target in the LFA strip. Results showed that SERS-based LFA strip allowed quantified analysis of chloramphenicol (CAP), thiamphenicol (TAP), and florfenicol (FFC) with the limits of detection of 0.36 ng/mL, 0.20 ng/mL, and 0.78 ng/mL, respectively. Furthermore, SERS-based LFA strip exhibited favorable sensitivity (IC50 values of CAP, TAP, and FFC were 12.94 ng/mL, 8.76 ng/mL, and 12.22 ng/mL, respectively). This SERS-based LFA strip was finally applied in the detection of CAP in chub and the recovery was 91.5 to 106.4%. This SERS-based LFA strip could be used as an effective tool for detecting CAPs in aquatic products.

Latar Belakang: Penyakit infeksi masih merupakan salah satu masalah kesehatan di dunia, termasuk Indonesia. Untuk penanggulangan penyakit infeksi telah banyak digunakan berbagai jenis antibiotika. Salah satu contoh penyakit infeksi yang disebabkan oleh mikroorganisme adalah demam tifoid atau demam enterik yang disebabkan Salmonella typhi (S.typhi.). Sejak tahun 1948 kloramfenikol merupakan drug of choice (obat terpilih) untuk infeksi S.typhi. Tujuan: Untuk membandingkan dan mengetahui potensi antibiotika dari kloramfenikol dan amoksisilin terhadap S.typhi. Diperlukan penelitian untuk menemukan terapi antibiotika pilihan lain yang lebih sensitif. Salah satunya dengan melakukan penelitian ini dengan uji KHM dan KBM. Metode: Untuk melihat potensi antibiotika dilakukan pengujian Konsentrasi Hambat Minimum (KHM) dengan metode pengenceran tabung (tube dilution method) dan Konsentrasi Bunuh Minimum (KBM) menggunakan metode Kirby Bauer. Penelitian ini merupakan jenis penelitian eksperimen laboratorium secara in vitro. Analisis data menggunakan aplikasi SPSS dengan Mann Whitney U Test.Hasil: Penelitian menunjukkan bahwa kloramfenikol memiliki potensi antibotika dengan nilai KHM sebesar 12,50 µg/ml, sedangkan amoksisilin memiliki potensi antibiotika dengan nilai KHM sebesar 6,25 µg/ml. Untuk nilai KBM kloramfenikol dan amoksisilin memiliki nilai yang sama sebesar 25 µg/ml. Kesimpulan: Tidak terdapat perbedaan nilai KHM dan KBM antara antibiotika kloramfenikol dan amoksisilin terhadap S.typhi. Amoksisilin dapat digunakan sebagai salah satu obat alternatif untuk terapi infeksi demam tifoid.

The aim of the work was to design and carry out experimental studies of a set of reagents to identify the spectrum of genes that determine the resistance of the Vibrio cholerae strains to antibacterial drugs.Materials and methods. V. cholerae strains isolated from humans and environmental objects during epidemiological complications and the cholera-free period were included in the study. Sensitivity to antimicrobial drugs was evaluated by the disk diffusion method. Whole genome sequencing was performed on an Illumina MiSeq. The profile of resistance genes was determined based on a comparison with the ResFinder database. The temperature regime, the composition of the reaction mixtures, and the reaction parameters were optimized; the specificity, sensitivity and reproducibility of the constructed prototype test system were measured.Results and discussion. The spectrum of antibiotic resistance and the profile of resistance genes were determined for the studied strains. To develop multiplex PCR, we selected the most common in the V. cholerae populations genes, which are responsible for resistance to tetracycline (tetA), streptomycin (strA), florfenicol/ chloramphenicol (floR) and trimethoprim/sulfamethoxazole (two variants of the dihydrofolate reductase gene: dfrA1 and dhfR), as well as SXT element integrase gene (int). In the reaction, markers were specifically detected in accordance with the genomic resistance profile, which correlates with the phenotypic manifestation of resistance determined by the disco-diffusion method. The sensitivity of the developed panel of primers and probes for V. cholerae strains was 103 –104 CFU/ml. Therefore, taking into account the specificity, rapidity and simplicity of the reaction, the developed system of primers and probes can be successfully applied for a preliminary assessment of the resistance of the V. cholerae strains to antimicrobial agents.

The residual antibiotics in different environmental media pose a serious threat to human health and the ecosystem. The high-efficient elimination of antibiotics is one of the foremost works. In this study, chloramphenicol (CAP) was eliminated efficiently by electrocatalytic advanced oxidation process with carbon nanotubes/agarose/indium tin oxide (CNTs/AG/ITO) electrode. The influences of different experimental parameters on the degradation efficiency were systematically studied. Under the optimal conditions (4 V potential, 10 wt% CNTs dosage, and pH = 10), the maximum degradation efficiency of CAP (20 mg L− 1) achieved 88% within 180 min. Besides, the electrocatalytic degradation pathway and mechanism for CAP were also investigated, •O2− played a major role in the process of electrocatalytic degradation. Based on the QSAR (quantitative structure-activity relationship) model, the toxicities of CAP and identified intermediates were analyzed. Compared with the parent compound, the maximal chronic toxicity of intermediate ((E)-3-(4-nitrophenyl)prop-1-ene-1,3-diol) for daphnid increased 197-fold. Besides, the hybrid toxicity of the degradation system was further confirmed via disk agar biocidal tests with Escherichia coli ATCC25922, which changed slightly during the degradation process. Based on the above results, it is worth noting that the degradation pathway and toxicity assessment should be paid more attention to the treatment of antibiotic wastewater.

Background. Antimicrobials used for the treatment and prevention of bacterial infections are mainly released nonmetabolized into the aquatic environment via wastewater. Sometimes, unused therapeutic drugs are released down the drains that could act as selective pressure for the development of resistance. The aim of this study was to assess the bacteriological profile of wastewater in health facilities and determine antibiotic susceptibility patterns of bacterial isolates. Methods. A cross-sectional study was conducted from October 1 to December 26, 2020, in health facility wastewater. A total of 128 samples were collected from health facilities for bacteriological analysis and antimicrobial susceptibility testing. Result. A total of 128 samples were processed, and 81 bacterial isolates were recovered. The most common bacterial isolates were S. aureus (16/81 (19.8%)) followed by Klebsiella spp. (15/81 (18.5%)), E. coli (13/81 (16%)), P. aeruginosa (10/81 (12.3%)), Enterobacter spp. (8/81 (9.9%)), Citrobacter spp. (7/81 (8.6%)), coagulase-negative Staphylococcus (5/81 (6.2%)), Salmonella spp. (5/81 (6.2%)), and Shigella spp. (2/81 (2.5%)). A majority of isolates were resistant to ampicillin (62/81 (76.5%)). Only few isolates were resistant to ciprofloxacin (11/81 (13.6%)), chloramphenicol (13/81 (16%)), and kanamycin (8/54 (14.8%)). A majority of bacterial isolates (57/81 (70.4%)) were multidrug resistant (MDR). Conclusion. Wastewater from the health facilities contains antibiotic-resistant including multidrug-resistant bacteria. Therefore, health facility wastewater should be treated by appropriate wastewater treatment before being released into the environment.

A 38-years-old female with an aortic valve replacement presented to an outside hospital (OSH) with fevers and malaise. Blood cultures revealed VRE which was resistant to linezolid, resistant to ampicillin, non-susceptible to daptomycin (MIC of 8 mcg/mL), and exhibited susceptibility to gentamicin. The patient was therefore initiated on intravenous (IV) daptomycin 6 mg/kg q24h and gentamicin IV 1 mg/kg q8h. However, after 14 days of therapy with daptomycin and gentamicin, the patient was transferred to our institution for the management of cardiogenic shock and hypoxemic respiratory failure. Given the concern for treatment failure, her antimicrobial regimen was changed to IV chloramphenicol 12.5 mg/kg every 6 hours with IV daptomycin 10 mg/kg every 48 hours given an estimated creatinine clearance of 30 mL/minutes. In vitro susceptibilities for chloramphenicol were performed which confirmed susceptibility. A transesophageal echocardiogram revealed a possible abscess at the left coronary cusp and aortic valve dehiscence. The patient underwent aortic valve replacement with aortic root reconstruction. The aortic valve culture grew VRE susceptible to linezolid but resistant to ampicillin and doxycycline. The patient was deemed clinically cured after 42 days of combination therapy with daptomycin and chloramphenicol. After 6 years of follow-up, the patient has not had a recurrent VRE infection. To our knowledge, this is the first case of endocarditis secondary to VRE that was successfully managed with the combination of daptomycin and chloramphenicol.

The purpose of this study is to determine the level of antibiotic residues in poultry meat sold in the city of Almaty, which is a megacity of Kazakhstan, and compare it with the Minimum Residue Level set by World Health Organization and Food and Agriculture Organization. Determination of hormonal growth stimulators (progesterone, testosterone, estradiol-17β) and antibiotics (tetracycline, chloramphenicol, and streptomycin) in poultry was carried out using immunoassay according to the manufacturer’s instruction. The results of monitoring showed that in the Almaty region annually wholesale deliveries of meat products from the USA, Belarus, Ukraine, and Russia are carried out regularly. On average in the region from 2016 to 2019, the specific weight meat imports averaged 47.9% of total consumption. A total of 105 samples were examined by us between 2019 and 2020, including 63-import meat and 42 samples of the meat of local production. Due to the particular importance of this problem, the main focus of the article`s goal is to conduct monitoring studies on imported and domestic meat for the residual content of hormones and antibiotics in poultry meat. As a result of the enzyme-linked immunosorbent assay of poultry meat, an excess level of maximum residue was detected in eight brands of imported meat.

Background Nowadays, dried milk products are highly traded and consumed all over the world, so we aimed in this study to evaluate to what extent whole and skim milk powders are safe and comply with Egyptian standards. Methods Eighty samples of dried milk (50 whole milk powder and 30 skim milk powder) were gathered from several retailers and supermarkets for evaluation of their differing quality and safety parameters. Results The most frequent off-flavors recovered from whole milk powder samples were cooked ones and, in the case of skim milk powder samples, flat ones. Five samples of whole milk powder were of fair quality and three samples of poor quality, according to the sensory evaluation. The compositional parameters, moisture, %, fat, %, protein, %, and acidity, %, were measured as mean values of 3.90 ±0.15, 26.90 ±0.19, 25.53 ±0.27, and 0.99 ±0.03% in the examined whole milk powder samples and 3.77 ±0.08, 1.11 ±0.05, 34.62 ±0.29, and 1.22 ±0.03% in the examined skimmed milk powder samples, respectively. These results were within the range of component requirements set by the Egyptian Standard (2014; ES: 1780/2014) for dried milk products. Also, the microbiological safety of the milk powder samples was analyzed by assessment of the total viable count, total yeast and mold count, Coliforms count, Enterobacteriaceae, E. coli, C. sakazakii, Staphylococcus aureus, Salmonella, and Listeria monocytogenes. Staphylococcus aureus was the most prevalent isolate (36.00% and 6.67%) followed by Enterobacteriaceae (20.00% and 3.33%), of whole and skim milk powder, respectively. Enterobacteriaceae isolates included Enterobacter cloacae ssp. Cloacae, and Pantoea spp., which were specified by traditional biochemical tests and Vitek2 system. All Enterobacteriaceae isolated spp. were resistant to cephalothin, neomycin, tobramycin and colistin sulphate, and sensitive to chloramphenicol, gentamycin and nalidixic acid. E. coli, C. sakazakii, Salmonella, and Listeria monocytogenes couldn't be isolated from all the tested samples. By using Inductive Coupled Plasma - Mass Spectrometer (ICP-MS), we could measure lead and mercury as mean values of 0.243 ±0.069 and 0.261 ±0.052 mg/kg for whole milk powder samples at a percentage of 68.00 and 34.00%, while for the skim milk powder samples they were 0.150 ±0.037, and 0.347 ±0.110 mg/kg at a percentage of 66.67 and 40.00%, respectively. Conclusions Finally, thirty-four whole milk powder and twelve skimmed milk powder samples didn't comply with Egyptian standards, so it is necessary for authorities to put more attention on this and regular monitor it.

Carp (C. carpio) in intensive production causes fish to be susceptible to disease, one of which is caused by A. hydrophila bacteria. Prevention is often done by giving synthetic chemical antibiotics that can be left in fish meat. Another alternative is to offer natural ingredients, one of which is bitter melon. The aim of the study was to determine the effect of bitter melon extract (M.charantia) on differential leukocytes (lymphocytes, monocytes and neutrophils) in carp (C. carpio) infected with A. hydrophila bacteria. This research method used a completely randomized design (CRD) with 4 treatments and 3 replications. The treatments used were the administration of different extract doses, namely: treatment A (550 ppm), treatment B (650 ppm), treatment C (750 ppm), and treatment D (850 ppm). positive (K+) with bacterial infection of 107 cells/ml and administration of antibiotics chloramphenicol 0.03 mg/L and negative control (K-) with bacterial infection of 107 cells/ml. Blood collection when the fish are healthy, after offering the bitter gourd extract and after being infected. The results showed that bitter melon extract had a significantly different effect on leukocyte differential. The highest value obtained from treatment D (850 ppm) with the percentage of lymphocytes (18.67-28)%. neutrophils (2.32 = 6.0)% and monocytes (21-26.67)%. In conclusion, treatment with D dose of 850 ppm used as an immunostimulant can increase the differential leukocytes.

In this study, the aim was to explore the effectiveness of the UV/H2O2 photolysis (UVP) process in terms of antimicrobial activity reduction and increasing the mean oxidation number of carbon (MONC) under the degradation of chloramphenicol (CHPL) drug. CHPL degradation kinetics and the effects of foreign anions on CHPL degradation were explored in this study. The order of the inhibition effect was found as Cl− > NO3− > HCO3− due to their different in HO• radical scavenging capacity. A pseudo-first-order model for CHPL degradation was well established, and the rate constant (kobs) was 2.93 × 10−2 min−1 (R2 = 0.98) in UVP. Thirteen intermediate products were detected in MS-chromatogram and were identified through different proposed degradation pathways. The cleavage of the amide side chain in CHPL was more effective in CHPL degradation due to an electrophilic attacks by HO. radicals on it. The inactivation rates of E. coli were decreased due to the reduction of -NO2 group into -NH2 functional group in CHPL that leads to the production of low toxic compounds on CHPL degradation. HIGHLIGHTS Degradation of chloramphenicol drug occurred by UV-irradiation and hydrogen peroxide together.; HO• radical formed in the presence of H2O2 could effectively contribute to the degradation of CHPL.; MONC was increased with increasing the formation of daughter fragments.; Reduction of CHPL decreases the antimicrobial activity.; Dynamics of drug cleavage follows pseudo-first-order kinetics.

The use of antibiotics is an alternative to reduce disease incidence and is used to increase egg-laying hens. This study aims to detect the presence of antibiotic resistance to resistance coding genes in Pseudomonas aeruginosa bacteria. The cloacal swab samples were collected randomly as many 66 samples from several egg-laying hens farms in Cianjur Regency, West Java. The collected isolates were examined bacteriologically. The results of the antibiotic sensitivity test of 8 samples (12.1%) of the Pseudomonas aeruginosa showed the resistance level of antibiotics class tetracycline (tetracycline50%, oxytetracycline75%, and doxycycline50%), fluoroquinolone (enrofloxacin 12.5%), and phenicol (chloramphenicol 12.5%). Pseudomonas aeruginosa was resistant to tetracyclines, oxytetracyclines, doxycycline, enrofloxacin and is sensitive to chloramphenicol. The detection of resistance coding genes showed the genes amount of tetA (62.5%) and qnrS (75%). Efforts to determine the level of resistance and use of antibiotics in farms need regular surveillance and monitoring to ensure the wise use of antibiotics.

Purpose of the study. To conduct a clinical trial of the local treatment efficacy of skin and soft tissue inflammatory processes combination with sodium carboxymethylcellulose, immobilized miramistin and metronidazole.Patients and methods. The study involved patients with purulent-inflammatory skin processes, divided into two groups – control and experimental – 30 in each. The most common nosological form were abscesses of various localization. In the control group, local treatment was carried out with dioxomethyltetrahydropyrimidine ointment with chloramphenicol, and in the experimental group – with a combination of sodium carboxymethylcellulose with miramistin and metronidazole. We studied the local temperature, wound pH, wound planimetry, the appearance of wounds, the species composition of infectious agents in the discharge from the wound, a general blood test (with the determination of leukocyte indices), blood biochemical parameters, and the number of bed-days in the hospital. The data obtained were processed statistically.Results. The percentage of reduction in the area and volume of wounds in the experimental group was significantly higher than in the control. The maximum rate of wound healing in the experimental group was noted on days 1-3 and amounted to 9.7 (6.3; 15.5) % / day, and in the control group – 5.6 (2.9; 7.7). Starting from the 5th day of treatment, the local temperature indices in the experimental group were significantly lower than in the control group, and the pH values of the wounds in the experimental group tended to neutral values from the 5th day of treatment, and in the control group there was an increase in pH. Most often, S. epidermidis and S. aureus were inoculated from the wound discharge (in total, more than 50 % of observations); in the control group, pathogenic microorganisms were inoculated 1.6 times more often than in the experimental group.Conclusion. Patients in the experimental group were hospitalized for 2.5 days less than patients in the control group. It is possible to recommend further study and application of the combination of miramistin and metronidazole immobilized on the sodium salt of carboxymethylcellulose in the treatment of wounds.

Salmonella typhi adalah bakteri patogen penyebab utama demam tifoid. Upaya yang dilakukan untuk pengobatan infeksi bakteri Salmonella typhi adalah dengan penggunaan antibiotik. Namun terdapat laporan yang menyatakan bahwa bakteri ini telah mengalami resisten terhadap antibiotik kloramfenikol, kotrimoksazol, dan amoksisilin. Selain itu, penggunaan antibiotik dalam jangka waktu lama dapat memberikan efek samping bagi tubuh manusia yaitu menyebabkan terjadinya gangguan fungsi pada hati, ginjal dan jantung. Solusi yang dapat dilakukan guna mengurangi penggunaan antibiotik yaitu dengan menggunakan bahan alam. Tanaman yang memiliki potensi sebagai antibakteri adalah johar (Cassia siamea Lamk). Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri ekstrak etanol daun johar (Cassia siamea Lamk) terhadap Salmonella typhi beserta nilai Konsentrasi Hambat Minimum (KHM) dan Konsentrasi Bunuh Minimum (KBM). Metode uji yaitu difusi dan dilusi. Larutan ekstrak daun johar dibuat seri pengenceran dengan konsentrasi 100%, 75%, 50%, dan 25%. Uji fitokimia pada penelitian ini meliputi uji kandungan senyawa flavonoid, alkaloid, saponin, dan tannin. Hasil uji menunjukkan bahwa keempat senyawa tersebut terkandung dalam ekstrak daun johar. Hasil penelitian menunjukkan bahwa ekstrak etanol daun johar mempunyai aktivitas antibakteri terhadap Salmonella typhi. Konsentrasi ekstrak etanol daun johar (Cassia siamea Lamk) 100% memiliki zona hambat paling besar terhadap pertumbuhan bakteri Salmonella typhi dengan zona hambat sebesar 9,9 mm dan konsentrasi ekstrak etanol daun johar 25% memiliki diameter zona hambat terkecil yaitu 6 mm. Nilai KHM ekstrak daun johar terhadap bakteri Salmonella typhi tidak bisa ditentukan, sedangkan nilai KBM adalah sebesar 12,5%.

Phytochemical investigation of the fruit of Acronychia pedunculata (L.) Miq. led to the isolation of a new prenylated flavone, acroflavone A (1), together with eight known compounds (2-9). Their structures were elucidated by thorough analysis of mass spectrometric and NMR spectroscopic data. The isolated compounds were evaluated against several bacterial strains. Three known compounds (3-5) demonstrated antibacterial activities. Among them, acrovestone (5) proved equally or more potent than chloramphenicol against three out of the four strains tested.

We have developed a simple, robust environment-friendly and efficient method for ZnO nanoparticles biosynthesis using Dalbergia sissoo fresh leaf extract. Before using these nanoparticles for antimicrobial assay, a detailed characterization was performed using techniques like Ultraviolet/Visible (UV/Vis) spectroscopy, Particle size analysis (PSA), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM),Transmission electron microscopy (TEM) etc. The average size of biosynthesized ZnO nanoparticles was around 30 nm and they were pure and crystalline by nature. The effectiveness of these biosynthesized nanoparticles were checked against both pathogenic and non-pathogenic microbes. A total of eight bacterial strains-Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Klebsilla pneumoniae, Staphylococcus aureus, Streptococcus entericus, Bacillus cereus, Pantoea cypripedii and three fungal strains-Candida albicans, Aspergilus niger and Aspergilus flavus were studied to have a clear view of the spectrum of ZnO nanoparticles anti-microbial activity. The effectiveness of biosynthesized ZnO nanoparticles against the microbes was found to be better than the standard reference antibiotics used (streptomycin, chloramphenicol and rifampicin). The results seem to be very promising and can be used for some practical applications of ZnO nanoparticles in nearfuture.

Chunhong Liu,1,2,* Baixing Ding,3,* Jian Ji,1 Zhujian Wang,1 Huiwen Chen,1 Wenjun Cao1,2 1Clinical Laboratory, Eye & ENT Hospital, Fudan University, Shanghai, People’s Republic of China; 2Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, People’s Republic of China; 3Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Wenjun Cao Email wgkjyk@aliyun.comPurpose: To report antibiotic resistance rates and trends of common ocular isolates collected over a 15-year period.Methods: We collected 3533 isolates from July 1, 2005 to July 31, 2020. Antibiotic sensitivity was determined according to the guidelines of the Clinical and Laboratory Standards Institute. Chi-squared (χ2) test was used to analyze changes in antibiotic susceptibility over 15 years.Results: Among the 3533 isolates, the predominant pathogens were the staphylococcal species. Methicillin resistance was observed in 381 Staphylococcus aureus (S. aureus) isolates (46.4%) and 1888 coagulase-negative staphylococci (CoNS) isolates (61.1%), and methicillin-resistant (MR) isolates had a high probability of concurrent resistance to fluoroquinolones and aminoglycosides. The mean percentage of resistance in staphylococcal isolates did not reach statistical significance across patient age groups (P = 0.87). Methicillin resistance did not increase in the CoNS (P = 0.546) isolates, and resistance to methicillin slightly decreased among S. aureus (P = 0.04) isolates over 15 years. Additional exploratory analysis revealed a small decrease in resistance to tobramycin (P = 0.01) and chloramphenicol (P < 0.001) among the CoNS isolates. All staphylococcal isolates were susceptible to vancomycin.Conclusion: Staphylococci were the most common microorganisms responsible for causing ocular infections. Antibiotic resistance was high among staphylococci, with nearly half of these isolates were resistant to methicillin and these had a high probability of concurrent resistance among MR staphylococci to other antibiotics. Overall, ocular resistance did not significantly change during the 15-year study period. We conclude that continued surveillance of antibiotic resistance provides critical data to guide antibiotic selection.Keywords: methicillin, antibiotic resistance, ocular isolate, staphylococci

Titin is a giant elastic protein which is responsible for passive muscle stiffness when muscle sarcomeres are stretched. Chloramphenicol, besides being a broad-spectrum antibiotic, also acts as a muscle relaxant. Therefore, it is important to study the interaction between titin I27 and chloramphenicol. We investigated the interaction of chloramphenicol with octamer of titin I27 using single-molecule force spectroscopy and fluorescence spectroscopy. The fluorescence data indicated that binding of chloramphenicol with I27 results in fluorescence quenching. Furthermore, it is observed that chloramphenicol binds to I27 at a particular concentration ([Formula: see text] 40 μM). Single-molecule force spectroscopy shows that, in the presence of 40 μM chloramphenicol concentration, the I27 monomers become mechanically stable, resulting in an increment of the unfolding force. The stability was further confirmed by chemical denaturation experiments on monomers of I27, which corroborate the evidence for enhanced mechanical stability at 40 μM drug concentration. The free energy of stabilization for I27 (wild type) was found to be 1.95 ± 0.93 kcal/mole and I27 with 40 μM drug was 3.25 ± 0.63 kcal/mole. The results show a direct effect of the broad-spectrum antibiotic chloramphenicol on the passive elasticity of muscle protein titin. The I27 is stabilized both mechanically and chemically by chloramphenicol.

Honey is one of the natural treatments with antibacterial effects such as hydrogen peroxide, low pH and short water activity that may inhibit bacterial growth. This study aimed to determine the activity of honey as antibacterial to bacteria Escherichia coli. Antibacterial activity test was done in vitro through diffusion method by using disk disc in MHA media then measuring the diameter of a clear zone that inhibition zone form growth of Escherichia coli bacteria and scaled it millimetre unit. This research was done in the laboratory of the Faculty of Medicine Universitas Kristen Indonesia. The concentrations used are 10%, 30%, 50%, 70%, 100% by using sterile equates as honey diluents. The control used was chloramphenicol, the results obtained at a concentration of 10% with a zone of 7.6 mm inhibition of honey had been able to inhibit the growth of Escherichia coli bacteria, and the optimum concentration was 100% with a zone of 24.5 mm. This test showed that natural honey could inhibit bacteria, which conclude that honey might be used as alternative medicine in society. Keywords: Antibacterial effect, Escherichia coli, honey

Water pollution is one of the most severe environmental problems that affect public health and can cause diseases as gastrointestinal diseases. Microbial pollution of Lake Manzala was studied in four main localities, Kapoty, Bashtier, Mataryia and Gamil areas which receive a high load of sewage, agricultural and industrial wastes from different sources. A total of 50 bacterial isolates from water and fish were identified using API 20E system, revealed that 20% of these bacterial strains, were related to Escherichia coli (E. coli), which has been subjected to different antibiotics, such as Ampicillin, Penicillin G, Streptomycin, tetracycline, Gentamycin, Chloramphenicol, rifampicin and Cefotaxime. All strains variation of resistance pattern, harboring Plasmid DNA are an indication of risk to human health in the communities around Manzala Lake, from such bacterial pathogens, which live in polluted and stressed environment.

Infectious diseases are a problem for public health and can increase patient morbidity and mortality. Bacteria that cause infectious diseases include Streptococcus pyogenes and Proteus mirabilis. Inappropriate use of antibiotics can cause resistance problems and the effects of undesirable drugs. Jamblang (Syzygium cumini) leaf extract can be used as a natural antibacterial drug. There is a study showing the content of active compounds in the leaves of Jamblang are Flavonoids, tannins, alkaloids, and saponins are components of chemical compounds that are suspected as antibacterial. This study aims to determine the antibacterial activity of Jamblang leaf extract against Streptococcus pyogenes and Proteus mirabilis bacteria. The method used is the Minimum Inhibitory Concentration method using well diffusion. The study used Jamblang leaf extract with various concentrations of 10%, 20%, 30%, and 40%, the test bacteria used were Streptococcus pyogenes and Proteus mirabilis, using positive control of chloramphenicol, and negative control of 10% DMSO. The results showed that Jamblang leaf extract can inhibit the growth of Streptococcus pyogenes and Proteus mirabilis bacteria in all concentrations. In the Kruskall Wallis Non-Parametric statistical test the two bacteria obtained P 0.05.In Streptococcus pyogenes bacteria the value of P = 0.031, and Proteus mirabilis bacteria the value of P = 0.015. These results indicate a real difference in this study.

Background and Aims: Sulfonamide drugs are a very old and noted group of small molecules, and are still one of the most important antimicrobial compounds. In this study, starting from sulfonamide drugs, new original compounds containing frequent and functional rings such as thiazole and pyridine were synthesized and their antimicrobial effects were evaluated. Methods: Eighteen new compounds were synthesized by converting the 4-amino group of the sulfonamides to thiourea, and continued by thiazole ring closure. Characterization of the compounds was carried out by FT-IR, H-1-NMR and C-13-NMR and HRMS. MIC values were obtained in antimicrobial activity studies, which were carried out by Broth Microdilution method. Results: Compounds 3p-r had an effect of 32 mu g/ml against B. spizizenii. In addition, compounds 3d-f and 3p-r each showed effect against different gram-positive bacteria. Compound 3r had an MIC of 128 mu g/mL against gram-negative organisms. The rest of the series did not affect gram-negative bacteria. In the study, chloramphenicol and sulfamethoxazole were used as standards. Conclusion: Sulfanilamide and sulfadiazine derivatives showed higher inhibitory effects compared to the rest of the series. 3d-f and 3p-r showed inhibitor activity against gram-positive bacteria, conversely to the standard drug sulfamethoxazole, which possibly means that the mechanism of action is not same.