Potential of Sambiloto (Andrographis paniculata Nees) Extract against Salmonella Pullorum

Background: Salmonella Pullorum are pathogenic bacteria that causes salmonellosis and causes heavy economic losses in the poultry industry and are zoonotic. Treatment of diseases caused by bacteria generally use antibiotics, but excessive administration of antibiotics causes bacterial resistance and residues in livestock. Major chemical constituents of Sambiloto are andrographolide and flavonoids. Andrographolide has antibacterial effect in addition to being antitoxic, anticancer, anti-inflammatory and antiallergic. Methods: The research was conducted by isolating and identifying Salmonella Pullorum on SSA media and a series of biochemical tests (TSIA, SIM, SCA, urea media and sugar test), manufacturing sambiloto extract, testing the sensitivity of several antibiotics using the disk diffusion method and testing the activation of sambiloto extract against Salmonella Pullorum using the disk diffusion and dilution methods. Result: The result show that sambiloto had antibacterial activity because it contained andrographolide, flavonoids, saponins, alkaloids and tannins and the lowest extract dose that effectively killed Salmonella Pullorum is concentrations of 20%.

Isolation, antimicrobial susceptibility patterns, and risk factors assessment of non-typhoidal Salmonella from apparently healthy and diarrheic dogs

Background Dogs are one of the important asymptomatic carriers of antimicrobial resistant and potentially pathogenic strains of Salmonella. They can harbor large bacterial load in the intestines and mesenteric lymph nodes which can be shed in their feces with the possibility of transmission to humans. Therefore, a cross-sectional study was conducted with the objectives of estimating the prevalence of non-typhoidal Salmonella, assessing the risk factors for dog’s Salmonella carriage, and profiling the antimicrobial resistance pattern of Salmonella isolates among housed dogs in Harar town, Eastern Ethiopia. A total of 415 rectal swab samples were collected from randomly selected dogs. Samples were examined for non-typhoidal Salmonella using standard bacteriologic culture and biochemical tests. The disk diffusion method (Kirby-Bauer test) was employed to evaluate the isolates for their susceptibility against five antimicrobials. Results Non-typhoidal Salmonella were isolated from 26 (6.3%) of the rectal swab samples, with significantly higher occurrence in diarrheic (15.2%) than non-diarrheic (5.5%) dogs. The risk of Salmonella harboring was significantly higher in female dogs than in male dogs (OR = 2.5, p = 0.027). Dogs fecal shedding of Salmonella was relatively higher in households who used offal as a main feed type for their dogs (23.1%; 95% CI = 5–53.8) than those who used leftover food (10.1%; 95% CI = 5.7–16.1) and practiced mixed feeding system (17%; 95% CI = 7.6–30.8). Salmonella isolates showed higher resistance to ampicillin (41.7%), while all isolates were fully susceptible to gentamicin. Moreover, 58.3% of Salmonella isolates showed resistance to at least one of the tested antimicrobials. Majorities (72.7%) of the dog owners had no awareness on the risk of zoonotic salmonellosis from dog and all of the respondents use bare hand to clean dog kennel. Conclusion Our study reveals the importance of both diarrheic and apparently healthy housed dogs in the harboring and shedding of antimicrobial resistant non-typhoidal Salmonella. The risk of non-typhoidal Salmonella spread among pet owners is not negligible, especially in households who use offal as main feed type. Therefore, an integrated approach such as: proper dog handling practices; continuous evaluation of antimicrobial resistance; and rational use of antimicrobials in the field of veterinary sector are necessary to tackle the problem.

Molecular Epidemiology of Salmonella enterica in Poultry in South Africa Using the Farm-to-Fork Approach

The presence of the zoonotic pathogen Salmonella in the food supply chain poses a serious public health threat. This study describes the prevalence, susceptibility profiles, virulence patterns, and clonality of Salmonella from a poultry flock monitored over six weeks, using the farm-to-fork approach. Salmonella was isolated using selective media and confirmed to the genus and species level by real-time polymerase chain reaction (RT-PCR) of the invA and iroB genes, respectively. Antimicrobial susceptibility profiles were determined using Vitek-2 and the Kirby–Bauer disk diffusion method against a panel of 21 antibiotics recommended by the World Health Organisation Advisory Group on Integrated Surveillance of Antimicrobial Resistance (WHO-AGISAR). Selected virulence genes were identified by conventional PCR, and clonality was determined using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). Salmonella was present in 32.1% of the samples: on the farm (30.9%), at the abattoir (0.6%), and during house decontamination (0.6%). A total of 210 isolates contained the invA and iroB genes. Litter, faeces, and carcass rinsate isolates were classified as resistant to cefuroxime (45.2%), cefoxitin (1.9%), chloramphenicol (1.9%), nitrofurantoin (0.4%), pefloxacin (11.4%), and azithromycin (11%). Multidrug resistance (MDR) was observed among 3.8% of the isolates. All wastewater and 72.4% of carcass rinsate isolates were fully susceptible. All isolates harboured the misL, orfL, pipD, stn, spiC, hilA, and sopB virulence genes, while pefA, spvA, spvB, and spvC were absent. In addition, fliC was only present among the wastewater isolates. Various ERIC-PCR patterns were observed throughout the continuum with different subtypes, indicating the unrelated spread of Salmonella. This study concluded that poultry and the poultry environment serve as reservoirs for resistant and pathogenic Salmonella. However, there was no evidence of transmission along the farm-to-fork continuum.

Major Bloodstream Infection-Causing Bacterial Pathogens and Their Antimicrobial Resistance in South Korea, 2017–2019: Phase I Report From Kor-GLASS

To monitor national antimicrobial resistance (AMR), the Korea Global AMR Surveillance System (Kor-GLASS) was established. This study analyzed bloodstream infection (BSI) cases from Kor-GLASS phase I from January 2017 to December 2019. Nine non-duplicated Kor-GLASS target pathogens, including Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Streptococcus pneumoniae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter spp., and Salmonella spp., were isolated from blood specimens from eight sentinel hospitals. Antimicrobial susceptibility testing, AMR genotyping, and strain typing were carried out. Among the 20,041 BSI cases, 15,171 cases were caused by one of the target pathogens, and 12,578 blood isolates were collected for the study. Half (1,059/2,134) of S. aureus isolates were resistant to cefoxitin, and 38.1% (333/873) of E. faecium isolates were resistant to vancomycin. Beta-lactamase-non-producing ampicillin-resistant and penicillin-resistant E. faecalis isolates by disk diffusion method were identified, but the isolates were confirmed as ampicillin-susceptible by broth microdilution method. Among E. coli, an increasing number of isolates carried the blaCTX–M–27 gene, and the ertapenem resistance in 1.4% (30/2,110) of K. pneumoniae isolates was mostly (23/30) conferred by K. pneumoniae carbapenemases. A quarter (108/488) of P. aeruginosa isolates were resistant to meropenem, and 30.5% (33/108) of those carried acquired carbapenemase genes. Over 90% (542/599) of A. baumannii isolates were imipenem-resistant, and all except one harbored the blaOXA–23 gene. Kor-GLASS provided comprehensive AMR surveillance data, and the defined molecular mechanisms of resistance helped us to better understand AMR epidemiology. Comparative analysis with other GLASS-enrolled countries is possible owing to the harmonized system provided by GLASS.

Distribution of serotypes and antibiotic resistance of invasive Pseudomonas aeruginosa in a multi-country collection

Background Pseudomonas aeruginosa is an opportunistic pathogen that causes a wide range of acute and chronic infections and is frequently associated with healthcare-associated infections. Because of its ability to rapidly acquire resistance to antibiotics, P. aeruginosa infections are difficult to treat. Alternative strategies, such as a vaccine, are needed to prevent infections. We collected a total of 413 P. aeruginosa isolates from the blood and cerebrospinal fluid of patients from 10 countries located on 4 continents during 2005–2017 and characterized these isolates to inform vaccine development efforts. We determined the diversity and distribution of O antigen and flagellin types and antibiotic susceptibility of the invasive P. aeruginosa. We used an antibody-based agglutination assay and PCR for O antigen typing and PCR for flagellin typing. We determined antibiotic susceptibility using the Kirby-Bauer disk diffusion method. Results Of the 413 isolates, 314 (95%) were typed by an antibody-based agglutination assay or PCR (n = 99). Among the 20 serotypes of P. aeruginosa, the most common serotypes were O1, O2, O3, O4, O5, O6, O8, O9, O10 and O11; a vaccine that targets these 10 serotypes would confer protection against more than 80% of invasive P. aeruginosa infections. The most common flagellin type among 386 isolates was FlaB (41%). Resistance to aztreonam (56%) was most common, followed by levofloxacin (42%). We also found that 22% of strains were non-susceptible to meropenem and piperacillin-tazobactam. Ninety-nine (27%) of our collected isolates were resistant to multiple antibiotics. Isolates with FlaA2 flagellin were more commonly multidrug resistant (p = 0.04). Conclusions Vaccines targeting common O antigens and two flagellin antigens, FlaB and FlaA2, would offer an excellent strategy to prevent P. aeruginosa invasive infections.

Antimicrobial And Synergistic Activity of The Drug Association of Allium Sativum And Antibiotics Against Group B Streptococcus

Maternal colonization by Group B Streptococcus during pregnancy increases the risk of neonatal infection due to vertical transmission from mother to fetus before or during labor. The aims of this study were to evaluate the antimicrobial activity of SP80 (obtained from RGE) and its synergism associated with the antibiotic against strains of Streptococcus agalactiae. Biomonitoring of SP80 disclosed antimicrobial activity only in fractions F18, F19, F20 and F42. The broth microdilution was used to determine the antimicrobial activity of SP80 and fractions from SP80 and to establish the MIC of SP80 (2.40 mg/mL). By using the disk diffusion method, fifty-five clinical isolates of S. agalactiae and 1 ATCC were tested against the association of SP80 with antibiotic penicillin G and ampicillin, respectively, for synergistic assessment. The association of SP80 with penicillin G showed that the mean of the inhibition halos decreased, but it was not significant, with p<0.07. In contrast, the association of SP80 with ampicillin caused the mean inhibition halos to increase with a p<0.001, a significant result. SP80 has antimicrobial activity against S. agalactiae Gram-positive bacteria, and the association with the antibiotic ampicillin showed a synergistic effect, which did not occur when in association with penicillin G.

The potency of ethanolic extract from corn silk as natural antibiotics for acne-related bacteria: A preliminary study

Introduction: Corn silk or known as herb name stigma maydis is an important medicinal botanical in many traditional medicines worldwide, including jamu, an Indonesia traditional medicine. The exploration of corn silk to treat acne vulgaris is still lacking, therefore the current research was conducted to analyze the activity of ethanolic extract from corn silk (EECS) against 3 acne-related bacteria, Propionibacterium acnes, Staphylococcus epidermidis and Staphylococcus aureus. Materials and Methods: The antibacterial activity of EECS at concentration range of 10 to 100% v/v was evaluated using the disk diffusion method. As comparation, distilled water was used as a solvent control, while 1% clindamycin was used as a positive control. Results: Shinoda’s test showed that flavonoid was detected in the EECS. The higher concentration of EECS exhibited higher diameter of inhibition zone indicating higher antibacterial activity on P. acnes, while the antibacterial activity of S. epidermidis was not increased at similar concentrations of EECS. The antibacterial activity of EECS against S. aureus decreased at the higher EECS concentration (>70%). Conclusion: Taken together, EECS is a potential as a bioactive source to inhibit the growth of acne-related bacteria P. acne, S. epidermidis and S. aureus. Further investigation is needed to explore the corn silk or stigma maydis as a medicinal botanical in jamu targeted to treat acne vulgaris. Bangladesh Journal of Medical Science Vol. 21(1) 2022 Page : 84-89

Antimicrobial Resistance of Acetobacter and Komagataeibacter Species Originating from Vinegars

Consumers’ preference towards healthy and novel foods dictates the production of organic unfiltered bottled vinegar that still contains acetic acid bacteria. After ingesting vinegar, the bacteria come into close contact with the human microbiota, creating the possibility of horizontal gene transfer, including genetic determinants for antibiotic resistance. Due to the global spread of antimicrobial resistance (AMR), we analyzed the AMR of Acetobacter and Komagataeibacter species originating mainly from vinegars. Six antibiotics from different structural groups and mechanisms of action were selected for testing. The AMR was assessed with the disk diffusion method using various growth media. Although the number of resistant strains differed among the growth media, 97.4%, 74.4%, 56.4%, and 33.3% of strains were resistant to trimethoprim, erythromycin, ciprofloxacin, and chloramphenicol, respectively, on all three media. Moreover, 17.9% and 53.8% of all strains were resistant to four and three antibiotics of different antimicrobial classes, respectively. We then looked for antimicrobial resistance genes in the genome sequences of the reference strains. The most common genetic determinant potentially involved in AMR encodes an efflux pump. Since these genes pass through the gastrointestinal tract and may be transferred to human microbiota, further experiments are needed to analyze the probability of this scenario in more detail.

Pathogens isolated from bovine clinical mastitis and their antimicrobial resistance

This study aimed to isolate aerobic and microaerophilic bacteria from mastitis milk samples, as well as to determine their antibiotic resistance. A total of 196 bovine mastitis milk samples were tested by standard bacteriological methods and with API identification test kits. Antimicrobial susceptibility testing was performed by the Kirby-Bauer disk diffusion method. The results revealed that the predominant isolate was S. aureus, with an isolation rate of 28%, followed by Streptococcus spp. (27%) and E. coli (19%). Isolation rates for Corynebacterium spp., Mycoplasma spp., and Pseudomonas aeruginosa were 11%, 6%, and 4%, respectively. Compared to the bacteria mentioned above, lower percentages were observed for Trueperella pyogenes (2%), Pasteurella multocida (2%), and Klebsiella pneumoniae (1%). A broad evaluation of antimicrobial resistance showed that the pathogens were resistant to tetracycline (68.63%), oxytetracycline (41.57%), ampicillin (39.08%), ceftiofur (38.1%), cephalexin (32.26%), penicillin (31.25%), amoxicillin/clavulanic acid (24.53%), enrofloxacin (24.44%), gentamycin (23.68%), and trimethoprim/sulfamethoxazole (22.09%). This study demonstrated that the sources of bacteria isolated from mastitis bovine milk samples were both contagious and environmental. More importantly, the present results demonstrate a critically high antimicrobial resistance in dairy cattle. For instance, E. coli isolates showed a crucial resistance to commonly used and recommended antimicrobials, including ceftiofur (100%), cephalexin (83.33%), and tetracycline (94.44%). The results of this study may provide valuable information about clinical aspects of bovine mastitis infections and current antimicrobial resistance levels in dairy cattle.

Prevalence of Multidrug-resistant and Carbapenemase-producing Klebsiella Pneumoniae and Pseudomonas Aeruginosa Isolates in Tertiary Care Hospital in Kathmandu, Nepal

Carbapenemases are the enzymes that catalyze β–lactam groups of antibiotics. The carbapenemase producers are resistant to β–lactam antibiotics and are usually multidrug-resistant bacteria challenging widely used therapeutics and treatment options. Therefore, the detection of carbapenemase activity among clinical isolates is of great therapeutic importance. We aimed to study the MDR and carbapenemase-producing Klebsiella pneumoniae and Pseudomonas aeruginosa isolated from various clinical samples at a tertiary care hospital in Nepal. A total of 3,579 clinical samples were collected from the patients visiting the Department of Microbiology, B&B Hospital, Gwarko, Lalitpur. The samples were processed to isolate K. pneumoniae and P. aeruginosa and then subjected to antibiotic susceptibility testing (AST) by the Kirby-Bauer disk diffusion method. Phenotypic detection of carbapenemase activity was performed in the imipenem-resistant isolates by the modified Hodge test (MHT). Of the total samples, 1,067 (29.8%) samples showed significant growth positivity, out of which 190 (17.3%) isolates were K. pneumoniae and 121 (11.3%) were P. aeruginosa. Multidrug resistance was seen in 70.5% of the K. pneumoniae isolates and 65.3% of the P. aeruginosa isolates. Carbapenemase production was confirmed in 11.9%, and 12.2% of the imipenem-resistant K. pneumoniae and P. aeruginosa isolates, respectively, by the MHT. This study determined the higher prevalence of MDR among K. pneumoniae and P. aeruginosa; however, carbapenemase production was relatively low.