Trichoderma species as Biocontrol Agent against Soil Borne Fungal Pathogens

Soil borne pathogenic fungi are of major concern in agriculture which significantly decreases the plant yield. Chemically controlled plant imposes environmental threats potentially dangerous to humans as well as other animals. Thus, application of biological methods in plant disease control is more effective alternative technique. This study was carried out to isolate Trichoderma species from soil sample and to assess its in vitro biocontrol efficacy against fungal pathogens viz. Sclerotium rolfsii, Sclerotionia sclerotiorum, Fusarium solani and Rhizoctonia solani. Biocontrol efficacy testing of isolates against different fungal pathogens was performed by dual culture technique.In this study, 5 different Trichoderma species were isolated from 26 various soil samples and were tested against four fungal soil-borne pathogens. Inhibition percentage of radial growth of Sclerotium rolfsii by three of the Trichoderma isolates was found to be 100%; about 62% and 68% of maximum inhibition was observed against Rhizoctonia solani and Fusarium solani respectively whereas Sclerotionia sclerotiorum was inhibited maximum up to 23%. This in vitro study revealed that although Trichoderma species plays an important role in controlling all type of soil borne fungal plant pathogens, however, isolates as biocontrol agent against Sclerotium rolfsii was found to be more efficient in comparison to other pathogens.Nepal Journal of Biotechnology. Dec. 2017 Vol. 5, No. 1: 39-4

Prevalence of Methicillin-Resistant Staphylococcus aureus in Shrines

Methicillin-resistant Staphylococcus aureus (MRSA) infection in human beings and animals is concerning; it stands out as one of the leading agents causing nosocomial and community infections. Also, marginally increasing drug resistance in MRSA has limited therapeutic options. This study focuses on estimating the prevalence of MRSA in shrines, a place where human and animal interaction is frequent, sharing antibiotic-resistant bacteria, antibiotic-resistant genes, and diseases. A total of 120 environmental swabs were collected from targeted areas during the study period, March 2018 to May 2018. Staphylococcus aureus was identified by growth on mannitol salt agar (MSA), and MRSA by growth on mannitol salt agar containing 4 μg Oxacillin, Gram staining, and conventional biochemical test. Isolates of S. aureus were characterized by antibiotic susceptibility testing using the disc diffusion method. MRSA and methicillin-sensitive S. aureus (MSSA) proportion were 19% and 81%, respectively; a high rate of MRSA was observed in isolates from Thapathali (28.6%). MSSA isolates showed a high rate of resistance to erythromycin (64.7%). MRSA isolates were resistant to gentamicin (50%), cotrimoxazole (25%), erythromycin (50%), and ciprofloxacin (25%). The isolates were susceptible to linezolid (100%), clindamycin (100%), ciprofloxacin (75%), erythromycin (50%), tetracycline (100%), and cotrimoxazole (75%). Intermediate resistance was also found in gentamicin (50%). Of the 11 MSSA isolates that were erythromycin resistant and clindamycin sensitive, 6 (54.5%) showed the inducible clindamycin resistance (ICR) pattern and 2 MRSA isolates that were erythromycin resistant and clindamycin sensitive showed ICR pattern. Fifteen MSSA isolates were β-lactamase positive, whereas only two MRSA isolates showed β-lactamase production. There exists a minimal research work on infectious diseases that are shared between primates and animals. This study suggests the pervasiveness of MRSA/MSSA in the shrines, which may be a primary place for pathogen exchange between humans and primates

BACTERIOLOGICAL STUDY OF EAR DISCHARGE IN BIR HOSPITAL

Discharge from the ear is one of the commonest symptoms of infections of the ear. With a view to study the major strains of bacteria encountered in ear discharges, this study was conducted in Microbiology Laboratory, Bir Hospital. The study was conducted for a period of 6 months from January 2000 - July 2000. A total of 224 samples of aural discharges of the outpatients were collected and analysed for bacterial growth. These samples were cultured with the use of standard microbiological techniques and the antibiotic sensitivity pattern of the isolates was also studied in vitro with the use of disc diffusion method. Among 224 patients, 50.9% were male and 49.1% were female and the age of the patients varied from 6 months to 76 years. Majority of the patients with discharging ear belonged to the age group 11-20 years. Bacterial growth was found in 82.6%. The bacterial isolates were of 13 different species. Staphylococcus aureus was the most frequently isolated organism (49.4%) followed by Pseudomonas aeruginosa(20.9%). Other organisms isolated were Coagulase negative Staphylococci (CONS), Streptococcus spp., Bacillus sps., Escherichia spp., Proteus spp., Enterobacter spp., Klebsiella spp., Acinetobacter spp., Edwardsiella spp.The prevalence of gram positive bacterial isolates was higher than gram negative bacterial isolates. 58.0% of samples showed positive correlation with direct smear gram stain and culture results. Among the antibiotics used, Ciprofloxacin was found to be the most effective (80.2%) for overall bacterial isolates followed by Gentamicin (68.9%). The result of antibiotic sensitivity was almost similar to gram positive as well as gram negative isolates. Key Words: Aural discharge, Gram stain, culture, sensitivity

MICROBIAL QUALITY OF MILK AVAILABLE IN KATHMANDU VALLEY

With an objective to find microbial quality of the market milk available in Kathmandu valley, this study was conducted in the Microbiology Laboratory, Himalayan College of Agriculture Science and Technology (HICAST). Different milk brands were collected from different outlets in the valley and analyzed for microbial quality. The samples were cultured using the standard microbiological techniques. Almost all the samples showed the presence of bacterial growth including coliform bacteria. The bacterial isolates were of 7 different genera. E. coli was the most frequently isolated organism (92%) followed by coagulase negative Staphylococci (CONS) (24%). Other organisms isolated were Bacillus species, Staphylococcus aureus, Streptococcus species, Salmonella species, Shigella species. The culture results were similar to direct microscopic count results and showed that bacterial contamination in some of the samples was too numerous to be counted. Thus, it was concluded that the market milk available in Kathmandu is contaminated with various types of microorganisms and does not meet the required standard. The dairy industries should work seriously to maintain the standards of their products. * Integrated Bioscientific Research Group (BIOINT), Kupondol, Lalitpur, Nepal. ** Himalayan College of Agriculture Science and Technology (HICAST), Gatthaghar, Bhaktapur, Nepal. Address for correspondence : Charu Arjyal Integrated Bioscientific Research Group (BIOINT), Kupondol, Lalitpur, Nepal. Email: [email protected] Key Words: Microbiology, Contamination, Milk, Quality, Coliform

Phenotypic characterization of ESBL-producing urinary isolates of E. coli and Klebsiella spp. in a tertiary care children's hospital in Nepal

Abstract Background The production of extended-spectrum beta-lactamases (ESBLs) among uropathogens, particularly E. coli and Klebsiella spp., poses a severe public health concern. This study explored the epidemiology of ESBL-producing E. coli and Klebsiella spp. isolated from urine samples obtained at a tertiary care children's hospital in Nepal. Methods A cross-sectional study was conducted from August 2016 to February 2017. A total of 745 clean catch urine samples were obtained from pediatric patients under the age of 13 and subjected to semiquantitative culture. E. coli and Klebsiella spp. were identified using standard laboratory protocols. Antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion method, and ESBL producers were phenotypically identified using the combined disk method. Results Among the bacterial isolates, E. coli predominated, accounting for 139 (81.8%) positive cases. Notably, E. coli showed high susceptibility to nitrofurantoin, with 117 (84.2%) isolates being susceptible. Meanwhile, K. pneumoniae showed high susceptibility to gentamicin, with 21 (91.3%) isolates being susceptible. Of the 163 isolates of E. coli and Klebsiella spp., 62 (38.0%) were identified as multidrug-resistant (MDR), with 42 (25.8%) confirmed as phenotypic ESBL producers. Remarkably, all 41 (100%) ESBL-producing E. coli isolates were susceptible to imipenem. Conclusions The prevalence of ESBL producers among E. coli and K. pneumoniae isolates from pediatric patients underscores the importance of antimicrobial stewardship. Nitrofurantoin and gentamicin emerge as effective empirical treatment choices against these pathogens in children. However, the high rates of multidrug resistance and ESBL production highlight the necessity for routine surveillance, and early detection strategies to manage such infections effectively