Mrityunjoy Acharjee

Prevalence of vancomycin resistant Staphylococcus aureus (VRSA) in methicillin resistant S. aureus (MRSA) strains isolated from burn wound infections

Objectives: The increase in resistance of methicillin resistant Staphylococcus aureus (MRSA) strains to vancomycin has been perceived as a formidable threat in the therapeutic fields. The present study investigated the vancomycin resistance traits of MRSA isolates [vancomycin resistant S. aureus (VRSA)] collected from burn patients. Materials and Methods: Twenty-nine of 40 isolates of Staphylococcus spp. were identified as S. aureus which were further tested against 20 commercially available antibiotics to determine antibiotic susceptibility patterns. Results: Imipenem was the most potential antibiotic resulting in 90% sensitivity, followed by netilmicin, clindamycin, and nitrofurantoin (80% sensitivity). All isolates were found to be resistant to penicillin. Approximately 75% of them were found to be resistant to methicillin, oxacillin, azithromycin, cipro-floxacin, and tetracycline. Approximately 45% isolates exhibited resistance to amikacin, chloramphenicol, gentamycin, and tobramycin. Twenty-one of the 29 strains of S. aureus were MRSA, of which 11 were resistant to vancomycin when employing the disc diffusion method. However, when the broth micro-dilution procedure was used to measure the minimum inhibitory concentration (MIC) of vancomycin, eight isolates were resistant to vancomycin, six with an MIC of 32 μg/mL and two with an MIC of 64 μg/mL. Conclusion: A significant fraction of VRSA was found among MRSA strains in this study, revealing the necessity for new and effective drugs against MRSA.

Microbiological Contamination and Anti-bacterial Traits of Common Oral Herbal Medicinal Products within Dhaka Metropolis

ABSTRACT Aims: Present study endeavored to examine the growth and survival of microorganisms within 6 categories of oral herbal medicines commonly used by the community within Dhaka metropolis. Methodology: Samples were analyzed for the presence of bacteria and fungi up to 14 days. The microbial analysis was conducted by conventional cultural and biochemical methods. The in vitro anti-bacterial activity of the medicines was also detected employing agar well diffusion method. Results: Initially all samples were found to be contaminated with total viable bacteria (10 2 -10 4 cfu/ml); however, the fungal and pathogenic growth was not observed. In course of time, the bacterial and fungal load increased up to 10 6 cfu/ml and 10 3 cfu/ml, respectively in most of the samples up to 14 days. The staphylococcal growth commenced after 48 hours in all samples and vigorously increased in two samples up to 10 5 cfu/ml. Two categories of samples were found to be populated with

Microbiological profiling and the demonstration of in vitro anti-bacterial traits of the major oral herbal medicines used in Dhaka Metropolis

Present study attempted to assess the level of microbiological contamination in oral herbal medicines, frequently used for medications, through conventional cultural and biochemical tests along with the antibiogram of the isolates. Moreover, the anti-bacterial potential of the herbal medicines was also aimed to be checked by the agar well diffusion method and minimum inhibitory concentration (MIC) assay. Out of 10 categories of liquid oral herbal medicine samples (n = 50) studied, all were found to be contaminated with bacteria (103-105 cfu/mL), specifically with Staphylococcus spp. in 8 samples; while 2 samples harbored Klebsiella spp. Fungal presence was observed only in one sample. Study of antibiogram revealed Klebsiella spp. to be strongly resistant against penicillin G and erythromycin, whereas S. aureus possessed 80% sensitivity. The in vitro anti-bacterial activity was observed in 7 samples. Of them, one sample was found to exhibit the activity against almost all the test bacteria and another was found effective against 5 out of 8 test bacteria. Five samples showed the activity within a minor range while 3 samples were devoid of such trait. Samples 2 and 4 were found to stall the bacterial growth below 10 mg/mL of concentration in MIC test. Overall, the prevalence of specific pathogens was not so significant in the samples studied as well as only one drug-resistant isolate was identified. Besides, the anti-bacterial trait of 5 samples indicated that most of herbal medicines might be considered effective for medication.

Validation of γ-irradiation in controlling microorganisms in fish

Purpose – With a previous throughput of sea fish contamination with microorganisms, the present study extended the array of such spoilage over four other fish samples including Pseudapocryptes elongates, Scomberomorus cavalla, Xenentodon cancila and Otolithoides pama, evaluated the reductive impact of irradiation, and further validated the irradiation methodology in controlling the microbial quality of the sea fish samples. The paper aims to discuss these issues. Design/methodology/approach – Twelve samples of each sea fish were collected from super shops in Dhaka city and a portion of each sample was subjected to γ-irradiation at a dose of 3 kilo gray (kGy). Then, both non-irradiated and irradiated samples were tested for the presence of pathogenic bacteria though culture on different specific media followed by biochemical identification. Drug resistance among the pathogens was also investigated. Findings – Most of the non-irradiated samples were observed to harbor huge bacteria and fungi (1.3×102-1.5×10...

Study of microbial proliferation and the in vitro antibacterial traits of commonly available flowers in Dhaka Metropolis

Abstract Objective To examine the prevalence of microorganisms and the antibacterial feature within commonly available flowers including Hibiscus rosa-sinensis, Ixora coccinea, Ipomoea digitata, Allamanda cathartica, Nymphaea nouchali and Vinca rosea , samples were randomly collected from different areas in Dhaka city, Bangladesh. Methods Conventional cultural and biochemical methods were applied to isolate and enumerate the flower accessing microorganisms. Flower extracts were prepared using the solvent extraction methods and the subsequent antibacterial activities were demonstrated. Results The total bacterial load and fungal load was estimated to be around 10 7 -10 8 CFU/g and 10 5 -10 7 CFU/g, respectively. All samples were found to be shaded with Staphylococcus spp. (˜10 7 CFU/g) while the prevalence of actinomycetes was also observed except for Ipomoea digitata . The prevalence of Gram negative pathogenic bacteria was also noted within more than 50% samples. The in vitro antibacterial activity of these flowers, especially of Ixora coccinea, Hibiscus rosa-sinensis, Allamanda cathartica and Nymphaea nouchali in alcoholic extracts (methanol and ethanol) was notable against most of the tested microorganisms. Conclusions The contaminating microbial flora identified within the flower samples studied could be a potential environmental hazard if disseminated. Conversely the revealed antibacterial traits of the flower extracts would be useful alternate remedies of the synthetic drugs for disease medication.