Open Access Short Research Article

Microbial Status and Multidrug Resistance Pattern of Pathogenic Bacteria Isolated from Street Food in Dhaka City, Bangladesh

Avijit Banik, Maruf Abony, Suvamoy Datta, Syeda Tasneem Towhid

Journal of Advances in Microbiology, Page 1-13
DOI: 10.9734/JAMB/2018/44163

Aims: This study aims to evaluate the microbiological safety in street foods available in Dhaka city, Bangladesh.

Study Design: Seven categories of street foods were collected aseptically in triplicates from 10 locations of the most populous areas of Dhaka city, transported to the microbiology laboratory of Center of Excellence, Primeasia University, Dhaka. The samples were analyzed for microbiological quality.

Place and Duration of Study: The study was carried out in Dhaka city, Bangladesh, between November 2015 to March 2017. The microbiological analysis was done at the microbiology laboratory of the Center for Excellence Laboratory (CEL), Department of Microbiology, Primeasia University, Dhaka-1213, Bangladesh.

Methodology: Ninety street food samples belonging to 7 different categories were collected aseptically from ten different places in Dhaka. All samples were tested according to the standard food analysis methods. Total viable count (TVC), total coliform count (TCC), total Salmonella-Shigella count (TSSC) and total S. aureus count (TSAC) were estimated by using Plate Count agar (PCA), MacConkey agar, Salmonella-Shigella agar and Mannitol Salt agar plates respectively. Kirby-Bauer disc diffusion method on Mueller Hinton agar was used to determine the sensitivity of the isolated strains to commonly prescribed antibiotics.

Results: Fried Aubergine, sugarcane juice, potato balls, peanut, rice cake, sweetened coconut, local salty snacks nimki and chanachur, sesame cookies revealed high total viable count (1011 CFU/gm or /mL) and high total coliform count (109 CFU/g or /mL). Some street foods were found to contain potential pathogens such as Escherichia coli, Staphylococcus aureus, Salmonella spp., Vibrio spp. and Campylobacter spp. Some of the isolates of E. coli, S. aureus and Salmonella isolates were found to be resistant against azithromycin (15 µg), sulphomethoxazole (25 μg), penicillin (10 µg), nalidixic acid (30 µg), vancomycin (30 µg) and tetracycline (30 μg).

Conclusion: This study reveals the presence of pathogenic bacteria in street foods of Dhaka, Bangladesh. Hence, there is a necessity for strict surveillance on microbial safety of street foods. There should be public engagement projects for.public awareness against consumption of low-quality and unhygienic street foods of Dhaka, Bangladesh.

Open Access Original Research Article

Production and Optimization of Laccase by Trametes sp. Isolate B7 and Its’ Dye Decolourization Potential

Benjamin Vandelun Ado, Abiodun Anthony Onilude, Tivkaa Amande

Journal of Advances in Microbiology, Page 1-14
DOI: 10.9734/JAMB/2018/44218

Laccases produced by Trametes sp. are extracellular multi-copper oxidases, capable of oxidising large number of xenobiotics including dyes. Challenges often encountered in large-scale utilisation include the high cost of production, low yield and unstable enzymes. Lignocellulosics which abound locally are suitable low-cost alternative substrates for laccase production in Solid State Fermentation. Trametes sp. isolate B7 (GenBank accession number MK024175) was isolated and identified using molecular techniques. The study optimised laccase production using saw-dust of Terminalia superba as well as the application of same for dye decolourisation. Optimal pH and temperature were 5.0 (2356 U/mL) and 25°C (2395 U/mL) respectively. Cu2+, Ca2+, Mn2+ and ammonium chloride induced high laccase production at 1-2 mM (2379 U/mL), 3-4 mM (2385 U/mL), 60 mM (2026 U/mL) and 0.3 g/L (2024 U/mL) respectively. Optimum incubation time, carbon source and inducer were day 18 (2395 U/mL), glucose (2395 U/mL) and 2,2’-azinobis(3-ethylbenzthiazole-6-sulphonate (ABTS) respectively. The purified laccase had a specific activity of 5830 U/mL and a molecular mass of ~36 kDa using N-PAGE. Dye decolourisation potential of the crude enzyme was RBBR 100% (24 hours), Phenol red 28% (48 hours) while Congo red, Malachite green and Crystal violet were 75%, 62% and 40% respectively after 72 hours. The ability of the crude laccase to oxidise Phenol red and other dyes without the use of mediators is an unusual character and makes it a versatile biotechnological tool for many industrial processes including bioremediation of dyes with resultant eco-friendly benefits.

Open Access Original Research Article

Activity of Honey and Propolis on Bacteria Isolated from Diabetic Foot

Hend Shubar, Manal Abdul Gawad, Basma Doro, Najib Sufya, Attiya Alatery, Salah B. Mohamed, Najat Al Magrha

Journal of Advances in Microbiology, Page 1-8
DOI: 10.9734/JAMB/2018/43231

Aims: Diabetic foot ulcer is a significant complication of diabetes mellitus and often proceed lower extremely amputation. Propolis is a naturally occurring anti-inflammatory bee derived protectant resin. Previously, topically applied propolis has been reported to reduce inflammation and improves cutaneous ulcer healing in diabetic rodents. This study aimed to determine the Libyan honey and propolis activity and honey against bacteria isolated from diabetic foot ulcer lesion

Study Design:  In vitro antimicrobial activities of honey and crude hexane and methanolic extract of Libyan propolis against bacteria isolated from diabetic foot ulcer lesion

Place and Duration of Study: Samples collected from patient in Tripoli Iben Nafees Hospital using disc and agar diffusion method.

Methodology: Disk diffusion method on groups of aerobic and anaerobic bacteria were obtained from diabetic foot lesion.

Results: The result showed that the percentage of aerobic bacteria isolated from diabetic lesion was about 74%, which include MRSA, E. coli, Ps. aeruginose, Citrobacter, Pantoea, Proteus, Staphylococcus epidermis, Enterobacter and Serratia bacteria. Whereas anaerobic bacteria reported about 26% of Clostridium, Bacteroides, and Lactobacillus Jensenii.

Conclusion: It was concluded that the honey and propolis extract had antibacterial activity against a different type of aerobic and anaerobic bacteria that were isolated from diabetic foot ulcer lesion.

Open Access Original Research Article

Evaluation of the Antagonistic Activity of Bacteria Isolated from Palm Wine (Raphia vinifera) on Salmonella typhi from Different Sources

O. C. Ojo, S. A. Agboola

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/JAMB/2018/44669

Aim: This study was conducted to evaluate the antagonistic effect of bacteria associated with palm wine from Raphia vinifera on Salmonella typhi, the etiological agent of typhoid fever.

Method: Isolation and identification of bacteria from palm wine and the isolation of S. typhi from different sources were done using standard microbiological techniques. The antagonistic assay of each isolated bacteria on S. typhi was also done using microbiological standard.

Results: The bacteria isolated from the palm wine used comprised six bacteria species namely; Bacillus cereus, Micrococcus roseus, Lactobacillus brevis, Lactobacillus plantarum, Streptococcus lactis and Pseudomonas aeruginosa. Out of the isolated bacteria, Lactobacillus brevis exerted the highest growth inhibitory effect on most of the S. typhi isolated from different sources and also the typed isolate (Salmonella enterica serovar Typhi ATCC 33458) used. The growth inhibition mediated by L. brevis is superior to that of all the conventional antibiotics used.

Conclusion: It is therefore suggested that L. brevis from palm wine (R. vinifera) could be used to treat cases of typhoid fever caused by S. typhi.

Open Access Original Research Article

Phytochemical Screening and Antifungal Activities of Zingiber officinale (Roscoe) on Mycotoxigenic Fungi Associated with the Deterioration of Pennisetum glaucum Grains

Olubunmi A. Ayodele, Felix A. Akinyosoye, Daniel J. Arotupin, Oluwole O. Owoyemi, Ayodele B. Oyindamola

Journal of Advances in Microbiology, Page 1-11
DOI: 10.9734/JAMB/2018/44730

The control of mycotoxigenic fungal isolates associated with deterioration of Pennisetum glaucum grains using Zingiber officinale (Roscoe) roots extracts were investigated in this study. Aqueous, Methanol and acetone solvents were used in the extraction of Z. officinale root extracts. The extracts were screened for phytochemicals which revealed the presence of alkaloids, cardiac glycoside, tannin, saponin, flavonoids and terpenoids. A total of fourteen (14) fungi were isolated from pearl millet grains using standard microbiological method. These include: Aspergillus flavus, Aspergillus niger, Aspergillus oryzae, Aspergillus fumigatus, Penicillum frequentans, Penicillum chrysogenum, Penicillum italicum, Penicillum oxallicum, Fusarium oxysporum, Fusarium subglutinans, Trichoderma harzanium, Beauveria bassiana, Mucor mucedo, Saccharomyces cerevisiae. The antifungal activities of Z. officinale root extracts on fungal isolates from deteriorating pearl millet grains were carried out using agar well diffusion technique. Findings from the study revealed that Z. officianalis extracts demonstrated a varying degree of antifungal activity against the fungal isolates from pearl millet grains. Methanollic extract of Z. officinale displayed the highest antifungal activity against the isolates compared to aqueous and acetone extracts. The result of the commercial antifungal agents revealed the great effectiveness of fluconazole over griseofulvin in the control of mycotoxigenic fungi associated with the deterioration of pearl millet grains. In light of these findings, Z.  officianalis extracts can be employed in the control of mycotoxigenic fungi associated with the deterioration of Pearl millet grains and  can also be developed fully into a biocontrol agent upon purification and used in the control of mycotoxigenic fungi associated with the infection of cereal grains.