Open Access Original Research Article

Prevalence and Antimicrobial Resistance Patterns of Extended Spectrum Beta Lactamase Producing Enterohemorrhagic Escherichia coli Strain O157:H7 from Cattle and Humans in Moshi, Northern Tanzania

Reuben S. Mkala, Kaunara A. Azizi

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/MRJI/2017/32081

Aim: We aimed to determine the prevalence and drug resistance patterns of ESBL producing Enterohemorrhagic Escherichia coli strain O157:H7 (EHEC O157:H7) isolated from cattle and humans in Moshi, northern Tanzania.

Methods: A comparative cross sectional study was carried out to enroll 200 cattle recto-fecal specimens and 107 human stool specimens in Moshi, northern Tanzania. A convenient sampling method was used to enroll human patients with diarrhea or abdominal complaints and rectal fecal specimens from cattle upon consenting a patient, guardian or owner of the cattle. Bacterial isolation, identification and antimicrobial susceptibility testing were performed based on the standard operating procedures (SOPs). The EHEC O157:H7 were phenotypically confirmed by using MacConkey agar with sorbitol (SMCA) whereas, the suspected ESBL producing strains of EHEC O157:H7 were further confirmed by using the Minimum inhibitory concentration (M. I. C.) Test Strip.

Results: About 20 (10.0%) out of 200 recto-fecal specimens collected from cattle were positively confirmed ESBL producing EHEC O157:H7, whereas 10 (9.30%) out of 107 human specimens were confirmed ESBL producing EHEC O157:H7 (Χ2=0.961, P= 0.002). Twelve (6.0%) of the cattle specimens were ESBL producing non-EHEC O157:H7 whereas 21 (19.6%) of human specimens confirmed as ESBL producing non-EHEC O157:H7. A high number of non-EHEC O157:H7 isolates was found in male 13 (20.3%) than in females 8(18.6%) (OR= 1.506, 95% CI= 0.534-4.236). Both cattle (n=20) and human (n=10) isolates revealed high (100%) resistance against Trimethoprim/ sulfamethoxazole and Tetracycline.

Conclusion: Our study revealed that ESBL producing E. coli is common among human patients as well as cattle in Moshi, Tanzania. The study is supporting ‘ONE HEALTH’ approach which ensure a sustainable control and reduction of transmission and spread of drug resistant bacteria in humans and cattle.

Open Access Original Research Article

Microfungi Associated with Sun Dried Rastrineobola argentea Sold in Gucha South District in Kenya

Irene S. Nyamwaka, Anthony K. Nyamache, John M. Maingi

Microbiology Research Journal International, Page 1-8
DOI: 10.9734/MRJI/2017/32067

The mycoflora of sun dried Rastrineobola argentea are associated with deterioration of the fish during sun drying, handling and storage in Gucha South district. A total of six markets were studied from which five wholesalers and thirty retailers were sampled randomly and systematically. A sample of 50 g of Rastrineobola argentea was collected from each participant during the period between September and December 2012. Samples were cultured on dichloran 18% glycerol (DG 18) agar to identify the fungi growing on the dried Rastrineobola argentea. The results obtained showed that thirteen different fungal species were isolated. These were; Absidia spp. (4.05%), Aureobasidium spp. (1.36%), Alternaria spp. (1.36%), Cladosporium spp. (2.70%), Aspergillus niger (17.57%), Aspergillus flavus (9.46%), Aspergillus fumigatus (10.81%), Fusarium spp. (2.70%), Trichoderma spp. (2.70%), Rhizopus spp. (29.73%), Yeasts (5.40%), Penicillium spp. (6.76%) and Mucor spp. (5.40%). The data obtained from the study showed that 83.79% of all the isolates were toxin producing. The presence of mycotoxin producing species in the samples shows that the fish sold in Gucha South district could be a threat to the health of the consumers and therefore measures should be taken to improve their quality.

Open Access Original Research Article

Inhibitory Potential of Ocimum gratissimum L on Bacterial Implicated in ‘Ofe Akwu’ Soup Spoilage

O. C. Eruteya, F. S. Ire, C. C. Aneke

Microbiology Research Journal International, Page 1-8
DOI: 10.9734/MRJI/2017/32554

Aims: The study evaluated the proximate composition, the bacteria present in freshly spoilt ‘ofe akwu’ soup and inhibitory potential of crude ethanol, methanol and aqueous leaf extract of Ocimum gratissimum on the resulting bacteria.

Study Design: This was an analytical study in duplicate.

Place and Duration of Study: Department of Microbiology, University of Port Harcourt, Niger Delta University, Amasoma, and South Africa, between July 2015 and December 2016.

Methodology: Isolation was done using Nutrient agar medium. Conventional and molecular methods were employed in the identification of the isolates. Proximate analysis and antibacterial activity of O. gratissimumagainst the bacteria were done using standard methods.

Results: The proximate analysis shows the chemical composition such as moisture (66.40%), ash (1.42%), carbohydrate (2.74%), protein (6.50%), lipid (14.39%) and fibre (8.55%). The resulting bacteria on the basis of conventional and molecular characterization were identified as Bacillus pumilus strain m414, B. subtilisstrain AIMST 2ME1, B. cereus strain CF7 and Sphingobacterium mizutaii strain AUMC b-161. The ethanol extract (50 to 250 mg/mL) inhibited Bacillus pumilus strain m414 and B. cereus strain CF7 with zones ranging from 7 to 13 mm while the methanol extract (50 to 250 mg/mL) inhibited Bacillus pumilus strain m414, B. subtilis strain AIMST 2ME1 and Sphingobacterium mizutaii strain AUMC b-161 with zones ranging from 5 to 13 mm. None of the isolates was susceptible to the aqueous extract.

Conclusion: The study has shown that bacteria inhibition by O. gratissimum crude extract may be of use in the preservation of the soup.

Open Access Original Research Article

Enhancement the Antibacterial Potential of the Biosynthesized Silver Nanoparticles Using Hydrophilic Polymers

Naeima M. H. Yousef, Hanan A. Temerk

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/MRJI/2017/31738

Silver nanoparticles are well recognized for its antibacterial activity, especially against pathogenic bacteria. In the present study, silver nanoparticles (AgNPs) were biologically synthesized by using the aqueous leaves extract of Datura stramonium followed by capping with one of the hydrophilic polymers: Polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP). The biosynthesized nanoparticles were characterized by UV–Visible Spectroscopy, X-ray diffraction (XRD) and Transmission Electron Microscope (TEM). Antibacterial activity against Escherichia coliKlebsiella pneumoniaePseudomonas aeruginosaEnterococcus sp. and Staphylococcus aureus was determined by a microtitre well method and disc diffusion method. The results revealed that the antibacterial activity of silver nanoparticles is dependent on their concentration and were active against Gram negative and Gram positive bacteria. The antibacterial activity of coated AgNPs was increased in comparison with uncoated.

Open Access Original Research Article

Evaluation of Free Radical Scavenging and Antibacterial Activity of Acalypha wilkesiana and Terminalia catappa Methanolic Leaf Extracts

Mutiat Adetayo Omotayo, Seide Modupe Akoro, Mary Oluwatoyin Avungbeto, Happiness Uwakwe

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/MRJI/2017/32761

Aim: This study evaluates the antioxidant and antibacterial activity of Acalypha wilkesiana and Terminalia catappa methanolic leaf extracts.

Place and Duration of Study: The study was carried out in the Biochemistry and Microbiology Laboratory, Department of Science Laboratory Technology, School of Pure and Applied Science, Lagos State Polytechnic, Ikorodu, Lagos- Nigeria for the period of three months between August and October 2015.

Methodology: Lycophene and β-carotene were assessed using the method of Nagata and Yamashita while total phenolic and total flavonoid content were assessed by the Folin-Ciocalteau assay and aluminium chloride colorimetric assay respectively. The antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and antioxidant compounds profiled on TLC. Antimicrobial activity was assessed by the agar well diffusion technique and mode of action was evaluated by studying the leakage of UV260 and UV280 absorbing materials spectrophotometrically.

Results: The Acalypha wilkesiana and Terminalia catappa methanolic leaf extracts evaluated in this study possessed significant amount of antioxidant compounds lycophene, β-carotene, total phenol and flavonoids. The extracts exhibited antioxidant activity by scavenging DPPH radicals in a dose dependent pattern with IC50 of 53.50, 51.21, 41.83 and 25.61 μg/mL for Acalypha wilkesianaTerminalia catappa, vitamin C and Gallic acid respectively. Also, the plants’ extracts exhibited antimicrobial activity against test organisms and disrupted microbial membrane evident in the increase in absorbance values of UV260 and UV280 absorbing materials with time. Compounds like galangin, morin, chyrinsin, 3-hydroxyflavone, 6-hydroxyflavone were identified in the two extracts.

Conclusion: Acalypha wilkesiana and Terminalia catappa methanolic leaf extracts are potential sources of drugs with antioxidant and antimicrobial activity.