Open Access Original Research Article

Biostability of Synthetic Crankcase Oils

Anwuli U. Osadebe, Ngozi K. Uma, Chukwuemeka E. Ifenwanta, Gideon C. Okpokwasili

Journal of Advances in Microbiology, Page 1-10
DOI: 10.9734/JAMB/2018/39283

The biostability of used and fresh samples of Lenoil GTX 15W/40 synthetic motor oil and Lenoil GLX 20W/50 synthetic motor oil were examined to investigate potential biodeteriogens and the stability of synthetic crankcase oils to degradation by microbial isolates obtained from them. The degrading bacteria were isolated via enrichment culture technique. Flow rates were established by determining drop rates and the growth profiles were established by monitoring the degree of turbidity, pH, optical densities and total viable counts. It was determined that used oils dropped faster than fresh oils at both low and high temperatures. Isolates from both groups of oils belonged to the genera Bacillus, Actinomyces, Edwardsiella, Pseudomonas, Micrococcus and Citrobacter among the bacteria and Aspergillus, Cladosporium, Cephalosporium, Penicillium and Mucor amongst the fungi. The used oil proved to be a better substrate for microorganisms. Fungi had higher counts than their bacterial counterparts. Used samples had higher microbial counts than fresh samples. The mixed culture of Actinomyces, Edwardsiella, and Pseudomonas, as expected, utilized the oil samples more readily than single cultures. For the single cultures, Pseudomonas showed the greatest degrading capacity for the used crankcase oils while Edwardsiella excelled with regards to the fresh oil. Observed pH dropped from 7.2–7.0 to 6.88–6.0 on average across all the samples. Synthetic crankcase oils are susceptible to attack both prior to use and when in use; it is, therefore, advisable to change the oil regularly to preserve the motor engine.

Open Access Original Research Article

Antimicrobial Activity and Safety of Maesa lanceolata for the Treatment and Management of Selected Bacterial Pathogens

Chemweno Timothy, Mwamburi Lizzy, Korir Richard, Mutuku Angela, Bii Christine

Journal of Advances in Microbiology, Page 1-8
DOI: 10.9734/JAMB/2018/39450

Aim: In vitro antibacterial activity and safety of aqueous, dichloromethane and methanolic extracts of Maesa lanceolata against the selected bacteria.

Methods and Results: Efficacy of air-dried leaves roots, stem bark extracts from M. lanceolata and phytochemicals were determined at the Center for Traditional Medicine and Drug Research laboratory, Kenya Medical Research Institute. Antibacterial activity was tested against; Staphylococcus aureus ATCC (American Type Culture Collections) 25923, Escherichia coli ATCC 27853, Shigella dysentriae and Pseudomonas aeruginosa using broth dilution technique. Stem bark methanolic extracts registered higher activity with zone inhibition diameter (ZID) of 21 mm and Minimum Inhibitory Concentration (MIC) value of 3.91 mg mlˉ1 against S. aureus. E. coli showed the least activity of 6.3 mm ZID and 250 mg mlˉ1 MIC. Phytochemicals present included alkaloids, phenols, terpenoids, anthraquinones and tannins. The selected leaves (dichloromethane and methanol) and stem bark (dichloromethane and aqueous) extracts displayed cytotoxicity concentration (CC50) on Vero E6 cell lines from 206 µg mlˉ1 to 684 µg mlˉ1.

Conclusion: Activity of M. lanceolata extracts confirms its use in folklore traditional medicine.

Significance and Impact of the Study: The findings from this study validate the claim that extracts of M. lanceolata   possess antibacterial activity and justifies their use in herbal medicine.

Open Access Original Research Article

Detection of Resistance Integron in Escherichia coli of Porcine Origin Producing Extended-spectrum Beta-lactamase in Abidjan, Côte d'Ivoire

I. K. Kouadio, N. Guessennd, A. Dadié, V. Gbonon, E. Tahou, S. Kpoda, M. Dosso

Journal of Advances in Microbiology, Page 1-7
DOI: 10.9734/JAMB/2018/39343

Aims: Aim of the study was to detect resistance integrons involved in multidrug resistance phenotypes in Escherichia coli strains of porcine origin producing extended-spectrum beta-lactamases (ESBL).

Study Design: Genotypic study.

Place and Duration of Study: National Reference Center for Antibiotics and Molecular Biology Platform of Pasteur Institute of Côte d'Ivoire, between June 2017 at July 2017.

Methodology: Thirty-five (35) Escherichia coli strains of porcine origin producing extended-spectrum beta-lactamases were collected for study. The strains were analyzed using an antibiotic susceptibility test according to the diffusion method in agar medium. The research of class 1, 2 and 3 resistance integrons was performed using the conventional PCR method.

Results: 25 strains (71%) of E. coli producing ESBL harboured class 1 resistance integrons. None of the isolates carried class 2 and 3 resistance integrons. The strains harbouring resistance integrons were more resistant to amoxicillin, ceftriaxone, cefotaxime, tetracycline with a much higher rate of resistance (71%) compared to integron negative isolates (31%). The resistance to kanamycin and cotrimoxazole were 60% in integron positive isolates. Concerning integron negative isolates, the resistance to kanamycin was 11% and cotrimoxazole 20%.  

Conclusion: The integron positive isolates is one of the major causes of resistance gene dissemination. This represents a risk for public health that must challenge the public authorities on the reasoned use of antibiotics in animal production chains.

Open Access Original Research Article

Assessment of Knowledge on Preventive and Control Measures of Pulmonary Tuberculosis among Inmates and Staff of Abakaliki Prisons, Nigeria: An Implication for Policy Implementation

B. N. Azuogu, N. C. Eze

Journal of Advances in Microbiology, Page 1-11
DOI: 10.9734/JAMB/2018/39305

Background: Pulmonary Tuberculosis (PTB) is one of the major diseases of public health importance especially in prisons where case-finding rate has been low. The WHO established five facts of prisons PTB spread include: Prisons receive TB, Prisons concentrate TB, Prisons disseminate TB, Prisons make TB worse, and Prisons export TB. Poor TB case finding results in annual TB transmission risks of 90%. This study assessed knowledge on preventive and control measures of pulmonary tuberculosis among inmates and staff of Nigerian Prisons, Abakaliki.

Methods: A prison-based cross-sectional descriptive study was undertaken among 307 inmates and staff selected using a systematic sampling technique. Informed consent was obtained from the staff and inmates. The respondents were interviewed using a pre-tested interviewer-administered structured questionnaire. Good knowledge of pulmonary tuberculosis was assessed by the proportion of respondents who correctly answered 60% of the knowledge questions, while sputum test was done for respondents with cough of two weeks or more. Data analysis was done using SPSS statistical software version 22. Chi-squared test was used for bivariate analysis with level of significance set at p-value of less than 0.05. Data were treated with strict confidentiality.

Results: The mean age of inmates was 34.96±5.7 years while that of staff was 38.43±3.5 years. Majority of the respondents had secondary education, while about 46% and 51% of inmates and staff respectively had good knowledge of pulmonary tuberculosis. Predictors of good knowledge were educational and employment status of inmates and staff educational attainment only.

Conclusion: Knowledge on preventive and control measures of PTB was poor among respondents. This level of knowledge especially by the inmates needs to be improved upon by intensified public health campaign. High PTB burden and poor control policies within prisons potentiate high attributable risk. Implementation of current national or international cell occupancy recommendations would reduce TB transmission by 50% and 94% respectively especially now that there is an increase in the incidence of MDR-TB.

Open Access Original Research Article

Investigation of Phytoconstituents, Antibacterial Activity and Cytotoxic Effect of Ficus exasperata Leaf Extracts

A. M. Oyetayo, A. R. Jose, S. O. Bada, T. O. Komolafe

Journal of Advances in Microbiology, Page 1-8
DOI: 10.9734/JAMB/2018/39733

Aim: The aim of this study was to subject Ficus exasperata to standard scientific scrutiny by investigating the phytochemical composition as well as the antibacterial activity and cytotoxic effect of its leaf extract.

Methodology: The plant leaf was air-dried under shade and thereafter ground mechanically, macerated in a solvent (ethanol) for 48 hr and dried using rotary evaporator. The presence of phytochemicals was assayed qualitatively; agar well diffusion method was used to assess the antibacterial activity while brine shrimp assay was used to determine the cytotoxic potential of the plant extract.

Results: The qualitative phytochemical screening of Ficus exasperata leaf extract revealed the presence of alkaloid, tannin, flavonoids and cardiac glycoside whereas saponin and steroids were absent. In the antibacterial activity assay, Klebsiella pneumoniae showed the highest susceptibility against the leaf extracts at all the test concentrations recording inhibition zone range of 7.33±0.58 mm to 18.33±0.58 mm. The least zone of inhibition (11.67±0.58 mm) was recorded against Streptococcus pneumonia at the highest concentration used (50 mg/ml). The lowest minimum inhibitory concentration (2.5 mg/ml) of the extract was found against S. aureus, S. pneumoniae, E. faecalis and K. pneumonia while the highest MIC value (25 mg/ml) was recorded against S. typhi and Ps. aeruginosa. The plant’s leaf extract completely killed three of the pathogens within 10 minutes of exposure these were S. aureus, E. faecalis and K. pneumoniae. Higher mortality percentage of brine shrimp was observed with the increase in concentrations of the extracts with an LC50 value of 39.76 ppm was obtained for the extract.

Conclusion: From the foregoing, there is a great amount of evidence suggesting that the ethanol extract of Ficus exasperata leaf contained bio-active substances which confer on it antibacterial activity and cytotoxic effect. Therefore, it may be expediently exploited in the development of new antibiotics especially against susceptible bacteria.