Open Access Original Research Article

Studies of Bioactive Potentials of the Root Extracts of Elaeis guineensis Jacq. against Pathogens Implicated in Wound Infections

Paul Opeyemi Adeniyi, Oluwaseun Oyetunji Olasunkanmi, David Ayinde Akinpelu, Oludare Femi Ajayi, Joseph Omololu-Aso, Felix Oluwasola Olorunmola

Journal of Advances in Microbiology, Page 1-13
DOI: 10.9734/JAMB/2018/40917

This study was carried out at the Department of Microbiology, Obafemi Awolowo University, Ile-Ife, Nigeria, between April and October, 2014. It was designed to investigate the antimicrobial activities of the root extract of Elaeis guineensis Jacq. on some bacteria implicated in wound infection. This was with a view to obtaining the root extract of E. guineensis and testing its in vitro bactericidal effects, the modes of action on various strains of Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae implicated in wound infections as well as to determine the phytochemical components present in the plant extract that are responsible for the bioactivity.

The root of E. guineensis was harvested from Akinlalu area, Ile-Ife, Nigeria in the month of April, 2014. The plant sample was dried in hot air oven at 45ºC and then ground to fine powder. The powered root was cold extracted using methanol and distilled water (3:2 v/v). The methanolic extract obtained was concentrated in vacuo using rotary evaporator and then lyophilised. The methanolic crude extract was screened for phytochemicals and tested for antimicrobial activity against all the bacterial isolates associated with wound infection. The extract was later partitioned using different organic solvents in the increasing order of polarity starting from n-hexane, chloroform, ethyl acetate and butanol. The antimicrobial potentials of the crude extract and that of the partitioned fractions were determined by agar-well diffusion method. The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) of the crude extract and the ethyl acetate fraction were also determined. Finally, the rate of kill, potassium ions and nucleotides leakages were determined using Staphylococcus aureus and Pseudomonas aeruginosa as representatives of Gram-positive and Gram-negative organisms.

The crude extract and the ethyl acetate fraction exhibited varying degrees of antimicrobial activity while other fractions did not show appreciable antimicrobial activities. The MIC of the crude extract ranged between 0.78 and 12.50 mg/mL and that of the ethyl acetate fraction ranged between 0.63 and 5.00 mg/mL. Phytochemical screening of the crude extract showed the presence of tannins, saponins, steroids and flavonoids. The time-kill assay revealed that the percentage of the cells killed increased with increase in the concentrations of the fractions as well as contact time intervals. A 100% kill was achieved by ethyl acetate fraction on Staphylococcus aureus at 3 x MIC within 120 minutes, whereas 100% kill was achieved by the same fraction on Pseudomonas aeruginosa at 3 x MIC within 30 minutes. Varying amounts of potassium ions as well as nucleotides were leaked by the ethyl acetate fraction from selected bacterial isolates leading to their death. The leakages of these materials were monophasic.

This study concluded that the crude extract along with the ethyl acetate fraction obtained from it exhibited appreciable bactericidal activities at minimal contact time and low concentrations. It also established the root extract of E. guineensis as a potential source of broad spectrum antibacterial drugs in the treatment of wound infections.

Open Access Original Research Article

High Rates of Methicillin-Resistant Staphylococcus aureus Colonization of Domesticated Swine of Kabale District – Southwestern Uganda

Baguma Andrew, Atek Atwiine Kagirita, Owalla Tonny, Bazira Joel

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/JAMB/2018/41085

Background: S. aureus is a commensal mammalian pathogen which can establish itself as part of the skin flora. However, can eventually cause infections and invasive diseases in both hospital and community settings. Livestock-associated Methicillin-resistant S. aureus remains a major concern to public health. This study investigated the rates of methicillin resistance S. aureus (MRSA) colonization and respective antibiotic resistance profiles in domestic pigs in Kabale District - South Western Uganda.

Method: This was a cross-sectional study conducted between June 2016 and February 2017 in which nasal swabs from 585 pigs from 147 homesteads were collected and cultured using standard microbial techniques to isolate S. aureus and phenotypically screen for MRSA using Cefoxitin disc. MecA polymerase chain reaction (PCR) was used to confirm MRSA. Antimicrobial susceptibility testing was performed using the Kirby Bauer technique to determine antimicrobial susceptibility pattern among MRSA towards to the commonly used antibiotics in the region.

Result: From the five hundred and eighty-five (585) pigs, 172 (29.4%) were MRSA. There was high antibiotic resistance among MRSA isolates was observed against Sulfamethoxazole – trimethoprim was 170(99%), Erythromycin; 154(89%), Ciprofloxacin 124(72%), Clindamycin; 121(70), Tetracycline; 121(70%), Gentamycin; 84(49%), Rifampicin; 40(23%); Cefipime; 40(23%) and Vancomycin; 03(2%).

Conclusion: The observed high rate of MRSA colonization among domestic pigs is of a significant public health concern in Kabale region. A greater number of MRSA isolates were highly resistant to commonly used antibiotics.

Open Access Original Research Article

Evaluation of Percentage Degradation of Crude Oil in Contaminated Soil by Isolated Consortia

Nna Orji, Chinenye

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/JAMB/2018/37928

The Biodegradation of spilled crude oil in contaminated soil could reach insignificant quantity and harmless compounds formed through the application of effective and viable hydrocarbon degraders. In this study, 15 micro-organisms were isolated, sub-cultured, purified and used for the bio-augmentation process of a crude oil contaminated soil. The isolated consortium used the crude oil as their sole carbon source and in the process lead to the bio-degradation of the oil contaminant. The quantity of residual oil obtained following bio-augmentation with each isolate was determined gravimetrically. The best hydrocarbon degraders identified include: Staphylococcus epidermis, Pseudomonas Spp, Baccilus Spp, Klebsiella Spp., Micrococcu Spp. These findings from this study have environmental implication as it could help in the selection and application of bacterial species that can be used for effective bio-degradation of crude oil in contaminated soil in the Niger Delta region of Nigeria through bio-augmentation process.

Open Access Original Research Article

Diagnostic Value of 16S rRNA Gene by PCR for Rapid Laboratory Diagnosis of Sepsis in Children

Maysaa El Sayed Zaki, Nermeen Abou El Kheir, Mohamed Mofreh, Bassem El Deek

Journal of Advances in Microbiology, Page 1-7
DOI: 10.9734/JAMB/2018/41657

Background: Sepsis in children is a common health problem. Rapid laboratory diagnosis improves its prognosis by adequate therapy.

Aim: The objectives of the present study were to compare the use of blood culture with detection of 16S rRNA by PCR for detection of bacterial pathogens in children with clinically suspected sepsis below the age of 5 years and to correlate the laboratory findings of 16S rRNA by PCR with the risk factors for sepsis in those patients.

Materials and Methods: The study included 100 consecutive children below 5 years who were suspected to have sepsis on clinical basis. Blood samples were obtained from each child for blood culture by Bact/alert system, CRP and16S rRNA gene PCR amplification.

 Results: In the present study all positive blood cultures samples were positive by 16S rRNA PCR. However, there was one negative sample by blood culture that was positive by PCR. The sensitivity, specificity and accuracy of 16S rRNA PCR compared to blood culture were 100%, 95.5% and 99% respectively.

Conclusion: The present study highlights the advantages of 16S rRNA PCR for rapid laboratory diagnosis of sepsis in children compared to blood culture. The association of positive results with risk factors of sepsis may be used as a guide for in rapid diagnosis in high risk patients.

Open Access Original Research Article

Listeria Species Isolated from the Wastewater Samples of a Private and Tertiary Hospital in Ibadan and their Antibiotics Resistance Patterns

Olutayo I. Falodun, Motunrayo Janet, Amusan

Journal of Advances in Microbiology, Page 1-10
DOI: 10.9734/JAMB/2018/40753

Introduction: In hospitals, a significant amount of water is consumed and equally, significant amounts of wastewater is disposed with high levels of contaminants, including disease-causing bacteria such as Listeria spp. have been found in wastewater effluent and surrounding freshwater bodies. Recent studies suggest that Listeria species readily survive conventional wastewater treatment processes even after tertiary treatment. This study was carried out to determine the antibiotic resistance pattern of Listeria spp. isolated from hospital wastewater (treated and untreated) from private and tertiary hospital samples in Ibadan and comment on the public health significance.        

Materials and Methods: Hospital wastewater samples were collected between April and July, 2016. Listeria Selective Agar Base with Listeria Selective Supplement (Oxoid, UK) was used for the isolation of the Listeria species and the isolates were identified using standard conventional methods. Antimicrobial susceptibility testing was done against ampicillin (10 µg), cloxacillin (5 µg), amoxicillin (5 µg), streptomycin (10 µg), ceftriaxone (30 µg), chloramphenicol (30 µg), ciprofloxacin (5 µg), ofloxacin (5 µg), sulfamethoxazole-trimethoprim (25 µg) and tetracycline (30 µg) by the Kirby-Bauer disk diffusion method.

Results: A total of 96 Listeria spp. were isolated comprising L. monocytogenes 23 (24%), L. innocua 13 (13.5%), L. ivanovii 14 (14.6%) and other Listeria spp. 46 (47.9%).  Furthermore, all the 96 (100%) isolates were resistant to ampicillin while all (100%) the L. monocytogenes and L. ivanovii showed resistance to both ceftriaxone and cloxacillin. In addition, all the L. ivanovii exhibited complete resistance to ciprofloxacin. Also, three (3.1%) isolates (L. monocytogenes, L. ivanovii and Listeria spp.) were resistant to a combination of eight antibiotics (sulfamethoxazole-trimethoprim, chloramphenicol, tetracycline, ampicillin, ceftriaxone, cloxacillin, amoxicillin and ciprofloxacin).

Conclusion: The observation from this study showed that the wastewater from both the private and tertiary hospitals could be a source of transmission of multi-drug resistant bacteria to human and animals. More so, the wastewater treatment processes did not reduce the load of the Listeria species.