Scholarly works in Pharmaceutical Microbiology
Permanent URI for this collectionhttps://repository.ibadanedu.com/handle/123456789/394
Browse
157 results
Search Results
Item Evaluation of some commercial antimicrobial ointments on selected bacterial and fungal strains of clinical importance(College of Medicine, University of Ibadan, 2020) Idowu, P. A.; Oguntifa, P. O.; Olaniran, O. B.Background: Resistance of Klebsiella species to conventional antibiotics is often implicated in increasing nosocomial infections, and is due in part to enzymatic hydrolysis either constitutively and/or inductively. Resistance plasmid factors readily spread mostly through Gram-negative bacterial isolates through conjugative plasmids. This study investigated the presence of extended spectrum beta lactamases (ESBL), profiles of plasmids detected, and resistance to conventional antimicrobial agents among clinical isolates of Klebsiella species from three different sources. Method: Seventy Gram-negative bacterial and lactose fermenters from urine, wounds and sputum specimens from three hospitals in the South West region of Nigeria were studied after identificationwith microbial identification system. Antibiogram was determined using modified Kirby-Bauer disc diffusion method. Phenotypic detection of ESBLproduction was carried out using double-disk synergy tests (DDST). Plasmid DNA were extracted by alkaline lysis method, electrophoresed, viewed by a UV-trans-illuminator, with plasmid size and number determined, following standard protocols Results: Twenty-nine (29) or 41% of the seventy clinical isolates were confirmed as Klebsiella species distributed as: Klebsiella pneumoniae 89.66% (26/ 29); Klebsiella oxytoca 6.89% (2/29) and Klebsiella ozanae 3.45% (1/29). Among the K. pneumoniae isolates, 13 (50%) were from urine, 8 (30.77%) from wounds and 5 (19%) from sputum. Multidrugresistance was observed with the isolates; as 28 (96.5%) were resistance to at least four (4) different classes of antibiotics. Among the 29 isolates, 14 (48.3%) Klebsiella species were ESBL-producers while 15 (51.7%) were non-ESBL producers. The ESBL-producers showed higher antibiotic resistance compared to non-ESBL producers, particularly with respect to β-lactam antibiotics. Plasmid DNA, with sizes range of O.78 - 23 kbp were detected in 17 (58.62%) of the isolates.Conclusion: Multidrug resistance (MDR) phenomenon was observed with Klebsiella species particularly among the ESBL-producers harbouring high-molecular weight plasmids. There is need for routine ESBL-production surveillance and the rational choice of antibiotics for infection management, reduction and containment of spread of antibiotic resistance in clinical settings.Item Antibacterial activity of crude extracts of the leaves of Nauclea latifolia Smith (Rubiaceae) and some selected conventional antibiotics on clinical isolates of Salmonella typhi(The medical and dental consultant association of Nigeria, OOUTH, 2020) Okunye, O. L.; Idowu P. A; Kolade, T. T.Background: Nauclea latifolia Smith (Rubiaceae) is a valuable medicinal plant used in folkloric medicine in the treatment of Typhoid fever. The public health significance of Salmonella typhi, the aetiologic agent in typhoid fever lies in the increasing resistance to antimicrobial agents. Objectives: To determine the antimicrobial potentials of the crude extracts of the leaves of Nauclea latifolia on clinical isolates of Salmonella typhi compared with some conventional antibiotics. Methods: Antibiogram was carried out on 25 biochemically confirmed clinical isolates of Salmonella typhi using disc diffusion method of Kirby Bauer. Nauclea latifolia leaves extracted with ethyl acetate and methanol in a Soxhlet apparatus were screened for secondary metabolites. The minimum inhibitory concentrations (MICs) of the extracts were determined by agar dilution method on the isolates Results: The antibiogram of Samonella typhi showed the following resistance patterns: Augmentin® (24.0%), amoxicillin (44.0%), chloramphenicol (32.0%), gentamicin (20.0%), cloxacillin (96.0%), ciprofloxacin (8.0%), erythromycin (60.0%), tetracycline (32.0%) and cotrimoxazole (60.0%). The extracts showed good antibacterial activity on the clinical isolates including those resistant to antibiotics. The MIC of methanol extract ranged from 1.56mg/ml to 6.25mg/ml and 3.13mg/ml to 25.0 mg/ml for ethyl acetate extract with the exceptionof isolates 11, 12, 19 and 20 with high MIC values as 50mg/ml. The methanol and ethyl acetate extracts gave a yield of 11.7% and 3.5% respectively. Bioactive secondary metabolites were detected from the extracts. Conclusion: The crude extracts of the leaves of Nauclea latifolia contained antimicrobial agents that were active on Salmonella typhi which could be used alone and in supportive with conventional antibiotics for therapeutic management of typhoid feverItem Antibacterial activity against clinical isolates of salmonella enterica serovar paratyphi and brine shrimp lethality assay of trichilia megalantha harms and trichilia welwitschii C. DC(Ethiopian Pharmaceutical Journal, 2020) Idowu, P. A.; Adegbenle, T. A.Increasing resistance of typhoidal Salmonella enterica to conventional antibiotics has caused more cases of typhoid, therapeutic failure, morbidity and mortality; creating the need to search for new and effective antimicrobial agents from medicinal plants. The present study aimed to detect antisalmonella activity and cytotoxicity (safety) status of the stem bark and leaves of two Nigerian medicinal plants, Trichilia megalantha and Trichilia welwitschii. Nine clinical isolates of Salmonella paratyphi, whose antibiogram were determined by Kirby-Bauer disc diffusion method were used. Antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts on the clinical isolates were done by agar cup diffusion and agar dilution methods, respectively. Acute toxicity of the extracts was determined using brine shrimp lethality assay (BSLA). All the nine isolates of Salmonella paratyphi were resistant to ß-lactam antibiotics (augmentin, cefuroxime, ceftazidime and ampicillin) but susceptible to fluoroquinolones (ciprofloxacin, ofloxacin), nitrofurantoin and gentamicin. The crude extracts of the two plants elicited activity against the nine clinical isolates with the bark extracts being more active than the leaf extracts. I. welwitschi was slightly less active than T. megalantha. The MIC and MBC ranged 1.25 -5.0 mg/ ml and 2.5-10 mg/ml, respectively for the plants. The antisalmonella activity of methanolic extracts of both plants were found to be less than that of ciprofloxacin and ofloxacin. With modal cytotoxicity values of 400- 500 ug/ml, the plant parts were considered nontoxic. Therefore, T. megalantha and T. welwitschii could provide a potential source of antibacterial agent(s) for the treatment of Salmonella paratyphoid infections.Item Antibacterial activity against clinical isolates of salmonella enterica serovar paratyphi and brine shrimp lethality assay of trichilia megalantha harms and trichilia welwitschii C. DC(Ethiopian Pharmaceutical Journal, 2020) Idowu, P. A.; Adegbenle, T. A.Increasing resistance of typhoidal Salmonella enterica to conventional antibiotics has caused more cases of typhoid, therapeutic failure, morbidity and mortality; creating the need to search for new and effective antimicrobial agents from medicinal plants. The present study aimed to detect antisalmonella activity and cytotoxicity (safety) status of the stem bark and leaves of two Nigerian medicinal plants, Trichilia megalantha and Trichilia welwitschii. Nine clinical isolates of Salmonella paratyphi, whose antibiogram were determined by Kirby-Bauer disc diffusion method were used. Antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts on the clinical isolates were done by agar cup diffusion and agar dilution methods, respectively. Acute toxicity of the extracts was determined using brine shrimp lethality assay (BSLA). All the nine isolates of Salmonella paratyphi were resistant to ß-lactam antibiotics (augmentin, cefuroxime, ceftazidime and ampicillin) but susceptible to fluoroquinolones (ciprofloxacin, ofloxacin), nitrofurantoin and gentamicin. The crude extracts of the two plants elicited activity against the nine clinical isolates with the bark extracts being more active than the leaf extracts. I. welwitschi was slightly less active than T. megalantha. The MIC and MBC ranged 1.25 -5.0 mg/ ml and 2.5-10 mg/ml, respectively for the plants. The antisalmonella activity of methanolic extracts of both plants were found to be less than that of ciprofloxacin and ofloxacin. With modal cytotoxicity values of 400- 500 ug/ml, the plant parts were considered nontoxic. Therefore, T. megalantha and T. welwitschii could provide a potential source of antibacterial agent(s) for the treatment of Salmonella paratyphoid infections.Item Antibacterial activity against clinical isolates of salmonella enterica serovar paratyphi and brine shrimp lethality assay of trichilia megalantha harms and trichilia welwitschii C. DC(Ethiopian Pharmaceutical Journal, 2020) Idowu, P. A.; Adegbenle, T. A.Increasing resistance of typhoidal Salmonella enterica to conventional antibiotics has caused more cases of typhoid, therapeutic failure, morbidity and mortality; creating the need to search for new and effective antimicrobial agents from medicinal plants. The present study aimed to detect antisalmonella activity and cytotoxicity (safety) status of the stem bark and leaves of two Nigerian medicinal plants, Trichilia megalantha and Trichilia welwitschii. Nine clinical isolates of Salmonella paratyphi, whose antibiogram were determined by Kirby-Bauer disc diffusion method were used. Antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts on the clinical isolates were done by agar cup diffusion and agar dilution methods, respectively. Acute toxicity of the extracts was determined using brine shrimp lethality assay (BSLA). All the nine isolates of Salmonella paratyphi were resistant to ß-lactam antibiotics (augmentin, cefuroxime, ceftazidime and ampicillin) but susceptible to fluoroquinolones (ciprofloxacin, ofloxacin), nitrofurantoin and gentamicin. The crude extracts of the two plants elicited activity against the nine clinical isolates with the bark extracts being more active than the leaf extracts. I. welwitschi was slightly less active than T. megalantha. The MIC and MBC ranged 1.25 -5.0 mg/ ml and 2.5-10 mg/ml, respectively for the plants. The antisalmonella activity of methanolic extracts of both plants were found to be less than that of ciprofloxacin and ofloxacin. With modal cytotoxicity values of 400- 500 ug/ml, the plant parts were considered nontoxic. Therefore, T. megalantha and T. welwitschii could provide a potential source of antibacterial agent(s) for the treatment of Salmonella paratyphoid infections.Item Antioxidant and antibacterial activities of terminalia mantaly H. Perrier (Combretaceae) on multidrug resistant (MDR) wound pathogens(Faculty of Pharmaceutical Sciences, University of Ilorin, 2020) Idowu, P. A.; Oyekan, O. O.; Akinbami, A. N.Multidrug resistant (MDR) wound pathogens have rendered many antimicrobials ineffective in the treatment of infected wounds. Medicinal plants used to treat wound infections, especially in developing countries can furnish new and effective agents. Therefore, Terminalia mantaly used locally to treat infections was evaluated for antioxidant and antibacterial activities. Methanol extracts of leaves and roots were tested at 20 and 10mg/ml on thirty-two clinical isolates of wound bacteria (Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus) from three Nigerian hospitals. Antibacterial activity and Minimum Inhibitory Concentration (MIC) were determined by agar well diffusion and agar dilution methods respectively. Antioxidant activities were evaluated by catalase, lipid peroxidation, hydrogen peroxide and DPPH free radical scavenging activities. The extracts showed good antibacterial activity with zones of inhibition between 12-35mm on all the tested pathogens with better activity on Gram–negative bacteria including the MDR strains. The MICs (and MBC) of leaf and root extracts were between 0.625-5mg/ml (1.25-10mg/ml) and 0.625-5mg/ml (1.25-5mg/ml) respectively. Leaf extract gave good antioxidant activity, better than root (comparable with ascorbic acid) of 73.77% inhibition on hydrogen peroxide scavenging, 76.36% inhibition on lipid peroxidation and 61.68% DPPH radical scavenging activities. Extracts of Terminalia mantaly showed good antioxidant and antibacterial activities, justifying the traditional uses of the plants. Further, the activity on MDR pathogens revealed the plant as a potential source of newer antibacterial agents for treating wound infections caused by MDR pathogens.Item Susceptibility Pattern of Candida albicans from vaginal candidiasis to azole antifungal agents and Extracts of Lannea welwitschii (Hiern) Engl. (Anacardiaceae)(Faculty of Pharmaceutical Sciences, University of Ilorin, 2020) Idowu, P. A.; Oyekan, O. O.; Akinbami, A. N.Increase in resistance of Candida species to antifungal drugs including those of azole group commonly employed to treat vaginal candidiasis is a global health challenge, necessitating the need to seek alternative therapeutic approaches from medicinal plants. This study investigated the susceptibility pattern of Candida albicans to selected azole antifungal agents and extracts from a Nigerian medicinal plant, Lannea welwitschii. Thirty-five clinical isolates of C. albicans collected from University College Hospital, Ibadan, were further identified using Sabouraud dextrose agar, CHROM-agar (Candida), catalase, germ tube and lactose fermentation tests. Susceptibility of the isolates to azole antifungal drugs (fluconazole and voriconazole) and methanol extract of L. welwitschii stem bark at 100 and 50mg/ml were determined using agar-well diffusion method. Minimum inhibitory concentrations (MICs) of the extract and Miconazole (control) were determined using agar dilution method. Using CLSI breakpoint standard; for Voriconazole (25μg), 82.85% of the isolate were resistant, 5.71% intermediate and 11.43% susceptible while for Fluconazole(1μg), 88.57% resistant, 5.71% intermediate and 2.85% susceptible. The isolates showed 83-89% susceptibility to the plant’s extract. The MIC of L. welwitschii and Miconazole on seven (7) selected isolates were 3.1-12.5mg/ml and 1.0-1.6μg/ml respectively. The study showed an increase in resistance of Candida species to azole antifungal agents when compared to previous studies. Extract of Lannea welwitschii showed good anti-candida activity comparable to Miconazole, even on isolates that were resistant to Fluconazole and Voriconazole, and as such may be investigated for treating vagina candidiasis.Item Antimicrobial activity of the obromacacao pod husk extract on isolates of trychophyton species from cases of tinea capitisand related keratinized infections(Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, 2020) Okunye, O. L.; Idowu, P. A.; Igbokwe, C. O.; Kasim, L. S.; Ike, W. E.This study evaluated the antimicrobial activity of Theobroma cacao pod husk extract on isolates of Trichopyton species; T. mentagrophytes, T. tonsurans, T. rubrum and Microsporum canis from Tinea capitis and keratinized infection in Ibadan. Fifty (50) clinical isolates of Trychophyton species in varied ratios were collected fromdermatology unit of the University College Hospital Ibadan. The isolates were subcultured on to Saboraud Dextrose Agar medium fortified with 0.05mg of chloramphenicol and 0.2mg of cyclohexidime and then incubated aerobically at 25-300C for 72 hours and were biochemically differentiated with Urea broth. Phytochemical analysis of the extract and minimum inhibitory concentration (MIC’s) were determined. The gender distribution ratios of the primary source of isolates were 70% males to 30% females. The N-hexane, ethyl acetate and methanol extracts of the CPH gave a yield of 1.29, 2.05 and 3.89 percent respectively. The minimum inhibitory concentration (MIC) of methanol ranged from 1.625 -3.125mg/mL, while the MIC‘s range of 12.5-50mg/mL and 0- 12.5mg/mL were recorded for N-hexane and ethyl acetate extracts respectively. Tannins, saponins, flavonoids alkaloids were detected as bioactive compounds from the CPH extract investigated. The presence of bioactive compounds coupled with varied remarkable MIC's values recorded against the isolates in this study, is indicative of an antifungal potential of the cacao pod husk extract investigated.Item Susceptibility pattern of Escherichia coli from urinary tract infections to antibiotics and methanol extracts of Olax subscorpioidea and Sida corymbosa(Faculty of Pharmaceutical sciences, University of Jos, 2020) Idowu, P. A.; Okanlawon, B. M.; Salam, H. O.Antibiotic resistance in urinary tract infections (UTIs), of which Escherichia coli causes about 80% of cases is on increase, causing mortality, morbidity and increased health care costs. Clinical isolates of E. coli (13) from UTIs were tested for susceptibility to standard antibiotics and extracts of Olax subscorpioidea and Sida corymbosa. Methanol extracts of the plants were screened at 20, 40, 80 and 100 mg/ml against the isolates using agar-well diffusion method while antibiogram was determined by Kirby-Bauer disc diffusion method. The minimum inhibitory concentrations (MICs) of the plants` extracts and two antibiotics were determined by agar dilution method. The isolates were mostly susceptible to ofloxacin and 100% resistance to augmentin. Extracts of the plants showed good and dose-dependent activities, even on the multidrug resistant E. coli isolates. The zones of inhibition of the extracts ranged 9-16 mm while the MICs ranged 0.5-10 mg/ml on the isolates. This study has shown that MDR E. coli in UTIs are still prevalent and that the roots of O. subscorpioidea and stem of S. corymbosa extracts have good antibacterial activities against the isolates. The results justified the traditional use of the plants to treat infections generally and the potential utilization in the treatment of UTIs.Item Preliminary phytochemical screening and Antioxidant Property of Leaf and twig Extracts of Turraea Vogelii Hook. f. ex. Benth (Meliaceae)(Faculty of Pharmaceutical Sciences, University of Ilorin, 2019) Olufadi-Ahmed, H. Y.; Idowu, P. A.This study investigated the phytochemical constituents by screening the pulverized plant material and the antioxidant potential of the extract of the leaves and twigs of Turraea vogelii. The crude powdered leaves and twigs of the plant were subjected to preliminary phytochemical screening using standard procedures. The ethyl acetate extract of the leaves and twigs as well as the methanolic extract of the twigs were subjected to antioxidant activity studies using 1, 1- diphenyl-2-picryl hydrazyl (DPPH) assay, catalase activity assay as well as lipid peroxidation activity. The result of phytochemical screening of the crude powdered leaves and twigs of Turraea vogelii revealed the presence of tannins, flavonoids, saponins, reducing sugars and alkaloid in the leaves while the twigs contained tannins, flavonoids, saponins, reducing sugars and steroids. The results of the DPPH Radical Scavenging activity studies revealed that ethyl acetate fraction of Turraea vogelii twigs has an IC50 of 444μg/ml which was closest to the activity of the reference measured at 409μg/ml. The ethyl acetate fraction of the twigs showed the most promising lipid peroxidation inhibition activity with an MDA concentration of 9.595mMol/g FW when compared with the standard. The catalase enzyme concentration responsible for the mop up of hydrogen peroxide per minute was highest in the methanol extract of twigs at 0.038mMolmin-1g-1. The implication of this study suggests that the twigs of Turraea vogelii has note-worthy phytochemical principles and also has a good natural antioxidant source that may be indicated in the treatment and management of diseases associated with oxidative stress.