Evaluation of Antimicrobial Activities of Fractions of Plant Parts of Pterocarpus santalinoides

Aims: The study aims to investigate the antimicrobial activities of the leaves, seeds, bark, and root of Pterocarpus santalinoides plant. Study Design: Agar well diffusion and Agar well dilution methods were used to test the preliminary antimicrobial and minimum inhibitory/bactericidal/fungicidal concentrations respectively of Pterocarpus santalinoides plants. Place and Duration of Study: Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Agulu Campus, Nigeria, between February – October, 2017. Methodology: Primary extraction and fractionation of the plant parts were undertaken with methanol, butanol, ethyl acetate, and n-hexane. Agar diffusion method for the primary antimicrobial screening on Muller-Hinton agar (bacteria) and Sabouraud dextrose agar (fungi) were used to assess the antimicrobial activities of the sixteen (16) samples on some microbial isolates namely Salmonella typhi, Escherichia coli, Candida albicans, Aspergillus niger, Microsporon canis, and Trichophyton rubrum. The minimum Inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration (MBC/MFC) and percentage inhibition diameter growth (PIDG) of the samples that yielded positive activity were also evaluated. Results: Twelve (12) samples exhibited inhibitory activity on at least one or more of the test isolates. The MIC range observed for the extracts and fractions that yielded positive activity was 12.5 – 100 mg/ml. The n-hexane fraction of the plant root indicated the best value of 12.5 mg/ml against M. canis. The best MBC/MFC value of 25 mg/ml was observed with the ethyl acetate fraction of the bark (against E. coli and M. canis) and the n-hexane fraction of the root (against M. canis). The result showed S. typhi to be the most sensitive organism to the metabolites of P. santalinoides. Extended-spectrum activity was observed with the ethyl acetate fraction of the bark against three (3) of the test isolates namely S. typhi, E. coli and M. canis. The determination of PIDG values for the test organisms against the plants’ extracts/fractions showed that crude methanol extract (28.57%) and ethyl-acetate fraction (0.14%) of the leaves, butanol fraction (0.14%) of the root (all against S. typhi) were the most potent test samples. Conclusion: The results indicated that the plant parts may have potential medicinal values and confirmed its use in traditional medicine.

Preliminary Studies on Isolation, Bile Tolerance and Antibiogram of Potential Probiotics (Probionts) from Locally Fermented Food Products at Beach Market, Nsukka Metropolis, Enugu State, Nigeria

Aims: The study aims to isolate, evaluate bile tolerance and antibiogram studies of potential probiotics (Lactobacillus spp) from locally fermented Food Products (Akamu, Aqua Rafa® Yoghurt, Ogiri, Okpeye) and Kunu at Beach Market, Nsukka. Study Design: A ten - fold serial dilution and spread plate method using De Man, Rogosa and Sharpe (MRS) medium was adopted for isolation of potential Probionts. Place and Duration of Study: Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, University of Nigeria Nsukka, between March - September, 2018. Methodology: Only catalase negative and Gram positive isolates characteristic of lactobacilli were used. Bile tolerance test was performed by monitoring the bacterial growth at different Bile salt concentrations (0.2%, 0.3% and 2%). The antibiogram of the isolates was assessed using the Kirby-Bauer disc diffusion method against commercial antibiotic discs of ampicillin, vancomycin, gentamycin, ciprofloxacin, methicillin and erythromycin. Results: All the 18 screened isolates were tolerant to bile salt at 0.2 % and 0.3 % with inhibition of growth at 2 % bile concentration. All isolates were observed to be resistant to methicillin (100 %) but very sensitive to gentamycin (11%) and ciprofloxacin (22%) respectively. The isolates showed intermediate resistance to other antibiotics: vancomycin (33%), erythromycin (33%) and ampicillin (44%). The decreasing pattern of resistance was thus: methicillin > ampicillin > vancomycin and erythromycin > ciprofloxacin > gentamycin. Isolates from Yoghurt (66.67%) and Ogiri (53.33%) provided most of the resistant isolates. Methicillin would provide best antagonist potential as all the isolates exhibited very high level of resistance (100 %). Conclusion: These results suggest that all the eighteen potential Lactobacillus spp strain show potential for probiotic applications and the locally fermented food products are rich sources of probionts.

Formulation and Evaluation of Niosomes of Benzyl Penicillin.

Benzylpencillin niosomes were formulated using thin film hydration technique. The resultant niosomes were evaluated using surface morphology, particle size and its distribution, encapsulation efficiency, In vitro drug release, in vivo bioavailability and In vitro antimicrobial activity parameters. Both short (3 h) and long term (24 h) stability studies were carried out on the formulations. The lipid-surfactant ratio and the presence of cosurfactant were identified as the key variables that affect performance of the formulations. The niosomes particle sizes were between 1.67μm to 2.22 μm. The encapsulation efficiency was found to be highest in batch A with value of 82.42 %. Batches B and C exhibited slow release, oral stability and good bioavailability in vivo. For In vitro and in vivo studies, batch B containing span 80,Tween 65 and cholesterol was particularly stable and released its drug content in a controlled manner. The Cmax for the batches were higher than that of pure drug which has value of 55.04 mg/ml in vivo. The IZD of the batches were high against the test micro organisms and all the batches exhibited antimicrobial activities greater than the unformulated drug against S. typhi, P. vulgaris and Ps. Aereuginosa.

Formulation, in vitro and in vivo Characterisation of Diclofenac Potassium Sustained Release Tablets Based on Solidified Reverse Micellar Solution (SRMS).

Aims: To formulate sustained release diclofenac potassium tablets based on solidified reverse micellar solution (SRMS) and to evaluate the in vitro and in vivo properties of the tablets. Study Design: Formulation, in vitro and in vivo evaluation of sustained release diclofenac potassium. Place and Duration of Study: Department of Pharmaceutical Technology and Industrial Pharmacy, University of Nigeria, Nsukka and Department of Pharmaceutics, University of Nigeria, Nsukka 410001, Nigeria. Methodology: SRMS, consisting of mixtures of phospholipid and triglyceride were prepared in the ratios of 1:1, 2:1 and 1:2 (Phospholipon® 90H: Softisan® 154) respectively. SRMS-based tablets containing 100 mg of diclofenac potassium each were prepared using validated plastic mould. The physicochemical properties of the tablet formulations were studied and compared with the market brands of the drug for sustained release properties. In vitro release was carried out in simulated intestinal fluid (SIF, pH 7.5) using the USP paddle method. Anti-inflammatory, analgesic/anti-nociceptive and ulcerogenic properties of the formulated tablets were studied using adult Wistar rats. Results: The results showed that the physicochemical properties of the tablet formulations were significantly affected by the composition/ratio of the lipid matrix (LM) used (p < 0.05). The hardness of the tablets ranged from 4.55 ± 0.50 to 5.10 ± 0.39 kgf for tablets formulated with LM 1:2 and 1:1 (M3 and M1) respectively. Friability results indicated that all the SRMs tablets exhibited friability values less than 1 %. The erosion time ranged from 35.8 ± 1.10 to 120.3 ± 0.32 min. The release profile of the tablets showed maximum release between 8 – 11 h for all the batches. Diclofenac potassium tablets based on SRMS had good anti-inflammatory and analgesic properties and also inhibited the ulcerogenicity of the NSAID by up to 85 %. Conclusion: Diclofenac potassium tablets based on SRMS could be used for once daily administration.

Antagonistic antimalarial properties of pawpaw leaf aqueous extract in combination with artesunic acid in Plasmodium berghei-infected mice.

Background & objectives: Artemisinins, the main stay in the treatment of malaria are used in combinations with other antimalarials to forestall resistance, as artemisinin-combination therapies (ACTs). However, ACTs are expensive and some of the non-artemisinin components are not well-tolerated by patients. There are several folkloric and scientific proofs of the efficacy of herbal remedies for malaria. Mature leaves of Carica papaya is widely used to treat malaria in several African countries. An ACT involving a medicinal herb extract or its active constituent(s) will provide an indigenous alternative/herbal ACT. Methods: Mature fresh leaves of Carica papaya were grounded and macerated in cold distilled water for 24 h and the extract (PCE) was stored in the refrigerator for seven days. Fresh extracts were made as needed. The antiplasmodial activity of PCE and/or artesunic acid were determined by using the Peter’s 4-day suppressive test in Plasmodium berghei-infected mice. The ED50 and ED90 were calculated from the dose-response relationships. Results: The combination of 50 mg/kg of PCE and 15 mg/kg of artesunic acid produced a significant reduction of parasitemia (81.25%), compared to 50 mg/kg PCE alone (37.7%). The mean survival time of the combinations of PCE and 15 mg/kg of artesunic acid, and PCE alone followed a dose-dependent manner. The ED50 of PCE showed that it has a very good activity. The isobolar equivalent (IE) calculated from the ED90 of PCE in combination with artesunic acid showed that the interaction was antagonistic. Interpretation & conclusion: Although pawpaw alone was found to have a very good activity, its combination with artesunic acid is antagonistic. Combinations of artemisinins and pawpaw show little promise for combination therapy development.