31 research outputs found
Technical Note: Development of a Photobioreactor for Microalgae Culture
In view of the technical and biological limitations of open pond systems, a study was conducted to develop a cost-effective experimental photobioreactor that would permit efficient cultivation of microalgae for biodiesel production. The photobioreactor was developed using low cost materi- als, cylindrical translucent tubes and plexiglass. The photobioreactor prototype was equipped with alternative arrangement for light source: solar and fluorescent bulb light. It provides uniform illumination by sunlight and a centrally located fluorescent light powered by electricity and rechargeable dry cells. The 12-chamber photobioreactor each measuring 122cm tall and 36cm in diameter approximately 12 liters; in all, occupies a minimal demand on land area. The 12-chamber photo-bioreactor produced approximately 430gram/day with the application of 2.4 litres of liquid poultry droppings.Keywords:Â photobioreactor, microalgae, culture, translucent tubes, plexiglas
Antibacterial activity of honey and medicinal plant extracts against Gram negative microorganisms
There has been a steady rise in antibiotic resistance of bacteria and this urgently calls for the discovery of alternative therapeutic agents. Honey possesses therapeutic potentials which includes antimicrobial activity. Although the antimicrobial activity of honey has been effectively established against an extensive spectrum of microorganisms, it differs depending on the type of honey. To date, not much extensive studies of the antibacterial properties of South African honeys on enteric microorganisms have been conducted. The objective of this study was to compare the antibacterial activity of extracts of six different honeys with those of medical plants commonly used in South Africa. Using a broth dilution method, the antibacterial activity extracts of six South African honeys and medicinal plants against six enteric microorganisms viz- Enterobacter cloacae, Escheriachia coli, Klebsiella pneumoniae, Citrobacter freundii isolated from geophagia samples and Aeromonas hydrophila and plesiomonas isolated both from stool and water samples using agar well diffusion method was done. Different concentrations of honey and plant extracts were tested against each type of microorganism. Briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against each type of microorganism. Extracts from both South African honeys and medicinal plants showed zones of inhibition that ranged from 6.94 to 37.94 mm. The most susceptible bacteria were Escheriachia coli, Aeromonas hydrophila and Plesiomonas shigelloides. MIC and MBC values of extracts were found in the range of 0.625 to 5.000 mg/ml. Extracts of honey showed good antibacterial activity against most organisms than the standard antibiotics such as Ampicillin and Gentamycin. Honey extracts showed antibacterial activity against most microorganisms which were showing some degree of resistance to commercial antibiotics. Extracts from South African honeys and medicinal plants exhibited variable activities against different microorganisms. This result suggests that the honeys could potentially be used as an alternative therapeutic agent against certain microorganisms.Keywords: Agar well diffusion assay, honey, minimum inhibitory concentration, minimum bactericidal concentrationAfrican Journal of Biotechnology, Vol. 13(4), pp. 616-625, 22 January, 201
Using antenatal care as a platform for malaria surveillance data collection: study protocol
BACKGROUND: While many malaria-endemic countries have health management information systems that can measure and report malaria trends in a timely manner, these routine systems have limitations. Periodic community cross-sectional household surveys are used to estimate malaria prevalence and intervention coverage but lack geographic granularity and are resource intensive. Incorporating malaria testing for all women at their first antenatal care (ANC) visit (i.e., ANC1) could provide a more timely and granular source of data for monitoring trends in malaria burden and intervention coverage. This article describes a protocol designed to assess if ANC-based surveillance could be a pragmatic tool to monitor malaria. METHODS: This is an observational, cross-sectional study conducted in Benin, Burkina Faso, Mozambique, Nigeria, Tanzania, and Zambia. Pregnant women attending ANC1 in selected health facilities will be tested for malaria infection by rapid diagnostic test and administered a brief questionnaire to capture key indicators of malaria control intervention coverage and care-seeking behaviour. In each location, contemporaneous cross-sectional household surveys will be leveraged to assess correlations between estimates obtained using each method, and the use of ANC data as a tool to track trends in malaria burden and intervention coverage will be validated. RESULTS: This study will assess malaria prevalence at ANC1 aggregated at health facility and district levels, and by gravidity relative to current pregnancy (i.e., gravida 1, gravida 2, and gravida 3 +). ANC1 malaria prevalence will be presented as monthly trends. Additionally, correlation between ANC1 and household survey-derived estimates of malaria prevalence, bed net ownership and use, and care-seeking will be assessed. CONCLUSION: ANC1-based surveillance has the potential to provide a cost-effective, localized measure of malaria prevalence that is representative of the general population and useful for tracking monthly changes in parasite prevalence, as well as providing population-representative estimates of intervention coverage and care-seeking behavior. This study will evaluate the representativeness of these measures and collect information on operational feasibility, usefulness for programmatic decision-making, and potential for scale-up of malaria ANC1 surveillance
Evaluation of the antibacterial and anticancer activities of some South African medicinal plants
<p>Abstract</p> <p>Background</p> <p>Several herbs are traditionally used in the treatment of a variety of ailments particularly in the rural areas of South Africa where herbal medicine is mainly the source of health care system. Many of these herbs have not been assessed for safety or toxicity to tissue or organs of the mammalian recipients.</p> <p>Methods</p> <p>This study evaluated the cytotoxicity of some medicinal plants used, inter alia, in the treatment of diarrhoea, and stomach disorders. Six selected medicinal plants were assessed for their antibacterial activities against ampicillin-resistant and kanamycin-resistant strains of <it>Escherichia coli </it>by the broth micro-dilution methods. The cytotoxicities of methanol extracts and fractions of the six selected plants were determined using a modified tetrazolium-based colorimetric assay (3-(4, 5-dimethylthiazol)-2, 5-diphenyl tetrazolium bromide (MTT) assay).</p> <p>Results</p> <p>The average minimum inhibitory concentration (MIC) values of the plants extracts ranged from 0.027 mg/mâ„“ to 2.5 mg/mâ„“ after 24 h of incubation. <it>Eucomis autumnalis </it>and <it>Cyathula uncinulata </it>had the most significant biological activity with the least MIC values. The in vitro cytotoxicity assay on human hepatocarcinoma cell line (Huh-7) revealed that the methanol extract of <it>E. autumnalis </it>had the strongest cytotoxicity with IC<sub>50 </sub>of 7.8 ÎĽg/mâ„“. Ethyl acetate and butanol fractions of <it>C. uncinulata, Hypoxis latifolia, E. autumnalis </it>and <it>Lantana camara </it>had lower cytotoxic effects on the cancer cell lines tested with IC<sub>50 </sub>values ranging from 24.8 to 44.1 ÎĽg/mâ„“; while all the fractions of <it>Aloe arborescens </it>and <it>A. striatula </it>had insignificant or no cytotoxic effects after 72 h of treatment.</p> <p>Conclusions</p> <p>Our results indicate that the methanol fraction of <it>E. autumnalis </it>had a profound cytotoxic effect even though it possessed very significant antibacterial activity. This puts a query on its safety and hence a call for caution in its usage, thus a product being natural is not tantamount to being entirely safe. However, the antibacterial activities and non-cytotoxic effects of <it>A. arborescens </it>and <it>A. striatula </it>validates their continuous usage in ethnomedicine.</p
Much Ado About the TPP’s Effect on Pharmaceuticals
Ocular antigens are sequestered behind the blood-retina barrier and the ocular environment protects ocular tissues from autoimmune attack. The signals required to activate autoreactive T cells and allow them to cause disease in the eye remain in part unclear. In particular, the consequences of peripheral presentation of ocular antigens are not fully understood. We examined peripheral expression and presentation of ocular neo-self-antigen in transgenic mice expressing hen egg lysozyme (HEL) under a retina-specific promoter. High levels of HEL were expressed in the eye compared to low expression throughout the lymphoid system. Adoptively transferred naĂŻve HEL-specific CD4+ T cells proliferated in the eye draining lymph nodes, but did not induce uveitis. By contrast, systemic infection with a murine cytomegalovirus (MCMV) engineered to express HEL induced extensive proliferation of transferred naĂŻve CD4+ T cells, and significant uveoretinitis. In this model, wild-type MCMV, lacking HEL, did not induce overt uveitis, suggesting that disease is mediated by antigen-specific peripherally activated CD4+ T cells that infiltrate the retina. Our results demonstrate that retinal antigen is presented to T cells in the periphery under physiological conditions. However, when the same antigen is presented during viral infection, antigen-specific T cells access the retina and autoimmune uveitis ensues
Quantifying the productivity of selected soils in Nsukka and Abakaliki, Southeastern Nigeria using productivity index
No Abstract
Recommended from our members
THE IMPACT OF FOOD SECURITY AND POVERTY STATUS ON RURAL HOUSEHOLD FARMERS IN IKWO, EBONYI STATE, NIGERIA
Issues relating to food availability, accessibility/affordability, and food utilization remain of utmost importance to various stakeholders including policymakers and academics. As food security becomes a concern, poverty deepens systematically, and the meager income earned could not cover basic needs. The objective of this work was to analyze the food security and poverty status of the household farmers in Ikwo., Ebonyi State, Nigeria. For this study, a multistage sampling technique was used to select seventy-five farming households using a structured questionnaire. Data were analyzed using descriptive and inferential statistics. The study used, Radimer/ Cornell’s questionnaire to measure the food insecurity of households; the Foster-Greer-Thorbecke model was used to measure the poverty status and Logit regression for determinants of food security. The food insecurity measure showed that 74.7% of the households were food secure. This showed that the monthly expenditures of 75% of the households were above the food security index. The poverty measure of the households shows that 21.3% points of the households express the incidence of poverty while 6.63% points and 2.81% points were found to have depth and severity of incidence of poverty, respectively. One out of the nine variables used as predictors of food security was statistically significant at p<0.05 level of probability. The Logit regression model indicated that income significantly influenced food security scenarios with respect to some of the indicators such as gender of household head, age of household head, farm size, farming experience, household size and education. The households’ coping strategies were reduction in meal size by 85.3%, purchasing simple foods (78.7%), and extra income-generating activities (76.0%). The study concluded that most of the households were food secure and 21.3% fell below the poverty line. The Government should provide credible sources to enable farming households increase production and earn more income
THE IMPACT OF FOOD SECURITY AND POVERTY STATUS ON RURAL HOUSEHOLD FARMERS IN IKWO, EBONYI STATE, NIGERIA
Issues relating to food availability, accessibility/affordability, and food utilization remain of utmost importance to various stakeholders including policymakers and academics. As food security becomes a concern, poverty deepens systematically, and the meager income earned could not cover basic needs. The objective of this work was to analyze the food security and poverty status of the household farmers in Ikwo., Ebonyi State, Nigeria. For this study, a multistage sampling technique was used to select seventy-five farming households using a structured questionnaire. Data were analyzed using descriptive and inferential statistics. The study used, Radimer/ Cornell’s questionnaire to measure the food insecurity of households; the Foster-Greer-Thorbecke model was used to measure the poverty status and Logit regression for determinants of food security. The food insecurity measure showed that 74.7% of the households were food secure. This showed that the monthly expenditures of 75% of the households were above the food security index. The poverty measure of the households shows that 21.3% points of the households express the incidence of poverty while 6.63% points and 2.81% points were found to have depth and severity of incidence of poverty, respectively. One out of the nine variables used as predictors of food security was statistically significant at p<0.05 level of probability. The Logit regression model indicated that income significantly influenced food security scenarios with respect to some of the indicators such as gender of household head, age of household head, farm size, farming experience, household size and education. The households’ coping strategies were reduction in meal size by 85.3%, purchasing simple foods (78.7%), and extra income-generating activities (76.0%). The study concluded that most of the households were food secure and 21.3% fell below the poverty line. The Government should provide credible sources to enable farming households increase production and earn more income