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JournalISSN: 1996-0808

African Journal of Microbiology Research 

Academic Journals
About: African Journal of Microbiology Research is an academic journal published by Academic Journals. The journal publishes majorly in the area(s): Antimicrobial & Population. It has an ISSN identifier of 1996-0808. It is also open access. Over the lifetime, 4897 publications have been published receiving 49528 citations. The journal is also known as: AJMR.


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Journal ArticleDOI
TL;DR: An attempt has been made to review different in vitro models for estimating antioxidant properties of natural products from medicinal plants, and a large number of plants showing in vitro antioxidant activity are listed but in vivostudies are lacking.
Abstract: Reactive oxygen species (ROS) are a class of highly reactive molecules derived from the metabolism of oxygen. ROS, including superoxide radicals, hydroxyl radical and hydrogen peroxide molecules are often generated as by products of biological reactions or from exogenous factors. There is extensive evidence to involve ROS in the development of degenerative diseases. Evidence suggests that compounds especially from natural sources are capable of providing protection against free radicals. This has attracted a great deal of research interest in natural antioxidants. It is necessary to Screen out medicinal plants for their antioxidant potential. Therefore an attempt has been made to review different in vitro models for estimating antioxidant properties of natural products from medicinal plants. All the models are described along with the different standards that can be used for estimation. In the end, a large number of plants showing in vitro antioxidant activity are listed but in vivostudies are lacking. Key words: Antioxidant assay, in vitro models, antioxidant medicinal plants.

424 citations

Journal ArticleDOI
TL;DR: In this paper, the antimicrobial activity of ZnO nanoparticles against gram-negative and gram-positive bacteria was determined using bacteriological tests such as disc and well diffusion agar methods, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC).
Abstract: The aim of the present study is to determine the antimicrobial activity of ZnO nanoparticles against Gram-negative and Gram-positive bacteria Escherichia coli (E coli) and Staphylococcus aureus (S aureus) were used as test microorganisms The effects of particle size and concentration on the antibacterial activity of ZnO nanoparticles was studied using bacteriological tests such as disc and well diffusion agar methods, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) These tests were performed in nutrient broth and nutrient agar following standard methods In addition, the effect of different concentrations of ZnO nanoparticles on the growth of E coli and S aureus was measured with respect of time The minimum inhibitory concentration was determined using seven different concentrations of ZnO nanoparticles including 16, 8, 4, 2, 1 and 05 mg/ml The MIC value for E coli and S aureus was 1 and 05 mg/ml, respectively The results showed that ZnO nanoparticles have antibacterial inhibition zone of 29 and 19 mm at the concentration of 10 mg/ml against E coli and S aureus, respectively Gram-negative bacteria seemed to be more resistant to ZnO nanoparticles than Gram-positive bacteria It was found that the antibacterial activity of ZnO nanoparticles increased with decreasing particle size and increasing powder concentration The antibacterial effect of ZnO nanoparticles was time dependent and takes effect gradually ZnO bulk powder showed no significant antibacterial activity Key word: ZnO nanoparticle, Escherichia coli, Staphylococcus aureus, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC)

362 citations

Journal ArticleDOI
TL;DR: This review summarized current researches on fungal endophytes as biocontrol agent against plant pathogens and proposed that endophyte inhibit plant pathogen mainly by inducing phytoalexins production and ecological occupation.
Abstract: Fungal endophytes are a group of microorganism associated with plant and have attracted a great interest to botanist, microbiologist and ecologist. Since they have the ability to benefit host plant growth and defense and can produce various potential commercially valued secondary metabolites, an increasing number of reports pay attention to endophytic screening, identification and production. However, little is known about the regulation of plant-fungal endophytes interaction and how fungal endophytes protect plant from pathogens. This review summarized current researches on fungal endophytes as biocontrol agent against plant pathogens and proposed that endophytes inhibit plant pathogen mainly by inducing phytoalexins production and ecological occupation. Key words: Fungal endophyte, pathogens, plant protection.

238 citations

Journal ArticleDOI
Kerstin Hell1, Charity Mutegi
TL;DR: There is need for efficient monitoring and surveillance with cost-effective sampling and analytical methods to reduce risk of aflatoxin contamination in Africa.
Abstract: Aflatoxins are secondary fungal metabolites that contaminate agricultural commodities and can cause sickness or death in humans and animals. Risk of aflatoxin contamination of food and feed in Africa is increased due to environmental, agronomic and socio-economic factors. Environmental conditions especially high humidity and temperature favour fungal proliferation, but also drought conditions increase risk of aflatoxin contamination. Low-input farming practices compound fungal and aflatoxin contamination of crops. The socio-economic and food security status of the majority of inhabitants of sub-Saharan Africa leaves them few options for choosing low-risk and high quality products. Several technologies have been tested in Africa to reduce aflatoxin risk. Field management practices that increase yields can reduce the risk of aflatoxin development. They include use of resistant varieties, crop rotation, well-timed planting, weed control, pest control especially control of insect pests and avoiding drought and nutritional stress through fertilization and irrigation. Measures to stop the infection process by controlling the aflatoxin causing fungi in the field are achieved through use of pesticides and atoxigenic fungi to competitively displace toxigenic fungi, and timely harvest. Post-harvest interventions that reduce aflatoxin include rapid and proper drying, proper transportation and packaging, sorting, cleaning, drying, smoking, post harvest insect control, and the use of botanicals or synthetic pesticides as storage protectants. Another approach is to reduce the frequent consumption of ‘high risk’ foods (especially maize and groundnut) by consuming a more varied diet, and diversifying the diet into less risky staples like sorghum and millet. Chemo-preventive measures that can reduce aflatoxin effect include daily consumption of chlorophyllin or oltipraz and incorporating hydrated sodium calcium alumino-silicates into the diet. Reduction and detoxification of aflatoxin is often achieved physically (sorting, physical segregation, flotation etc.), chemically (e.g. calcium hydroxide, ammonia) and microbiologically by incorporating pro-biotics or lactic acid bacteria into the diet. Millers can use blending of less and more contaminated products to reduce the overall risk. There is need for efficient monitoring and surveillance with cost-effective sampling and analytical methods to reduce risk in Africa. Public education and awareness can sensitize the population on aflatoxin risk and its management. Key words: Aflatoxin, Sub-Saharan Africa, control measures.

182 citations

Journal ArticleDOI
TL;DR: In this article, Aspergillus, Penicillium, Fusarium, Alternaria, and Geotrichum were screened for their resistance to heavy metals and the results revealed that the majority of the isolates were resistant to Pb, Cr, Cu and Zn.
Abstract: Thirty-six micro-organisms, represented by fungi and yeasts strains, were isolated from heavy metal-contaminated sites in Tangier, Morocco Filamentous fungi isolated belonged to the genera Aspergillus, Penicillium, Fusarium, Alternaria andGeotrichum They were screened for their resistance to heavy metals The results revealed that the majority of the isolates were resistant to Pb, Cr, Cu and Zn, whereas to Cd, only the fungus Penicillium sp was able to grow The level of resistance depended on the isolate tested, as well as the site of its isolation Minimum inhibitory concentrations (MICs) for Pb2+, Cr6+, Cu2+ and Zn2+ were also determined Aspergillus and Penicillium isolates were the most tolerant to the heavy metals and exhibited strong growth, often exceeding the control (isolates grown in agar medium without heavy metals) Their MIC ranged from 20 - 25 mM for Pb, followed by 15 - 20 mM both for Cu and Zn and 10 - 15 mM for Cr These fungi have shown a high level of resistance to all metals tested, which makes them attractive potential candidates for further investigations regarding their ability to remove metals from contaminated wastewaters Key words: Metal tolerance, resistance, heavy metal, soil and water fungi, biosorption

173 citations

Performance
Metrics
No. of papers from the Journal in previous years
YearPapers
202319
202226
202158
202072
201983
2018129