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Oberholster PJ, Botha A-M* and Grobbelaar JU
Abstract: Cyanobacteria are one of the earth’s most ancient life forms. Evidence of their existence on earth, derived from fossil records, encompasses a period of some 3.5 billion years in the late Precambrian era. Cyanobacteria are the dominant phytoplanton group in eutrophic freshwater bodies worldwide. They have caused animal poisoning in many parts of the world and may present risks to human health through drinking and recreational activity. Cyanobacteria produce two main groups of toxin namely neurotoxins and peptide hepatotoxins. They were first characterized from the unicellular species, Microcystis aeruginosa, which is the most common toxic cyanobacterium in eutrophic freshwater. The association of environmental parameters with cyanobacterial blooms and the toxicity of microcystin are discussed. Also, the synthesis of the microcystins, as well as the mode of action, control and analysis methods for quantitation of the toxin is reviewed.[...] Read More.
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Berhanu Abraha Tsegay
Abstract: The genetic modification of plants by gene technology is of immense potential benefits, but there may be possible risks. The advantages and social concerns of plant gene technology are discussed.[...] Read More.
Keywords: Gene technology, genetically modified plant, agriculture.
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KORIR Elena Doudoladova*, OCHIENG David, NDIRITU Douglas
Abstract: Hepatic alcohol dehydrogenase and aldehyde dehydrogenase are major enzymes in the metabolism of exogenous ethanol. These enzymes are polymorphic and are involved in alcohol drinking and risk of alcoholism in some world populations. Three hundred and seventy one samples of hair root lyzates from five Kenyan communities were screened for ADH 2, ADH 3 and ALDH 2 polymorphisms via isoelectric focusing. Additional information on alcohol drinking behaviour, alcohol intake, frequency of alcohol drinking, preference of alcoholic drinks, and alcohol dependence was collected via interview and questionnaire. SAS JPIN statistical program was used to analyze obtained data using chi-square, Anova and t-tests. The results showed that ADH 2*2, ADH 3*1 and ALDH 2*2 alleles do not have protective properties against risk of alcoholism in the selected Kenyan populations. Other factors than ADH and ALDH polymorphisms interfered in the protective mechanism of the latter alleles against excessive alcohol drinking.[...] Read More.
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Muluvi GM*, Sprent JI, Odee D, Powell W
Abstract: The mating system in plant populations is influenced by genetic and environmental factors. Proper estimates of the outcrosing rates are often required for planning breeding programmes, conservation and management of tropical trees. However, although Moringa oleifera is adapted to a mixed mating system, the proportion of selfing has not been previously estimated. The current work therefore, shows the use of AFLP markers in a mating system study of M. oleifera seed orchard. Data revealed a mixed mating system with a multilocus outcrossing rate (tm) of 0.74. It further demonstrated that AFLP markers, though dominant with a lower information content than co-dominant markers are adequate for the study of the mating system in plant populations. The 26% selfing observed in M. oleifera can lead to overestimation of the proportion of additive genetic variance and appropriate adjustments are therefore required. However, the presence of selfing as well as early sexual maturity (6 months to 1 year) in M. oleifera provides an opportunity for developing inbred lines and hybridisation. Additionally, in designing M. oleifera seed orchards, randomisation and minimum distance between related individuals need to be worked out to maximise cross-fertilisation among unrelated clones and minimise selfing or mating among related ramets.[...] Read More.
Keywords: Moringa oleifera, mating system, outcrossing rates, amplified fragment length polymorphism.
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N. Kameswara Rao
Abstract: Conservation and sustainable use of genetic resources is essential to meet the demand for future food security. Advances in biotechnology have generated new opportunities for genetic resources conservation and utilization. Techniques like in vitro culture and cryopreservation have made it easy to collect and conserve genetic resources, especially of species that are difficult to conserve as seeds. While technologies like enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) have provided tools that are more sensitive and pathogen specific for seed health testing, tissue culture methods are now widely applied for elimination of systemic diseases such as viruses for safe exchange of germplasm. Molecular markers are increasingly used for screening of germplasm to study genetic diversity, identify redundancies in the collections, test accession stability and integrity, and resolve taxonomic relationships. The technology is also expanding the scope of genetic resources utilization.[...] Read More.
Keywords: Biotechnology, conservation, plant genetic resources.
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Agricultural genomics and sustainable development: Perspectives and prospects for Africa
Abstract: The genomes of various organisms have now been fully sequenced, including human and representative microbial, insect, animal and plant genomes. The research challenge in the post-genome era is to establish how genes and proteins function to bring about changes in phenotype. Some of these phenotypes, and products obtainable through modern biotechnology, are of crucial importance within the context of sustainable development of African economies. The greatest ultimate impact will be in agricultural genomics, especially for marker assisted selection and breeding programs in crop and animal agriculture, development of animal disease diagnostics and vaccines, crop genetic engineering to overcome abiotic and biotic stresses and for improvement of the nutritional quality of major food staples. It is imperative that African countries become key players in the “gene revolution” since the cost of leaving them behind may be higher than the cost of empowering them to become players in mastering and benefiting from biotechnology. This paper highlights the potential impact of the latest advances in modern biotechnology, including genomics and bioinformatics, on sustainable development, in line with the goals of the New Partnership for Africa's Development (NEPAD). These include acceleration of economic growth, eradication of widespread and severe poverty and efforts to halt the marginalization of Africa in the globalization process.[...] Read More.
Keywords: Genomics, modern biotechnology, agriculture, sustainable development, Africa.
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Nyerhovwo J. Tonukari
Abstract: Scientific inquiry thrives only in a society that fosters the free flow of ideas and information. The power of online (internet) publication in democratizing science and incorporating scientists from developing countries into the scientific community is profound. The desired and obvious properties of scientific publishing such as accessibility, economy, quality, innovation, and retrieval can be more readily achieved with electronic methods. Online publication is much cheaper and faster, and that is major reason Africa should embrace the open access model for research communication. An open access African journal (the African Journal of Biotechnology) is evaluated.[...] Read More.
Keywords: Open access, African Journal of Biotechnology, research communications.
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Daniel K. Masiga* and Raphael D. Isokpehi
Abstract: Genome science is a new type of biology that unites genetics, molecular biology, computational biology and bioinformatics. The availability of the human genome sequence, as well as the genome sequences of several other organisms relevant to health, agriculture and the environment in Africa necessitates the development and delivery of several types and levels of training that will enhance the use of genome data and the associated computational resources. A survey of initiatives that provide opportunities for training in genome science is presented. Current efforts to increase the ability of African scientists to computationally process and analyse genomic and post-genomic data have the potential to produce excellent scientists who perform cutting-edge, hypothesis-based research, and who will accelerate the continent’s scientific and technological development.[...] Read More.
Keywords: Bioinformatics, computational biology, genome science, networking.
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S. Parvez*, Z. Mukhtar, F. Rashid, M.I. Rajoka
Abstract: A β-glucosidase genomic DNA from Cellulomonas biazotea NIAB 442 was isolated and coated onto tungsten microprojectiles for direct transformation of the gene into Saccharomyces cerevisiae. Transformation of β-glucosidase into S. cerevisae conferred the ability to hydrolyse esculin and cellobiose, indicating that the gene is expressed in the bombarded yeast.[...] Read More.
Keywords: Biolistic transformation, β-glucosidase, Cellulomonas biazotea, Saccharomyces cerevisiae.
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Thereza Christina Vessoni Penna*, Marina Ishii, Luciana Cambricoli de Souza , Olivia Cholewa
Abstract: The recombinant green fluorescent protein (GFPuv) was expressed by transformed cells of Escherichia coli DH5-α grown in LB/amp broth at 37oC, for 8 h and 24 h. To evaluate the effectiveness of different parameters to improve the expression of GFPuv by E. coli, four variable culturing conditions were set up for assays by a fractional factorial (24-1) design at two levels: (i) the effect of storing (24-48 h) the seeded broth at 4oC prior to incubation at 37oC; (ii) the effect of agitation speed (100-200 rpm); (iii) the final concentration (0.05-0.5 mM) of IPTG (isopropyl–β-D-thiogalactopyranoside) and (iv) the addition of IPTG at set cell densities (OD660 0.01-0.8). GFPuv was extracted from cells by the three phase partitioning method (TPP) and further purified with a methyl HIC column. The cultures grown at 37oC/24 h provided the highest yields of GFPuv under the conditions: (i) pre-storage at 4oC/24 h; (ii) agitation speed at 100 rpm; (iii) 0.5 mM IPTG and (iv) IPTG addition at OD660~0.01. On the other hand, at 37oC/ 8 h, GFPuv expression was dependent upon agitation of broth cultures at 200 rpm and the IPTG addition at the beginning of the growth exponential phase.[...] Read More.
Keywords: Green fluorescent protein (GFPuv), Escherichia coli DH5-α, growth kinetic parameters, expressed GFPuv kinetic parameters, three phase partitioning extraction (TPP).
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