Annual Research & Review in Biology

This study revisits antibiotic resistance as a source of evolutionary development in pathogenic bacteria. By taking a molecular phylogenetic approach to this inquiry, I seek to find homologous correlations in antimicrobial resistance gene families across a broad spectrum of bacteria, as to identify the possible acquisition of those genes through divergent events in evolutionary context. In order to test this, I examine the various degrees of genetic similarity in two antimicrobial resistance genomic datasets, namely aadA1 & aadA2 aminoglycoside resistance genes, among bacteria that occur in a multitude of environments. Moreover, the results from phylogenetic analysis suggests that pathogenic antibiotic resistance for aadA1 & aadA2 aminoglycoside resistance genes may have been acquired through evolutionary events with a common ancestor of a soil-dwelling bacterium.

Aim and Place of Work: UNICEFs assisted Water, Sanitation and Hygiene (WASH) programme is one of the intervention strategies to improve access to safe water, sanitation and good hygiene in developing countries. As 2015 MDG goals deadline approaches, assessment of progress and evaluation of these interventions are unknown in most states in Nigeria. Therefore an independent evaluation of UNICEF’s assisted WASH programme was conducted between March and August 2014 in Ogun State, Nigeria,

Methodology: Well structured interview guides were used to obtain basic information on history, range of activities, target population and challenges of the WASH intervention from the state implementing agency. Cumulative achievements reports of the agency were also retrieved for data extraction. Spot checks assessments of interventions were made to schools benefitting from WASH programme within the pilot local government area of the state. Conditions and adequacy of WASH interventions were assessed using WHO/UNICEF recommended guidelines. Data obtained were uploaded and analyzed using SPSS 20.0 software for descriptive statistics. 

Results and Discussion: Findings showed that no new water source was provided since 2006 through the assisted programme. UNICEF only assisted the state in the rehabilitation of already existing water sources, hence water coverage rate stagnated at 43% since then. The rise in the states sanitation coverage in 2012 from 32% to 36% was due to the additional provision of sanitary resources to schools, markets and health centre’s by UNICEF’s assisted WASH programme. These coverage rates are unsatisfactory and may not meet the universal MDG target goal of 2015. Spot assessments to intervention schools also shows inadequacy, poor coverage and poor condition of WASH facilities.

Conclusion: Therefore, scaling up of intervention projects and monitoring of adequacy and conditions of interventions are important, requiring funding and resource allocation.

Providing products that beyond a high nutritional value brings health benefits to consumers is a major challenge to food industry. Functional foods, including prebiotics and probiotic as components, are the protagonists to promote these advantages. Aloe vera is a medicinal plant well characterized in terms of its chemical composition and therapeutic properties. Taking into account these characteristics Aloe vera represents an excellent natural source of prebiotics, as well as a substrate for lactic acid bacteria fermentation. Thus a symbiotic drink using Aloe vera as the main ingredient and lactic acid bacteria as probiotics with significant benefits to human health might represent a promising product to develop.

Introduction: Viruses have been identified as the main etiologic agents of both zoonoses and emerging infectious diseases (EIDs) and various species of wild fauna can be involved in the maintenance of these diseases. The very wide variety of bats, together with their ability to adapt to different environments and fly long distances, means that these animals are currently one of the main reservoirs for zoonoses and EIDs. For these reasons the correct identification of different bat species is essential.

Aims: This paper describes the genetic identification of 56 samples isolated from different bat species.

Methodology: Sequencing and phylogenetic analysis of the mitochondrial DNA cytochrome b (mtDNA cyt-b) gene. 

Results: Four families (Molossidae, Vespertilionidae, Noctilionidae and Phyllostomidae), twelve genera and nineteen different species of bats were identified, and the Basic Local Alignment Search Tool (BLAST) was used to confirm species identity.  The phylogenetic tree constructed revealed two main clusters (1 and 2), both consist in two subclusters.

Conclusions: Our results were concordant with those obtained by morphometric identification and genetic identification carried out by other authors, showing that the method described here can be used as an effective alternative to, or in combination with, morphometric identification of bats.

African catfish larvae do not have fully developed digestive system at onset of first exogenous feeding. Live feed like artemia have been used more than dry diets but is also costly. The gut microbiota may be influential in larval diet utilization. We therefore made three larval feed from two commercial probiotics and tested their growth and nutritional effects on first feeding hatchlings (larvae) of African catfish. The three diets were labeled as feed 1 (F1) made up of mixtures of mixtures of Lactobacillus acidophilus, Bacillus subtilis and Lactobacillus bugaricus, feed 2 (F2) was made up of 100% Saccharomyces cerevisiae and feed 3 (F3) was made up of 50% Lactobacillus mixtures and 50% Saccharomyces cerevisiae. The control diet F4 was decapsulated artemia. African catfish hatchlings were produced by artificial dry fertilization of brooders maintained in our lab. First feeding hatchlings 48 hours post fertilization (48 h pf) were stocked in well aerated 15l plastic aquariums at density of 100 larvae aquarium-1. There were three replicate aquariums per treatment feed. The photoperiod of the larval rearing system was 12 h D: 12 h L and the light intensity were maintained at 8 lux using black nylon coverings. The hatchlings were fed to satiation 5 times daily for the whole larval period of 20 days. Survival of larvae were similar (P>0.05), for those fed with feed 1 (100% mixed lactobacillus sp), (LAB) 62.59%, feed 2 (100% Saccharomyces cerevisiae) (SAC) 57.89% and feed 4 (decapsulated artemia) 57.89%. The lowest surviving larvae were those fed with F3, 50% LAB: 50% SAC 54.67%.Weight gain was however better for larvae fed with artemia AWG 0.15 g than the rest of the treatments (P<0.05). The larvae fed with 50% LAB: 50% SAC (F3) had higher AWG 0.11 g than those fed with LAB (F1) 0.07 g and SAC (F2) 0.09 g (P<0.05). The result indicates that probiotics can be used in enhancing growth and survival of larval of African catfish. Nutritional value of probiotics is similar to live feed. Prolonged use of artemia reduces survival.

Aim: Robusta coffee growing countries of the world such as Uganda, have experienced a decline in market prices since 2002 due to changed consumer preferences for other beverages. In Uganda, where Robusta coffee is the major income earner, one practical way of ensuring that coffee prices remain competitive is to enhance quality. The aim of this study was to analyze the extent of macro and microelement densities in the soils of Robusta coffee growing Ugandan farms, their relationships with density levels in the leaf and in the green bean and their ultimate contribution in the determination of cupping and marketing qualities. This information would enable coffee producers in Uganda to make decisions on which organic and inorganic fertilizer applications are needed to alleviate coffee quality which in turn is the key determinant of world prices.

Study Design: Soil, leaf and ripe cherry samples were derived from sixty seven tagged trees in twenty three on farm locations at Kawanda and Entebbe in fields that had no fertilizer application history.

Place and Duration of the Study: This work was conducted at the National Agricultural Coffee Research Institute (NaCORRI), Uganda and the Institute of Nuclear Science and Technology, University of Nairobi, Kenya, between January 2010 and December 2013.

Methodology: Nutrient densities of potassium (K), calcium (Ca), iron (Fe), titanium (Ti), zinc (Zn), copper (Cu), boron (B), lead (Pb) and manganese (Mn) of sixty seven soil, leaf and green bean samples collected from 23 districts were measured with Energy dispersive x-ray fluorescence (EDXRF). All the samples were oven-dried at 800C for 18-20 hours and ground to about 50 mm sieve-size. Three pellets of 2.5 cm in diameter were made and irradiated with a Cd-109 radioactive source. The X-rays emitted by the elements were detected by liquid nitrogen cooled Si (Li) detector and data analyzed with the Quantitative X-ray Analysis System (XQAS/AXIL) software.

Results: The results showed that the mean concentrations of Ca, Mn, Fe and Zn were highest in the soil but lowest in green beans. K concentrations were higher in green beans than in the leaf and were lowest in the soil. In most cases, the concentrations of microelements found in the soil determined the levels in the leaf and in the green bean. Microelement availability and concentrations were influenced by the interaction between the various elements, tree age, elevation, soil texture and location.

Conclusions: Mineral element K and microelement Cu were found in their highest concentration in the green bean. Mn, Zn and B were important elements in the determination of organoleptic cup attributes whereas soil, leaf and green bean nutrient concentrations were important in determining the medium size of the bean.

Coffee Berry Disease (CBD), caused by the fungus Colletotrichum kahawae, is a major constraint that hinders Arabica coffee production in Kenya. The disease causes up to 80% coffee losses thus affecting export earnings and food security in Kenya. Colletotricum kahawae is spread by raindrop splashes on unprotected trees and excessive wetness in the coffee bush. This study assessed the specific effect of artificial shading on the development and progression of C. kahawae in a commercial farm in Riabai area of Kiambu County in Kenya. The study was formulated out of the realization that the commonly used fungicides for protecting the crop were expensive and hazardous to the environment. International legislation on chemical residue levels is also becoming stringent in most coffee consuming countries. The experiment was laid out in a three replicate Randomized Complete Block Design. There were four treatments comprising of (i) four pruned and artificially shaded coffee trees; (ii) four shaded and unpruned trees; (iii) four pruned and unshaded trees and (iv) four unpruned and unshaded trees. Data was recorded on diseased berries, losses due to physiologic fall and total losses due to both and expressed as percentage of the total berries. The data was subjected to Analysis of Variance (ANOVA) using general linear model (GLM) on COSTAT software. Treatment means were separated using Duncan’s Multiple Range Test at P≤0.05. The results showed that artificial shade significantly reduced development and progression of CBD. The major finding of this study is that shade is an important cultural practice in the management of CBD. It is recommended that growing coffee under agroforestry system where artificial shade is substituted with shade trees will be more beneficial to the small holder farmer.