Natural & Applied Sciences

Research Papers/Topics Natural & Applied Sciences

Potential Association Between Tsetse Fly And Its Endosymbionts In B-Vitamins Biosynthesis

ABSTRACT Tsetse flies are the cyclical vectors of African trypanosomes, flagellated protozoa parasites that cause sleeping sickness in man and nagana in cattle, diseases collectively known as African trypanosomiasis. Vector reduction and chemotherapy are the main strategies for controlling trypanosomiasis but their limitations necessitate improvement of current and/or development of novel methods. Tsetse has three maternally transmitted bacterial endosymbionts namely Wigglesworthia, Sodalis ...

Structure Prediction Of Matrix Metalloproteinases In Anopheles Gambiae Using Bioinformatic Tools

ABSTRACT Human malaria is the most important disease in tropical countries in terms of morbidity and mortality. Malaria transmission involves complex interactions between Plasmodium falciparum and Anopheles gambiae. For successful establishment of invasion/infection of the Anopheles gambiae midgut the parasite must overcome the immune responses of the vector. Matrix metalloproteinase (MMPs) are a family of zinc metalloendopeptidases known to disrupt subendothelial membranes, destroy tight ju...

Analysis Of Flavour And Molecular Diversity Of Kenyan Lablab Bean (Lablab Purpureus (L.) Sweet) Accessions

ABSTRACT The legume species Lablab purpureus L. Sweet grows in most tropical environments. It is used as a cover crop and green manure and provides a high–protein food for humans and livestock feed. The study was carried out to analyse flavour components and molecular diversity of Kenyan lablab accessions. Twenty four accessions from the National genebank and farmers were evaluated for odour and bitter taste intensities using sensory tests. Analysis of cyanogenic glycosides was carried out...

Estimation Of Parameters Of The Mcdonald Generalized Beta - Binomial Distribution Using Estimating Functions

ABSTRACT Recently, there has been a considerable attention on modeling overdispersed binomial data that occur in toxicology, biology, clinical medicine, epidemiology and other related fields using a class of Binomial mixture distribution. Specifically, Beta-Binomial (BB) and KumaraswamyBinomial distribution (KB) in this class have been extensively used to model the overdispersed Binomial outcomes. A new three parameter binomial mixture distribution namely, McDonald Generalized Beta-Binomial ...

Analytical Determination Of The Effects Of Phosphatic Fertilizers And Manure On Maize Yields In Acidic Soils In Kisii And Rachuonyo Districts

ABSTRACT Maize production in sub-Saharan Africa remains low and the yields are on the decline. This has been attributed to a variety of factors which include soil nutrient depletion and Striga infestation. Soil phosphorous, nitrogen and Striga hermonthica are the major constraints to maize production in Nyanza Province of Kenya. The yields are typical of low input systems ranging below 1.0 t ha-1 against a potential of 5.0 t ha-1 per season. In an attempt to overcome these constraints, field...

Relationship Between Biting Frequency And Surface Proteins Of Circum-Sporozoite And Merozoite Stages In Highlands Of Western Kenya

ABSTRACT Vector control in the highlands of western Kenya has resulted in a significant reduction of malaria vectors. This has made the current entomological parameters being used to measure transmission to become insensitive and challenging. Antibodies to the Circum-sporozoite protein (CSP) have been associated with transmission intensity and have corresponded well with EIR. The study objective was to determine the association between the level of circum-sporozoite protein and merozoite sur...

Evaluation Of Cassava (Manihot Esculenta Crantz) Germplasm For Resistance To Cassava Brown Streak Disease And Virus Elimination Using In Vitro Techniques

ABSTRACT Cassava brown streak disease (CBSD) is an important disease causing losses of up to 70% in the most susceptible cultivars. Its effects include: reduced root quality due to pitting, root constriction and necrosis, and reduced number and weight of tuberous roots. To contribute to CBSD management, a study was conducted to: (i) Screen East African cassava landraces and F1 populations for CBSD resistance; (ii) Analyse symptom expression and virus accumulation in CBSV graft inoculated cas...

Biochemical Diversity Of Tea Germplasm And Potential For Processing Of Diversified Tea Products

ABSTRACT Tea industry in Kenya forms the largest agribusiness contributing up to 4% of the country’s gross domestic product and over 26% of total foreign exchange earnings. However, significant revenue is lost when tea is sold in undiversified form. Therefore, this study aimed at determining the biochemical diversity in Kenyan tea clones and their potential for diverse product development. Samples were obtained from 197 tea clones conserved in Kericho and Kangaita substation and assayed fo...

Determination Of Cyanobacterial Toxins In Lake Naivasha, Kenya

ABSTRACT Lake Naivasha is a freshwater lake located about 80 km northwest of Nairobi and lies about 1890 metres above sea level. The freshwater system is used for drinking, washing and livestock watering by more than 600,000 people. However, declining water quality due to environmental perturbations has raised public concerns worldwide. The occurrence of blooms of cyanobacteria has become a serious problem as they produce a wide spectrum of toxins including microcystin which cause various ad...

Characterization And Antimicrobial Activity Of Tropical Basidiomycetes Fungi And Their Secondary Metabolites

ABSTRACT Microbial infections remain to be a major global public health challenge. In Kenya, these infections cause significant morbidity and mortality. Their devastating effects are majorly attributed to antimicrobial drug resistance. Nonetheless, the biodiversity and ecology of tropical Basidiomycetes fungi is an untapped source of potential bioactive compounds. Therefore, the current study aimed to isolate and test crude extracts and antimicrobial compounds from Basidiomycetes against sel...

Chemical Compositions And Antimicrobial Activity Of Amaranthus Hybridus, Amaranthus Caudatus, Amaranthus Spinosus And Corriandrum Sativum.

ABSTRACT Different communities in Kenya use a wide variety of indigenous plants for food. About 850 species of plants are used for food. To this group belong Amaranthus species that has important nutrients and a rich array of biologically active secondary metabolites. Corriandrum sativum is a leafy spice/ herb that contain volatile oils from which it derives its flavour and aroma and also antimicrobial properties. Essential oils from fresh leaves of C. sativum were extracted by hydro distill...

Cultivation of Candida utilis on Cassava Peel Hydrolysates for Single-cell Protein Production

Abstract The growth of Candida utilis NRRL Y-1084 in acid and enzymatic hydrolysates of cassava peel and on glucose in a mineral salts medium was investigated in aerobic submerged cultivation. Kinetic and stoichiometric parameters for growth were determined. The cardinal temperatures of this yeast strain were 14 °C, 33 °C and 41 °C. C. utilis exhibited no absolute requirement for growth factors, although its maximum specific growth rate (μmax) was higher in the mineral salts medium with y...

Effect Of Variety And Maturity Stage Of Cassava (Manihot Esculenta) On Flour Properties And Sensory Characteristics Of Wheatcassava Composite Bread

ABSTRACT Cassava (Manihot esculenta) grows well in Tropical and Sub-Tropical regions of Sub-Saharan Africa. It is used as a food and raw material for many industrial applications, including food, feed and starch. Cassava has several varieties whose physico-chemical properties and functional properties of flour are hardly known. The aimed at characterizing physico-chemical and functional properties of cassava flour from different varieties harvested at different maturity stages and to determi...

Effects Of Blanching Time-Temperature Combinations And Solardrying On The Nutritional And Microbial Quality Of Indigenous Leafy Vegetables In Kenya

ABSTRACT The abundance of indigenous leafy vegetables (ILVs) during rainy seasons and accompanying poor storage systems leads to high post-harvest losses (PHL). These gluts in the rainy seasons are usually followed by scarcity in the dry seasons. Currently some limited preservation is employed involving boiling of ILVs and open sun drying, a practice that is inappropriate and done under unhygienic conditions. To reduce the huge losses, a cheaper, hygienic and locally adaptable preservation m...

Investigating Contact Precipitation As A Viable Water Defluoridation Technique

ABSTRACT Fluorosis is a condition caused by excessive intake of fluoride, and is characterized mainly by mottling of teeth. A number of defluoridation techniques have been proposed, studied and even implemented in a number of countries, to varying degrees of success. Among these techniques, contact precipitation, a hybrid technique involving the use of calcium and phosphate compounds together with bone char to effect defluoridation of water has been extensively used. The mechanism of fluorid...


3826 - 3840 Of 8876 Results
@