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ABSTRACT
Abstract: African nightshades (Solanum scabrum) are one of indigenous vegetables widely consumed in Kenya. Yield losses due to aphids are estimated to about 84-96% in Kenya. Aphids have developed resistance to synthetic pesticides. There is need to identify ecofriendly alternatives such as the use of botanicals like pyrethrum which are cheaper and safe to protect this potential vegetable specifically against insect pests which includes aphids, black-ants and white flies that severely reduce the yields. Plants secondary metabolites constitute a major source of bioactive substances. Pyrethrum extracts contain active ingredients which block the voltage gated sodium channels in nerve axon insects, resulting in a knockdown effect, hyperactivity, and convulsions hence death of insect pests. Little has been documented on the anti-aphid effect of pyrethrum leaf, flower and root extracts on aphids. Information on secondary metabolites in pyrethrum flower, root and leaf extracts is lacking. The objectives of this study were to determine the phytochemical constituents in pyrethrum flower, leaf and root parts and to determine the effect of different concentration levels of pyrethrum extracts on aphids affecting S. scabrum. The study was conducted at Maseno University farm. A field experiment was laid in Randomized Complete Block Design with three replications. Five treatments consisting of 0%, 33%, 67% and 100% pyrethrum flower, root and leaf extracts and duduthrin were applied. Phytochemical screening of extracts was carried out. Solanum scabrum seeds were locally sourced from the Botanic Garden, Maseno University, germinated and raised in 3m by 1m plots caged with mosquito net. After four weeks the seedlings were thinned to 9 seedlings per plot. Aphids (Aphis fabae) were obtained from International Center of Insect Physiology and Ecology- Nairobi were reared then introduced to every seedling (10 aphids) in all plots. Aphid population was determined weekly on leaves and by use
ABSTRACT
Abstract: The study of gene expression was conducted by 8 Acinetobacter baumannii isolates. This study focused on effect of the Lactobacillus casei and Lactobacillus plantarum on Gene Expression of OmpA and EpsA Genes in A. baumannii isolates. The primers for A.baumannii targeting OmpA and EpsA genes are highly specific for expressing. Gene expression of OmpA and EpsA genes was quantified through Real- time PCR in A.baumannii isolates were before and after the treatment with the Lactobacillus casei and Lactobacillus plantarum, the isolates was selected that appeared highly Ct (cycle threshold) value. Ct value was determined as the point (cycle) at which the amplification plot crossed the threshold line. Eight isolates (AS-1, AS-2, AS-4, AS-5, AS-6, AS-7, AS-8 and AS-10) participated in their gene expression OmpA and EpsA genes. The qRT-PCR method has been used to examine the expression levels of the OmpA gene in Acinetobacter baumannii Isolates under the effect Lactobacillus casei and Lactobacillus plantarum. The results showed that the Lactobacillus casei and Lactobacillus plantarum increased the transcript levels of the tested gene in A. baumannii isolates with Lactobacillus casei and Lactobacillus plantarum. The results showed of (P1-P8) that OmpA gene gave a highly expression of different degrees by amplification of the gene. The Ct value of Omp A gene in the present study show the pattern of the amplification of the gene were (19.0, 23.49, 19.16, 19.14, 19.79, 20.03, 20.1 and 20.2) and folding (2.57, 0.23, 3.17, 2.59, 9.68, 5.73, 9.51 and 16.42). while (C1-C8) that OmpA gene expression recording Ct value (21.85, 21.37, 22.27, 21.83, 20.75, 20.25, 19.40 and18.59) and (1.03, 1.91,4.26,1.17,15.89,8.35,4.15 and 6.55) of folding compared to the control. The results showed of (P1-P8) that eps A gene gave a decrease expression of different degrees by amplification of the gene. The Ct value of eps A gene in the.....................
ABSTRACT
Abstract: The adequately iodized salt consumption is significant in the prevention and the fight against the disorders due to the iodine deficiency (TDCI).The objective of this study was to evaluate the iodine content of cooking salts in the households, in order to assess its quality during the conservation. With this intention, a taking away of 500 G table salt was carried out trades about it and preserved under the conditions imitating that of the households. The results obtained showed a loss of iodine during its conservation. Indeed, of the first week at the fifth week of conservation, salt recorded a significant loss of its iodine content of 12, 67 ppm is 21, 71 % of its starting iodine content. This work suggests that salt must be consumed as soon as possible to avoid an exposure to an iodic deficiency of the population.
ABSTRACT
Abstract: Combining ability of inbred lines is important information in maize(Zea mays.L) hybrid breeding programs to incorporate genotypes from various germplasm sources. This study was conducted with germplasm developed using double haploid technology (DH) lines. Sixty-six F1 crosses resulted from diallel crosses of 12 maize inbred lines with four standard checksArgane (AMH800), Kolba (AMH853), Jibat (AMH851) and Wenchi (AMH850) were evaluated based on partial diallel meeting fashion and its relative analysis to estimate general combining ability (GCA) and specific combining ability (SCA) for yield and yield related traits using alpha-lattice design with three replications during the 2017 cropping season at Ambo, Holeta and Kulumsa Agricultural research center of Ethiopian Institution of agricultural Reseach Institution. Analysis of variance showed that mean squares due to entries were significant for most of the traits studied, such as grain yield, thousand kennels weight, days to silking, ear per plant, plant height, ear height, husk cover, ear rot, ear aspect, plant aspect, kernel rows per row, ear length and ear diameter .Genotypes x environment interactions showed highly significant difference at (p<0.01) for most traits but significant (p<0.05) for grain yield.Mean squares due to crosses were significant (p<0.05) at two locations (Holeta and Kulumsa). Alleles at a locus can have an effect on the trait by themselves but can also affect the phenotype through interactions with other alleles the so called non- additive effect, while when allele of a single gene (in heterozagote )combine so that their combined effects equal the sum of their individual effects called additive gene action. GCA and SCA mean squares revealed significant (p<0.05) differences for grain yield and most yield related traits in all location and across location. Inbred lines P2, P9 and P12 were good general combiners as these lines showed significant and positive..................
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Abstract: The major advantage of using plant extracts for silver nanoparticle synthesis is that they are easily available, safe, and nontoxic in most cases, have a broad variety of metabolites that can aid in the reduction of silver ions, and are quicker than microbes in the synthesis. The main mechanism considered for the process is plant-assisted reduction due to phytochemicals. In present we had selected two plant - Ziziphus mauritina commonly known as Indian jujube (Ber) and Coriandrum sativum commonly known as coriander for the phytochemical screening, nanoparticle synthesis and antibacterial activity against Kliebsella pneumonia, Clostridium per fringes, Citrobacter freundii and Staphylococcus aureus bacteria. All the bacteria selected in this study are highly and drug resistant. Potency of these plant extract against selected bacterial culture increases with formulation of nanoparticles .When compared with free extract in terms of zone of inhibition exhibited by bacterial culture. Zeta potential analysis of nanoparticles confirms that all the nanoparticles are of size loss them 100 nm. Stability of nanoparticles up to 15 days was observed which confirms the method of preparation of nanoparticle is stable and successful. Research finding confirms the format and stable nature of nanoparticles, which make them, potential and significant in drug delivery agent.
ABSTRACT
Abstract: The study was conducted to find out the effects of Moringa oleifera leaves and seeds as a supplementary feed on the growth performance of all-male tilapia. The main objectives of the study were to determine effects of the supplementary feed (leaves + normal feed, seeds + normal feed, leaves + seeds + normal feed) on all male tilapia in terms of their average standard length, total length, standard width, total width and weight. The parameters for each of the treatments were measured fortnightly over the entire eight weeks period. The sample covered a total population of 260 fishes - 20 each from the hapa and 60 from each of the 4 ponds. The results revealed significant differences among the treatments (normal feed, leaves + normal feed, seeds + normal feed, leaves + seeds + normal feed) used on the parameters measured (average: standard length, total length, standard width, total width and weight) at (p < 0.05). The results clearly demonstrated that the seeds recorded higher (best growth) performance in terms of the parameters measured than all the other treatments administered. This was followed by combination of seeds and leaves with the normal feed only recording the least performance.
ABSTRACT
The ability to utilize Typha grass as a potential substrate for bioethanol production was analyzed in this research, the sample of Typha grass collected from Kware Lake was pretreated by autoclaving after it was initially dried and grounded into powdered form. The pretreated samplewas enzymatically hydrolyzed using Aspergillus niger for 7 days. The hydrolyzate was used to produce bioethanol by fermentation using Saccharomyces cerevisiae which was determined by HPLC analysis.The results indicated that pretreated Typha grass sample that was having higher lignin and hemicellulose composition of 28.15 % and 30.0 % was reduced to 14.29 % and 7.8 % respectively. Also, the α-cellulose composition was increased to a highest composition of 23.2 % from a lowest composition of 10.0 %. The pretreated sample that was hydrolyzed produced a highest reducing sugar yield of 19.14 g/L and the fermented hydrolyzate produced a bioethanol concentration of 2.07 % at day 6 of the fermentation period. From the results of this research, it is concluded that bioethanol can be produced from Typha grass and pretreatment can lessen cristallinity and expose cellulose thereby escalating reducing sugar yield for maximum bioethanol production