Chemistry Research Papers/Topics

In vivo antibacterial activity of extracts of Tithonia diversifolia against Ralstonia solanacearum in tomato

Abstract Currently, losses in crop yields caused by Ralstonia solanacearum have led to the overuse of synthetic pesticides, which are toxic and non-biodegradable hence detrimental to the environment. This study, therefore, investigated the in vivo antibacterial activity of ethanolic and hexane extracts from Tithonia diversifolia against R. solanacearum in tomatoes. Extraction was performed using the maceration method followed by evaluation of the extraction yields. During the in vivo greenho...

Synthesis, Characterization, and Evaluation of the Remediation Activity of Cissus quadrangularis Zinc Oxide Nanoparticle-Activated Carbon Composite on Dieldrin in Aqueous Solution

Abstract In this study, zinc oxide-activated carbon nanocomposite was used as the adsorbent for the remediation of dieldrin in aqueous media. Zinc oxide nanoparticles (ZNPs) were synthesized from Cissus quadrangularis (C. quadrangularis) leaf extract, and activated carbon was derived from maize cobs. Nanocomposites were formulated by mixing the ZNPs with the activated carbon in a ratio of 1 : 50. The UV-Vis spectra showed a complete reduction of Zn2+ to Zn0 with plasmon resonance bands i...

Evaluation of dyeing properties of natural dyes extracted from the heartwood of Prosopis juliflora on cotton fabric

Abstract Purpose Considered as one of the most unwanted species by the International Union for Conservation of Nature, the Prosopis juliflora plant is a noxious and invasive weed. Recent studies suggest that the heartwood of the plant has an unusually high amounts of flavonoids with potential medicinal properties and dyeing potentials. In this work, acetonic extracts were successfully valorized into a natural dye. Design/methodology/approach After extraction and optimization of dyeing condit...

Phytochemical Composition and Antibacterial Activity of Fruit Extract of Solanum incanum L. against Ralstonia solanacearum

Abstract Aims: To determine the phytochemical composition and antibacterial activity of Solanum incanum fruits against Ralstonia solanacearum. Study Design: Experimental design involving completely randomized design Place and Duration of Study: The study was conducted at department of Chemistry and Biochemistry, School of Sciences and Aerospace studies, Moi University, Kenya, between January and June 2021. Original Research Article Karanja et al.; AJACR, 9(4): 1-16, 2021; Article no.AJACR.75...

Volatile aroma chemical constituents of fruit pulp of some Kenyan varieties of mango (Mangifera indica L.)

Abstract Volatiles are key constituents of mango fruit aroma and vital in defining fruit quality besides influencing consumer preferences. In this paper, volatiles of eight Kenyan mango varieties: Ngowe, Apple, Keitt, Boribo, Tommy Atkins, Van Dyke, Sabre and Kent were collected on porapak Q adsorbent filters (mesh 40-80μm) using air entrainment kit and analyzed by Gas Chromatography (GC) and GC coupled to a Mass Spectrometer. Fifty-eight compounds, representing monoterpenes (66.1%), esters...

Ovicidal Activity of 2-Hydroxy-4-Methoxybenzaldehyde, Derivatives and Structural Analogues on Anopheles gambiae eggs

Abstract Background Effective remedies for disrupting Anopheles gambiae metamorphosis at the egg stage are crucial in suppression of the malaria vector populations that result in the reduction of disease burden. 2-Hydroxy-4-methoxybenzaldehyde (the major component of Mondia whytei roots), its derivatives, structural analogues and their blends were evaluated against the eggs of An. gambiae in the search for ovicidal compounds with potential use in mosquito control programs. Methods Mature roo...

Anti-inflammatory norhopanes from the root bark of Fagaropsis angolensis (Engl.) H.M.Gardner

Abstract Two new norhopane derivatives namely 3β,6β,22-trihydroxy-7β,11α-di[(4-hydroxybenzoyl)oxy]-21αH-24- norhopa-4(23)-ene (1) and 3β,6β,22-trihydroxy-7β-[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23)-ene (2) together with two previously reported compounds, including a norhopane, 3β,6β,11α-trihydroxy-7β-[(4-hydroxybenzoyl) oxy]-24-norhopa-4(23),17(21)-diene (3) and a norneohopane, (21αH)-24-norneohopa-4(23), 22(29)-diene-3β,6β,7β-triol 7-caffeate (4) were isolated from the...

Effect of Human Activities and Seasonal Variation on Water Quality of Nkenye (Chikuu) Stream in Chuka, Kenya

Abstract Composite water and sediment samples were taken from Nkenye stream at five different sampling stations during wet and dry seasons. Water quality parameters were analyzed using standard methods to ascertain the effect of human activities on the water quality. The variations in the physicochemical and biological parameters were observed from station to station both in the dry and wet seasons. These variations were attributed to human activities. Results showed significant seasonal var...

Effects of Zeolite X on Dissipation of Hexazinone from Agricultural Waste Waters in Western Kenya

Abstract Dissipation of hexazinone in Zeolite X treated wastewater followed pseudo first-order kinetics giving a calculated half-life of 41 days compared to a half-life of 144 days in untreated wastewater. The herbicide degraded faster (0.0067 h-1) in treated than in nonzeolite- treated wastewater (0.0027 h-1) forming products A, B, C, D and E within the first 12 h. Zeolite X effectively catalyzed the formation of product A compared to the rest. Calculated rate constants for formation of pro...

Heavy Metals and Pesticides in Marine Sediment, Seawater, and Seaplants Along the Kenya-Mombasa Coastline

Abstract Marine sediment, seawater and several species of seaplants along the Kenya- Mombasa coastal region were analyzed to determine the levels of heavy metals by AAS and EDXRF and organochlorine pesticides (OCPs) by GLC-ECD. In marine sediments, there were high levels of manganese (1100 mg/L) at Vanga, compared to other study sites. In seawater, the heavy metals were detected in levels higher than those considered as natural in the ocean and the range was 0.01–0.30 mg/L. OCPs were detec...

Use of human nails as bio-indicators of heavy metals environmental exposure among school age children in Kenya

Abstract Metal pollution and its health effects present a challenge currently facing the developing countries. Metal poisoning is usually difficult and expensive to assess or screen in these countries due to limited resources, which means that policies, guidelines, regulations and institutional managements are limited. Hair and nail as biopsy materials were suggested as more attractive biomarkers in assessing heavy metals environmental exposure. This paper deals with quantitative determinati...

Molluscicidal and antimicrobial activity of solanum aculeastrum

Abstract The methanolic extract of the fresh root bark and berries of Solanum aculeastrum showed significant activity against host snails of schistosomiasis. The berries extract was more potent with 100% snail kill at 50 ppm. Fractionation increased activity with 100% mortality at 20 ppm. The aqueous and methanolic extracts of the berries showed moderate antimicrobial activity, increasing by fractionation.

Comparative assessment of total Phenolic content in selected medicinal plants

Abstract This study was to compare the total phenolic (TP) content in extracts from eleven plant materials collected at different geographical locations in Kenya, Nigeria, and USA. These plants have been selected because the majority of them are highly pigmented, from yellow to purple, and would therefore have economic value in industries for producing antioxidants and surfactants. Two of them were collected from the industrial and domestic waste outlets. Each analysis was achieved using the...

Magnetoelectric, dielectric, and magnetic investigations of multiferroic NixCo1-xFe2O4-SryBa1-yNb2O6 composites

Magnetoelectric (NixCo1-xFe2O4)0.3-(SryBa1-yNb2O6)0.7 composites with a 0–3 connectivity and different cation stoichiometries were synthesized via a classical mixed-oxide method. XRD patterns of all ceramics show reflections of the target phases SryBa1-yNb2O6 and NixCo1-xFe2O4. The influence of stoichiometry of the ferrimagnetic and ferroelectric phase on the magnetoelectric behavior was studied on composites with composition of (NixCo1-xFe2O4)0.3-(Sr0.5Ba0.5Nb2O6)0.7 and (NiFe2O4)0.3-(SryB...

YNTHESIS, CHARACTERIZATION AND SORPTION BEHEVIOUR OF Ce-MOF FOR THE REMOVAL OF PHOSPHATE AND FLUORIDE IONS FROM AQUEOUS SOLUTION

Abstract: The wastewater treatment industry has identified the discharge of inorganic anions such as phosphate and fluoride into water as a risk to the natural environment and human health. Among various methods used to remove phosphate and fluoride anions, adsorption is widely used because of its low cost, ease of use and simplicity. In this study, cerium-based organic metal frameworks was proposed as adsorbent to remove phosphate and fluoride ions from water.. The aim of this work was to s...


16 - 30 Of 625 Results