Antiplasmodial activities of crude Moringa oleifera leaves extracts on chloroquine sensitive Plasmodium falciparum (3D7)

The antimalarial efficacy of crude hexane, methanol and lyophilized aqueous Moringa oleifera leaf extract was evaluated on chloroquine sensitive (CQS) strain of Plasmodium falciparum (3D7) in vitro, with a view to validate traditional use of M. oleifera as antimalarial. A dose dependent suppression of parasite growth was observed for all extracts, at microgram per mills (µg/mL) concentrations. At the lowest concentration of extract (6.25 µg/mL), the hexane, methanol and lyophilized aqueous extracts showed 63.52%, 71.42% and 60.65% suppression of plasmodium growth respectively. The extracts showed potent biological activity at the highest concentration of extract, with a strong inhibition of plasmodium growth (71.31%, 83.06% and 80.36%) observed for the hexane, methanol and lyophilized aqueous extracts. Although some extracts are observed to be more potent than others, all extracts are observed to be biologically active against the 3D7 strain of P. falciparum (Hexane extract IC50 = 3.36 µg/mL; methanol IC50 = 3.44 µg/mL and aqueous IC50 = 4.09 µg/mL respectively). The antiplasmodial activities observed may well be attributed to the presence of phenols, tannins, alkaloids and flavonoids in all solvent extracts. Key words: Antiplasmodial, Moringa oleifera, Phytochemical screening, Plasmodium falciparu

Antibacterial potency of garlic extract against certain skin pathogenic bacteria

The antibacterial potency of garlic extract (Allium sativum) against gram positive and gram negative skin pathogenic bacteria including; Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, and Pseudomonas aeruginosa were studied using agar well diffusion and broth dilution assays. Agar well diffusion assay for aqueous garlic extract (AGE) was characterized with zones of inhibition ranging from 4.40 – 3.80cm, 4.13 - 3.57cm, 3.40 – 2.67cm for S. aureus, S. epidermidis and Strep. pyogenes, respectively, however, Ps. aeruginosa had lesser zone of inhibition ranging from 2.32 – 1.55cm. Studying the antibacterial potency of AGE against the selected isolates, revealed that it is affected by temperature of storage. Current results showed that storage of AGE at low temperature of - 20oC, does not affect its potency, however, its potency was slightly lost at high temperatures above 37oC. The broth dilution test was performed to investigate the Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the AGE against the bacterial isolates at 37oC. Investigating the activity of AGE loaded on Gel dressing revealed that it can have potency when applied on patients with Staphylococcal skin infections. Findings from this study encourage and support the use of AGE in treating bacterial skin infections especially in developing countries like Africa, as it is available, economic and have no side effects

A Review on Plants and Microorganisms Mediated Synthesis of Silver Nanoparticles, Role of Plants Metabolites and Applications

Silver nanoparticles are one of the most extensively studied nanomaterials due to their high stability and low chemical reactivity in comparison to other metals. They are commonly synthesized using toxic chemical reducing agents which reduce metal ions into uncharged nanoparticles. However, in the last few decades, several efforts were made to develop green synthesis methods to avoid the use of hazardous materials. The natural biomolecules found in plants such as proteins/enzymes, amino acids, polysaccharides, alkaloids, alcoholic compounds, and vitamins are responsible for the formation of silver nanoparticles. The green synthesis of silver nanoparticles is an eco-friendly approach, which should be further explored for the potential of different plants to synthesize nanoparticles. In the present review we describe the green synthesis of nanoparticles using plants, bacteria, and fungi and the role of plant metabolites in the synthesis process. Moreover, the present review also describes some applications of silver nanoparticles in different aspects such as antimicrobial, biomedicine, mosquito control, environment and wastewater treatment, agricultural, food safety, and food packaging

Spatial distribution and ecological niche modeling of geographical spread of Anopheles gambiae complex in Nigeria using real time data

Abstract The need for evidence-based data, to inform policy decisions on malaria vector control interventions in Nigeria, necessitated the establishment of mosquito surveillance sites in a few States in Nigeria. In order to make evidence-based-decisions, predictive studies using available data becomes imperative. We therefore predict the distribution of the major members of the Anopheles gambiae s.l. in Nigeria. Immature stages of Anopheles were collected from 72 study locations which span throughout the year 2020 resulted in the identification of over 60,000 Anopheline mosquitoes. Of these, 716 breeding sites were identified with the presence of one or more vector species from the An. gambiae complex and were subsequently used for modelling the potential geographical distribution of these important malaria vectors. Maximum Entropy (MaxEnt) distribution modeling was used to predict their potentially suitable vector habitats across Nigeria. A total of 23 environmental variables (19 bioclimatic and four topographic) were used in the model resulting in maps of the potential geographical distribution of three dominant vector species under current climatic conditions. Members of the An. gambiae complex dominated the collections (98%) with Anopheles stephensi, Anopheles coustani, Anopheles funestus, Anopheles moucheti, Anopheles nilli also present. An almost equal distribution of the two efficient vectors of malaria, An. gambiae and Anopheles coluzzii, were observed across the 12 states included in the survey. Anopheles gambiae and Anopheles coluzzii had almost equal, well distributed habitat suitability patterns with the latter having a slight range expansion. However, the central part of Nigeria (Abuja) and some highly elevated areas (Jos) in the savannah appear not suitable for the proliferation of these species. The most suitable habitat for Anopheles arabiensis was mainly in the South-west and North-east. The results of this study provide a baseline allowing decision makers to monitor the distribution of these species and establish a management plan for future national mosquito surveillance and control programs in Nigeria