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• African plant-mediated for biosynthesis silver nanoparticles. • IC 50 dose was determined by XTT analysis using MCF-7 cell line was found to be about 15 µg/mL. • Iasarifolia -mediated biosynthesis AgNPs indicated strong antibacterial activity. Nanoparticles with different types, sizes, shapes and surface chemical properties can have different biological and biomedical applications. This study aims to investigate the effect of silver synthesized by Ipomoea asarifolia (native Africa plant) extract on cancer and bacteria cells. The characteristics of synthesized silver nanoparticles were determined using UV–visible absorption spectroscopy, Fourier transforms infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Also, the effect of synthesized silver nanoparticles on the viability of cancer cells and inhibitory concentration (IC 50) was calculated. The results show silver nanoparticles have the maximum UV-visible absorption at the wavelength of about 423 nm. The TEM image showed that the silver nanoparticles are spherical with an average size of 31 nm. The results of FTIR analysis suggest that flavonoids, proteins, and phenols may be responsible for ion reduction. The results of the cell toxicity test showed that the synthesized silver nanoparticles decreased the proliferation of cancer cells, and the IC 50 was determined about 15 µg/mL. Therefore, silver nanoparticles synthesized by the extract can reduce the proliferation of cancer cells and can be considered a promising strategy in cancer treatment. The results of the antibacterial test showed that the synthesized silver nanoparticles decreased the growth of bacterial cells, and the IC 50 was determined 1 µg/mL. Therefore, silver nanoparticles synthesized by the extract can reduce the proliferation of cancer and bacterial cells and can be considered a promising strategy in cancer and infection treatment. [ABSTRACT FROM AUTHOR]

Antischistosomal effect of silver nanoparticles (AgNPs) was better by praziquantel. Hepatic granulomas were well treated by green AgNPs combined with praziquantel. Chemically prepared AgNPs plus praziquantel causes severe tegumental contractions. Isolated worms treated by green AgNPs showed tegument-attached nanoparticles. Green AgNPs were lethal to worms in a concentration of 100 µg/ml after 24 hr. Schistosomiasis is one of the most important neglected tropical diseases in Africa, caused by blood fluke, Schistosoma sp. The use of nanotechnology in the treatment of this type of disease is urgently important to avoid the unwanted side effects of chemotherapy. The present study aimed to evaluate the efficacy of green silver nanoparticles (G-AgNPs), fabricated by (Calotropis procera), comparing with both chemically prepared silver ones (C-AgNPs) and Praziquantel (PZQ) treatments. The study included in vitro and in vivo evaluations. In in vitro study, 4 groups of schistosome worms were exposed to treatments as follows: the first one with a dose of PZQ (0.2 µg/ml), the 2nd and 3rd groups with different concentrations of G-AgNPs and C-AgNPs, respectively and the last one act as a negative control group. In in vivo study, six groups of mice were infected and then treated as follows: the first one with a dose of PZQ, the second with G-AgNPs, the third with C-AgNPs, the fourth with G-AgNPs plus a half dose of PZQ, the fifth with C-AgNPs accompanied by a half dose of PZQ, and the last group acted as a positive control group. The parasitological (worm burden, egg count & oogram) and histopathological parameters (hepatic granuloma profile) were used to evaluate antischistosomal activities in experimental groups. Additionally, the subsequent ultrastructural alterations were observed in adult worms using scanning electron microscopy (SEM). Transmission electron microscopy analysis showed that G-AgNPs and C-AgNPs have 8–25 and 8–11 nm in diameter, respectively, besides, fourier transform infrared analysis (FTIR) revealed the presence of organic compounds (aromatic ring groups) which act as capping agents around the surfaces of biogenic silver nanoparticles. In in vitro experiment, adult worms incubated either with G-AgNPs or C-AgNPs at concentrations higher than 100 µg/ml or 80 µg/ml, respectively, showed full mortality of parasites after 24 h. In the infected treated groups (with G-AgNPs plus PZQ & C-AgNPs plus PZQ) showed the most significant reduction in the total worm burdens (92.17% & 90.52%, respectively). Combined treatment with C-AgNPs and PZQ showed the highest value of dead eggs (93,6%), followed by G-AgNPs plus PZQ-treated one (91%). This study showed that mice treated with G-AgNPs plus PZQ significantly has the highest percentage of reduction in granuloma size and count (64.59%, 70.14%, respectively). Both G-AgNPs plus PZQ-treated & C-AgNPs plus PZQ treated groups showed the highest similar values of reduction percentage of total ova count in tissues (98.90% & 98.62%, respectively). Concerning SEM, G-AgNPs-treated worms showed more variability in ultrastructural alterations than G-AgNPs plus PZQ-treated one, besides, worms treated with C-AgNPs plus PZQ exhibited the maximum level of contractions or (shrinkage) as a major impact. [Display omitted] [ABSTRACT FROM AUTHOR]

Leishmaniasis is a major health issue that affects people all over the world, producing considerable morbidity and mortality in Asia, Africa, and the Americas, and existing treatments have significant side effects. Nowadays, the development of nanoscale materials such as biogenic silver nanoparticles has attracted much medical attraction. In this study, AgNPs were synthesized from leaf extract of Artemisia aucheri. Biosynthesized AgNPs were analyzed by UV–visible spectroscopy, dynamic light scattering and zeta potential, fourier transform infrared spectroscopy and field emission scanning electron microscopy. Biosynthesized AgNPs were examined for anti-leishmanial and antibacterial activity. The in vivo study was conducted by treating the L. major infected BALB/c mice with quercetin/ artemisia-capped silver nanoparticles ointment topically for 21 consecutive days. The in vitro and in vivo results showed that the ointment containig quercetin/artemisia-capped silver nanoparticles have the potential to decrease inflammatory responses and enhance wound healing with granulation tissue formation compared to the untreated group. Therefore, biogenic nanoparticles are safe, eco-friendly, and easy to synthesize and could be considered as an alternative regimen for treatment of L. major. Graphical Abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

A novel protocol is developed for the first time for synthesis of Silver Nanoparticles (Ag-NPs). Ag-NPs were biologically synthesised using Pearl Millet (Pennisetum glaucum) husk. The Ag-NPs were investigated for their antimicrobial property against algae, and further Ag-NPs doped charcoal was explored for catalytic oxidation of benzyl alcohol in the presence of hydrogen peroxide selectively to benzaldehyde. The antimicrobial property of the Ag-NPs was tested by incubating freshwater algae in an Ag-NP solution, and the chlorophyll concentration measured periodically. The UV–Vis Spectroscopy analysis of Ag-NPs revealed a Surface Plasmon Resonance peak at 429 nm. Scanning and Transmission Electron Microscopy showed spherical shaped and poly-dispersed nanoparticles with an average size of 17 nm. Fourier Transform Infrared Spectroscopy affirmed the role of Pearl Millet extract as a reducing and capping agent of silver ions. Incubation of algae with Ag-NPs resulted in a 41.31% reduction in chlorophyll concentration. HPLC confirmed the oxidation of benzyl alcohol to benzaldehyde, with 90% conversion. The study concluded that biologically synthesised Ag-NPs are toxic to algae and can be used for algae control in wastewater treatment, and as Ag NPs doped on the charcoal catalyst for catalytic oxidation of benzyl alcohol to form benzaldehyde. With cleaner production concept, this protocol addresses treating the algae contaminated water with Ag-NPs. An eco-friendly, economical process is developed for Namibia/Africa, which is stressed by water shortage. Further, the efficacy of Ag-NP doped charcoal as a catalyst for selective oxidation of benzyl alcohol to benzaldehyde is established. [Display omitted] • This work highlights about Ag NPs synthesised from Pennisetum Glaucum rice husk by biological method. • A novel method developed for synthesizing AgNPs from Pennisetum Glaucum for the first time a concept of Cleaner Production. • Ag NPs for treatment of water contaminated with Algae. • Antimicrobial activity of AgNPs on algae. • AgNPs doped on charcoal for selective oxidation of benzyl alcohol to benzaldehyde. [ABSTRACT FROM AUTHOR]

The prompt treatment of burn wounds is essential but can be challenging in remote parts of Africa, where burns from open fires are a constant hazard for children and suitable medical care may be far away. Consequently, there is an unmet need for an economical burn wound dressing with a sustained antimicrobial activity that might be manufactured locally at low cost. This study describes and characterizes the novel preparation of a silver nitrate-loaded/poly(vinyl alcohol) (PVA) film. Using controlled heating cycles, films may be crosslinked with in situ silver nanoparticle production using only a low heat oven and little technical expertise. Our research demonstrated that heat-curing of PVA/silver nitrate films converted the silver to nanoparticles. These films swelled in water to form a robust, wound-compatible hydrogel which exhibited controlled release of the antibacterial silver nanoparticles. An optimal formulation was obtained using 5% (w/w) silver nitrate in PVA membrane films that had been heated at 140 °C for 90 min. Physical and chemical characterization of such films was complemented by in vitro studies that confirmed the effective antibacterial activity of the released silver nanoparticles against both gram positive and negative bacteria. Overall, these findings provide economical and simple methods to manufacture stable, hydrogel forming wound dressings that release antibiotic silver over prolonged periods suitable for emergency use in remote locations. [ABSTRACT FROM AUTHOR]

Introduction: We previously described the manufacture and characterization of hydrogel forming, thin film, anti-infective wound dressings made from Poly Vinyl Alcohol (PVA) and silver nanoparticles, crosslinked by heat. However, these films were designed to be inexpensive for simple manufacture locally in Africa. In this new study, we have further developed PVA dressings by manufacturing films or electrospun membranes, made from blends of PVA with different degrees of hydrolyzation, that contain silver salts and degrade in a controlled manner to release silver in a sustained manner over 12 days. Methods: Films were solvent cast as films or electrospun into nanofibre membranes using blends of 99 and 88% hydrolyzed PVA, containing 1% w/w silver sulphadiazine, carbonate, sulphate, or acetate salts. Dissolution was measured as weight loss in water and silver release was measured using inductively coupled plasma (ICP) analysis. Results: Cast films generally stayed intact at PVA 99: PVA 88% ratios greater than 40:60 whereas electrospun membranes needed ratios greater than 10:90. Films (40:60 blend ratio) and membranes (10:90) all released silver salts in a sustained fashion but incompletely and to different extents. Electrospun membranes gave more linear release patterns in the 2–12 day period and all salts released well. Conclusion: Blended PVA cast films offer improved control over hydrogel dissolution and silver release without the need for high temperature crosslinking. Blended PVA electrospun membranes further improve membrane dissolution control and silver release profiles. These blended PVA films and membranes offer improved inexpensive systems for the manufacture of long lasting anti-infective hydrogel wound dressings. [ABSTRACT FROM AUTHOR]