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Silver nanoparticles (AgNPs) were biosynthesized at room temperature under sunlight irradiation, using the extract of Jasminum subtriplinerve Blume (JS) leaf as a reducing agent and also stabilizers. The obtained AgNPs were thoroughly characterized by UV–Vis Spectroscopy, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared spectroscopy (FT-IR) and their antibacterial property was evaluated on five types of bacteria by implementing the minimum inhibitory concentration test (MIC) and the zone of inhibition test. No antibacterial activity was observed in the JS extract compared to the AgNPs; meanwhile, AgNPs exhibited effective antibacterial activity against all bacteria with an average diameter of inhibition zones of over 10.0 mm and the minimum inhibitory concentration of 33.08 µg/mL (higher inhibiting activity against gram (−) bacterial than that of gram (+) bacterial).

In this work, the green synthesis of silver-silver chloride nanoparticles (Ag@AgClNPs) has been used the plant leaf extract of Chromolaena odorata (C. odorata) as a reducing and capping agent. The effects of parameters on the formation of Ag@AgCl nanoparticles (Ag@AgClNPs such as the ratio of C. odorata raw material/water, the extraction temperature, the extraction duration, and the volume ratios of AgNO3 solution and C. odorata extract have been studied. The obtained Ag@AgClNPs sample was characterized by ultraviolet visible spectroscopy, X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy. UV–visible absorption studies revealed surface plasmon resonance peak around 420‒450 nm, confirming the presence of Ag@AgClNPs. The average particle size was approximately 15.2 nm. The antibacterial activity of Ag@AgClNPs was carried out by the agar well diffusion method and the determination of the minimum inhibitory concentration that showed high toxicity against the gram-negative bacteria (Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa) and the gram-positive bacteria (Bacillus cereus and Staphylococcus aureus).

A cost-effective and green technique was performed for the synthesis of silver nanoparticles (AgNPs) from a plant resource using Citrus maxima peel (CMP) extract as a reducing agent. The formation of AgNPs was confirmed by UV-Vis Spectroscopy at the wavelength range of 400−500 nm. The optimized conditions for the AgNPs synthesis using CMP extract as a reducing agent were determined. At these conditions, the X-ray diffraction (XRD) and the high-resolution transmission electron microscopy (HRTEM) results revealed the face-centered cubic structure of AgNPs had a highly crystalline with the particle size in a range of 10−20 nm. The Fourier transform infrared spectroscopy (FT-IR) demonstrated the presence of flavonoid, terpenoid, phenolic, and glycosides in phytochemical compositions of CMP extract which can act as the reducing agents for AgNPs formation. The antibacterial effect of the AgNPs was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA) by implementing the minimum inhibitory concentration (MIC), minimum batericidal concentration (MBC), and the zone of inhibition tests. The AgNPs exhibited effective antibacterial activity against bacteria with an average diameter of inhibition zones of 11.7 mm, the MIC of 8.27 µg/mL, and the MBC of the 16.54 µg/mL.

This work proposed a zero waste approach based on microwave (MW) extraction combining hydrodiffusion and gravity for preserving all valuable compounds in the form of dried ginger, ginger essential oil (EO), and juice. A rotatable apparatus was developed from a domestic MW oven to ensure a uniform exposure of the material, resulting in a uniform dried ginger product with EO content more than 0.33% and moisture content less than 10%. The optimum conditions of MW density and energy, which were determined using response surface methodology, are 1 W/g and 1 Wh/g, respectively. They are much lower comparing with that required for hydrodistillation (HD). Significant difference in extraction yield obtained by MW extraction (0.6384 ± 0.0195) and HD (1.1939 ± 0.0679) was observed; however, the quality of EO derived from MW extraction in terms of antibacterial activity was higher than that of the one derived from HD, whereas the physical properties of both EOs were similar. PRACTICAL APPLICATIONS: In this study, the applicability of microwave (MW) extraction combining hydrodiffusion and gravity for ginger processing to produce dried ginger, ginger essential oil (EO), and juice without generating waste was confirmed. Although the EO yield obtained by the proposed extraction method is smaller than that obtained by hydrodistillation (HD), it was proved to be greener and more efficient than HD in terms of extraction time, EO preserving capability, resources’ consumption, and waste generation. In addition, the EO derived from MW extraction was observed to be more active in antibacterial activity due to its high content of oxygenated and monoterpene compounds. Moreover, this modified rotatable apparatus, which was simply developed from a cheap domestic MW oven to ensure uniform dried product, could be considered technically and economically feasible for actual deployment at small‐scale processing unit.