Phyto-Synthesis, Characterization, and In Vitro Antibacterial Activity of Silver Nanoparticles Using Various Plant Extracts

Abstract

Aloe vera, Mentha arvensis (mint), Coriandrum sativum (coriander), and Cymbopogon citratus (lemongrass) leaf extracts were used to synthesize stable silver nanoparticles (Ag-NPs) by green chemistry. UV–vis spectrophotometry, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) spectroscopy techniques were used to characterize these biosynthesized nanoparticles. The data indicated that the silver nanoparticles were successfully synthesized, and the narrower particle size distribution was at 10–22 nm by maintaining a specific pH. As a short-term post-sowing treatment, Ag-NP solutions of different sizes (10 and 50 ppm) were introduced to mung bean seedlings, and the overall increase in plant growth was found to be more pronounced at 50 ppm concentration. The antibacterial activity of Ag-NPs was also investigated by disc diffusion test, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) test. The zones of inhibition (ZOI) were shown by Escherichia coli (E. coli) (1.9, 2.1, 1.7, and 2 mm), followed by Staphylococcus aureus (S. aureus) (1.8, 1.7, 1.6, and 1.9 mm), against coriander, mint, Aloe vera, and lemongrass, respectively. MIC and MBC values of E. coli, and S. aureus ranged from 7 to 8 µg/mL. Overall, this study demonstrates that Ag-NPs exhibit a strong antimicrobial activity and thus might be developed as a new type of antimicrobial agent for the treatment of bacterial infection.

New Insights on Biosynthesis of Nanoparticles Using Plants Emphasizing the Use of Alfalfa (Medicago sativa L.)

“…Te biggest disadvantage of plant extract methods is a long and complicated realization process with the need to control multiple parameters. Especially, biosynthesis with callus culture cells requires realization, on average, for 1-2 days because often the extract with the precursor is left for 24 h to reduce the metal ions [56][57][58][59]. Also, an important factor is the average growth time of seedlings, which often is 15 days [68], and the average growth time of callus culture, which lasts from 30 days [38] to 45 days [74].…”

“…Other plants used for biosynthesis also contain highly active phytochemicals and enzymes that participate in oxidation or reduction reactions [88] such as multiple vitamins [55,59], triterpenoids [45], polyphenols, carbohydrates [44], favonoids [35,54,56], such as catechins and catechin gallates [49], phytosterols, ellagic acid [47], essential oils [45], phenols, such as gallic acid, gallic acid, and quercetin [54], carbohydrates, proteins, alkaloids [44,46], glycosides, iridoid glycosides, phenylethanoids, oligosaccharides, quinine, saponins [56], steroids, sesquiterpenoids, tannins [86], ketones, aldehydes, and amides [72,74]. Tese molecules give the plants anticancer, antimicrobial, antioxidant, antidiabetic, anti-infammatory, anthelmintic, antiulcer, antiuretic [82], and cytotoxic activity [35], antibacterial properties [56,58], and the ability to break down various antigens or invasive substances such as NPs [71].…”

“…(pineapple), Passifora edulis Sims (passion fruit) [52], Spinacia oleracea L. (spinach), Musa acuminata Colla (banana) [37], Mentha arvensis L. (mint), Coriandrum sativum L. (coriander), and Cymbopogon citratus (DC.) Stapf (lemongrass) [59]. In the production of household items or ornamental decorations are used Plumeria alba L. [63], Magnolia champaca L. [39], and Terminalia arjuna (Roxb.)…”

“…In study identifcation through databases, it was evident that there are many of these studies. When evaluating them, only the latest studies from the years 2019 (3 studies) [45,47,48], 2020 (4 studies) [35,40,43,44], 2021 (8 studies) [37,39,46,[49][50][51][52][53], and 2022 (11 studies) [41,43,54,56,[58][59][60][61][62][63] were included in this review. Tese statistics show that the biosynthesis of NPs with extracts obtained from diferent parts of the various plants is the most commonly applied method of biological synthesis of NPs.…”

Biosynthesis of Nanoparticles Using Plant Extracts and Essential Oils

“…In this context, the synergistic effect between an antimicrobial plant extract and metallic nanoparticles synthesized in this dispersive medium potentiates the bactericidal and bacteriostatic activities of the technologies and studies developed, extending the synergistic effect with antibiotics, including against multi-antibiotic-resistant bacterial strains [ 252 , 253 ]. In this way, using nanotechnology synthesized from plant extracts presents itself as a potential alternative to the increasing occurrence of nosocomial infections multiresistant to antibiotics and as a key to combating bacterial dissemination through different technological applications made possible in several studies developed over the last few decades.…”