Today, the green synthesis of metal nanoparticles is a promising strategy in material science and nanotechnology. In this research, silver nanoparticles (AgNPs) were synthesized through the high-efficient, cost-effective green and facile process, using the Astragalus tribuloides Delile. root extract as a bioreduction and capping agent at room temperature. UV–Vis spectroscopy was applied for the investigation of the reaction proceedings. To characterize the greenly synthesized AgNPs, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), and transmission electron microscopy (TEM) analyses were utilized. In addition, the total phenolics and flavonoids contents, antioxidant, antibacterial, and anti-inflammatory activities of the greenly synthesized AgNPs and the A. tribuloides root extract were evaluated. The results indicated that the AgNPs had spherical morphology and crystalline structure with the average size of 34.2 ± 8.0 nm. The total phenolics and flavonoids contents of the greenly synthesized AgNPs were lower than those for the A. tribuloides root extract. The resultant AgNPs exhibited the appropriate antioxidant activity (64%) as compared to that for the A. tribuloides root extract (47%). The antibacterial test approved the higher bactericidal activity of the resulting AgNPs on the Gram-positive and Gram-negative bacteria in comparison to the A. tribuloides root extract. Considering the anti-inflammatory activity, the greenly synthesized AgNPs showed a stranger effect than the A. tribuloides root extract (82% versus 69% at 500 μg/mL). Generally, the AgNPs that were fabricated by using the A. tribuloides root extract had appropriate antioxidant, antibacterial, and anti-inflammatory activities and, therefore, can be considered as a promising candidate for various biomedical applications.

In this study, very simple and fast one-step synthesis of biogenic silver chloride nanoparticles (AgCl-NPs) using a Pulicaria vulgaris Gaertn. aerial part extract from an aqueous solution of silver nitrate at room temperature is proposed. The proceedings of the reaction were investigated by UV–Vis spectroscopy. AgCl-NPs were characterized using X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Antibacterial and antifungal activities of these nanoparticles were evaluated by disk diffusion and microdilution methods against Staphylococcus aureus, Escherichia coli, Candida albicans, and C. glabrata. In addition, the antioxidant activity of the synthesized AgCl-NPs was determined by the DPPH radical scavenging assay. The antimicrobial test confirmed the bactericidal activity of biosynthesized AgCl-NPs against Gram-positive and Gram-negative bacteria. They also exhibited good antifungal activities with minimum inhibitory concentration (MIC) values ranging from 40 to 60 µg/mL against Candida glabrata and Candida albicans, respectively. In addition, biosynthesized AgCl-NPs were established to have remarkable antioxidant activity. All this pointed out that the proposed new biosynthesis approach resulted in production of AgCl-NPs with convenient biomedical applications.

In the last years, the plant-mediated synthesis of nanoparticles has been extensively researched as an affordable and eco-friendly method. The current study confirms for the first time the capability of the Otostegia persica (Burm.) Boiss. leaf extract for the synthesis of silver nanoparticles (AgNPs). The phytofabricated AgNPs were characterized by ultraviolet–visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and zeta potential analysis. Moreover, the total phenolic and flavonoids contents, and the antioxidant, antibacterial, antifungal, and anti-inflammatory properties of the phytofabricated AgNPs and the O. persica leaf extract were assessed. The results showed that the produced AgNPs were crystalline in nature and spherical in shape with an average size of 36.5 ± 2.0 nm, and indicated a localized surface plasmon resonance (LSPR) peak at around 420 nm. The zeta potential value of −25.2 mV pointed that the AgNPs were stable. The phytofabricated AgNPs had lower total phenolic and flavonoids contents than those for the O. persica leaf extract. The abovementioned AgNPs showed a higher antioxidant activity as compared with the O. persica leaf extract. They also exhibited significant antibacterial activity against both Gram-positive (Staphylococcus aureus, Bacillus subtilis, and Streptococcus pyogenes) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi) bacteria. In addition, appropriate antifungal effects with the minimum inhibitory concentration (MIC) values of 18.75, 37.5, and 75 µg mL⁻¹ against Candida krusei, Candida glabrata, and Candida albicans, respectively, were noted for this new bionanomaterial. Finally, the phytofabricated AgNPs showed dose-dependent anti-inflammatory activity in the human red blood cell (RBC) membrane stabilization test, being higher than that for the O. persica leaf extract. The resulting phytofabricated AgNPs could be used as a promising antioxidant, antibacterial, antifungal, and anti-inflammatory agent in the treatments of many medical complications.

The aim of the present study was to investigate the changes in the content of phytochemical compounds and in vitro antioxidant, antibacterial, and anti-inflammatory activities of Teucrium polium L. aerial parts and root methanolic extracts at different phenological stages (vegetative, flowering, and seeding). The T. polium extracts were analyzed using gas chromatography–mass spectrometry (GC-MS), and their antioxidant properties were tested with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), ferrous ions (Fe²⁺), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. Forty-nine compounds were identified with the majority of germacrene D, t-cadinol, β-pinene, carvacrol, bicyclogermacrene, α-pinene, and limonene. The results show that the extracts significantly differ between different phenological stages of the plant material used in terms of the phytochemical composition (total phenolic compounds, total flavonoids, total alkaloids, and total saponin contents) and bioactivities (antioxidant, antibacterial, and anti-inflammatory) (p < 0.05). The highest total contents of phenolics (72.4 ± 2.5 mg gallic acid equivalent (GAE)/g dry weight), flavonoids (36.2 ± 3.1 mg quercetin equivalent (QE)/g dry weight), alkaloids (105.7 ± 2.8 mg atropine equivalent (AE)/g dry weight), and saponins (653 ± 6.2 mg escin equivalent (EE)/g dry weight), as well as antioxidant, antibacterial, and anti-inflammatory activities, were measured for the extract of the aerial parts obtained at the flowering stage. The minimum inhibitory concentration (MIC) values for the extracts were varied within 9.4–300 µg/mL, while the minimum bactericidal concentration (MBC) values were varied within 18.75–600 µg/mL. In addition, they were more active on Gram-positive bacteria than Gram-negative bacteria. The data of this work confirm that the T. polium extracts have significant biological activity and hence can be used in the pharmaceutical industry, clinical applications, and medical research, as well as cosmetic and food industries.