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A facile synthesis and biological applications of silver (DH-AgNps) and gold nanoparticles (DH-AuNps) mediated by the aqueous extract of Angelicae Pubescentis Radix (Du Huo) are explored. Du Huo is a medicinal root belonging to Angelica pubescens Maxim which possesses anti-inflammatory, analgesic, and antioxidant properties. The absorption spectra of nanoparticles in varying root extract and metal ion concentration, pH, reaction temperatures, and time were recorded by ultraviolet–visible (UV-Vis) spectroscopy. The presence of DH-AgNps and DH-AuNps was confirmed from the surface plasmon resonance intensified at ~414 and ~540 nm, respectively. Field emission transmission electron micrograph (FE-TEM) analysis revealed the formation of quasi-spherical DH-AgNps and spherical icosahedral DH-AuNps. These novel DH-AgNps and DH-AuNps maintained an average crystallite size of 12.48 and 7.44 nm, respectively. The biosynthesized DH-AgNps and DH-AuNps exhibited antioxidant activity against 2,2-diphenyl-1-picrylhydrzyl (DPPH) radicals and the former exhibited antimicrobial activity against clinical pathogens including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica. The expected presence of flavonoids, sesquiterpenes, and phenols on the nanoparticle surface were conjectured to grant protection against aggregation and free radical scavenging activity. DH-AgNps and DH-AuNps were further investigated for their cytotoxic properties in RAW264.7 macrophages for their potential application as drug carriers to sites of inflammation. In conclusion, this green synthesis is favorable for the advancement of plant mediated nano-carriers in drug delivery systems, cancer diagnostic, and medical imaging.Graphical abstractSchematic diagram of biosynthesis of DH-AgNps and DH-AuNps and evaluation of their bioactivities.

Gold (FA-AuNps) and silver (FA-AgNps) nanoparticles were synthesized at room temperature by aqueous extract of dried fruits of Amomum villosum, also known as Fructus Amomi (cardamom), in order to confer antioxidant, catalytic, antimicrobial activities and treatment effect against breast cancer cells. Fruit extracts served as both reducing agents and stabilizers in lieu of chemical agents. Ultra-violet visible (UV-Vis) spectroscopy, field emission transmission electron microscopy (FE-TEM), energy-dispersive X-ray (EDX) spectroscopy, elemental mapping, X-ray powder diffraction (XRD), selected area electron diffraction (SAED), dynamic light scattering (DLS) and Fourier transform infrared (FTIR) spectroscopy were employed to characterize the biosynthesized nanoparticles. Both FA-AuNps and FA-AgNps exhibited free radical scavenging activity against 2,2-diphenyl-1-picrylhydrzyl (DPPH). Additionally, biosynthesized nanoparticles successfully reduced methylene blue, a well-known redox indicator. FA-AgNps showed zones of inhibition against pathogenic Staphylococcus aureus and Escherichia coli. Finally, the biological activities and cytotoxicity of nanoparticles were subsequently investigated in vitro. FA-AuNps demonstrated a potential cytotoxic agent against breast cancer cells as evaluated by MTT assay. The study highlights a rapid synthesis of FA-AuNps and FA-AgNps by dried Fructus Amomi aqueous extract and evaluates their potential biological applications on medical platforms.

There has been a growing interest in the design of environmentally affable and biocompatible nanoparticles among scientists to find novel and safe biomaterials. Panax ginseng Meyer berries have unique phytochemical profile and exhibit beneficial pharmacological activities such as antihyperglycemic, antiobesity, antiaging, and antioxidant properties. A comprehensive study of the biologically active compounds in ginseng berry extract (GBE) and the ability of ginseng berry (GB) as novel material for the biosynthesis of gold nanoparticles (GBAuNPs) and silver nanoparticles (GBAgNPs) was conducted. In addition, the effects of GBAuNPs and GBAgNPs on skin cell lines for further potential biological applications are highlighted. GBAuNPs and GBAgNPs were synthesized using aqueous GBE as a reducing and capping agent. The synthesized nanoparticles were characterized for their size, morphology, and crystallinity. The nanoparticles were evaluated for antioxidant, anti-tyrosinase, antibacterial, and cytotoxicity activities and for morphological changes in human dermal fibroblast and murine melanoma skin cell lines. The phytochemicals contained in GBE effectively reduced and capped gold and silver ions to form GBAuNPs and GBAgNPs. The optimal synthesis conditions (ie, temperature and v/v % of GBE) and kinetics were investigated. Polysaccharides and phenolic compounds present in GBE were suggested to be responsible for stabilization and functionalization of nanoparticles. GBAuNPs and GBAgNPs showed increased scavenging activity against 2,2-diphenyl-1-picrylhydrazyl free radicals compared to GBE. GBAuNPs and GBAgNPs effectively inhibited mushroom tyrosinase, while GBAgNPs showed antibacterial activity against Escherichia coli and Staphylococcus aureus . In addition, GBAuNPs were nontoxic to human dermal fibroblast and murine melanoma cell lines, and GBAgNPs showed cytotoxic effect on murine melanoma cell lines. The current results evidently suggest that GBAgNPs can act as potential agents for antioxidant, anti-tyrosinase, and antibacterial activities. In addition, GBAuNPs can be further developed into mediators in drug delivery and as antioxidant, anti-tyrosinase, and protective skin agents in cosmetic products. Consequently, the study showed the advantages of using nanotechnology and green chemistry to enhance the natural properties of GBs.

BackgroundGinsenoside F1 has been described to possess skin-whitening effects on humans. We aimed to synthesize a new ginsenoside derivative from F1 and investigate its cytotoxicity and melanogenesis inhibitory activity in B16BL6 cells using recombinant glycosyltransferase enzyme. Glycosylation has the advantage of synthesizing rare chemical compounds from common compounds with great ease.MethodsUDP-glycosyltransferase (BSGT1) gene from Bacillus subtilis was selected for cloning. The recombinant glycosyltransferase enzyme was purified, characterized, and utilized to enzymatically transform F1 into its derivative. The new product was characterized by NMR techniques and evaluated by MTT, melanin count, and tyrosinase inhibition assay.ResultsThe new derivative was identified as (20S)-3β,6α,12β,20-tetrahydroxydammar-24-ene-20-O-β-D-glucopyranosyl-3-O-β-D-glucopyranoside (ginsenoside Ia), which possesses an additional glucose linked into the C-3 position of substrate F1. Ia had been previously reported; however, no in vitro biological activity was further examined. This study focused on the mass production of arduous ginsenoside Ia from accessible F1 and its inhibitory effect of melanogenesis in B16BL6 cells. Ia showed greater inhibition of melanin and tyrosinase at 100 μmol/L than F1 and arbutin. These results suggested that Ia decreased cellular melanin synthesis in B16BL6 cells through downregulation of tyrosinase activity.ConclusionTo our knowledge, this is the first study to report on the mass production of rare ginsenoside Ia from F1 using recombinant UDP-glycosyltransferase isolated from B. subtillis and its superior melanogenesis inhibitory activity in B16BL6 cells as compared to its precursor. In brief, ginsenoside Ia can be applied for further study in cosmetics.

The current study highlights the rapid biosynthesis of gold nanoparticles (Gu-AuNps) and silver chloride nanoparticles (Gu-AgClNps) by aqueous root extract of Glycyrrhiza uralensis, a medicinal plant. G. uralensis has been reported for anticancer and hepatoprotective effects. The reduction of chloroauric acid and silver nitrate by the Glycyrrhiza root extract prompted the formation of Gu-AuNps and Gu-AgClNps within 4 and 40 min at 80 °C, respectively. The complete reaction did not require supplemental reducing and stabilizing agents, which demonstrated green synthesis. Field emission transmission electron microscopy (FE-TEM) revealed the spherical shape of Gu-AuNps and Gu-AgClNps. X-ray diffraction (XRD) showed face-centred cubic structure of Gu-AuNps and Gu-AgClNps with average crystallite size 12.25 nm and 8.01 nm, respectively. The biosynthesized Gu-AgClNps served as competent antimicrobial agent against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella enterica. Additionally, Gu-AuNps and Gu-AgClNps were analyzed for their catalytic ability to reduce methylene blue as model test pollutant. Likewise, both nanoparticles possessed free radical scavenging activity against 2,2-diphenyl-1-picrylhydrzyl (DPPH). Moreover, in vitro cytotoxicity in murine macrophage (RAW264.7) and human breast cancer (MCF7) cells were evaluated. Thus, the study proposes a green synthesis of Gu-AuNps and Gu-AgClNps by G. uralensis extract and in vitro biological applications. [Formula: see text].

Green synthesis of gold (CB-AuNps) and silver (CB-AgNps) nanoparticles using Cibotium barometz root extract was highlighted. CB-AuNps were synthesized almost instantly and CB-AgNps were formed after 25 min in a heated aqueous extract. The formation of CB-AuNps and CB-AgNps was detected at 548 and 412 nm; they were spherical with crystallite sizes of 6 nm and 23 nm, respectively. CB-AgNps were further investigated for their antimicrobial activity against Escherichia, Staphylococcus aureus, Salmonella enterica, and Pseudomonas aeruginosa. Furthermore, scavenging activity against 1,1-diphenyl-2-picrylhydrzyl (DPPH) free radicals was demonstrated. Lastly, the cytotoxic properties of CB-AuNps and CB-AgNps were explored in murine macrophages (RAW264.7) cells and MCF-7 breast cancer cells. This study demonstrated the prospective biomedical applications of CB-AuNps and CB-AgNps as antioxidant, antimicrobial agents, and drug-delivery agents.

The design of mild and non-toxic synthesis of metallic nanoparticles is a topical subject in the nanotechnology field. The objective of this present study is to screen the bioactivity of biosynthesized nanoparticles by aqueous fruit extract of Chaenomeles sinensis. The reducing and stabilizing ability of C. sinensis to fabricate gold (Cs-AuNps) and silver (Cs-AgNps) nanoparticles was confirmed by UV-visible (UV-Vis) spectroscopy at 562 nm and 477 nm, respectively. The field-emission transmission electron microscopy (FE-TEM) and X-ray diffraction analysis (XRD) verify the nano-scale morphology and crystallinity of Cs-AuNps (20-40 nm) and Cs-AgNps (5-20 nm). Furthermore, we evaluated the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, antimicrobial activity against Staphylococcus aureus and Escherichia coli and cytotoxicity against breast cancer cells. The results showed that Cs-AuNps (IC: 725.93 μg/mL) displayed superior inhibitory activities on DPPH than Cs-AuNps. The biosynthesized Cs-AuNps successfully inhibited the growth of pathogenic bacteria S. aureus (ATCC 6538) and E. coli (BL21). The cytotoxic effect of Cs-AuNps and Cs-AgNps was evaluated in murine macrophage (RAW264.7) and human breast cancer cell lines (MCF7) by MTT assay. Thus, the present study explores the biomedical applications of gold and silver nanoparticles synthesized by C. sinensis.