L 3 4 dihydroxyphenylalanin l dopa

The ginseng berries were provided by Gyeonggi Agricultural Research and Extension Services, South Korea. RAW 264.7 and B16 cell lines were provided by the Korean Cell Line Bank (Seoul, South Korea). Arbutin and L-3,4-dihydroxyphenylalanin (L-DOPA) were purchased from Abcam (Cambridge, UK), α-melanocyte-stimulating hormone (α-MSH), Lipopolysaccharide (LPS), and Griess were provided by Sigma (Sigma-Aldrich, St. Louis, MO, USA). Dulbecco Modified Eagle Medium (DMEM), fetal bovine serum (FBS), and antibiotics were supplied by GenDEPOT (Barker, TX, USA); 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) was provided by Life Technologies (Eugene, OR). Antibodies of TNF-α, NF-κB, IκBα were provided by Cell Signal Technology (Danvers, MA, USA), genes primer sequence of TNF-α, IL-1β, IL-6 and iNOS designed by Macrogen (Seoul, South Korea). All other reagent-grade chemicals were purchased from commercial companies.

P. ginseng leaves AuNPs were synthetized and characterized as in our previous report [11] . Dulbecco's modified Eagle's medium (DMEM), fetal bovine serum (FBS) and penicillin–streptomycin solution were purchased from GenDEPOT (Texas, USA), soluble 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) was purchased from Life Technologies (Texas, USA), arbutin and l-3,4-dihydroxyphenylalanin (l-DOPA) were obtained from Abcam (Cambridge, UK), and á-melanocyte stimulating hormone (á-MSH) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were purchased from Sigma (St. Louis, MO, USA).

Gold (III) chloride trihydrate (HAuCl₄·3H₂O), silver nitrate (AgNO₃), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were purchased from Sigma-Aldrich (St Louis, MO, USA). Arbutin and L-3,4-dihydroxyphenylalanin (l-DOPA) were obtained from Abcam (Cambridge, UK). Dulbecco’s Modified Eagle’s Medium (DMEM), high glucose, and pyruvate were purchased from Gibco (Waltham, MA, USA). Fetal bovine serum (FBS) and penicillin–streptomycin solution were purchased from GenDEPOT (Barker, TX, USA). Soluble MTT was purchased from Life technologies (Eugene, OR, USA). The standard neomycin (30 μg/disk) antibiotic disks were obtained from Becton, Dickinson, and Company (Seoul, South Korea). The strains Staphylococcus aureus (ATCC6538) and Escherichia coli (BL-21) were used for antimicrobial studies. The bacterial strains were cultured on nutrient agar media at 37°C and preserved at −70°C in glycerol stock vials for further study.