Four novel compounds-two phenylpropionamides, one piperidine, and one phenolic derivatives-were isolated and identified from the fruit of a medicinal plant, Ailanthus altissima (Mill.) Swingle (Simaroubaceae), together with one known phenylpropionamide, 13 known phenols, and 10 flavonoids. The structures of the new compounds were elucidated as 2-hydroxy-N-[(2-O-β-d-glucopyranosyl)phenyl]propion...

Bioassay-guided investigation of the branches of Cleyera japonica led to the isolation of four phenolic constituents: 3,3’-di-O-methylellagic acid (1), 3,3’-di-O-methylellagic acid 4’-O-β-D-xylofuranoside (2), 3,5,7-trihydroxychromone 3-O-α-L-arabinofuranoside (3) and aviculin (4). Their structures were elucidated on the basis of spectral studies, as well as by comparison with literature data. ...

In order to develop a new skin whitening agent, safflower (Carthamus tinctorius L.) seeds were evaluated for melanogenesis inhibitory activity and its active principles were identified following activity-guided isolation. The 80% aqueous methanol extract and ethyl acetate fraction from safflower seeds showed a significant inhibition for mushroom tyrosinase. Three active compounds, N-feruloylser...

The inhibition of tyrosinase is the most effective method to decrease melanin synthesis during the process of pigmentation. We aimed to find compounds from traditional Chinese medicines (TCM) that are more effective than the most commonly used tyrosinase inhibitor, arbutin. First, we employed homology modeling to construct a tyrosinase-modeled structure, and structure-based virtual screening to...

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With regard to the importance of antioxidants in foods, cosmetics and pharmaceutics, there are several studies on natural resources for finding rich sources of antioxidants and their role in protecting the body against oxidative stress injuries. The purpose of this study was to investigate the antioxidant stability of arbutin and the Pyrus boissieriana buhse Leaf extract and their effects on li...

BACKGROUND Hyperpigmentary disorders like melasma, actinic and senile lentigines are a major cosmetic concern. Therefore, many topical products are available, containing various active ingredients aiming to reduce melanin production and distribution. The most prominent target for inhibitors of hyperpigmentation is tyrosinase, the key regulator of melanin production. Many inhibitors of tyrosinas...

The fermentation of lactose by salmonellae has seldom been accomplished, and in but few serological types (Kauffmann, 1954; Kristensen, 1948, 1955). In previous investigations we (Schafler and SchiLfler, 1959) succeeded in obtaining lactose-positive variants in 17 out of 30 salmonella strains belonging to different types, by means of 32 to 150 days of incubation on partially defined media conta...