Arginine-fructose-glucose from red ginseng extract reduces stiffness of keratin fiber in corneocyte of skin.

PURPOSE: The moisture content of the stratum corneum of the skin changes depending on the external environment. The structure of keratinous fiber protein in corneocyte of the skin changes depending on the amount of moisture. As the moisture decreases, the population of the alpha-helix increases, the beta-sheet deceases, and the stiffness increases accordingly. Here, we investigated the effect of humectants from ginseng on the keratin structure. METHODS: Corneocyte was prepared from dry porcine skin with disc tape and measured through ATR-FT-IR. The signal from amide I of the keratin protein in corneocyte was detected, and the change in the ratio of alpha-helix and beta-sheet was calculated. The test samples were treated on the exfoliated corneocyte, and the degree of change was checked. RESULT: Arginine-fructose-glucose (AFG)-enriched extract of red ginseng was effective in changing the keratin structure and was superior to humectants such as glycerin. However, arginine, mono sugar were not effective, and the AFG form in which two sugars were bound to one amino acid could perform its function. CONCLUSION: The present study suggests that AFG, when applied to cosmetics, is expected to improve skin texture in a different way from existing moisturizers represented by glycerin by reducing the alpha-helix structure of corneocyte keratin.

New insights into the ageing of linseed oil paint binder: a qualitative and quantitative analytical study.

This paper presents an analytical investigation of paint reconstructions prepared with linseed oil that have undergone typical 19th century treatments in preparation for painting. The oil was mechanically extracted from the same seed lot, which was then processed by various methods: water washing, heat treatments, and the addition of driers, with and without heat. A modern process lead white (Dutch source, Schoonhoven) and a commercially available vine black were used as pigments. The reconstructions were prepared in 1999, and naturally aged from then onwards. We compared thermogravimetric analysis (TG), which yields macromolecular information, with gas chromatography-mass spectrometry (GC-MS) and direct exposure mass spectrometry (DEMS), which both provide molecular information. The study enabled us to quantitatively demonstrate, for the first time, that the parameters used to identify drying oils are deeply influenced by the history of the paint. In particular, here we show that the ratio between the relative amounts of palmitic and stearic acid (P/S), which is used as an index for differentiating between drying oils, is extremely dependent on the pigments present and the age of the paint. Moreover the study revealed that neither the P/S parameter nor the ratios between the relative amounts of the various dicarboxylic acids (azelaic over suberic and azelaic over sebacic) can be used to trace the sorts of pre-treatment undergone by the oil investigated in this study. The final results represent an important milestone for the scientific community working in the field, highlighting that further research is still necessary to solve the identification of drying oils in works of art.