RESUMO
In recent years, collagen peptides (CP) have become a research hotspot in delaying chronological skin aging. Animal experiments have shown that CP can repair chronologically aged animal skin by promoting collagen synthesis, inhibiting collagen degradation, and increasing antioxidant enzyme activity. Cell experiments showed that CP can promote proliferation of fibroblasts and synthesis of collagen and elastin by stimulating nuclear factor-κB signaling pathway and transforming growth factor-β/drosophila mothers against decapentaplegic signaling pathway. Clinical studies have demonstrated that long-term oral supplement with CP or CP in combination with other antioxidant active substances can increase the skin moisture content and reduce transepidermal water loss, improve skin wrinkles and elasticity, as well as improve the skin collagen fiber structure, dermal and epidermal quality and the overall condition of facial skin. This review summarizes recent studies on mechanisms underlying chronological skin aging and mechanisms of action of CP in repairing chronologically aged skin, in order to provide a theoretical basis for further clinical research into and application of CP in repairing chronologically aged skin.
RESUMO
OBJECTIVE： To establish a method for content determination of total polyphenols from Gastrodia elata， and to optimize the purification technology of macroporous resin. METHODS： The content of total polyphenols from G. elata was determined by Folin-ciocaileu colorimetry. Using the absorption and desorption performance as index， 4 kinds of macroporous adsorption resins were selected by static adsorption and desorption tests. The flow rate and mass concentration of the sampling solution， volume fraction of eluent， eluent flow rate and eluent volume were investigated by dynamic adsorption and desorption tests. The purification technology of macroporous resin was optimized. RESULTS： The linear range of gallic acid was 4-32 μg/mL （r＝0.999 9）. RSDs of precision， stability and repeatability tests were all less than 2％. The recovery rate of the sample was 95.51％-102.94％（RSD＝2.54％，n＝6）. D301 macroporous resin had strong static adsorption and desorption ability from G. elata polyphenols. The optimal purification technology included that the sample solution flow rate 2 BV/h； the sample solution mass concentration 4 mg/mL； the elution solvent 70％ ethanol； the elution flow rate was 3 BV/h， and the eluent volume 5 BV. The content of total polyphenols from G. elata optimized by the optimal purification technology was 0.381 mg/g. CONCLUSIONS： Established method is sensitive and stable. The optimized purification technology is stable and feasible.