Screening And Activity Study Of Soothing Substances From Plants

Due to the influence of environmental pollution,social pressure and self-factors,the incidence of sensitive skin is increasing day by day,and the demand for functional skin care products with soothing skin sensitivity has greatly increased,coupled with pursuit of green and safe cosmetics,the research of natural soothing active substances has become a hot direction.The occurrence of sensitive skin involves many aspects,among which the impairment of skin barrier function is the main cause of sensitive skin,so maintaining and repairing skin barrier function is the main way to relieve skin sensitivity.At present,the test methods related to the evaluation of soothing efficacy mainly include anti-hemolysis test,anti-oxidant test,anti-allergic test and anti-inflammatory test,and so on.In this paper,under the guidance of soothing activity,the plant raw materials that may have better soothing activity were screened,and then the selected raw materials were extracted,separated and purified,and the main active components were analyzed and identified.The soothing effect of active fractions was evaluated from multiple dimensions,so as to provide a scientific basis for the development of plant-derived soothing active substances.The main results are as follows:（1）On the basis of literature research,22 kinds of plant raw materials with soothing potential were selected and extracted with aqueous.The soothing activity of 22 kinds of extracts was detected by hemolysis test,anti-hemolysis test and hyaluronidase inhibition test.The results showed that Cornus officinalis had the best soothing activity.When the crude drug concentration was 200 mg/m L,the hemolysis rate was-1.6±0.3%,and the hemolysis inhibition rate was 81.2±1.0%.When the crude drug concentration was 400 mg/m L,the hyaluronidase inhibition rate was 99.6±7.4%.（2）The soothing active fractions of Cornus officinalis were screened by using hyaluronidase inhibitory activity as an index.First,the crude extract of Cornus officinalis was extracted with 75%ethanol solution,and then 4 different polar parts were obtained by gradient extraction.The results of hyaluronidase inhibition experiment showed that the soothing activity of petroleum ether part of Cornus officinalis was the highest,and the IC₅₀ value was 3.11mg/m L.The petroleum ether part of Cornus officinalis was separated and purified by rapid preparation chromatography,and 18 fractions were obtained,which were named COPE-1-18in turn.The soothing activity of each fraction was detected by hyaluronidase inhibition method.The results showed that the activity of fractions COPE-7,COPE-8,COPE-9 and COPE-10 was outstanding,and the IC₅₀ values were 1.12,1.07,0.87,1.04 mg/m L,respectively.The components of COPE-7,COPE-8,COPE-9 and COPE-10 were analyzed by GC-MS.The results showed that the terpenoids were the mainly soothing active substances in Cornus officinalis,including Lupeol,α-Amyrin,β-Amyrin,δ-14-Serratene and Urs-12-en-28-al.（3）The soothing effect of active fractions of Cornus officinalis was evaluated by cell degranulation inhibition test,anti-inflammatory test and antioxidant test.The toxicity of fractions COPE-7,COPE-8,COPE-9 and COPE-10 to RBL-2H3 cells,RAW264.7 cells and Ha Ca T cells was detected by MTT method.The results showed that fraction COPE-7 had no effect on the viability of 3 kinds of cells in the concentration range of 0-40μg/m L.Fraction COPE-8 had no effect on the viability of RBL-2H3 cells and RAW264.7 cells in the concentration range of 0-20μg/m L,and had no effect on the viability of Ha Ca T cells in the concentration range of 0-40μg/m L.Fraction COPE-9 and fraction COPE-10 had no effect on the viability of 3 kinds of cells in the concentration range of 0-1.25μg/m L.The effects of fractions COPE-7,COPE-8,COPE-9 and COPE-10 on the degranulation model of RBL-2H3cells induced by calcium ionophore A23187 were detected by RBL-2H3 cell degranulation inhibition test.The results showed that fraction COPE-8 had the best inhibitory effect on RBL-2H3 cell degranulation,reducing the histamine release rate to 54.3±0.9%（inhibition rate was76.2±1.1%）and reducing theβ-hexosaminidase to 60.8±3.3%（inhibition rate was 43.9±4.9%）at 20μg/m L.ELISA kit was used to detect the effects of fractions COPE-7,COPE-8,COPE-9 and COPE-10 in the inflammatory model of RAW264.7 cells induced by LPS.The results showed that fraction COPE-7 had the best inhibitory effect on cytokine secretion,reducing the expression of cytokine TNF-αto 526.9 pg/m L at 40μg/m L,with an inhibition rate of 71.3±4.6%.The expression of cytokine IL-6 was reduced to 304.9 pg/m L at the concentration of 10μg/m L,and the inhibition rate was 80.5±0.5%.The antioxidant activities of fractions COPE-7,COPE-8,COPE-9 and COPE-10 were detected by DPPH,ABTS,FRAP and ORAC methods.The results showed that the soothing activities of factions COPE-7 and COPE-10 were outstanding,and their DPPH radical scavenging rates at 1 mg/m L were 32.9±1.0%and 19.5±1.2%,respectively.The ABTS radical scavenging rates at 1 mg/m L were 20.6±2.2%and 12.2±1.1%,respectively.The FRAP values at 1 mg/m L were 40.6±12.8 and 315.9±21.9,respectively.The ORAC values at 0.1 mg/m L were 331.6±30.5μmol TE/g and 323.9±40.6μmol TE/g,respectively.CAA method.The results showed that the antioxidant activities of fractions COPE-7 and COPE-8 were better,and the CAA values at 40μg/m L were 93.9±2.1 and 78.6±0.9,respectively.