Antimicrobial, Antioxidant and Cellular Protective Effects of Houttuynia cordata Extract and Fraction

This study was conducted to investigate the physiological activities of Houttuynia cordata extracts and fractions. H. cordata extracts were extracted with 50% ethanol and the ethyl acetate fractions were obtained from the extracts. Minimum inhibitory concentration (MIC) values of the ethyl acetate fraction for S. aureus and B. subtilis were 78 mu g/mL and 312 mu g/mL, respectively, indicating the high activity against gram-positive bacteria. The free radical scavenging activity (FSC50) for 1,1-diphenyl-2-picrylhydrazyl (DPPH) was higher in the ethyl acetate fraction with 12.00 mu g/mL compared to that of 27.15 mu g/mL for 50% ethanol extract. The total antioxidant activity (OSC50) values for reactive oxygen species (ROS) produced in Fe3+-EDTA/H2O2 system by a luminol-dependent chemiluminescence method were 2.91 and 0.983 mu g/ml for the 50% ethanol extract and ethyl acetate fraction, respectively. To investigate cellular protective effects on the HaCaT cell, the intracellular ROS scavenging activity was measured after UVB irradiation and the ethyl acetate fraction of H. cordata showed the activity in a concentration-dependent from 1.6 mu g/mL and a reduction rate of 54.3% at a maximum concentration of 12.5 mu g/mL. Also, HaCaT cell protective effect against H2O2 -mediated decreased the cell viability of the ethyl acetate fraction of H. cordata which significantly increased the cell viability from 0.8 mu g/mL and the maximum cell viability showed 86.9%. The ethyl acetate fraction of the H. cordata extracts was analyzed by TLC and HPLC. As a result, quercitrin, isoquercitrin, hyperoside, chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, rutin and afzelin were identified. From the above results, it was suggested that the extracts and fractions of H. cordata have a potential to be applied in the field of cosmetics as a natural antioxidant/preservative capable of protecting the cell membrane from the oxidative stress by eliminating ROS and exhibiting the antimicrobial effect.