The present study is designed to investigate the antibacterial effect of the hot-water and various ethanol extracts from the leaves of Dendropanax morbifera L. (DML) against Porphyromonas gingivalis (P. gingivalsis). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of 30, 50 and 70% ethanol extract of DML against P. gingivalis decreased in a concentration-dependent manner. However, MIC and MBC of hot-water and 30% ethanol extract against P. gingivalis were the same as 3.13 and 6.25 mg/mL, respectively. In the bacterial growth inhibition test, the growth of P. gingivalis in the group treated with MBC and 2×MBC of DML hot-water extract was statistically significantly decreased from 6 h after incubation compared to the control group (p<0.001). From the results portrayed above, aqueous extract from DML at the concentration of 6.25 mg/mL can be usefully used to suppress infection of P. gingivalis, a major causative agent of periodontal disease.

The present study is designed to investigate the hypolipidemic effect of the hot-water extract from the leaves of Dendropanax morbifera L. (DMWE) in hyperlipidemic rats. Thirty male 5-week-old rats were grouped as follows: Normal control (NC) given distilled water; hyperlipidemic control (HC) administered with distilled water; drug treatment (DT) orally administered with atorvastatin (10 mg/kg body weight (BW)); DMWE-treated groups (DM-50, DM-100 and DM-200) treated with DMWE 50, 100 and 200 mg/kg BW, respectively. All groups (except for NC) were fed a high-fat diet during the experiment. After 4 weeks of administration, the BW of all groups treated with DMWEs significantly increased compared to that of HC (p<0.05) and showed no significant difference compared to that of NC. In addition, serum total cholesterol levels in all groups treated with DMWEs were meaningfully decreased, compared to that in HC (p<0.05). In serum triglyceride (TG) and low-density lipoprotein-cholesterol levels, both DM-100 and DM-200 considerably decreased compared to HC (p<0.05), and no significant differences in TG levels were between DM-100 and DM-200. In high-density lipoprotein-cholesterol levels, DM-200 was statistically different compared to HC, and there were no significant differences between DM-100, DM-200 and DT. Furthermore, aspartate transaminase and alanine aminotransferase concentrations of DM-100 and DM-200 were significantly decreased compared to those of HC (p<0.05). From results portrayed above, DMWE at the concentration of 100 mg/kg BW has been identified to be effective in the treatment of hyperlipidemic rats.

This study investigated the preventive effect of Dendropanax morbifera leaf extracts (DMLEs) drew out with water, 30, 50 and 70% ethanol against alcohol-induced hepatotoxicity in vitro and vivo. The 3-(4,5-dimethylthiazol-2-yl)-2,5-dipenyltetrazolium bromide (MTT) assay was performed to assess cytotoxic activity of DMLEs, and the half-maximal inhibitory concentration (IC50) ranged between 1.11 and 2.08 mg/mL on Hep3B cells. In preventing ethanol-induced-hepatotoxicity on Hep3B cells, 30 and 50% ethanol DMLEs were significantly effective compared to the 5% ethanol treatment control. In addition, the 30% ethanol DMLE was orally provided to rats 30 min prior to the administration of ethanol (3 mL/kg body weight). At 1, 3 and 5 h after ethanol treatment, the plasma levels of ethanol and acetaldehyde were determined. The 30% ethanol DMLE effectively decreased the plasma ethanol levels during 5 h but increased the plasma acetaldehyde levels until 3 h and then significantly decreased at 5 h, as compared to the control. These results indicate that the 30% ethanol DMLE possesses a potent preventive effect against ethanol-induced liver toxicity in Sprague-Dawley rats.

Background : Extraction is the first and the most important step in the recovery and purification of bio-active compounds from plant materials. Many important factors such as solvent, solvent composition, solvent to solid ratio, pH, and temperature significantly influence the extraction efficiency of bio-active compounds. Factorial design of a limited set of variables is advantageous when compared to the conventional method which varies a single parameter per trial. Methods and Results : The objective of this study was to screen independent factors, namely, ethanol concentration (60 – 100%), extraction temperature (40 – 80℃), time (6 – 18 hours), and liquid to solid ratio (10 – 50 ㎖/g) on the recovery of the extract yield, antioxidant capacity, phenolic and flavonoid contents from Dendropanax morbifera leaf using factorial design. Total flavonoid content of extract was determined by colorimetric method with aluminum chloride, while antioxidant activity was screened using the DPPH radical scavenging activity, TEAC and FRAP assays. Full factorial design was employed to determine the significant contribution of the above factors towards antioxidant capacity (TEAC, DPPH and FRAP), and flavonoid contents. Among, all the factors examined, ethanol concentration and extraction temperature are very significant (p < 0.0001), in obtaining higher antioxidant activity, total flavonoid contents. Conclusion : Two level full factorial design screening was successfully employed to determine the significant factors, which are ethanol concentration, temperature, time and liquid to solid ratio in contributing to high antioxidant capacity (TEAC, DPPH and FRAP), and flavonoid content determination from Dendropanax morbifera leaf. From the results obtained, ethanol concentration and temperature was very significant (p < 0.0001), in obtaining higher antioxidant activity and flavonoid contents. Further work on optimization using these significant factors are in progress.