Physiological Activities of Rubus coreanus Miq. Extracts Using Different Extraction Methods

추출방법에 따른 복분자 추출물의 생리활성

This study was carried out to evaluate biological activities concerning extracts according to extraction methods from unripened fruit of Rubus coreanus Miq. The extraction methods were HWE (hot water extraction for 4 hr at $100^{\circ}C$), SFE (extraction for 3 hr at $40^{\circ}C$ under 300 bar, 100% of $CO_2$ fluid), USE (ultrasonification extraction for 4 hr at $50^{\circ}C$ with water), USE+HWE (hot water extraction for 2 hr at $100^{\circ}C$ after ultrasonification process for 2 hr), VE (vacuum extraction for 4 hr at $90^{\circ}C$ under 0.9 bar with water). VE extract showed the highest contents of total polyphenol ($178.78{\pm}3.79\;mg/g$) and total flavonoid ($40.93{\pm}0.68\;mg/g$). $IC_{50}$ values of DPPH radical scavenging activity, linoleic acid peroxidation inhibition activity and LDL (low density lipoprotein) oxidation inhibition activity of HWE extract showed the lowest $35.39{\pm}0.25{\mu}g/mL$, $12.61{\pm}0.31{\mu}g/mL$ and $1.31{\pm}0.02{\mu}g/mL$ among other all extracts, respectively. $IC_{50}$ values of ${\alpha}$-glucosidase inhibitory activities of VE and HWE extracts showed lower $14.34{\pm}0.20{\mu}g/mL$ and $15.83{\pm}0.20{\mu}g/mL$ than those of other extracts, respectively. Specifically, HWE and VE extracts have relatively better biological activities than other extracts; these could be potentially used as a bioactive source for health functional foods.