상백피의 기능성식품 소재로서의 이용 가능성을 조사하기 위하여 상백피 물 추출물의 항산화 활성 및 in vitro에서의 항천식 효과를 확인하였다. 항산화 측정 결과는 총 페놀함량은 35.2 mg/g로 나타났으며, DPPH radical 소거능은 35.3~59.8%, hydroxyl radical 소거능은 62.1~78.8% 범위로 높은 항산화 효능을 나타내었다. DNP-IgE와 HSA로 활성화된 RBL-2H3 세포에서의 항천식 효과는 농도가 증가할수록 유의적으로 $eta$-hexosaminidase를 감소시켰으며, 염증성 cytokine인 IL-4, TNF-$alpha$ 사이토카인 분비량 또한 유의적(p<0.05)으로 감소시켰다. 결과적으로 상백피는 높은 항산화력을 가지며, 항천식과 관련된 지표들을 유의적으로 감소시킴으로써 천식 예방 및 개선을 위한 기능성 소재로서 이용가치가 높을 것으로 사료된다.
This study was performed to evaluate the antioxidant activities and anti-asthma effects of Morus bark water extracts. Inhibitory effect of Morus bark onto free radical generation was determined by measuring DPPH and hydroxyl radical scavenging activities in vitro. Anti-asthma activities of Morus bark water extracts were assessed by testing their effects on the degranulation of mast cell. For this, $eta$-hexosaminidase released from a basophilic cell line, RBL-2H3 was used and pro-inflammatory cytokines were measured by ELISA kit. The antioxidant activities of water extracts of Morus bark was 59.2% in the DPPH assay at $2,000;{mu}g/mL$ and 78.8% in the hydroxyl radical scavenging assay at $2,000;{mu}g/mL$. Our results indicated that Morus bark water extracts effectively inhibited free radical generation. Morus bark water extracts inhibited inflammation-mediating substances such as histamine and $eta$-hexosaminidase release from RBL-2H3 cells. Cytokine release demonstrated a more effective blockading ability of the Morus bark water extracts to the release of IL-4 and TNF-$alpha$ compared to control. These results demonstrate that Morus bark may be beneficial in the treatment of allergic inflammatory disease.
