본 연구에서 SCLE와 그 분획의 총 폴리페놀과 플라보노이드의 함량을 측정한 결과 SCLE/EA에서 가장 많은 함량이 확인되었으며, DPPH 및 ABTS radical scavenging activity, SOD-like activity, reducing power 측정을 통한 항산화 활성을 비교한 결과도 폴리페놀과 플라보노이드함량 측정 결과와 마찬가지로 SCLE/EA에서 높은 활성을 명확하게 확인할 수 있었다. 그리고 SCLE 및 분획의 항당뇨 효능을 ${alpha}$-glucosidase 활성억제능을 측정함으로써 비교한 결과 항산화력과 달리 SCLE/BuOH에서 가장 높은 활성을 확인할 수 있었으며, 1 mg/mL 기준으로 acarbose의 ${alpha}$-glucosidase 활성억제능과 비교하여 2배 이상의 활성을 관찰할 수 있었다. 또한 당뇨와 비만의 강한 관련성이 알려진 상황에서 SCLE 및 그 분획의 3T3-L1 세포 분화 억제능력을 확인한 결과 SCLE와 SCLE/FW에서 가장 강한 억제효과를 확인할 수 있었다. 본 연구를 통해 SCLE가 다방면에서 당뇨의 개선과 예방을 위해 효능을 나타낼 수 있음을 확인하였고, 이는 SCLE가 neutraceuticals 소재로서의 개발가치가 높음을 시사한다.
Smilax china L., a native plant found in Asian countries, has several medicinal properties including antioxidant, anti-inflammatory, and anti-cancer effects. Although the root of the plant is commonly used as traditional herbal medicine in Korea and China, the medicinal properties of the leaves have not gained the same attention. In this study, we analyzed the antioxidant activity, ${alpha}$-glucosidase inhibitory effect and lipid accumulation inhibition effect of Smilax china L. leaf water extract (SCLE) and its solvent fractions. SCLE was fractionated by using a series of organic solvents, including ethylacetate (EA) and n-butanol (BuOH). The EA fraction had the highest total polyphenol content ($440.20{pm}12.67$ mg GAE/g) and total flavonoid content ($215.14{pm}24.83$ mg QE/g). The radical scavenging activity $IC_{50}$ values of the EA fraction for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) were 0.022 mg/mL and 0.13 mg/mL, respectively. Further, SOD-like activity and reducing power values of the EA fraction were higher than those of the other fractions. However, both the ${alpha}$-glucosidase and lipid accumulation inhibition assays showed that the BuOH fraction ($83.35{pm}4.18%$ at 1 mg/mL) and water extract ($11.27{pm}2.67%$) were more effective than the EA fraction ($64.13{pm}6.35%$, and $45.66{pm}7.20%$). These results provide new insights into the potential anti-diabetic and anti-obesity effects of Smilax china L. leaf.
