In a continuing screening of selected medicinal plants native to Mongolia, the antioxidant and α-glucosidase inhibitory activities of methanol extract of Iris bungei were investigated. After extraction with 80% of methanol, the methanol fraction was further extracted with n-hexane, EtOAc and n-BuOH in order to obtain four different solvent-soluble fractions, namely n-hexane-soluble, EtOAc-soluble, n-BuOH-soluble and H2O residue. The antioxidant properties were evaluated by radical scavenging assay using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS+) radicals. The anti-diabetic efficacy of I. bungei extract was investigated by α-glucosidase assay. All tested samples showed dose-dependent radical scavenging and α-glucosidase inhibitory activities. Among the tested extracts, the EtOAc-soluble fractions showed the greatest radical scavenging activity and α-glucosidase inhibitory properties among other solvent-soluble fractions. This result suggested that there was a significant relationship between the total phenolic content and biological efficacy. Thus, I. bungei extract might be considered as a new potential source of natural antioxidant and as a α-glucosidase inhibitory source. A more systematic investigation of this biomass sill be performed for further investigation of activity against antioxidative and anti-diabetic effects.

Phloridzin is a predominant member of the chemical class of dihydrochalcones and mainly found in apple. The biological activity of phloridzin treated with dielectric barrier discharge (DBD) plasma was evaluated to investigate whether exposure to plasma can be used as a tools to enhance the biological activity of natural resources. DBD plasma treatment of phloridzin was carried out for three different exposure times. The antioxidant effects of degraded phloridzin for different reaction time were evaluated via radical scavenging assay using DPPH radical. In addition, the anti-diabetic and anti-obesity properties of the degraded phloridzin were measured based on α-glucosidase and pancreatic lipase inhibitory activities. Phloridzin treated for 60 min showed significantly higher radical scavenging, α-glucosidase and pancreatic lipase inhibitory activities compared to the tested positive controls. Degradation of phloridizin induced by DBD plasma might be responsible for enhancing the biological activity of phloridizin.

신선한 곤드레를 메탄올로 침지 추출하여 얻어진 추출물 에 대해 n-hexane, EtOAc 및 n-BuOH로 극성별 순차 용매 분획을 실시하였고, 얻어진 결과물에 대하여 DPPH와 ABTS+ radical 소거능 및 최종당화물 생성 저해활성을 평가 하였다. 먼저 DPPH 라디칼 소거활성은 페놀성 화합물의 함량이 상대적으로 높은 n-BuOH 가용부에서 IC50값이 24.3±1.7 μg/mL 으로 우수한 DPPH 라디칼 소거능을 확인하였고, 곤드레 추출물에 존재하는 페놀성 화합물과 라디 칼 소거능과의 연관성을 시사하였다. 또한 ABTS+ 라디칼 소거능은 EtOAc 및 n-BuOH 분획층물의 IC50값은 각각 69.5±2.6 μg/mL, 25.0±3.3 μg/mL의 라디칼 소거활성이 확인 되었고, 우수한 라디칼 소거 활성물질의 존재가 시사되었 다. 또한, 최종당화물 생성 저해활성을 측정한 결과, n-BuOH 가용분획에서 IC50값이 46.0±1.5 μg/mL로 높은 생 성저해활성을 나타내었으며, 이는 positive control인 aminoguanidine의 IC50값인 90.2±3.2 μg/mL과 비교해볼 때 우수한 활성이었으며, 다양한 화합물이 공존하는 추출물 상태의 시료를 단일물질로 정제할 경우 더욱 우수한 효능의 화합물이 존재할 가능성을 시사하였다. 향후 이들 활성물 질 동정을 통한 활성물질의 구조 결정 및 활성 기작에 대한 연구가 필요하며 본 연구결과는 천연물 유래의 라디칼 소거 능 및 AGEs 생성 저해능을 가지는 새로운 천연 기능성소재 발굴을 위한 기초자료로 활용가능하리라 사료된다.