Bioconverted Jeju Hallabong tangor ( Citrus kiyomi × ponkan ) peel extracts by cytolase enhance antioxidant and anti-inflammatory capacity in RAW 264.7 cells

作者：Yun-Hee Chang, Jieun Seo, Eunju Song, Hyuk-Joon Choi, Eugene Shim, Ok‐Hee Lee, Jinah Hwang · 发表于：Nutrition Research and Practice · 年份：2016 · DOI：10.4162/nrp.2016.10.2.131 · 被引用次数：15 · 研究领域：Food Quality and Safety Studies、Phytochemicals and Antioxidant Activities、Polysaccharides and Plant Cell Walls

BACKGROUND/OBJECTIVES: Citrus and its peels have been used in Asian folk medicine due to abundant flavonoids and usage of citrus peels, which are byproducts from juice and/or jam processing, may be a good strategy. Therefore, the aim of this study was to examine antioxidant and anti-inflammatory effects of bioconversion of Jeju Hallabong tangor (Citrus kiyomi × ponkan; CKP) peels with cytolase (CKP-C) in RAW 264.7 cells. MATERIALS/METHODS: Glycosides of CKP were converted into aglycosides with cytolase treatment. RAW 264.7 cells were pre-treated with 0, 100, or 200 µg/ml of citrus peel extracts for 4 h, followed by stimulation with 1 µg/ml lipopolysaccharide (LPS) for 8 h. Cell viability, DPPH radical scavenging activity, nitric oxide (NO), and prostagladin E2 (PGE2) production were examined. Real time-PCR and western immunoblotting assay were performed for detection of mRNA and/or protein expression of pro-inflammatory mediators and cytokines, respectively. RESULTS: HPLC analysis showed that treatment of CKP with cytolase resulted in decreased flavanone rutinoside forms (narirutin and hesperidin) and increased flavanone aglycoside forms (naringenin and hesperetin). DPPH scavenging activities were observed in a dose-dependent manner for all of the citrus peel extracts and CKP-C was more potent than intact CKP. All of the citrus peel extracts decreased NO production by inducible nitric oxide synthase (iNOS) activity and PGE2 production by COX-2. Higher dose of CKP and all CKP-...