• Food Science and Preservation
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• v.23 no.2
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• pp.283-289
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• 2016

Naturally occurring antioxidants, such as polyphenols are widely found in fruits, vegetables, wines, juices, and other plant-based dietary sources and are divided into several sub classes, including phenylpropanoids, flavonoids, stilbenoids, and lignans. As part of the our ongoing search for bioactive food ingredients, the antioxidant and advanced glycation end products (AGEs) formation inhibitory activities of the methanolic extract of the aerial parts of Cirsium setidens were investigated in vitro bioassay system. The antioxidant properties were evaluated through radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) ($ABTS^+$) radicals. In addition, the activity of C. setidens against diabetes complications was also tested via AGEs formation inhibition assay. The total phenolic contents were determined using a UV-VIS spectrophotometric method. All tested samples showed a dose-dependent radical scavenging and AGEs inhibitory activities. In particular, the n-butanol (BuOH)-soluble portion showed the most potent radical scavenging activities against DPPH and $ABTS^+$ radicals with $IC_{50}$ values of $24.3{\pm}1.7$ and $25.0{\pm}3.3{\mu}g/mL$, respectively. Futhermore, the inhibition of AGEs formation by the n-BuOH-soluble portion ($IC_{50}$ value; $46.0{\pm}1.5{\mu}g/mL$) was higher than that those of the soluble portions for the other solvent. The results showed that C. setidens could be considered as an effective source of natural antioxidants and other ingredients.

• Radiation Oncology Journal
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• v.19 no.3
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• pp.265-274
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• 2001

Purpose : Proctitis is one of acute complications encountered when radiotherapy was appled to the pelvis. Radiation-induced proctitis represents similar microscopic findings that are observed in inflammatory bowel disease (IBD). Nitric oxide (NO) plays an important role in the inflammatory process and many data suggest a close relationship between NO production and gastrointestinal inflammation. This study was aimed to establish the optimal radiation dose for radiation-induced proctitis in rat and to find a relationship between radiation proctitis and NO production. Materials and methods : Female Wistar rats, weighing from 150 to 220 g, received various doses(10-30 Gy) of radiation to the rectum. On the 5th and 10th day after irradiation, rectal specimens were evaluated grossly and microscopically. In addition, the degree of NO production by irradiation dose was evaluated by study with NOS expression and nitrite production in the irradiated rectal tissue. To evaluate relationship between radiation proctitis and NO, we administered aminoguanidine, iNOS inhibitor and L-arginine, substrate of NOS to rats from 2 days before to 7 days after the irradiation. Results : There were obvious gross and hostological changes after 17.5 Gy or higher radiation dose but not with 15 Gy or less radiation dose. Twenty Gy or higher dose of radiation caused Grade 4 damage in most of rectal specimens which were more likely to be related to the late complications such as fibrosis, rectal bleeding and rectal obstruction. A single fraction of 17.5 Gy to the rat rectum is considered to be an optimal dose to produce commonly experienced proctitis in the clinic. The result demonstrated that severity of microscopic damage of rectal mucosa from irradiation significantly correlated with iNOS over-expression. However, administration of iNOS inhibitor or substrate of iNOS did not influence the degree of rectal damage. Conclusion : A single fraction of 17.5 Gy irradiation to the rat rectum considered to be an optimal dose for radiation induced proctitis model. These results indicated that an excess production of NO contributes to pathogenesis of radiation-induced proctitis in part but was not the direct cause of rectal damage.