The present study aimed to evaluate the effects of roasting temperature on the quality characteristics and biological activity of quinoa. Quinoa was roasted at 160, 200, and 220oC for 20 min. The lightness (L*) of quinoa decreased, however, the redness (a*) increased as the roasting temperature increased. The yellowness (b*) was the highest at 160oC and decreased at 200 and 220oC. The highest contents of total polyphenol, flavonoid, and quercetin were observed at 220oC, the highest roasting temperature. The highest radical scavenging activities of 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (73.65%) and α,α-diphenyl-β-picrylhydrazyl free radicals (47.82%) were found in roasted quinoa at 220oC. The α- glucosidase activity was inhibited by 62.13% at this temperature. The roasted quinoa at 220oC also showed a significant cytoprotective effect against oxidative stress in HepG2 cells. These results could be useful in the development of food products using quinoa.

In this study, biotin (vitamin B7) contents of frequently consumed foods in Korea were determined by using immunoaffinity column in conjunction with high-performance liquid chromatography (HPLC). The biotin contents of 24 foods of plant origin and 27 foods of animal origin were selected. The highest biotin contents in frequently consumed foods of plant origin were found in red beans (Huinguseul; 11.475 μg/100 g). On the other hand, biotin was not detected in any varieties of sorghum. For frequently consumed foods of animal origin, salted pollack roe (7.486 μg/100 g) showed the highest biotin content. However, beef and fish contained less biotin. All biotin analyses were conducted under analytical quality control. The limits of detection and limits of quantification of biotin were 0.007 and 0.023 μg/100 g, respectively, and the accuracy/recovery percentage was 95.35-105.02%. The precision values were 4.041% (repeatability) and 3.835% (reproducibility). Taken together, our data provide reliable data on the biotin contents of frequently consumed foods in Korea.

As a result of development in medical diagnostic technology, the incidence of double primary cancer is increasing. In case that one primary cancer was identified by pathologic finding and has suggestive multiple metastatic lesions of the cancer, it is often difficult that the lesions are considered as another synchronous primary malignancy, not as metastasis of primary cancer. Here, we report a rare case of synchronous double primary renal cell carcinoma that was diagnosed initially as metastatic duodenal adenocarcinoma. A 66-year-old man presented with a palpable abdominal mass. Abdominal computed tomography showed duodenal wall thickening and hypervascular masses in the liver and left kidney. Esophagogastroduodenoscopy revealed an ulcerative lesion in the duodenal bulb, and endoscopic biopsy identified moderately-differentiated adenocarcinoma. We regarded the findings as duodenal adenocarcinoma with metastasis to liver and kidney. So he was treated with fluoropyrimidine-based chemotherapy for the diagnosis of duodenal adenocarcinoma with liver and renal metastases. After 10 months, he developed a right forearm mass. Morphological and immunohistochemical analysis of an incisional biopsy of the forearm mass were consistent with a diagnosis of metastatic renal cell carcinoma. Even when there is a pathologically confirmed malignancy, clinicians must consider the possibility of synchronous double primary malignancy in metastatic lesions.