This study was conducted to investigate the effect of manufacturing temperature on curcuminoid contents and the antioxidant activity of turmeric (Curcuma aromatica Salab.) powder-enhanced nurungji. Two different processes employed turmeric powder (2%): AR (added after rice cooked) and BR (added before rice cooked). AR and BR nurungji samples were prepared by heating cooked rice at 180oC, 200oC, and 220oC for 3 minutes. As a result of the HPLC analysis, the contents of curcumin, demethoxycurcumin, and bisdemethoxycurcumin decreased as the heating temperature increased. Moreover, AR samples showed higher curcuminoids than BR samples. The total polyphenol contents, DPPH, and ABTS radical scavenging ability proportionally increased with the increase of the manufacturing temperature. On the other hand, flavonoid contents were decreased with increasing temperature. These results suggest that the preparation of turmeric powder-enhanced nurungji by AR process at 200oC is preferable to preserving curcuminoid contents and antioxidative activity.

This study was conducted to investigate the total polyphenol, total flavonoid and the antioxidant activity in different origin and parts of Moringa olerifera cultivated in Cheorwon. The extraction yield from leaf, root and stem were 25.5, 23.0, 12.3%, respectively. The total polyphenol content was high in the leaf extracts (15.77 mg/g) followed by root extracts (11.23 mg/g) and stem extracts (3.50 mg/g) but the difference of origin was not observed. The total flavonoid content was high in the leaf extracts (14.78 mg/g) followed by stem (1.36 mg/g) and root (1.14 mg/g). The total flavonoid content of Philippines and Thailand leaf were statistically high compared to india leaf. The DPPH radical scavenging activity was high in the leaf extracts at the 1 mg/ml, 0.25 mg/ml but the difference of origin was not observed. The DPPH radical scavenging activity may be attributed to the presence of several compounds such as polyphenol and flavonoid. Hence consumption of diet supplemented with Moringa olerifera leaves could protect the human against diseases induced by oxidative stress.

Background : Buckwheat (Fagopyrum spp.) is an annual crop belonging to the polygonaceae family and cultivated in most of Asian and European countries. Nowadays, many people take interest in the utilization of buckwheat seed because of its high nutritional and pharmaceutical values. Especially, tartary buckwheat is drawing attention for its high rutin content, which is beneficial to health. Methods and Results :　Tartary buckwheat sprout (TBS) was powdered and two grams of powder was mixed with 4 ㎖ H2O in a glass petri disc (100 x 20 ㎜) and exposed to far infrared irradiation (FIR) at different temperature (80, 100, 120, 140, 160℃) for an hour each. Further, the FIR treated powdered sprout samples were suspended in 200 ㎖ of 80% ethanol (v/v) and kept overnight in a shaker at room temperature. The extracts were filtered through Advantec 5B Tokyo Roshi Kaisha Ltd., Japan and dried using a vacuum rotatory evaporator (EYLA N-1000, Tokyo, Japan) in a 40℃ water bath. Dried samples were weighed and kept at 4℃ for further analysis. Conclusion : Total polyphenol was evaluated by Folin-Ciocalteau assay and total flavonoid by aluminum nitrate colorimetric assay, while antioxidant properties were evaluated based on DPPH free radical scavenging activity, metal chelating property and total antioxidant capacity. This study showed that FIR treatment to TBS caused a decrease in total antioxidant capacity and metal chelation property. However, there was a slight increase in total polyphenol and total flavonoid content from 80 to 120℃. Similarly, DPPH free radical scavenging activity also increased in the same way as TP and TF in TBS. The HPLC result revealed that quercetin production was directly proportional to temperature, and the production (average 14.87 ㎎/g dw) of quercetin was highest at 120℃ (an hour’s treatment), which was 13.54 times higher than the control in TBS.

Background : Invitro antioxidant activity, polyphenol and flavonoid aglycone contents in black and green tea products of balloon flower leaves were investigated to provide valuable information for the further development and utilization of resources of Platycodon grandiflorum. Methods and Results : Flavonoid aglycone contents were investigated using HPLC (SHIMADZU, Japan) with a hypersil ODS column (125 mm × 4 mm, 5-μm particle, HP). DPPH and ABTS radical scavenging activities were measured by method of Lee & Lee (2004) with slight modification. Antioxidant activity, polyphenol and flavonoid contents in green tea were significantly higher than these in black tea. PC analysis indicated that first principal components explained 79.9% of the total variability for five traits investigated. PC2 explained 19.7% of the variation. Conclusion : It can be concluded from these results that these characteristics can reveal the active compound variation of black and green tea products of balloon flower leaves. These results provide scientific evidence for the utilization of balloon flower leaves.

This study purposed to look for its uses by analyzing useful substances in kenaf (Hibiscus cannabin us L.) leaves based on the total polyphenol and flavonoid contents in the leaves, DPPH radical scavenging activity of leaf extract, SOD activity, etc. by different growth stage and variety. According to the results of experiment, the total polyphenol content was highest in Everglade-41 (27.9 mg/g dw.), the total flavonoid content was highest in Tainung-2 (42.3 mg/g dw.), and SOD activity was highest in Dowling (96.1 %). However, DPPH radical scavenging activity was similar among the three varieties.