The antioxidant capacities, total phenolic contents (TPC), and total quercetin contents (TQC) of a red (Chenjujuck), a yellow (Sunpower), and a white (Grasier) onion cultivar were determined in this study. Onion was separated into edible portion and dry skin. In the case of edible portion, the yellow onion had the highest antioxidant activity, followed by the red onion. The white onion showed neither antioxidant activity nor quercetin compounds. On the other hand, the dry skin of the red onion showed higher antioxidant activity than yellow onion skin. The white onion skin had slight antioxidant activity, low TPC, and no quercetin compounds. In addition, the flavonoid compounds of the edible portion and dry skins of these colored onions were analyzed by UFLC(ultra-fast liquid chromatography). The major compounds were quercetin 3,4-diglucoside and quercetin 4- glucoside in yellow and red onion edible portion, whereas the major compounds in yellow and red onion skins were quercetin 4- glucoside, quercetin, and quercetin 3,4-diglucoside.

This study compared the antioxidant activity and functional constituents of the peel, flesh,and placenta of oriental melons according to the harvest time. The sample oriental melons were harvested during the major harvest time (from June to August) and divided into peel, flesh, and placenta. To examine the antioxidant activity and functional constituents, the sample melons were extracted using EtOH. As a result, the functional constituents and antioxidant activity of the oriental melons were found to change according to the harvest time. The total phenol and total flavonoid contents were highest in the samples harvested in June, and lowest in the samples harvested in July. Meanwhile, the antioxidant activities were estimated using an ABTS and FRAP assay, where the samples harvested in June also showed the strongest the antioxidant potential, while the samples harvested in July showed significantly lower antioxidant activities. This means that the climate influences the synthesis of secondary metabolites. The above data also suggests that oriental melons harvested in June contain more functional phytochemicals, making them more beneficial for human health.

Red ginseng marc (RGM) has been used on primary industries using fertilizer or forage, and it mostly has been dumped. To improve utilization of RGM, the biological activities of RGM were examined. RGM was extracted and fractionated using various solvents and their biological activities were compared. The hexane fraction from the methanol extract of RGM (RGMMH) showed strong anti-cancer activity (58.56 ± 6.04% at 100 ㎍/mL) and anti-inflammatory effect (65.72 ± 1.33% at 100 ㎍/mL). But, oil extract of RGM extracted with hexane (RGMH) showed low activities (anti-cancer: 16.42 ± 3.33%, at 100 ㎍/mL, anti-inflammatory activity: 29.46 ± 2.10%, at 100 ㎍/mL). Their metabolites were analyzed using HPLC. Panaxydol known as anti-cancer compound of RGM was one of major compounds in RGMMH. Meanwhile, panaxydol was detected in trace amount in red ginseng marc oil (RGMH). In addition, RGMMH and RGMH showed big differences in HPLC profiling. This research suggests optimal extraction method of RGM oil.