치자 씨의 에틸 아세테이트, 증류수 및 70% 메탄올(v/v)의 3가지 용매를 사용한 추출물의 용매 별 플라보노이드 함량 및 항산화 활성, 금속 킬레이트 능력 측정을 통하여 치자의 기능성 식품 재료로서의 가치를 검토하기 위하여 본 실험을 수행하였다. 치자 씨의 탄닌 함량은 1.517±0.003 mg CE/g (mg of catechin equivalents) 건조 중량으로 나타났으며, 치자 씨 용매 별 추출 수율은 증류수 (36.61%), 70% 메탄올(30.10%), 에틸아세테이트(20.40%) 순으로 나타났다. 추출 용매 별 항산화 활성은 농도(0.2, 0.4, 0.6 mg/mL)가 증가할수록 유의적으로 증가하였으며(p<0.05), 양성대조구로 사용된 ascorbic acid, BHA, EDTA 보다 낮은 활성이 관찰되었다. 플라보노이드 함량(mg QE/g, mg of quercetin equivalents)은 70% 메탄올(0.799), 증류수(0.565), 에틸아세테이트(0.117) 순으로 관찰되었으며, 항산화 활성은 대부분의 분석에서 용매 별 플라보노이드 함량 순과 비슷한 양상으로 나타났지만 ABTS 라디칼 소거능과 SOD 유사활성은 증류수 추출물이 70% 메탄올 추출물의 항산화 활성 보다 높은 것으로 나타났다. 치자 씨의 각 용매별 수율과 항산화 활성을 비교하였을 때, 증류수와 70% 메탄올 용매를 사용하여 추출 이용하는 것이 바람직하다고 생각된다. 본 실험 결과 치자 씨는 플라보노이드 화합물을 다량 함유하고 있으며 그로 인한 높은 수준의 항산화 활성과 생리활성을 가지고 있어 기능성 식품 및 천연 항산화제로서의 가치가 매우 기대된다.

Naringenin and its glycoside naringin (naringenin-7-O-glycoside) belong to this series of flavonoids and were well-known strong antioxidant activity. This study was conducted to flavonoid constituents and antioxidant activity of Pleurotus ostreatus and Pleurotus cornucopiae. In order to determine active ingredient contents of Pleurotus ostreatus and Pleurotus cornucopiae, we were carried out total polyphenolic content (TPC) and flavonoid content (TFC) analyses. As a result, TPC (31.05 ± 0.03 g GAE/kg extract) and TFC (13.25 ± 1.24 g NE/kg extract) of Pleurotus cornucopiae were found significantly higher as compared to Pleurotus ostreatus. The IC50 values based on the DPPH (56.50 ± 0.73 μg/ml) and ABTS (86.53 ± 3.86 μg/ml) for Pleurotus cornucopiae were generally stronger showing potential antioxidant properties compared to Pleurotus ostreatus. In addition, naringin and naringenin content were analyzed by high-performance liquid chromatography analysis. A great amount of naringin and naringenin was found in Pleurotus cornucopiae. These results indicate that the Pleurotus cornucopiae can be used as an antioxidant therapeutic agent.

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.

Total phenol contents, total flavonoid contents and antioxidant activity of 70% methanol, 70% ethanol and chloroform-methanol (CM, 2:1, v/v) extracts from onion (Allium cepa L.) peels were studied. The IC50 values of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical and ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity in 70% ethanol extract were remained to be lowest followed by 70% methanol extract and CM extract. And the total phenol content (113.56±0.86 mg CAE/g), total flavonoid content (49.63 mg QE/g) and ferric reducing antioxidant power value were also found to be the highest. In contrast, 70% methanol extract possessed the strongest antioxidant activity by β-carotene bleaching assay. CM extract displayed the lowest antioxidant activity compared with other extracts. Onion peels exhibited strong antioxidant activity and abundant phytochemicals, which could be used in a various food products to add phytochemicals and promote good health.

The present study were conducted to determine physiological activities and antioxidant effects [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, reducing power, Ferric Reducing Antioxidant Power (FRAP) and Fe2+ (ferrous ion) chelating capacity] of 70% methanol, chloroform:methanol, 2:1 volume ratio (CM) and ethyl acetate extract of turmeric (Curcuma longa L.). Bioactive compound of tannin 0.125±0.007 mg Catechin Equivalent (CE)/g dry weight. Turmeric extracts yield were 70% methanol 16.54%, CM 5.64% and ethyl acetate 4.14%, respectively. Antioxidant activity of the samples exhibited a dose-dependent increase. Results showed that extraction solvent had significant effects on total flavonoid content and antioxidant effects of ethyl acetate. But ferrous ion-chelating capacity of 70% methanol extract was higher than CM and ethyl acetate extract. From the results of this study, turmeric can be utilized as a valuable and potential nutraceutical for the functional food industry.

The purpose of this study was to measure the bioactivity and antioxidant activity of peel from Gardenia jasminoides fructus Ellis (GJE) in Namhae, Korea, following some established methods. CM (Chloroform:Methanol, 2:1, v/v), 70% ethanol, and n-butanol extracts were collected. Flavonoid content and value as a functional food ingredient of GJE peel was investigated through assessing antioxidant [DPPH (1,1'-diphenyl-2-picrylhydrazyl), ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid)], and hydroxyl radical scavenging activities; superoxide dismutase like ability; ferrous ion-chelating capacity; and tannin content by solvent extraction. Solvent extract antioxidant activities significantly increased (p<0.05) at increasing concentrations (0.2, 0.4, 0.6 mg/mL). GJE peel extracts were less active than the positive control [ascorbic acid, BHA (butylated hydroxyanisole), and EDTA (ethylenediaminetetraacetic acid disodium salt dihydrate)]. Based on the results of this study, GJE peel could be used as a natural antioxidant source due to its high antioxidant activity and bioactive compound content.

Background : Kenaf (Hibiscus cannabinus L.) is a member of the malvaceae family and has been prescribed in traditional folk medicine in Africa and India. It showed broad biologicas activities such as hepatoprotective activity, antioxidative activity and haematinic activity. Kenaf leaves contain a lot of vegetable calcium, protein, iron and vitamins, so have high potential as functional food. Thus, the present study purposed to analyze useful substances contained in kenaf leaves and their activities and look for their possibilities as the materials of food and medicine. Methods and Results :　We sowed the seeds of three varieties of kenaf, namely, Dowling, Everglade-41 and Tainung-2 at planting space of 20 × 20㎝ on the field and collected plants on the 98th , 127th and 141st days from sowing. The total polyphenol content was measured using a slightly modified Folin-Denis method, which uses the phenomenon that a phenolic substance turns blue by reaction with phosphomolybdate. Conclusion : We analyzed SOD enzyme activity related to the scavenging of superoxide anion radical (․O2-) through NBT reduction. As for the SOD activity of leaf extract by variety, the activity was 92.6%, 91.0% and 92.6%, respectively, in Tainung-2 on day 98, 127 and 141 from sowing, slightly higher than those in the other two varieties but not significantly different. The activity was slightly higher in the middle period of growth than in the harvest period, but not much different according to harvest time. As for the DPPH radical scavenging activity of leaf extract by variety, the activity was 80.87% and 80.71%, respectively, in Tainung-2 on day 98 (30th of October)and day127 (28th of September), slightly higher than the other two varieties.

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 : Kenaf (Hibiscus cannabinus L.) is a member of the malvaceae family and has been prescribed in traditional folk medicine in Africa and India. It showed broad biologicas activities such as hepatoprotective activity, antioxidative activity and haematinic activity, Recently, immunomodulatory effect of kenaf extract has been elucidated. However, depigmenting activity from kenaf extract has not been evaluated. In the present study, the tyrosinase inhibitory effect of kenaf leaf extract was investigated before and after subjecting the extract to together with infrared(FIR) irradiation. Methods and Results :　FIR irradiation involves electromagnetic waves with wavelengths ranging from 4 to 15 μM. It has been hypothesized that FIR treatment during extraction of polyphenols from plant cells stimulates exudation of chemical components in cells without destroying the cells by radiant heat and breaks covalent bonds of polymerized polyphenols resulting in the release of active, natural antioxidants with a low molecular weight. The purpose of this study was to evaluate not only the changes in antityrosinase activity but also the chemical transformation of kenaf extract exposed to FIR(Scheme 1). Conclusion: The tyrosinase inhibitory activity of kenaf xtract was evaluated after far-infrared (FIR) irradiation. The ethanol extract of kenaf was prepared and its main component was analyzed as a kaempferitrin (kaempferol-3,7-O-a-dirhamnoside). Inhibitory activity of kenaf extract was not detected in tyrosinase assay. However, tyrosinase inhibitory activity was observed in kenaf extract treated with FIR irradiation. After 60 min of FIR irradiation onto kenaf extract at 60oC, a ethanolic extract was prepared and it showed significant tyrosinase inhibitory activity (IC50=3500ppm). According to HPLC analysis, kaempferol, afzelin and minor product were detected(. The inhibitory activity may be due to the existence of kaemperol, afzelin and minor product. This study showed that FIR irradiation method can be used as a convenient tool for deglycosylation of flavonoid glycoside.