Time filter

Source Type

Jeong C.H.,Wooyang Frozen Food Co. | Bae Y.I.,Bio 21 Center | Park S.J.,Gyeongsang National University | Lee S.K.,Konkuk University | Hur S.J.,Konkuk University
Food Science and Biotechnology | Year: 2012

In order to obtain basic data required for utilization of guava leaf as a functional substance, the antioxidant activities of aqueous extracts from 3 cultivars of guava leaf ('Apple color', 'Ruby', and 'Safeda') were examined. The total phenolic contents of the aqueous extracts ranged from 257. 38 to 293. 25 mg/g gallic acid equivalents. DPPH, ABTS, reducing power, ferric reducing antioxidant power (FRAP), ferric thiocyanate (FTC), and malondialdehyde (MDA) assays indicated that the aqueous extract of the 'Ruby' cultivar was the most potent radicalscavenger and reducing agent compared to the other 2 cultivars. Therefore, this study verified that aqueous extract from the 'Ruby' cultivar possessed strong antioxidant activity that correlated to its high level of phenolics, particularly gallic acid. In conclusion, the aqueous extract of the 'Ruby' cultivar of guava leaf may be utilized as an effective source of functional food materials, including natural antioxidants. © 2012 The Korean Society of Food Science and Technology and Springer Science+Business Media Dordrecht.

Bae Y.-I.,Bio21 Center | Lee J.-W.,Bio21 Center | Ha T.J.,Bio21 Center | Hwang S.-H.,Bio21 Center | And 4 more authors.
Journal of the Korean Society of Food Science and Nutrition | Year: 2013

The nutrients and antioxidative activities of fruits and leaves from Metasequoia glyptostroboides were investigated to provide basic data for the future development of functional foods. The nitrogen-free extract contents of fruit and leaves were 69.04% and 50.47%, respectively. Total phenolic content was higher in leaves (21.75 mg/GAE g) compared to the fruit (19.95 mg/GAE g). The mineral components of fruit and leaves mainly consisted of calcium (2,136.08 and 304.85 mg/100 g, respectively), potassium (1,355.53 and 1,144.04 mg/100 g, respectively), and phosphorous (426.30 and 350.50 mg/100 g, respectively). In terms of amino acid composition, aspartic acid, glutamic acid, proline, and leucine were relatively high, but methionine and cystine were low. The hot water extract from leaves was a more potent free radical-scavenger and had higher reducing activities than extracts from fruit. Thus, phenolics of M. glyptostroboides leaves can be utilized as an effective functional food substance for its natural antioxidant properties.

Kim J.H.,Gyeongsang National University | Kim J.H.,Jeollanamdo Institute of Natural Resources Research JINR | Choi G.N.,Gyeongsang National University | Kwak J.H.,Gyeongsang National University | And 5 more authors.
Food Science and Biotechnology | Year: 2012

Antioxidant capacities (ABTS radical scavenging assay and ferric reducing/antioxidant power assay), mushroom tyrosinase inhibitory effect, and α-melanocyte stimulating hormone (α-MSH) induced melanogenesis inhibitory effect of 60% methanol extracts and ethylacetate fractions from chestnut inner skin in B16F10 cells were investigated to inspect whitening effect. Above research showed that 60% methanol extracts and ethylacetate fractions from chestnut inner skin resulted in a dose-dependent manner on in vitro antioxidant effects. Especially, the ethylacetate fractions inhibited enzyme activity of mushroom tyrosinases with an IC50 value of 160 μg/mL. Ethylacetate fractions from chestnut inner skin also decreased cellular melanin synthesis in B16F10 melanoma cells. Expression of tyrosinase showed that ethylacetate fractions from chestnut inner skin significantly decreased cellular melanogenesis. Consequently, these results suggest that chestnut inner skin extracts can be considered for a whitening agent of human skin. © 2012 The Korean Society of Food Science and Technology and Springer Science+Business Media Dordrecht.

Hur S.J.,Konkuk University | Bae Y.I.,Bio 21 Center | Kim Y.-C.,Korea Food Research Institute | Choi I.,Korea Food Research Institute | Jeong C.H.,Wooyang Frozen Food Co.
Current Topics in Nutraceutical Research | Year: 2013

This study was conducted to investigate the in vitro neuroprotective and antioxidative activities of aqueous loquat extract (LLE). The loquat leaf extracts inhibited lipid peroxidation and showed protective effects against H2O2-induced neurotoxicity in a dose-dependent manner. In the neuronal cell (PC 12) viability assay, LLE showed a protective effect against H2O2-induced neurotoxicity, and the release of lactate dehydrogenase (LDH) into the medium was also inhibited (28.94-52.09%). The total phenolic content of LLE was 42.55 mg/gallic acid equivalent (GAE) g, and the major phenolic compounds were rutin, epicatechin, and catechin. These data suggest that an LLE that includes the above phenolics may be useful as a natural antioxidant substance. Copyright © 2013 by New Century Health Publishers, LLC.

Hur S.-J.,Konkuk University | Park S.-J.,Gyeongsang National University | Jeong C.-H.,Wooyang Frozen Food Co.
Journal of Agricultural and Food Chemistry | Year: 2011

This study was conducted to investigate the effects of buckwheat (Fagopyrum esculentum Moench cv. Yangjul No. 2) extract on the antioxidant activity of lipids in mouse brain and the structural change during in vitro human digestion. Buckwheat was collected from a wild farm and extracted with water. The buckwheat extracts were then passed through an in vitro human digestion model that simulated the composition of the mouth, stomach, and small intestine juice. The results confirmed that the main phenolics of buckwheat extract were rutin, quercitrin, and quercetin. The rutin content increased with digestion of the buckwheat (from 48.82 to 96.34 μg/g) and rutin standard samples (from 92.76 to 556.56 μg/g). Antioxidant activity was more strongly influenced by in vitro human digestion of both buckwheat and rutin standard. After digestion by the small intestine, the antioxidant activity values were dramatically increased (from 5.06 to 87.82%), whereas the antioxidant activity was not influenced by digestion in the stomach for both buckwheat extract and rutin standard. Inhibition of lipid oxidation of buckwheat in mouse brain lipids increased after digestion in the stomach for both buckwheat extract and the rutin standard. The major finding of this study was that in vitro human digestion may be an important modulator of the antioxidant capacity of buckwheat and that this may be because in vitro human digestion increas d the antioxidative activity via an increase in antioxidants such as rutin and quercetin. © 2011 American Chemical Society.

Discover hidden collaborations