• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.481-487
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• 2010

The nutritional components, antioxidant, and neuroprotective effects of water and a 50% methanol extract from litchi fruit pericarp were investigated. The most abundant mineral, amino acid, and fatty acid were K, proline, and palmitic acid, respectively. In addition, the total water phenolics and 50% methanol extracts were 8.02 and 12.28 mg/g, respectively. The DPPH, ABTS radical scavenging activities and ferric reducing antioxidant power of the water and 50% methanol extracts showed dose-dependent antioxidant activity. In a cell viability assay using MTT, almost all extracts showed a protective effect against $H_2O_2$-induced neurotoxicity, and lactate dehydrogenase leakage was also inhibited by the pericarp extracts. In particular, the 50% methanol extract showed a higher cell membrane protective effect than the water extract at the highest concentration. Consequently, these data suggest that litchi fruit pericarp can be utilized as an effective and safe functional food substances for natural antioxidants and may reduce the risk of neurodegenerative disorders.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.17-25
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• 2013

This study was performed to investigate the effects of the hot water extract of red garlic (RG) and RG-composites on fecal lipid levels and hepatic antioxidant enzyme activity in rats fed a high fat-cholesterol diet. Three different types of RG-composites prepared: RG and green tea (RGT), RG and dietary fiber (RGF), and RG, green tea, and dietary fiber (RGTF). Rats were divided into six groups: the control, the group fed a high fat-cholesterol diet (HFC), the RG-supplemented group (HRG), the RGT supplemented group (HRGT), the RGF supplemented group (HRGF), and the RGTF supplemented with HFC group (HRGTF). The antioxidant activity of these composites was tested, in vitro. The DPPH radical scavenging activity was higher RGT and RGTF than RG. ABTs radical scavenging activity of RGT was similar to RGTF. Their activities were significantly higher than RG. The reducing power was similar to their radical scavenging activities. Total lipid levels in the liver and triglyceride levels in the heart were lower in the groups fed RG-composites than the HRG group. Fecal total lipid level was higher in the HRGF and HRGTF groups than the HRG group after 4 weeks diet supplementation during 4 weeks. Lipid peroxide content was reduced to anywhere between 6.2% and 12.1% in the groups fed RG-composites, compared to the HFC group. Antioxidant activity was significantly higher in the groups fed RG-composites than the HFC group. Hepatic SOD activity was higher in the groups fed RG-composites than the HRG group. The HRGT group in catalase activity, and the HRGT and HRGTF groups in GSH-px activity were increased significantly compared to the HFC group. Hepatic UDPGT activity was increased significantly in the HRGT and HRGTF groups to the HFC group, as well. These results indicate that antioxidant activities of the RG-composites were related to the decrease of lipid levels by increasing the fecal excretion and enhancement of hepatic antioxidant enzyme activity in rats fed a high fat-cholesterol diet.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.4
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• pp.347-350
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• 2011

Biofilms are surface-attached microbial communities with phenotypic and biochemical properties distinct from free-living planktonic cells. Biofilm bacteria show much greater resistance than planktonic counterparts and much higher concentration of biocide is needed to treat biofilms compared to the dosage used for planktonic bacteria. As a result, alternative strategies or more effective agents exhibiting activity against biofilm-producing micro-organisms are of great interest. Therefore, we turned our attention to control of biofilm of S. aureus. The aims of this research are to investigate substances which inhibit the formation of biofilm by S. aureus and to suggest effective materials for controlling skin problems. We coated slide glasses with human placental collagen and the coverslip was incubated with test materials and bacteria. The coverslip was stained with crystal violet and we measured optical density of each sample. The biofilm inhibitory activity was calculated by crystal violet staining degrees. In this study, S. aureus ATCC 6538 was used as test organism. Our results show that both water soluble and insoluble Hinoki cypress polysaccharide strongly inhibited biofilm formation. Whereas, green tea and sunset hibiscus root extract promoted biofilm. Xylitol showed a concentration dependent effect; high concentration (3 % and 5 %) of xylitol reduced biofilm while promoted biofilm formation at a concentration of 1 %. These results support that Hinoki cypress polysaccharide and xylitol have ability to suppress biofilm formation.