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51.
Mei Jing Piao Kyoung Ah Kang Rui Zhang Dong Ok Ko Zhi Hong Wang Keun Hwa Lee Weon Young Chang Sungwook Chae Youngheun Jee Taekyun Shin Jae Woo Park Nam Ho Lee Jin Won Hyun 《Food chemistry》2009
The antioxidant potential of 1,2,3,4,6-penta-O-galloyl-β-d-glucose (PGG), isolated from Elaeocarpus sylvestris var. ellipticus, was investigated by various established systems based on cell-free and cell system experiments, such as radical detection, antioxidant enzyme assay, lipid peroxidation detection, and cell viability assay. PGG was found to quench the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species. PGG recovered the cellular antioxidant enzyme activities of superoxide dismutase, catalase, and glutathione peroxidase, which were reduced by H2O2 treatment, thereby resulting in the inhibition of lipid peroxidation. Cytoprotective effects of PGG were based on the results of DNA fragmentation, mitochondrial membrane potential (Δψ), apoptotic body formation, and caspase-3 activity. The results suggest that PGG protects cells against H2O2-induced cell damage via antioxidant properties. 相似文献
52.
Kyung Hoon Chang Se-Ho Park Hee-Sook Jee Kee-Tae Kim Hyun-Dong Paik Joo-Yeon Lee 《Food science and biotechnology》2014,23(1):173-178
White ginseng extract (WGE) was hydrolyzed with organic acids to increase the yield of ginsenoside Rg3 which has high bio-functional activities. The condition of hydrolysis by citric acid was studied to maximize a production of ginsenoside Rg3. The total content of ginsenoside Rg3 in WGE treated with 10% citric acid at 110°C for 1 h was 10-folds greater than that of commercial extract. The antitumor and antioxidant activities of WGE and the acid-hydrolysates were evaluated via an MTT assay and the DPPH method, respectively. At 1.0 mg/mL, hydrolysates inhibited the proliferation of AGS and Hep-2 cells by more than 90%, but did not inhibit their growth. It suggests that citric acid hydrolysis enhances the content of Rg3. In addition, the acid hydrolysates evidenced a free radical scavenging activity of 80% at a concentration of 4.0 mg/mL, while WGE exhibited only a 49% free radical scavenging activity at the same concentration. 相似文献
53.
Teh SJ Deng X Deng DF Teh FC Hung SS Fan TW Liu J Higashi RM 《Environmental science & technology》2004,38(22):6085-6093
The chronic effects of dietary selenium (Se) exposure in juvenile Sacramento splittail (Pogonichthys macrolepidotus) were investigated in the laboratory. A total of 960 (40 fish per tank, 3 tanks per diet) 7-month-old juvenile splittail were fed one of eight Purified-Casein diets supplemented with selenized yeast for 9 months in a flow-through system. These diets contained the following: 0.4 (control), 0.7, 1.4, 2.7, 6.6, 12.6, 26.0, and 57.6 mg of Se kg(-1) dry weight. Survival, Se tissue concentration, growth, gross morphology, and liver histopathology were assessed at 5- and 9-month of exposure. Mortalities occurred only in the two highest Se treatments and were accounted for 8.3 and 18.3% at 5-month and 10.0 and 34.3% at 9-month, respectively. Liver and muscle Se concentration were significantly correlated with dietary Se concentration. Fish exposed to 0.4-12.6 mg of Se kg(-1) diets had reached equilibrium in liver Se concentration by 5 month. Splittail fed diets at concentrations > or =26.0 mg of Se kg(-1) had not reached equilibrium in liver, and muscle Se concentrations and grew significantly slower (p < 0.05) at 5- and 9-month exposure. Se-induced deformities were observed in fish fed > or =2.7 mg of Se kg(-1) diets at 5-month and in fish fed > or =0.7 mg of Se kg(-1) diets at 9-month. Fish fed 26.0 and 57.6 mg of Se kg(-1) diets had higher liver lesion scores at 5-month while fish fed 6.6 and 57.6 mg of Se kg(-1) diet had higher liver lesion scores at 9-month. Results indicate that survivals, growth, changes of tissue Se concentrations, and histopathology of juvenile splittail were dose-dependent, but their response thresholds to dietary Se concentrations differed and depended on treatment concentrations and duration of exposure. Chronic exposure to 6.6 mg of Se kg(-1) diet induced deleterious health effects that can potentially impact survival of juvenile splittail. 相似文献
54.
S.J. Eom J.E. Hwang J. Jung H.-S. Jee K.-T. Kim H.-D. Paik 《Journal of dairy science》2017,100(10):7788-7792
Ginseng marc, a by-product of the extraction of fresh ginseng, is known to have bioactive compounds, but is frequently discarded as agriculture waste. The objectives of our study were to assess the antioxidative activity of fermented ginseng marc extract using Lactobacillus plantarum KCCM 11613P and to evaluate antibacterial activity of fermented milk with added ginseng marc extract during fermentation. After 24 h of fermentation of ginseng marc extract, the viable cell number was increased to 7.7 ± 0.1 log cfu/mL, and the pH and total titratable acidity were 4.2 ± 0.4 and 0.6% lactic acid, respectively. The total phenolic and flavonoid contents of fermented ginseng marc extract increased by 32.4 and 23.3%, respectively. Higher antioxidative activity of fermented ginseng marc extract was obtained in the β-carotene bleaching, ferric-reducing ability of plasma, and ferric thiocyanate assays than the 1,1-diphenyl-2-picrylhydrazy assay. However, the 1,1-diphenyl-2-picrylhydrazy scavenging effect decreased due to lowered pH. During production of fermented milk with ginseng, inhibition rate of Staphylococcus aureus and Escherichia coli were 9.7 and 2.3%, respectively. The present study shows the possibilities of Lactobacillus plantarum KCCM 11613P used as a fermentation strain and ginseng marc used as a functional supplement in milk. 相似文献
55.
The objective of this study was to control the survival or biofilm formation of Cronobacter spp. on stainless steel surfaces using Paenibacillus polymyxa. The antibacterial activity of a cell‐free culture supernatant (CFCS) of P. polymyxa against Cronobacter spp. was found to vary with P. polymyxa incubation time. Maximum activity occurred when P. polymyxa was incubated at 25 or 30 °C for 96 h. When the CFCS was introduced to Cronobacter spp. adhered to stainless steel strips at 25 °C for up to 72 h, the CFCS successfully inhibited Cronobacter biofilm formation. Additionally, stainless steel surfaces with a preformed P. polymyxa biofilm were exposed to Cronobacter spp. suspensions in PBS or 0.1% peptone water at 3, 5, or 7 log CFU/mL to facilitate its attachment. The Cronobacter population significantly decreased on this surface, regardless of inoculum level or carrier, when the P. polymyxa biofilm was present. However, the microbial population decreased within 6 h and remained unchanged thereafter when the surface was immersed in an inoculum suspended in 0.1% peptone water at 5 or 7 log CFU/mL. These results indicate that P. polymyxa is able to use a promising candidate competitive‐exclusion microorganism to control Cronobacter spp. 相似文献
56.
Cho Woohyeon Jung Jin-Kee Kang Min-Young Seo Yong Weon Park Jee Young Yang Tae-Jin 《Food science and biotechnology》2022,31(4):423-431
Food Science and Biotechnology - Wheat (Triticum aestivum) has diverse uses in the food industry, and different cultivars have unique properties; therefore, it is important to select the optimal... 相似文献
57.
Different concepts and designs of photovoltaic thermal (PV/T) collectors were developed for the past few decades to improve the electrical and thermal efficiencies. Several of those designs have become successful and are being commercialized along with other solar collectors. This paper discusses the experimental studies on a novel PV/T water-based collector constructed by laminating the PV cells on a copper thermal absorber. This modification reduced the thermal resistance by 9.93 %, thereby enabling better heat transfer from the PV cells to the heat transfer fluid. Water was passed through a single water channel connected to an open reservoir. Experiments were conducted with and without glazing, with two different water mass flow rates and stagnant conditions, and with load and no-load conditions and thermal stress test. Results show that an overall efficiency of 87.52 % was achieved in the presence of glazing at a mass flow rate of 0.1 kg/s. Few conformance tests according to IEC standards are also presented to check the electrical insulation and structural integrity of the PV/T collector. 相似文献
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Light Harvesting: Enhanced Light Harvesting in Mesoscopic Solar Cells by Multilevel Multiscale Patterned Photoelectrodes with Superpositioned Optical Properties (Adv. Funct. Mater. 36/2016) 下载免费PDF全文