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排序方式: 共有159条查询结果,搜索用时 31 毫秒
61.
Chien SC Chen ML Kuo HT Tsai YC Lin BF Kuo YH 《Journal of agricultural and food chemistry》2008,56(16):7017-7022
Six new compounds, trans-3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]pyrrolidine-2,5-dione (1), trans-1-hydroxy-3-(4-hydroxyphenyl)-4-isobutylpyrrolidine-2,5-dione (2), cis-3-(4-hydroxyphenyl)-4-isobutyldihydrofuran-2,5-dione (3), 3-(4-hydroxyphenyl)-4-isobutyl-1H-pyrrole-2,5-dione (4), 3-(4-hydroxyphenyl)-4-isobutylfuran-2,5-dione (5), and dimethyl 2-(4-hydroxyphenyl)-3-isobutylmaleate (6), together with one known compound, 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]furan-2,5-dione (7), were isolated from the fruiting bodies of Antrodia camphorata. The structures of the compounds were elucidated by analysis of their spectroscopic data. To investigate the immunomodulatory potential of the compounds, RAW264.7 macrophage cells were treated with the compounds. Compound 1 significantly increased spontaneous TNF-alpha secretion from unstimulated RAW264.7 cells but suppressed IL-6 production [50% inhibition concentration value (IC50) = 10 microg/mL] in LPS-stimulated cells. Compounds 3, 4, and 6 also suppressed IL-6 production with IC50 values of 17, 18, and 25 microg/mL, respectively, suggesting that these four compounds may have an anti-inflammatory effect on macrophage-mediated responses. Of the six compounds, compound 1 was the most effective, exerting both immunostimulatory and anti-inflammatory effects. 相似文献
62.
This study was to investigate the effects of micronization on vitamin-carrying capacity and slow-release ability of carambola (starfruit) insoluble fiber (IF) and cellulose using in vitro and in vivomodels. Upon micronization, carambola IF (8.1 microm) underwent structural changes to expose more functional groups in the fiber matrix and to exhibit higher oil-holding capacity ( approximately 20.4-fold). Micronized fibers in forms of fiber-vitamin composites, particularly the micronized carambola IF-vitamin composite, were capable of carrying vitamin E (alpha-tocopherol) up to 9.6-fold over their unmicronized forms and releasing nutrient gradually. Animal studies demonstrated that the adminstration of micronized carambola IF-vitamin composite could maintain the plasma vitamin E of rats at relatively higher levels (2.1-3.6-fold of the initial values) for at least 5 h. The results suggested that micronized fibers, particularly the micronized carambola IF, could be exploited as potential nutrient carriers in food applications and also be used to produce slow-release formulations. 相似文献
63.
Hoang Huu Chien Maho Tokuda Dang Van Minh Yumei Kang Kozo Iwasaki Sota Tanaka 《Soil Science and Plant Nutrition》2019,65(1):73-81
This study investigated general physicochemical properties of tea garden soils at the alluvial plain of Cong River in Tan Cuong commune, Vietnam. Four gardens were selected as study sites on three transect lines established perpendicularly to the river. Soil samples were collected from the surface (0–10 cm) and subsurface (20–30 cm). Soil texture classes varied from sandy loam to light clay, which was affected by different terrains along the transect lines as well as severe disturbance such as terracing and earth excavation. The levels of total C and total N were correlated with increasing garden age, suggesting the replenishment of soil organic matter pool by the addition of plant residue and manure. Meanwhile, the soils showed strongly acidic nature with the average pH(H2O) of 3.7 at the surface and 3.9 at the subsurface. The effective cation exchange capacity (ECEC) was low at 4.7 and 4.9 cmolc kg?1, respectively, and dominated by exchangeable Al3+. Soil acidification was exacerbated with increasing garden age. However, a relatively large saturation of exchangeable calcium (Ca2+), potassium (K+), and magnesium (Mg2+) on the ECEC was found in the surface soils. The levels of available P were high, occasionally exceeding 1000 and 500 mg kg?1 at the surface and subsurface, respectively. In spite of strongly acidic condition, ammonium (NH4-N) applied as fertilizer was converted to nitrate (NO3-N) to move down to deeper layers. The levels of the bases, P, and mineral N seem to be principally determined by management practices. Significant portion of these nutrients was likely to exist in water soluble forms without adsorption onto soils. It should be required to develop proper schemes and to educate the owners for adequate fertilizer managements. 相似文献
64.
This paper presents the general principles and functions of asset management for irrigation and drainage infrastructure: Asset planning and creation strategies, operation and maintenance, performance monitoring, accounting and economics and audit and renewal analysis. The various elements of the program are conceptually defined and their application is illustrated with the asset management program (AMP) formulated for the La Khe Irrigation System in Vietnam. It also identifies the role of the AMP within the framework of service oriented management of irrigation and drainage services. An infrastructure and investment profile developed from the asset survey identified the investment requirement over the next 40 years. The analysis of cost of service and revenues shows a shortfall of US£17.00/ha/annum to meet the investment requirement over this period. The asset audit and renewal analysis shows the upgrades of the main system needed to improve the current level of service. 相似文献
65.
66.
Wilson BD Ii M Park KW Suli A Sorensen LK Larrieu-Lahargue F Urness LD Suh W Asai J Kock GA Thorne T Silver M Thomas KR Chien CB Losordo DW Li DY 《Science (New York, N.Y.)》2006,313(5787):640-644
Axonal guidance and vascular patterning share several guidance cues, including proteins in the netrin family. We demonstrate that netrins stimulate proliferation, migration, and tube formation of human endothelial cells in vitro and that this stimulation is independent of known netrin receptors. Suppression of netrin1a messenger RNA in zebrafish inhibits vascular sprouting, implying a proangiogenic role for netrins during vertebrate development. We also show that netrins accelerate neovascularization in an in vivo model of ischemia and that they reverse neuropathy and vasculopathy in a diabetic murine model. We propose that the attractive vascular and neural guidance functions of netrins offer a unique therapeutic potential. 相似文献
67.
Chiu YT Chiu CP Chien JT Ho GH Yang J Chen BH 《Journal of agricultural and food chemistry》2007,55(13):5123-5130
Tomato pulp waste, a byproduct obtained during the processing of tomato juice, has been shown to be a rich source of lycopene. The objectives of this study were to use gelatin and poly(gamma-glutamic acid) (gamma-PGA) as coating materials for the encapsulation of lycopene extract from tomato pulp waste. Initially, lycopene was extracted with supercritical carbon dioxide, followed by microencapsulation using an emulsion system consisting of 4.5% gelatin, 10% gamma-PGA, and 4.8% lycopene extract. Analysis of differential scanning calorimetry revealed that the thermal stability of the coating material could be up to 120 degrees C, with a mean particle size of 38.7 microm based on Coulter counter analysis. The total weight of microencapsulated powder was 617 microg with the yield of lycopene being 76.5%, indicating a 23.5% loss during freeze drying. During storage of microencapsulated powder, the concentrations of cis-, trans-, and total lycopene decreased along with increasing time and temperature. A fast release of lycopene in the powder occurred at pH 5.5 and 7.0, while no lycopene was released at pH 2.0 and 3.5. 相似文献
68.
Enhancing antioxidant, antiproliferation, and free radical scavenging activities in strawberries with essential oils 总被引:1,自引:0,他引:1
Wang CY Wang SY Yin JJ Parry J Yu LL 《Journal of agricultural and food chemistry》2007,55(16):6527-6532
Several natural antimicrobial compounds derived from essential oils of plants were investigated for their efficacies in inhibiting decay and extending the shelf life of strawberries (Fragaria x ananassas Duch.). The severity of decay in strawberries stored at 10 degrees C was significantly reduced by treatment with thymol. Treatments with menthol or eugenol also suppressed the fungal growth, but to a lesser extent. All of these three natural antimicrobial compounds extended shelf life of strawberries as compared to the control. Strawberries treated with thymol, menthol, or eugenol also maintained better fruit quality with higher levels of sugars, organic acids, phenolics, anthocyanins, flavonoids, and oxygen radical absorbance capacity than the untreated fruits. The free radical scavenging properties of strawberry fruit were evaluated against 2,2-diphenyl-1-picryhydrazyl (DPPH(.)), hydroxyl (HO(.)), and superoxide radicals (O2(.-)) using electron spin resonance measurements. Higher radical scavenging capacities were found against DPPH(.) and HO(.) in all treated fruit, particularly in berries treated with thymol, compared to those in the control groups. In addition, strawberry extracts were evaluated for their antiproliferative activities using HT-29 colon cancer cells. Extracts from all treated fruit exhibited significantly stronger inhibition on HT-29 cell proliferation than those from the control fruit. These data provide evidence that, in addition to possessing antimicrobial activity, the essential oils also increase free radical scavenging capacity and antiproliferative activity in fruit and, in turn, enhance the resistance of fruit tissues to deterioration and spoilage. 相似文献
69.
Curcumin, which is a bright orange-yellow pigment of turmeric with antioxidant properties, has been shown to produce a potent preventative action against several types of cancers in recent studies. It has also been reported to protect the development of colon tumor in animals being fed with carcinogen. In the colon cancer cells, curcumin was illustrated to inhibit cell proliferation and induce apoptosis. As an antioxidant, it acts as an anti-inflammatory as well as an antitumor agent. Curcumin has been detected to exist in nature in the form of curcuminoids, a mixture of curcumin, the major component, with two of its related demethoxy compounds (demethoxycurcumin and bisdemethoxycurcumin). In the present study, we have investigated the antiproliferation and induced apoptosis effects of curcuminoids on colon cancer, using the primary cancer cells isolated from Taiwanese colon cancer patients as the model for colorectal cancer. Results showed that curcuminoids inhibited cell proliferation and induced apoptosis of these human primary colon cancer cells. The effects were observed in a dose-dependent manner as dose increased from 12.5 to 100 microM. With the aim of furthering the fundamental understanding of the mechanisms underlying the antiproliferation and induced apoptosis effects of curcuminoids on these human colon cancer cells, we developed a sensitive, rapid, and reproducible assay method based on high-performance liquid chromatography (HPLC). This HPLC technique developed was found to successfully determine, in a quantitative manner, the cellular uptake of curcuminoids. The uptake of these curcuminoids by the colon cancer cells was shown to increase as the dose of curcuminoids was increased. The observations of inhibited proliferation and increased apoptosis in the colon cancer cells appeared to be associated with the cellular uptake of curcuminoids. 相似文献
70.
Liao YC Chang Chien SW Wang MC Shen Y Seshaiah K 《Journal of agricultural and food chemistry》2007,55(21):8640-8649
The relationship between Pb uptake by leaf lettuce ( Lactuca sativa L.) and water-soluble low-molecular-weight organic acids (LMWOAs) in rhizosphere, as influenced by transpiration (high and low), has been studied. Studies were carried out by culturing lettuce plants grown for 2 weeks in pots filled with quartz sand mixed with anion-exchange resin and then for 30 days in a greenhouse. The potted lettuce plants were subjected to stress by the addition of Pb(NO 3) 2 solutions (100, 200, and 300 mg of Pb L (-1)) and by high and low transpiration treatments for another 10-day period. Blank experiments (without addition of Pb(NO 3) 2 solutions to the pots) were also run. There were no significant differences in the growth of the plants with the addition of Pb(NO 3) 2 solutions in either of the transpirations studies. Uptake of Pb by the shoots and roots of the plants was found to be proportional to the concentration of Pb solutions added, and more accumulation was observed in the roots than in the shoots at the end of days 3 and 10. High transpiration caused more Pb uptake than did low transpiration. One volatile acid (propionic acid) and nine nonvolatile acids (lactic, glycolic, oxalic, succinic, fumaric, oxalacetic, d-tartaric, trans-aconitic, and citric acids) in rhizosphere quartz sand or anion-exchange resin were identified and quantified by gas chromatography analysis with a flame ionization detector. The amount of LMWOAs in rhizosphere quartz sand or anion-exchange resin increased with higher amounts of Pb in quartz sand solution and also with longer duration of the study. The total quantities of the LMWOAs in the rhizosphere quartz sand or anion-exchange resin were significantly higher under high and low transpiration with a 300 mg of Pb L (-1) solution addition at the end of day 10. Compared with our previous related studies (published work), the present study shows that the presence of LMWOAs in rhizosphere does not significantly affect Pb uptake by lettuce plants under high and low transpiration. A physiological mechanism of the roots of lettuce plants governing the relationship between Pb contamination level and quantity of water-soluble LMWOAs in rhizosphere quartz sand and resin, as influenced by transpiration, was proposed. 相似文献