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121.
Lee JH Lee KT Akoh CC Chung SK Kim MR 《Journal of agricultural and food chemistry》2006,54(15):5416-5421
Structured lipid (SL) was synthesized from extravirgin olive oil (EVOO) and conjugated linoleic acid (CLA) via a lipase-catalyzed reaction. CLA provides a variety of health benefits, but it is not consumed in free fatty acid form. The synthesized SL olive oil contained 42.5 mol % CLA isomers, and the major isomers were cis-9,trans-11-CLA (16.9 mol %) and trans-10,cis-12-CLA (24.2 mol %). The antioxidant activity determined by the radical scavenging capacity with the 2,2-diphenyl-1-picrylhydrazyl radical was lower in SL olive oil than in EVOO. The oxidative stability was also lower in SL olive oil since it had a higher peroxide value, rho-anisidine value, and 2-thiobarbituric acid reactive substances values during 20 days of storage at 60 degrees C. This observation could be due to the reduction in the natural phenolic compounds (97%) and tocopherols (56%), and the incorporated CLA with two conjugated double bonds in the SL olive oil. The oxidative stability of SL olive oil was increased by added rosemary extracts at concentrations of 100, 200, and 300 ppm. The present study suggests that the SL olive oil may be a suitable way to incorporate or deliver CLA into human diets. However, the addition of a proper antioxidant would be required for improving its oxidative stability. 相似文献
122.
Used with one of two surfactants (SDS, an anionic surfactant, and Triton X-100, a nonionic surfactant), the ligand, I? was evaluated as a washing agent for the desorption of Cd from naturally and artificially contaminated soils. Increasing amounts of the ligand, I?, with a surfactant, specifically removes higher levels of Cd but not Cu, Zn and Pb. After seven washings, the ligand, I? with the nonionic surfactant, Triton X-100, removed 65 and 90% of the Cd from soils I and II, containing respectively, to 15 and 1275 mg of Cd/kg. The ligand, I?, and the anionic surfactant, SDS, removed 35 and 70% of the Cd from soils I and II, respectively. Before washing, the carbonate fraction of soil I contained the most Cd (48%) while the exchangeable and carbonate fractions of soil II contained 29 and 33% of the total Cd, respectively. For soil I, SDS with/ without the ligand desorbed Cd mainly from the carbonate and oxide fractions, while only Triton X-100 with ligand I? could remove Cd from the exchangeable fraction. For soil II, Cd was desorbed from the exchangeable fraction only when either surfactant was used in combination with the ligand. Thus, a surfactant with ligand can extract specific heavy metals from soils and selective sequential extraction is useful in identifying which fraction can be targeted by the surfactant – ligand agent. 相似文献
123.
Hong SY Kim JY Ahn HY Shin JH Kwon O 《Journal of agricultural and food chemistry》2012,60(12):3086-3091
Nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) is a fundamental regulator of systemic blood pressure. Ginsenosides from Panax ginseng have been investigated in vitro for the molecular and biochemical mechanisms by which they stimulate NO release in vascular endothelial cells; however, little research has been done to confirm the physiological relevance of these in vitro studies. To address this research gap, the effects of a P. ginseng extract rich in ginsenosides from protopanaxatriol on spontaneously hypertensive rats (SHRs) was examined. Ginseng extract administration stimulated nongenomic Akt-mediated eNOS activation, enhanced NO production, improved vessel wall thickening, and alleviated hypertension in SHRs, confirming the physiological relevance of previous in vitro studies with ginsenosides. 相似文献
124.
Isolation and characterization of a new compound from Prunus mume fruit that inhibits cancer cells 总被引:1,自引:0,他引:1
An active compound that inhibits cancer cells was isolated from the fruit of Prunus mume, and its structure and in vitro activities were characterized. The n-hexane fraction obtained from methanol extracts exhibited the strongest inhibitory effect on the growth of cancer cells. From the n-hexane fraction, a new compound named B-1 was purified through preparative thin-layer chromatography, ODS column chromatography, and reverse phase high-performance liquid chromatography and its structure was analyzed by fast atom bombardment mass spectrometry and 1H and 13C NMR. The molecular formula of B-1 was C19H22O6 {2-hydroxy-1-[(7-hydroxy-2-oxo-2H-chromen-6-yl)methyl]-2-methylpropyl-(2Z)-3-methyl-but-e-enoate:prunate}, and the IC50 value was in the range of 39-58 microg/mL in descending order of the cancer cell lines Hep-2, SW-156, HEC-1-B, and SK-OV-3. B-1 exhibited 81-96% inhibition at a concentration level of 100 microg/mL against all cells, based on an 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. However, B-1 showed little effect against normal cells with only 23% or less growth inhibition at 100 microg/mL. Thus, B-1 has a highly specific inhibitory effect against cancer cells but little effect against normal cells. When the cancer cell lines Hep-2 and SK-OV-3 were incubated with B-1 for 72 h, most of the tested cells suffered strong growth inhibition. The compound has the potential to be developed as a nutraceutical. 相似文献
125.
126.
Various pigment colors were produced by Monascus fermentations with separate addition of 20 amino acids. The color characteristics and structures of the pigment derivatives were investigated. When each amino acid was added to the fermentation broth as a precursor, pigment extracts with different hue and chroma values were obtained depending on the content ratios of yellow, orange, and red colors in the fermentation broth. The yellow and orange pigments were identical regardless of amino acid addition. The red compounds varied on the basis of the type of amino acid added. LC-MS and (1)H and (13)C NMR structural analyses confirmed that the derivative pigments contained the moieties of the added amino acids. L, a, and b values of the CIELAB color system for the derivative pigments were measured. Values of hue and chroma were then calculated. The colors of the derivative pigments were in the range of orangish red to violet red. The hydrophilicities/hydrophobicities of the derivative pigments could be predicted from their log P values, which were estimated using computer programs. 相似文献
127.
Shin C Hyun J Lim Y Kim JS Jang YM Kang SJ 《Journal of agricultural and food chemistry》2011,59(21):11579-11584
In this study, a derivative of p-phenoxybenzaldehyde in bamboo shoots was investigated. Bamboo shoots were ground and extracted with water, and an aqueous suspension was purified by SPE using Oasis HLB cartridges. After the SPE procedure, the analytes were analyzed by HPLC with refractive index detection (HPLC-RI). In the HPLC-RI analysis for sucralose, a putative sucralose was detected. In the subsequent HPLC-PDA analysis, the suspicious peak showed a unique UV absorption spectrum with the maximum wavelength at 285 nm indicating the existence of an aromatic ring. The contents of the unknown compound in bamboo shoot products ranged from 0.01 to 0.15 mg/g. The identity of the unknown compound was further confirmed by HPLC-ESI/MS/MS. The molecular weight of the unknown compound was determined to be 244. The chemical structure of the unknown compound was elucidated on the basis of NMR spectroscopic analyses ((1)H, (13)C, DEPT, COSY, HMQC, and HMBC). Finally, the structure of the unknown compound was characterized as 4-(4-dihydroxymethylphenoxy)benzaldehyde. 相似文献
128.
Yoshimi Sakai Shin Ugawa Shigehiro Ishizuka Masamichi Takahashi Chisato Takenaka 《Soil Science and Plant Nutrition》2013,59(4):526-537
Estimating carbon (C) and nitrogen (N) stocks in deadwood in forests nationwide is required for understanding large-scale C and N cycling. To do so requires estimated values of wood density and C and N concentrations. Additionally, parameters that show variation should be examined. In this study, we clarified the estimated values and the variation in three parameters in each decay class of each of two tree species and examined whether dead log diameter and region contribute to variation in the parameters. Data were collected from 73 Chamaecyparis obtusa (Sieb. et Zucc.) Endl. plantations and 66 Cryptomeria japonica D. Don plantations throughout Japan. Wood densities decreased from 386 to 188?kg?m?3 for C. obtusa and from 334 to 188?kg?m?3 for C. japonica in decay classes 1–4. The variation in wood density increased with decay class, and the coefficient of variance increased from 13.9% to 46.4% for C. obtusa and from 15.2% to 48.1% for C. japonica. The N concentrations increased from 1.04 to 4.40?g?kg?1 for C. obtusa and from 1.11 to 2.97?g?kg?1 for C. japonica in decay classes 1–4. The variation in N concentration increased with decay class, and the coefficient of variance increased from 51.9% to 76.7% for C. obtusa and from 50.3% to 70.4% for C. japonica. Log diameter and region contributed to variations in wood density and N concentration in decay classes 1 and 2 for C. obtusa and C. japonica. However, no relationship was observed between regional climates and the two parameters. In contrast, C concentrations ranged from 507 to 535?g?kg?1 and were stable with much lower coefficients of variance throughout the decay classes for both tree species. Thus, we recommend that the same C concentration can be adapted for all decay classes of both tree species. 相似文献
129.
130.
Chen‐Wuing Liu Ching‐Chieh Lin Cheng‐Shin Jang Guey‐Rong Sheu Lo Tsui 《植物养料与土壤学杂志》2009,172(4):550-556
Poultry litter is widely used as a fertilizer for lowland rice in Taiwan and China. However, the organic‐arsenic compound roxarsone (additive of poultry feed) in poultry litter can be absorbed by the plants and the resulting arsenic (As) contamination may pose a serious threat to human health. This study used various amounts of poultry litter contaminated with roxarsone in pot experiments to evaluate the effect of roxarsone on rice agronomic parameters and the bioaccumulation of total and inorganic As in rice‐plant tissues. Rice‐grain yield decreased significantly with increasing As content of the soil, and the critical threshold that killed rice was 200 mg roxarsone (kg soil)–1. The As concentrations in root, straw, leaf, husk, and grain increased with increasing soil As (p < 1%). At 100 mg roxarsone per kg of soil, the As concentration in the rice grain exceeded the statutory permissible limit of 1.0 mg As (kg dry weight)–1 and at 25 mg roxarsone (kg soil)–1, the inorganic As concentrations in grains exceeded the statutory limit of 0.15 mg of inorganic As kg–1 in China. For all treatments, the As concentrations in various plant tissues at maturity follow the order: root > stem > leaf > husk > grain. Arsenite was the predominant species in root, straw, and grain, while arsenate was the predominant species in leaf and husk. No significant difference existed between the amounts of arsenite and arsenate when various amounts of poultry litter were applied. This result illustrates that large amounts of added roxarsone are not only toxic to rice but also accumulate in grains in the inorganic As forms, potentially posing a threat to human health via the food chain. 相似文献