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31.
32.
Zeolites are crystalline nanoporous aluminosilicates widely used in industry. In order for zeolites to find applications as innovative materials, they need to be organized into large two- and three-dimensional (2D and 3D) arrays. We report that uniformly aligned polyurethane films can serve as templates for the synthesis of uniformly aligned 2D and possibly 3D arrays of silicalite-1 crystals, in which the orientations of the crystals are controlled by the nature of the polymers. We propose that the supramolecularly organized organic-inorganic composites that consist of the hydrolyzed organic products and the seed crystals are responsible for this phenomenon. 相似文献
33.
Ae Kyung Lee Young Hee Joung Xue Wei Wu Heoy Kyung Jung C. John Burk Laurie L. Sanders Mark S. Roh Jeung Keun Suh 《Scientia Horticulturae》2011
A population of hybrids between Arisaema triphyllum subsp. stewardsonii and A. dracontium was investigated using molecular markers to document the hybrid origin. Total genomic DNA was extracted from A. triphyllum, A. dracontium, and the hybrids, and subjected to sequence analysis of various regions of intergenic spacer and genes of chloroplast or intergenic spacer and genes of nuclear ribosome for single nucleotide polymorphisms (SNPs). Clustering was performed using the unweighted pair group method with averages (UPGMA) tested by bootstrap (BS). Hybrid origin could not be easily confirmed in some regions. However, dendrograms constructed with a combined sequence analysis of A. triphyllum 26S ribosomal RNA gene [sequence identification (SI) 467] plus A. tortuosum phytochrome C-like (phyC) gene (SI 468) were very similar to dendrograms constructed from sequences of all regions. This suggests that selecting SI 467 and SI 468 would be practical to identify hybrid origins involving two parental species. Clustering of hybrids together with the female parent in most target regions suggests that, in Arisaema, cpDNA is considered maternally inherited. 相似文献
34.
Cha KH Lee JY Song DG Kim SM Lee DU Jeon JY Pan CH 《Journal of agricultural and food chemistry》2011,59(16):8670-8674
Chlorella is a nutrient-rich microalga that contains protein, lipid, minerals, vitamins, and high levels of lutein. This study evaluated the bioavailability of lutein from Chlorella vulgaris using a coupled in vitro digestion and human intestinal Caco-2 cell model. Lutein bioaccessibility was low, and approximately 75% of total C. vulgaris lutein was not micellized during the digestion process but remained in the insoluble digestate. Microfluidization improved lutein micellization efficiency during C. vulgaris digestion. C. vulgaris was microfluidized at a pressure exceeding 10000 psi, and the cell surface disruption was visualized by scanning electron microscopy. The mean C. vulgaris particle size was reduced from 3.56 to 0.35 μm with the microfluidization treatment. C. vulgaris microfluidization at 20000 psi was three times more efficient for aqueous lutein micelles production as compared with untreated C. vulgaris, and the final lutein content accumulated by intestinal Caco-2 cells was also higher with microfluidization. C. vulgaris lutein stability was not affected by microfluidization. These results indicate that microfluidization may be useful for improving lutein bioaccessibility from C. vulgaris during food processing. 相似文献
35.
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
36.
Yuan Wang Jing Ji Tae-Kyun Oh Sung Oh Sue Hoon Kim Hyun Ju Lee Myoung Yong Shim Chang Won Choi Seong Hwan Kim Il-Seop Kim Young Shik Kim 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(3):361-370
Two newly emerged begomoviruses were isolated from naturally infected tomato (Solanum lycopersicum) plants grown in greenhouses at Jeju Island and Dangjin in Korea and their genomes were characterized. These viruses-infected plants had very small leaves that curled upward, yellow margins and a leathery appearance, and a bushy and stunted appearance with short internodes. Nucleotide (nt) sequence analysis of their genomes showed that they have a DNA-A component of a monopartite begomovirus. Their genomes comprised 2763 and 2764 nucleotides with six open reading frames. The results of nt sequence similarity analysis of DNA-A genome between the two Korean isolates and isolates of Tobacco leaf curl Japan virus (TbLCJV), Honeysuckle yellow vein virus (HYVV), Honeysuckle yellow vein mosaic virus (HYVMV), and Eupatorium yellow vein virus in Japan (EpYVV) showed that they are likely similar to HYVV-[Masuda] (89.4–92.8% nt identity). Consequently, we tentatively propose the two isolates’ names as HYVV-Jeju and -DJ according to the ICTV geminivirus rules. Phylogenetic relationship analysis of 33 DNA-A genome sequences using PAUP* 4.0b10 and MrBayes revealed that HYVV-Jeju and -DJ belong to the Far East Asian begomovirus species complex. Within the Far East Asian begomovirus species complex, HYVV-Jeju and -DJ are distantly related to EpYVV, HYVMV, and TbLCJV groups. Based on the presence of a recombination fragment spanning the C3 ORF, a recombinant origin was suggested for both HYVV-Jeju and –DJ, with parents close to Japanese isolates HYVMV-[SP1:00] and Eupatorium yellow vein virus (EpYVV)-[Suya]. In addition, the presence of a further recombination fragment spanning the IR suggested the parents of HYVV-DJ were close to HYVV-Jeju and EpYVV-[Suya]. 相似文献
37.
Kim DO Heo HJ Kim YJ Yang HS Lee CY 《Journal of agricultural and food chemistry》2005,53(26):9921-9927
The identification of phenolics from various cultivars of fresh sweet and sour cherries and their protective effects on neuronal cells were comparatively evaluated in this study. Phenolics in cherries of four sweet and four sour cultivars were extracted and analyzed for total phenolics, total anthocyanins, and their antineurodegenerative activities. Total phenolics in sweet and sour cherries per 100 g ranged from 92.1 to 146.8 and from 146.1 to 312.4 mg gallic acid equivalents, respectively. Total anthocyanins of sweet and sour cherries ranged from 30.2 to 76.6 and from 49.1 to 109.2 mg cyanidin 3-glucoside equivalents, respectively. High-performance liquid chromatography (HPLC) analysis revealed that anthocyanins such as cyanidin and peonidin derivatives were prevalent phenolics. Hydroxycinnamic acids consisted of neochlorogenic acid, chlorogenic acid, and p-coumaric acid derivatives. Glycosides of quercetin, kaempferol, and isorhamnetin were also found. Generally, sour cherries had higher concentrations of total phenolics than sweet cherries, due to a higher concentration of anthocyanins and hydroxycinnamic acids. A positive linear correlation (r2 = 0.985) was revealed between the total anthocyanins measured by summation of individual peaks from HPLC analysis and the total anthocyanins measured by the pH differential method, indicating that there was in a close agreement with two quantifying methods for measuring anthocyanin contents. Cherry phenolics protected neuronal cells (PC 12) from cell-damaging oxidative stress in a dose-dependent manner mainly due to anthocyanins. Overall results showed that cherries are rich in phenolics, especially in anthocyanins, with a strong antineurodegenerative activity and that they can serve as a good source of biofunctional phytochemicals in our diet. 相似文献
38.
Methylation methods for the quantitative analysis of conjugated linoleic acid (CLA) isomers in various lipid samples 总被引:8,自引:0,他引:8
Park SJ Park CW Kim SJ Kim JK Kim YR Park KA Kim JO Ha YL 《Journal of agricultural and food chemistry》2002,50(5):989-996
Precise methylation methods for various chemical forms of conjugated linoleic acid (CLA), which minimize the formation of t,t isomers and allylmethoxy derivatives (AMD) with the completion of methylation, were developed using a 50 mg lipid sample, 3 mL of 1.0 N H(2)SO(4)/methanol, and/or 3 mL of 20% tetramethylguanidine (TMG)/methanol solution(s). Free CLA (FCLA) was methylated with 1.0 N H(2)SO(4)/methanol (55 degrees C, 5 min). CLA esterified in safflower oil (CLA-SO) was methylated with 20% TMG/methanol (100 degrees C, 5 min), whereas CLA esterified in phospholipid (CLA-PL) was methylated with 20% TMG/methanol (100 degrees C, 10 min), followed by an additional reaction with 1.0 N H(2)SO(4)/methanol (55 degrees C, 5 min). Similarly, CLA esterified in egg yolk lipid (CLA-EYL) was methylated by base hydrolysis, followed by reaction with 1.0 N H(2)SO(4)/methanol (55 degrees C, 5 min). These results suggest that for the quantitative analysis of CLA in lipid samples by GC, proper methylation methods should be chosen on the basis of the chemical forms of CLA in samples. 相似文献
39.
Antioxidative, antimutagenic, and anticarcinogenic activities of rice bran extracts in chemical and cell assays 总被引:4,自引:0,他引:4
Nam SH Choi SP Kang MY Kozukue N Friedman M 《Journal of agricultural and food chemistry》2005,53(3):816-822
Ethanol-water (70:30 v/v) extracts from rice brans removed from seeds of two blackish-purple pigmented (Sanhaehyanghyulla and Suwon 415) and one nonpigmented (Chuchung) brown rice cultivars were evaluated for antioxidative, anti-tumor-promoting, and anticarcinogenic activities in chemical assays and in mammalian cells (human leukemia HL-60, marmoset B lymphoblastoid B95-8, and Chinese hamster V79 lung cells) by the following tests: inhibition of xanthine oxidase activity; chelation of ferrous ions; reduction of potassium ferricyanide; scavenging of superoxide anions, hydroxyl radicals, and intracellular peroxides; inhibition of 4-nitroquinoline N-oxide-induced mutagenesis; and inhibition of phorbol ester-induced tumor promotion. The extracts from the pigmented rice seeds had generally higher activities in all tests than did the extract from the nonpigmented variety. The results suggest that brans from pigmented rice varieties may provide a source of new natural antioxidants and anticarcinogens and that such rice cultivars with high antioxidative potential also provide a genetic resource for the development of new, improved rice cultivars that may make it possible to enhance both the nutritional and medical value of rice-based diets. 相似文献
40.
Kim JH Lee JS Song KS Kwon CS Kim YK Kim JS 《Journal of agricultural and food chemistry》2004,52(3):451-455
Induction of cellular phase 2 detoxifying enzymes is associated with cancer preventive potential. Quinone reductase (QR) has been used as a prototype for anticarcinogenic phase 2 enzymes because of its widespread distribution in mammalian systems, large amplitude of inducer response, and ease of measurement in murine hepatoma cells. Methanol extract of Polyozellus multiplex, which shows a strong QR induction potential, was subjected to bioassay-guided fractionation, and polyozellin (PM1) appeared to be a major active component. In in vitro cultured cells (hepa1c1c7 and BPRc1 cells), polyozellin enhanced QR, glutathione S-transferase (GST) activities, and glutathione (GSH) content in a dose-dependent manner. The compound also significantly promoted differentiation of HL-60 human promyelocytic emia cells. In conclusion, polyozellin deserves further in vivo study to evaluate its potential as a cancer preventive agent. 相似文献