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31.
Recently, cancer chemoprevention with strategies using foods and medicinal herbs has been regarded as one of the most visible fields for cancer control. Genistein in soy, American ginseng, and resveratrol are well-known to have antiproliferative properties in human breast cancer. Licorice root is a botanical, a shrub native to southern Europe and Asia, which primarily has desirable qualities in sweetening and herbal medicine. In this study, licorice (Glycyrrhiza uralensis Fisch) root also inhibits cell proliferation in human breast cancer cell. The cell proliferation study demonstrated that licorice root reduced the proliferation of MCF-7 cells in a dose- and time-dependent manner. The extracts were fractionated in CHCl(3), EtOAc, C(6)H(14), and CH(3)OH-H(2)O (70:30), and these extracts of licorice root (50 microg/mL) induced DNA fragmentation demonstrated by Hoechst 33258 staining. Apoptosis also determined the sub-G1 accumulation by flow cytometry analysis. These results were consistent with specific cleavage of PARP and antiapoptotic protein Bcl-2 and up-regulation of proapoptotic protein Bax demonstrated by Western blotting. Our findings suggest that licorice root may have chemopreventive effects against human breast cancer through the modulation of the expression of the Bcl-2/Bax family of apoptotic regulatory factors.  相似文献   
32.
The toxic effects of Eucalyptus globulus leaf oil-derived monoterpenoids [1,8-cineole, l-phellandrene, (-)-alpha-pinene, 2-beta-pinene, trans-pinocarveol, gamma-terpinene, and 1-alpha-terpineol] and the known Eucalyptusleaf oil terpenoids (beta-eudesmol and geranyl acetate) on eggs and females of the human head louse, Pediculus humanus capitis, were examined using direct contact and fumigation bioassays and compared with the lethal activity of delta-phenothrin and pyrethrum, two commonly used pediculicides. In a filter paper contact bioassay with female P. h. capitis, the pediculicidal activity was more pronounced with Eucalyptus leaf oil than with either delta-phenothrin or pyrethrum on the basis of LT(50) values (0.125 vs 0.25 mg/cm(2)). 1,8-Cineole was 2.2- and 2.3-fold more toxic than either delta-phenothrin or pyrethrum, respectively. The pediculicidal activities of (-)-alpha-pinene, 2-beta-pinene, and (E)-pinocarveol were comparable to those of delta-phenothrin and pyrethrum. l-Phellandrene, gamma-terpinene, and 1-alpha-terpineol were relatively less active than delta-phenothrin and pyrethrum. beta-Eudesmol and geranyl acetate were ineffective. 1-alpha-Terpineol and (E)-pinocaveol were highly effective at 0.5 and 1.0 mg/cm(2), respectively, against P. h. capitis eggs. At 1.0 mg/cm(2), (-)-alpha-pinene, 2-beta-pinene, and gamma-terpinene exhibited moderate ovicidal activity, whereas little or no ovicidal activity was observed with the other terpenoids and with delta-phenothrin and pyrethrum. In fumigation tests with female P. h. capitis at 0.25 mg/cm(2), 1,8-cineole, (-)-alpha-pinene, (E)-pinocarveol, and 1-alpha-terpineol were more effective in closed cups than in open ones, indicating that the effect of the monoterpenoids was largely due to action in the vapor phase. Neither delta-phenothrin nor pyrethrum exhibited fumigant toxicity. Eucalyptus leaf oil, particularly 1,8-cineole, 1-alpha-terpineol, and (E)-pinocaveol, merits further study as potential pediculicides or lead compounds for the control of P. h. capitis.  相似文献   
33.
We developed a simple approach to combine broad classes of dissimilar materials into heterogeneously integrated electronic systems with two- or three-dimensional layouts. The process begins with the synthesis of different semiconductor nanomaterials, such as single-walled carbon nanotubes and single-crystal micro- and nanoscale wires and ribbons of gallium nitride, silicon, and gallium arsenide on separate substrates. Repeated application of an additive, transfer printing process that uses soft stamps with these substrates as donors, followed by device and interconnect formation, yields high-performance heterogeneously integrated electronics that incorporate any combination of semiconductor nanomaterials on rigid or flexible device substrates. This versatile methodology can produce a wide range of unusual electronic systems that would be impossible to achieve with other techniques.  相似文献   
34.
The growth-inhibiting activity of Coptis japonica (Makino) root-derived materials toward eight human intestinal bacteria was examined using an impregnated paper disk method and compared to that of four commercially available isoquinoline alkaloids [berberine sulfate (BS), berberine iodide (BI), palmatine chloride (PC), and palmatine sulfate(PS)], as well as that of Thea sinensis leaf-derived epigallocatechin gallate (EGCG). The biologically active constituents of the Coptis extract were characterized as the isoquinoline alkaloids berberine chloride (BC), palmatine iodide (PI), and coptisine chloride (CC) by spectral analysis. The growth responses varied with both chemical and bacterial strain used. In a test using 500 microg/disk, BC and PI produced a clear inhibitory effect against Bifidobacterium longum, Bifidobacterium bifidum, Clostridium perfringens, and Clostridium paraputrificum, whereas weak or no inhibition was observed in Bifidobacterium adolescentis, Lactobacillus acidophilus, Lactobacillus casei, and Escherichia coli. At 1000 microg/ disk, CC revealed weak or no growth inhibition toward all test bacteria, whereas EGCG exhibited weak growth inhibition against only C. perfringens and C. paraputrificum. Among various isoquinoline alkaloids, BC exhibited more potent inhibitory activity toward C. perfringens than BI and BS, whereas the inhibitory effect was more pronounced in PI compared to PC and PS. The Coptis root-derived materials did not promote growth of B. longum and C. perfringens.  相似文献   
35.
It has been reported that soybean peptide fractions isolated from Korean fermented soybean paste exert angiotensin I converting enzyme (ACE) inhibitory activity in vitro. In this study, further purification and identification of the most active fraction inhibiting ACE activity were performed, and its antihypertensive activity in vivo was confirmed. Subsequently, a novel ACE inhibitory peptide was isolated by preparative HPLC. The amino acid sequence of the isolated peptide was identified as His-His-Leu (HHL) by Edman degradation. The IC(50) value of the HHL for ACE activity was 2.2 microg/mL in vitro. Moreover, the synthetic tripeptide HHL (spHHL) resulted in a significant decrease of ACE activity in the aorta and led to lowered systolic blood pressure (SBP) in spontaneously hypertensive (SH) rats compared to control. Triple injections of spHHL, 5 mg/kg of body weight/injection resulted in a significant decrease of SBP by 61 mmHg (p < 0.01) after the third injection. These results demonstrated that the ACE inhibitory peptide HHL derived from Korean fermented soybean paste exerted antihypertensive activity in vivo.  相似文献   
36.
Brassica oleracea L. includes various types of important vegetables that show extremely diverse phenotypes. To elucidate the genetic diversity and relationships among commercial cultivars derived by different companies throughout the world, we characterized the diversity and genetic structure of 91 commercial B. oleracea cultivars belonging to six varietal groups, including cabbage, broccoli, cauliflower, kohlrabi, kale and kai-lan. We used 69 polymorphic microsatellite markers showing a total of 359 alleles with an average number of 5.20 alleles per locus. Polymorphism information content (PIC) values ranged from 0.06 to 0.73, with an average of 0.40. Among the six varietal groups, kohlrabi cultivars exhibited the highest heterozygosity level, whereas kale cultivars showed the lowest. Based on genetic similarity values, an UPGMA clustering dendrogram and a two-dimensional scale diagram (PCoA) were generated to analyze genetic diversity. The cultivars were clearly separated into six different clusters with a tendency to cluster into varietal groups. Model-based structure analysis revealed six genetic groups, in which cabbage cultivars were divided into two subgroups that were differentiated by their head shape, whereas cauliflower and kai-lan cultivars clustered together into a single group. Furthermore, we identified 18 SSR markers showing 27 unique alleles specific to only one cultivar that can be used to discriminate 22 cultivars from the others. Our phylogenetic and population structure analysis presents new insights into the genetic structure and relationships among 91 B. oleracea cultivars and provides valuable information for breeding of B. oleracea species. In addition, we demonstrate the utility of SSR markers as a powerful tool for discriminating between the cultivars. The SSR markers described herein will also be helpful for Distinctness, Uniformity and Stability (DUS) test of new cultivars.  相似文献   
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This paper presents the synthesis of metal complex acid dyes obtained from the reaction of o,o′-dihydroxyazo dyes and chromium and cobalt sulfate. The 1H-NMR, FT-IR and UV/Visible Spectrophotometer, TLC (Thin Layer Chromatography) and ICP (Ion Chromatography) of the intermediates and the metal complexes were studied and compared. Their properties such as dyeing, fastness and toxicity on nylon were also assessed according to standard methods.  相似文献   
40.
Standard extraction procedure for examining chromophoric substances of turmeric was investigated. Acetone and methanol were used as extracting solvents with different extraction procedures and pH levels. GC-MS analysis identified curcumene2 (6.7 min), feruloylmethane3 (8.3 min), coumaran4 (6.09 min), vanillin5 (6.2 min), and zingiberene6 (10.5 min) as the major products. Curcumin1 which has been known as the major chromophoric substance of turmeric was not detected in any samples. The maximum amount of curcumene2, which was used as the fingerprint product for turmeric dye, was obtained by utilizing presoaking and decanting step with methanol prior to actual extraction step using a waterbath shaker (WMM). The highest relative abundance of curcumene2 was detected in pH 6 sample followed by pH 5 indicating that the most appropriate pH level was in the range of pH 6–5. This research was funded by the 2004 Research Fund of University of Incheon.  相似文献   
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