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71.
Flavonol glycosides and novel iridoid glycoside from the leaves of Morinda citrifolia 总被引:5,自引:0,他引:5
Sang S Cheng X Zhu N Stark RE Badmaev V Ghai G Rosen RT Ho CT 《Journal of agricultural and food chemistry》2001,49(9):4478-4481
One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM. 相似文献
72.
Sato D Awad AA Chae SH Yokota T Sugimoto Y Takeuchi Y Yoneyama K 《Journal of agricultural and food chemistry》2003,51(5):1162-1168
A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively. 相似文献
73.
New prenylated benzoic acid and other constituents from almond hulls (Prunus amygdalus Batsch). 总被引:2,自引:0,他引:2
Shengmin Sang Karen Lapsley Robert T Rosen Chi-Tang Ho 《Journal of agricultural and food chemistry》2002,50(3):607-609
One new prenylated benzoic acid derivative, 3-prenyl-4-O-beta-D-glucopyranosyloxy-4-hydroxylbenzoic acid, and three known constituents, catechin, protocatechuic acid, and ursolic acid, have been isolated from the hulls of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the new prenylated benzoic acid derivative were accomplished on the basis of high-resolution 1D and 2D nuclear magnetic resonance data. All of these compounds except ursolic acid are being reported from almond hulls (P. amygdalus) for the first time. 相似文献
74.
Sang S Zou M Xia Z Lao A Chen Z Ho CT 《Journal of agricultural and food chemistry》2001,49(10):4780-4783
Three new spirostanol saponins have been isolated from the seeds of Allium tuberosum. On the basis of acid hydrolysis and comprehensive spectroscopic analysis, their structures were established as tuberoside J, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside; tuberoside K, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside; and tuberoside L, 27-O-beta-D-glucopyranosyl-(25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-D-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside. 相似文献
75.
Four new steroidal saponins from the seeds of Allium tuberosum 总被引:3,自引:0,他引:3
Four new steroidal saponins, 26-O-beta-D-glucopyranosyl-(25S,20R)-20-O-methyl-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (1); 26-O-beta-D-glucopyranosyl-(25S,20R)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (2); 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (3); and 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-3beta,20,26-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (4), have been isolated from the seeds of Allium tuberosum. Their structures were established by spectroscopic studies such as MS, IR, NMR, and 2D-NMR and the results of acid hydrolysis and named tuberosides F, G, H, and I, respectively. 相似文献
76.
Sang S Kikuzaki H Lapsley K Rosen RT Nakatani N Ho CT 《Journal of agricultural and food chemistry》2002,50(16):4709-4712
One sphingolipid, 1-O-beta-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2R)-2-hydroxyhexadecanoylamino]-4,8-octadecadiene-1,3-diol, and four other constituents, beta-sitosterol, daucosterol, uridine, and adenosine, have been isolated from the nuts of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the sphingolipid were accomplished on the basis of high-resolution 1D and 2D NMR data. All of these compounds are being reported from almond nuts (P. amygdalus)for the first time. 相似文献
77.
Anushka Upamali Rajapaksha Meththika Vithanage Sang Soo Lee Dong-Cheol Seo Daniel C. W. Tsang Yong Sik Ok 《Journal of Soils and Sediments》2016,16(3):889-895
Purpose
Sulfamethazine (SMT) is increasingly detected in environmental matrices due to its versatile use as antibiotics. We aimed to investigate the benefits and roles of steam activation of biochars with respect to SMT sorption kinetics and equilibrium sorption.Materials and methods
Biochars were produced from burcucumber plant and tea waste using a pyrolyzer at a temperature of 700 °C for 2 h. The biochar samples were treated with 5 mL min?1 of steam for an additional 45 min for post-synthesis steam activation. The SMT sorption on the unmodified and steam activated biochars were compared.Results and discussion
The time taken to reach equilibrium was significantly less for steam activated biochars (~4 h) than non-activated biochars (>24 h). Up to 98 % of SMT could be removed from aqueous solutions by steam activated biochars. The sorption kinetic behaviors were well described by the pseudo-second model and SMT sorption rates of steam activated biochars (k 2?~?1.11–1.57 mg g?1 min?1) were significantly higher than that of the unmodified biochars (k 2?~?0.04–0.11 mg g?1 min?1) because of increased availability of accessible porous structure with averagely larger pore diameters. Moreover, the equilibrium sorption on the unmodified biochars was significantly influenced by increasing solution pH (~30–50 % reduction) because of speciation change of SMT, whereas steam activated biochars manifested much stronger sorption resilience against pH variation (~2–4 % reduction only) because the enhanced porosity offset the effect of unfavorable electrostatic repulsion.Conclusions
The observed features of steam activated biochars would render their applications more versatile and reliable in field throughout changeable environmental conditions.78.
79.
Davis EG Sang Y Rush B Zhang G Blecha F 《Veterinary immunology and immunopathology》2005,105(1-2):163-169
NK-lysin is an antimicrobial peptide of cytotoxic and NK lymphocytes that has powerful antibacterial properties as well as antitumoral activity. Here we report the full-length cDNA and deduced amino acid sequence for equine NK-lysin. Equine NK-lysin is 67% identical to porcine NK-lysin, 53% identical to bovine NK-lysin and 41% identical to granulysin in amino acid sequence. Complete conservation of cysteine residues between equine, bovine and porcine NK-lysin suggests similar disulfide bonding patterns among these peptides. Equine NK-lysin has the most positive surface charge when compared with other homologues. Similar to expression profiles in other species, equine NK-lysin is constitutively transcribed in various lymphocytes that include CD4+ and CD8+ staining cells. These findings suggest that equine NK-lysin, similar in cDNA sequence to the porcine, bovine and human homologues may play a role in antimicrobial defense. 相似文献
80.
Park ES Seong JK Yi SJ Kim JS Lee HS Lee IS Yoon YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):639-646
This study was carried out to investigate the changes of orexin-A (OXA) and neuropeptide Y (NPY) expression in the hypothalamus of the obese and lean Zucker Diabetic Fatty (ZDF) rats which have a missense mutation in the leptin receptor gene. The mean body weights (MBW) between the obese and lean ZDF rats were significantly different at 28 and 70 postnatal days. However, at 14 postnatal day, there was no significant difference in the MBW between the obese and lean ZDF rats in both male and female. The OXA immunoreactivities were not significantly different between the obese and lean ZDF rats in both sexes at 14, 28, and 70 postnatal days, respectively. The NPY immunoreactivity was higher in the obese than in the lean ZDF rats in both male and female at 28 and 70 postnatal days, whereas there was no significant difference between the obese and lean ZDF rats at 14 postnatal day. These results indicate that both OXA and NPY might halt their roles for food intake in the obese phenotype of the male and female ZDF rats in the preweaning period of 14 postnatal day, whereas NPY might play a main role in the obesity of these rats in the weaning period of 28 and 70 postnatal days. 相似文献