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991.
Alshymaa Abdel-Rahman Gomaa Usama Ramadan Abdelmohsen Markus Krischke Martin J. Mueller Amira Samir Wanas 《Natural product research》2020,34(18):2612-2615
AbstractThe present study evaluates the chemical composition of Zinnia elegans and Gazania rigens based on their metabolomic profiles using liquid chromatography coupled with high-resolution mass spectrometry (LC‐HR-MS), alongside with the anti-infective activities of their ethanol extracts, as well as, different fractions. A significant difference was observed between the LC-MS profiles of the two plants such as, coumarins, sesquiterpene lactones and phenylethanoids which were characteristic for Z. elegans, while amides and phenolic acid derivatives were characteristic for G. rigens. These results highlight the chemical potential of Z. elegans and G. rigens. Furthermore, the ethyl acetate fraction of Z. elegans showed a significant antimalarial activity with IC50 values of 21.03 and 13.72?µg/mL against Plasmodium falciparum D6 and P. falciparum W2, respectively. 相似文献
992.
Alexsandra Conceição Apolinário Antonio Diogo Silva Vieira Susana Marta Isay Saad Adalberto Pessoa Jr José Alexsandro da Silva 《Natural product research》2020,34(16):2367-2371
Abstract This work aimed at evaluating the prebiotic potential of the aqueous extract and crude polysaccharides from Agave sisalana boles by an in vitro screening. Crude polysaccharides were obtained from the aqueous bole extract by precipitation with acetone and resuspension in water. The liquid extract and the polysaccharide solution were then spray dried and submitted to thermal analysis and quantification of metabolites. Prebiotic activity was checked on probiotic strains belonging to the Lactobacillus genus using inulin, fructo-oligosaccharides, fructose and glucose as positive controls. The powder of A. sisalana bole extract, which has recently been identified as a rich source of inulin, exhibited higher potential of fermentation compared with crude polysaccharides. 相似文献
993.
BoRa Lee Anthony C. Willis Jas S. Ward Warren T. Smith Ping Lan Martin G. Banwell 《化学:亚洲杂志》2020,15(19):3059-3081
Syntheses of a range of chemically well‐defined oligopyrrole/benzenoid hybrids are described using tandem Suzuki‐Miyaura cross‐coupling/bromo‐desilyation reaction sequences for linking borylated pyrroles, halogenated pyrroles and/or dibromobenzenes to one another. By such means, including iterative variants, a range of all α‐linked, all β‐linked oligopyrroles as well as certain combinations thereof have been assembled, some of them for the first time. The conductivities of iodine‐treated thin films formed from certain such systems have been determined. 相似文献
994.
Josef Bartos Marta Klimov 《Journal of polymer science. Part A, Polymer chemistry》1996,34(9):1741-1746
For a series of five amorphous polymers with a broad range of Tg values the kinetics of macroradical decay was measured by ESR technique and evaluated by the second-order kinetic model. It was found that the temperature Ttr of the transition between two regions of different reactivity in free radical decay reaction agrees quite well with the temperature parameter T0 of the Vogel-Fulcher-Tamman-Hesse (VFTH) equation for α-segmental dynamics. This parameter represents the onset of α-segmental mobility in glassy state below Tg. A nontraditional way of the estimation of T0 values for α-segmental dynamics through study of the macroradical decay in glassy state of amorphous polymers has been suggested. © 1996 John Wiley & Sons, Inc. 相似文献
995.
996.
Michel Martin 《Journal of separation science》1996,19(12):709-709
997.
Martin E. R. Shanahan 《Macromolecular Symposia》1996,101(1):463-470
Classic theory predicts a unique value of equilibrium contact angle, θo, for a given solid/liquid/fluid system. However, wetting phenomena are often very complicated in practice, with contact angle hysteresis being a major source of problems in interpretation. Contact angle variability is related to several factors, but we consider two which are particularly relevant to polymeric substrates - effects of orientation of molecular chains near the surface and local solid strain at the wetting front. A model is proposed to explain “stick-slip” motion of the triple line. 相似文献
998.
999.