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1.
Abstract

The enzymatic reduction of prochiral heterocyclic ketones by carrot (Daucus carota) root in water afforded the corresponding S-alcohols in accordance with the Prelog's rule. The reaction was performed under various conditions in order to optimize the procedure of bioreduction regarding reaction time, yield, and optimal mass of carrot. The optimized procedure was used to test the ability of other plants to carry out the reaction. In the latter experiment, it was observed that, with regard to stereospecificity, most vegetables tested were poorer reducing agents compared to D. carota.  相似文献   
2.
Introduction Carrots,avegetablewithabundantnutrition,are therootsofDaucuscarotaL.var.sativaHoffm[1],whichisanumbelliferaeplant.Carrotsshowanti can cerandanti oxidationactivities.Theycanalsobeused topreventeyediseasesandimproveimmunity[2—11],thefactsareun…  相似文献   
3.
Two new eudesmane-type glucopyranosides have been isolated from the fruits of Daucus carota L. On the basis of their spectroscopic and chemical evidence, the new compounds were elucidated as daucucarotol-10-O-β-d-glucopyranoside (1) and decahydro-7-[(2-O-β-d-glucopyranosyl)-isopropyl]-1β,4aα-dimethyl-(1α,4α,8aβ)-naphthalenetriol (2). Compounds 1 and 2 showed moderate antitumour activity against human ECA-109 and gave IC50 values of 23.22 and 26.76 μM, respectively.  相似文献   
4.
The application of triazole fungicides is a common practice in the cultivation of carrot (Daucus carota L.) plants. It is there for seems important to test the changes that are occurring in this food crop under triazoles, the non-traditional plant growth regulators, treatments in order to identify the extent to which it tolerate the fungicide application and thereby make it an economical food crop. A field experiment was conducted to find out the effects of two triazole fungicides (hexaconazole (HEX) and paclobutrazol (PBZ) at 20 mg l−1 plant−1) on the biomass, yield, electrolyte leakage, lipid peroxidation and antioxidant potential of carrot. The treatments were given to plants on 15, 30 and 45 days after sowing (DAS). The plants were uprooted for analyses of growth and biochemical parameters on 60 DAS. It was found that both HEX and PBZ have significant effects on the growth and biochemical parameters of this plant. Among the triazoles used, PBZ performed best in terms of anthocyanin, protein, amino acid, proline, starch and sugar, contents whereas HEX enhanced carotenoids, fresh weight, dry weight and biomass. There was no significant variation in chlorophyll (‘a’ and ‘b’) contents between the two triazole treated plants, but HEX and PBZ proved best when compared to untreated control plants. HEX and PBZ increased - and β-amylases enzymes activities to a significant level. Out of these two triazoles, PBZ performed best in increasing the starch hydrolyzing enzymes activities. The non-enzymatic antioxidant, reduced glutathione (GSH) and antioxidant enzyme ascorbate peroxidase (APX) were increased under fungicide applications. The data suggests that, the application of triazole fungicides may be a useful tool to increase the tuber quality as well as quantity in carrot plants, apart from their fungicidal properties.  相似文献   
5.
The benzene extract of the aerial part ofDaucus sativusis analyzed. Sterols, aliphatic alcohols and their esters, triterpenes, and isoprenes make up >50%% of the extract mass. Carotenoids, -tocopherol, and other biologically active substances are also observed  相似文献   
6.
Six new sesquiterpene lactone esters, daucoguaianolactones A–F ( 1 – 6 ), and one new sesquiterpene lactone, daucoeudesmanolactone A ( 7 ) were isolated from the leaves and stems of Daucus glaber (Forssk .) Thell ., along with the known sesquiterpene lactones talasins A and B and badkhysin. The structures of 1 – 6 were established on the basis of extensive 1D‐ and 2D‐NMR spectroscopic studies and that of 7 by X‐ray crystallography. Compounds 4, 7 , and talasins A and B showed moderate cytotoxicity against P‐388 leukemia cells.  相似文献   
7.
Two biocidal peptides were isolated from carrot seeds (Daucus carota). Their fungicidal activity toward the pathogenic fungus Verticillium dahliae was investigated. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 167–168, March–April, 2006.  相似文献   
8.
Two new sesquiterpenes, 11‐(acetyloxy)torilolone ( 1 ) and 1β‐hydroxytorilolone ( 2 ) were obtained from the fruits of Daucus carota. Their structures were elucidated on the basis of various spectroscopic analyses and chemical evidence.  相似文献   
9.
In the present work, reversed phase (RP) ultra-high-performance liquid chromatography (UHPLC) coupled to quadrupole-time-of-flight (QTOF) mass spectrometry in tandem has been used for the identification of the main phenolic compounds in the aerial parts of Daucus muricatus. The characterisation of the compounds was carried out taking into account retention time, mass accurate measurements, the generated molecular formulae and fragmentation pattern. These data were contrasted with literature and databases, as well as with those of authentic standards when possible. The proposed method provided tentative identi?cation of 30 phenolic and other polar compounds, including hydroxycinnamic acid derivatives, flavonoids and hydroxybenzoic acid derivatives. As a note, hydroxycinnamic acid derivatives were found to be the most diverse phenolic class of Daucus muricatus.  相似文献   
10.
A series of organochalcogeno acetophenones 3 has been submitted to the action of enzymes from Daucus carota root. Some of the chalcogeno ketones tested afforded the chiral organochalcogeno-α-methylbenzyl alcohols 4 in excellent enantiomeric excesses (>99%), under mild and environmentally friendly conditions. The stereoselectivity of the reduction is in accordance with Prelog’s rule. Enzymatic kinetic resolution as alternative process was used to obtain the chiral ortho-organochalcogeno-α-methylbenzyl alcohols in excellent enantiomeric excess (>99%).  相似文献   
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