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1.
D. T. Asilbekova F. M. Tursunkhodzhaeva A. M. Nigmatullaev 《Chemistry of Natural Compounds》2009,45(3):322-324
The composition of lipids from the aerial parts of two species of halophytes from the family Chenopodiaceae, Halostachys caspica C. A. Mey. and Halocharis hispida Bge. was determined. Neutral lipids (NL, 62.1 and 54.2%, respectively) dominated the total lipids (TL) of these plants. More
than a third of the NL were esters of aliphatic alcohols and phytosterols (FAE). Fatty acids 16:0, 18:1, and 18:2 dominated
the acids of FAE; 16:0, 18:1, and 18:3, the phospholipids. The principal fatty acids of glycolipids were unsaturated acids
(68.3 and 75.1%) with linolenic acid dominating (44.9 and 43.5%).
Presented at the 7th International Symposium on the Chemistry of Natural Compounds, Tashkent, October 16–18, 2007.
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 276–278, May–June, 2009. 相似文献
2.
Chen Dong Guolin Li Zhuoqi Li Honglin Zhu Mingquan Zhou Zhongli Hu 《Applied biochemistry and biotechnology》2009,158(3):605-614
A rapid amplification cDNA end (RACE) assay was established to achieve the complete sequence of mitochondrial manganese-superoxide
dismutase (Mn-SOD) cDNA in Nelumbo nucifera. The obtained full-length cDNA of Mn-SOD was 926 bp and contained a 699-bp open reading frame encoding an Mn-SOD precursor of 233 amino acids. The recombinant of
Mn-SOD expressed by PET-32a vector in Escherichia coli BL21 was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blotting assays. A 3D structural
model of the Mn-SOD was constructed by homology modeling. Real-time polymerase chain reaction analysis revealed that Mn-SOD mRNA was expressed in young leaves, blossom, stems, and terminal buds during reproductive stage but with the highest expression
in young leaves. This significant difference demonstrated the differential expression of Mn-SOD in various organs of N. nucifera. 相似文献
3.
N. U. Mirzaeva T. V. Chernenko S. D. Gusakova Sh. Sh. Sagdullaev 《Chemistry of Natural Compounds》2011,47(3):355-357
Lipids from the air-dried aerial part (AP) and seeds of Silybum marianum (L.) Gaerth. (Asteraceae) were studied. The class and fatty acid compositions of neutral lipids (AP, seeds) and glyco- and
phospholipids (AP) were determined. Neutral lipids (NL) with a complicated set of lipophilic components, mainly triterpenols,
sterols, and their esters predominated in the AP. The fatty acids of the AP were dominated by 16:0, 18:2 (glycolipids), and
18:3 (neutral lipids, phospholipids); of seed NL, by 18:2 and 18:1. The content and composition of flavolignans isolated from
defatted seeds and the content of total protein in the meal were found. 相似文献
4.
T. F. Ibragimov M. G. Levkovich V. A. Saprykina Kh. M. Shakhidoyatov 《Chemistry of Natural Compounds》2010,46(5):767-770
N-Chloroacetylcytisine was synthesized by acylation of (–)-cytisine. Stable Z- and E-conformers with respect to rotational isomerism around the N-12–CO bond were found in PMR spectra at room temperature. The
point at which PMR resonances of the Z- and E-conformers coalesced upon heating was measured. The transition barrier between the conformers was estimated. 相似文献
5.
A. V. Lezov G. E. Polushina A. A. Lezov P. S. Vlasov N. S. Domnina 《Polymer Science Series A》2011,53(2):93-101
The hydrodynamic and conformational properties of molecules of poly(N,N-diallyl-N,N-dimethylammonium chloride) and N,N-diallyl-N,N-dimethylammonium chloride-maleic acid copolymers of different compositions in solutions with various ionic-strength and pH
values, as well as of the polyelectrolyte complex based on the copolymer with dodecyl sulfate anions in chloroform, are studied.
For poly(N,N-diallyl-N,N-dimethylammonium chloride) molecules in a 1 M NaCl solution, the Kuhn segment length and the hydrodynamic diameter of the
chain are estimated as A = 3.9 nm and d = 0.48 nm, respectively. In acidic solutions with pH 3.5, the copolymers demonstrate behavior typical for polyelectrolytes.
In an alkaline solution with pH 13, when 1 M NaCl is added to the solution of the copolymer containing 29 mol % maleic acid
units, there is an antipolyelectrolyte effect that manifests itself as an increase in the intrinsic viscosity of the copolymer
and in the hydrodynamic radius of its molecules. It is found that an increase in the fraction of maleic acid units in the
copolymer from 12 to 42 mol % brings about a reduction in the equilibrium rigidity of its macromolecules from 4.1 to 2.2 nm.
The equilibrium rigidity of polyelectrolyte-complex molecules is higher than that of initial copolymer molecules owing to
steric interactions arising between the aliphatic chains of dodecyl sulfate anions. In an electric field, the molecules of
the complex are oriented owing to the induced dipole moment resulting from the displacement of dodecyl sulfate anions along
the chain contour. 相似文献
6.
S. Petrovic S. Sobajic S. Rakic A. Tomic J. Kukic 《Chemistry of Natural Compounds》2004,40(5):420-422
The kernel oils of Quercus robur and Quercus cerris were obtained by Soxhlet extraction using petroleum ether. Oil yields were found to be 5.2–5.6% and 4.3–4.8% for Q. robur and Q. cerris kernel, respectively (expressed in g per 100 g of dried plant material). The physical and chemical constants, unsaponifiable matter and total fatty acids were determined. The total fatty acid composition of oils was determined by GC in the methyl ester form. Considering the composition and content of fatty acids, the examined kernel oils were very similar. Seven fatty acid components were identified in both oils: palmitic, stearic, arachidic, palmitoleic, oleic, linoleic, and -linolenic. In Q. robur and Q. cerris kernel oils the principal acids were oleic (44.3% and 43.0%, respectively) and linoleic (37.2% and 32.6%, respectively), followed by a significant amount of palmitic acid.Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 347–348, September–October, 2004. 相似文献
7.
A new flavonoid, kaempferol-3,4′-di-O-α-L-rhamnopyranoside (1), and three known flavonoids (2–4) were isolated from the aerial parts of T. communis L. The structure of the new compound was elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed significant antioxidant activity (IC50 187.151 ± 0.821 μM, and 92.079±0.513 μM, respectively), whereas compounds 3 and 4 showed moderate activity in DPPH free radical scavenging assays.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 295–297, May–June, 2009. 相似文献
8.
Summary. Oral L-carnitine supplementation is frequently reported to have beneficial effects on exercise capacity in clinical populations and has been considered as a potential ergogenic aid for endurance athletes. However, this latter view is largely unsubstantiated possibly due to many experimental studies being poorly controlled or difficult to compare. The potential for oral L-carnitine supplementation to influence skeletal muscle carnitine content has been questioned and there are several key factors identified that may explain variations between study outcomes. Recent more well controlled research suggests some potential for L-carnitine to act as a key regulator of cellular stress, possibly through an impact on the integration of carbohydrate and lipid metabolism, and this work should be followed up in future by well controlled studies in both athlete and clinical subject groups. 相似文献
9.
Thermal investigations were performed on a colony of the Colombian stingless bee Trigona (Frieseomelitta) nigra paupera by means of thermometry and direct calorimetry.
A nest with about 2000 individuals was transferred to a twin calorimeter, where the bees continued their normal life and development.
Two camping boxes (‘Poor Man’s Calorimeter, PMC’) with Peltier elements as cooling systems were used as a differential system.
Each box had a volume of 8 L and a sensitivity of 19.2 mV W−1. The colony was monitored calorimetrically and thermometrically with resistors distributed in the nest. Signals were recorded
continuously by a four-channel data logger. 相似文献
10.
Summary. A new synthetic route was developed for the preparation of trans-3-hydroxy-16,17-seco-pregna-5,17(20)-dien-16-al, using Grob fragmentation as the key step. This seco-steroid contains a formyl group and an unsaturated side-chain in a sterically favourable position, and is therefore a promising starting material for the synthesis of novel condensed steroid heterocycles.Received March 22, 2003; accepted April 22, 2003
Published online September 25, 2003 相似文献
11.
In neutral zinc the 4p
2 configuration lies above the 3d
104s ionization limit and its levels become perturbers in the continuum. Lines have been identified in the Zn I spectrum for the
multiplet, whereas no lines have been found for transitions to 4p
2 1
D or 1
S. In this paper, cross sections for photoionization from 4s4p levels are reported that reveal the positions and widths of the 4p
2 resonances. Calculations were performed using the multiconfiguration Hartree-Fock (MCHF) and B-spline R-matrix (BSR) method. Results from Breit–Pauli calculations that ignore the background continua are also presented. Included
in the latter are energies for the levels and transition data (transition energies, line strengths, f-values, and A-rates) for all E1 transitions between these
levels. Transition energies and the agreement in the length and velocity values, particularly for allowed transitions, indicate
the accuracy of the computational model. Line widths are compared with other estimates.
Contribution to the Serafin Fraga Memorial Issue. 相似文献
12.
Chen N Huang J Feng ZB Yu L Xu QY Wen TY 《Applied biochemistry and biotechnology》2009,158(3):595-604
In this study, the fed-batch fermentation technique was applied to improve the yield of l-threonine produced by Escherichia coli TRFC. Various fermentation substrates and conditions were investigated to identify the optimal carbon source, its concentration
and C/N ratio in the production of l-threonine. Sucrose was found to be the optimal initial carbon source and its optimal concentration was determined to be 70 g/L
based on the results of fermentations conducted in a 5-L jar fermentor using a series of fed-batch cultures of E. coli TRFC. The effects of glucose concentration and three different feeding methods on the production of l-threonine were also investigated in this work. Our results showed that the production of l-threonine by E. coli was enhanced when glucose concentration varied between 5 and 20 g/L with DO-control pulse fed-batch method. Furthermore,
the C/N ratio was a more predominant factor than nitrogen concentration for l-threonine overproduction and the optimal ratio of ammonium sulfate to sucrose (g/g) was 30. Under the optimal conditions, a final l-threonine concentration of 118 g/L was achieved after 38 h with the productivity of 3.1 g/L/h (46% conversion ratio from
glucose to threonine). 相似文献
13.
U. S. Makhmudov Sh. B. Rakhimov B. Tashkhodzhaev M. G. Levkovich V. I. Vinogradova 《Chemistry of Natural Compounds》2008,44(2):208-212
The molecular structures of N-(o-and p-hydroxybenzyl)cytisine were investigated by NMR spectroscopy, x-ray structure analysis, and molecular modeling. It was found
that NMR resonances of the OH and aromatic protons in N-(o-hydroxybenzyl)cytisine were doubled because of the presence of two conformers in solution.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 165–168, March–April, 2008. 相似文献
14.
Analysis of cellulose biosynthesis using molecular approaches has been successful in identifying genes in many cellulose-producing
organisms, yet the mechanism of cellulose biosynthesis still remains to be understood. We are interested in developing the
moss Physcomitrella patens as a useful system for the study of cellulose biosynthesis. This moss affords a number of advantages including a haploid
dominated gametophyte and a very high efficiency of homologous recombination in its nuclear DNA for constructing gene knockouts.
In addition, P. patens has only a primary cell wall unlike Arabidopsis thaliana, which has both a primary and a secondary cell wall. We identified two full-length cellulose synthase (CesA) genes of P. patens, PpCesA6 and PpCesA7 from an EST database and have analyzed the genomic sequences. PpCesA6 and PpCesA7 show high similarity to each other, both at the cDNA and genomic DNA levels. Single and double knockouts of PpCesA6 and PpCesA7 were generated and screened for phenotypic changes. While the PpCesA6 and PpCesA7 single knockouts did not show any obvious phenotypic differences from the wild-type, the double knockout had significantly
reduced stem length. These results suggest that PpCesA6 and PpCesA7 probably have a very similar role in cellulose biosynthesis and their functions may be redundant. Additionally, their roles
may overlap with the other P. patens CesAs as observed for CesAs involved in primary cell wall biosynthesis in A. thaliana. 相似文献
15.
Xu Feng Dong Jiang Yu Shan Tingbo Dai Yunfa Dong Weixing Cao 《Chemistry of Natural Compounds》2008,44(2):171-173
Two new flavonoid-C-glycosides named triticuside A (1a) and triticuside B (1b) were isolated from bran of Triticum aestivum L. The structures of the two new compounds were elucidated by spectral techniques including 1H NMR, 13C NMR as well as HSQC, HMBC, and COSY.
Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 135–137, March–April, 2008. 相似文献
16.
Mohammad M. Fares Adeeb S. El-faqeeh Hasan Ghanem Mohammad E. Osman Elfatih A. Hassan 《Journal of Thermal Analysis and Calorimetry》2010,99(2):659-666
The synthesis, characterization, and hydrogel properties of starch-g-(tert-butylacrylate) and starch-g-(n-butylacrylate) copolymers were studied. The optimum conditions for the grafting process of tert-butylacrylate into 1.0 g of starch were as follows: [tert-butylacrylate] = 0.04 mol/L, [CAN] = 9.0 × 10−4 mol/L, temperature = 20 °C in 100 mL solution, whereas the results using n-butylacrylate monomer were as follows: [n-butylacrylate] = 0.04 mol/L, [CAN] = 4.0 × 10−3 mol/L, temperature = 30 °C in 100 mL solution. The grafting evidences of monomers into starch were done through TG and its
derivative DTG for thermal changes and mass losses, scanning electron microscope (SEM) for morphological changes, powder X-ray
for crystallinity measurements and FTIR for functional group changes. Acid hydrolysis method was used efficiently to allow
the calculations of the viscosity average molecular weight (M
v) of the grafted chains on starch and consequently the real percent of grafting efficiency (i.e. %GY). The capability of starch-g-(n-BAC) hydrogel to absorb water were found 10 times more than starch-g-(tert-BAC) hydrogel, which were clarified through the X-ray and SEM results. 相似文献
17.
The lipid composition of Potamogeton pectinatus L. collected in different parts of the Sok River in the Lower Volga basin was studied. Differences were found in the quantitative
lipid composition of the plant as a function of habitat. Plants inhabiting contaminated waters typically had a lower content
of total lipids and glycolipids with an increased content of neutral lipids in addition to a lower content of polyunsaturated
acids. 相似文献
18.
Mei-Liang Zhou Xue-Mei Zhu Ji-Rong Shao Yan-Min Wu Yi-Xiong Tang 《Applied biochemistry and biotechnology》2012,166(7):1674-1684
Catharanthus roseus (L.) G. Don is a plant species known for its production of a variety of terpenoid indole alkaloids, many of which have pharmacological
activities. Catharanthine can be chemically coupled to the abundant leaf alkaloid vindoline to form the valuable anticancer
drug vinblastine. To study and extract catharanthine and other metabolites from C. roseus, a technique was developed for producing hairy root cultures. In this study, the Agrobacterium rhizogenes A4 was induced in the hairy roots from leaf explants, and the concentration of antibiotics (100 mg/L kanamycin) was elucidated
for selection after transformation. The polymerase chain reaction amplification of rol genes results revealed that transgenic hairy roots contained rol genes from the root induced (Ri)-plasmid. Catharanthine from C. roseus hairy roots was separated and analyzed using high-performance liquid chromatography. Over-expression of CrOrca3 (octadecanoid-responsive Catharanthus AP2/ERF domain), and cytohistochemical staining methods were used to validate transgenic
hairy roots from C. roseus. Hairy root culture of C. roseus is a valuable approach for future efforts in the metabolic engineering of terpenoid indole alkaloids in plants. 相似文献
19.
Yu Chen Xu Feng Xiaodong Jia Ming Wang Jinyu Liang Yunfa Dong 《Chemistry of Natural Compounds》2008,44(1):39-43
The structures of seven triterpene glycosides (1–7), of which the 23-O-acetyl, 28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin 3-O-β-D-glucopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside (2) was new, from the flower buds of Lonicera macranthoides were established using chemical and NMR spectroscopic methods.
Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 32–34, January–February, 2008. 相似文献
20.
N. K. Yuldasheva N. T. Ul’chenko N. P. Bekker T. V. Chernenko O. V. Skosyreva A. I. Glushenkova B. Heuer 《Chemistry of Natural Compounds》2011,46(6):866-868
Lipids from Crambe amabilis Butk. et Majlun and C. kotschyana Boiss. grown in the open in Uzbekistan in soil imported from the Aral Sea region were studied. It was found that the seed
oil content decreased with increasing salinity of irrigation water with EC 1.5 up to 9.0 dS/m. The content of polar lipids
increased. The content of unsaturated acids from C. amabilis neutral lipids was 94.74–97.46%; C. kotschyana, 95.76– 96.78%. 相似文献