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1.
Pól J Varadová Ostrá E Karásek P Roth M Benesová K Kotlaríková P Cáslavský J 《Analytical and bioanalytical chemistry》2007,388(8):1847-1857
Pressurised fluid extraction using water or methanol was employed for the extraction of stevioside from Stevia rebaudiana Bertoni. The extraction method was optimised in terms of temperature and duration of the static or the dynamic step. Extracts
were analysed by liquid chromatography followed by UV and mass-spectrometric (MS) detections. Thermal degradation of stevioside
was the same in both solvents within the range 70–160 °C. Methanol showed better extraction ability for isolation of stevioside
from Stevia rebaudiana leaves than water within the range 110–160 °C. However, water represents the green alternative to methanol. The limit of
detection of stevioside in the extract analysed was 30 ng for UV detection and 2 ng for MS detection. 相似文献
2.
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
3.
Li Wang Shuguang Jian Peng Nan Jimei Liu Yang Zhong 《Chemistry of Natural Compounds》2005,41(5):491-493
The chemical constituents of leaf oils of Elephantopus scaber L. from 12 locations in Southern China, including three provinces and Hong Kong, were investigated using GC/MS. A total of
24 compounds were detected, of which 20 were identified by their mass spectra fragmentation patterns. The major compounds
include hexadecanoic acid (8.19–39.22%), octadecadienoic acid (trace - 29.22%), five alkane homologues, i.e., n-tetradecane
(1.19–5.26%), n-pentadecane (3.22–12.05%), n-hexadecane (2.38–16.26%), n-heptadecane (2.48–15.32%), and n-octadecane (1.39–9.59%),
as well as tetramethylhexadecenol (2.06–4.31%). Hierarchical cluster analysis classified the leaf oils into two groups. Two
main chemotypes of leaf oils in E. scaber were thus identified, one rich in hexadecanoic acid and octadecadienoic acid, and the other rich in the five alkane homologues.
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Published in Kimiya Prirodnikh Soedinenii No. 5, pp. 403–404, September–October, 2005. 相似文献
4.
Aerial parts of Sideritis cilicica Boiss. & Bal. and Sideritis bilgerana P.H. Davis (Lamiaceae) were hydrodistilled to obtain essential oils that were then analyzed by GC and GC/MS. β-Pinene (39%),
α-pinene (28%), and β-phellandrene (20%) were the main components in the oil of S. cilicica, while β-pinene (48%), and α-pinene (32%) were the major constituents in the oil of S. bilgerana. The antimicrobial activities of the oils were evaluated by using the microdilution broth method. Both of the oils showed
good inhibitory effects on C. albicans.
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Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 559–561, November–December, 2005. 相似文献
5.
A new compound of formula C28H48O with mp 179-180°C (aqueous ethanol) that was called eucanbin was isolated pure by column chromatography of the ethanol extract
of the aerial part of Eupatorium cannabinum L. The structure 24α-methylcholest-20(21)-en-3β-ol was assigned based on chemical and spectral data.
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–320, May–June, 2009. 相似文献
6.
Galactomannans with galactose:mannose ratios 1:1.48 and 1:1.33, [α]D +67.9 and +76.4°, [η] 870.3 and 1337.1 mL/g, and molecular weights 999 and 1549 kDa, respectively, were isolated in 0.59
and 4.65% yields (of seed mass) from seeds of Astragalus alpinus and A. tibetanus (Fabaceae). Physicochemical methods (CrO3 oxidation; methylation–GC/MS; IR, NMR, and 13C spectroscopy) found that the main polysaccharide chain consisted of 1,4-β-D-mannopyranose units substituted 67.5% (A. alpinus) and 75.2% (A. tibetanus) at the C-6 position by single α -D-galactopyranose units. The contents of mannobiose blocks Man–Man, (Gal)Man–Man/Man–Man(Gal), and (Gal)Man–Man(Gal) variously
substituted with galactose were according to 13C NMR spectroscopy 15.9, 55.5, and 28.6% in A. alpinus galactomannan and 9.9, 42.3, and 47.8% in A. tibetanus galactomannan. 相似文献
7.
G. Ozek T. Ozek K. H. C. Baser E. Hamzaoglu A. Duran 《Chemistry of Natural Compounds》2007,43(6):667-671
The component composition of essential oils produced by steam distillation from flower heads, leaves, and stems of Salvia anatolica (Lamiaceae), a recently described new species endemic from Turkey, was studied by GC/FID and GC/MS. A total of 127 volatile
components representing 96% of the oil was identified in essential oil from flower heads and leaves. It was found that the
principal oil components of flower heads and leaves were α-pinene (10.9%), β-pinene (6.7%), α-copaene (6.3%), heptacosane (6.2%), and hexadecanoic acid (5.0%). A total of 109 volatile compounds representing 87.9% of
the oil was characterized in essential oil isolated from stems. The principal oil components of stems were identified as hexadecanoic
acid (27.2%), tetradecanoic acid (15.2%), dodecanoic acid (5.5%), and α-copaene (5.0%).
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Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 552–555, November–December, 2007. 相似文献
8.
Characterization of Thermo-stable Endoinulinase from a New Strain <Emphasis Type="Italic">Bacillus Smithii</Emphasis> T7 总被引:1,自引:0,他引:1
A new thermophilic inulinase-producing strain, which grows optimally at 60 °C, was isolated from soil samples with medium
containing inulin as a sole carbon source. It was identified as a Bacillus smithii by analysis of 16s rDNA. Maximum inulinase yield of 135.2 IU/ml was achieved with medium pH7.0, containing inulin 2.0%, (NH4)H2PO4 0.5%, yeast extract 0.5%, at 50 °C 200 rpm shaker for 72-h incubation. The purified inulinase from the extracellular extract
of B. smithii T7 shows endoinulinolytic activity. The optimum pH for this endoinulinase is 4.5 and stable at pH range of 4.0–8.0. The optimum
temperature for enzyme activity was 70 °C, the half life of the endoinulinase is 9 h and 2.5 h at 70 °C and 80 °C respectively.
Comparatively lower Michaelis–Menten constant (4.17 mM) and higher maximum reaction velocity (833 IU/mg protein) demonstrate
the endoinulinase’s greater affinity for inulin substrate. These findings are significant for its potential industrial application. 相似文献
9.
E. D. Khairitdinova E. M. Tsyrlina L. V. Spirikhin N. I. Fedorov M. S. Yunusov 《Chemistry of Natural Compounds》2005,41(5):575-577
The known alkaloids deltaline, methyllycaconitine, elasine, and the new norditerpene alkaloid alpinine were isolated from
the aerial part of Delphinium alpinum. The structure of the last was proposed as 1α,6β, 16β-trimethoxy-7-hydroxy-8-ethoxy-14α-propionyloxy-4β-(2″-methyl)succinylanthranoyloxymethyl-N-ethylaconitane
on the basis of PMR, 13C NMR, IR, and mass spectra.
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Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 469–471, September–October, 2005. 相似文献
10.
T. V. Kharlamova 《Chemistry of Natural Compounds》2007,43(4):391-394
The alkylation of 1,6,8-trihydroxy-3-methylanthraquinone (frangula-emodin) by α-bromoalkylmethylketones was investigated. Hydroxyls in the 1-and 8-positions of the β-derivatives were O-acylated. The compositions and structures of the prepared compounds were confirmed by elemental analysis and UV, IR, PMR,
and 13C NMR spectroscopy.
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Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 324–326, July–August, 2007. 相似文献
11.
Jian Zhang Zhi-Qi Yin Peng Cao You-Bin Li Jin-Ao Duan 《Chemistry of Natural Compounds》2008,44(6):701-703
A new flavonol derivative 3, 8-dihydroxy-10-methoxy-5-H-isochromeno[4, 3-b]chromen-7-one (1) together with four known compounds, glutinone (2), luteolin (3), acacetin 7-O-α-L-rhamnopyranosyl- (1→6)-β-D-glucopyranoside (4), and rutin (5) were isolated from the dried roots of Fagopyrum dibotrys. Their structures were determined by UV, IR, MS, 1H, and 13C NMR spectroscopic analysis, including 2D NMR.
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 567–568, November–December, 2008. 相似文献
12.
Peng Ping Wenshou Wang Peibiao Zhang Xuesi Chen Xiabin Jing 《Frontiers of Chemistry in China》2007,2(4):331-336
A series of segmented poly(L-lactide)-polyurethanes (PLA-PUs) were synthesized by a two-step method, with oligo-poly(L-lactide) (PLA) as the soft segments and the reaction product of 2,4-toluene diisocyanate (TDI) and ethylene glycol (EG) as
the hard segments. The shape-memory properties and biocompatibility of PLA-PUs were examined. The 50% compressed PLA-PUs could
recover almost 100% to their original shape within 10°C from the lowest recovery temperature (22°C–37°C). In the recovery
process the PLA-PU showed a maximum contracting stress in the range of 1.5–4 MPa. Cell incubation experiments show that PLA-PU
has biocompatibility comparable to that of pure PLA. Therefore, this kind of polyurethane can be used for implanted medical
devices with shape memory requirements.
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Translated from Chemical Journal of Chinese Universities, 2007, 28(2): 371–375 [译自: 高等学校化学学报] 相似文献
13.
A. S. Volk I. N. Krasikova S. D. Anastyuk P. S. Dmitrenok T. F. Solov’eva 《Chemistry of Natural Compounds》2007,43(5):519-524
The structure of lipid A from the marine γ-proteobacterium Pseudoalteromonas nigrifaciens IAM 13010T that was prepared by hydrolysis of the corresponding lipopolysaccharide by acetic acid (1%) was determined by chemical analysis,
13C NMR spectroscopy, and MALDI/TOF and LSIMS mass spectrometry. It was shown that lipid A is a β-1,6-bonded disaccharide of glucosamine that is substituted by two phosphoric acids (in the C1 and C4′ positions), two (R)-3-hydroxyalkanoic
(normal and branched) acids with ester bonding (at the C3 and C3′-positions), and (R)-3-hydroxydodecanoic and (R)-3-dodecanoyloxydodecanoic
acids (both with amide bonding at C2′ and C2, respectively). It was hypothesized that this type of structure is typical of
lipid A from bacteria of the genus Pseudoalteromonas in general.
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Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 425–429, September–October, 2007. 相似文献
14.
Microwave-assisted condensation of benzaldehyde (3a,b) with acetone in aqueous sodium hydroxide adsorbed on basic alumina provides phenylbutenone (4a–4b) in 68–71% yield within 4 min, which upon further reduction with sodium borohydride and basic alumina gives phenylbutenol
(5a,b) in 91–94% yield within 2 min. Dehydration of 5 with anhydrous copper (II) sulfate gives phenylbutadiene (1a,b), a metabolite of Zingiber cassumunar, within 3 min in 42–48% yield, respectively. All the steps involve environmental friendly solvents and reagents, mild reaction
conditions, and overall formation of product 1a,b from 3a,b in 34–38% yield within 9 min under microwave irradiation.
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Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 300–302, July–August, 2005. 相似文献
15.
N-tert-Butoxycarbonyl-7-and N-tert-butoxycarbonyl-8-bromo-10-azabicyclo[4.3.1]deca-3,7-dienes are convenient substrates for further modification using replacement
of the Br atom by a cyano group or a Li atom. Treatment of lithium derivatives with dimethylformamide and N-methoxy-N-methylacetamide gave the corresponding α,β-unsaturated aldehydes (67–84%) and ketones (∼70%). Ketone 4b is a direct precursor of a homolog of the alkaloid ferruginine.
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1794–1796, September, 2007. 相似文献
16.
A new xanthone (1, 1,7-dihydroxy-2-methoxyxanthone), in addition to the known metabolites 1,7-dihydroxyxanthone (2), 24(R)-stigmast-7,22 (E)-dien-3α-ol (3), and 1,7-dimethoxyxanthone (4), was isolated from the roots of Securidaca inappendiculata. Compounds 1–4 were evaluated by anti-HIV assay and 1–3 showed anti-HIV-1inhibitory activity in vitro.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 348–349, July–August, 2008. 相似文献
17.
Hydrodistilled volatile oils from crushed dry stems, leaves, and roots of Prangos latiloba Korov. (Umbelliferae) growing wild in Sabzevar (Iran) were analyzed by GC and GC/MS. Eight compounds constituting 84.72% of stem oil, twelve compounds
constituting 95.39% of leaf oil, and nine compounds constituting 88.73% of root oil have been identified. The main components
of stem oil were γ-cadinene (30.39%), α-pinene (25.47%), and sabinene (12.55%). The main components of leaf oil were germacrene
D (27.79%), α-pinene (17.81%), β-caryophyllene (12.75%), and β-pinene (11.23%). The main components of root oil were spathulenol
(29.5%), 1,8-cineol (19.42%), p-cymene (17.03%), and α-bisabolol (15.33%).
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Published in Kimiya Prirodnikh Soedinenii, No. 5, pp. 443–444, September–October, 2005. 相似文献
18.
E. D. Khairitdinova E. M. Tsyrlina L. V. Spirikhin N. I. Fedorov M. S. Yunusov 《Chemistry of Natural Compounds》2005,41(5):572-574
A mixture of two new norditerpene alkaloids consisting of two regioisomers was isolated from the total alkaloids of Delphinium cuneatum roots. Their structures were proposed as 16-demethoxydelavaine (2a and b) on the basis of PMR, 13C NMR, IR, and mass spectra.
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Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 467–468, September–October, 2005. 相似文献
19.
The essential oil of Nepeta involucrata (Bunge) Bornm. (Lamiaceae) obtained by hydrodistillation from the aerial parts during the flowering stage was analyzed by
GC and GC-MS. Forty-eight compounds representing 97.2% of total oil were identified. The main compounds of the oil were 1,8-cineol
(23.1%), germacrene-D (15.1%), and β-pinene (12.2%). No traces of nepetalactone isomers were found as oil constituents.
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Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 562–564, November–December, 2005. 相似文献
20.
The composition of the lipophilic extract from the two specimen of the sponge Axinella carteri (Dendy) collected from two different depths of the Bay of Bengal of the Orissa coast were investigated. Fatty acids, as well
as volatile compounds and sterols, were identified. A high concentration of polyunsaturated fatty acids was identified from
depth species compared to the species collected from shallow water. The presence of a high concentration of a polymethyl-branched
fatty acid, i.e., phytanic acid, and a demospongic acid (C26:2, Δ 5,9) were identified in both specimen, but the % composition
of both acids were more in the species collected from depth than the species collected from shallow water. Important polyunsaturated
fatty acids like 5,8,11,14-eicosatetraenoic acid and 5,8,11,14,17-eicosapentaenoic acid (EPA) were also found in depth species
which were absent in the species collected from shallow water. Antimicrobial screening of the lipid extracts of A. carteri was also studied against different pathogens.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 224–227, May–June, 2008. 相似文献