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1.
A novel water-soluble polysaccharide, designated Bletilla striata polysaccharide b (BSPb), was isolated from a traditional Chinese medicinal herb, Bletilla striata. The crude polysaccharide was obtained by hot water extraction and purified by ion-exchange chromatography. The molecular weight was 260 kDa as determined by HPGPC (high performance gel permeation chromatography). Monosaccharide analysis showed that BSPb contained glucose and mannose with a molar ratio of 3:1. Methylation and spectroscopic analyses with 1D and 2D NMR spectroscopy showed that the backbone of BSPb is mainly composed of (1  2)-linked α-d-mannopyranose and (1  4)-linked β-d-glucopyranose residues. In this study, BSPb plays an important role in protection against the renal fibrosis effect, which is probably mediated by down-regulated TGF-β RI, TGF-β RII, and α-SMA in vitro.  相似文献   

2.
A water-soluble polysaccharide (CPS-2), isolated from the cultured Cordyceps sinensis, was obtained by hot-water extraction, anion-exchange and gel permeation chromatography. Its structural characteristics were investigated by PMP pre-column derivation, periodate oxidation, methylation analysis, FTIR and NMR spectroscopy. CPS-2 was found to be mostly of α-(1  4)-d-glucose and α-(1  3)-D-mannose, branched with α-(1  4,6)-d-glucose every twelve residues on average. CPS-2 had a molecular weight of 4.39 × 104 Da. The protective effect of CPS-2 on the model of chronic renal failure was established by fulgerizing kidney. The changes in blood urea nitrogen and serum creatinine revealed that CPS-2 could significantly relieve renal failure caused by fulgerizing kidney.  相似文献   

3.
Four new triterpenoids, sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4), along with nineteen known compounds (523) were isolated from Swertia yunnanensis. Based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR, [α]D), the structures of sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4) were elucidated as taraxer-14-ene-3α,6β-diol, oleanolic acid 28-O-β-d-glucopyranosyl-(1  2)-O-β-d-glucopyranoside, 2α,3β-di-hydroxyolean-12-en-28-oic acid 28-O-β-d-glucopyranosyl(1  6)-β-d-glucopyranosyl (1  6)-β-d-glucopyranosyl(1  2)-β-d-glucopyranoside and hederagenin 28-O-β-d-glucopyranosyl(1  6)-β-d-glucopyranosyl(1  6)-β-d-glucopyranosyl(1  2)-β-d-glucopyranoside, respectively. Twenty-two compounds were evaluated for their anti-HBV activities on the HepG 2.2.15 cell line in vitro, of which nine compounds showed potent anti-HBV activities. Compounds 1, 56, 1416 and 19 showed activities against the secretion of HBsAg (IC50 values from 0.10 to 1.76 mM) and HBeAg (IC50 values from 0.04 to 1.41 mM), and compounds 11 and 1316 exhibited significant inhibition on HBV DNA replication (IC50 values from 0.01 to 0.09 mM).  相似文献   

4.
Two new saponins of 20, 26-epoxy derivatives of pseudojujubogenin, hoduloside XI (1) and hoduloside XII (2) were isolated from the seeds of Hovenia trichocarpa. The structures of the new compounds were established by extensive NMR experiments and chemical methods. Hoduloside XI was confirmed to be 3-O-{β-d-glucopyranosyl(1  3)-[β-d-xylopyranosyl(1  2)]-α-l-arabinopyranosyl}-20, 26-epoxypseudojujubogenin. Hoduloside XII was identified as 3-O-{β-d-xylopyranose(1  2)glucopyranosyl(1  3)[rhamnopyranose(1  2)]β-d-glucopyranosyl}-20, 26-epoxypseudojujubogenin. The in vitro cytotoxic activity of compounds 1 and 2 was assayed. They displayed inhibitive activities against human cancer cell lines HL60 and K562.  相似文献   

5.
The present study aimed at investigating the structural features and antioxidant activities of a polysaccharide fraction (DHP1A) obtained from Dendrobium huoshanense, a precious herb medicine in China. DHP1A mainly consisted of mannose (Man), glucose (Glc) and a trace of galactose (Gal), with a molecular weight of 6700 Da. Its backbone contained (1  4)-linked α-D-Glcp, (1  6)-linked α-D-Glcp and (1  4)-linked β-D-Manp, with a branch of terminal β-D-Galp. The in vitro antioxidant evaluation revealed that DHP1A had a remarkable inhibition effect on the FeCl2-induced lipid peroxidation. Furthermore, DHP1A pretreatment decreased the production of malondialdehyde (MDA), and restored the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), as well as the level of glutathione (GSH) in the livers of CCl4-treated mice. These results suggested that DHP1A was a potential antioxidant component in D. huoshanense.  相似文献   

6.
Four new oleanane type triterpenoid saponins (1–4) and three known saponins (5–7) were isolated from the whole plant of Clematis lasiandra Maxim. The structures of the four new compounds were elucidated as 3-O-β-d-ribopyranosyl-(1  3)-α-l-rhamnopyranosyl-(1  2)-[β-d-glucopyranosyl-(1  4)]-β-d-xylopyranosyl hederagenin (1), 3-O-β-d-ribopyranosyl-(1  3)-α-l-rhamnopyranosyl-(1  2)-β-d-xylopyranosyl oleanolic acid 28-O-β-d-glucopyranosyl ester (2), 3-O-β-d-ribopyranosyl-(1  3)-α-l-rhamnopyranosyl-(1  2)-β-d-xylopyranosyl hederagenin (3) and 3-O-β-d-ribopyranosyl-(1  3)-α-l-rhamnopyranosyl-(1  2)-[β-d-glucopyranosyl-(1  4)]-α-l-arabinopyranosyl hederagenin (4) on the basis of extensive spectroscopic analysis and chemical evidence. Compounds 1–7 were evaluated for their cytotoxicity against human tumor cell lines HL-60, Hep-G2 and SGC-7901, and all of the evaluated saponins showed significant cytotoxicity to those three tumor cell lines with IC50 in the range from 1.40 to 19.50 μmol/L except for compounds 2 and 6.  相似文献   

7.
A water-soluble polysaccharide LT1 was isolated from the basidiocarps of Lentinus edodes by hot water extraction and ethanol precipitations, further purified by gel chromatography. The Mw of LT1 was estimated to be 642 kDa by using HPGPC. Chemical and spectroscopic studies illustrated that LT1 has a backbone chain composed of 1 → 4-linked and 1 → 3-linked glucopyranosyl residues and has branches of single glucosyl stubs at C-6 of β-(1 → 4)-linked glucopyranosyl. AFM and Congo-red test revealed that LT1 existed as triple helix chain in 0.10 M NaOH solution or distilled water. Our studies showed that LT1 presented significant antitumor bioactivities on Sarcoma180 solid tumor cell implanted in BALB/c mice, which implies that LT1 could be potentially applied as a natural antitumor drug.  相似文献   

8.
Four steroidal saponins were isolated from the anti-anoxic fraction of the 60% EtOH extract of Selaginella uncinata, including two new compounds, (3β, 7β, 12β, 25R)-spirost-5-ene-3, 7, 12-triol-3-O-α-L-rhamnopyranosyl-(1  2)-O-[α-L-rhamnopyranosyl-(1  4)]-O-β-d-glucopyranoside (1), (2α, 3β, 12β, 25R)-spirost-5-ene-2, 3, 12-triol-3-O-α-L-rhamnopyranosyl-(1  2)-O-[α-L-rhamnopyranosyl-(1  4)]-O-β-d-glucopyranoside (2) and two known compounds, (3β, 12β, 25R)-spirost-5-ene-3,12-diol-3-O-α-L-rhamnopyranosyl-(1  2)-O-[α-L-rhamnopyranosyl-(1  4)]-O-β-d-glucopyranoside, (3), (1α, 3β, 25R)-spirost-5-ene-2-diol-3-O-α-L-rhamnopyranosyl-(1  2)-O-[α-L-rhamnopyranosyl(1  4)]-O-β-d-glucopyranoside (4). The four compounds showed potent protective effect against anoxia in the anoxic PC12 cells assay, among which compounds 1 and 2 were the most active. To our knowledge, this is the first study to report the steroidal saponins in the plant S. uncinata and demonstrate their protective effect against anoxia in PC12 cell assay.  相似文献   

9.
Five new triterpenoid saponins, named as sibiricasaponins A–E (15), were isolated and identified from the aerial parts of Polygala sibirica L., together with nine known triterpenoid saponins (614). The chemical structures of the five new triterpenoid saponins (15) were elucidated as 3β,19α-dihydroxyurso-12-ene-23,28-dioic acid 3-O-β-d-glucuronopyranoside (1), pomolic acid 3-O-(3-O-sulfo)-α-l-arabinopyranoside (2), pomolic acid 3-O-(4-O-sulfo)-β-d-xylopyranoside (3), pomolic acid 3-O-(2-O-acetyl-3-O-sulfo)-α-l-arabinopyranoside (4), and 3-O-β-d-glucopyranosyl medicagenic acid 28-O-β-d-galactopyranosyl (1  4)-β-d-xylopyranosyl (1  4)-α-l-rhamnopyranosyl (1  2)-(4-O-acetyl)-[β-d-apiofuranosyl (1  3)]-β-d-fucopyranosyl ester (5), respectively, on the basis of spectroscopic data and physicochemical evidences. These isolated compounds (114) were evaluated for their anti-ischemic effects on oxygen/glucose deprivation (OGD) model in vitro, and only compound 7 showed a weak anti-ischemia effect, with EC50 value of 46.7 μM.  相似文献   

10.
A sensitive, selective, and rapid high performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed for the quantification of rohitukine in rat plasma. HPLC was performed using a Symmetry-Shield C18 (5 μ, 4.6 × 150 mm) column, and isocratic elution with ammonium acetate buffer (pH 4; 10 mM):methanol (08:92, v/v) at a flow rate of 0.6 mL/min. Sample clean-up involved solid phase extraction (SPE) of analyte and internal standard (phenacetin) from 100 μL plasma. The parent  product ion transitions (MRM) for analyte and IS were 306.1  245.1 m/z and 180.1  138.1 m/z respectively, and were monitored on a triple quadrupole mass spectrometer, operating in positive ion mode. The method was validated across the dynamic concentration range of 5–500 ng/mL for rohitukine, with a fast run time of 4.5 min. The analytical method measured concentrations of rohitukine with accuracy (% bias) of <± 10% and precision (% RSD) of <± 12%. Rohitukine was stable during the battery of stability studies viz., bench-top, auto-sampler, freeze/thaw cycles and 30 days of storage in a freezer at − 70 ± 10 °C. Finally, the applicability of this assay has been successfully demonstrated in vivo pharmacokinetic and in vitro metabolism studies in Sprague–Dawley rat. This method will therefore be highly useful for future preclinical and clinical pharmacokinetic studies of rohitukine.  相似文献   

11.
Three new spirostane-type glycosides (13) were isolated from the whole plant of Allium flavum. Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as (20S,25R)-2α-hydroxyspirost-5-en-3β-yl O-β-d-xylopyranosyl-(1  3)-[β-d-galactopyranosyl-(1→2)]-β-d-galactopyranosyl-(1→4)-β-d-galactopyranoside (1), (20S,25R)-2α-hydroxyspirost-5-en-3β-yl O-β-d-xylopyranosyl-(1  3)-[β-d-glucopyranosyl-(1→2)]-β-d-galactopyranosyl-(1→4)-β-d-galactopyranoside (2), and (20S,25R)-spirost-5-en-3β-yl O-α-l-rhamnopyranosyl-(1  4)-[β-d-glucopyranosyl-(1→2)]-β-d-glucopyranoside (3). The three saponins were evaluated for cytotoxicity against a human cancer cell line (colorectal SW480).  相似文献   

12.
Two new trisaccharide intermediates of phenylethanoid glycosides, peiioside A1/A2 (1a/1b) and peiioside B (2), were isolated from the n-BuOH fraction of MeOH extract of the stems of Callicarpa peii H.T. Chang, together with five biogenetic relevant known compounds 37. The structures of compounds 1 and 2 were elucidated by extensive spectroscopic methods (especially 2D-NMR techniques) and acid-catalyzed hydrolysis as O-α-l-rhamnopyranosyl-(1″  3′)-O-[β-d-apiofuranosyl-(1‴  6′)] -4′-O-[(E)-caffeoyl]-d-glucopyranoside] (1a/1b), 3,4-dihydroxy-β-phenylethoxy-O-[β-d-apiofuranosyl-(1‴  6′)-α-l-rhamnopyranosyl-(1″  3′)-O-β-d-glucopyranoside] (2), respectively. On the basis of the isolated compounds, a presumable biogenetic pathway of the biologically interesting phenylethanoid glycosides about forsythoside B (3) and acteoside (4) isolated from this species was proposed. Isolation of five related intermediates (12, 57) provided further support for the biogenetic path. This is the first report about phytochemical research on C. peii and the biogenetic hypothesis of forsythoside B and acteoside.  相似文献   

13.
Two new flavonoids, quercetin-3-O-β-d-xylopyranosyl-(1  2)-α-d-ribopyranoside (1) and kaempferol-3-O-β-d-xylopyranosyl-(1  2)-α-d-ribopyranoside (2), and one new phenolic derivative, gallicin-p-O-(6′-O-caffeoyl)-β-d-glucoside (3), together with twelve known compounds were isolated from the leaves of Rosa sericea (Rosaceae family). The structures of the new compounds were established by means of spectroscopic analysis including one- and two-dimensional NMR spectroscopy. Some of the isolated compounds were tested for the cytotoxicity of a breast cancer cell (MCF-7) line. The results showed that rubanthrone A (4) has moderate cytotoxicity against the MCF-7 cell line.  相似文献   

14.
The antimicrobial activity of lingonberry (Vaccinium vitis-idaea L.) was evaluated against two oral pathogens, Streptococcus mutans and Fusobacterium nucleatum. Long-bed gel permeation chromatography (GPC; Sephadex LH-20) yielded purified flavonoids, with the most efficient minimum inhibitory concentrations (MICs) against planktonic cells in the anthocyanin and procyanidin primary fractions against F. nucleatum (63–125 μg/ml) and in the procyanidin rich fraction against S. mutans (16–31 μg/ml). The purified flavonol glycosides and procyanidins inhibited biofilm formation of S. mutans (MICs 16–31 μg/ml), while the corresponding reference compounds showed no activity. Secondary GPC purification yielded flavonol glycosides devoid of antibiofilm activity in the 50% MeOH fraction, while elution with 70% acetone recovered a brownish material with activity against S. mutans biofilm (MIC 8 μg/ml). Even after HPLC-PDA, NMR, and MALDI-TOF analyses, the structural identity of this material remained unknown, while its color and analytical characteristics appear to be consistent with flavonoid oxidation products.  相似文献   

15.
The fruits of Solanum torvum Swartz, commonly known as Turkey berry, are edible and commonly used as a vegetable in the South Indian population's diet and as an essential ingredient in Thai cuisine. Five new steroidal glycosides together with five known ones were isolated from the fruits of S. torvum Swartz. Based on chemical and spectral evidence, the five new compounds were identified to be 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3β,6α,26-triol-6-O-[α-l-rhamnopyranosyl-(1  3)-O-β-d-quinovopyranoside] (1), 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3-one-6α,26-diol-6-O-[α-l-rhamnopyranosyl-(1  3)-O-β-d-quinovopyranoside] (2), 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3β,6α,26-triol-6-O-β-d-quinovopyranoside (3), 5α-pregn-16-en-20-one-3β,6α-diol-6-O-[α-l-rhamnopyranosyl-(1  3)-β-d-quinovopyranoside] (4), and 5α-pregn-16-en-3,20-dione-6α-ol-6-O-[α-l-rhamnopyranosyl-(1  3)-β-d-quinovopyranoside] (5). These new compounds were assayed for cytotoxicities in vitro, and 1 to 4 showed cyotoxic activity against the human melanoma cell line A375, with IC50 values of 30 μM to 260 μM.  相似文献   

16.
The purpose of this study is to elucidate the bioactive components responsible for the the α-glucosidase inhibitory activity detected in the EtOAc extract of the mushroom Hydnellum concrescens. Two new p-terphenyl derivatives, concrescenins A (1) and B (2), in along with six known compounds thelephantins L (3), I (4), J (5), K (6), dihydroauran-tiacin dibenzoate (7), and curtisian A (8) were isolated from the fruiting bodies of H. concrescens. Their chemical structures were elucidated by NMR experiments. Compounds 14 and 68 showed the inhibitory activity against α-glucosidase with the IC50 of 0.99, 3.11, 4.53, 18.77, 2.98, 5.16, and 8.34 μM, respectively. Kinetic analysis of α-glucosidase indicated that compounds 1 and 2 inhibited the activity of α-glucosidase in a noncompetitive fashion with a Ki value of 0.02 and 0.21 μM, respectively. In antioxidant evaluation, compounds 1 and 4 showed weak DPPH scavenging activity (EC50 = 82.50 and 161.75 μM) and weak reducing ability (EC50 = 193.57 and 152.94 μM). The current research supports the potential use of mushroom-derived p-terphenyl derivatives for the treatment of diabetes.  相似文献   

17.
Five new ursane-type triterpenoidal saponins (15), together with five known ones (610), were isolated from the EtOH extract of the roots of Ilex cornuta. The structures of saponins 15 were elucidated as 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside (1), 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside-6-O-ethyl ester (2), 19α-hydroxyurs-12-en-28-oic acid 3β-O-α-L-arabinopyranosyl-(1  2)-β-D-glucuronopyranoside (3), 3β-O-[α-L-arabinopyranosyl-(1  2)-β-D-glucuronopyranosyl]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (4) and 3β-O-[α-L-arabinopyranosyl-(1  2)-β-D-glucuronopyranoside-6-O-methyl ester]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (5), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and chemical reactions. Protective effects of compounds 110 against H2O2-induced H9c2 cardiomyocyte injury were tested. Compounds 15, 7, and 10 showed cell-protective effects. Among them compound 5 exhibited the highest activity. No significant DPPH radical scavenging activity was observed for compounds 110.  相似文献   

18.
A series of cardiac glycosides were isolated and identified from the anti-tumor fraction of the root of Streptocaulon juventas in previous studies. In the present research, the cytotoxic activities of the 43 cardiac glycosides on three cell lines, human lung A549 adenocarcinoma cell, large cell lung cancer NCI-H460 cell and normal human fetal lung fibroblast MRC-5 cell, were evaluated in vitro. Most of the tested compounds showed potent inhibitory activities toward the three cell lines. Then, the structure–activity relationships were discussed in detail. It was indicated that hydroxyl and acetyl groups at C-16 increased the activity, whereas hydroxyl group at C-1 and C-5 can both increase and decrease the activity. Two glucosyl groups which were connected by C1′  C6′ showed better inhibitory activity against cancer cell lines, while the C1′  C4′ connection showed stronger inhibitory activity against the normal cell line. Also, this is the first report that the activities of these compounds exhibited different variation trends between A549 and NCI-H460 cell lines, which indicated that these compounds could selectively inhibit the cell growth. The results would lay a foundation for further research on new anti-tumor drug development.  相似文献   

19.
The lowland rain forests of Central America are poorly known from the standpoint of management for timber production. We studied the stand dynamics of a logged Costa Rican rain forest under three different regimes of post-logging silvicultural treatment. The site was located on low hills with Ultisols in Holdridge's Tropical Wet Forest life zone. The Pentaclethra macroloba-dominated forest had been high graded before planned management began. Management of the 540 × 540 m (29.2 ha) experimental area began with a timber harvest in the whole area during 1989–1990, 4 trees ha−1 being cut overall for 10.1 m3 ha−1. The experimental plots were 180 × 180 m (3.24 ha), comprising a 100 × 100 m (1.0 ha) central permanent sample plot (PSP) with a 40-m wide buffer strip. Two types of post-harvest silvicultural treatment: liberation/refinement (in 1991) and shelterwood (in 1992) were applied under a complete randomized block design with three replicates, using logged but untreated plots as controls. PSP data reported are for the 1988–1996 period for individuals with ≥10 cm DBH. The most marked changes in forest structure were caused by silvicultural treatment, basal area under the liberation/refinement treatment being reduced to ca. 65% of its probable mature forest value. Recruitment exceeded mortality in the years following intervention under all three treatments, but forest structural recovery was slowest under the liberation/refinement treatment. Post-intervention mortality rates appeared higher under the liberation/refinement treatment than under the control or shelterwood treatments, though differences were not statistically significant. In relation to tree attributes, mortality rates increased with decreasing DBH increment, crown illumination and quality of crown form. Commercial DBH increments were higher under the liberation/refinement treatment than in control plots during the 1993–1996 period. On the basis of its response to intervention during the first seven years of management, the forest appears resilient and productive; trends over time in mortality rates under the most intense silvicultural regime require close attention however. Pentaclethra-dominated forests are important components of the productive forest resources of Costa Rica and Nicaragua and, given current deforestation rates in areas such as southern Nicaragua, it is now urgent that the existing biophysical knowledge of these forests be applied to forest conservation and management.  相似文献   

20.
Hispolon was the main antitumor active ingredient in Phellinus sensu lato species. In order to confirm the dual regulating estrogenic ingredient and obtain more effective natural estrogen replacement drugs, hispolon was separated from Phellinus lonicerinus (Bond.) Bond. et sing. Hispolon exhibited significant anti-proliferative effect against estrogen-sensitive ER (+) MCF-7 cells in the absence of estrogen, and exhibits antagonistic effects on 17β-estradiol (E2)-induced MCF-7 cell proliferation when E2 and the different concentrations of hispolon were treated simultaneously. Hispolon also inhibited the proliferation of estrogen-negative ER (−) MDA-MB-231 cells at the concentration of 5.00 × 10 5 M. The yeast two-hybrid experiments showed that hispolon had strong and non-selective effects on the estrogen receptor (ER) α and ERβ at a concentration of 1.00 × 10 6 M. The ERβ-binding ability of hispolon was larger than ERα in the concentration range of 1.00 × 10 9 M and 1.00 × 10 7 M. Hispolon could increase the body weight coefficient, serum E2 and progesterone contents in immature female mice at dose of 9.10 × 10 6 mol/kg, and increase coefficient of thymus and spleen in mice. The Gscores of hispolon-ERα and hispolon-ERβ docked complexes were − 7.93 kcal/mol and − 7.79 kcal/mol in docking simulations. Hispolon presented dual regulating estrogenic activities, which showed estrogenic agonist activity at low concentration or lack of endogenous estrogen, and the estrogenic antagonistic effect was stimulated at high concentrations or too much endogenous estrogen. Hispolon could be used for treating the estrogen deficiency-related disease with the benefit of non-toxic to normal cells, good antitumor effects and estrogenic activity.  相似文献   

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