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1.
Two quality control standards, total flavonoid glycosides of Epimedii Folium and epimedin C of Epimedii Wushanensis Folium, were used to systematically evaluate the quality of Epimedium wushanense T. S. Ying, so as to provide reference for its germplasm screening and resource utilization. Seven representative populations of E. wushanense covering its main distribution areas were uniformly sampled during the flowering period. There were significant quality differences among the populations of E. wushanense. According to the quality standard of total flavonoid glycosides, all populations were superior to the quality standard of the Chinese Pharmacopoeia for Epimedii Folium, with more than 1.5 % total flavonoid glycosides. The variation ranges of epimedin A, epimedin B, epimedin C, icariin and total flavonoid glycosides were 0.40–0.76 %, 0.51–0.83 %, 1.70–9.31 %, 0.40–1.23 % and 3.05–10.61 %, respectively. According to the quality standard of epimedin C, all populations were better than the quality standard of the Chinese Pharmacopoeia for Epimedii Wushanensis Folium, with more than 1.0 % epimedin C. The variation range of epimedin C was 2.22–10.06 %. When comparing the results of the two methods, a trend of slightly lower mean values was found for total flavonoid glycosides, except for the HBXW population. The quality of E. wushanense was superior to both the quality standard of Epimedii Folium and Epimedii Wushanense Folium in the Chinese Pharmacopoeia. Epimedin C was the most abundant component. Among the investigated populations, HBXW and HBGK exhibited the highest quality, and may provide excellent genetic resources for standardized cultivation. In addition, the habitat of these populations can also serve a reference for cultivation conditions.  相似文献   

2.
Four highly acylated diterpenoids, designated as pierisformotoxins A–D ( 1 – 4 , resp.), along with 26 known compounds, were isolated from the flowers of Pieris formosa. Among them, pierisformotoxins A and B ( 1 and 2 , resp.) were new highly acylated grayanane diterpenoids, of which the five‐membered ring A has undergone an oxidative cleavage between C(3) and C(4), followed by lactonization, to give rise to a five‐membered lactone ring between C(3) and C(5), differing from the previously reported grayanane diterpenoids with a 5/7/6/5 ring system. Results of the cAMP‐regulation‐activity assay showed that pierisformotoxin C ( 3 ) at 10 μM (inhibitory ratio (IR): 10.1%) or 2 μM (9.8%), and pierisformotoxin B ( 2 ) at 50 μM (13.9%) significantly decreased the cAMP level in N1E‐115 neuroblastoma cells (p<0.05).  相似文献   

3.
Two pairs of new neolignan enantiomers, (±)‐torreyayunan A ( 1a / 1b ) and (±)‐torreyayunan B ( 2a / 2b ), featuring a rare C‐8 ? C‐9′ linked skeleton, were isolated from leaves and twigs of Torreya yunnanensis. Their absolute configuration involving two chiral centers was determined by combined spectral and Density Functional Theory (DFT) calculation. This is the first report of the absolute configuration of this group of neolignans. Chirality 26:825–828, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

4.
采用HPLC测定不同品种淫羊藿黄酮类即淫羊藿苷、朝藿定A、朝藿定B、朝藿定C4种有效成分含量,结合主成分分析对不同品种淫羊藿进行质量分析与评价,并考察淫羊藿对大鼠肾阳虚保护作用.将实验动物随机分为阳虚模型对照组(模型组)、金匮肾气丸干预组(阳性组)、淫羊藿低(125 mg/kg)、中(250 mg/kg)、高(500 ...  相似文献   

5.
Four new flavonoids, mortatarins A–D ( 1 – 4 , resp.), along with eight known flavonoids ( 5 – 12 ) were isolated from the root bark of Morus alba var. tatarica. Their structures were established on the basis of spectroscopic data analysis, and the absolute configuration of 4 was determined by analysis of its CD spectrum. All isolates were tested for inhibitory activities against α‐glucosidase. Compounds 4, 7 , and 8 exhibited a significant degree of inhibition with IC50 values of 5.0±0.3, 7.5±0.5, and 5.9±0.2 μM , respectively.  相似文献   

6.
A solid‐state reaction route‐based LiTi2 ? xEux(PO4)3 was phosphor synthesized for the first time to evaluate its luminescence performance by excitation, emission and lifetime (τ) measurements. The LiTi2 ? xEux(PO4)3 phosphor was excited at λexci. = 397 nm to give an intense orange–red (597 nm) emission attributed to the 5D07F1 magnetic dipole (ΔJ = ±1) transition and red (616 nm) emission (5D07F2), which is an electric dipole (ΔJ = ±2) transition of the Eu3+ ion. Beside this, excitation and emission spectra of host LiTi2(PO4)3 powder were also reported. The effect of Eu3+ concentration on luminescence characteristics was explained from emission and lifetime profiles. Concentration quenching in the LiTi2 ? xEux(PO4)3 phosphor was studied from the Dexter's model. Dipole–quadrupole interaction is found to be responsible for energy transfer among Eu3+ ions in the host lattice. The LiTi2 ? xEux(PO4)3 phosphor displayed a reddish‐orange colour realized from a CIE chromaticity diagram. We therefore suggest that this new phosphor could be used as an optical material of technological importance in the field of display devices. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

7.
8.
Nucleotide sequences from the mitochondrial cytochrome c oxidase subunit I (COI) gene, comprising the standard barcode segment, were used to examine genetic differentiation, systematics, and population structure of cactus flies (Diptera: Neriidae: Odontoloxozus) from Mexico and south‐western USA. Phylogenetic analyses revealed that samples of Odontoloxozus partitioned into two distinct clusters: one comprising the widely distributed Odontoloxozus longicornis (Coquillett) and the other comprising Odontoloxozus pachycericola Mangan & Baldwin, a recently described species from the Cape Region of the Baja California peninsula, which we show is distributed northward to southern California, USA. A mean Kimura two‐parameter genetic distance of 2.8% between O. longicornis and O. pachycericola, and eight diagnostic nucleotide substitutions in the COI gene segment, are consistent with a species‐level separation, thus providing the first independent molecular support for recognizing O. pachycericola as a distinct species. We also show that the only external morphological character considered to separate adults of the two species (number of anepisternal bristles) varies with body size and is therefore uninformative for making species assignments. Analysis of molecular variance indicated significant structure among populations of O. longicornis from three main geographical areas, (1) Arizona, USA and Sonora, Mexico; (2) Santa Catalina Island, California, USA; and (3) central Mexico (Querétaro and Guanajuato), although widely‐separated populations from Arizona and Sonora showed no evidence of structure. A TCS haplotype network showed no shared haplotypes of O. longicornis among the three main regions. The potential roles of vicariance and isolation‐by‐distance in restricting gene flow and promoting genetic differentiation and speciation in Odontoloxozus are discussed. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 245–256.  相似文献   

9.
Three new Δ1‐3‐ketosteroids characterized with a 9‐OH, subergosterones A–C ( 1 – 3 ), together with five known analogs 4 – 8 , were obtained from the gorgonian coral Subergorgia rubra collected from the South China Sea. The structures of 1 – 3 , including their absolute configurations, were determined by comprehensive spectroscopic methods and electronic circular dichroism (ECD) experiments. Compounds 2 and 3 exhibited inhibitory antibacterial activities against Bacillus cereus with MIC values of 1.56 μM .  相似文献   

10.
11.
Neurotensin(8–13) (NTS(8–13)) analogs with C‐ and/or N‐terminal β‐amino acid residues and three DOTA derivatives thereof have been synthesized (i.e., 1 – 6 ). A virtual docking experiment showed almost perfect fit of one of the 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) derivatives, 6a , into a crystallographically identified receptor NTSR1 (Fig. 1). The affinities for the receptors of the NTS analogs and derivatives are low, when determined with cell‐membrane homogenates, while, with NTSR1‐exhibiting cancer tissues, affinities in the single‐digit nanomolar range can be observed (Table 2). Most of the β‐amino acid‐containing NTS(8–13) analogs (Table 1 and Fig. 2), including the 68Ga complexes of the DOTA‐substituted ones ( 6 ; Figs. 2 and 5), are stable for ca. 1 h in human serum and plasma, and in murine plasma. The biodistributions of two 68Ga complexes (of 6a and 6b ) in HT29 tumor‐bearing nude mice, in the absence and in the presence of a blocking compound, after 10, 30, and 60 min (Figs. 3 and 4) lead to the conclusion that the amount of specifically bound radioligand is rather low. This was confirmed by PET‐imaging experiments with the tumor‐bearing mice (Fig. 6). Comparison of the in vitro plasma stability (after 1 h) with the ex vivo blood content (after 10–15 min) of the two 68Ga complexes shows that they are rapidly cleaved in the animals (Fig. 5).  相似文献   

12.
Callus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog (MS) medium supplemented with different concentrations of 1-naphthylacetic acid (NAA), 6-benzyladenine (BA) and 2,4-dichlorophenoxyacetic acid (2,4-D) utilized hypocotyls with explant. The highest percentage of callus formation was the treatment supplemented with 3 mg L-1 NAA for A. muricata (100%) while for A. purpurea in lower percentage (75%). BA stimulated the formation of shoots in all the evaluated concentrations, being the concentration of 2 mg L-1 the one that induced the greater formation of shoots for A. muricata (23 shoots/explant) and A. purpurea (28 shoots/explant). The content of total phenols, flavonoids and antioxidant activity was measured in the callus obtained from both species. The results showed that a higher content of total phenols was quantified in callus of A. purpurea (27.8 mg g-1 dw) compared to A. muricata (23.2 mg g-1 dw). The highest content of total flavonoids was observed in the callus of A. purpurea (8.0 μg g-1 dw). Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydracil radical assay. The concentration required for 50% inhibition (IC50) of the 2,2-diphenyl-1-picrylhydracil radicals were 4.22 μg mL-1 in methanolic extracts of callus of A. muricata, while in extracts of callus of A. purpurea was 2.86 μg mL-1, in both cases was greater than that found for leaves. Callus culture of the species studied in this work represents an alternative for the production of natural antioxidants.  相似文献   

13.
Introduction – Flavonoids, the primary constituents of the petals of Nelumbo nucifera, are known to have antioxidant properties and antibacterial bioactivities. However, efficient methods for the preparative isolation and purification of flavonoids from this plant are not currently available. Objective – To develop an efficient method for the preparative isolation and purification of flavonoids from the petals of N. nucifera by high‐speed counter‐current chromatography (HSCCC). Methodology – Following an initial clean‐up step on a polyamide column, HSCCC was utilised to separate and purify flavonoids. Purities and identities of the isolated compounds were established by HPLC‐PAD, ESI‐MS, 1H‐NMR and 13C‐NMR. Results – The separation was performed using a two‐phase solvent system composed of ethyl acetate–methanol–water–acetic acid (4 : 1 : 5 : 0.1, by volume), in which the upper phase was used as the stationary phase and the lower phase was used as the mobile phase at a flow‐rate of 1.0 mL/min in the head‐to‐tail elution mode. Ultimately, 5.0 mg syringetin‐3‐O‐β‐d‐glucoside, 6.5 mg quercetin‐3‐O‐β‐d‐glucoside, 12.8 mg isorhamnetin‐3‐O‐β‐d‐glucoside and 32.5 mg kaempferol‐3‐O‐β‐d‐glucoside were obtained from 125 mg crude sample. Conclusion – The combination of HSCCC with a polyamide column is an efficient method for the preparative separation and purification of flavonoids from the petals of N. nucifera. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
Coussarea macrophylla (Mart .) Müll.Arg . (Rubiaceae) was collected in Ecuador, and the bark was extracted with AcOEt. Chromatographic separation afforded six novel 3,4‐secocycloartane and 3,4‐secodammarane triterpenes, named macrocoussaric acids A–F, together with the known metabolites secaubryenol and 3,4‐secodammara‐4(28),20,24‐triene‐3,26‐dioic acid. The structures of the new compounds were determined on the basis of their spectroscopic data. This is the first report of 3,4‐secocycloartane and 3,4‐secodammarane triterpenes occurring in a Coussarea species. Macrocoussaric acids A and B ( 2 and 3 , resp.) were found to be moderately cytotoxic against five different tumor cell lines.  相似文献   

15.
Organopromoter, 2‐aminoethanesulfonic acid was used to catalyze the synthesis of a series of structurally intriguing new hybrids thiazolyl acridine‐1,8(2H,5H)‐diones and dihydropyrido[2,3‐d : 6,5‐d′]dipyrimidine‐2,4,6,8(1H,3H,5H,7H)‐tetraones for the first time. 2‐Aminoethanesulfonic acid is a biobased organopromoter, used to generate four new bonds for the synthesis of new coupled thiazole‐based decahydroacridine‐1,8‐diones. Superior green credentials, operational simplicity, easy work‐up and recyclability of the catalyst are the key strengths of this method. The broad substrate scope, mild reaction conditions, short reaction time, cost effectiveness, high atom economy and good to excellent yields make the present method a distinct improvement over existing methods. Spectral (IR, 1H‐NMR,13C‐NMR, Mass) data and elemental analyses confirmed the structures of the titled products. A series of thiazolyl acridine‐1,8(2H,5H)‐diones and dihydropyrido[2,3‐d : 6,5‐d′]dipyrimidine‐2,4,6,8(1H,3H,5H,7H)‐tetraones were screened for their antimicrobial activity against four bacterial and three fungal strains.  相似文献   

16.
This study investigated the effects of 17α‐methyltestosterone (17α‐MT) on the physiological properties of gynogenetic topmouth culter (Culter alburnus). Five 17α‐MT concentration (0, 10, 25, 40, and 60 μg/g) groups were set up in Experiment 1, and three treatment and recovery methods of the above five concentrations were studied in Experiment 2. In Experiment 3, fish were fed with increasing concentrations of 17α‐MT (from 40 μg/g to 140 μg/g) in an outdoor pond. In Experiment 1, growth was promoted during the initial 60 days in the 10 μg/g group, whereas inhibition was first observed at 20 days after treatment in the 60 μg/g group. Increased concentration (40–60 μg/g) of 17α‐MT significantly inhibited the expression of FOXL2 and CYP19a gene but significantly activated the expression of AMH and DMRT1 gene. The levels of superoxide dismutase, estradiol, testosterone, growth hormone, and tetraiodothyronine in the 40 and 60 μg/g groups were significantly higher than those in the other concentration groups at 40 days after treatment. In Experiment 2, almost all indexes detected besides the expression of reproduction‐related genes in the 17α‐MT treatment groups were recovered to those in the control groups. All gonads observed in Experiments 1 and 2 remained in a primordial state after treatment with different concentrations of 17α‐MT. In Experiment 3, 100% of the detected gonads developed into testes at 126 and 460 days post‐fertilization after three‐month outdoor 17α‐MT induction. These results suggest that 17α‐MT affects the physiological processes related to sexual differentiation in topmouth culter and that feeding 17α‐MT with increasing dose in an outdoor pond provides an effective protocol for producing neo‐male topmouth culter.  相似文献   

17.
3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide test and alkaline phosphatase activity assay were employed to assess the effects of mixed trace elements including Zn2+, Ca2+, and Mn2+ plus total flavonoids or icariin from Epimedium koreanum on the proliferation and differentiation of primary osteoblasts in vitro. The results indicated that icariin (0.1, 1, and 10 μmol/L) and total flavonoids (0.06, 0.6, and 6 μg/mL) inhibited the proliferation and promoted the differentiation of primary osteoblasts. Mixed trace elements including Zn2+, Ca2+, and Mn2+ (0.1, 1, and 10 μmol/L) inhibited the proliferation and promoted the differentiation at 0.1 and 1 μmol/L, but inhibited the differentiation at 10 μmol/L. The effects of mixed trace elements including Zn2+, Ca2+, and Mn2+ plus total flavonoids or icariin from E. koreanum on the proliferation and differentiation of primary osteoblasts in vitro are complicated, and both synergistic and antagonistic effects are generated. The results suggest that there may be a potential cooperative action between flavonoids and trace metal elements on the proliferation and differentiation of primary osteoblasts by forming metal complexes. The combination model between flavonoids and trace metal elements is a pivotal factor for switching the biological effects from toxicity to activity, from damage to protection.  相似文献   

18.
An easy‐to‐prepare chiral CE method for the enantiomeric separation of 13 new amphetamine‐like designer drugs, using CDs as chiral selectors, was developed. Sulfated‐β‐CD was found to be the best chiral selector among the three used (sulfated‐β‐CD, caroboxymethyl‐β‐CD, dimethyl‐β‐CD). The separation of the analytes was achieved in a fused‐silica gel capillary at 20 °C using an applied voltage of +25 kV. The optimized background electrolyte consisted of 63.5 mM H3PO4 and 46.9 mM NaOH in water. Several electrophoretic parameters such as CD type, CD concentration (1 ? 40 mg/mL), buffer pH (2.6, 3.6, 5.0, 6.0), length of the capillary (70 ? 40 cm total length), amount of the organic solvent (methanol and acetonitrile) were investigated and optimized. Chirality 25:617–621, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

19.
In Brazil, insecticide resistance in Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) populations to pyrethroids and to the organophosphate (OP) temephos is disseminated. Currently, insect growth regulators (IGRs) and the OP malathion are employed against larvae and adults, respectively. Bioassays with mosquitoes from two northeast municipalities, Crato and Aracaju, revealed, in both populations, susceptibility to IGRs and malathion (RR95 ≤ 2.0), confirming the effectiveness of these compounds. By contrast, temephos and deltamethrin (pyrethroid) resistance levels were high (RR95 > 10), which is consistent with the use of intense chemical control. In Crato, RR95 values were > 50 for both compounds. Knock‐down‐resistant (kdr) mutants in the voltage‐gated sodium channel, the pyrethroid target site, were found in 43 and 32%, respectively, of Aracaju and Crato mosquitoes. Biochemical assays revealed higher metabolic resistance activity (esterases, mixed function oxidases and glutathione‐S‐transferases) at Aracaju. With respect to fitness aspects, mating effectiveness was equivalently impaired in both populations, but Aracaju mosquitoes showed more damaging effects in terms of longer larval development, decreased bloodmeal acceptance, reduced engorgement and lower numbers of eggs laid per female. Compared with mosquitoes in Crato, Aracaju mosquitoes exhibited lower OP and pyrethroid RR95, increased activity of detoxifying enzymes and greater effect on fitness. The potential relationship between insecticide resistance mechanisms and mosquito viability is discussed.  相似文献   

20.
Both enantiomers of three biologically relevant paraconic acids—MB‐3, methylenolactocin, and C75—were obtained with enantioselectivities up to 99% by kinetic enzymatic resolutions. Good enantiomeric excesses were obtained for MB‐3 and methylenolactocin, using α‐chymotrypsin and aminoacylase as enantiocomplementary enzymes, while C75 was resolved with aminoacylase. They all were evaluated for their antiproliferative, antibacterial, and antifungal activities, showing weak effects and practically no difference between enantiomers in each case. At high concentrations (16–64 µg/mL), (–)‐ C75 acted as an antimicrobial agent against Gram‐positive bacteria. Chirality 27:239–246, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

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