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In the search for novel compounds with both survivin inhibitory activity and fluorescence properties, 18 novel longifolene-derived tetralin pyrimidine compounds were designed using survivin as the target and synthesized from the sustainable natural resource longifolene.

A class of novel mogrol derivatives modified on A ring were synthesized. The screening result showed that indole-fused derivatives exhibited lower toxicity and better anti-inflammatory activity in LPS-induced RAW 264.7 cells model than mogrol and other compounds. Derivative B8 exerted superior inhibitory result of NO production (IC

Understanding the responses of lake sediment carbon process to climate change is an important part of a comprehensive understanding of lake carbon budget. To explore the effects of future rainfall increase on sediment carbon flux, undisturbed sediment samples were collected from the bottom of dry lake Barikun in Hami, Xinjiang for the incubation experiment. Based on the increase rate of precipitation (4 mm·10 a明确湖泊沉积物碳过程对气候变化的响应,是全面了解湖泊生态系统碳收支的重要环节。为探究未来降雨增加对沉积物碳通量的影响,本研究以新疆哈密巴里坤盐湖干涸湖底原状沉积物为对象,基于1960年以来新疆哈密地区降雨量增加速率(4 mm·10 a

Aims: The ripe fruit of Siraitia grosvenorii (Swingle) C. Jeffrey (Cucurbitaceae) is used in Traditional Chinese Medicine (TCM) for treatment of diabetes. The ripe fruit is very edible, nutritious and of high sweet taste, while the unripe fruit which is usually very bitter and not edible, has not been widely studied. Therefore, the aim of this study is to evaluate the antidiabetic activity of the unripe fruit of S. grosvenorii and to compare it with that of the ripe fruit as well as to determine their possible mechanism of action. Methodology: The method of streptozotocin-nicotinamide induced diabetic animal model in mice was employed and mice with blood glucose greater than 9.0 mmol/l were selected for treatment with unripe fruit extract (UFE) and ripe fruit extract (RFE) for 24 days. Alpha-glucosidase and alpha amylase enzymes inhibitory assays for determination of possible mechanism of action, were performed. Results: The RFE exhibited better efficacy in antidiabetic activity than the UFE, though the later displayed better potency in activity. The RFE, UFE (300 mg/kg) and glibenclamide exhibited significant (P

Passiflora edulis Sims (passion fruit) seeds are often discarded as byproducts during juice processing. In fact, the seeds are of considerable commercial value in the food and cosmetics industry because of their rich polyphenols, especially piceatannol. In this study, high-speed countercurrent chromatography (HSCCC) was applied for the separation of stilbene polyphenols from passion fruit seeds. The n-hexane-ethyl acetate-methanol-water (1:2:1:2.8, v/v) was found to be the optimum two-phase solvent for the preparation of two major stilbenes, scirpusin B (8) and piceatannol (9) with purities of 90.2% and 94.8%, respectively. In addition, a continuous semipreparative HPLC was applied to further purify the HSCCC fractions containing minor stilbenes and obtain four new piceatannol derivatives (1-4) along with three known ones (5-7). The structures of these new compounds were determined using spectroscopic methods, including NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and circular dichroism (CD). The isolated compounds were evaluated for α-glucosidase inhibitory activities in vitro. The result suggested that all of them exhibited more significant activity than acarbose, and passiflorinol B (2) had the strongest activity, with a IC50 value of 1.7 μM.

The roots of

Two new isoquinolines (

Solvent system selection is a crucial and the most time-consuming step for successful countercurrent chromatography separation. A thin-layer chromatography based generally useful estimate of solvent systems method has been developed to simplify the solvent system selection. We herein utilized the method to select a solvent system for off-line two-dimensional high-performance countercurrent chromatography to separate chemical compositions from a complex fraction of the Siraitia grosvenorii root extract. The first-dimensional countercurrent separation using chloroform/methanol/water (10:5.5:4.5, v/v) yielded four compounds with high purity and three mixture fractions (Fr I, III, and VII). The second-dimensional countercurrent separation conducted on Fr I, III, and VII using the hexane/ethyl acetate/methanol/water (4:6:6:4, 3:7:3:7, v/v) and chloroform/methanol/water (10:9:6, v/v) solvent systems, respectively, produced another four compounds. Four triterpenoids and four lignans were finally isolated, including two novel compounds. Hence, the generally useful estimate of solvent systems method is a feasible and efficient approach for selecting an applicable solvent system for separating complex samples. In addition, the off-line two-dimensional countercurrent chromatography method can improve both the peak resolution and the capacity of countercurrent chromatography. This article is protected by copyright. All rights reserved.

Aberrant destruction of the articular extracellular matrix (ECM) has been considered to be one of the pathological features of osteoarthritis (OA) which results in chondrocyte changes and articular cartilage degeneration. The MAPK signaling pathway serves a key role by releasing cartilage-degrading enzymes from OA chondrocytes. However, the use of MAPK inhibitors for OA is hindered by their potential long-term toxicity. Vicenin 3 is one of the major components of the Jian-Gu injection which is effective in the clinical treatment of OA. However, its potential impact on OA remain poorly understood. Therefore, the present study aimed to assess the effects of vicenin 3 on interleukin (IL)-1β-treated SW1353 chondrocytes, which mimic the microenvironment of OA. These chondrocytes were pretreated with vicenin 3 (0, 5 and 20 µM) for 1 h and subsequently stimulated with IL-1β (10 ng/ml) for 24 h. Nitric oxide (NO) production was measured using the Griess reaction, whereas the production of prostaglandin E2 (PGE2), matrix metalloproteinases (MMPs), A disintegrin-like and metalloproteinase with thrombospondin motifs (ADAMTSs), collagen type II and aggrecan were measured using ELISA. The mRNA expression of MMPs and ADAMTSs were measured using reverse transcription-quantitative PCR. The protein expression levels of MAPK were measured using western blotting. Vicenin 3 was found to significantly inhibit IL-1β-induced production of NO and PGE. Increments in the expression levels of MMP-1, MMP-3, MMP-13, ADAMTS-4 and ADAMTS-5 induced by IL-1β, in addition to the IL-1β-induced degradation of collagen type II and aggrecan, were all reversed by vicenin 3 treatment. Furthermore, vicenin 3 suppressed IL-1β-stimulated MAPK activation, an effect that was similar to that exerted by SB203580, a well-known p38 MAPK inhibitor. In conclusion, vicenin 3 may confer therapeutic potential similar to that of the p38 MAPK inhibitor for the treatment of OA.

Three new compounds (6

Three new compounds (6S,9S)-6′-galloyl-roseoside (1), purpurogallin ethyl carboxylate (2), and tibetana A (3) were isolated from 80% methanol extract of the leaves of Castanopsis tibetana Hance. Their structures were elucidated based on comprehensive spectroscopic methods and chemical data, including optical rotation, UV, MS, 1 D and 2 D NMR spectra. Compounds 1 and 3 were evaluated for their α-glucosidase inhibitory activity, pancreatic lipase inhibitory activity, and tyrosinase inhibitory activity.

The roots of Melastoma malabathricum subsp. normale (D. Don) Karst. Mey have been used in traditional ethnic medicine systems in China to treat inflammation-triggered ailments, such as trauma, toothache, and fever. Therefore, the aim of this study is to screen for compounds with anti-inflammatory activity in the title plant. The extract of M. malabathricum subsp. normale roots was separated using various chromatographic methods, such as silica gel, ODS C18, MCI gel, and Sephadex LH-20 column chromatography, as well as semi-preparative HPLC. One new complex tannin, named whiskey tannin D (1), and an undescribed tetracyclic depsidone derivative, named guanxidone B (2), along with nine known polyphenols (2–10) and three known depsidone derivatives (12–14) were obtained from this plant. The structures of all compounds were elucidated by extensive NMR and CD experiments in conjunction with HR-ESI-MS data. All these compounds were isolated from this plant for the first time. Moreover, compounds 1–4, 8, and 10–14 were obtained for the first time from the genus Melastoma, and compounds 1, 2, and 11–14 have not been reported from the family Melastomataceae. This is the first report of complex tannin and depsidone derivatives from M. malabathricum subsp. normale, indicating their chemotaxonomic significance to this plant. Compounds 1–12 were investigated for their anti-inflammatory activities on the production of the nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and compounds 1, 11, and 12 showed anti-inflammatory activities with IC50 values of 6.46 ± 0.23 µM, 8.02 ± 0.35 µM, and 9.82 ± 0.43 µM, respectively. The structure–activity relationship showed that the catechin at glucose C-1 in ellagitannin was the key to its anti-inflammatory activity, while CH3O- at C-16 of aromatic ring A in depsidone derivatives had little effect on its anti-inflammatory activity. The study of structure–activity relationships is helpful to quickly discover new anti-inflammatory drugs. The successful isolation and structure identification of these compounds, especially complex tannin 1, not only provide materials for the screening of anti-inflammatory compounds, but also provide a basis for the study of chemical taxonomy of the genus Melastoma.

Utilizing the distinct HMBC crossed-peak patterns of lower-field range (LFR; 11.80‒14.20 ppm) hydroxyl singlets, presented NMR methodology characterizes flavonoid metabolomes both qualitatively and quantitatively. It enables simultaneous classification of the structural types of 5-OH flavonoids and biogenetically related 2’-OH chalcones, as well as quantification of individual metabolites from (1)H NMR spectra, even in complex mixtures. Initially, metabolite-specific LFR 1D (1)H and 2D HMBC patterns were established via literature mining and experimental data interpretation, demonstrating that LFR HMBC patterns encode the different structural types of 5-OH flavonoids/2’-OH chalcones. Taking advantage of the simplistic multiplicity of the H,H-uncoupled LFR 5-/2’-OH singlets, individual metabolites could subsequently be quantified by peak fitting quantitative (1)H NMR (PF-qHNMR). Metabolomic analysis of enriched fractions from three medicinal licorice (Glycyrrhiza) species established proof-of-concept for distinguishing three major structural types and eight subtypes in biomedical applications. The method identified fifteen G. uralensis (GU) phenols from the six possible subtypes of 5,7-diOH (iso)flav(an)ones with 6-, 8-, and non-prenyl substitution, including the new 6-prenyl-licoisoflavanone (1) and two previously unknown compounds (4 and 7). Relative (100%) qNMR established quantitative metabolome patterns suitable for species discrimination and plant metabolite studies. Absolute qNMR with combined external and internal (solvent) calibration (ECIC) identified and quantified 158 GU metabolites. HMBC-supported qHNMR analysis of flavonoid metabolomes (“flavonomics”) empowers the exploration of structure-abundance-activity relationships of designated bioactivity. Its ability to identify and quantify numerous metabolites simultaneously and without identical reference materials opens new avenues for natural product discovery and botanical quality control and can be adopted to other flavonoid- and chalcone containing taxa.

A series of novel derivatives based on mogrol were designed and synthesized in attempt to improve anti-lung cancer activity. The cytotoxicity against human lung cancer cells including A549 and NCI-H460 were performed by Cell Counting Kit-8 (CCK8) assay in vitro. The screening result showed that compound 8f exhibited the strongest activity with an IC50 value of 4.47 μM against A549 cell, and could induce the cell apoptosis in a dose-dependent manner and arrest cell cycle at G0/G1 phase. Besides, compound 8f displayed anti-proliferation effect on A549 cell through inhibiting phosphorylation of signal transducer and activator of transcription 3 (STAT3). Furthermore, compared with morgol, compound 10a significantly improved the cytotoxicity against NCI-H460 with the IC50 value of 17.13 μM. The research stimulated the development of potential therapeutic agent for lung cancer from the natural mogrol.

Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis × E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis × E. urophylla leachates for 0–72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth.

In the course of a phytochemical and chemotaxonomical investigation for the Castanopsis (Fagaceae) species, fifteen compounds, including two triterpene hexahydroxydiphenoyl esters (1 and 2), seven gallotannins (3–9), three flavonoids (10–12), and three other compounds (13–15) were isolated from the leaves of Castanopsis fargesii Franch. Their structures were elucidated by means of spectroscopic methods and in comparison with published data. All these compounds were obtained from this species for the first time. Moreover, ethyl glucopyranoside (15) was firstly isolated from the genus Castanopsis. 6-O-Galloyl-β- d -glucose (3) and 3,4′,5,7-tetrahydroxyflavone (11) have not been reported from any species in Fagaceae family. The chemotaxonomic significance of these compounds was summarized.

Background Tomato fruit (Lycopersicon esculentum Mill.) has been suggested to be useful for the prevention of diabetes. Esculeoside A is the main saponin compounds in tomatoes. This study investigated the hypoglycemic effects and the underlying mechanism of esculeoside A in C57BLKS/Leprdb (db/db) mice. Methods Wild-type C57BLKS (db/dm) mice were used in the db/dm mouse group and db/db mice were randomly divided into 2 groups: untreated and treated db/db mouse groups. Esculeoside A (100 mg/kg) was administered by gavage for 56 days to the treated db/db mouse group. Distilled water was administered to the db/dm mouse group and the untreated db/db mouse group. The blood and liver biochemical parameters and the expression of liver insulin signaling-related proteins were examined. Results The results showed that esculeoside A reduced the fasting blood glucose (FBG) levels and improved the glucose tolerance. Further investigation revealed that hepatic protein expressions of total AMP-activated protein kinase (T-AMPK), phosphorylated AMP-activated protein kinase (p-AMPK), insulin receptor substrate-1 (IRS-1), and glucokinase (GCK) were significantly upregulated after esculeoside A treatment. In contrast, the hepatic protein expression of phosphoenolpyruvate carboxykinase (PEPCK) was significantly downregulated by esculeoside A treatment. Conclusion These findings suggested that esculeoside A has a potential of alleviating the metabolic abnormalities in db/db mice via regulation of AMPK/IRS-1 pathway. Our findings supported a possible application of esculeoside A as a functional supplement for diabetes treatment.

The aim of this study was to characterize hydrolyzable tannins in Polygonaceous plants, as only a few plants have previously been reported to contain ellagitannins. From Persicaria chinensis, a new hydrolyzable tannin called persicarianin was isolated and characterized to be 3-O-galloyl-4,6-(S)-dehydrohexahydroxydiphenoyl-d-glucose. Interestingly, acid hydrolysis of this compound afforded ellagic acid, despite the absence of a hexahydroxydiphenoyl group. From the rhizome of Polygonum runcinatum var. sinense, a large amount of granatin A, along with minor ellagitannins, helioscpoinin A, davicratinic acids B and C, and a new ellagitannin called polygonanin A, were isolated. Based on 2D nuclear magnetic resonance (NMR) spectroscopic examination, the structure of polygonanin A was determined to be 1,6-(S)-hexahydroxydiphenoyl-2,4-hydroxychebuloyl-β-d-glucopyranose. These are the second and third hydrolyzable tannins isolated from Polygonaceous plants. In addition, oligomeric proanthocyanidins of Persicaria capitatum and P. chinensis were characterized by thiol degradation. These results suggested that some Polygonaceous plants are the source of hydrolyzable tannins not only proanthocyanidins., Molecules, 26(2), art.no.337; 2021

A new C25 terpene consisting of C15 and C10 terpenes, sarcaglabrin A, and two new sesquiterpene dimers, sarcaglabrins B and C, were isolated from the aerial parts of a medicinal plant Sarcandra glabra used in Guangxi Zhuang Autonomous Region, China. Their structures were elucidated on the basis of detailed spectroscopic analyses including calculation of the ECD spectrum. Sarcaglabrin A was assigned as a conjugate of lindenane type sesquiterpene and ocimene type monoterpene, while sarcaglabrins B and C were elucidated to be lindenane sesquiterpene dimers. Their cytotoxicity against human cancer cell lines were evaluated.

Six new limonoids, munropins A−F (1–6), were isolated from the aerial parts of a Chinese medicinal plant, Munronia pinnata (Meliaceae). The structures of 1–6 were assigned by detailed analyses of their spectroscopic data. Munropins A (1) and B (2) are limonoids possessing a prieurianin skeleton with α,β-unsaturated γ-lactam moieties at C-17. Munropins C (3), D (4), and E (5) are also prieurianin type limonoids with an α,β-unsaturated γ-lactone moiety, an acetyl group, and an acetoxyacetyl group at C-17, respectively. Munropin F (6) was assigned as a nimbolinin type limonoid with a γ-hydroxy-α,β-unsaturated γ-lactone moiety.

To study the chemical constituents of Litchi chinensis pericarp.The compounds were isolated by Sephadex LH-20, MCI gel CHP 20 P, Toyopearl Butly-650 C, Toyopearl WH-40 F column chromatographies and semi-preparative HPLC, the structures were elucidated by NMR and mass spectroscopic MS data analysis.14 compounds were obtained and their structures were identified as quercetin( 1), chrysoeriol( 2),kaemperol-3-O-β-D-glucoside( 3), manghaslin( 4), isorhamnetin-3-O-robinobioside( 5), ( +)-gallocatechin( 6), (-) epicatechin-3-O-gallate( 7), cinnamtannin B-1( 8), isolariciresinol-9-O-β-D-xyloside( 9), ( +)-5-methoxyisolariciresinol-9-O-β-D-xylopyranoside( 10), vanillic acid( 11), 3, 4, 3’, 4’-tetrahydroxy biphenyl( 12), tachioside( 13) and isotachioside( 14).Compounds 1 ~ 7,9 ~ 14 are obtained from this plant pericarp for the first time.

Three new nor-clerodane diterpenoids, crotoeurins A-C (1-3), together with four known ones were isolated from the twigs and leaves of Croton euryphyllus. Among them, crotoeurin A (1) is a new nor-clerodane diterpenoid dimer with a unique cyclobutane ring via a [2+2] cycloaddition. Their structures were elucidated by spectroscopic analyses and the stereochemistry of 1 was confirmed by single-crystal X-ray diffraction analysis. Compounds 1-3 exhibited neurite outgrowth-promoting activity on NGF-mediated PC12 cells at concentration of 10 mu M. (C) 2015 Elsevier Ltd. All rights reserved.

Hydrodistillation of the fresh leaves of E.grandis×E.urophylla hybrids and pure species E.grandis, E.urophylla, E.pellita, E.camaldulensis, E. dunni, and E.saligna collected from the trees grown in Guangxi Huangmian Forest (China), afforded essential oils in yields varying from 0.24±0.15% to 5.36±0.28%, according to the species. Analysis by GC (FID) and GC/MS allowed the identification of 67 compounds, representing 82.55% to 91.03% of the total oil composition. The dominant compounds were 1,8-cineole in E.saligna, E.urophylla, E.grandis×E.urophylla, E.grandis, E.pellita and E. dunni (67.48, 57.12, 48.21, 23.64, 20.34, 20.22%), p-Cymene in E.camaldulensis,E. dunni and E.grandis(21.32, 14.74, 13.38%), α-pinene in E.grandis and E.grandis×E.urophylla (21.77, 15.55%), α-terpinene in E. dunni and E.grandis (17.96, 9.35%), α-terpineol in E.pellita and E.saligna (19.24,11.54%), respectively. Hierarchical Cluster Analysis separated the characterized essential oils into two groups, each constituting a chemotype. E.grandis×E.urophylla and E.urophylla were classified in the same group, while E.grandis in the other.

An environmentally friendly, efficient method for transforming alkynes into substituted benzenes catalyzed by p-toluenesulfonic acid monohydrate ( p-TsOH·H 2O) under solvent-free conditions has been developed, which conforms to the principles of "green" chemistry and overcomes the shortcomings of previous methods for the synthesis of substituted benzenes. The reaction is quite general and provides good to excellent yields.

A high-performance liquid chromatographic method (HPLC) with evaporative light scattering detection (ELSD) has been developed for fingerprint analysis of Flos Lonicerae. The samples were separated with an Agilent C18 column using acetonitrile (A) and 0.1% formic acid solution under gradient conditions (0→10 min：11.5%→15% A, 10→12 min：15% →22% A, 12→18min：22%→33% A; 18→30min: 33%→45% A) as the mobile phase at a flow rate of 0.8ml min−1 within 30 min. The ELSD conditions were optimized at nebulizer-gas flow rate 2.7 L min−1 and drift tube temperature 105°C. Precision experiments showed relative standard deviation (R.S.D.) of peak area and retention time were better than 2.5%, inter-day and intra-day variabilities showed that R.S.D. was ranged from 0.66% to 4.17%. Accuracy validation showed that average recovery was between 95.33% and 104.10%. The method was validated to achieve the satisfactory precision and recovery. Relative retention time and relative peak area were used to identify the common peaks for fingerprint analysis. There are nine common peaks in the fingerprint. The quality of sixteen batches of Flos Lonicerae samples was evaluated by hierarchical clustering analysis, which classfied all bacthes into two clusters. Furthermore, the contents of important medicinal compounds (chlorogenic acid, macranthoidin B and dipsacoside B) in different batches of Flos Lonicerae samples were determined simultaneously using the developed HPLC-ELSD method. The developed analytical procedure was proved to be a reliable and rapid method for the quality control of Flos Lonicerae.

Esculeoside A, the tomato saponins from Lycopersicon esculentum MILL, may be metabolized into various steroidal hormones such as pregnane derivatives that are expected to exhibit various bioactivities in the body, such as anti-osteoporosis, antimenopausal disorder and anti-tumor actions. In order to enrich large amount of esculeoside A for further scientific research, we firstly developed a high performance liquid chromatography (HPLC) with evaporative light scattering detection (ELSD) method for its quantification, and used it to examined the content of esculeoside A in different cultivated varieties of tomato fruits and tomato extract. Statistical analysis of the obtained data demonstrated that our method was simple, and has achieved desired linearity, precision and accuracy. Then we have explored the feasibility of using pectinase as a means for assisting esculeoside A extraction from fresh tomato fruits, and several factors such as the enzyme concentration, pH value of enzyme solution, temperature, incubation time which influenced on extraction were investigated. Moreover, in our previous study, the adsorption characteristics on several types of macroporous resins have been compared. Among them, D-101 resin showed the best separation behaviors on esculeoside A. So in the present paper, in order to get the best parameters for D101 adsorption, the adsorption kinetic curve, the appropriate ethanol concentration for elution and breakthrough volume were analyzed．

Triterpene hexahydroxydiphenoyl (HHDP) esters have only been isolated from Castanopsis species, and the distribution of these esters in nature is of chemotaxonomical interest. In this study, the chemical constituents of the leaves of Castanopsis fissa were examined in detail to identify and isolate potential HHDP esters. Together with 53 known compounds, 3,4-di-O-galloyl-1-O-purpurogallin carbonyl quinic acid (1) and 3,24-(S)-HHDP-2α,3β,23,24-tetrahydroxytaraxastan-28,20β-olide (2) were isolated and their structures were elucidated by spectroscopic and chemical methods. The polyphenols of the leaves were mainly composed of galloyl quinic acids, triterpenes HHDP esters, ellagitannins and flavonol glycosides. In particular, the isolation yields of 1,3,4-trigalloyl quinic acid and compound 2 were 1.53% and 0.27%, respectively, from the fresh leaves. The presence of lipid soluble HHDP esters of oleanane-type triterpenes as one of the major metabolites is an important chemotaxonomical discovery. Lipase inhibition activities and ORAC values of the major constituents were compared. The triterpene HHDP ester showed moderate lipase inhibition activity and myricitrin gave the largest ORAC value., Phytochemistry, 72(16), pp.2006-2014; 2011

Nonlinear least square is one of the unconstrained optimization problems. In order to solve the least square trust region sub-problem, a genetic algorithm (GA) of global convergence was applied, and the premature convergence of genetic algorithms was also overcome through optimizing the search range of GA with trust region method (TRM), and the convergence rate of genetic algorithm was increased by the randomness of the genetic search. Finally, an example of banana function was established to verify the GA, and the results show the practicability and precision of this algorithm.

Modal analysis of a simply supported beam with elastic support in vertical direction was conducted. Based on Bernoulli-Euler beam model, the first three nature frequency equations and the vibration mode function were obtained. And with different stiffness in vertical direction, the nature frequency equations were solved using numerical method, at the same time, curves of the relationship between support stiffness and nature frequency were acquired, and the corresponding functions were fitted with least square method simultaneously. Based on a typical beam structure, the accuracy of the functions was validated using finite element method, and the relative error was less than 3%.

A novel, efficient, and accurate fingerprinting method using high performance liquid chromatography-photodiode array detection has been developed and optimized for the investigation and demonstration of the variance in chemical properties among Siraitia grosvenorii fruits from different origins. The effects of growth stages, cultivated varieties, collection locations, and fruit portions of the herb on chromatographic fingerprints were examined. Eleven compounds were identified on chromatograms by comparing the retention time and UV spectrum of each peak separately with those of external references. The results revealed that chromatographic fingerprints, combining similarity or hierarchical clustering analysis along with reference compounds, could efficiently identify and distinguish S. grosvenorii fruits from different sources, which provided helpful clues for studying the plants' secondary metabolites and benefitted quality control.

Three new pregnane glycosides, 3-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3β,20-diol (1), 3-O-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3β,20-diol-20-O-β-D-glucopyranoside (2), 3-O-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3β,20-diol-20-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranoside (3) were isolated along with four known compounds, 4-7, from the leaves and stems of Brucea javanica. Their structures were determined by detailed analyses of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Brucea javanica were tested for the antifeedant activities against the larva of Pieris rapae. Compounds 1, 3, and 5 showed significant antifeedant activities after 72 h incubation.

Basic principles of dynamic design were proposed for the characteristics of machine dynamic performance. Take some curved-tooth bevel gear generator as research object. Its dynamic performance was analyzed and structure was optimized through theoretical analysis, finite element method (FEM) simulation and dynamic test analysis. Results show that these principles are suitable for dynamic performance optimization and design of machine tool.

The microstructure of the eutectic SnBi/Cu interface was investigated by transmission electron microscopy to study the growth mechanisms of the intermetallic compounds (IMCs). Although the growth kinetics of the total IMC layer were similar, the individual Cu3Sn layer grew faster on polycrystalline Cu than on single-crystal substrates. It was found that, on polycrystalline Cu, newly formed Cu3Sn grains with a smaller grain size nucleated and grew at both the Cu/Cu3Sn and Cu3Sn/Cu6Sn5 interfaces during reflow and solid-state aging. The consumption of Cu6Sn5 to form Cu3Sn was faster at the Cu3Sn/Cu6Sn5 interface. While on single-crystal Cu new Cu3Sn grains nucleated only at the Cu/Cu3Sn interface, the directional growth of the initial columnar Cu3Sn controlled the advance of the Cu3Sn/Cu6Sn5 interface.

Compensatory growth is a phase of accelerated growth apparent when favourable conditions are restored after a period of growth depression. To investigate if F-2 common 'all-fish' growth hormone gene transgenic common carp (Cyprinus carpio) could mount compensatory growth, a 9 week study at 29 degrees C was performed. The control group was fed to satiation twice a day throughout the experiment. The other two groups were deprived of feed for 1 or 2 weeks, respectively, and then fed to satiation during the re-feeding period. At the end of the experiment, the live masses of fish in the deprived groups were still significantly lower than those of the controls. During the re-feeding period, size-adjusted mean specific growth rates and mean feed intakes were significantly higher in the deprived fish than in the controls, indicating a partial compensatory growth response in these fish. No significant differences were found in food conversion efficiency between the deprived and control fish during re-feeding, suggesting that hyperphagia was the mechanism responsible for increased growth rates. The proximate composition of the deprived fish at the end of the experiment was similar to that of the control fish. This study is, to our knowledge, the first to report that fast-growing transgenic fish can achieve partial compensation of growth following starvation. (c) 2007 The Authors Journal compilation (c) 2007 The Fisheries Society of the British Isles.

The growth and energy budget for F-2 'all-fish' growth hormone gene transgenic common carp Cyprinus carpio of two body sizes were investigated at 29.2 degrees C for 21 days. Specific growth rate, feed intake, feed efficiency, digestibility coefficients of dry matter and protein, gross energy intake (I-E), and the proportion of I-E utilized for heat production (H-E) were significantly higher in the transgenics than in the controls. The proportion of I-E directed to waste products [faecal energy (F-E) and excretory energy loss (Z(E) + U-E) where Z(E) is through the gills and U-E through the kidney], and the proportion of metabolizable energy (M-E) for recovered energy (R-E) were significantly lower in the transgenics than in the controls. The average energy budget equation of transgenic fish was as follows: 100 I-E = 19.3 F-E + 6.0 (Z(E) + U-E) + 45.2 H-E + 29.5 R-E or 100 M-E = 60.5 H-E + 39.5 R-E. The average energy budget equation of the controls was: 100 I-E = 25.2 F-E + 7.4 (Z(E) + U-E) + 35.5 H-E + 31.9 R-E or 100 M-E = 52.7 H-E + 47.3 R-E. These findings indicate that the high growth rate of 'all-fish' transgenic common carp relative to their non-transgenic counterparts was due to their increased feed intake, reduced lose of waste productions and improved feed efficiency. The benefit of the increased energy intake by transgenic fish, however, was diminished by their increased metabolism.

Studies on the constituents of the unripe fruits of Siraitia grosvenori led to the isolation of three new cucurbitane triterpene glycosides, 11-oxomogroside III (10), 11-dehydroxymogroside III (11), and 11-oxomogroside IV A (12). Their structures were determined on the basis of detailed analyses of 1D, 2D-NMR spectroscopic methods. All of the compounds isolated from the unripe fruits of S. grosvenori were tested for cytotoxic activities against tumor cells, HCT-116 and SMMC-7721.

Three new nor-clerodane diterpenoids, crotoeurins A-C (1-3), together with four known ones were isolated from the twigs and leaves of Croton euryphyllus. Among them, crotoeurin A (1) is a new nor-clerodane diterpenoid dimer with a unique cyclobutane ring via a [2+2] cycloaddition. Their structures were elucidated by spectroscopic analyses and the stereochemistry of 1 was confirmed by single-crystal X-ray diffraction analysis. Compounds 1-3 exhibited neurite outgrowth-promoting activity on NGF-mediated PC12 cells at concentration of 10 mu M. (C) 2015 Elsevier Ltd. All rights reserved.

Mogroside V, a cucurbitane-type saponin, is not only the major bioactive constituent of traditional Chinese medicine Siraitiae Fructus, but also a widely used sweetener. To clarify its biotransformation process and identify its effective forms in vivo, we studied its metabolism in a human intestinal bacteria incubation system, a rat hepatic 9000g supernatant (S9) incubation system, and rats. Meanwhile, the distribution of mogroside V and its metabolites was also reported firstly. Seventy-seven new metabolites, including 52 oxidation products formed by mono- to tetra- hydroxylation/dehydrogenation, were identified with the aid of HPLC in tandem with ESI ion trap (IT) TOF multistage mass spectrometry (HPLC-ESI-IT-TOF-MS(n)). Specifically, 14 metabolites were identified in human intestinal bacteria incubation system, 4 in hepatic S9 incubation system, 58 in faeces, 29 in urine, 14 in plasma, 34 in heart, 33 in liver, 39 in spleen, 39 in lungs, 42 in kidneys, 45 in stomach, and 51 in small intestine. The metabolic pathways of mogroside V were proposed and the identified metabolic reactions were deglycosylation, hydroxylation, dehydrogenation, isomerization, glucosylation, and methylation. Mogroside V and its metabolites were distributed unevenly in the organs of treated rats. Seven bioactive metabolites of mogroside V were identified, among which mogroside IIE was abundant in heart, liver, spleen and lung, suggesting that it may contribute to the bioactivities of mogroside V. Mogroside V was mainly excreted in urine, whereas its metabolites were mainly excreted in faeces. To our knowledge, this is the first report that a plant constituent can be biotransformed into more than 65 metabolites in vivo. These findings will improve understanding of the in vivo metabolism, distribution, and effective forms of mogroside V and congeneric molecules.

Keywords: C. nudiflora; phenols; HP-20 macroporous resin Abstract: Objective To study the technological parameters of the purification process of phenols from Callicarpa nudiflora (C. nudiflora ) with HP-20 macroporous resin.Methods The kinetic adsorption and desorption experiments were carried out on HP-20 macroporous resin (HP-20) to optimize the separation process of phenols. Additionally, the effects of four parameters including adsorption flow rate, elute flow rate, volume of 10% ethanol and 50% ethanol solution for elution were explored by a L4/3 orthogonal experiment. Finally, content of phenols in samples before and after being treated by HP-20 were compared. Results The results showed that a good separation and purification of crude total phenols extract from C. nudiflora was achieved using HP-20. The optimum conditions were found to be: initial concentration of 50 mg·mL -1 , absorb flow rate of 1 mL·min -1 , elute flow rate of 3 mL·min -1 , 5 BV of 10% ethanol solution for prewash and 10 BV of 50% ethanol solution for desorption solvent. Conclusion The content of phenols is above 40% in C. nudiflora after being treated by HP-20, indicating that HP-20 could be successfully applied to enrich and purify phenols in C. nudiflora.

From the unripe fruits of Lo Han Kuo (Siraitia grosvenori), a Chinese medicinal plant, two new cucurbitane triterpene glycosides, 20-hydroxy-11-oxomogroside IA(1) (1) and 11-oxomogroside IIE (2), were isolated along with five known cucurbitane glycosides, 11-oxomogroside IA(1) (3), mogroside IIE (4), mogroside III (5), mogroside IVA (6), and mogroside V (7), and two flavonoid glycosides, kaempferol 7-O-alpha-L-rhamnopyranoside (8) and kaempferol 3,7-di-O-alpha-L-rhamnopyranoside (9). Their structures were determined on the basis of detailed analyses of 1D, 2D-NMR spectroscopic methods and by comparing with literature values. This paper describes the first investigation of unripe bitter Lo Han Kuo fruits.

In this study, we report three novel naturally occurring compounds, blapsins A (1) and B (2), and blapsamide (3) from the ethanol extract of the stink beetle, Blaps japanensis. The structures of these compounds were determined using spectroscopic methods. Compound 3 is a phenolic compound bearing a formamido group in the structure. Functional studies revealed that compounds 1 and 2 potently inhibited 14-3-3 protein-protein interactions (PPIs) with IC50 values of 9.2 and 10.0 mu M as determined by an ELISA assay, and 2.0 and 2.5 mu M in an FP assay, respectively. These compounds represent the first example of natural small-molecule 14-3-3 inhibitors. (C) 2012 Elsevier Ltd. All rights reserved.