Chemical Constituents from the Root Bark of Rodgersia Sambucifolia

A new demethylacetovanillochromene glycoside, 2,2‐dimethyl‐2H‐(8‐hydroxy‐6‐acetyl)‐[2,3‐b] pyran‐8‐O‐β‐D‐apiofuranosyl‐(1 →6)‐β‐D‐glucopyranoside ( 1 ), together with twenty‐three known compounds, have been isolated from the root bark of Rodgersia sambucifolia. These known compounds include two diterpenoids, three flavonoids, two catechins, four lignans, two benzenoids, two isocoumarins, two steroids and six monoterpene glycosides, which were determined by means of spectral analyses.     

Experience with wheat flour reference material

The Chemical Section of the National Office of Measures, Hungary (OMH) [1] embarked on the preparation of a wheat sample series as a Certified Reference Material [2] (CRM) in 1992. The practical implementation of the wheat sample series has shown that test- ing laboratories are in great need of easy-to-use flour reference samples to objectively and independently qualify wheat. To fill this need, we have developed a three-term flour reference sample series. The certification process was car-ried out according to ISO recommendations. Investigations of the long-term stability [3] and the application of wheat and flour CRMs are continuing. Wheat is one of the most widely grown crops in Hun- gary and it is one of the major determinative factors in the economy. Its uniform and objective qualification is of outstanding importance. There are well-equipped laborato-ries with sufficient experience to assess wheat flour quality, howev- er, proficiency testing has shown that certified samples need to be used to achieve exact and uniform measuring results. Received: 12 November 1999 Accepted: 16 August 2000     

Rapid Determination of Betulin in Betula platyphylla Outer Bark Using Near-Infrared Spectroscopy

A simple, rapid, and nondestructive method for the determination of betulin in the outer birch bark was developed using near infrared spectroscopy (NIRS). NIRS data of the outer birch bark collected throughout the year was preprocessed and analyzed by principal component analysis, which led to clear discrimination of the samples according to their harvest times. The reference content of betulin, a major constituent of the outer birch bark, was determined using ultra performance liquid chromatography with a diode array detector (UPLC-DAD). The optimized and validated analytical conditions of UPLC-DAD provided better separation and faster analysis time compared to a conventional HPLC method. Betulin content also showed seasonal variation and was higher in the samples collected during the summer season. Partial least squares calibration techniques were employed to estimate the relationship between the NIRS data and betulin contents. The spectral data showed high correlation coefficients (over 0.700) with betulin content. These results indicate that NIRS combined with UPLC can be used to determine the quality and to quantify the betulin content of the outer birch bark.     

Betulin and its natural resource as potential anticancer drug candidate seen by FT‐Raman and FT‐IR spectroscopy

The Fourier transform Raman and IR spectra of betulin (lup‐20(29)‐ene‐3β,28‐diol) crystalline powder were recorded and analyzed. The vibrational wavenumbers and the corresponding vibrational assignments were theoretically studied using the Gaussian 03 package. The calculated vibrational wavenumbers with the B3LYP density functionals are generally consistent with the observed spectra. A complete vibrational characterization of betulin modes has been proposed here for the first time. Based on the vibrational analysis, two direct applications of the results have been described. It was shown that the outer bark of Betula Pendula Roth (the birch tree) contains betulin as a major component along with minor amounts of betulinic acid (BA), lupeol and other pentacyclic triterpenes derivatives. Since the major disadvantage of betulin is its low solubility, giving rise to serious problems in making pharmaceutical formulations, several guest–host type of complexes of betulin–cyclodextrins have been prepared and analyzed using FT‐Raman spectroscopy. Based on the vibrational analysis, it was concluded that the OH and CH₂OH functional groups are free from chemical interactions with the cyclodextrin cavity. Copyright © 2010 John Wiley & Sons, Ltd.     

Secoiridoid Glucosides and Anti-Inflammatory Constituents from the Stem Bark of Fraxinus chinensis

Qin Pi (Fraxinus chinensis Roxb.) is commercially used in healthcare products for the improvement of intestinal function and gouty arthritis in many countries. Three new secoiridoid glucosides, (8E)-4′′-O-methylligstroside (1), (8E)-4′′-O-methyldemethylligstroside (2), and 3′′,4′′-di-O-methyl-demethyloleuropein (3), have been isolated from the stem bark of Fraxinus chinensis, together with 23 known compounds (4–26). The structures of the new compounds were established by spectroscopic analyses (1D, 2D NMR, IR, UV, and HRESIMS). Among the isolated compounds, (8E)-4′′-O-methylligstroside (1), (8E)-4′′-O-methyldemethylligstroside (2), 3′′,4′′-di-O-methyldemethyloleuropein (3), oleuropein (6), aesculetin (9), isoscopoletin (11), aesculetin dimethyl ester (12), fraxetin (14), tyrosol (21), 4-hydroxyphenethyl acetate (22), and (+)-pinoresinol (24) exhibited inhibition (IC₅₀ ≤ 7.65 μg/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leuckyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 1, 9, 11, 14, 21, and 22 inhibited fMLP/CB-induced elastase release with IC₅₀ ≤ 3.23 μg/mL. In addition, compounds 2, 9, 11, 14, and 21 showed potent inhibition with IC₅₀ values ≤ 27.11 μM, against lipopolysaccharide (LPS)-induced nitric oxide (NO) generation. The well-known proinflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6), were also inhibited by compounds 1, 9, and 14. Compounds 1, 9, and 14 displayed an anti-inflammatory effect against NO, TNF-α, and IL-6 through the inhibition of activation of MAPKs and IκBα in LPS-activated macrophages. In addition, compounds 1, 9, and 14 stimulated anti-inflammatory M2 phenotype by elevating the expression of arginase 1 and Krüppel-like factor 4 (KLF4). The above results suggested that compounds 1, 9, and 14 could be considered as potential compounds for further development of NO production-targeted anti-inflammatory agents.     

Control modeling of ash wood drying using process neural networks

For the control and system identification problems of the deceleration phase of the ash wood drying process, we propose a deceleration phase modeling method of ash wood drying using process neural networks with double hidden layers. This method applies time-varying characteristics of process neural networks and the ability to extract time-space cumulative effects. The time-varying characteristics of wood drying deceleration phase modeling under time series background are directly incorporated into the model. By comparison with traditional neural network modeling results, we prove that the model of process neural networks has better control accuracy, providing an idea to solve control and nonlinear system identification problems under a time series background.     

Scale-up of sonic energy for a major industrial application: ash conditioning for power utilities that use fluidized bed combustion

The paper describes a new, powerful, patented piece of sonic equipment that operates in the low sonic frequency range, at 104 Hz, with nominal power of 75 kW. It has been tested for both physical and chemical sonic effects. A large-scale industrial application is described — the conditioning and pacification of ash from utility coal combustion by fluidized bed combustion. A variety of additional applications is suggested, most of which have been briefly tested.     

Stability and Photoisomerization of Stilbenes Isolated from the Bark of Norway Spruce Roots

Stilbenes or stilbenoids, major polyphenolic compounds of the bark of Norway spruce (Picea abies L. Karst), have potential future applications as drugs, preservatives and other functional ingredients due to their antioxidative, antibacterial and antifungal properties. Stilbenes are photosensitive and UV and fluorescent light induce trans to cis isomerisation via intramolecular cyclization. So far, the characterizations of possible new compounds derived from trans-stilbenes under UV light exposure have been mainly tentative based only on UV or MS spectra without utilizing more detailed structural spectroscopy techniques such as NMR. The objective of this work was to study the stability of biologically interesting and readily available stilbenes such as astringin and isorhapontin and their aglucones piceatannol and isorhapontigenin, which have not been studied previously. The effects of fluorescent and UV light and storage on the stability of trans stilbenes were assessed and the identification and characterisation of new compounds formed during our experiments were carried out by chromatographic (HPLC, GC) and spectroscopic techniques (UV, MS, NMR). The stilbenes undergo a trans to cis isomerisation under extended UV irradiation by intramolecular cyclisation (by the formation of a new C-C bond and the loss of two hydrogens) to phenanthrene structures. The characterised compounds are novel and not described previously.     

氧弹燃烧灰化分光光度法测定有机物中的硅

采用氧弹燃烧灰化进行样品预处理 ,亚铁还原硅钼蓝分光光度法测定有机物中微量硅。通过试样分析和回收率实验 ,结果表明 ,方法的回收率为 95 %— 10 2 % ,可用于有机样品中硅的定量测定。     

Betulin,a Newly Characterized Compound in Acacia auriculiformis Bark,Is a Multi-Target Protein Kinase Inhibitor

The purpose of this work is to investigate the protein kinase inhibitory activity of constituents from Acacia auriculiformis stem bark. Column chromatography and NMR spectroscopy were used to purify and characterize betulin from an ethyl acetate soluble fraction of acacia bark. Betulin, a known inducer of apoptosis, was screened against a panel of 16 disease-related protein kinases. Betulin was shown to inhibit Abelson murine leukemia viral oncogene homolog 1 (ABL1) kinase, casein kinase 1ε (CK1ε), glycogen synthase kinase 3α/β (GSK-3 α/β), Janus kinase 3 (JAK3), NIMA Related Kinase 6 (NEK6), and vascular endothelial growth factor receptor 2 kinase (VEGFR2) with activities in the micromolar range for each. The effect of betulin on the cell viability of doxorubicin-resistant K562R chronic myelogenous leukemia cells was then verified to investigate its putative use as an anti-cancer compound. Betulin was shown to modulate the mitogen-activated protein (MAP) kinase pathway, with activity similar to that of imatinib mesylate, a known ABL1 kinase inhibitor. The interaction of betulin and ABL1 was studied by molecular docking, revealing an interaction of the inhibitor with the ABL1 ATP binding pocket. Together, these data demonstrate that betulin is a multi-target inhibitor of protein kinases, an activity that can contribute to the anticancer properties of the natural compound and to potential treatments for leukemia.