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Background:Green tea, obtained from the plant Camellis sinensis, is one of the oldest drinks in the world and contains numerous bioactive compounds. Studies have demonstrated the efficacy of green tea in preventing obesity and cardiovascular diseases that may be related to the reduction of lipid levels. Aim:This study aimed to evidence, through a systematic review, the therapeutic potential of green tea on the lipid profile in preclinical studies in obese animals and clinical studies in obese individuals. Methods:This systematic review follows the recommendations of the preferred report items for systematic reviews and meta-analyses. The electronic databases, PubMed (Medline), Science Direct, Scopus, and Web of Science were consulted. Articles from January 2009 to December 2019 were selected. Results:This search resulted in twenty-nine articles were included cirtically reviewed. In experimental studies, green tea administration has been shown to reduce total cholesterol, triglycerides and low-density lipoprotein cholesterol in animals exposed to obesity-inducing diet. In humans’ studies green tea was not shown to be effective for obese lipid control. Because supplementation with green tea extract reduced total cholesterol, triglycerides, low-density lipoprotein for three months at a specific dose. Conclusion:Therefore, green tea appears to act as a protective agent for dyslipidemia in obesity-induced animals. In human studies, green tea has not been shown to be effective in controlling obese lipids.

Background: This work describes a fast, simple, sensitive, and low-cost method for the identification of resveratrol in different brands and varieties of red wines. Methods: It was developed based on a comparison of the UV-VIS spectra of the samples and samples enriched with different concentrations of the trans-resveratrol standard. The spectra were analyzed by chemometric principal component analysis (PCA) and multivariate calibration. Results: The PCA data indicated that only 4 main components made possible group samples based on the grape variety characteristics and/or production region. Conclusion: From the construction of partial least squares (PLS) and multiple linear regression (RLM) models, it was possible to predict the sample trans-resveratrol content with that sample showing similarities between the groups observed in the PCA and the samples used in the model constructions. The predicted trans-resveratrol present in these samples ranged from 0.29 to 23.3 mg L-1. This multivariate method suggested a good predictive capacity of determination of resveratrol concentrations in commercial red wines.

This work describes a comparison of HPLC and spectrophotometric methods to determine the variation of the polyphenolics catechin, gallic acid, epicatechin, rutin, quercetin and chlorogenic acid in bark extracts of Schinus terebinthifoliusRaddi (Anacardiaceae). This plant is a well-known medicinal plant that occurs in South and Central America and it is employed in folk medicine mainly as an antimicrobial, anti-inflammatory and antipyretic, and it is also commercialized as herbal medicine. Samples of S. terebinthifoliuswere collected from different habitats of the Brazilian semi-arid region and commercial samples were bought from local drugstores. The samples were submitted to ethanol : H2O extraction and the extracts were submitted to HPLC-DAD for the best separation of compounds. Besides, a validation method for quantification of the above chemical markers was obtained and the concentration of compounds was determined in all samples, including the reference sample and commercial herbal medicines. In the same way, a methodology based on simple UV-VIS spectrophotometric analysis was also developed and the concentration data of the chemical markers were obtained for all samples. Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) were carried out, and the six active compounds were determined and analyzed. The chromatograms showed similar chemical profiles but some differences in intensities were observed. HCA and PCA permitted us to group the samples with similar chemical composition, and paired multivariate analyses of the obtained sample compositions from HPLC/DAD and UV-VIS analyses showed that both methods are similar, and they permitted us to indicate the main chemical markers responsible for the quality of the herbal medicines.

This study assessed the anthelmintic activity of plant-derived compounds against gastrointestinal nematodes of goats using the egg hatch and larval motility assays. The compounds tested were saponins (digitonin and aescin) and their respective sapogenins (aglycones), hecogenin acetate and flavonoids (catechin, hesperidin, isocordoin and a mixture of isocordoin and cordoin). Additionally, cytotoxicity of active substances was analysed on Vero cell through 3-4,5-dimethylthiazol-2-yl,2,5diphenyltetrazolium bromide (MTT) and propidium iodide (PI) tests. Significant reduction on the egg hatching (P < 0.05) was seen only in the treatments with aescin (99%/EC50 = 0.67 mg mL−1) and digitonin (45%). The compounds that reduced the larval motility (P < 0.05) were digitonin (EC50 = 0.03 mg mL−1 and EC90 = 0.49 mg mL−1) and the hecogenin acetate (75%). The other sapogenins showed low anthelmintic activity. All the flavonoids showed low ovicidal (4–12%) and larvicidal (10–19%) effects. The aescin and digitonin showed low toxicity in PI test (viable cells >90%). Nevertheless, higher cytotoxicity was observed in the MTT assay, with IC50 of 0.20 mg mL−1 (aescin) and 0.0074 mg mL−1 (digitonin). Aescin and digitonin have a pronounced in vitro anthelmintic effect and the glycone portion of these saponins plays an important role in this activity. [ABSTRACT FROM AUTHOR]

An improved method to obtain naringin, a bitter flavored flavanone glicoside with proven biological activities, from grapefruit (Citrus x paradisiL.) peel waste is described. The proposed modification of the known process, which involves extraction with methanol and crystallization in water with the addition of dichloromethane, requires shorter processing time and reduced solvent volume. Due to the direct method employed, which did not require the 3-day air-drying stage, the hot extraction of fresh grapefruit albedo using methanol led to higher yields of naringin extract in half the time required. To evaluate the obtained naringin which possessed a wide range of pharmacological properties, it was subjected to chemical transformation into the flavone apigenin, an expensive and naturally-occurring flavonoid obtained in low yields.

Background: Bergenin, a compound derived from gallic acid, is a secondary metabolite of the plant Peltophorum dubium (Spreng.) Taub. Objective: In this study, we aimed to characterize the ability of bergenin to eliminate the radicals in non-biological systems. Methods: We evaluated bergenin's ability to protect erythrocytes from oxidative damage in a biological system. We have elucidated bergenin structure using nuclear magnetic resonance, X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry. We then evaluated its antioxidant capacity in vitro against DPPH· , ABTS· +, hydroxyl radicals, and nitric oxide, and determined its ability to transfer electrons owing to its reduction potential and ability to chelate iron. We also evaluated its protective capacity against oxidative damage produced by AAPH in erythrocytes, its hemolytic properties, its ability to inhibit hemolysis, and its ability to maintain intracellular reduced glutathione homeostasis. Results: Bergenin concentrations between 0.1 and 3mM significantly (p < 0.05) and dose dependently decreased formation of ABTS · +, DPPH·, nitrite ions, OH., reduced formation ferricyanide, ferrozine-Fe2+complex, inhibited AAPH-induced oxidative hemolysis of erythrocytes, raised GSH levels in the presence of AAPH, inhibited AAPH-induced lipid peroxidation in erythrocytes. Conclusion: Bergenin may represent a novel alternative antioxidant, with potential applications in various industries, including drugs, cosmetics, and foods.

The present paper describes a direct method for the determination of gallic acid, hydroxymethylfurfural, vanillic, caffeic, p-coumaric, ferulic, caftaric, cis-coutaric, fertaric and trans-coutaric acids in Brazilian red wines by direct injection employing reverse phase high performance liquid chromatography (RP HPLC DAD). The method was performed using a sample volume of 10 μL and the separation process was established employing a monolithic column. The method was applied for analysis of red wine samples collected from the São Francisco region, Bahia State, Brazil. Ten wine samples were analysed and the contents of caftaric acid varied from 13.28 to 46.83 mg L−1, cis-coutaric acid from 1.01 to 2.13 mg L−1, trans-coutaric acid from 2.13 to 17.56 mg L−1, fertaric acid from 1.11 to 2.43 mg L−1, ferulic acid from 0.31 to 3.97 mg L−1, hydroxymethylfurfural from 0.59 to 8.83 mg L−1, vanillic acid from 2.90 to 11.57 mg L−1, caffeic acid from 4.20 to 14.20 mg L−1, p-coumaric acid from 0.26 to 12.46 mg L−1and ferulic acid from 0.31 to 3.97 mg L−1.

Symmetrical temperature difference also known as the sap flow index (SFI) forms the basis of the Heat Field Deformation sap flow measurement and is simultaneously collected whilst measuring the sap flow. SFI can also be measured by any sap flow method applying internal continuous heating through the additional installation of an axial differential thermocouple equidistantly around a heater. In earlier research on apple trees SFI was found to be an informative parameter for tree physiological studies, namely for assessing the contribution of stem water storage to daily transpiration. The studies presented in this work are based on the comparative monitoring of SFI and diameter in stems of different species (Pseudotsuga menziesii, Picea omorika, Pinus sylvestris) and tree sizes. The ability of SFI to follow the patterns of daily stem water storage use was empirically confirmed by our data. Additionally, as the HFD multipointsensors can measure sap flow at several stem sapwood depths, their use allowed to analyze the use of stored water in different xylem layers through SFI records. Radial and circumferential monitoring of SFI on large cork oak trees provided insight into the relative magnitude and timing of the contribution of water stored in different sapwood layers or stem sectors to transpiration.

Bergenin (1) is a C-glucoside of 4-O-methylgallic acid with known antiarthritic activity attributed to modulation of cytokine production. The present study was undertaken to evaluate whether 1has antinociceptive properties in models of inflammatory pain and to investigate its possible mechanisms of action. Pretreatment with 1(12.5–100 mg/kg, ip) produced a dose-related inhibition of acetic acid-induced writhing in mice. Furthermore, treatment with 1(50 and 100 mg/kg) inhibited both the early and late phases in a formalin test. In addition, 1(50 and 100 mg/kg, ip) inhibited mechanical hyperalgesia, edema, and paw production of hyperalgesic cytokines (TNF-α and IL-1β) induced by complete Freund’s adjuvant. However, the local production of IL-10, an anti-inflammatory cytokine, was not altered by 1(100 mg/kg, ip). Treatment with 1produced a similar profile of antinociception in wild-type and IL-10-deficient mice. Mice treated with 1did not show any motor performance alterations or apparent systemic toxicity. The results presented herein demonstrate that bergenin has consistent antinociceptive and anti-inflammatory properties, acting by the inhibition of IL-1β and TNF-α production, and suggest its potential for the control of inflammatory pain.

The upward movement of water due to transpiration stops when soil water potential (Ψs) drops below leaf water potential (ΨL). Under these circumstances, water can move in any direction in the plant‐soil continuum through the passive conduits of roots and stems towards the lowest Ψs. This is generally termed as hydraulic redistribution (HR), but the positioning and orientation of the driving water potential gradient may vary. Any experimental method that can measure bi‐directional and low flows in the sapwood of roots and stems will be suitable to detect HR. Using one approach for measuring sap flow (the heat field deformation technique, HFD) in several forest species and sites across Europe, we were able to provide evidence on different types of HR: vertical hydraulic redistribution (VHR), horizontal hydraulic redistribution (HHR), foliar uptake (FU) and tissue dehydration (TD). VHR is the vertical water movement through roots in response to water potential differences between deep and topsoil, either hydraulic lift or hydraulic descent. HHR is the lateral water movement through roots in response to horizontal water potential gradients, namely under localised irrigation. FU is the water movement from crown to soil through stems when the crown is wetted by foggy weather. TD is the downward movement of water in stems or roots from above‐ground tree tissues to soil under prolonged drought or frost. Results from direct sap flow measurements indicated the vectoral and widespread nature of HR, a phenomenon of paramount importance for overall physiology and ecohydrology. Copyright © 2010 John Wiley & Sons, Ltd.

The ethyl acetate extract of leaves of Moldenhawera nutans Queiroz & Alkin (Leguminosae) furnished, besides methyl gallate and gallic acid, the flavonols named laricetrin, laricetrin 3-glucoside and laricetrin 3-galactoside as well as the new one named laricetrin 5-galloyl-3- ß-?-xylopyranoside. It also was isolated from the hexane extract: ß-sitosterol, lupenone, ß- amyrinone, a-amyrinone, lupeol, ß-amyrin, a-amyrin and a-tocopherol. The antioxidant activities of flavonoids were measured through DPPH radical scavenging and inhibition of auto-oxidation of ß-carotene methods. The structures of the compounds were determined by analyses of spectral data. This is the first report dealing with phytochemical studies of leaves of M. nutans. In addition this current work describes the unequivocal attribution of 1H NMR and 13C NMR data of laricetrin.

Thermolysis of three β-hydroxyacetylenes were studied with the second-order Møller–Plesset perturbation theory using a split valence polarization 6-31G(d) basis set. The obtained optimized geometries, atomic charge distributions and energy values are in agreement with the experimental measurements. The rate coefficients, calculated theoretically over the temperature range of 500–700K, are given by the Arrhenius equation: for the primary, logk1(s−1)=12.5–175.6kJmol−1(2.303RT)−1; for the secondary, logk2(s−1)=11.7–171.0kJmol−1(2.303RT)−1; and for the tertiary, logk3(s−1)=12.5–172.7kJmol−1(2.303RT)−1. The values of logA, from 11.7 to 12.5 (ΔS≠<0), indicate that these decompositions are concerted processes with a six-membered cyclic transition state.

The A-type proanthocyanidin, epigallocatechin-(2β→7,4β→8)-epicatechin, together with the known epicatechin, luteolin 3′β-d-glucopyranoside, chrysoeriol 7β-d-glucopyranoside and 2-methylpentan-2,4-diol, were isolated from leaves of Dioclea lasiophylla. The structures were established on the basis of their spectral data. Antioxidant activities of isolates were measured using the auto-oxidation of β-carotene in a linolenic acid suspension method.

The isolation is described of an unusual chlorinated diphenyl ether named methyl 3,5-dichloro-6-(6-hydroxy-4-methoxy-3-methoxycarbonyl-2-methylphenoxy)-2-hydroxy-4-methylbenzoate that was obtained from the trunk of Byrsonima microphylla(Malpighiaceae). The structure was elucidated by a spectroscopic data analysis, and the presence of this compound in heartwood was confirmed by HPLC and HPTLC analyses.

Chromium nitride (CrN) in its NaCl‐type phase has been widely studied through density functional theory (DFT) in order to analyze its electronic properties. By the means of DFT with the Becke's three parameter Lee‐Yang‐Parr (B3LYP) hybrid functional, the same stoichiometry is studied in two unreported hypothetical phases in addition to the nonsynthesized and previously reported zinc‐blende‐type phase. The cohesive energy of every structure is calculated, and the analysis of this quantity indicated that all crystals are stable and that there is an unreported phase more stable than the synthesized one. The calculated electronic dispersion relation and density of electronic states allowed for the determination that these three phases have a conducting behavior. The symmetry of some bands is determined as a result of the crystal field splitting for chromium dstates. The topology of the electron density was studied in order to determine its properties at bond critical points (BCPs). The form of the Laplacian of the density and its gradient trajectories allowed to locate ring critical points in these structures. From these calculations, it is concluded that all three phases are ionic crystals. The synthesized NaCl‐type phase is studied in order to compare and confirm the results. This work studies three hypothetical in addition to one experimental phases of chromium nitridethrough density functional theory methods. Two of these phases are orthorhombic, a zinc blende phase and the experimental NaCl‐type one. The calculations allow to show the band structure, density of states and topology of electron density for each crystal structure.

This work describes the isolation and quantification of rotenoids from crude organic extracts of different parts of Clitoria fairchildianaR. A. Howard (Leguminosae) by HPLC-DAD. The lipid composition and the Artemia salinacytotoxic activities of the isolates were also conducted. Clitoriacetal (1), 6-deoxyclitoriacetal (2), stemonal and stemonone were isolated by chromatographic procedures and identified by usual spectroscopic and spectrometric techniques. Clitoriacetal and 6-deoxyclitoriacetal were not found in all parts of the plant, such as leaves and petals, but in the roots they occur in higher concentration. The activity against brine shrimp revealed that the root extract (LD50= 158 ppm) was the more active.

Plant secondary metabolites, such as, specifically, alkaloids and terpenes, may present psychoactive properties that modify the function of the central nervous system (CNS) and induce neurotoxicity. Neurotoxicity involves the response of glial cells, mainly astrocytes, which play a fundamental role in the control of homeostasis of the CNS. Some Erythroxylumspecies are indigenous to the state of Bahia in Brazil. This study investigated the cytotoxic activity of the diterpene AEP-1, extracted from the fruit of E. passerinumin a GL-15 cell line, astrocytic, glial cells model. The effects on cell viability, analyzed by the MTT assay, demonstrated a dose-dependent cytotoxic effect, with maximum effect at 500 μg/mL of AEP-1, and with a reduction of about 40 and 47% on cellular viability after 24 h and 72 h treatment, respectively. Evidence for induction of apoptosis by AEP-1 was first obtained when GL-15 glial cells were incubated with 250 μg/mL AEP-1 causing reniform and/or pyknotic nuclei and apoptotic bodies revealed by chromatin staining with Hoechst 33258. Increase in DNA fragmentation was also observed by comet assays in cells incubated with 500 μg/mL of AEP-1. Moreover, cells exposed to a sub toxic dose of AEP-1 (250 μg/mL) showed significant changes in morphology – contraction of the cytoplasm and expansion of cellular projections – signifying the presence of astrocytic cytoskeletal protein and glial fibrillary acidic protein (GFAP). These findings indicated astrocytic cells as the target for terpene AEP-1 and suggest the involvement of glial cells with psychoactive symptoms observed in humans and animals after consumption of fruits of plants of the genus Erythroxylum.

Two new ceramides were isolated from the bulbs of Lepidaploa cotoneaster(Willd. ex Spreng.) H. Rob. [Vernonia cotoneaster(Willd. ex Spreng.) Less.)], in addition to germanicol, β-sitosterol, stigmasterol, 3-β-O-β-D-glucopyranosyl-sitosterol, lupeol, lupeoyl acetate and tiliroside. The structures of the new compounds were elucidated by spectral techniques (MS, 1H NMR, 13C NMR, HSQC, HMBC, DEPT, and TOCSY) and were compared with data reported in literature, and were established as 2S*,2′R*,3S*,4R*,11E)-N-[2′-hydroxyhenicosanoyl]-2-amino-nonadec-11-ene-1,3,4-triol (1) and (2S*,2′R*,3S*,4R*,8E)-N-[2′-hydroxytricosanoyl]-2-amino-nonadec-8-ene-1,3,4-triol (2). To establish the structure and to locate the double bond, the methyl ester of the fatty acid and dimethyl disulfide (DMDS) derivatives were prepared for both ceramides.

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