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81.
Hae Lim Kim Hae Jin Lee Dong-Ryung Lee Bong-Keun Choi Seung Hwan Yang 《Molecules (Basel, Switzerland)》2020,25(22)
The aim of this study was to determine the anti-osteoarthritic effects of LI73014F2, which consists of Terminalia chebula fruit, Curcuma longa rhizome, and Boswellia serrata gum resin in a 2:1:2 ratio, in the monosodium iodoacetate (MIA)-induced osteoarthritis (OA) rat model. LI73014F2 was orally administered once per day for three weeks. Weight-bearing distribution and arthritis index (AI) were measured once per week to confirm the OA symptoms. Synovial membrane, proteoglycan layer, and cartilage damage were investigated by histological examination, while synovial fluid interleukin-1β level was analyzed using a commercial kit. Levels of pro-inflammatory mediators/cytokines and matrix metalloproteinases (MMPs) in the cartilage tissues were investigated to confirm the anti-osteoarthritic effects of LI73014F2. LI73014F2 significantly inhibited the MIA-induced increase in OA symptoms, synovial fluid cytokine, cartilage damage, and expression levels of pro-inflammatory mediators/cytokines and MMPs in the articular cartilage. These results suggest that LI73014F2 exerts anti-osteoarthritic effects by regulating inflammatory cytokines and MMPs in MIA-induced OA rats. 相似文献
82.
Anion-exchange chromatography (Hamilton, PRP-X100) with inductively coupled plasma mass spectrometry (ICP-MS) is commonly used for the speciation of arsenic in environmental and biological samples. However, retentions for As species are frequently different because of the use of widely different mobile phases. In addition, chloride in matrices interferes with arsenic determination. In this study, we systematically investigated various mobile phases based on ammonium salts affecting arsenic retention to eliminate chloride interference chromatographically. Hence, various mobile phases based on ammonium salts, including NH4H2PO4, NH4HPO4, NH4Ac, NH4HCO3 and NH4NO3, were examined for reasonable resolution and to separate chloride from arsenic species. The best result was obtained with a mobile phase containing 30 mM NH4H2PO4 at pH 5.6, where the separation of arsenic species, including arsenite [As(III)], arsenate [As(V)], dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA)], was achieved within 9 minutes with reasonable resolution and free of chloride interference at its high level (500 mg L− 1). The detection limits for the arsenic species were in the range of 0.1-0.3 μg L− 1 with a direct injection of sample without removing matrix. Finally, the proposed method was used for the determination of arsenic species in contaminated soil and plant tissues. 相似文献
83.
Separation of Rubisco in Extracts of Plant Leaves by Capillary Electrophoresis with Sieving Polymers
《Analytical letters》2012,45(4):579-587
ABSTRACT Rubisco (Ribulose-1, 5-bisphosphate carboxylase/oxygenase; EC 4.1.1.39) was separated in extracts of plant leaves by capillary electrophoresis with replaceable polymers. Rubisco extracted from plant leaves was fully denatured into small (15.8 kDa) and large (52.9 kDa) subunits in the presence of excess sodium dodecylsulfate (SDS). SDS-Rubisco complexes were separated by using an uncoateda fused silica capillary filled with a replaceable polymer solution, with detection at 220 nm. A calibration plot of Rubisco concentration in plant extract versus peak area was linear over the concentration range of 0.09-1.2 mg mL?1 with a correlation coefficient (r2) of 0.995 and a detection limit of 0.05 mg mL?1. The reproducibility of migration times was less than 0.27% RSD (n=5) and reproducibility of peak area was better than 6.9% The recovery of Rubisco in leaf tissues through the extraction and analysis procedure was 78.2% (±4.8) and through the analysis procedure alone was 96.9% (±5.1). The proposed method was used for the quantification of Rubisco in protein extracts from leaves of a variety of plant species. 相似文献
84.
The efficient and rapid detection of bioactive compounds in complex matrices of different origins (natural or synthetic) is a key step in the discovery of molecules with potential application in therapy. Among them, molecules able to interact with nucleic acids can represent important targets.In this study, an optical DNA biosensor, based on surface plasmon resonance (SPR) transduction, has been studied in its potential application as new analytical device for drug screening. This device was applied to the analysis of pure synthetic or natural molecules and also to some fractions obtained by chromatographic separation of an extract of Chelidonium majus L. (great celandine), a plant containing benzo[c]phenanthridinium alkaloids having intercalating properties.The ability of these molecules to interact with the double stranded nucleic acid (dsDNA) immobilised on the sensor surface has been investigated. The optical sensing relies on the SPR-based bench instrument Biacore X™ and represents an example of multiuse sensor. The results obtained demonstrate the potential application of this device for the rapid screening of bioeffective compounds. The characteristics of the biosensor offer the possibility to be coupled to chemical analysis as in hyphenated technologies. 相似文献
85.
Sofia Zazouli Mohammed Chigr Patrícia A. B. Ramos Daniela Rosa Maria M. Castro Ahmed Jouaiti Maria F. Duarte Snia A. O. Santos Armando J. D. Silvestre 《Molecules (Basel, Switzerland)》2022,27(2)
Zizyphus lotus L. is a perennial shrub particularly used in Algerian folk medicine, but little is known concerning the lipophilic compounds in the most frequently used parts, namely, root bark, pulp, leaves and seeds, which are associated with health benefits. In this vein, the lipophilic fractions of these morphological parts of Z. lotus from Morocco were studied by gas chromatography–mass spectrometry (GC–MS), and their antiproliferative and antimicrobial activities were evaluated. GC–MS analysis allowed the identification and quantification of 99 lipophilic compounds, including fatty acids, long-chain aliphatic alcohols, pentacyclic triterpenic compounds, sterols, monoglycerides, aromatic compounds and other minor components. Lipophilic extracts of pulp, leaves and seeds were revealed to be mainly composed of fatty acids, representing 54.3–88.6% of the total compounds detected. The leaves and seeds were particularly rich in unsaturated fatty acids, namely, (9Z,12Z)-octadeca-9,12-dienoic acid (2431 mg kg−1 of dry weight) and (9Z)-octadec-9-enoic acid (6255 mg kg−1 of dry weight). In contrast, root bark contained a high content of pentacyclic triterpenic compounds, particularly betulinic acid, accounting for 9838 mg kg−1 of dry weight. Root bark extract showed promising antiproliferative activity against a triple-negative breast cancer cell line, MDA-MB-231, with a half-maximal inhibitory concentration (IC50) = 4.23 ± 0.18 µg mL−1 of extract. Leaf extract displayed interesting antimicrobial activity against Escherichia coli, methicillin-sensitive Staphylococcus aureus and Staphylococcus epidermis, presenting minimum inhibitory concentration (MIC) values from 1024 to 2048 µg mL−1 of extract. Our results demonstrate that Zizyphus lotus L. is a source of promising bioactive components, which can be exploited as natural ingredients in pharmaceutical formulations. 相似文献
86.
Klaudia Kowalik Magdalena Polak-Berecka Monika Prendecka-Wrbel Dominika Pigo-Zajc Iwona Nied
wied
Dominik Szwajgier Ewa Baranowska-Wjcik Adam Wako 《Molecules (Basel, Switzerland)》2022,27(3)
The biological activity of an in vitro digested infusion of Epilobium angustifolium (fireweed) was examined in a model system of intestinal epithelial and colon cancer tissues. The content of selected phenolic compounds in the digested aqueous extract of fireweed was determined using HPLC-ESI-QTOF-MS/MS. Biological activity was examined using the human colon adenocarcinoma cell lines HT-29 and CaCo-2 and the human colon epithelial cell line CCD 841 CoTr. Cytotoxicity was assessed by an MTT assay, a Neutral Red uptake assay, May-Grünwald-Giemsa staining, and a label-free Electric Cell-Substrate Impedance Sensing cytotoxicity assay. The effect of the infusion on the growth of selected intestinal bacteria was also examined. The extract inhibited the growth of intestinal cancer cells HT-29. This effect can be attributed to the activity of quercetin and kaempferol, which were the most abundant phenolic compounds found in the extract after in vitro digestion. The cytotoxicity of the fireweed infusion was dose-dependent. The highest decrease in proliferation (by almost 80%) compared to the control was observed in HT-29 line treated with the extract at a concentration of 250 μg/mL. The fireweed infusion did not affect the growth of beneficial intestinal bacteria, but it did significantly inhibit E. coli. The cytotoxic effect of the fireweed extract indicates that it does not lose its biological activity after in vitro digestion. It can be concluded that the fireweed infusion has the potential to be used as a supporting agent in colon cancer therapy. 相似文献
87.
Nikolaos Katsinas Amalia Enríquez-de-Salamanca Andreia Bento da Silva Maria Rosrio Bronze Soraya Rodríguez-Rojo 《Molecules (Basel, Switzerland)》2021,26(19)
Nowadays, increasing interest in olive pomace (OP) valorization aims to improve olive’s industry sustainability. Interestingly, several studies propose a high-value application for OP extracts containing its main phenolic compounds, hydroxytyrosol and oleuropein, as therapy for ocular surface diseases. In this work, the stability and accessibility of OP total phenolic and flavonoid content, main representative compounds, and antioxidant activity were assessed under different pretreatment conditions. Among them, lyophilization and supercritical CO2 extraction were found to increase significantly most responses measured in the produced extracts. Two selected extracts (CONV and OPT3) were obtained by different techniques (conventional and pressurized liquid extraction); Their aqueous solutions were characterized by HPLC-DAD-MS/MS. Additionally, their safety and stability were evaluated according to EMA requirements towards their approval as ophthalmic products: their genotoxic effect on ocular surface cells and their 6-months storage stability at 4 different temperature/moisture conditions (CPMP/ICH/2736/99), together with pure hydroxytyrosol and oleuropein solutions. The concentration of hydroxytyrosol and oleuropein in pure or extract solutions was tracked, and possible degradation products were putatively identified by HPLC-DAD-MS/MS. Hydroxytyrosol and oleuropein had different stability as standard or extract solutions, with oleuropein also showing different degradation profile. All compounds/extracts were safe for ophthalmic use at the concentrations tested. 相似文献
88.
Marie-Hélène Gouy Marie Dominique Blanchin Christian Périgaud 《Analytica chimica acta》2006,566(2):178-184
A LC/MS/ESI method is described to monitor 5′-monophosphate cytosine arabinoside (Ara-CMP) formed after incubation of an Ara-C prodrug in cell extracts. After addition of an internal standard and off-line treatment with perchloric acid, Ara-CMP is separated from Ara-C and endogeneous matrix components on a porous graphitic carbon stationary phase using gradient elution with a water/acetonitrile mobile phase containing formic acid. The results of method performances (accuracy, linearity, limit of quantification and repeatability) show that the method is acceptable for its intended use. 相似文献
89.
M. Baucells G. Lacort M. Roura M. D. Pascal M. T. Felipo 《International journal of environmental analytical chemistry》2013,93(1-2):61-70
Abstract A method for the direct determination of Cd in soil extracts by graphite furnace atomic absorption spectrosopy (GFAAS) has been developed. Optimum operating conditions, analyte modifiers and matrix interferences have been investigated. Characteristic amounts are 0.34pg for siliceous samples and 0.45 pg for calcareous soils. The precision has been based on ten replicate readings in standards, and was 1.6%. Cd has been determined by the proposed methods and the results have been compared with those obtained by ICP technique. 相似文献
90.
Şerife Tokaliogˇlu Şenol Kartal Alfer A. Güneş 《International journal of environmental analytical chemistry》2013,93(3):201-217
Abstract Extractable contents of heavy metals such as Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb and Bi in soil and plant tissue samples (fruit, leaf, twig and root) collected, along a distance of 1100 m to the West, from the surroundings of a metallurgical factory producing mainly zinc, cadmium and lead were determined by flame atomic absorption spectrometry (FAAS). In addition, the determinations of Ca and Mg, macro nutrient elements for plants, were also performed. Three extractant solutions were used for dissolution of soil samples, namely aqua regia (1 HNO3+ 3 HCl) for total metal analysis, 1 mol L?1 ammonium acetate for exchangeable metal contents, and a dilute acid mixture (0.1 M HCl in 0.025 M H2SO4) for acid soluble metal contents. A mixture of HNO3 and HClO4 was used to analyze the fruit samples. The analyses of the leaf, the twig, and the root tissue samples were made by dry ashing method. The detection limits of the metals were in the range of 0.04 to 0.45 μg/mL for all soil extracts and 0.01 to 1.50 μg/mL for the fruit samples. The recovery values for all the determinations were higher than 95%. The results obtained from the analyses of plant tissue and soil samples were evaluated using linear correlation analysis and concentration factors to identify the effect of the factory near the grape-vine area. 相似文献