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1.
The article focuses on the optimization of the extraction process of biologically active compounds (BAC) from grape marc—a by-product of the wine industry. The influence of temperature, specifically 30 °C, 45 °C and 65 °C, and ethanol concentration in solutions, specifically 0–96% (v/v) on the extraction yield of polyphenols, flavonoids, tannins and anthocyanins, were investigated. The composition of individual polyphenols, anthocyanins and organic acids, antioxidant activity (DPPH and ABTS) and CIELab chromatic characteristics of the grape marc extracts (GME), were characterized. The microbiostatic and microbicidal effects in direct contact of GME with pathogenic microorganisms, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, were determined in vitro. The influence of extraction parameters on the total polyphenol content (TPC), total flavonoid content (TFC), tannin content (TC), total anthocyanin content (TAC) and their interdependencies were studied using information analysis. A mathematical model was developed on cubic spline functions. The analysis of individual compounds showed the presence of a wide range of flavonoids (procyanidin B2, procyanidin B1, hyperoside and quercetin), flavones (catechin), hydroxybenzoic acid derivatives (gallic, protocatechuic, p-hydroxybenzoic acids, m-hydroxybenzoic acid, syringic acid), hydroxycinic acid derivatives and ferulic acid methyl ester. The malvidol-3-glucoside was the main anthocyanin identified in the extract. A high amount of tartaric acid was also found. GME showed significant antimicrobial activity against Gram-positive bacteria and lower activity against Gram-negative bacteria.  相似文献   
2.
JPC – Journal of Planar Chromatography – Modern TLC - A study of quantitative analysis of some flavonoids in Satureja hortensis L. extracts is presented. The HPTLC analyses were...  相似文献   
3.
JPC – Journal of Planar Chromatography – Modern TLC - The separation and quantitative analysis of thymol in Satureja hortensis L. extracts is reported. The extracts were obtained by...  相似文献   
4.
Abiotic stress agents, among them metal stress, can cause oxidative damage to plant cells. In defense, plants can increase the production of secondary metabolites in order to mitigate the harmful effects caused by them. The purpose of this work was to evaluate the effect of two types of copper salts (CuSO4 and Cu(NO3)2), added in two different amounts in soil (150 mg/kg, respectively 300 mg/kg), on assimilating pigments, total polyphenols, antioxidant activity and the elemental composition of wheat. The obtained results were compared with those from control plants grown in the same conditions but without copper salts. The amount of assimilating pigments, total polyphenols, and antioxidant activity respectively increases or decreases in the plants treated with copper salts compared to the control depending on the stage of development of the plant. No significant damage induced in the leaves of the wheat plants treated with the selected salts was observed following the TEM analysis. In six-week-old plants it was observed by EDX analysis that the salts are transformed into nanoparticles. The bioactive compounds, elemental composition and their interaction is influenced by concentration of metal’s salt, type of salt and exposure period.  相似文献   
5.
JPC – Journal of Planar Chromatography – Modern TLC - Horseradish samples (Cochlearis armoracia L.) and mustard samples (Sinapis alba L.) were extracted with 70:30 (v/v)...  相似文献   
6.
JPC – Journal of Planar Chromatography – Modern TLC - The aim of the present work was to establish a proper high-performance thin-layer chromatographic (HPTLC) method for the...  相似文献   
7.
This study is focused on the determination of some important antibiotics from different classes in waste water samples using solid phase extraction followed by high performance liquid chromatography with two detectors, diode array and mass spectrometer in positive ionisation mode. The investigated antibiotics include three penicillins (amoxicillin, ampicillin, penicillin G), two cephalosporins (ceftazidime, ceftriaxone), and two tetracyclines (tetracycline, doxycycline). The studied antibiotics were extracted from waste water samples using hydrophilic-lipophilic balanced cartridges. The extraction of antibiotics from water matrices was tested at several pH values. The best recoveries were obtained at pH 3 and 7 respectively. Depending on the nature of antibiotic, the limits of detection and quantification were obtained in the range of 0.07–0.92 µg mL?1 and 0.21–2.77 µg mL?1 respectively. Influent and effluent waste water samples were collected from a Waste Water Treatment Plant from Romania in order to detect the studied antibiotics. The antibiotics detected in the influent waste water samples were ceftriaxone (334 µg L?1), tetracycline (146 µg L?1) and doxycycline (110 µg L?1). In effluent waste water samples no target antibiotics were detected.   相似文献   
8.
A high-performance liquid chromatography method is reported for the determination of antibiotics in water. The antibiotics were simultaneously preconcentrated by solid-phase extraction. High-performance liquid chromatography was performed on a C18 modified column with gradient elution in 25?min at 40°C. The separation was performed using gradient elution with 90:10 acetonitrile:water and 0.1% aqueous formic acid. The antibiotics were identified by diode array detection and mass spectrometry. The established method was suitable for the determination of antibiotics in surface water.  相似文献   
9.
The purpose of this study was to evaluate the sun protection factor (SPF) of cosmetic emulsions with the addition of hydroalcoholic apple extract. First, the total polyphenolic content, the antioxidant activity and SPF properties of the extracts obtained by sonication and refluxing were evaluated. The two extraction methods were improved using the central composite design. For cosmetic emulsion that contained a different concentration of apple extract (10–40%), a SPF value between 0.51 and 0.90 was obtained. The most efficient apple extract was obtained by reflux using 50% ethanol and a 60 min extraction time. The concentrated extract was incorporated in a cosmetic emulsion whose SPF maximum was 0.90. Accordingly, due to photoprotective properties, the apple extract can be a candidate for use in cosmetic formulations.  相似文献   
10.
JPC – Journal of Planar Chromatography – Modern TLC - Thin-layer chromatographic separation of U(VI), Th(IV), the lanthanides Ln(III), (La(III), Ce(III), Pr(III), Sm(III), Gd(III),...  相似文献   
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