The Study On Variations Of Chemical Componets And Antioxidant Activity Of Red Wine During Decanting Process

Red wine is a commonly consumed beverage worldwide. Epidemiological data indicate that a moderate intake of red wine is associated with many well-known health-promoting properties such as free-radical scavenging and inflammatory modulation, metal chelating and enzyme modulation, reduction of the susceptibility of low-density lipoproteins (LDL) to oxidation both in vitro and in vivo, as well as inhibition of platelet aggregation, vasorelaxing activity and modulation of lipid metabolism. In this paper, variations of volatile components, organic acids and polyphenols, antioxidant activities of red wine after decanting were investigated. Pharmacokinetics on the active constitute of red wine was also studied.An HS-SPME-GC/MS method was developed for the determination of volatile components in red wine. The fiber for SPME was PDMS/DVB (65μm, Polydimethylsiloxane/Divinylbenzene). The vial was equilibrated at room temperature for 10 min, and then magnetic stirring began with the solid-phase microextraction performed at 35℃for 30 min. It was immediately followed by desorption of the analytes into the gas chromatograph injector, while fiber remained into the injector for the whole period of the split-less time. DB-5 capillary column (30 m×0.25 mm×0.25μm, Agilent) was chosen for GC analysis. The temperature programme was 50℃for 3 min, then raised to 160℃at 4℃·min-1, then raised to 280℃at 5℃·min-1 and hold for 10 min.39 and 46 volatile components of the two tested red wine were identified, respectively. Variations of the volatile components whose contents were higher in red wine were studied to investigate the optimal condition for decanting.A novel strategy using UPLC-MS with multivariate statistical analysis to rapidly explore potential chemical markers was proposed and validated. The samples were separated on a Diamonsil C18 column (250 mm×4.6 mm,5μm) using a mobile phase composed of methanol-0.1% formic acid under gradient elution. Analysis was performed in total ion chromatography mode (TIC) with negative electrospray ionization (ESI) interface within the m/z range of 100～1000. The developed method was successfully used to analyze the decanting red wine samples. The datasets of tR-m/z pair, ion intensity and sample code were subjected to principal component analysis (PCA) to compare the differences among the decanting red wine samples. Potential chemical markers were found which can be used to distinguish the decanting groups.A liquid chromatography-mass spectrometry (LC-MS) method has been developed and validated for the determination of 20 compounds in red wine including:tartaric acid, malic acid, amber acid, gallic acid, citric acid, protocatechuic acid, p-Hydroxybenzoic acid, catechin, protocatechuic aldehyde, gentisic acid, epicatechin, syringic acid, vanillic acid, caffeic acid,p-Coumaric acid, ferulic acid, resveratrol, myricetin, quercetin and luteolin. Separation was carried out with a Diamonsil C18 column (250 mm×4.6 mm,5μm). A gradient program was used with the mobile phase consisting of 0.1% acetic acid and methanol. Analysis was performed in selected ion monitoring (SIM) mode with negative electrospray ionization (ESI) interface. All the analytes showed good linearity (r> 0.9973, n= 5) in the concentration ranges. The average percentage recoveries were evaluated by calculating the ratio of detected amount versus added amount. The recovery of the method was in the range of 92.1%～108.3%, with RSD less than 5.0%. The method was validated for good accuracy, repeatability and precision, and was used as a valid analytical method to evaluate the variations of 20 compounds in red wine after decanting for different time under different conditions.The antioxidant activity of red wine was measured by different analytical methods including total phenols (TP), total flavonoids (TFO) and total anthocyanins (TA) determination, cupric reducing antioxidant capacity (CUPRAC), lipid peroxidation inhibition (TBARS),2,2-diphenyl-l-picrylhydrazyl (DPPH) and superoxide radical-scavenger activity (SRSA). These methods were used to evaluate the changes of antioxidant activity of red wine samples during the different decanting processes.A sensitive and efficient liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for the determination of p-coumaric acid (CA) in rat plasma. After addition of the internal standard (IS) hydrochlorothiazide and acidification with 2 mol·L-1 hydrochloric acid, plasma samples were extracted by ethyl acetate and separated on a Kromasil Cig column (200 mm×4.6 mm,5μm) using a mobile phase composed of methanol-0.5‰acetic acid (60:40, v/v) within a runtime of 6.0 min. Analysis was performed in selected ion monitoring (SIM) mode with a negative electrospray ionization (ESI) interface. The target ions were m/z 163.15 for CA and m/z 295.95 for IS. The linear range was 0.01026～15.39μg·mL-1 and the lower limit of quantification (LLOQ) was 0.01026μg·mL-1. The intra-day and inter-day precision (R.S.D.%) were lower than 10% and accuracy (R.E.%) ranged from-2.9% to 3.2%. The validated method was successfully applied to the comparative pharmacokinetic study of CA in rat plasma after oral administration of CA and freeze-dried red wine, respectively. It was found that both AUC and T1/2 of CA in freeze-dried red wine were increased significantly (p< 0.05) comparing with that in monomer. In addition, a double-peak profile could be observed from the concentration-time curves after oral administration of freeze-dried red wine.