The main metabolites of caffeic and ferulic acids (ferulic acid-4′-O-sulfate, caffeic acid-4′-O-sulfate, and caffeic acid-3′-O-sulfate), the most representative phenolic acids in fruits and ...vegetables, and the acyl glucuronide of ferulic acid were synthesized, purified, and tested for their antioxidant activity in comparison with those of their parent compounds and other related phenolics. Both the ferric reducing antioxidant power (FRAP) assay and the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging method were used. Ferulic acid-4′-O-sulfate and ferulic acid-4′-O-glucuronide exhibited very low antioxidant activity, while the monosulfate derivatives of caffeic acid were 4-fold less efficient as the antioxidant than caffeic acid. The acyl glucuronide of ferulic acid showed strong antioxidant action. The antioxidant activity of caffeic acid-3′-O-glucuronide and caffeic acid-4′-O-glucuronide was also studied. Our results demonstrate that some of the products of phenolic acid metabolism still retain strong antioxidant properties. Moreover, we first demonstrate the ex vivo synthesis of the acyl glucuronide of ferulic acid by mouse liver microsomes, in addition to the phenyl glucuronide.
Background and Aims
This study evaluated the impact that the non‐Saccharomyces yeasts, Torulaspora delbrueckii (TD), Lachancea thermotolerans (LT), Pichia kluyveri (PK), Metschnikowia pulcherrima ...(MP), Candida zemplinina (CZ) and Kazachstania aerobia (KA), in sequential inoculation with Saccharomyces cerevisiae (SC), had on the volatile chemical profile of Shiraz wine.
Methods and Results
Shiraz grape must was inoculated with monocultures of the non‐Saccharomyces yeasts, which were allowed to ferment until 2% v/v ethanol concentration was reached at which point, SC was added to complete the alcoholic fermentation. The control was SC in monoculture. The final wines were subjected to solid phase microextraction‐GC × GC‐time of flight‐MS to evaluate the untargeted volatile metabolite profile of each treatment. Each fermentation produced a unique chemical profile. The LT–SC sequential fermentation was the most significantly different from the control primarily in the ester, alcohol and terpene profile. The KA–SC sequential fermentation had the highest amount of volatile acidity, and the PK–SC sequential fermentation had a relatively high amount of acetaldehyde and a few esters. The MP–SC sequential fermentation also revealed a higher concentration of several esters. The TD–SC sequential fermentation was notable for its lack of a distinct pattern in comparison with that of the other fermentations.
Conclusions
Given these characteristics, the LT–SC sequential fermentation showed the most potential for increased chemical complexity of the Shiraz volatile profile.
Significance of the Study
The results demonstrate that there is no clear, singular trend for how different, non‐Saccharomyces species of yeast – once thought to be wholly unfavourable in wine fermentations – will impact wine chemistry, flavour or quality. Each species presents unique metabolic characteristics, many of which could be beneficial, and their potential application in the wine industry should be considered.
Background and Aims
The grapevine canopy microclimate, particularly temperature and relative humidity, is of crucial importance for predisposing grapes to lower or greater incidence of microbial ...infections. Because of global warming, the widely adopted leaf removal at veraison causes an increase in the temperature of the grape berry surface, leading to sunburn and deterioration of berry composition. Seeking a good alternative, a novel, pre‐flowering leaf removal was studied and compared with post‐flowering approaches using a multidisciplinary approach.
Methods and Results
The effect of timing of leaf removal on the microbial ecology was studied in a Pinot Noir vineyard during two extremely different vintages. The effectiveness of leaf removal in suppressing Botrytis cinerea was compared with that of fungicide application. Bunch compactness and potential for cost and energy savings were calculated. The results showed that earlier leaf removal offers greater potential for successful control of microbial infections. Pre‐flowering defoliation also led to lower bunch compactness (16–18%) accompanied by a substantial yield reduction (30% in 2010 and 24% in 2011).
Conclusions
In addition to improved microbial control, the lower yield from pre‐flowering defoliation can eliminate the need for bunch thinning and consequently reduces total energy consumption; thus, the technique can be considered to have good potential for more sustainable and cost‐effective management of the vineyard, saving 27% on costs and as much as 46% on energy.
Significance of the Study
The sustainability of a novel pre‐flowering defoliation in Pinot Noir was evaluated by studying the microbial ecology of the vineyard and by calculating the potential savings from reduction in spraying and energy.
In this study, Vitis vinifera L wines cv. Cabernet Franc, Merlot, Sangiovese and Syrah, 2006 and 2007 vintages, produced in São Joaquim, a new wine-producing region in southern Brazil, were ...evaluated. As phenolic compound content is one of the most important parameters in assessing wine quality and is possibly partially responsible for the beneficial health properties of wines, in this paper the levels of the main anthocyanins, flavonols, hydroxycinnamic acid and hydroxybenzoic acid (HPLC-DAD and HPLC-DAD–MS analysis) and the in vivo antioxidant activity in mice are reported. The antioxidant capacity of plasma was assessed through the reduction of ferric iron (FRAP). Lipid peroxidation (TBARS), carbonyl protein (CP), reduced glutathione (GSH) levels and the catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity were determined in livers of the test animals. The results for the phenolic compounds content of the wine samples were considered appropriate for quality red wines, and the wine consumption promoted a significant increase in FRAP and decreases in the TBARS and CP levels and in the CAT, SOD and GPx activity. Moreover, the phenolic content of the wines was positively correlated with the in vivo antioxidant capacity promoted by regular wine consumption.
Wine colour depends directly on the quantitative and qualitative profiles of anthocyanins, flavonols and hydroxycinnamic acids, as well as on their involvement in polymerization and co-pigmentation ...reactions. Pinot Noir is a grape variety with a low natural colour potential, often combined with problems of low colour stability for its wines during aging. The influence of leaf removal timing on grape colour related polyphenols was observed during maturation and at harvest time for the 2009 vintage “real scenario” conditions in two different vineyards in the Vipava Valley (Slovenia), known for its warm but windy climate. With different timing of leaf removal, a different microclimate can be achieved, with different light exposure for the specific plant tissue and different temperatures on berry surfaces. Phenolic compounds were characterised and quantified using HPLC/Vis. Three classes of polyphenols were affected by leaf removal timing, but with differing intensities and with some differences between locations. Hydroxycinnamic acids were affected only slightly, mostly at the beginning of the maturation period. Anthocyanins were significantly affected, while flavonols were the most affected by treatments in both vineyards and their concentration was clearly related to modification of the light within the canopy.
Non-alcoholic fatty liver disease (NAFLD) is defined as the accumulation of fat in liver cells, which causes serious health consequences. Animal and human studies suggest that the gut microbiota ...plays a role in the pathogenesis of NAFLD. Here, we investigated whether spinach consumption could ameliorate high-fat-diet-induced disturbances in certain intestinal bacterial groups and products derived from their metabolism, such as short-chain fatty acids (SCFAs) and microbial phenolic catabolites. Attention is also paid to blood lipids and glucose. In the study, a rat model of high-fat-diet-induced NAFLD was used. There were six experimental groups: NC (normal diet), NB (normal diet + 2.5% spinach), NA (normal diet + 5% spinach), HC (high-fat diet), HB (high-fat diet + 2.5% spinach) and HA (high-fat diet + 5% spinach). The rats consumed these diets for five weeks, and after that, they were sacrificed and plasma, urine, intestinal content, faeces and liver samples were taken. Biochemical parameters were analyzed in plasma, phenolic catabolites were quantified in the faeces, urine, plasma and liver by UPLC-ESI-MS/MS, and the analysis of the microbiota and SCFAs in the intestinal content was performed by qPCR and GLC. Consumption of a high-fat diet caused NAFLD and dislipaemia and altered the gut microbiota and the pattern of SCFAs and phenolic gut microbial catabolites. Supplementation with spinach partially ameliorated some alterations induced by the high-fat diet, in particular by increasing the Lactobacillus counts, reducing the fasting glucose and total and LDL-cholesterol and preventing excess liver cholesterol accumulation, thereby improving the values of the steatosis biomarkers.
In this paper, we investigate whether the analysis of stable isotope ratios D/H and 13C/12C in ethanol and acetic acid and of 18O/16O in water can be applied to the ingredients of “aceto balsamico di ...Modena IGP” (ABM) to evaluate their authenticity. We found that impurities in the extraction solution do not affect the 13C/12C of acetic acid and the D/H values of acetic acid are not affected under a composite NMR experiment. The standard deviation of repeatability and standard deviation of reproducibility are comparable in wine vinegar and ABM and generally lower than those quoted in the official methods. This means that the validation parameters quoted in the official methods can also be applied to the ingredients of ABM. In addition, we found no changes in the isotopic values from wine to vinegar and to ABM, and from the original must to the ABM must, providing experimental evidence that reference data from wine databanks can also be used to evaluate the authenticity of vinegar and ABM.
Gut microbiota may play a role in the pathogenesis of NAFLD. We investigated whether tomato juice consumption for 5 weeks could ameliorate high-fat diet-induced alterations in certain intestinal ...bacterial groups and products arising from their metabolism (short-chain fatty acids and microbial phenolic catabolites). For this, we used a rat model with NAFLD induced by a high-fat diet, involving four experimental groups: NA (standard diet and water), NL (standard diet and tomato juice), HA (high-fat diet and water) and HL (high-fat diet and tomato juice). The onset of NAFLD impacted the gut microbiota profile, reducing the abundance of Bifidobacterium and Lactobacillus and increasing that of Enterobacteriaceae. Also, reduced concentrations of propionate, butyrate and phenolic catabolites and an increased acetate to propionate (Ac : Pr) ratio were observed. Tomato juice intake partially ameliorated high-fat diet-induced disturbances, particularly by increasing Lactobacillus abundance and diminishing the Ac : Pr ratio, suggesting a potential improvement of the metabolic pattern of NAFLD.
•UPLC-QqQ-MS/MS profiling of 58 phenols in 173 wines, 4 red and 6 white grape varieties.•Many phenols as varietal markers, efficacy of differentiation by SLDA >95% in all cases.•Potent ...differentiators: peonidin 3-(6″-acetyl)-glucoside and taxifolin for red, cis-piceid for white wines.•Anthocyanin composition was useful for elucidating diverse typical colour attributes.•trans-fertaric acid, isorhapontin, phlorizin, quercetin 3-rhamnoside, myricitrin were typical for Plavac mali red wine.
Targeted ultra-performance liquid chromatography with triple quadrupole mass spectrometric (UPLC-QqQ-MS/MS) profiling of phenolic compounds was utilised for varietal differentiation of 173 wines made from four red and six white grape varieties. Among 58 identified phenols many were found relevant as exclusive or partial discriminators between wines. Successful differentiation models were built by linear discriminant analysis with the percentage of correct classification higher than 95% in all cases, with peonidin 3-(6″-acetyl)-glucoside and taxifolin as the most potent differentiators between red, and cis-piceid between white monovarietal wines. Diverse typical colour attributes among the monovarietal wines were tentatively ascribed to the variations in the composition of monomeric anthocyanins. Plavac mali red wine exhibited the most specific composition, and its most typical samples were distinguished by the abundance in trans-fertaric acid, isorhapontin, phlorizin, quercetin 3-rhamnoside, and myricitrin. Despite positive correlations with particular astringent flavonols, the typical astringency of Plavac mali wine remained unresolved.