Recovery of Oligomeric Proanthocyanidins and Other Phenolic Compounds with Established Bioactivity from Grape Seed By-Products

Grape seeds are a copious part of the grape pomace produced by wine and juice industry and they represent an interesting source of phenolic compounds. Proanthocyanidins (PAs) are the main class of grape seed phenols and are important dietary supplements for their well-known beneficial properties. In this study enriched extracts obtained from Chardonnay and Pignoletto grape seeds were characterized for their proanthocyanidins and other minor phenolic compounds content and composition. Seed PAs were fractionated using Sephadex LH-20, using different ethanol aqueous solutions as mobile phase and analysed by normal phase HPLC-FLD-ESI-MS. Monomers, oligomers up to dodecamers and polymers were recorded in all samples. For both cultivars, the extracts showed a high content in PAs. The determination of other phenolic compounds was carried out using a HPLC-QqQ-ESI-MS and Chardonnay samples reported a greater content compared to Pignoletto samples. Contrary to PAs fraction, extracts obtained with ethanol/water 50/50 (v/v) presented a significant higher phenolic content than the others.This project was supported by University of Granada (project PPJI2017.16)

EPR investigation of direct oxyradical scavenging and metal chelation activities of chitosan as an alternative to sulfites in enology

Exposure to dissolved oxygen during the winemaking process adversely affects the sensory properties of wines such as loss of colour, aromatic defects and increase of astringency. For decades the management of juice browning in enology has been managed by adding sulphur dioxide as a powerful antioxidant and antimicrobial agent. However, since sulfites are growingly rejected by consumers because of their chemical nature and known allergenic properties, developing biologically relevant alternatives is an expanding field in enology. Recently chitosan, an abundant biopolymer obtained by deacetylation of chitin from animal or vegetal sources, has been recommended as alternative fining agent in wines, showing antimicrobial, biodegradable and non-allergenic properties. Chitin derivatives also demonstrated metal chelating effects (which slower oxidation in wines), interacting with grape polyphenols such as caftaric acid (whose enzymatic oxidation results in excessive browning [1]), and inhibiting (+)-catechin oxidation in model white wines [2]. Using electron paramagnetic resonance (EPR) techniques involving nitrones spin traps and standard oxyradical generating systems, this study presents for the first time complementary facets of the antioxidant action of chitosan, including direct scavenging of hydroxyl radical (a highly oxidizing species formed during wine oxidation) and chelation of metals (iron and copper). Experiments were conducted in aqueous medium, wine matrix, and commercial white wines, and different chitosans were tested at concentrations (0.1\uf02d2 g/L) allowed by enology regulations. Altogether, EPR data support the preferential use of chitosan as a reliable alternative for the reduction of sulphur dioxide to maintain wine freshness

Vine Physiology, Yield Parameters and Berry Composition of Sangiovese Grape under Two Different Canopy Shapes and Irrigation Regimes

Vitis vinifera L. adapts well to a scarce availability of water in the soil. However, in recent decades, the combination of thermal stress with prolonged water scarcity could have dramatic consequences on the vine’s physiological status. In this paper, we evaluated the effects of two canopy shapes and two irrigation regimes at veraison on vine physiology, yield parameters and grape composition through biochemical and molecular approaches. The water shortage strongly influenced the physiology of Sangiovese only when the stress was moderate to severe. Neither the water stress limited to veraison nor the canopy shape were able to influence the yield parameters and sugar content, and a strong induction of the expression of the genes involved in the biosynthesis of anthocyanins was recorded only in conditions of moderate-to-severe stress. This phenomenon led to an increase in the anthocyanin content in berry skins until the end of veraison. Conversely, no significant effects occurred in terms of biochemical and molecular performance after re-watering and at harvest. Though the shape of the canopy could play a role only under elevated temperature and prolonged drought, severe water stress can affect the vine physiology and berry ripening during the veraison stag

Characterization of Berry Aromatic Profile of cv. Trebbiano Romagnolo Grapes and Effects of Intercropping with Salvia officinalis L

Volatile organic compounds (VOCs) are secondary metabolites responsible for the aroma of grapes and the quality of wine. Apart from genetics, agronomic practices may impact the aroma composition and the concentration of volatiles in grape berries. The possible influence of intercropping with medicinal aromatic plants (MAPs) on the VOCs in grape berries’ profile has been poorly explored. Trebbiano Romagnolo is a white Vitis vinifera cultivar cultivated within the Italia region Emilia-Romagna. The study investigated, for the first time, the volatile organic profile of Trebbiano Romagnolo berries as well as the possible influences of intercropping with sage (Salvia officinalis L.) on the volatile composition of grape berries. A total of 48 free and bound aroma compounds were identified using solid phase extraction-gas chromatography-mass spectrometry (SPE-GC-MS). In the free aroma fraction, the main classes were C6 derivatives, alcohols, and benzenes, while in the bound aroma fraction, the major classes were benzenes, C13 norisoprenoids, and terpenes. The results obtained in this experiment indicate that intercropping with Salvia officinalis may influence volatile compounds in grape berries, an interesting result in cultivars considered neutral such as Trebbiano Romagnolo, providing new insights for exploring the complexity of the terroir and the role of agroecological strategies

Chitosan as an antioxidant alternative to sulphites in oenology: EPR investigation of inhibitory mechanisms

The efficacy against oxidative degradation in model and sulphite-free white wines of two commercial, insoluble chitosans (one being approved for winemaking) were investigated by electron paramagnetic resonance (EPR). Both compounds at various doses significantly inhibited the formation of \u3b1-(4-pyridyl-1-oxide)-N-t-butylnitrone (4-POBN)-1-hydroxyethyl adducts under normal wine storage conditions. Pre-incubation with 2 g/L chitosan followed by filtration had a better effect than adding 50 mg/L sulphur dioxide to the experimental Chardonnay wine on the release of 4-POBN adducts after 6 days of incubation with 100 \u3bcM iron(II). In a relevant photooxidative system acetaldehyde formation was significantly reduced after 6 days of incubation. Parallel EPR tests were performed to assess the importance of metal chelation (iron and copper) versus direct scavenging of hydroxyl radicals on the effect of chitosan. The present data support the potentiality of using biocompatible chitosan as a healthier complement and/or alternative to sulphur dioxide against white wine oxidative spoilage

Phases I-II Matched Case-Control Study of Human Fetal Liver Cell Transplantation for Treatment of Chronic Liver Disease.

Fetal hepatocytes have a high regenerative capacity. The aim of the study was to assess treatment safety and clinical efficacy of human fetal liver cell transplantation through splenic artery infusion. Patients with endstage chronic liver disease on the waiting list for liver transplantation were enrolled. A retrospectively selected contemporary matched-pair group served as control. Nonsorted raw fetal liver cell preparations were isolated from therapeutically aborted fetuses. The end points of the study were safety and improvement of the Model for End-Stage Liver Disease (MELD) and Child-Pugh scores. Nine patients received a total of 13 intrasplenic infusions and were compared with 16 patients on standard therapy. There were no side effects related to the infusion procedure. At the end of follow-up, the MELD score (mean ± SD) in the treatment group remained stable from baseline (16.0 ± 2.9) to the last observation (15.7 ± 3.8), while it increased in the control group from 15.3 ± 2.5 to 19 ± 5.7 ( p = 0.0437). The Child-Pugh score (mean ± SD) dropped from 10.1 ± 1.5 to 9.1 ± 1.4 in the treatment group and increased from 10.0 ± 1.2 to 11.1 ± 1.6 in the control group ( p = 0.0076). All treated patients with history of recurrent portosystemic encephalopathy (PSE) had no further episodes during 1-year follow-up. No improvement was observed in the control group patients with PSE at study inclusion. Treatment was considered a failure in six of the nine patients (three deaths not liver related, one liver transplant, two MELD score increases) compared with 14 of the 16 patients in the control group (six deaths, five of which were caused by liver failure, four liver transplants, and four MELD score increases). Intrasplenic fetal liver cell infusion is a safe and well-tolerated procedure in patients with end-stage chronic liver disease. A positive effect on clinical scores and on encephalopathy emerged from this preliminary study