Search results for " anthocyanin"

Ultrasound-Assisted Extraction, Centrifugation and Ultrafiltration: Multistage Process for Polyphenol Recovery from Purple Sweet Potatoes

2016

This work provides an evaluation of an ultrasound-assisted, combined extraction, centrifugation and ultrafiltration process for the optimal recovery of polyphenols. A purple sweet potato (PSP) extract has been obtained using ultrasonic circulating extraction equipment at a power of 840 W, a frequency of 59 kHz and using water as solvent. Extract ultrafiltration, using polyethersulfone (PES), was carried out for the recovery of polyphenol, protein and anthocyanin. Pre-treatment, via the centrifugation of purple sweet potato extract at 2500 rpm over 6 min, led to better polyphenol recovery, with satisfactory protein removal (reused for future purposes), than PSP extract filtration without cen…

Increase of trans-resveratrol in typical Sicilian wine using β-Glucosidase from various sources

2008

β-Glucosidase (EC 3.2.1.21) (β-G) from different sources were tested to increase the trans-resveratrol in some Sicilian wines by hydrolysing resveratrol glucoside. β-G from Aspergillus niger mould was tested as a crude and purified enzyme, and compared with the same enzyme from Saccharomyces cerevisiae yeast. Specific purification served to eliminate collateral enzyme activities so that β-G could be used simply and economically. Aspergillus niger β-G produced trans-resveratrol increases of up to 75%, with no change in physico-chemical properties and bouquet, and an increase in health and nutritional properties. S. cerevisiae β-G raised free-terpenol levels, but impaired wine colour due to a…

Green and Quick Extraction of Stable Biophenol-Rich Red Extracts from Grape Processing Waste

2021

The extraction of grape processing waste (wine pomace) via microwave-hydrodiffusion and gravity (MHG) from three different cultivars grown in Sicily (Syrah, Perricone and Nero d’Avola) rapidly affords aqueous extracts highly concentrated in valued biophenols including flavonoids, anthocyanins and phenolic acids. The method does not employ organic solvent, acid or base and does not require grinding or freeze drying of the wine pomace nor separation of the grape skins from seeds and stem. All the extracts have a pronounced stability as shown by their red-violet color fully retained after storage for more than a year (15 months) in freezer under air. Concentrations of phenolics up to…

EVOLUTION OF ANTHOCYANIN PROFILES FROM GRAPE TO WINE

2010

Aims: This study aimed at acquiring knowledge on the evolution of anthocyanins from grape to wine and the possibility of deducing the varietal origin of a wine from its anthocyanin profile. Methods and results: The anthocyanin “fingerprints”, or profiles, of a series of autochthonous Sicilian accessions and in the respective young wines were determined by HPLC-DAD in 2008. Data were evaluated by taking into account the development of percentages of side-ring disubstituted and trisubstituted anthocyanins, the ratio between acetylated and p-coumaroylated derivatives, and PCA results. From grape until the end of alcoholic fermentation, percentages of 3-glucosides of cyanidin, peonidin, delphin…

Influence of light exclusion on anthocyanin composition in "Cabernet Sauvignon"

2011

Effect of grafting on yield and quality of eggplant (Solanum melongena L.)

2013

Eggplants have fruits with different sizes, shapes and colours, according to the cultivar. Skin colour is due to anthocyanins, pigments located in the cell vacuole of fruit skin that belong to phenolic flavonoids, a powerful antioxidants group. Environmental conditions and growing techniques may influence fruits characteristics and their content of phenolic compounds. Grafting is a non chemical alternative for overcoming the effects of intensive and continuous cropping. The rootstocks preferred for eggplant are hybrids of tomato or tomato KVFN. Also species taxonomically close, as Solanum torvum, have been used and showed good vigour, compatibility and resistance to wilt disease. Informatio…

Polyphenol Characterization and Antioxidant Activity of Grape Seeds and Skins from Sicily: A Preliminary Study

2022

The interest in the consumption of health-promoting foods has led to identifying derivatives of the wine industry as products to increase the functional properties of different foods or to design new functional foods. The main goal of this study is to characterize and valorize byproducts and wastes of Sicilian grapes as new sources of bioactive components, from the perspective of a circular economy and a biorefinery approach. In particular, this research investigated: 1. the total phenolic content and antioxidant activities and 2. the phenolic profiles of free and bound fractions of defatted grape seeds and red grape skins from Sicily. Defatted grape seeds (DGS) and red grape skins (RGSK) a…

Effects of the Extraction Technology on Pomegranate Juice Quality

2020

Pomegranate juice is a rich source of phenolic components; its consumption has considerably increased throughout the world in recent years, due to its nutraceutical properties. Commercial juice production involves pressing the fruits. The aim of this study was to assess the influence of the pressing stage on pomegranate juice properties, in terms of value, duration of the applied pressure and juice yield in order to examine the influence of pressure level on volatiles and nutraceutical properties of the juice. Pomegranate fruits cv. Wonderful One were manually harvested and mechanically processed for extracting the juice by means of a shelling machine, a peristaltic pump and a pneumatic pre…

Anthocyanin profile and antioxidant activity of freshly squeezed pomegranate (Punica Granatum L.) Juices of sicilian and Spanish provenances

2016

Pomegranate (Punica granatum L., Punicaceae) fruit is traditionally consumed in several countries, especially in Middle East, and has gained increasing popularity all over the world due to its assumed health benefits. Juices derived from the arils of the seeds were shown to be rich in anthocyanin glucosides, typically composed of cyanidin, delphinidin, and pelargonidin. The aim of the present study was the characterization of diverse Sicilian and Spanish pomegranate accessions regarding their anthocyanin and total polyphenol contents using the Folin-Ciocalteu reagent. The anthocyanin profiles were determined by HPLC-DAD and LC-MS, and color parameters were characterized using the CIELAB coo…