𝔖 Bobbio Scriptorium
✦   LIBER   ✦

A study of the proline isomerisation in typical Italian wines

✍ Scribed by Calabrese, Massimo; Stancher, Bruno


Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
74 KB
Volume
79
Category
Article
ISSN
0022-5142

No coin nor oath required. For personal study only.

✦ Synopsis


In this paper the presence of the D isomer of proline in wine was investigated. The analyses were carried out on samples of two different types of Italian red wines, Merlot' and Cabernet', at different stages of aging during the period 1987±1996. The quantitative determination was performed using an RP±HPLC apparatus equipped with a diode array detector. Marfey's reagent, (1-¯uoro-2,4dinitrophenyl)-5-L-alanine amide (FDAA), was used for the derivatisation, and the obtained diastereomers were separated on a Supelcosil LC-18 analytical column (25 cm  0.4 cm id), adopting a gradient procedure and making use of water/acetonitrile buffer as the mobile phase. L-Norluecine was used as the internal standard for quantitative determination, and the detection of the derivatised components was made at a ®xed wavelength of 340 nm. The data obtained show an interesting correlation between the age of the sample and the presence of the D-proline isomer, due to a racemisation process that can be described as a ®rst-order kinetic reaction. The values of the kinetic constants obtained for the two wines are very similar but differ signi®cantly from those observed for wines aged for more than 10 years. This is probably due to enzymatic degradation processes, which can occur in wine after longer periods of time.


📜 SIMILAR VOLUMES


A vibrational study of poly (L-proline)
✍ John F. Rabolt; William Wedding; Kenneth W. Johnson 📂 Article 📅 1975 🏛 Wiley (John Wiley & Sons) 🌐 English ⚖ 421 KB 👁 2 views

## Abstract The far infrared spectra of poly(L‐proline) I (190–35 cm^−1^) and II (400–35 cm^−1^) were obtained in the solid state at both 300° and 110°K. A significant difference in the region below 100 cm^−1^ was observed. A very intense band located at 60 cm^−1^ in the infrared spectrum of form I

An infrared study on the conformation of
✍ Charles A. Swenson 📂 Article 📅 1971 🏛 Wiley (John Wiley & Sons) 🌐 English ⚖ 341 KB 👁 2 views

The infrared absorption of poly-L-proline in concentrated aqueous salt solutions was measured in the fundanierital region. Of primary interest were the carbonyl absorption of the peptide linkage and the methylene C-H bending absorption of the pyrrolidine ring. These spectral regions each show an add

The long-term use of psychotropic drugs:
✍ R. Fiorio; C. Bellantuono; M. Leoncini; G. Montemezzi; R. Micciolo; P. Williams 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 893 KB

## Abstract Four general practitioners (GPs) of Verona, a town in northern Italy of about 300,000 inhabitants, recruited in 1986 a cohort of 75 adult patients to whom they prescribed benzodiazepines or antidepressants for the “first time”. The patients, new users of psychotropic drugs, were 51 wome

The Italian registry of therapeutic aphe
✍ Stefano Passalacqua; Pietro Manuel Ferraro; Giampaolo Bresci; Valeria D'Ovidio; 📂 Article 📅 2011 🏛 John Wiley and Sons 🌐 English ⚖ 172 KB 👁 1 views

## Abstract Leukocytes are thought to play an important role in the pathogenesis of inflammatory bowel diseases; granulocyte–monocyte adsorptive (GMA) apheresis, an extracorporeal technique aimed at removing activated circulating leukocytes from the blood, may represent a safe and effective therape

Clinical efficacy of octreotide in the t
✍ Maria Di Bartolomeo; Emilio Bajetta; Roberto Buzzoni; Luigi Mariani; Carlo Carna 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 668 KB

## Background: The unsatisfactory control of neuroendocrine tumor growth with chemotherapy and/or interferon (ifn-2a) stimulated us to investigate the role of the somatostatin analogue octreotide (sms 201.995), which is reported to be highly effective in controlling carcinoid syndrome symptoms. oct