Views
4 years ago

Available online at www.pelagiaresearchlibrary.com Study of ...

Available online at www.pelagiaresearchlibrary.com Study of ...

Available online at www.pelagiaresearchlibrary.com Study of

Available online at www.pelagiaresearchlibrary.com Pelagia Research Library Asian Journal of Plant Science and Research, 2012, 2 (5):570-576 Study of Ochratoxin: A complexation in coffee Pelagia Research Library ISSN : 2249-7412 CODEN (USA): AJPSKY Pauline Mounjouenpou 1 *, Fallo Justin 1 , Bernard Guyot 2 , Joseph-Pierre Guiraud 3 . 1 Institute of Agricultural Research for Development (IRAD), BP 2067, Yaoundé, Cameroon 2 CIRAD UPR Qualité Produits Pérennes TA80/16, 34398 Montpellier Cedex 5, France 3 UMR-IR2B (Agro-M/INRA/UM2), Université Montpellier II, Place Eugène Bataillon, 34095 Cedex 5, France. _____________________________________________________________________________________________ ABSTRACT To study the complexation of ochratoxin-A (OTA) by coffee in a real environment (in coffee-drink) and with some coffee constituents able to inter act with the OTA as caffeine, chlorogenic acid and arginine. The coffee drink was prepared according to the "filter"method. OTA complexation tests were done at 23°C and at 90-100°C using test tube and filter-paper. OTA was extracted with a methanol / sodium bicarbonate mixture at 3%, purified on the immunoaffinity column “ochraprep” and quantified by HPLC with a fluorimetric detection. The results give a high rate of OTA complexation by the constituents of the hot coffee-drink was obtained. It depends on the volume of the coffee drink and the chemical compound. When hot, the rate of complexation is about 100% with 40 ml of coffeedrinking. After 20 min of heating at 200 ° C, 86.6% of pure OTA were degraded against 12.4% of disappearance of the OTA due to the complexation by caffeine, 11.6% due to arginine and 6% due to chlorogenic acid. However, the products of complexation or degradation are not detectable by fluorimetry. Keywords: Complexation of OTA, drink coffee, caffeine, chlorogenic acid, arginine _____________________________________________________________________________________________ INTRODUCTION Ochratoxin A is a mycotoxin which is predominantly produced by molds of Aspergillus and Penicillium. It has nephrotoxic, teratogenic and immunotoxic properties. Ochratoxin - A contaminates several food stuffs. Its presence in coffee was reported for the first time in 1974 [8]. Since then, many studies report concentrations ranging between 0.4 and 80µg.kg -1 [7, 9, 19, 11, 6, 16, 12, 25]. Contamination levels of OTA in coffee can vary by region to origin [12], climatic conditions and the post - harvest treatment used. During technological treatments of coffee such as roasting and coffee-drinking preparation, some authors have noted a variation of the initial content of OTA. Much works has been published with conflicting results. Some report substantial reductions [27, 26, 3, 4, 16, 2, 17], others report only a slight reduction of OTA content [24, 20]. The coffee bean is rich in protein (10-15%), organic acids (mainly chlorogenic acids: 6-10%), alkaloids (including caffeine: 1 to 3%) [5]. Dissolved in water (drink coffee) or under the influence of temperature, some of these constituents of coffee are susceptible to inter act with the OTA and be degraded and/ or form complexes, and thus lead to reduce the initial content of OTA. The objective of this work was to study the complexation of OTA by coffee in a real environment (in coffee-drink) and with some coffee constituents that were able to inter act with the OTA such as caffeine, chlorogenic acid and arginine. 570

now available online - African Studies Centre - University of Oxford
africanstudies.ox.ac.uk
available online in PDF format - Sacramento County Office of ...
scoe.net
Read Online Wiley CPAexcel Exam Review 2016 Study Guide January: Regulation (Wiley Cpaexcel Exam Review Regulation) Full Book
ciyakiyeni
EBOOK ONLINE The Romance of Small-Town Chautauquas PDF ONLINE
Rufusvrt43
ECO 365 week 5 Team Assignment Competitive Strategies and Government Policies
studentwhiz
EBOOK ONLINE Curriculum Studies Guidebooks: Volume 1- Concepts and Theoretical Frameworks (Counterpoints) GET PDF
Donovang4t4
EBOOK ONLINE The Case of Edith Cavell: A Study of the Rights of Non-Combatants BOOK ONLINE
hiakupit
Read Online The Administrative State: A Study of the Political Theory of American Public Administration GET PDF
phoenixkaur
EBOOK ONLINE Global Classroom: An Essential Guide to Study Abroad (International Studies Intensives) PDF ONLINE
Rigbyt45
Read Online Land Law Concentrate: Law Revision and Study Guide BOOK ONLINE
phoenixkaur
EBOOK ONLINE Writing for Academic Success (SAGE Study Skills Series) GET PDF
uopholas
Available online - Institute of Social and Economic Research
iser.uaa.alaska.edu
EBOOK ONLINE Workbook for Nursing Assisting: A Foundation in Caregiving, 4e FULL ONLINE
Landonet4f
EBOOK ONLINE CLEP Social Sciences and History Study Guide: Test Prep and Practice Test Questions by Accepted, Inc. FULL ONLINE
truuacle
EBOOK ONLINE Global Classroom: An Essential Guide to Study Abroad (International Studies Intensives) GET PDF
Rigbyt45
EBOOK ONLINE Reading and Making Notes (Pocket Study Skills) GET PDF
Grierhgh
EBOOK ONLINE Reading, Writing and Reasoning: A guide for students (Open Up Study Skills) PDF ONLINE
Landonet4f
EBOOK ONLINE College Placement Test Study Guide: College Placement Exam Prep and Practice Test Questions BOOK ONLINE
truuacle
available here - Research Centre for Injury Studies - Flinders ...
nisu.flinders.edu.au
EBOOK ONLINE Improve Your Reading (Ron Fry s How to Study Program) FULL ONLINE
guwriadr
Online Graduate Certificate in Global Post-Disaster Studies ...
umb.edu
Evidence-Based-Practices-in-Online-Learning-Review-of-Online-Learning-Studies
clairebrooks
Read Online Macrobiotic Diet For Ipad
krisdoyle
EBOOK ONLINE The Stations of the Cross: A Catholic Coloring Book Devotional (Religious Inspirational Bible Verse Coloring Books For Grown-Ups) GET PDF
durdeyok