Contributors: Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage Rennes (PEGASE); Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-INSTITUT AGRO Agrocampus Ouest; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro); Danone Nutricia Research Utrecht; Wageningen University and Research Wageningen (WUR); Chalmers University of Technology Göteborg; Universitat Politècnica de València = Universitad Politecnica de Valencia = Polytechnic University of Valencia (UPV); Science et Technologie du Lait et de l'Oeuf (STLO); Ingénierie des Agro-polymères et Technologies Émergentes (UMR IATE); Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro; Teagasc - The Agriculture and Food Development Authority (Teagasc); Instituto de Biologia Experimental e Tecnológica (IBET); Universidade Nova de Lisboa = NOVA University Lisbon (NOVA); Faculdade de Farmácia da Universidade de Lisboa; Universidade de Lisboa = University of Lisbon = Université de Lisbonne (ULISBOA); Norwegian University of Life Sciences (NMBU); Université de Bordeaux (UB); Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN); Université Claude Bernard Lyon 1 (UCBL); Université de Lyon-Université de Lyon-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE); Ege University - EGE (Izmir, Turkey); Catholic University of Leuven = Katholieke Universiteit Leuven (KU Leuven); University of Copenhagen = Københavns Universitet (UCPH); University of Gdańsk (UG); University of Leeds; University of Massachusetts Amherst (UMass Amherst); University of Massachusetts System (UMASS); Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA); Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE); Quadram Institute; Biotechnology and Biological Sciences Research Council (BBSRC); Fresenius; Bioénergétique et Ingénierie des Protéines (BIP); Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS); European Commission COST Action : FA1005 INFOGEST; INRAE; 'Healthy and Safe Food System (KB37) ' knowledge base program of the Dutch Ministry of Agriculture, Nature and Food Quality (LNV) : KB-37-001-007.
نبذة مختصرة : International audience ; In vitro digestion studies often use animal digestive enzyme extracts as substitutes of human gastric and pancreatic secretions. Pancreatin from porcine origin is thus commonly used to provide relevant pancreatic enzymes such as proteases, amylase and lipase. Rabbit gastric extracts (RGE) have been recently introduced to provide gastric lipase in addition to pepsin. Before preparing simulated gastric and pancreatic extracts with targeted enzyme activities as described in in vitro digestion protocols, it is important to determine the activities of enzyme preparations using validated methods. The purpose of this inter-laboratory study within the INFOGEST network was to test the repeatability and reproducibility of lipase assays using the pH-stat technique for measuring the activities of gastric and pancreatic lipases from various sources. Twenty-one laboratories having different pH-stat devices received the same protocol with identical batches of RGE and two pancreatin sources. Lipase assays were performed using tributyrin as a substrate and three different amounts (50, 100 and 200 µg) of each enzyme preparation. The repeatability results within individual laboratories were satisfactory with coefficients of variation (CVs) ranging from 4 to 8% regardless of the enzyme amount tested. However, the inter-laboratory variability was high (CV > 15%) compared to existing standards for bioanalytical assays. We identified and weighted the contributions to inter-laboratory variability of several parameters associated with the various pH-stat equipment used in this study (e.g. reaction vessel volume and shape, stirring mode and rate, burette volume for the automated delivery of sodium hydroxide). Based on this, we established recommendations for improving the reproducibility of lipase assays using the pH-stat technique. Defining accurate and complete recommendations on how to correctly quantify activity levels of enzyme preparations is a gateway to promising comparison of in vitro data obtained ...
Processing Request
No Comments.