“Digestomica delle proteine: piattaforme integrate per l’identificazione di peptidi

bioattivi e funzionali derivati dagli alimenti”

Dr. Gianluca PicarielloIstituto di Scienze dell’Alimentazione (ISA) - CNR, Avellino

picariello@isa.cnr.it

Bologna, 21 ottobre 2016

1913 !

food protein

food-derivedpeptides

inactive

active (or immunogenic??)

FermentationEnzymatic/acid hydrolysisRipening (proteolysis) Gastrointestinal digestion

MILK DERIVED BIOACTIVE PEPTIDES

Caseins (78-80%)(phosphoproteins)

αs1-caseinαs2-caseinκ-caseinβ-casein

Whey proteins (18-20%)

α-lactalbuminβ-lactoglobulinlactoferrin

Bioactive peptides

Milk-derived bioactive peptides

1984

2009

Food derived-bioactive peptides

Do they have a functional role

Non-protein components of digestion buffers affect digestion

Digest from the entire gliadin fractionfrom hexaploid wheat

Digest from whole casein and whey protein fractions

Complexity of the food matrix

2011-2015

Including an intestinal (jejunal)step of simulated digestion villi BBM

VALIDATING THE DIGESTION MODELS

Ex vivo

In vivo

Absorption of bioactive peptides (bioavailability)

A few peptides (potentially immunogenic ratherthan bioactive) at very low amount detected in the basolateral chamber

Gastro-duodenal digests of milk proteinsapplied to the apical chamber

Case studies: milk, wheat, ancient cereals, meat, tree nuts

March 2016

Mature milk (2-4 weeks after term delivery) from 12 healthy donors:- Six mothers observing a strict milk (and dairy-products) free diet- Six mothers drinking a cup of bovine milk daily and eating dairy products

Peptide from BOVINE MILK Protein of origin (position)Uniprot

protein ID

Number of times

identified

Motherson milk-free diet

(N=6)

Milk-drinking mothers

(N=6)

YVEELKPTPEGDL β-lactoglobulin (42-54) P02754 2 - 2

YVEELKPTPEGDLEIL β-lactoglobulin (42-57) P02754 1 - 1

SDIPNPIGSENSEKTTM*PLW αs1-casein (180-197) P02662 1 - 1

Aug 2016

Concluding remarks

Many supposed food-derived peptides are not stable to gastrointestinal digestion

Stability to digestion should be assessed to confirm a possible (local or systemic)activity

The identification of digestion stable peptides should be performed on real foodsystems, using physiologically realistic digestion/absorption models

The characterization of the «digestome» requires specialized and specifically designedanalytical methodologies

Analysis of the protein "digestome" : needs of integrated approaches

bioinformatics

food

fractionation

immunoreactivity

cell biology

perspective: metagenomics

CREDITS

ISA-CNR

Gianfranco Mamone

Giuseppe Iacomino

PhD student: Luigia Di Stasio

Simonetta Caira (now ISPAAM)

Director: Sabato D’Auria

UNINA – Federico II

Prof. Pasquale Ferranti

Prof. Francesco Addeo (retired)