interactions of phenolic compounds with ovalbumin...allergy [2]. interactions between phenolic...

Ovalbumin (OVA) is the major protein in egg white and can cause allergy mainly in infants and young children [1]. Egg allergy is an IgE

mediated reaction and is one the most common food allergies. So far, the avoidance of the egg has been the unique way to prevent this

allergy [2]. Interactions between phenolic compounds (caffeic, chlorogenic, ferulic, gallic and tannic acids, quercetin and resveratrol) with

OVA form complexes and can contribute to decrease the egg allergenicity. Thus these interactions were studied by spectroscopic

techniques and in silico.

Interactions of Phenolic Compounds with Ovalbumin

Introduction

Materials and Methods

Conclusions

Vapor, A. W1,2, *, Tomaz, C. T1,2, Mendonça, A. G1,2

Results and Discussion

AcknowledgementsThis work was supported by FEDER funds through the POCI - COMPETE 2020 - Operational Programme Competitiveness and

Internationalization in Axis I - Strengthening research, technological development and innovation (Project POCI-01-0145-FEDER-

007491) and National Funds by FCT - Foundation for Science and Technology (PEst-C/SAU/UID/Multi/0709/2014). Vapor, A. W.,

thanks to CICS, MESCTI, INAGBE-Angola and SwissDock. Docking web service based on EADock DSS.

References[1] L. Xie, R. L. Wehling, O. Ciftci, Y. Zhang, Food Research International, 102(2017) 195-202.

[2] T.T.K. Le, D. H. Nguyen, A. T. Vu, T. Ruethers, A. C. Taki, A. L. Lopata, Pediatric Allergy Immunology, 30(2019) 348-355.

[3] A. Grosdidier, V. Zoete, and O. Michielin, Journal of Computational Chemistry, 32(2011) 2149–2159.

1 Department of Chemistry, University of Beira Interior, 6201-001 Covilhã, Portugal2 CICS-UBI - Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal *a.walter.vapor@ubi.pt

+ =Phenolic

compoundOVA Complex OVA+Phen.

Compound 25ºC, 37ºC, 45ºC, 55ºCATR - FTIRCircular Dichroism Fluorescence

Docking [3]

✓ All phenolic compounds bound to OVA and changed its secondary and tertiary structure .

✓ Docking studies showed that TA was the compound that established interactions closer to the OVA epitopes thus avoiding the IgE

binding.

✓ Therefore, the phenolic compounds can be used as a strategy for reducing egg allergy in foods.

1. CD and ATR - FTIR experiments demonstrated changes in the secondary structure of OVA (Fig. 1-2);

2. Fluorescence studies (Fig. 3) suggest that the interactions are electrostatic and thermodynamically favorable (∆G<0);

3. Docking showed that phenolic compounds (Tannic acid in Fig. 4) can interact directly with OVA epitopes or with its neighbors.

TA

Epitope

387 nm

389 nm