Effectiveness of different depuration procedures in removing reagents interference on in vitro digested strawberry extracts for reliable antioxidant determinations

Article type: Research Article

Authors: Cervantes, Lucía^{a; b} | Martínez-Ferri, Elsa^a | Carrera, Marta^a | Soria, Carmen^a | Ariza, María Teresa^{a; *}

Affiliations: [a] Instituto Andaluz de Investigación y Formación Agraria y Pesquera (IFAPA), Consejería de Agricultura, Pesca y Desarrollo Rural. Junta de Andalucía. IFAPA Centro de Málaga, Churriana, Málaga, Spain | [b] Universidad de Málaga, Andalucía Tech, Facultad de Ciencias, Málaga, Spain

Correspondence: [*] Corresponding author: María Teresa Ariza, Instituto Andaluz de Investigación y Formación Agraria y Pesquera (IFAPA), Consejería de Agricultura, Pesca y Desarrollo Rural. Junta de Andalucía. IFAPA Centro de Málaga, Cortijo de la Cruz s/n, 29140, Churriana, Málaga, Spain. Tel.: +34 671 532 798; Fax: +34 951 036 227; E-mail: mariat.ariza@juntadeandalucia.es.

Abstract: BACKGROUND:Healthy benefits associated with strawberries consumption are mostly related to their antioxidant composition, mainly polyphenols. Quality assessment on fresh fruits is commonly done by spectrophotometric methods, but intake and digestion may alter their composition and healthy properties. To asses antioxidants bioavailability at different gastrointestinal-tract levels, in vitro digestion (IvD) simulations are used but reagents involved in may interfere in antioxidant determinations despite depuration procedures are employed. OBJECTIVE:To test the magnitude of reagents interference in IvD approaches and the effectiveness of different depuration procedures for reliable antioxidant quantifications on strawberries. METHODS:IvD assays were done with water and strawberry samples to obtain digested fractions (gastric and intestinal). After passing-through hydrophilic cotton, digested extracts were subjected to different depuration procedures: centrifugation, Sep-Pack and 0.45 μm nylon-filter. Antioxidant content and capacity were evaluated spectrophotometrically. RESULTS:IvD reagents interfered in all antioxidant determinations, especially in the intestinal fractions. Depuration procedures differed in their effectiveness for reagents removal and in their antioxidant retrieval efficiency, with hydrophilic cotton displaying better recovery efficiency. CONCLUSIONS:Reagents interference should be considered for antioxidant content and capacity determinations after IvD but, for reliable estimations of healthy compounds of food matrices, depuration methods should prioritize antioxidant recovery over reagents removal.

Keywords: Bioavailability, biliar salts, pepsin, gastrointestinal digestion, phenolic compounds, spectrophotometric

DOI: 10.3233/JBR-190385

Journal: Journal of Berry Research, vol. 9, no. 3, pp. 473-481, 2019