https://doi.org/10.17113/ftb.64.03.26.9286

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Assessment of the Potential Impact of Aqueous and Ethanolic Malt Extracts on HepG2 Liver Cells

Diana Santos¹, Maria João Pereira¹, Ângelo Jesus², Rita Ferraz de Oliveira^2,3, Ana Isabel Oliveira² and Cláudia Pinho^2*

¹ESS, Polytechnic of Porto, Rua Dr. António Bernardino de Almeida 400, 4200-072 Porto, Portugal

²REQUIMTE/LAQV, ESS, Polytechnic of Porto, Rua Dr. António Bernardino de Almeida 400, 4200-072 Porto, Portugal

³Center for Health Technology and Services Research at the Associate Laboratory RISE-Health Research Network (CINTESIS@RISE), Department of Education and Psychology, University of Aveiro (UA), Campus Universitário de Santiago, 3810-193 Aveiro, Portugal

Copyright © 2026 This is a Diamond Open Access article published under CC-BY licence. Copyright remains with the authors, who grant third parties the unrestricted right to use, copy, distribute and reproduce the article as long as the original author(s) and source are acknowledged.

Food Technol. Biotechnol. 2026; 64(3).

Article history:

Received: 24 July 2025

Accepted: 25 June 2026

Keywords:

craft beer; malt; antioxidant; metabolic activity; alanine aminotransferase (ALT)

Summary:

Research background. Malt is the second most abundant raw material in beer and the main source of phenolic compounds. However, information on the specific contribution of different types of malt to the biological activity of beer and its effects on liver function remains limited. Therefore, this study aims to evaluate the antioxidant potential and effects on liver function of a Portuguese craft beer (Imperial Stout - IS-N) and the aqueous and ethanolic extracts of malts present in IS-N beer (Carafa III, Caramunich III, Carapils and Pilsner).

Experimental approach. The aqueous and ethanolic extracts of malt were obtained by solid-liquid extraction at a ratio of 1 g of powder to 9 mL of distilled water and 1 g of powder to 10 mL of 95 % (V/V) ethanol solution, respectively. The total phenolic content (TPC) was determined by the Folin–Ciocalteu method, and antioxidant activity was evaluated by ABTS, DPPH, and metal chelating capacity (ferrozine) assays. Cytotoxicity was evaluated in HepG2 cells using the MTT assay after exposing the cells to different concentrations of the samples (1–500 µg/mL) for 24 and 48 hours. Liver function was evaluated by determining alanine aminotransferase (ALT) activity in the cell supernatant.

Results and conclusions. TPC values ranged from (7.12±0.54) mg GAE/g to (28.19±0.53) mg GAE/g, with the aqueous extract of Caramunich III ((23.61±0.61) mg GAE/g) standing out for its high TPC and greater antioxidant capacity (IC50 ABTS=(17.32±0.77) µg/mL; IC50 DPPH=(152.64±9.34) µg/mL). Malt extracts showed no cytotoxicity up to 250 µg/mL, while IS-N beer showed cytotoxicity in ethanolic solvent at 500 µg/mL after 24 hours. IS-N beer induced lower ALT levels compared to single malts, suggesting a possible synergistic effect between its bioactive compounds. Thus, evaluating the biological activity of malts could contribute to the production of beers with a better functional profile and less hepatic impact.

Novelty and scientific contribution. This study breaks new ground by exploring the role of malts in the antioxidant activity and hepatic impact of craft beer, offering new data that could guide the development of beverages with a functional profile that is more beneficial for health.