Effect of simulated gastrointestinal digestion and fermentation on polyphenolic content and bioactivity of brown seaweed phlorotannin-rich extracts.

TY - JOUR

T1 - Effect of simulated gastrointestinal digestion and fermentation on polyphenolic content and bioactivity of brown seaweed phlorotannin-rich extracts.

AU - Corona, Giulia

AU - Coman, Maria Magdalena

AU - GUo, Yuxuan

AU - Hotchkiss, Sarah

AU - Gill, Chris

AU - Yaqoob, Parveen

AU - Spencer, Jeremy P. E.

AU - Rowland, Ian

PY - 2017/8/29

Y1 - 2017/8/29

N2 - Scope: Unlike other classes of polyphenols, there is a lack of knowledge regarding brown seaweed phlorotannins and their bioactivity. We investigated the impact of in vitro gastrointestinal digestion and colonic fermentation on the bioactivity of a seaweed phlorotannin extract from Ascophyllum nodosum and its high molecular weight (HMW) and low molecular weight (LMW) fractions. Methods and Results: The highest phlorotannin and total polyphenol (TP) concentration was observed in the HMW fraction. Antioxidant capacity broadly followed phlorotannin and TP levels, with HMW having the highest activity. Both gastrointestinal digestion (GID) and colonic fermentation (CF) significantly affected phlorotannin and TP levels, and antioxidant capacity of the extract and fractions. Despite this, in HT-29 cells, all GID extracts significantly inhibit cell growth, whereas CF extracts effectively counteracted H2O2 induced DNA damage. Conclusion: Although phlorotannins, TP levels and antioxidant power of the extracts were strongly reduced after in vitro digestion and fermentation, their anti-genotoxic activity and cell growth inhibitory effect in colon HT-29 cells was maintained and enhanced. HMW was the most effective fraction, indicating that the high molecular weight phlorotannins potentially exert a stronger beneficial effect in the colon.© 2017, WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an author produced version of a paper published in Mol. Nutr. Food Res. 2017, uploaded in accordance with the publisher’s self- archiving policy. The final published version (version of record) is available online at the link below. Some minor differences between this version and the final published version may remain. We suggest you refer to the final published version should you wish to cite from it.

AB - Scope: Unlike other classes of polyphenols, there is a lack of knowledge regarding brown seaweed phlorotannins and their bioactivity. We investigated the impact of in vitro gastrointestinal digestion and colonic fermentation on the bioactivity of a seaweed phlorotannin extract from Ascophyllum nodosum and its high molecular weight (HMW) and low molecular weight (LMW) fractions. Methods and Results: The highest phlorotannin and total polyphenol (TP) concentration was observed in the HMW fraction. Antioxidant capacity broadly followed phlorotannin and TP levels, with HMW having the highest activity. Both gastrointestinal digestion (GID) and colonic fermentation (CF) significantly affected phlorotannin and TP levels, and antioxidant capacity of the extract and fractions. Despite this, in HT-29 cells, all GID extracts significantly inhibit cell growth, whereas CF extracts effectively counteracted H2O2 induced DNA damage. Conclusion: Although phlorotannins, TP levels and antioxidant power of the extracts were strongly reduced after in vitro digestion and fermentation, their anti-genotoxic activity and cell growth inhibitory effect in colon HT-29 cells was maintained and enhanced. HMW was the most effective fraction, indicating that the high molecular weight phlorotannins potentially exert a stronger beneficial effect in the colon.© 2017, WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an author produced version of a paper published in Mol. Nutr. Food Res. 2017, uploaded in accordance with the publisher’s self- archiving policy. The final published version (version of record) is available online at the link below. Some minor differences between this version and the final published version may remain. We suggest you refer to the final published version should you wish to cite from it.

U2 - 10.1002/mnfr.201700223

DO - 10.1002/mnfr.201700223

M3 - Article

SN - 1613-4125

JO - Molecular Nutrition and Food Research

JF - Molecular Nutrition and Food Research

ER -