Influence of roasting on the chemopreventive potential of in vitro fermented almonds in LT97 colon adenoma cells

Abstract

The consumption of almonds may contribute to the prevention of colon cancer due to their unique composition of health promoting compounds. Since almonds are often consumed roasted, the impact of different roasting (R) conditions (R1 = 139.2 °C/25 min, R2 = 161.5 °C/20 min and R3 = 170.8 °C/15 min) on chemopreventive effects of in vitro-fermented almonds was analysed in LT97 colon adenoma cells. Fermentation supernatants (FS) of raw and roasted almonds had no genotoxic effects. FS obtained from raw or mildly roasted almonds (R1) significantly increased mRNA levels of CAT (4.6-fold), SOD2 (5.6-fold) and GSTP1 (3.9-fold) but not of GPx1. FS of almonds significantly reduced the growth of LT97 cells in a time- and dose-dependent manner. Treatment with 5% almonds FS increased the number of early apoptotic cells (17.4%, on average) and caspase-3 activity (4.9-fold, on average). The results indicate a chemopreventive potential of in vitro-fermented almonds which is largely independent of the roasting process.

Keywords:

• Almonds
• apoptosis
• colon cancer
• dietary fibre

Acknowledgements

The authors thank the Probat-Werke von Gimborn Maschinenfabrik GmbH for roasting the nuts, especially Thomas Koziorowski and Thomas Elshoff. The authors express their gratitude to Gudrun Steinmetzer for her excellent technical assistance. The authors also thank Dr. Ulrich Schäfer for proofreading of the manuscript and Anna Mittag for supporting the MTT assay experiments.

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Funding

This IGF project (AiF 16642 BR) of the FEI (Research Association of the German Food Industry) was supported via AiF (German Federation of Industrial Research Associations) within the programme for promoting the Industrial Collective Research (IGF) of the German Ministry of Economic Affairs and Energy (BMWi), based on a resolution of the German Parliament. The authors would like to thank Nucis e.V. Germany for funding.