Effects of tree age on flavonoids and antioxidant activity in Torreya grandis nuts via integrated metabolome and transcriptome analyses

Abstract

<p> The nuts of <em>Torreya grandis</em> are abundant in flavonoids, providing potential antioxidant activity. Considering that <em>T. grandis</em> can yield nuts for hundreds or thousands of years, effects of tree age on flavonoids and antioxidant activity of <em>T. grandis</em> nuts were targeted in this study for the first time. Results revealed that antioxidant activity and total flavonoid contents in 100- and 1000-years-old <em>T. grandis</em> nuts were much higher compared to 10-years-old <em>T. grandis</em>. The content of 19 flavonoids showed significant correlations with antioxidant activity in 100- and 1000-years-old trees using metabolites profiling. Transcriptome and coexpression analysis indicated that seven genes were associated with aged-related flavonoids biosynthesis. Further analysis showed that abscisic acid and gibberellin might regulate the age-related differential flavonoids accumulation. Our study provides a novel viewpoint that aged <em>T. grandis</em> is likely to present a better source of natural antioxidants and has yet to be examined in other tree models. <br></p>