Characterization of anthocyanin and nonanthocyanidin phenolic compounds and/or their biosynthesis pathway in red-fleshed 'Kanghong' grape berries and their wine

Abstract

This study determined the composition and content of anthocyanin compounds in red-fleshed 'Kanghong' (KH) berries and wine and revealed the anthocyanin biosynthesis pathway in KH flesh. The 41 anthocyanin compounds detected primarily accumulated in KH skin, followed by flesh and seeds. Anthocyanin compounds with a single glucoside, particularly malvidin-3-O-glucoside, were the most abundant components in KH berries. The percentage of anthocyanin compounds was altered in KH flesh compared to KH skin. KH berries and their wine contained a much higher anthocyanin content than Cabernet Sauvignon (CS) wine. Additionally, a total of 48 differentially accumulated nonanthocyanin phenolic compounds and 2104 differentially expressed genes between KH and CS flesh were identified, and their association analysis indicated that the metabolic flux of phenolic compounds in the phenylpropanoid pathway was promoted in KH flesh. Therefore, this work elucidated the accumulation characteristics of anthocyanins in KH berries and provided the mechanism underlying grape flesh coloration.

Keywords: Anthocyanin compounds; Phenylpropanoid pathway; RNA-seq; Red-fleshed grape; Targeted metabolome; Wine.