- Phosphodiesterases (PDEs) are essential enzymes for the regulation of pathways mediated
by cyclic adenosine monophosphate (cAMP). Secondary plant compounds like anthocyanins (ACs)
can inhibit PDE activity and, consequently, may be beneficial for lipid metabolism. This study
investigated 18 AC-rich juice extracts and pure reference compounds from red fruits for potential
inhibitory effects on PDE 3B activity. Extracts were obtained through adsorption on Amberlite® XAD
7 resin. Based on this screening, the chokeberry, blueberry, pomegranate, and cranberry extracts
were active, with half maximal inhibitory concentrations (IC50) ranging from 163 ± 3 µg/mL to
180 ± 3 µg/mL. The ACs in these extracts, peonidin-3-glucoside and cyanidin-3-arabinoside, were the
most active single compounds (IC50 = 56 ± 20 µg/mL, 108 ± 6 µg/mL). All extracts comprised high
amounts of phenolic compounds, as determined by the Folin–Ciocalteu assay, ranging from 39.8 ± 1.5
to 73.5 ± 4.8 g gallic acid equivalents (GAE)/100 g extract. Pomegranate and chokeberry extracts
exhibited the largest amounts of polyphenols (72.3 ± 0.7 g GAE/100 g, 70.6 ± 4.1 g GAE/100 g,
respectively). Overall, our results showed that fruit juice extracts and their ACs can inhibit PDE
activity. Any potential health benefits in vivo will be investigated in the future.
