Kuromanin is a natural anthocyanin found in the fruits of some plants. Technically known as cyanidin 3-O-β-glucopyranoside, this polyphenolic compound scavenges superoxide anion radicals (IC50 = 69 μM) and protects neurons from oxidative stress. Also, kuromanin inhibits the ADP-ribosyl cyclase CD38 (IC50 = 6.3 μM), preventing the metabolism of NAD+ and NADP+.