{Reference Type}: Journal Article {Title}: Identification of Sarmentosin as a Key Bioactive from Blackcurrants (Ribes nigrum) for Inhibiting Platelet Monoamine Oxidase in Humans. {Author}: Lomiwes D;Günther CS;Bloor SJ;Trower TM;Ngametua N;Kanon AP;Jensen DA;Lo K;Sawyer G;Walker EG;Hedderley D;Cooney JM; {Journal}: J Agric Food Chem {Volume}: 72 {Issue}: 30 {Year}: 2024 Jul 31 {Factor}: 5.895 {DOI}: 10.1021/acs.jafc.4c03802 {Abstract}: Previous clinical studies indicate that monoamine oxidase-B (MAO-B) inhibition by blackcurrants must be predominantly attributed to bioactives other than anthocyanins. In this natural products discovery study, MAO-A/B inhibitory phytochemicals were isolated from blackcurrants, and a double-blind crossover study investigated the efficacy of freeze-dried whole-fruit blackcurrant powder in inhibiting MAO-B compared with blackcurrant juice in healthy adults. Platelet MAO-B inhibition was comparable between powder (89% ± 6) and juice (91% ± 4), and it was positively correlated with MAO-modulated plasma catecholamines, subjective alertness, and reduced mental fatigue, assessed using the Bond-Lader questionnaire. Sarmentosin, a nitrile glycoside, and its hydroxycinnamoyl esters were identified as novel MAO-A/B inhibitors from blackcurrant in vitro, and sarmentosin was demonstrated to inhibit platelet MAO-B activity in vivo. These findings confirm sarmentosin as the primary bioactive for MAO-A/B inhibition in blackcurrants, as well as its bioavailability and stability during freeze-drying, and suggest that consuming blackcurrant powder and juice may positively affect mood in healthy adults.