Deadly nuts - detection of 3-nitropropionic acid in coconuts

The secondary metabolite 3-nitropropionic acid (3-NPA) is produced by certain fungi. The metabolite is a potent toxin which inhibits the citric acid cycle. A medical case from 2021 described a 69-year-old Danish man who ingested 3-nitropropionic acid contaminated coconut water. The man died 26 hours after ingestion. Subsequent analysis identified Apiospora saccharicola as the fungi responsible for synthesising 3-NPA in the coconut. The metabolic pathway for 3-NPA is unknown but is thought to be activated by adverse growth conditions. This study aimed to confirm that Apiospora can produce 3-NPA within coconuts and develop a quick and easy method for detection of 3-NPA in coconut water using 1H NMR. This method can possibly aid in detection of 3-NPA in contaminated groceries, such as coconut water.