Nitrate appears to be the urinary component inhibiting oxalate oxidase.
D006801:Humans; D009566:Nitrates / Q000652:urine*; D017942:Nitric Acid; D010088:Oxidoreductases / Q000037:antagonists & inhibitors* / Q000652:urine; D010944:Plants / Q000201:enzymology
D009566:Nitrates; D017942:Nitric Acid; D010088:Oxidoreductases; C020598:oxalate oxidase