Odorant volatile sulfur compounds in cat urine: occurrence of (+/−)‐3,7‐dimethyloct‐3‐sulfanyl‐6‐en‐1‐ol and its cysteine conjugate precursor

Abstract

ABSTRACT Cat urine from female, male, spayed female or neutered male cats was fermented with an undefined soil microflora broth to create a typical cat urine malodour. This fermented urine was extracted and analysed by a gas chromatograph–mass spectrometer coupled to an olfactory port. Sulfur compounds are the major contributors to cat urine odour, the key odorants being 4‐methyl‐4‐sulfanyl‐pentan‐2‐one, 3‐methyl‐3‐sulfanyl‐butan‐1‐ol and 3‐methyl‐3‐sulfanyl‐1‐butyl formate. Other compounds contributing to aged cat urine odour are mainly indole and para ‐cresol. In addition to felinine, a cysteine‐ S ‐conjugate precursor of 3‐methyl‐3‐sulfanyl‐butan‐1‐ol, the occurrence of S ‐(1‐hydroxy‐3,7‐dimethyl‐6‐octen‐3‐yl)cysteine (1.4 mg/L (±0.2) on average in male cats is described for the first time. Its concentration is proportional to that of felinine. Copyright © 2014 John Wiley & Sons, Ltd.