Transcrocetin (trans-Crocetin), a saffron metabolite originating from the crocin apocarotenoids, has been shown to exert strong NMDA receptor affinity and is thought to be responsible for the CNS activity of saffron.To ensure unchanged viability of Caco-2 cells throughout the transport experiments, cellular mitochondrial dehydrogenase activity of Caco-2 cells is measured by MTT assay after a 24 h incubation period with the test compounds: Hydroalcoholic saffron extract saffron extract (SE, 0.5-1 mg/mL) and crocin-1 (250-1000 µM) reveal no negative significant changes in cellular viability. Transcrocetin at 10 µM level does not change viability while higher concentrations (40-160 µM) reduces significantly cellular viability.