 Such conditions include hemorrhagic shock, myocardial infarction (heart attack), and stroke.One of the first substances that was reported to produce an oxygen diffusion-enhancing effect was crocetin, a carotenoid that occurs naturally in plants such as "crocus sativus", and is related to another carotenoid, saffron.Saffron has been used culturally (e.g., as a dye) and medicinally since ancient times.