ר' יצחק בן מלכי צדק

Isaac ben Melchizedek, was a rabbinic scholar from Siponto, Italy, and one of the first medieval scholars to have composed a commentary on the Mishnah, of which only his commentary on Seder Zera'im survives. Elements of the Mishnaic order of Taharot are also cited in his name by the Tosafists, but the complete work is no longer extant.