Perilla oil is obtaine from the seeds of perennial herbs of the genus Perilla, usually Perilla frutescens. The seeds contain 35 to 45 percent oil which is obtained by pressing. Perilla oil is used along with synthetic resins in the production of varnishes. Perilla oil dries in less time than linseed oil and on drying forms a film that is harder and yellows more than that formed by linseed oil. The paint and varnish industry accounts for the largest usage. Perilla oil also is important in the manufacture of printing inks and linoleum. In parts of Asia, perilla oil is used as an edible oil that is valued more for its medicinal benefit than its flavor. Perilla oil is a very rich source of the omega-3 fatty acid alpha-linolenic acid (ALA). About 50 to 60% of the oil consists of ALA.