Grapefruit Seed Extract comes from the seed, pulp and white membrane of the grapefruit and is in a base of glycerin.
Here's a quick and easy recipe for an all purpose cleaner: Just add 30-40 drops of GSE to a 32 oz sprayer bottle filled with water. Add a few drops of a citrus essential oil (or pine, lavender . . . pick your favorite!) and shake well.
For external use only.