Do seeds have antioxidants in them?

Yes

Sesame seeds are loaded with powerful antioxidants: IP-6 (AKA: Phytate; one of the most powerful antioxidants yet found, and one of the most potent natural anti-cancer substances.Sunflower seeds are an Excellent source of vitamin E. Vitamin E is an antioxidant that neutralizes free radicals in the body

Linseed also known as Flaxseed contain Lignan which is a chemical compound found in plants that is a powerful antioxidant. Flaxseed oil contains one of the highest concentration of lignan known

Nuts which are a form of seed have a wide range of antioxidants etc etc