Turtles are omnivores and enjoy a varied diet of vegetables, fruits, and meats. While eggplants are not toxic to turtles, they are not a preferred or recommended food for them. Eggplants contain solanine and chaconine which can cause gastrointestinal upset in turtles if consumed in large quantities. It is best to stick to foods that are more suitable for turtles, such as leafy greens, vegetables, and small amounts of fruits and protein sources such as insects, worms, or cooked chicken or fish. If you are unsure about what to feed your turtle, it is recommended to consult with a veterinarian or a knowledgeable reptile expert.