Water is a great solvent. It’s neutral and doesn’t provide any strong positive or negative effects. It just helps components to mix better and to transport active components.
Green Tea Leaf Extract is a great antioxidant often used in Korean skincare products. It contains EGCG - the most effective flavonoid. It makes the skin look fresh, fills it with vitamines, and helps to prevent aging. It also helps to lower inflammation.
Xanthan Gum is used as a thickener or rheology modifier and emulsion stabilizer. It doesn’t provide any notable skin-related effects and is used mostly for formulation purposes. It makes the product’s texture smooth and even. It’s a naturally-derived thickener. Notable fact: it can also be found in the food you eat every day, so it is 100% safe.