In one aspect, the present invention provides a method for preparing a polysaccharide extract of microalgae. In another aspect, the present invention provides a polysaccharide extract of microalgae prepared by said method, in particular, a water soluble polysaccharide extract of microalgae. The polysaccharide extract of the present invention exhibits whitening activity, anti-oxidant activity, activity of promoting cell growth, anti-aging activity, and anti-inflammatory activity, and can be used in a cosmetic composition or a pharmaceutical composition.在一方面,本發明提供一種用於製備微藻多醣萃取物之方法。另一方面,本發明提供以所述方法製備的微藻多醣萃取物,特別是一種水溶性微藻多醣萃取物。本發明之微藻多醣萃取物具有美白、抗氧化、促進細胞生長、抗老化及抗發炎之活性,可用於化妝品組合物或醫藥組合物。無
