PREPROCESSING METHOD FOR OPTIMUM EXTRACTION OF PIGMENT INGREDIENT CONTAINING SHIKONIN OF A LITHOSPERMUM ETYTHROHIZON

摘要

A method for pretreating Lithospermum erythrorhizonis provided to maximize extraction yield of pigment ingredients containing shikonin by minimizing changes under conditions of temperature and light, increase stability of pigments, minimize influence of metal ions, and reduce distinct smell of Lithospermum erythrorhizon. A method for pretreating Lithospermum erythrorhizon comprises the steps of: (a) washing dried Lithospermum erythrorhizon; (b) dipping the washed Lithospermum erythrorhizon in citric acid solution containing 0.1-0.3% of citric acid based on the weight of Lithospermum erythrorhizon for 20-24 hours; and (c) washing and drying the dipped Lithospermum erythrorhizon for 4-10 hours, and optionally cutting the dried Lithospermum erythrorhizon to 2-6 cm.