Extraction and Stability of Pigment from Hypericum japonicum

Objective:To investigate extraction methods of pigment from Hypericum japonicum by different solvents,and investigate effects of different factors on stability of pigment.Method: Pigment was extracted with 6 different solvents,stability of pigment was tested with pH,temperature,light,reducing agents and oxidants.Result: Extraction effect of pigment was optimum by ultrasonic extraction 10 min with 95% ethanol at 30 ℃,These pigment was unstable in light,strong acidity and alkaline,metal ions of Mg2+,Al3+ and other conditions.Food additives,reducing agents and oxidants had little effect on stability of pigment.Conclusion: These pigment had good stability,but it must prevent pigment using in light and avoid acidity and alkaline condition.Pigment from H.japonicum could be used as a good resource of natural plant pigment.