Study on extraction and characterization of red pigment from Loropetalum chinense var.rubrum

Physico-chemical properties and extractions of the red pigment in leafages of Loropetalum chinense var.rubrums were investigated.Results showed that good yield of pigment could be obtained by 80% C_2H_5OH solution of pH1 at 80℃ for 40min with the solid-liquid ratio(1∶40 g/mL.)The Loropetalum chinense var.rubrums red pigment is classified to anthocyanins,for which pH had significant effect on the tone of pigment.The pigment is stable to heat under 60℃.Under sunlight,degradation of the pigment could be accelerated,but regardless of ultraviolet light.Metallic ions Na~+、Ca~(2+)、Zn~(2+) 、A~(3+)、Cu~(2+)had no effect on the tone of pigment,but Fe~(3+)、Pb~(2+) had severe disadvantageous effect.This kind of pigment has better endurance capability against redcing agent,but it has less resistance capability against oxidizing agent.Addition of glucose,sucrose had no effect on the pigment.