摘要
从紫甘蓝叶片中提取分离紫甘蓝色素,研究紫甘蓝色素在不同条件下的稳定性及抑菌性。结果表明:紫甘蓝色素在pH2的酸性水溶液中呈现原植物具有的紫红色,稳定性较好;随着pH值的增高,紫甘蓝色素发生向蓝色再到绿色的转变,且最大吸收波长发生红移。紫甘蓝色素自然光照射2d后,色素的保存率在91%以上,自然光照射6d后,色素的保存率仍在79%以上;紫甘蓝色素70℃以下加热2h,色素的保存率在97%以上,90℃加热2h,色素的保存率仍在90%以上,这说明紫甘蓝色素对光照和加热均有一定耐受性。紫甘蓝色素对钠、钾、钙、镁等金属离子和氧气均稳定,但铁离子会使其变质。在紫甘蓝色素溶液的质量浓度为10mg/100mL时,对金黄色葡萄球菌和枯草芽孢杆菌的生长就具有极显著的抑制作用,随着色素质量浓度的提高,抑制作用愈来愈大,但未见紫甘蓝色素对大肠杆菌生长有抑制效果。
The pigment in the leaves of purple cabbage was extracted from, and its stability and antibacterial activity were measured by spectrophotometry. The pigment extracted looked carmine, the original color of purple cabbage, and was stable when exposed to acidic aqueous solution at pH 2. As pH increased, its color gradually changed from carmine to blue, then to green, with the occurrence of a red-shift of maximum absorption wavelength. The preservation rates of the pigment after illumination under natural light for 2 and 6 days were more than 91% and more than 79%, respectively, and the value after 2 hours of heating at temperatures below 70 ℃ was still more than 90%, suggesting that the pigment has good tolerance to light and heating. In the presences of some metal ions including sodium, potassium, calcium, magnesium or oxygen, the pigment was stable, whereas the attendance of iron would deteriorate it. The pigment had significant concentration-dependent inhibitory effect against Staphyloccus aureus and Bacillus subtilis at a concentration of 10 mg/100 mL, but no anti-E. coli effect was observed.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2010年第23期32-35,共4页
Food Science
基金
淮海工学院自然科学基金项目(Z2007036)
关键词
紫甘蓝
色素
稳定性
抑菌性
purple cabbage
pigment
stability
bacteriostasis
