One-dimensional And Two-dimensional Liquid Chromatography Analysis The Loss And Isomerization In The Extraction Of Astaxanthin From Phaffia Rhodozyma

Astaxanthin is a carotenoid belonging to the lutein family.Compared with other carotenoids,astaxanthin has stronger antioxidant capacity and other biological activities,such as anti-inflammation,anti-diabetes,anti-cancer and improving immunity.Phaffia rhodozyma is an important source of natural astaxanthin with a broad prospect in industrial astaxanthin production.High performance liquid chromatography(HPLC)is an important analysis method for astaxanthin.In this paper,the extraction loss of astaxanthin in the extraction process was analyzed by high performance liquid chromatography(HPLC).An on-line two-dimensional liquid chromatography method for all-trans-astaxanthins was established.The effects of extraction conditions on all-trans-astaxanthins were investigated.At the same time,the effect of extraction conditions on astaxanthin isomerization of Phaffia rhodozyma was also analyzed.The main experimental results are as follows:(1)The standard curve was established Y=861648X+1992.5.The intra-day precision ranges from 0.13%to 1.45%,the intra-day precision ranges from 1.14%to 1.67%,and the recovery of standard addition ranges from 95.1 1%to 100.76%.(2)The loss of astaxanthin extraction from Phaffia rhodozyma was studied by HPLC.It was found that in the process of extracting astaxanthin from Phaffia rhodozyma by DMSO,the extraction rate of acetone was 95.34%,petroleum ether was 96.19%,and ethyl acetate was 88.01%.The results showed that ethyl acetate extraction was the main step leading to astaxanthin loss during extraction from Phaffia rhodozyma.(3)The first dimensional and seconed dimensional condition was investigated.The 2DLC method was validated in terms of linearity,precision and recovery.The precision of the method was between 0.32%and 1.14%,and the accuracy was between 98.63%and 106.13%.(4)The stability of all-trans-astaxanthin was significantly affected by day light,ultrasound and heating.Heating treatment had the greatest effect on the stability of all-trans-astaxanthin,and heat treatment transformed all-trans-astaxanthin into other geometric isomers,especially 13-cis-astaxanthin.A one-dimensional and a two-dimensional liquid chromatographic method for the determination of astaxanthin and its isomerization in Phaffia rhodozyma were established.It was found that ethyl acetate extraction was the key factor affecting the loss of astaxanthin in the extraction process,and heating was the main reason for the conversion the all-trans-astaxanthin to cis-isomers.The results have important reference value for the extraction and utilization of astaxanthin from Phaffia rhodozyma.