High
efficiency preparation ofstandard
gradeγ-tocopherol
in plant-scale and itsantioxidant
activity
Yaping Li, Linshang Zhang, Zhide Wang, Yanlan Bi*, Dan Peng
College
of Food Science and Engineering,
Henan University of Technology,
Zhengzhou 450001, China
*Corresponding author. E-mail: bylzry@126.com, Tel/Fax:
+86-0371-67756022
Abstract:Natural
standard grade γ-tocopherol are of
great interest due to its good antioxidant activity and special
pharmacological functions. This study separated and purified
γ-tocopherol from mixed tocopherols using eco-friendly and
low toxicity solvents.
0.28
g γ-tocopherol was obtained per performance with a purity of 98.89 ±
0.68% and a recovery yield of 93.23 ± 0.89%. The purification
conditions were as follows: elution solvent n-hexane/ethyl acetate
94.5:5.5 (v/v), sample load size 0.5 g, a column height to diameter
ratio of 16:1 and an elution rate of 2 mL/min. The purity and structure
of γ-tocopherol was confirmed by HPLC, GC/MS and NMR. The adsorption
isotherm of γ-tocopherol on silica gel (200-300 mesh) fitted the
Langmuir isotherm model well. The antioxidant activity analysis showed
that γ-tocopherol had the strongest antioxidant activity followed by
δ-tocopherol and α-tocopherol. This study provides an economically
attractive solution for the production of natural standard grade
γ-tocopherol.
Key words: standard grade
γ-tocopherol; low toxicity solvents; purification; silica gel column
chromatography; antioxidant activity