Tl. Xue et al., A SMALL-SCALE HPLC METHOD FOR DETERMINATION OF ALPHA-TOCOPHEROL IN FRESH PLANT-TISSUE, Agribiological research, 50(3), 1997, pp. 265-270
This paper presents an high-performance liquid chromatographic (HPLC)
method for the determining of alpha-tocopherol in small samples of fre
sh plant material. Ryegrass was used as the test material. The samples
of 5-100 mg are saponified for 30 min at 60 degrees C. After evaporat
ing the n-hexane extract of the unsaponifiables and dissolving the res
idue in n-hexane, the sample is ready for the HPLC analysis. The HPLC
system involves an amino column, n-hexane-isopropanol (99:1) flowing a
t the rate of 2 ml/min as the mobile phase and a fluorescence detector
. The recovery of alpha-tocopherol added to ryegrass samples was 110 %
when the quantification was based on an alpha-tocopherol standard run
through the whole sample preparation procedure. The variation in the
alpha-tocopherol contents was 11 % (coefficient of variation CV %) whe
n 18 samples ranging 5-100 mg were analysed within one day. The day-to
-day variation was only 4.6 % when samples of 50-100 mg were analysed.
The results confirm that this simple, rapid and sensitive method is s
uitable both for routine analysis of fresh plant tissues and for plant
physiological studies where live plants are to be monitored by repeat
ed sampling.