Determination of vitamin e amount in some grape seeds in Turkey by HPLC

In this study, HPLC method was optimized by using C-18 column in the quantitative and qualitativedetermination of tocopherols in grape seeds. Firstly, the seeds were dried, weighed to3.0000 ± 0.0002 gram and extracted for one hour with 25 ml hexane after grinded (25 x 2). Eachextract was filtered with blue band fitler paper and completed to 50 ml with hexane. Then, it wasanalyzed under the optimized conditions.α, δ, ve γ-tocopherols were separated in 9 minutes in C-18 column by using 99.99 % n-hexane and0.01 % isopropyl alcohol at 295 nm with UV_VIS detector. The measurements were taken at 295 nmwavelength when flowrate was adjusted to 2 ml / min.In the separation of tocopherols µ-porasil column was also tried, however it was investigated thatoptimized conditions for C-18 column did not work. The desired separation was performed with99.92 % n-hexane and 0.08 % isopropyl alcohol as mobile phases when 1 ml / min flowrate was used.The samples were analyzed with HPLC under the optimized conditions. The tocopherol amounts in21 different grape seeds were found to range between 2-40 µg / g.Keywords: HPLC, determination of tocopherols ,vitamin E , extraction of tocopherols, grape seed.X