Variation In Tocopherol and Tocotrienol Contents In Some Koean Adlay (Coix lacryma jobi L.) Varieties

Vitamin E is a well known antioxidant compound commonly found in seeds of cereals crops. To quantify vitamin E contents in adlay (Coix lacryma jobi L.) seeds, 8 different varieties generally cultivated in Korea were selected and the contents of vitamin E isomers: alpha (a)-, beta (b)-, gamma (g)-, and delta (d)- tocopherols (T) and tocotrienols (T3) in both polished and unpolished seeds were measured by using a gas chromatography. In the case of unpolished seeds, the average contents of aT, bT, gT, dT and total T were 0.18, 0.10, 1.47, 0.19 and 1.95 mg/100g, respectively and those for aT3, gT3, dT3 and total T3 were 0.20, 1.42, 0.17 and 1.79 mg/100g, respectively. Among 8 tested varieties, unpolished seeds of var. Yulmo-1 exhibited highest total vit E content (4.73 mg/100g). In the case of polished seeds, the average contents of aT, gT, dT and total T were 0.13, 1.63, 0.19 and 1.95 mg/100g, respectively and aT3, gT3, dT3 and total T3 were 0.26, 1.85, 0.21 and 2.33 mg/100g, respectively. Highest vit E content could be observed in var. Johyeon (5.13 mg/100g), which showed highest gT, dT, and aT3 contents compared to other varieties. Unlike the unpolished case, no bT could be observed in polished adlay seeds in all tested varieties under our experimental conditions. In most varieties no significant difference in total vit E content could be observed between polished and unpolished seeds, while var. Johyeon showed significantly lower total vit E content in unpolished seeds (3.17 mg/100g) compared to polished seeds (5.13 mg/100g).