Effects of genotype and environment on steryl ferulates in wheat and rye in the HEALTHGRAIN diversity screen

The effects of genetic and environmental factors on the content and composition of steryl ferulates in wheat and rye were studied. The wheat and rye genotypes were grown at the same location in Hungary over three consecutive years (28 genotypes) or at four different locations across Europe during a single year (12 genotypes). The steryl ferulates were analyzed using HPLC. The genotype and growing location significantly affected the content and composition of wheat steryl ferulates, whereas the year of growth did not result in considerable variation. Less variation was observed in rye, due to fewer genotypes. Campestanyl and sitostanyl ferulates were the main species in both cereals. Knowledge of the natural variation in steryl ferulates and other bioactive compounds allows cultivators and plant breeders to select genotypes with high, stable levels of beneficial compounds. Thus, it is possible to enhance the intake of health-promoting compounds from natural sources.

Lipophilic and hydrophilic antioxidants and their antioxidant activities in purple rice bran

Purple rice bran was separated and collected at two different milling periods, resulting in two bran (outer and inner layer) fractions. The distribution of lipophilic and hydrophilic antioxidants and their antioxidant activities in the two fractions were studied. The bran fractions were extracted with hexane followed by methanol to obtain lipophilic and hydrophilic extracts, respectively. The total phenolic content and free radical scavenging activity of the extracts were determined and compared. The lipophilic extract from the outer bran fraction (OBF) exhibited a lower level of total tocols and gamma-tocols, compared with the inner bran fraction (IBF), while the levels of gamma-oryzanol in both fractions were not different. However, the lipophilic phenolic content and free radial scavenging activity of the OBF were 6.0 microg catechin equivalent (CE)/g and 5.6 micromol trolox equivalent (TE)/g and higher than those of the IBF, respectively. For the hydrophilic extracts, the level of anthocyanins in the IBF (29.0 mg/g) was 8 times higher than that in the OBF. Also, the hydrophilic phenolic content and free radical scavenging activity of the IBF were 489.1 microg CE/g and 433.6 micromol TE/g, respectively, while they were 113.9 microg CE/g and 78.2 micromol TE/g in the OBF. Both hydrophilic extracts showed significantly higher phenolic content and free radical scavenging activity than any lipophilic extract. The results of this study indicated that the activity of purple rice bran hydrophilic antioxidants was much greater than that of its lipophilic antioxidants and anthocyanins and gamma-tocols largely located in the inner portion of purple rice bran.