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Total ether-extractable phenolic compounds in Span rapeseed constituted 1.5 and 0.2% of dehulled and diffusion-extracted flours, respectively. The principal phenolic constituents tentatively identified in de-hulled flour were p-hydroxybenzoic, trans-cinnamic and sinapic acids while small quantities of p-coumaric, ferulic, caffeic, chlorogenic and two unknown acids were also detected by gas-liquid chromatography. Five phenolic acids which occurred in the ester form in the dehulled flour also occurred in the diffusion extracted flour. The sinapic acid ester constituted 85% of the phenolic compounds in the diffusion extracted flour and, because of its low taste threshold, may contribute adverse flavors to rapeseed food products.

Biotin-deficient rat liver mitochondria showed decreased phosphorylation efficiency as well as poor respiratory control as compared to normal rat liver mitochondria when pyruvate or α-ketoglutarate was oxidized. The respiratory rate, ADP/O and respiratory control ratios were reduced when the deficient mitochondria oxidized dl -β-hydroxybutyrate. This is related to the drastic reduction in d (−) β-hydroxybutyrate dehydrogenase in the deficient mitochondria. There was no difference between biotin-deficient and normal rat liver mitochondria in any of the parameters referred to above when succinate was oxidized. The basal ATPase activity of deficient mitochondria was higher than that of normal mitochondria. As the in vitro addition of albumin did not improve the efficiency of coupling, endogenously released free fatty acids do not seem to be involved. It is suggested that changes in the phospholipid component of the mitochondrial membrane might be responsible for the observed loose coupling.