Adrenocortical cells were prepared from rats maintained on essential fatty acid-deficient diets and control litter mates. Cells from control rats had high concentrations of essential fatty acids in the cholesteryl ester fraction of which approximately 22% was arachidonate. In contrast, cells from EFA-deficient rats had only 2.5% arachidonate in the cholesteryl esters, even though the total este...

The product YkoN of the gene of unknown function, ykoN, of Bacillus subtilis Marburg has the pentapeptide lipase/esterase motif (Gly-X-Ser-X-Gly), and thus YkoN is expected to have a lipase or esterase activity. To characterize the expected enzyme activity the plasmid having a modified ykoN that include the sequence for His(x6) tag at its C-terminus of YkoN, which has 373 amino acid residues, w...

Several approaches were used to test the hypothesis proposing a role for acyl-CoA esters in nutrient-induced insulin release (Prentki, M., and Matschinsky, F. M. (1987) Physiol. Rev. 67, 1185-1248; Corkey, B. E., Glennon, M. C., Chen, K. S., Deeney, J. T., Matschinsky, F. M., and Prentki, M. (1989) J. Biol. Chem. 264, 21608-21612). Exogenous saturated long chain fatty acids markedly potentiated...

Peroxisomes play a major role in human cellular lipid metabolism, including the beta-oxidation of fatty acids. The most frequent peroxisomal disorder is X-linked adrenoleukodystrophy (X-ALD), which is caused by mutations in the ABCD1 gene. The protein involved, called ABCD1, or alternatively ALDP, is a member of the ATP-binding-cassette (ABC) transporter family and is located in the peroxisomal...

Biodiesel, defined as the monoalkyl esters of vegetable oils and animal fats, is an alternative to conventional petroleum-based diesel fuel. Biodiesel has been prepared from numerous common vegetable oils or fats as well as new or less common feedstocks. Major issues facing biodiesel include several technical aspects such as cold flow and oxidative stability as well as availability of sufficien...

In this work, mixed-mode silica particles functionalized with octyl and sulfonic acid groups was conveniently prepared by co-bonding a mixture of n-octyltriethoxysilane and 3-mercaptopropyltriethoxysilane and then oxidized with hydrogen peroxide. Candida rugosa lipase (CRL) was immobilized on the mixed-mode silica particles via hydrophobic and strong cation-exchange interaction. The resulting i...

Biodiesel, an alternative fuel derived from lipid feedstocks, such as vegetable oil or animal fat, is mainly composed of saturated and unsaturated fatty acid alkyl esters. Fuel suppliers, terminal operators, and users are becoming more concerned with monitoring and maintaining good biodiesel fuel quality with respect to oxidative degradation during storage. The oil stability index (OSI), a para...

The metabolism of lipids in the ischemic liver has been examined in the attempt to define the cause of the previously described loss of phospholipid and to determine whether additional alterations occur that may be related to the disturbances in membrane function. With 3 hr of ischemia, 30% of the cellular phospholipid was lost when measured either as phosphate in a lipid extract of the whole l...

To examine the biochemical metabolism of aroma volatiles derived from fatty acids, pear fruits were incubated in vitro with metabolic precursors of these compounds. Aroma volatiles, especially esters, were significantly increased, both qualitatively and quantitatively, in pear fruits fed on fatty acid metabolic precursors. Cultivars having different flavor characteristics had distinctly differe...

Assessment of free fatty acid (FFA) concentration and isotopic enrichment is useful for studies of FFA kinetics in vivo. A new procedure to recover the major FFA from plasma for concentration and isotopic enrichment measurements is described and validated. The procedure involves extraction of plasma lipids with hexane, methylation with iodomethane (CH(3)I) to form fatty acid methyl esters (FAME...