Egfl7 is significantly upregulated in human epithelial tumor tissues, suggesting Egfl7 to be a potential biomarker for human epithelial tumors, especially HCC and breast cancer.

Esters of carboxylic acids including 2-methylhexanoic, 2-methylbutyric, 2,2-dimethyl-4-pentenoic, palmitic, and oleic acids were tested as substrates in methoxide-catalyzed interesterification and transesterification. The aliphatic acid esters participated in the ester-ester interchange upon addition of catalytic sodium methoxide. Their isopropyl esters also produced methyl esters on heating with sodium methoxide. The esters of α-methyl-substituted acids did not participate in the ester-ester interchange. Their isopropyl esters did not react with methoxide to produce methyl esters. However, upon addition of methanol with sodium methoxide, their methyl esters were produced. These results indicate that the first step in interesterification is possibly that methoxide abstracts the α-hydrogen of an ester to form a carbanion. Interesterification is then likely completed via a Claisen condensation mechanism involving the β-keto ester anion as the active intermediate. The β-keto ester anion contains positively charged ketone and acyl carbons that are active sites for nucleophilic attack by anions such as methoxide and glycerinate, which would produce a methyl ester or rearrange acyls randomly. On the other hand, transesterification is a nucleophilic substitution by methoxide at the acyl carbon in the presence of methanol.Chemical interesterification rearranges the distribution of FA in TG. This rearrangement changes the TG composition, and therefore the physical properties of the oils, and does not lead to the formation of trans FA.Interesterification can occur without catalysts at very high temperatures, such as 250°C, or catalytically under milder conditions, such as 60°C. Many compounds have been patented as interesterification catalysts including metal salts, alkali hydroxide, alkoxide (alkylates), and alkali metals (1-3). Sodium methoxide is the most commonly used catalyst for chemical interesterification. The reaction is commonly divided into three periods: induction, interchange, and completion. During the induction period (ranging from seconds to minutes), sodium methoxide reacts with glycerides to produce an intermediate commonly referred to as the "real catalyst" (1); no interchange of acyl groups takes place during this period. Although the existence of this real catalyst is not doubted by those skilled in the art, experimental evidence revealing the identity or structure of the catalytic species is still lacking. Once the real catalyst is formed, the interchange period of the reaction begins. Acyl groups continue to interchange until thermodynamic equilibrium is reached and no further net change in the distribution of FA occurs. At this point, the reaction reaches the third period, completion, which is usually terminated out by quenching with water to destroy the real catalyst.Two reaction mechanisms have been proposed for interesterification. Weiss et al. (4) suggested that interesterification was initiated when methoxide abstracted the α-hydrogen of an ester to form an enolate anion (α-carbanion ester) tha...

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In vivo radiotracer experiments using [1-(14C)]acetate as the precursor were conducted to investigate the biosynthesis of vernolic acid (12, 13-epoxy-cis-9-octadecenoic acid) in the seeds of Vernonia galamensis. The acetate precursor radioactively labeled vernolate in phosphatidylcholine (PC), diacylglycerol, and triacylglycerol. Time-course kinetics of the incorporation of the radioactive tracer indicated that vernolate is synthesized while the acyl moiety is esterified to PC. Pulse-chase experiments provided additional supporting evidence that vernolate is synthesized while esterified to PC. These results are consistent with the hypothesis that linoleoyl PC is the precursor of vernoleoyl-PC. Subsequently, vernolate is quickly moved from the PC pool to the triacylglycerol pool, where it accumulates.