with means of 0.4% and 0.6%, respectively, and may be an under-appreciated marker for seafood intake. Consuming a standardized portion, 70 g ( 2. 5 oz), of wild freshwater fish contributes
only small amounts of BCFA, 2. 5–24. 2 mg, to the American diet,
while it adds surprisingly high amounts of EPA + DHA (107 mg
to 558 mg).
A Vernonia diacylglycerol
acyltransferase can increase
renewable oil production
Hatanaka, T., et al ., J. Agric. Food Chem. 64: 7188–7194, 2016,
Increasing the production of plant oils such as soybean oil
as a renewable resource for food and fuel is valuable. Successful
breeding for higher oil levels in soybean, however, usually results
in reduced protein, a second valuable seed component. This study
shows that by manipulating a highly active acyl-CoA:diacylglyc-erol acyltransferase (DGAT) the hydrocarbon flux to oil in oilseeds can be increased without reducing the protein component.
Compared to other plant DGATs, a DGAT from Vernonia galamen-sis (Vg DGAT1A) produces much higher oil synthesis and accumulation activity in yeast, insect cells, and soybean. Soybean lines
expressing VgDGAT1A show a 4% increase in oil content without reductions in seed protein contents or yield per unit land area.
Incorporation of this trait into 50% of soybeans worldwide could
result in an increase of 850 million kg oil/year without new land
use or inputs and be worth ∼US $1 billion/year at 2012 production
and market prices.
Enzymatic synthesis of steryl ferulates
Schär, A. and L. Nyström, Eur. J. Lipid Sci. Technol. 118: 1557–1565,
Steryl ferulates are plant sterols esterified to ferulic acid, a
common phenolic acid. This esterification leads to sterol esters
with improved biological properties, such as antioxidant activity.
Commercially available and extracted steryl ferulates from rice
bran are often limited in their sterol profiles. For further research
and later food applications, a simple enzymatic esterification could
address the lack of availability of single steryl ferulates. Whereas
several enzymatic procedures for the esterification of steryl fatty
acid esters have been published, no fully enzymatic procedure for
steryl ferulates has been reported so far. We optimized both direct
esterification of β-sitosterol with ferulic acid as well as transesterification with ethyl ferulate yielding steryl ferulates. The reaction
was catalyzed by a lipase from Candida rugosa, which lead to yields
of 35 and 55% for the direct esterification and transesterification,
respectively. Moreover, both reactions followed a similar time
course over incubation. The enzyme activity was rather low, which
is probably due to the specificity of the different isoenzymes of C.
rugosa lipase. However, successful conditions for a fully enzymatic
synthesis of steryl ferulates are reported for the first time.
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