Tuning of the enzyme ratio in a neutral redox convergent cascade: A key approach for an efficient one-pot/two-step biocatalytic whole-cell system.

The efficiency of a versatile in vivo cascade involving a promiscuous alcohol dehydrogenase, obtained from a biodiversity search, and a Baeyer-Villiger monooxygenase was enhanced by the independent control of the production level of each enzyme to produce ε-caprolactone and 3,4-dihydrocoumarin. This goal was achieved by adjusting the copy number per cell of Escherichia coli plasmids. We started from the observation that this number generally correlates with the amount of produced enzyme and demonstrated that an in vivo multi-enzymatic system can be improved by the judicious choice of plasmid, the lower activity of the enzyme that drives the limiting step being counter-balanced by a higher concentration.

Hepatic metabolic effects of Curcuma longa extract supplement in high-fructose and saturated fat fed rats.

The metabolic effects of an oral supplementation with a Curcuma longa extract, at a dose nutritionally relevant with common human use, on hepatic metabolism in rats fed a high fructose and saturated fatty acid (HFS) diet was evaluated. High-resolution magic-angle spinning NMR and GC/MS in combination with multivariate analysis have been employed to characterize the NMR metabolite profiles and fatty acid composition of liver tissue respectively. The results showed a clear discrimination between HFS groups and controls involving metabolites such as glucose, glycogen, amino acids, acetate, choline, lysophosphatidylcholine, phosphatidylethanolamine, and β-hydroxybutyrate as well as an increase of MUFAs and a decrease of n-6 and n-3 PUFAs.

Metabolomic and Lipidomic Analysis of Serum Samples following Curcuma longa Extract Supplementation in High-Fructose and Saturated Fat Fed Rats.

We explored, using nuclear magnetic resonance (NMR) metabolomics and fatty acids profiling, the effects of a common nutritional complement, Curcuma longa, at a nutritionally relevant dose with human use, administered in conjunction with an unbalanced diet. Indeed, traditional food supplements have been long used to counter metabolic impairments induced by unbalanced diets. Here, rats were fed either a standard diet, a high level of fructose and saturated fatty acid (HFS) diet, a diet common to western countries and that certainly contributes to the epidemic of insulin resistance (IR) syndrome, or a HFS diet with a Curcuma longa extract (1% of curcuminoids in the extract) for ten weeks.

Prevalence and specificity of Baeyer-Villiger monooxygenases in fungi.

Out of 107 fungal strains belonging to three phyla (Ascomycota, Basidiomycota and Zygomycota) and 46 genera, 86 exhibited Baeyer-Villiger monooxygenase (BVMO) activity against racemic bicyclo[3.2.0]heptenone.

Long-term high fructose and saturated fat diet affects plasma fatty acid profile in rats.

As the consumption of fructose and saturated fatty acids (FAs) has greatly increased in western diets and is linked with an increased risk of metabolic syndrome, the aim of this study was to investigate the effects of a moderate (10 weeks) and a prolonged (30 weeks) high fructose and saturated fatty acid (HFS) diet on plasma FA composition in rats. The effects of a few weeks of HFS diet had already been described, but in this paper we tried to establish whether these effects persist or if they are modified after 10 or 30 weeks. We hypothesized that the plasma FA profile would be altered between 10 and 30 weeks of the HFS diet.

Proteomic of lipid rafts in the exocrine pancreas from diet-induced obese rats.

In the present work, we induced obesity in rats with high-energy-starch diet and studied exocrine pancreas response. The zymogen granule (ZG) or purified plasma membrane (PM) from the exocrine pancreas was used for the isolation of the detergent-resistant membranes (DRMs). Based on high content of cholesterol, GM1, the bile salt dependent lipase (BSDL), and GP2 enrichment, the low-density fractions were defined as lipid rafts.

Proteomic characterization of lipid rafts markers from the rat intestinal brush border.

To assess intestinal lipid rafts functions through the characterization of their protein markers, we have isolated lipid rafts of rat mucosa either from the total membrane or purified brush-border membrane (BBM) by sucrose gradient fractionation after detergent treatment. In both membrane preparations, the floating fractions (4-5) were enriched in cholesterol, ganglioside GM1, and N aminopeptidase (NAP) known as intestinal lipid rafts markers. Based on MALDI-TOF/MS identification and simultaneous detection by immunoblotting, 12 proteins from BBM cleared from contaminants were selected as rafts markers.

Optimal design for the maximization of Penicillium cyclopium lipase production.

Penicillium cyclopium triacylglycerol lipase production was maximized in stationary batch culture. We used a surface response methodology based on a Doehlert experimental design to study the effect on the lipase activity released in the culture medium of the three most important factors: substrate concentration, pH and inoculum. Besides reducing the number of experiments required for optimization, this technique allowed us to quantify the lipase activity in any part of the experimental domain.