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The effect of particle size on the extraction of tannins by microwave assisted extraction (MAE) was studied for the first time to our knowledge. Maritime pine ( Pinus pinaster ) bark from the South West of France was sieved into five ranges of particle size before extraction was carried out in an ethanol–water solution. For each extraction, the extraction yield, the total polyphenolic content, the condensed tannins content, and the sugar content were quantified. The extracts were characterized by their reactivity to formaldehyde, Fourier transformed infrared spectroscopy (FTIR), 1 H NMR, and heteronuclear single correlation spectroscopy 2D NMR (HSQC 2D NMR). The MAE was also compared to a hot water based extraction. The effect of the particle size on the extraction efficiency was studied. The HSQC 2D NMR revealed that (epi) catechin, epicatechin gallate, epigallocatechine, and epigallocatechine gallate were obtained. Higher amounts of condensed tannins, sugars, and simple flavonoids were extracted by MAE extraction. [ABSTRACT FROM AUTHOR]

In this paper, it is shown how vaporous cavitation in lubricant films can be modeled in a physically justified manner through the constitutive (compressibility) relation of the fluid. The method treats the flow as a homogeneous mixture employing a "void fraction" variable to quantify the intensity of cavitation. It has been already proposed to study cavitation in fluid mechanics. It is shown how the widely used Jakobsson-Floberg-Olsson (JFO) / Elrod-Adams (EA) mass flow conservation model can be compared with this new model. Moreover, the new model can incorporate the variation of the viscosity in the cavitation region and allows the pressure to fall below a cavitation pressure. Numerical computations show that discrepancy with JFOIEA is mostly associated with light loading condition, starved situation or viscosity effects. [ABSTRACT FROM AUTHOR]

Highlights: [•] Tannins from maritime pine bark were extracted with three extraction methods. [•] Extracts are characterised with spectrometric methods, FTIR and RP-HPLC. [•] The highest amounts of tannins were obtained with low concentrations of NaOH. [•] Results are different for extracts obtained from different trees with the same extraction method. [ABSTRACT FROM AUTHOR]

Abstract Background Sporadic colorectal cancers (CRC) are multifactorial diseases resulting from the combined effects of numerous genetic, environmental and behavioral risk factors. Genetic association studies have suggested low-penetrance alleles of extremely varied genes to be involved in susceptibility to CRC in Caucasian populations. Methods Through a large genetic association study based on 1023 patients with sporadic CRC and 1121 controls, we tested a panel of these low-penetrance alleles to find out whether they could determine "genotypic profiles" at risk for CRC among individuals of the French population. We examined 52 polymorphisms of 35 genes – drawn from inflammation, xenobiotic detoxification, one-carbon, insulin signaling, and DNA repair pathways – for their possible contribution to colorectal carcinogenesis. The risk of cancer associated with these polymorphisms was assessed by calculation of odds ratios (OR) using multivariate analyses and logistic regression. Results Whereas all these polymorphisms had previously been found to be associated with CRC risk, especially in Caucasian populations, we were able to replicate the association for only five of them. Three SNPs were shown to increase CRC risk: PTGS1 c.639C>A (p.Gly213Gly), IL8 c.-352T>A, and MTHFR c.1286A>C (p.Ala429Glu). On the contrary, two other SNPs, PLA2G2A c.435+230C>T and PPARG c.1431C>T (p.His477His), were associated with a decrease in CRC risk. Further analyses highlighted genotypic combinations having a greater predisposing effect on CRC (OR 1.97, 95%CI 1.31–2.97, p = 0.0009) than the allelic variants that were examined separately. Conclusion The identification of CRC-predisposing combinations, composed of alleles PTGS1 c.639A, PLA2G2A c.435+230C, PPARG c.1431C, IL8 c.-352A, and MTHFR c.1286C, highlights the importance of inflammatory processes in susceptibility to sporadic CRC, as well as a possible crosstalk between inflammation and one-carbon pathways.