Isoprenoid Fatty Acids in the Human Diet: Distinctive Geographical Features in Butterfats and Importance in Margarines Based on Marine Oils

Nondestructive detection of sunset yellow in cream based on near-infrared spectroscopy and interval random forest

Based on near-infrared spectrum and interval random forest, a fast quantitative analysis method for the content of sunset yellow content was established. The spectra of 132 cream pigment samples were obtained by FT-NIR spectrometer, and various preprocessing methods such as standard normal variable (SNV), wavelet transform (WT), and SG (Savitzky-Golay) were used to smooth and denoise the original spectrum. In this paper, WT and first-order differentiation were used as pretreatment and the Kennard-Stone algorithm was used to divide the data set. Finally interval partial least squares, partial least squares, interval random forest and random forest were used to construct an optimal quantitative analysis model. The experimental results show that the interval random forest can find the best sub-interval to achieve the prediction ability of the model. The R² (the coefficient of determination) and RMSEP (root mean square error of the prediction) of the prediction set are 0.8965 and 0.2454, respectively. The research results show that near-infrared spectroscopy combined with interval random forest algorithm is a fast and non-destructive method to detect the content of sunset yellow in cream.

Unusual fatty acids in the depot fat of the Canadian beaver (Castor canadensis)

Unusual fatty acids in the adipose tissue of the Canadian beaver were analysed by argentation thin-layer chromatography, gas-liquid chromatography and gas chromatography-mass spectrometry of several adducts and spectroscopic measurements. The total proportion of trans-octadecenoic fatty acids and the distribution of double bonds in these acids resembled those of ruminant fats. Because trans-11-18:1 was the main trans-18:1 isomer of beaver fat and a conjugated diene cis-9, trans-11-18:2 was also detected, it can be deduced that linoleic acid (cis-9, cis-12-18:2) is biohydrogenated in the beaver. The ideas that microbial processes intervene before normal absorption and fatty acid metabolism of the beaver is also supported by the larger amounts of anteiso odd-chain fatty acids with respect to the corresponding iso acids in the beaver depots. In addition, the distribution of double bonds in the cis-octadecenoic acids was wide, as it is in the depot fats of ruminants.

Presence of plasma branched-chain fatty acids in multineuronal degeneration, hepatosplenomegaly and adrenocortical insufficiency

We have previously reported a unique disorder in two brothers with multi-system neuronal degeneration, hepatosplenomegaly and adrenocortical deficiency. The clinical features were different from Refsum's disease. Biochemical analysis suggested that a metabolic defect of the omega 6 polyenoic fatty acid pathway may be involved. In the present study, were have further identified by gas chromatography-mass spectrometry two branched-chain fatty acids, phytanate and pristanate, in these two patients' plasma. This small, but unequivocally elevated elevated amount of branched-chain fatty acids were primarily localized in the triacylglycerols of plasma low density lipoprotein. Such branched-chain fatty acids were not detected in skin, liver and sural nerve samples. These two cases may represent an alternative metabolic error to that found in Refsum's disease leading to phytanate accumulation.