Sample preparation and determination of pesticides in fat-containing foods.

Pesticides are still a very important factor in food plant cultivation. The lipophilic character of most pesticides can lead to their accumulation in fat, which can have harmful effects on humans and animals. The aim of this review is to present current knowledge about the isolation and determination of pesticides in fatty commodities. The following techniques for isolation are discussed: solvent partitioning, solid phase and dispersive solid phase, QuEChERS-based procedures, matrix solid-phase dispersion, gel permeation chromatography, Soxhlet extraction, accelerated solvent extraction, and microextraction techniques. Chromatographic methods predominate in the analysis of pesticide residues in fatty matrices and, for this reason, the review focuses on these methods, particularly those combined with mass spectrometry. Analytical chemists still face the challenge - in the determination of pesticide residues in fatty matrices - of developing simpler and quicker procedures that consume less organic solvents.

Effects of casein non-phosphopeptide on the development of rat muscle analyzed using computed tomography scanning technology.

The effects of casein non-phosphopeptide (CNPP) on the muscle development of healthy rats and selected blood hormones levels were investigated. CT technology and the ELISA kit were employed to detect the cross-sectional area of each muscle group and blood hormone levels, respectively. The cross-sectional area of the trunk and lower limb muscles of resistance exercise group (REG) rats that were administered a high daily dose of CNPP for 50 days increased more significantly than that of the blank group rats, no exercise group (NEG) rats administered with the same daily dose of CNPP, and REG rats administered with the same daily dose of lactalbumin (P < 0.05).The more enhanced development of trunk and lower limb muscles in CNPP-administered REG rats was associated with a higher blood level of insulin, while no clear trends in blood levels of growth hormone and testosterone were observed. The present results have demonstrated that a combination of physical exercise and diet supplementation with CNPP can synergistically improve muscle mass.