Biochemical composition

Variety of biochemical composition and physical features of milk, as well as compound forms of mineral components foreordain necessity to develop the analytical procedures, in which initial sample state suffers minimum change. Absence of dried milk reference standai ds (RSMs) is an obstacle to use nondestructive XRF for solving the given analytical task. In this communication results of nondestmctive x-ray fluorescence determination of Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Zr in dried milk powders of limited mass (less than 2 g), obtained with using plant RSMs to calibrate, ai e discussed. 

This equation was originally proposed for "average" plankton, a category that included both zooplankton and phytoplankton. This mean elemental ratio of C/N/P = 106/16/1 by atoms is highly conserved (Falkowski et al., 1998) and reflects the average biochemical composition of marine phytoplankton and their early degradation products. 

Table I Summary of the regional differences in the biochemical composition of the intervertebral disc...

Miliou, H., N. Zaboukas, and M. Moraitou-Apostolopoulou. 1998. Biochemical composition, growth, and survival of the guppy, Poecilia reticulata, during chronic sublethal exposure to cadmium. Arch, Environ. Contam. Toxicol. 35 58-63. 

This example belongs to chemotaxonomy, a discipline that tries to classify and identify organisms (usually plants, but also bacteria, and even insects) by the chemical or biochemical composition (e.g., fingerprint of concentrations of terpenes, phenolic compounds, fatty acids, peptides, or pyrolysis products) (Harbome and Turner 1984 Reynolds 2007 Waterman 2007). Data evaluation in this field is often performed by multivariate techniques. 

Due to the lack of bioassays that mimic the situation of toxin-containing food particles, most of the work has been performed on herbivores that feed on diets of phytoplankton species with different degrees of toxicity. This has led to multiple variant parameters, not allowing the direct comparison of effects due to the varying toxin contents. In a few cases, these studies have the advantage of being able to directly compare different clones of one species with variable toxicities but otherwise comparable biochemical composition. There, the effect of the toxins can be determined without overlaying effects due to different nutritional quality of the food. 

Mehta, A., Singh, S. P. (2004). Biochemical composition and chipping quality of potato tubers during storage as influenced by fertilizer application. J. Food Sci. TechnoL, 41, 542-547. 

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