Maple analysis

E. Podehrad, M. Heil, S. Leih, B. Geier, T. Beck, A. Mosandl, A. C. Sewell and H. Bohles, Analytical approach in diagnosis of inherited metabolic diseases maple syrup urine disease (MSUD)-simultaneous analysis of metabolites in urine by enantioselective multidimensional capillary gas chromatography-mass specti ometiy (enantio-MDGC-MS) , 7. High Resolut. Chromatogr. 20 355-362(1997). 

As the name implies, the odor of urine in maple syrup urine disease (brancbed-chain ketonuria) suggests maple symp or burnt sugar. The biochemical defect involves the a-keto acid decarboxylase complex (reaction 2, Figure 30-19). Plasma and urinary levels of leucine, isoleucine, valine, a-keto acids, and a-hydroxy acids (reduced a-keto acids) are elevated. The mechanism of toxicity is unknown. Early diagnosis, especially prior to 1 week of age, employs enzymatic analysis. Prompt replacement of dietary protein by an amino acid mixture that lacks leucine, isoleucine, and valine averts brain damage and early mortality. 

Valentin-Blasini L, Mauldin JP, Maple D, Blount BC (2005) Analysis of perchlorate in human urine using ion chromatography and electrospray tandem mass spectrometry. Anal Chem 77 2475-2481... 

Table VII Sampling and analysis precision for co-located rain samplers of Che Maple Leaf site (units = ppm unless Indicated)...

Doner, L. W. and Hicks, K. B. 1982. Lactose and the sugars of honey and maple Reactions, properties and analysis. In Food Carbohydrates D.R. Lineback and G.E. In-glett (Editors). AVI Publishing Co., Westport, Conn. pp. 74-112. 

A fourth compound obtained from maple as a pure crystalline compound had a molecular weight, carbon, hydrogen, and methoxyl analysis characteristic of a diphenylmethane with four methoxyl and two hydroxyl groups. The NMR spectrum of the acetate also had a peak at 6.10r equivalent to two protons and presumably caused by the methylene bridge,... 

I Matsuda, J Asaka, I Akaboshi, F Endo, H Mitsubuchi, Y Nobukuni. Maple syrup urine disease complete primary structure of the El-(3 subunit of human branched chain a-ketoacid dehydrogenase complex deduced from the nucleotide sequence and a gene analysis of patients with this disease. J Clin Invest 86 242-247, 1990. 

Stuckel, J. G. and Low, N. H. (1995). Maple syrup authenticity analysis by anion-exchange liquid chromatography with pulsed amperometric detection. J. Agric. Food Chem. 43, 3046-3051. 

As an example of a symbolic calculation. Fig. 5 displays a Mathcad solution of one 4X4 block of the secular determinant of a Hiickel molecular orbital calculation done in Exp. 41 for orf/ro-benzosemiquinone (compare with Table 41-2). Mathcad is a software package for numerical analysis but also makes use of a subset of the symbohc routines of Maple. The algebraic expansion of the determinant is generated and solved with two... 

The procedure has been applied to the analysis of control urine and that from a patient with maple-syrup-urine disease. The results from 5 separate analyses in each case gave standard deviations of less than 10% of the mean. This was routinely achieved where the level of an amino acid was about 1 ng. 

Like other pyrolysis oil processes. Biocarbons Corporation s reactor produces a large number of oil compounds. For mixed hardwood (maple, birch and beech) pyrolyzed at typical operating conditions, 69 peaks were found by GC/MS analysis. Of these, the 14 peaks present at above 2 mole percent, represented 45 mole percent of the product that came through the GC. The 27 peaks between 1 and 2 mole percent, represented an additional 37 mole percent of the product. These compounds that were identified are listed in Table 1, in order of appearance (time). Several of the 4-position groups could also be occurring at the 3 position. All are reactable to make a phenol-forma Idehvde type adhesive. Pyrolysis oil from pine that was nude at the same operating condition (but has not yet been tested for adhesive use) had essentially the same compounds present at >1 mole percent, but at different relative concentrations. Some lower concentration compounds such as fatty acids are only produced from pine, but these compounds are specific to softwoods and the composition of softwoods. A comparison between the mixed hardwoods and pine products is shown in Table 2. 

This book presents Maple solutions to a wide range of problems relevant to chemical engineers and others. Many of these solutions use Maple s symbolic capability to help bridge the gap between analytical and numerical solutions. The readers are strongly encouraged to refer to the references included in the book for a better understanding of the physics involved, and for the mathematical analysis. 

Phenolic and furfural compounds in apple juice were determined by HPLC using a combination of ELD and DA-UVD. LOD for ELD were 4 to 500 times greater than those for spectrophotometric detection. The content of phenolics varied from 30 to 115 mgL, including major phenolic components such as chlorogenic acid (95), p-coumaroylquinic acid (98) and phloridzin (96) and minor ones such as caffeic acid (25), p-coumaric acid (26), ferulic acid (69), gallic acid (8), protocatechuic acid (27) and catechin (3) . The same methods were also applied for the analysis of maple products. The phenolic content was dependent on the source of the product. Application of reverse osmosis to maple sap caused a relative decrease of aldehydes and alcohols and an increase of phenolic acids. 

Helrich K. 1990. 964.1 Formaldehyde in maple sirup Spectrophotometric method. In Helrich K, ed. Official methods of analysis of the Association of Official Analytical Chemists. Arlington, VA Association of Official Analytical Chemists, Inc., 1037-1038. 

The coupling of SNIF-NMR with stable isotope ratio analysis/mass spectrometry has been the basis of a method for detection of adulteration of maple syrup with beet, cane, or com sugar.192 Adulteration of mustard oil by the addition of synthetic allyl isothiocyanate, its major component, is of economic interest, and therefore a combined NMR and mass spectrometry method was developed, enabling the distinction between the natural and the synthetic compound, as well as the determination of the geographical origin of natural mustard oils.193 Similar methods have been used for the analysis of flavourings such as vanilla flavour (vanillin and p-hydroxybenzaldehyde),194195 benzaldehyde,196 and others.197... 

---