Lysine-glucose

Por fhe specimens of bafch III, bofh fhe collagenase and borohydride freafmenfs were omiffed fo enable analysis of furosine, which is formed by acid hydrolysis of fhe non-reduced glucose-lysine condensation producf. 

Effect of a Glucose-Lysine Reaction Mixture on Protein and Carbohydrate Digestion and Absorption... 

The present study was performed in order to examine whether the compounds in a glucose-lysine reaction mixture per se may influence the digestion and uptake of proteins. Since such an effect was noted, the study was extended to include the digestion and uptake of carbohydrates as well. 

A control diet was prepared as follows Tha labelled egg-white protein was mixed with a basal diet in the proportion 2 98. The basal diet contained 10% casein, 10% sucrose, about 70% starch and 5% maizeoil, as well as vitamins and minerals. A small amount of [sHl-lysine was added to this mixture, giving a ratio of tritium to (11 C) dpm of approximately 10 1. The experimental diet was obtained by adding a small amount ot the glucose-lysine reaction mixture to the control diet. 

Since the glucose-lysine reaction mixture used in this study consisted of a number of different substances, it was of interest to study whether the observed inhibitory effect in vitro could be attributed to some specific compound(s). In order to obtain a separation, an aliquot of the LMW fraction, radiolabel led by [U- glucose added to the reactants, was applied on a Sephadex G-50 column and eluted with water. The UV absorbance was recorded and the eluate was collected in fractions. The degree of inhibition effected by small samples of equal volume from each fraction and exerted on carboxypeptidase A and purified aminopeptidase N was determined as well as the radioactivity... 

Figure 2. Total sugar absorbed from rat intestine at different times after the ingestion of 760 mg sucrose in solution with (U), and without (AJ 8 mg of the high molecular weight (HMW) fraction of the glucose-lysine reaction mixture (IS).

It is clear that the LMW fraction from the glucose-lysine reaction mixture affected, down to a concentration of at least 0.25 mg/ml, the rates of hydrolysis catalyzed by some, but not all, of the enzymes involved in protein digestion in vitro. Car-boxypeptidase A and aminopeptidase N were inhibited by a number of substances in the mixture, some being more effective than others. Efforts to characterize these compounds are in progress. 

Table 3.2 Some of the volatiles isolated from a glucose-lysine system, pH 10.1, heated at 60 °C at atmospheric pressure and 600 MPa105...

Eichner486 reported the results of an interesting experiment. By interacting a sodium linoleate solution, already containing 10 mol% hydroperoxide, with a preheated glucose-lysine system, he showed that the proportion of hexanal formed was reduced from 0.35 to 0.09 mol mol 1 peroxide decomposed. Concomitantly,... 

V. M. Hill, D. A. Ledward, and J. M. Ames, Influence of high hydrostatic pressure and pH on the rate of Maillard browning in a glucose-lysine system, J. Agric. Food Chem., 1996, 44, 594-598. 

L. Bates, J. M. Ames, D. B. MacDougall, and P. C. Taylor, Laboratory reaction cell to model Maillard color development in a starch-glucose-lysine system, J. Food Sci., 1998,... 

Jing, H. and Kitts, D.D. 2000. Comparison of the antioxidative and cytotoxic properties of glucose-lysine and fructose-lysine Maillard reaction. Food Res. Int. 33, 509-516. 

Kitts, D.D., Wu, C.H., Stich, H.F., and Powrie, W.D. 1993. Effect of glucose-lysine Maillard reaction product on bacterial and mammalian cell mutagenesis. J. Agric. Food Chem. 41, 2353-2358. 

The Maillard reaction between reducing carbohydrates and amines is among the most important flavor generating reactions in thermally processed foods (5). Thus, it might be expected that in foods treated with HHP, but at low temperatures, some of the typical aroma compounds might not be formed. Only two studies about the influence of HHP on the formation of volatiles in Maillard model systems are currently available (6, 7). Bristow and Isaacs (d) reported that at 100°C, the formation of volatiles from xylose/lysine was generally suppressed when HHP was applied. Hill et al. (7) confirmed this observation for a glucose/lysine system. However, it has to be pointed out that the samples analyzed were not reacted in a buffered system and, also, the reaction time of the pressure-treated and untreated sample were not identical. 

Cooking starch in the presence of amino acids may favour the occurrence of Maillard reactions, lowering the bioavailability of lysine in the diet. 13C CPMAS was used to follow the effect of Maillard reactions on the bioavailability of potato starch.124 A loss of crystallinity was found for the three samples studied starch, amylopectin, and amylose, being more marked for amylose. A similar study on chestnut starch indicated that Maillard reactions do not influence significantly its digestibility.125 NMR was used to characterize some Maillard reaction products extracted from model reactive mixtures such as starch-glucose-lysine 126 and lactose-lysine.127... 

Kwak, E.J. and Lim, S.l. Inhibition of browning by antibrowning agents and phenolic acids or cinnamic acid in the glucose-lysine model, J. Sci. Food Agric., 85, 1337, 2005. 

The glucose-lysine Amadori compounds monofructosy1-lysine and dlfructosy1-lysine have been Isolated, and the kinetics of their formation studied. 1-Deoxy-l-tolylamino-D-fructopyranose has been obtained by amlnatlon of fructose with g -toluldine, and shown to form an acyclic oxime and, on reaction with glycine ethyl ester, the glycosylamlne derivative (3). ... 

Glucose-lysine- 100°C- Radical (ABAP) Crocin bleaching ... 

Cuzzoni, M.T. Stoppini, G. Gazzani, G. Influence of water activity and reaction temperature of ribose-lysine and glucose-lysine Maillard systems on mutagenicity, absorbancy, and content of furfurals. Food Chem. Toxicol. 1988, 26,815-822. 

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