Sucrose enzymatic hydrolysis

Liquid sucrose and Hquid invert, generally made by redissolving white sugar and inverting with invertase enzyme, are refinery products in Europe and outside the United States. In the United States they have been almost completely replaced by cheaper com symps made by enzymatic hydrolysis of starch and isomerization of glucose. 

Corn steep liquor contains 2.5% invert sugars and 50% water. The rest of the feed is considered as residual solids. Beet molasses containing 50% sucrose, 1% invert sugar, 18% water and remainder solids are mixed with corn steep liquor in a mixing tank. Water is added to produce a diluted mixture with 2% invert sugar, 125 kg com steep hquor and 45 kg molasses, which is fed into an enzymatic hydrolysis tank. 

Fructose has a much sweeter taste than glucose, hence the transformation of glucose derived from enzymatic hydrolysis of starch from com, provides an alternative sweetener to sucrose (a disaccharide of glucose and fructose). This replaced the use of sugar cane by the US soft drinks and candy industry (and effectively destroyed the economy of Cuba in the process). 

Bioethanol can be produced from a large variety of carbohydrates with a general formula of (CHjO) . Chemical reaction is composed of enzymatic hydrolysis of sucrose followed by fermentation of simple sugars. Fermentation of sucrose is performed using commercial yeast such as Saccharomyces cerevisiae. First, invertase enzyme in the yeast catalyzes the hydrolysis of sucrose to convert it into glucose and fmctose. 

Sucrose and lactose occur widely as the free sugars, lactose in the milk of mammals, and sucrose in fruit and plants (especially in sugar cane and sugar beet). Maltose is the product of enzymatic hydrolysis of starch, and cellobiose is a product of hydrolysis of cellulose. 

K. Y. Chang, S. H. Wu, and K. T. Wang, Preparation of hepta-O-acetyl sucroses and hexa-O-acetyl sucroses by enzymatic hydrolysis, J. Carbohydr. Chem., 10 (1991) 251-261. 

Invertase (EC 3.2.1.26) catalyzes the hydrolysis of P-fructofuranosides and has been used in analytical chemistry (biosensors), in confectionary, and in the production of inverted syrup (1). Invert sugar syrup, which can be obtained by acid or enzymatic hydrolysis of sucrose, is a valuable commercial product especially in countries where the main sources of sugar are beet or cane. With acid hydrolysis, the final syrup is often contaminated with colored oxidation compounds, which arise from cyclization of hex-oses at low pH and high temperatures (2-4). Such a problem does not occur... 

As a result of widespread concern about weight control, the production of lipid materials with reduced or zero calories has been of special interest recently. The lipid-based fat replacers are esters that resist enzymatic hydrolysis, are poorly absorbed, have relatively low-energy content, or have different modes of metabolism. Many of these materials can be made from soybean oil or contain soybean oil fatty acids. Sucrose polyester or other synthetic esters and diacylglycerol oils are examples of these low-calorie fat substimtes (268-274). 

D) Enzymatic Hydrolysis. Place in a test tube 2 ml of starch suspension, and in another tube 2 ml of sucrose solution. Add about the same volume of saliva to each (obtained by chewing a small piece of paraffin to promote secretion). Place the tubes in a water bath at 37-40 and allow to stand for 15 minutes. Test with Fehling s solution. 

The easiest obtainable carbohydrates from sucrose are o-glucose and o-fructose (Fig. 10). Thereby acidic or enzymatic hydrolysis leads to these two building blocks... 

Mandenius CF, Billow L, Danielsson B et al. (1985) Monitoring and control of enzymic sucrose hydrolysis using on-line biosensors. Appl Microbiol Biotechnol 21(3 ) 135-142 Marsden WL, Gray PP (1986) Enzymatic hydrolysis of ceUulase in lignocellulosic materials. CRC Critic Rev Biotechnol 3 235-274... 

Michaelis and Menten made a fortunate choice to study the enzymatic hydrolysis of sucrose ... 

Initiation/Termination Control of Enzyme Reaction. The enzymatic hydrolysis of sucrose was studied at 25 C through a monitoring of the formation rate of reducing sugar products (an equimolar mixture of glucose and fructose) in an aqueous suspension of the enzyme-loaded capsules. The suspension (50 mL) initially contained 100 mM of the substrate and 13.5% (v/v) of the capsules with a total of 200 mg of the encapsulated enzyme. On/off control was tested by investigating the batch reaction kinetics at pH 5.5 (at which the reaction occurs) and at pH 4.5 (at which the reaction stops). The adjustment of pH was made by quick additions of a small amount of 2M HCl or NaOH. 

Invert sugar a mixture of equal parts o-glucose and D-fructose which, in contrast to dextrorotatory sucrose, is levorotatoiy (see Mutarotation). I.s. is generated by acid or enzymatic hydrolysis of sucrose. Because bees have the corresponding invertase, honey is 70-80% I.s. The sweet taste is essentially due to the fructose. 

Sucrose is extracted from sugar cane and sugar beets and is purified and sold in very large amounts for use in foods. Maltose (malt sugar) is made by the enzymatic hydrolysis of starch, which is a polyglucose. Lactose is the sugar in milk. It is not as sweet as sucrose. 

An important application area of ion chromatography in the characterization of fruit juices is the analysis of carbohydrates. Traditionally, sorbitol and the main sugars such as glucose, fructose, and sucrose were determined with enzymatic methods, which are usually very sensitive and specific. Interferences caused by the matrix are rare however, they are possible when determining sucrose. The principle of the sucrose determination is based on the determination of the glucose content prior to and after enzymatic hydrolysis of sucrose. Because fixiit juices often contain large amounts of glucose in the presence of small amounts of sucrose, precise quantification of small sucrose concentrations... 

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