IL37677A - Enzymatic production of glucose from polysaccharides - Google Patents

Description

Specification of the invention having the PROCESS FOR GLUCOSE BY AN ENZYMATIC SCISSION OP POLYSACCHARI SNAM Dino Franco Carlo The present invention refers to a process for producing glucose by an matic scission of More particularl the present invention relates to the enzymatic scission of glucose and above all to products obtained by a partial sion of Processes for obtaining glucose starting from starchs are they sting of melting the starch suspension at high temperatures by means of amylase or acidsj treating the obtained solution by amyloglucosidase which hydrolyzes oligo saccharides to However these processes have some drawbacks owing to the difficult handling of amyloglucosidase and to the fact it cannot be again utilized because of its dispersion into the reaction medium from which it cannot be This fact causes one other it limiting the conversion to cer tain more than which amyloglucosidase does not more its catalytic activity and is generally last in the following treatments of removing the product from the reaction It has now been found a process allowing crystalline glucose or syrups ha oligomers of ving a high glucose content to be obtained by an enzymatic scission me without the aforementioned Particularly the that is the object of the present con eists in contacting starch suspension melted by or with filamentous structures englobing suoh a way the enzym its dispersion into the reaction mass and the possible pollution of the reaction product are The employable filamentous structures and the enzym englobing method are the ones described in the patent according to which the fibers englobing the enzyme may be prepared from polymer 30lu tions able to give fibers wherein are dispersed enzymatic compounds of very little drops of the magnitude order of the The so obtained emulsion may be spun wet or dry to give rise to a fiber inside very little cavities in which are placed the mes which are from the enviroment by a very thin Said membrane prevents the breakage of the enzyme and its dispersion in to the reaction anyhow it allows the enzyme can exert its catalytic The polymers which may be used usefully at this purpose must exist in solu tion at a temperature consistent with the stability of enzyme in a sol vent which must be substantially immiscible with the solvent wherein the enzyme is dissolved or Their solvent must not be harmful for the stability of the enzyme and they must not present a desactivating action as to the in case of wet the coagulation agent must be miscible with the solvent of the polymer and have the aforementioned Among the polymers which may englobe the it is possible to the etherified cellulosic the the polymers and copolymers obtained from vinyl vinyl vinylidene styrene and fur the the butyral polyvinyl and the In order to perform the process of the present invention a very advantageous use is made of esterified cellulosic Besides keeping all the advantages of using enzymes for the production of the inventive process presents remarkable For example the exceptional length of the englobed we more than one year tested without an activity has a sure influence on the Δ further owed to the englobed consists of the fact that there is no problem of removing the enzyme from the produc that makes easy the process of extracting crystalline One other great given by the possibility of continuous that semplifies the plant and allows the process to be The inventive process may be carried out as a batch wherein the sub s contact occurs for the time necessary to obtain the wished e quivalent sugar content of the hydrolized compound calculated as dextrose and expressed as per cent on the weight of the present dry The hydrolized substrate may then be removed and substituted by a fresh sub so using the same enzymatic for an unlimited number of working According to a preferable method of performing the inventive the en zymatie fiber may be utilized in a continuous it may be placed in one or more columns wherein is flowing the By suitably regulating the flow the fiber amount and its enzymatic con it is possible to obtain conversion at the wished effluent Some other working will be pointed out by the following exam hereinafter reported in order to better illustrate the present Example 1 In a 27 g of cellulose triacetate under dis solved into 273 g of methylene chloride the solution was then cooled at The enzyme solution was separately 3 g of Diazyme dust were dissolved in a mixture 45 The solution was filtered to remove the enzyme insoluble sized to a volume and cooled at 45 of the aforesaid solution collected and added to the polymer so emulsion was performed under a strong stirring at for ho so obtained emulsion poured into a little the extrusion the spinneret happening under a nitrogen pressure of The filament coagulated in toluene at a temperature of and was recovered on a It was dried under acuum to remove A little skein of 5 g of the obtained filament was put into a glass column 1 cm X having a thermostable jacketβ The column is fed by a peristaltic pump at a 10 A closed process working system was The substrate thermostated at was fed to the bottom it too being thermostated at The partially hydrolized solution came out from the top and was recycled to the starting every use was made of a substrate consisting ml of a starch solution at pretreatedi by till to a value of The proportion of sugar ingredients carried out by the somoggi use was of the glucose enzymatic det The tests were carried out for a continuous period of three At the end of any cycle the conversion having reached the maximum va the substrate was Before beginning a new the column was fed by deioni ed water for about in order to the fiber and to remove the possible traces cf substrate and 30 cycles were carried out at The conversion yields ranged from 102 to theoretical maximum yield is because of the embodying of water during the The final product quality was checked by chromatography kg of glucose were Example 2 By using a column equal to the one of example 1 the same amount of and by working in same sperimental cycles of 24 hours were 00 ml of starch solution at by sed the from to 55 Example 3 According to example some cycles of hours were Uee was made of a substrate consisting of ml of a starch solution at 18 liquefied by an acid hydrolysis till to a value of After hours the maximum conversion was obtained 88 Example 4 Aocording to the art of example 1 a filament consisting of was Use was made of the 30 product of Y0WA 0 it being a polymer solution in symmetrical The results obtained by employing the same column of the preceding examples were the same Example 5 Diazyme product was dissolved in deionized water and the obtained mixture was filtered to remove the insoluble Enzyme was then precipitated by acetone at The precipitate was again dissolved in the minimum amount of in such way the activity was encreased with regard to the starting one 1 This compound was englobed into a cellulose triacetate A filament was obtained having an activity equal to mg of Diazyme dust on gram of fi By working according to examples 3 after hours making use of 5 g of the aforesaid 5 liter of a starch was brought to the maximum conversion 102 Example 6 Diazyme product was dissolved in water and it was dialyzed by deionized water for 24 The enzymatic solution was then purified on a c cellulose The recovered at contained A precipitate was obtained by and it was again dissolved by water in order to obtain an enzyme derivation more active than the one of examples 1 and 2 100 g of a cellulose triacetate having an activity equal to 5 of azyme dust on gram of were put on a glass column 12 10 made a substrate consisting a starch solutio at pre treated by A the a solution was By flow to the reached the conversion insufficientOCRQuality

Claims (1)

1. glucose by a among A preceding c in tha constituted by cellulose 1 by insufficientOCRQuality