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CN-122012653-A - Preparation method of starch-based alpha-glucan with non-debranching enzyme sensitivity

CN122012653ACN 122012653 ACN122012653 ACN 122012653ACN-122012653-A

Abstract

The invention discloses a preparation method of starch-based alpha-glucan with non-debranching enzyme sensitivity, and belongs to the technical field of food industry. The invention aims to realize efficient conversion of various different starch-based anti-digestion alpha-glucans without debranching enzyme sensitive structures so as to promote industrialization of products. The method comprises a starch liquefying process, a debranching process and a transglycosylation process, solves the problems of high viscosity and complex components of a high-concentration starch system, and is convenient for glycosyltransferase to efficiently modify starch so as to synthesize starch-based digestion-resistant alpha-glucan with different structures and properties.

Inventors

  • BAI YUXIANG
  • LI XIAOXIAO
  • FAN RUI

Assignees

  • 江南大学

Dates

Publication Date
20260512
Application Date
20260211

Claims (10)

  1. 1. A method for preparing starch-based α -glucan having a non-debranching enzyme-sensitive structure, the method comprising the steps of: (1) Adding 2U/g Dry starch ~4 U/g Dry starch beta-cyclodextrin glucosyltransferase into a starch suspension for liquefaction reaction, wherein the reaction conditions are that the temperature is raised to 100 ℃ within 50-70 min, and then the temperature is kept for 30-50 min, wherein the mass fraction (w/w) of starch in the starch suspension is 1-30%, and the temperature is reduced to 60 ℃ after the liquefaction reaction; (2) And (2) simultaneously adding pullulanase and 4, 6-alpha-glucosyltransferase into the reaction system obtained in the step (1) for enzymolysis, wherein the addition amount of the pullulanase is 15U/g Dry starch ~25 U/g Dry starch , the addition amount of the 4, 6-alpha-glucosyltransferase is 30U/g Dry starch ~35 U/g Dry starch , the enzymolysis condition is that the temperature is 40-45 ℃, the enzymolysis is carried out for 20-30 hours, the enzyme is inactivated after the enzymolysis, the reactant is subjected to centrifugation, the supernatant is collected, the supernatant is dialyzed, and the starch-based alpha-glucan is obtained after drying.
  2. 2. The method according to claim 1, wherein the mass fraction of starch in the starch suspension is 1%~2%、2%~3%、3%~4%、4%~5%、5%~6%、6%~7%、7%~8%、8%~9%、9%~10%、10%~11%、11%~12%、12%~13%、13%~14%、14%~15%、15%~16%、16%~17%、17%~18%、18%~19%、19%~20%、21%~22%、22%~23%、23%~24%、24%~25%、25%~26%、26%~27%、27%~28%、28%~29% or 29% -30%.
  3. 3. The method according to claim 1 or 2, wherein in step (1), the β -cyclodextrin glucosyltransferase is derived from Alkalophilic Bacillus sp.1011; Preferably, the beta-cyclodextrin glucosyltransferase is added in an amount of 2.1 U/g Dry starch 、2.2 U/g Dry starch 、2.3 U/g Dry starch 、2.4 U/g Dry starch 、2.5 U/g Dry starch 、2.6 U/g Dry starch 、2.7 U/g Dry starch 、2.8 U/g Dry starch 、2.9 U/g Dry starch 、3.0 U/g Dry starch 、3.1 U/g Dry starch 、3.2 U/g Dry starch 、3.3 U/g Dry starch 、3.4 U/g Dry starch 、3.5 U/g Dry starch 、3.6 U/g Dry starch 、3.7 U/g Dry starch 、3.8 U/g Dry starch 、3.9 U/g Dry starch or 4.0U/g Dry starch .
  4. 4. A method according to any one of claims 1 to 3, wherein the reaction conditions in step (1) are that after heating to 50 ℃, the solution is heated from 50 ℃ to 100 ℃ in 1 h, then the temperature is kept for 30 min, and after liquefaction, the temperature is reduced to 60 ℃.
  5. 5. The method according to any one of claims 1 to 4, wherein in the step (2), the pullulanase is derived from Bacillus thermoleovorans US a 10 and the 4,6- α -glucosyltransferase is derived from Lactobacillus reuteri a GtfB.
  6. 6. The method according to any one of claims 1 to 5, wherein in the step (2), the pullulanase is added in an amount of 15 U/g Dry starch 、16 U/g Dry starch 、17 U/g Dry starch 、18 U/g Dry starch 、19 U/g Dry starch 、20 U/g Dry starch 、21 U/g Dry starch 、22 U/g Dry starch 、23 U/g Dry starch 、24 U/g Dry starch or 25U/g Dry starch .
  7. 7. The method according to any one of claims 1 to 6, wherein the enzyme deactivation method comprises high temperature enzyme deactivation, acid-base enzyme deactivation, and ethanol enzyme deactivation; preferably, the dialysis cut-off molecular weight is above 1000 Da; Preferably, the drying method comprises freeze drying, atmospheric drying, spray drying, drum drying or microwave drying.
  8. 8. The method according to any one of claims 1 to 7, wherein in the step (2), the condition of the enzymolysis is that the reaction is carried out in a water bath at 40 ℃ for 24 h.
  9. 9. The method according to any one of claims 1 to 8, wherein in step (2), the amount of 4,6- α -glucosyltransferase added is 30U/g Dry starch 、31 U/g Dry starch 、32 U/g Dry starch 、33 U/g Dry starch 、34 U/g Dry starch 、35 U/g Dry starch .
  10. 10. The method according to any one of claims 1 to 9 or the use of starch-based α -glucan prepared by the method according to any one of claims 1 to 9 in the preparation of food, biologicals, pharmaceuticals.

Description

Preparation method of starch-based alpha-glucan with non-debranching enzyme sensitivity Technical Field The invention relates to a preparation method of starch-based alpha-glucan with non-debranching enzyme sensitivity, belonging to the technical field of food industry. Background Alpha-glucan is a homotype polysaccharide formed by connecting glucose units through alpha-glycosidic bonds, and is widely found in nature. The starch-based anti-digestion alpha-glucan is a type of alpha-glucan with anti-digestion characteristics, which is synthesized by taking starch as a substrate and utilizing 4, 3/6-alpha-glycosyltransferase through a specific process. Such polysaccharides have received wide attention in recent years in the fields of food science and nutrition because of their unique physiological functions and nutritional values. The digestion-resistant property of the compound can resist enzymolysis in the human digestive tract, so that the release and absorption of glucose are delayed, the prebiotic effect is exerted, the proliferation of beneficial intestinal flora is promoted, and various health benefits such as reducing blood sugar and improving lipid metabolism are possibly brought. The alpha-glucan shows rich physicochemical properties due to the structural diversity, has excellent dietary fiber and prebiotic potential, and is a functional polysaccharide with great development prospect. However, the current research on starch-based anti-digestion alpha-glucan is mainly focused on a laboratory stage, and is mostly carried out in a low-concentration starch system, and has a significant difference from a high-concentration condition in actual industrial production, so that the existing research result is difficult to directly apply to large-scale production. Therefore, there is an urgent need for a process for efficiently converting starch into a deep processed product with higher nutritional value and application efficacy, so as to realize high-valued and diversified applications of starch. In the conversion of starch, linear dextrins obtained by the introduction of debranching enzymes are easier to use as substrates for 4, 3/6-alpha-glycosyltransferases. The alpha-glucan contains (alpha 1-4) glycosidic bond and (alpha 1-6) glycosidic bond, and when the proportion of the (alpha 1-6) glycosidic bond is higher than 80%, the alpha-glucan has extremely strong digestion resistance (ensuring the effect of prebiotics), excellent solubility and solution stability, and is very suitable for the fields requiring clear, low-viscosity and high-benefit prebiotic formulation. Considering whether the constituent bonds of the starch-based anti-digestion alpha-glucan prepared in the reaction are degraded by debranching enzymes, and the influence of the linear dextrins produced by liquefaction and debranching on the composition and yield of the 4, 3/6-alpha-glycosyltransferase product, different process routes and reaction conditions need to be designed for the product with a specific structure to obtain the target anti-digestion alpha-glucan with high yield. The invention lays a good foundation for realizing the large-scale industrialized production of the starch-based anti-digestion alpha-glucan. Disclosure of Invention In order to overcome the defects, the invention provides a high substrate concentration conversion method of starch-based anti-digestion alpha-glucan. Aims at realizing the efficient conversion of various different starch-based anti-digestion alpha-glucans without debranching enzyme sensitive structures so as to promote the industrialization of products. The method comprises a starch liquefying process, a debranching process and a transglycosylation process, solves the problems of high viscosity and complex components of a high-concentration starch system, and is convenient for glycosyltransferase to efficiently modify starch so as to synthesize starch-based digestion-resistant alpha-glucan with different structures and properties. The invention provides a method for preparing non-debranching enzyme sensitive starch-based anti-digestion alpha-glucan by using a high concentration substrate, which comprises the steps of liquefying starch by using liquefying enzyme, inactivating enzyme after liquefying, simultaneously debranching and transglycosylating reactions of the starch by using debranching enzyme and glycosyltransferase based on the insensitivity of a target product to the debranching enzyme, inactivating enzyme after the reaction is finished, centrifuging, and drying supernatant by alcohol precipitation dialysis to obtain the target product starch-based anti-digestion alpha-glucan. The invention also provides a method for preparing starch-based anti-digestion alpha-glucan, comprising the steps of: (1) And adding liquefying enzyme into the starch suspension to carry out liquefaction reaction, wherein the mass fraction (w/w) of starch in the starch suspension is 1-30%. (2) And (3) adding debranching en