Arabinoxylan prepared from corn bran and having a health-promoting activity

Abstract

The present application provides a kind of arabinoxylan with beneficial activity prepared with corn skin as raw material.The arabinoxylan is composed of xylose, arabinose, glucose, galactose, rhamnose, mannose, glucuronic acid, galacturonic acid, fucose, ribose according to the molar ratio of 104.6:82.6:21.0:16.8:8.9:5.1:4.3:1.6:1.3:1, and the molecular weight is 2.51-10 kDa.The present application uses xylanase Scxyn22 to prepare arabinoxylan with specific molecular weight distribution and monosaccharide composition, the molar ratio of arabinose / xylose reaches 0.79, has unique apparent viscosity and antioxidant activity, can promote the proliferation of lactobacillus fermentum and lactobacillus casei, and can be applied in food field as food stabilizer, food thickening agent and new prebiotic.

Description

Technical Field

[0001] This invention belongs to the field of bioengineering technology, specifically including a bioactive arabinoxylan prepared from corn husks. Background Technology

[0002] Corn is one of my country's three major crops. Corn husks, a byproduct of deep processing, account for 10-15% of the total weight of corn. The hemicellulose content in corn husks can reach about 70%, making it the most complex plant hemicellulose known to date. The hemicellulose backbone of corn husks has a very high degree of side chain transformation, containing various substituents such as arabinose, ferulic acid, and coumaric acid. Among these, arabinose has the highest content in plant tissues and can be degraded into arabinoxylan (AX). Arabicoxylan is an important soluble dietary fiber with high viscosity and high water-holding capacity, and can be widely used in the food industry as a food stabilizer and thickener.

[0003] Recent studies have shown that arabinoxylan is more readily fermented in the hindgut than oligosaccharides such as fructooligosaccharides, thus more effectively regulating hindgut health. Furthermore, arabinoxylan exhibits superior growth-promoting effects on lactic acid bacteria and Bacillus compared to fructooligosaccharides and glucose, and its proliferative effect on Bifidobacteria is significantly better than that of fructooligosaccharides. Current research primarily focuses on optimizing extraction techniques, improving extraction rates, and increasing purity of arabinoxylan from wheat bran and rice bran. Reports on the preparation of arabinoxylan with different structures and monosaccharide compositions are relatively few. However, the functional properties of arabinoxylan actually depend on its structure and monosaccharide composition. For example, low molecular weight arabinoxylan mainly affects dough water-holding capacity, while high relative molecular weight arabinoxylan can significantly affect the extensibility of raw dough. Branched substituents, on the other hand, affect the antioxidant activity and beneficial bioavailability of arabinoxylan.

[0004] Therefore, it is very important to develop arabinoxylans with new structures and monosaccharide compositions. Summary of the Invention

[0005] To address the aforementioned problems in existing technologies, the first objective of this invention is to provide a beneficial arabinoxylan. This invention utilizes the xylanase Scxyn22 to prepare arabinoxylan with a specific molecular weight distribution and monosaccharide composition, achieving a molar ratio of arabinose to xylose of 0.79. It exhibits unique apparent viscosity and antioxidant activity, promoting the proliferation of *Lactobacillus fermentum* and *Lactobacillus casei*, and can be used in the food industry as a food stabilizer, food thickener, and novel prebiotic.

[0006] A second objective of this invention is to provide a method for preparing the bioactive arabinoxylan described above. This method uses corn cellulose gum (CFG) as a raw material to prepare arabinoxylan with a specific molecular weight distribution and monosaccharide composition. The method is simple to operate, low in cost, and easy to scale up for production.

[0007] A third objective of this invention is to provide an application of the bioactive arabinoxylan described above in the field of food processing.

[0008] To achieve the first objective mentioned above, the technical solution adopted by the present invention includes:

[0009] This invention discloses a bio-friendly arabinoxylan, which is composed of xylose, arabinose, glucose, galactose, rhamnose, mannose, glucuronic acid, galacturonic acid, fucose, and ribose in a molar ratio of 104.6:82.6:21.0:16.8:8.9:5.1:4.3:1.6:1.3:1.

[0010] Furthermore, the molecular weight of the arabinoxylan is between 2.51 and 10 kDa.

[0011] In this invention, arabinoxylan with a specific molecular weight distribution and monosaccharide composition was successfully prepared using corn cellulose gum as raw material and xylanase Scxyn22. Monosaccharide composition analysis revealed that the molar ratio of arabinose to xylose can reach 0.79, which is significantly higher than the existing technology level. It exhibits unique physicochemical properties, beneficial properties, and biological activity, and can be used as a food stabilizer, food thickener, and novel prebiotic in the food industry.

[0012] To achieve the second objective mentioned above, the technical solution adopted by the present invention includes:

[0013] This invention discloses a method for preparing the arabinoxylan described above, comprising the following steps:

[0014] Corn cellulose was dissolved in a buffer solution with a pH of 4-6, xylanase Scxyn22 was added, and the reaction was carried out at 30-70℃ for 12-48 hours. After the reaction was completed, the hydrolysis product was separated and purified to obtain the final product.

[0015] Furthermore, the amount of xylanase Scxyn22 added is 30-70U of xylanase Scxyn22 per 1g of corn cellulose gum.

[0016] Furthermore, the amount of xylanase Scxyn22 added is 50U of xylanase Scxyn22 per 1g of corn cellulose gum.

[0017] The Scxyn22 used in this invention is an endoglucanase of the 11th family of glycoside hydrolases, and was prepared using the previously filed patent CN114621987A.

[0018] It should be noted that the target product arabinoxylan with this specific molecular weight distribution and monosaccharide composition can be obtained under the hydrolysis conditions provided by this invention. The only difference is the yield of the target product arabinoxylan.

[0019] Furthermore, the buffer solution includes, but is not limited to, one or more of citrate buffer, phosphate buffer, and acetate buffer.

[0020] Furthermore, the concentration of the corn cellulose gum in the buffer solution is 2-4 wt%.

[0021] Furthermore, the separation and purification of the hydrolysis products were carried out using a glucose gel Sephadex-G75 chromatography column. Those skilled in the art can also adjust the separation and purification methods according to experimental needs.

[0022] It should be noted that the corn cellulose gum mentioned in this invention is not limited to its source; it can be a directly purchased product or prepared by referring to existing publicly available technology. Different sources of corn cellulose gum do not affect the subsequent preparation of arabinoxylan. In one specific embodiment, the corn cellulose gum is prepared using the following steps:

[0023] Corn husk powder was treated sequentially with α-amylase and saccharifying enzyme to remove starch. After enzymatic hydrolysis, the mixture was filtered. NaOH, Ca(OH)2 and water were then added to the filter. The mixture was heated and centrifuged. The supernatant was collected and anhydrous ethanol was added to the supernatant to obtain the final product.

[0024] Furthermore, the mass ratio of the filter material, NaOH, and Ca(OH)2 is 50:2:1.9 to 50:10:1.9.

[0025] Furthermore, the heating reaction temperature is 95-100℃, and the reaction time is 1-2 hours.

[0026] Furthermore, when preparing corn fiber gum, it is also necessary to control the proportion of anhydrous ethanol in the mixture formed by anhydrous ethanol and supernatant, so that the anhydrous ethanol should be controlled below 70% (volume percentage). This is beneficial for removing free monosaccharides and oligosaccharides in the sample. Therefore, the volume ratio of anhydrous ethanol to supernatant should be controlled at 1.5-2.3:1.

[0027] To achieve the third objective mentioned above, the technical solution adopted by the present invention includes:

[0028] This invention discloses the application of arabinoxylan as described above as a food stabilizer, food thickener, or dietary supplement in the food processing field.

[0029] Beneficial effects of this invention:

[0030] This invention utilizes xylanase Scxyn22 to prepare arabinoxylan with a specific molecular weight distribution and monosaccharide composition. The arabinoxylan is composed of xylose, arabinose, glucose, galactose, rhamnose, mannose, glucuronic acid, galacturonic acid, fucose, and ribose in a molar ratio of 104.6:82.6:21.0:16.8:8.9:5.1:4.3:1.6:1.3:1, with a molecular weight ranging from 2.51 to 10 kDa. The molar ratio of arabinose to xylose reaches 0.79, and the degree of side chain substitution is significantly higher than in existing technologies. This arabinoxylan exhibits unique apparent viscosity and antioxidant activity, promoting the proliferation of *Lactobacillus fermentum* and *Lactobacillus casei*. It can be used as a food stabilizer, food thickener, and novel prebiotic in the food industry. Attached Figure Description

[0031] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0032] Figure 1 The gel permeation chromatography test chromatogram of Example 3 is shown;

[0033] in, Figure 1 In the middle, A represents CFG. Figure 1 In this context, B is CBAX2. Figure 1 C in the figure represents purified CBAX2.

[0034] Figure 2 The apparent viscosity changes of the hydrolysis products at different times are shown in Example 5.

[0035] Figure 3 The infrared spectra of CFG and CBAX2 in Example 6 are shown.

[0036] Figure 4 Ion chromatography analysis of the hydrolysis products at different times in Example 7 is shown;

[0037] in, Figure 4 In the equation, A represents the hydrolysis time, which is 3 hours. Figure 4 In section B, the hydrolysis time is 6 hours. Figure 4 C represents the hydrolysis time of 12 hours.

[0038] Figure 5 The growth curves of probiotics in different culture media are shown in Example 8;

[0039] in, Figure 5In the middle, A represents Lactobacillus fermentum. Figure 5 B is Lactobacillus rhamnosus. Figure 5 C in the middle represents Lactobacillus casei. Figure 5 D in the middle is Pediococcus lactis. Figure 5 E in the middle represents Lactobacillus plantarum.

[0040] Figure 6 The antioxidant activity analysis of CFG and CBAX2 in Example 9 is shown;

[0041] in, Figure 6 A represents the activity that scavenges ABTS. Figure 6 B represents the scavenging of DPPH activity. Figure 6 C represents the hydroxyl radical scavenging rate. Detailed Implementation

[0042] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further clarifies the invention. It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0043] Example 1: Extraction of corn fiber gum

[0044] 1) After drying and pulverizing the corn husks, pass them through a 60-mesh sieve to obtain corn husk powder. Weigh 50g of corn husk powder, add 500mL of distilled water, adjust the pH to 6.0, add high-temperature α-amylase, and treat in a 95℃ water bath for 30min. Then lower the water bath temperature to 55℃, add saccharifying enzyme, react for 30min, and check the starch hydrolysis using I2-KI solution. After complete hydrolysis, filter with gauze, wash the filter residue twice with distilled water, and dry at 60℃.

[0045] 2) Weigh 50g of the sample obtained in step 1), add 2g of NaOH and 1.9g of Ca(OH)2, add 500mL of distilled water, mix and react in a boiling water bath for 1h, cool the solution after reaction to room temperature, centrifuge at 6000×g for 20min and separate the supernatant.

[0046] 3) Adjust the pH of the supernatant from step 2) to 4.0, centrifuge at 10000×g for 30 min, and separate the supernatant; add 2 times the volume of anhydrous ethanol to the supernatant to obtain a white flocculent precipitate, centrifuge at 10000×g for 30 min and separate the precipitate, and freeze-dry the precipitate to obtain corn husk fiber gum.

[0047] Example 2: Preparation of arabinoxylan by hydrolysis

[0048] Our laboratory prepared xylanase Scxyn22 according to patent CN114621987A. Then, Scxyn22 was digested with EcoRI and NotI, and directly ligated into the digested pPIC9k plasmid. This was then transformed into TransI-T1 competent cells, and transformants were selected for sequencing verification. Transformants that were correctly sequenced were identified as the recombinant yeast expression plasmid pPIC9K-Scxyn22.

[0049] The recombinant expression plasmid pPIC9K-Scxyn22 was linearized with the restriction enzyme SacI and transformed into Pichia pastoris GS115 to obtain the recombinant yeast strain GS115 / pPIC9K-Scxyn22. Positive transformants were selected and transferred to 1L Erlenmeyer flasks containing 200mL BMGY medium (1% yeast extract, 2% peptone, 1% glycerol, 1.34% YNB, 0.00004% Biotin). The flasks were incubated at 30℃ and 230rpm for 36h. The fermentation broth was centrifuged at 3000×g for 5min, the supernatant was discarded, and the precipitated cells were resuspended in 200mL BMMY medium (1% yeast extract, 2% peptone, 1.34% YNB, 0.00004% Biotin, 0.5% methanol). The flasks were then incubated at 30℃ and 230rpm for 144h, with methanol added every 12h at a rate of 1% of the fermentation broth volume. After induction, the fermentation broth was centrifuged at 4℃ and 11000rpm for 10min, and the supernatant was obtained as the crude enzyme solution.

[0050] The crude enzyme solution was subjected to ammonium sulfate fractionation at 4℃, centrifuged at 11000 r / min for 10 min, and the crude enzyme precipitate was collected. The crude enzyme precipitate was dissolved in 20 mmol / L citrate buffer (pH 7.2) and dialyzed overnight at 4℃. The dialyzed enzyme solution was purified using a QSFF ion exchange column, and the eluent was collected. The eluent was the purified xylanase Scxyn22.

[0051] Using purified xylanase Scxyn22 for hydrolysis is beneficial to improving the yield of the target product, arabinoxylan.

[0052] Dissolve 3g of corn husk cellulose in 100mL of citrate buffer (pH 4.0-6.0). Add xylanase Scxyn22 at a rate of 50U per 1g of corn husk cellulose. Then, hydrolyze the mixture at 50℃ for 48h.

[0053] The hydrolysis product was separated and purified by glucose gel Sephadex-G75 chromatography to obtain corn husk arabinoxylan, which was named CBAX2.

[0054] Example 3: Molecular weight distribution of CBAX2

[0055] To further understand the arabinoxylan obtained above, the molecular weight distribution of CFG and CBAX2 was determined by gel permeation chromatography. The results are shown in Tables 1 and 2. Figure 1 The chromatographic conditions were as follows: Waters 1525 high performance liquid chromatograph, Waters 2414 differential detector, PL aquqgel-OH MIXED-H column 8μm, mobile phase 0.2M NaNO3, flow rate 1mL / min, column temperature 30℃, and sample loading volume 20μL.

[0056] Table 1. Molecular weight distribution of corn husk fiber gum

[0057] Mw(kDa) Percent (%) 500-990 3.63 300-500 27.78 200-300 29.22 100-200 26.36 50-100 7.71 30-50 2.40 25-30 0.58 10-25 2.02 8-10 0.24 7.5-8 0.06

[0058] Table 2. Molecular weight distribution characteristics of CBAX2

[0059] Mw(kDa) Percent (%) 10-25 4.69 8-10 6.05 3-8 81.87 2.51-3 6.21

[0060] Measurements showed that the molecular weight of CFG was significantly reduced after hydrolysis by Scxyn22. 83.36% of the molecules in CFG had a molecular weight distribution between 100-500 kDa, while 94.13% of the molecules in CBAX2 had a molecular weight distribution between 2.51-10 kDa.

[0061] The molecular structure characteristics of CBAX2 were analyzed using GPC software, as shown in Table 3. The dispersion coefficient (Mw / Mn) reflects the difference between the mass and structure of the substances contained in the sample; the larger the dispersion coefficient, the greater the structural difference. The dispersion coefficient of CBAX2 is 2.23, indicating that the corn husk arabinoxylan obtained by this method has good uniformity and a narrow molecular weight distribution.

[0062] Table 3. Molecular structural characteristic parameters of CBAX2

[0063] Mp(g / mol) Mn(g / mol) Mw(g / mol) Mw / Mn CBAX2 6207 5170 11510 2.23 CFG 298659 138129 245916 1.78

[0064] Example 4: Monosaccharide composition analysis of CBAX2

[0065] Monosaccharide components were determined using an Agilent 1200 chromatographic column equipped with a UV detector, and the results are shown in Table 4. The chromatographic conditions were as follows: Agilent C18 column (4.6 mm × 250 mm × 5 μm), mobile phase A was 0.1 mol / L KH₂PO₄ (pH 6.8), mobile phase B was acetonitrile, the mobile phase gradient was mobile phase A:mobile phase B = 82:18, isocratic elution was used, the flow rate was 1.0 mL / min, and the column temperature was 25 °C.

[0066] Analysis revealed that CBAX2 is composed of xylose, arabinose, glucose, galactose, rhamnose, mannose, glucuronic acid, galacturonic acid, fucose, and ribose in a molar ratio of 104.6:82.6:21.0:16.8:8.9:5.1:4.3:1.6:1.3:1. The arabinose / xylose molar ratio of the substrate CFG is 0.56, indicating a side-chain substitution degree (Ara / Xyl) of 0.56. The arabinose / xylose molar ratio in CBAX2 obtained from the hydrolysis reaction is significantly increased, reaching 0.79. This indicates that CBAX2 exhibits a high degree of branching and a complex structure, altering its physicochemical properties and biological activity.

[0067] Table 4. Monosaccharide composition of CBAX2

[0068] Monosaccharide names CBAX2(mole%) CFG(mole%) Xylose 42.31 52.84 Arabic sugar 33.41 29.51 Galactose 6.80 7.97 Rhamnose 3.60 0.66 glucose 8.50 4.67 Mannose 2.05 0.68 Glucuronic acid 1.75 1.14 Ribose 0.40 0.07 Galacturonic acid 0.65 1.39 Fucose 0.52 1.05

[0069] Example 5: Apparent viscosity change during CFG hydrolysis

[0070] The change in apparent viscosity during the hydrolysis of CFG was determined using a rotational rheometer (AR2000ex model).

[0071] A parallel plate measurement system with a diameter of 40 mm was selected. The sample stage temperature was set to 25℃, the plate spacing was 1.0 mm, and the shear rate was set from 0.1 s⁻¹. -1 Increased to 200s -1 Samples were taken at reaction times of 3h, 6h, 12h, 18h, and 24h to analyze the changes in apparent viscosity of the hydrolysis products of CFG catalyzed by xylanase Scxyn22, and to determine the apparent viscosity characteristics of the hydrolysis products at different hydrolysis times.

[0072] The test results showed that xylanase Scxyn22-catalyzed hydrolysis could reduce the apparent viscosity of CFG. Figure 2 As the hydrolysis time increases, the apparent viscosity of the hydrolysate decreases and tends to stabilize, indicating that the hydrolysate has relatively stable rheological properties. Those skilled in the art will understand that the rheological properties of arabinoxylan determine its application areas; for example, low molecular weight arabinoxylan affects the water-holding capacity of dough, while high molecular weight arabinoxylan significantly affects the extensibility of raw dough.

[0073] Example 6: Infrared Spectral Characteristics

[0074] Infrared spectroscopy was used to analyze CFG and CBAX2 samples. The KBr pellet method was employed for infrared spectroscopy determination: approximately 2-3 mg of sample and 100-600 mg of KBr were weighed at a sample-to-KBr mass ratio of 1:200, transferred to an agate mortar, and ground into a uniform powder. The powder was then transferred to a pelleting mold and pressed into a pellet for infrared spectroscopy determination. Figure 3 As shown, infrared analysis reveals that at 3397 cm⁻¹ -1 It is the absorption peak of the stretching vibration of -OH, a characteristic peak of carbohydrates, at 2930 cm⁻¹. -1 The nearby absorption peak is attributed to the CH stretching vibration, at 1609 cm⁻¹. -1 The nearby absorption peak is attributed to the C=O stretching vibration, a typical characteristic of xylan, at 1413 cm⁻¹. -1 The absorption peak is attributed to the CO stretching vibration, at 1042 cm⁻¹. -1 The absorption peak is attributed to the stretching vibration of OH.

[0075] Example 7: Reaction process for preparing oligosaccharides from CFG hydrolysis

[0076] The hydrolysis products at different reaction times were analyzed by ion chromatography. The ion chromatography instrument was a Thermo Fisher Chromeleon high-performance liquid chromatography system. The chromatographic column was a CarboPac™ PA200 (4.0×250mm, 8.5μm). The mobile phase was A (ultrapure water) and the mobile phase was D (1mol / L NaOH). The gradient elution conditions were: elution with 100% mobile phase A for 4 min, gradient elution with 0-100% mobile phase D for 25 min, and elution with 100% mobile phase D for 5 min.

[0077] With xylobiose, xylotriose, xylotetraose, xylopentose, XA 2 XX(2 3 -α-L-arabinofuranosyl-xylotetraose), A 3 X(3 2 -α-L-arabinofuranosyl-xylobiose), A 2 XX(2 3 -α-L-arabinofuranosyl-xylotriose), XA 3 XX(3 3 -α-L-arabinofuranosyl-xylotetraose), A 2+3 XX(2 3 ,3 3(-di-α-L-arabinofuranosyl-xylotriose) was used as a standard to detect the changes in hydrolysis products during the hydrolysis of CFG by xylanase Scxyn22. Figure 4 As shown, in addition to the increased content of xylobiose, xylotriose and other xylo-oligosaccharides in the xylanase hydrolysate, the content of CBAX2, which has a higher molecular weight, also showed a significant increase in the hydrolysate.

[0078] Example 8: In vitro bioavailability study of CBAX2

[0079] To analyze the beneficial viability of CBAX2, its effect on the proliferation of Lactobacillus fermentum, Lactobacillus rhamnosus, Lactobacillus casei, Pediococcus acidilactici, and Lactobacillus plantarum was tested.

[0080] Prepare MRS basal culture medium (1L): 10g beef extract, 10g tryptone, 5g yeast powder, 5g anhydrous sodium acetate, 0.1g MgSO4·7H2O, 0.05g MnSO4·H2O, 2g diammonium hydrogen citrate, 2.6g K2HPO4·3H2O, 1mL Tween-80, and adjust the pH to 6.8±0.2.

[0081] Preparation of MRS-oligosaccharide medium: Add 2% CFG and 2% CBAX2 as carbon sources to the prepared MRS basic medium.

[0082] Preparation of MRS-glucose medium: Add 2% glucose as a carbon source to the prepared MRS basal medium.

[0083] Various probiotics (Lactobacillus fermentum, Lactobacillus rhamnosus, Lactobacillus casei, Pediococcus lactis, and Lactobacillus plantarum, one strain at a time) were fermented and cultured using MRS basal medium, MRS-glucose medium, and MRS-oligosaccharide medium. MRS-glucose medium (G) and MRS basal medium (CK) were used as control groups. Growth curves (OD 600nm) were measured to analyze the utilization of oligosaccharides with different structures by various probiotics.

[0084] The inoculum size for each probiotic was 0.5%, and fermentation was carried out at 37℃ for a total of 48 hours. Fermentation products were collected at 0h, 12h, 24h, 36h, and 48h for subsequent analysis. Results are as follows: Figure 5As shown, when the five probiotic strains were cultured using CFG and CBAX2 as carbon sources, their growth rate and cell density were lower than those on MRS-glucose medium using glucose as the carbon source. *Lactobacillus fermentum* and *Lactobacillus casei* showed better growth when cultured with CBAX2 as the carbon source than on MRS basal medium without a carbon source, indicating that these two strains can utilize some CBAX2 as a carbon source for growth, while the addition of CFG inhibited their growth. This suggests that arabinoxylan, as a functional polysaccharide, has important physiological activities such as promoting probiotic growth and regulating intestinal flora; however, the molecular size and structural composition of arabinoxylan affect its probiotic activity.

[0085] Example 9: Antioxidant Activity of CBAX2

[0086] The DPPH scavenging activity, ABTS scavenging activity, and hydroxyl radical scavenging rate of CFG and CBAX2 were investigated. The results are shown in [reference needed]. Figure 6 Both CFG and CBAX2 exhibited high ABTS scavenging activity within a concentration range of 4-10 mg / mL, with minimal differences between them. The DPPH scavenging activities of both CFG and CBAX2 within the 2-10 mg / mL concentration range were positively correlated with concentration, with CBAX2 showing higher DPPH scavenging activity than CFG. The hydroxyl radical scavenging rates of both CFG and CBAX2 were positively correlated with concentration throughout the entire test concentration range, increasing with increasing concentration within the 2-10 mg / mL range. However, the rate of increase in hydroxyl radical scavenging rates differed between the two, with CBAX2 showing a higher rate of increase than CFG. At a concentration of 10 mg / mL, the hydroxyl radical scavenging rates of CFG and CBAX2 were 13.32% and 26.73%, respectively.

[0087] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A bioactive arabinoxylan, characterized in that, The arabinoxylan is composed of xylose, arabinose, glucose, galactose, rhamnose, mannose, glucuronic acid, galacturonic acid, fucose, and ribose in a molar ratio of 104.6:82.6:21.0:16.8:8.9:5.1:4.3:1.6:1.3:

1. The molecular weight of the arabinoxylan is between 2.51 and 10 kDa; The preparation of the arabinoxylan includes the following steps: Corn cellulose gum was dissolved in a buffer solution with a pH of 4-6, xylanase Scxyn22 was added, and the reaction was carried out at 30-70 °C for 12-48 h. After the reaction was completed, the hydrolysis product was separated and purified to obtain the product. The amount of xylanase Scxyn22 added is 30-70 U of xylanase Scxyn22 per 1 g of corn cellulose gum; The corn fiber gum was prepared according to the following steps: Corn husk powder was treated sequentially with α-amylase and saccharifying enzyme. After enzymatic hydrolysis, the mixture was filtered. NaOH, Ca(OH)2 and water were then added to the filter. The mixture was heated and centrifuged. The supernatant was collected and anhydrous ethanol was added to the supernatant to obtain the final product.

2. The method for preparing arabinoxylan as described in claim 1, characterized in that, Includes the following steps: Corn cellulose gum was dissolved in a buffer solution with a pH of 4-6, xylanase Scxyn22 was added, and the reaction was carried out at 30-70 °C for 12-48 h. After the reaction was completed, the hydrolysis product was separated and purified to obtain the product. The amount of xylanase Scxyn22 added is 30-70 U of xylanase Scxyn22 per 1 g of corn cellulose gum; The corn fiber gum was prepared according to the following steps: Corn husk powder was treated sequentially with α-amylase and saccharifying enzyme. After enzymatic hydrolysis, the mixture was filtered. NaOH, Ca(OH)2 and water were then added to the filter. The mixture was heated and centrifuged. The supernatant was collected and anhydrous ethanol was added to the supernatant to obtain the final product.

3. The preparation method according to claim 2, characterized in that, The amount of xylanase Scxyn22 added is 50 U of xylanase Scxyn22 per 1g of corn cellulose gum.

4. The preparation method according to claim 2, characterized in that, The buffer solution is selected from one or more of citrate buffer, phosphate buffer, and acetate buffer.

5. The preparation method according to claim 2, characterized in that, The concentration of the corn cellulose gum in the buffer solution is 2-4 wt%.

6. The preparation method according to claim 5, characterized in that, The volume ratio of anhydrous ethanol to supernatant is 1.5-2.3:

1.

7. The use of arabinoxylan as described in claim 1 or arabinoxylan prepared by any one of the preparation methods described in claims 2-6 as a food stabilizer, food thickener or dietary supplement in the food processing field.

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