A modified akebia pectin, preparation method and application thereof

Abstract

The present invention provides a modified akebia pectin, a preparation method and an application thereof, and belongs to the technical field of biomacromolecule processing. The present invention degrades and modifies akebia pectin through specific enzymolysis and dielectric barrier discharge plasma treatment steps, thereby overcoming the problem that the degradation and modification method of akebia pectin in the prior art has poor effect. The modified akebia pectin obtained by the degradation and modification method of akebia pectin provided by the present invention can achieve good antibacterial effects on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, successfully achieving a significant change in the biological activity of akebia pectin polysaccharides, and has important practical significance for developing akebia pectin resources and enhancing its utilization value.

Description

Technical Field

[0001] The invention relates to the technical field of biomacromolecule processing, and in particular to a modified Akebia trifoliata pectin, a preparation method and application thereof. Background Art

[0002] Akebia trifoliata is also known as "August Melon" or "August Explosion". Its fruit is large and thick, with juicy and sweet flesh. It has high nutritional and medicinal value and is a fruit that has developed rapidly in the Yangtze River Basin in recent years. Akebia trifoliata is particularly widely distributed in Guizhou Province. According to incomplete statistics, its wild resources amount to more than one million mu. The peel accounts for more than 69% of the total weight of the fruit and has an extremely low edible rate. How to reasonably utilize and develop Akebia trifoliata resources is a major issue related to the healthy and sustainable development of my country's medicinal wild resources and related industries. The pectin content in the peel of Akebia trifoliata is high and has certain biological activity, but the extracted pectin has no antibacterial or bactericidal effect due to its large molecular weight and high degree of esterification (Zhang Mengqin, Tian Ye, Li Xingping, et al. Study on the antibacterial effect of pectin from the peel of Akebia trifoliata [J]. Anhui Agricultural Science, 2009 (17): 3.), which seriously hinders its bioavailability.

[0003] At present, the main methods for pectin degradation and modification are acid-thermal degradation, ultrasonic degradation, enzymatic degradation, etc. However, the above degradation methods can only reduce the molecular weight of Akebia trifoliata pectin, and cannot achieve good improvement on the biological activity of Akebia trifoliata pectin. Summary of the invention

[0004] The object of the present invention is to provide a modified Akebia trifoliata pectin, a preparation method and application thereof, so as to solve the problem that the degradation and modification method of Akebia trifoliata pectin in the prior art has poor effect.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a degradation and modification method of Akebia trifoliata pectin, comprising the following steps:

[0007] The Akebia trifoliata pectin solution was subjected to enzymatic hydrolysis and dielectric barrier discharge plasma treatment in sequence to obtain modified Akebia trifoliata pectin.

[0008] Preferably, the concentration of the Akebia trifoliata pectin solution is 0.3-0.8 g / L.

[0009] Preferably, the enzymatic hydrolysis uses pectinase, and the added amount of the pectinase is 70 to 90 U / g.

[0010] Preferably, the enzymatic hydrolysis temperature is 40-60° C., and the enzymatic hydrolysis time is 1.5-2.5 h.

[0011] Preferably, the voltage of the dielectric barrier discharge plasma treatment is 15-25V.

[0012] Preferably, the dielectric barrier discharge plasma treatment time is 10 to 20 minutes.

[0013] The invention also provides modified akebia pectin prepared by the degradation and modification method of the akebia pectin.

[0014] The present invention also provides an application of the modified Akebia trifoliata pectin in the preparation of antibacterial products.

[0015] Technical effects and advantages of the present invention:

[0016] The modified Akebia trifoliata pectin obtained by the degradation and modification method of Akebia trifoliata pectin provided by the present invention can achieve good antibacterial effects on Escherichia coli, Staphylococcus aureus and Bacillus subtilis, successfully achieves a significant change in the biological activity of Akebia trifoliata pectin polysaccharide, and has important practical significance for developing Akebia trifoliata pectin resources and enhancing its utilization value. DETAILED DESCRIPTION

[0017] The present invention provides a degradation and modification method of Akebia trifoliata pectin, comprising the following steps:

[0018] The Akebia trifoliata pectin solution was subjected to enzymatic hydrolysis and dielectric barrier discharge plasma treatment in sequence to obtain modified Akebia trifoliata pectin.

[0019] In the present invention, the Akebia trifoliata pectin solution is preferably prepared from Akebia trifoliata pectin dry powder, the Akebia trifoliata pectin solution preferably uses distilled water as a solvent, and the concentration of the Akebia trifoliata pectin solution is preferably 0.3-0.8 g / L, and more preferably 0.4-0.6 g / L.

[0020] In the present invention, the Akebia trifoliata pectin solution is subjected to enzymatic hydrolysis, and the enzymatic hydrolysis preferably uses pectinase, and the added amount of the pectinase is preferably 70-90 U / g, and more preferably 75-85 U / g; the enzymatic hydrolysis temperature is preferably 40-60°C, and more preferably 45-55°C; the enzymatic hydrolysis time is preferably 1.5-2.5h, and more preferably 1.8-2.2h.

[0021] In the present invention, the Akebia trifoliata pectin solution is subjected to dielectric barrier discharge plasma treatment after enzymatic hydrolysis, and the voltage of the dielectric barrier discharge plasma treatment is preferably 15 to 25 V, more preferably 18 to 22 V; the time of the dielectric barrier discharge plasma treatment is preferably 10 to 20 min, more preferably 14 to 18 min.

[0022] The present invention also provides a modified Akebia pectin prepared by the above-mentioned degradation modification method of Akebia pectin and its application in the preparation of antibacterial products, wherein the product preferably uses the modified Akebia pectin of the present invention as the only active ingredient; the product preferably also includes an auxiliary material, and the present invention does not specifically limit the type of the auxiliary material, and the conventional product auxiliary materials in the field can be used; the product of the present invention can be an external product or an oral product, and the product dosage form is preferably a solution, a lotion, a spirit, an emulsion, a cold cream preparation, a suspension, a gel preparation, an ointment, a spray, an aerosol, a powder spray, a plaster or a film preparation, etc. In the present invention, the product includes a carrier, and the carrier is preferably a matrix, a diluent, a lubricant, a preservative, etc.

[0023] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0024] Sources of reagents used:

[0025] Escherichia coli, Staphylococcus aureus, and Bacillus subtilis were purchased from China General Microbiological Culture Collection Center.

[0026] Pectinase was purchased from Shanghai Bangcheng Chemical Co., Ltd.;

[0027] The low-temperature plasma experimental equipment was purchased from Nanjing Suman Plasma Technology Co., Ltd.

[0028] Example 1

[0029] 20 g of Akebia trifoliata pectin was prepared into a 0.5 g / L pectin solution, 30 mL of the pectin solution was added with 80 U / g of pectinase, and enzymolysis was performed at 50° C. for 2 h. The enzymolysis solution was placed in a plasma reaction vessel and treated at 20 V for 15 min to obtain the degraded and modified Akebia trifoliata pectin.

[0030] Example 2

[0031] 20 g of Akebia trifoliata pectin was prepared into a 0.3 g / L pectin solution, 30 mL of the pectin solution was added with pectinase at an addition amount of 90 U / g, and the solution was enzymolyzed at 52°C for 1.5 h. The enzymolysis solution was placed in a plasma reaction vessel and treated at 25 V for 10 min to obtain the degraded and modified Akebia trifoliata pectin.

[0032] Example 3

[0033] 20 g of Akebia trifoliata pectin was prepared into a 0.8 g / L pectin solution, 30 mL of the pectin solution was added with pectinase at an addition amount of 70 U / g, and enzymolysis was performed at 48°C for 2.5 h. The enzymolysis solution was placed in a plasma reaction vessel and treated at 30 V for 5 min to obtain the degraded and modified Akebia trifoliata pectin.

[0034] Comparative Example 1

[0035] Take 20g of Akebia trifoliata pectin to prepare a 0.5g / L pectin solution, take 30mL of the pectin solution, add pectinase at an addition amount of 80U / g, and perform enzymolysis at 50°C for 2h to obtain the Akebia trifoliata pectin solution.

[0036] Comparative Example 2

[0037] Take 20g of Akebia trifoliata pectin to prepare a 0.5g / L pectin solution, take 30mL of the pectin solution and put it into a plasma reaction container, treat it at 20V voltage for 15min, and obtain the Akebia trifoliata pectin solution.

[0038] Comparative Example 3

[0039] Take 20g of Akebia trifoliata pectin to prepare a 5g / L pectin solution, take 30mL of the pectin solution, add pectinase at an addition amount of 80U / g, and enzymolyze at 50°C for 2h. Put the enzymolysis solution into a plasma reaction container and treat it at 20V voltage for 15min to obtain the Akebia trifoliata pectin solution.

[0040] Comparative Example 4

[0041] Take 20g of Akebia trifoliata pectin to prepare a 0.5g / L pectin solution, take 30mL of the pectin solution, add pectinase at an addition amount of 50U / g, and enzymolyze at 50℃ for 1h. Put the enzymolysis solution into a plasma reaction container and treat it at 20V voltage for 15min to obtain the Akebia trifoliata pectin solution.

[0042] Comparative Example 5

[0043] Take 20g of Akebia trifoliata pectin to prepare a 0.5g / L pectin solution, take 30mL of the pectin solution, add pectinase at an addition amount of 100U / g, and perform enzymolysis at 50°C for 5h. Put the enzymolysis solution into a plasma reaction container and treat it at 20V for 15min to obtain the Akebia trifoliata pectin solution.

[0044] Comparative Example 6

[0045] Take 20g of Akebia trifoliata pectin to prepare a 0.5g / L pectin solution, take 30mL of the pectin solution, add pectinase at an addition amount of 80U / g, and enzymolyze at 50°C for 2h. Put the enzymolysis solution into a plasma reaction container and treat it at 10V voltage for 5min to obtain the Akebia trifoliata pectin solution.

[0046] Comparative Example 7

[0047] Take 20g of Akebia trifoliata pectin to prepare a 0.5g / L pectin solution, take 30mL of the pectin solution, add pectinase at an addition amount of 80U / g, and enzymolyze at 50°C for 2h. Put the enzymolysis solution into a plasma reaction container and treat it at 50V for 30min to obtain the Akebia trifoliata pectin solution.

[0048] Comparative Example 8

[0049] Take 20g of Akebia trifoliata pectin and prepare a 0.5g / L pectin solution.

[0050] Experimental Example 1 Antibacterial Activity Detection

[0051] Escherichia coli, Staphylococcus aureus and Bacillus subtilis were used as bacterial species, the diameter of the inhibition zone was used as an indicator, and the pectin raw material was used as a positive control. The agar pore diffusion method (refer to Li Xiulan, Dai Zhuying, Zhang Shuangquan. Comparison of the activity of antimicrobial peptides measured by agarose pore diffusion method and turbidimetry and their correlation [J]. Journal of Nanjing Normal University: Natural Science Edition, 1998, 21 (2): 3) was used to determine the antibacterial activity of the pectin degradation products of Examples 1 to 3 and Comparative Examples 1 to 8. Three parallel experiments were performed in each group, and the results of the inhibition zone diameter test were recorded and the average of the three times was taken, as shown in Table 1 below:

[0052] Table 1 Antibacterial activity test results

[0053]

[0054] It can be seen from the results that the degraded and modified Akebia trifoliata pectin solution provided by the present invention can achieve good antibacterial effects on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, and successfully achieves the modification of Akebia trifoliata pectin. It can be seen from the comparative example results that the modified Akebia trifoliata pectin obtained by enzymolysis or dielectric barrier discharge plasma treatment alone has a poor antibacterial effect, and the pectinase concentration is too small, the enzymolysis time is too short, the pectin solution concentration is too large, and the dielectric barrier discharge plasma treatment intensity is too small, which will lead to inadequate degradation and too much residual high molecular weight oligosaccharides; excessive enzymolysis and excessive dielectric barrier discharge plasma treatment intensity will lead to excessive degradation, excessive monosaccharide content in the solution, and poor biological activity.

[0055] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A degradation and modification method for Akebia trifoliata pectin, characterized in that: The following steps are included: The Akebia trifoliata pectin solution is subjected to enzymatic hydrolysis and dielectric barrier discharge plasma treatment in sequence to obtain modified Akebia trifoliata pectin; The concentration of the Akebia trifoliata pectin solution is 0.3-0.8 g / L; The enzymatic hydrolysis uses pectinase, and the added amount of the pectinase is 70-90 U / g; The enzymatic hydrolysis temperature is 40-60°C, and the enzymatic hydrolysis time is 1.5-2.5h; The voltage of the dielectric barrier discharge plasma treatment is 15 to 25 V; The dielectric barrier discharge plasma treatment time is 10 to 20 minutes.

2. The modified Akebia pectin prepared by the degradation and modification method of Akebia pectin according to claim 1.

3. The use of the modified Akebia trifoliata pectin according to claim 2 in the preparation of antibacterial products, characterized in that: The antibacterial product is a product that resists Escherichia coli, Staphylococcus aureus or Bacillus subtilis.

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