CN108570487B

CN108570487B - Method for increasing content of fructosyl mangiferin in plant extract

Info

Publication number: CN108570487B
Application number: CN201710257146.8A
Authority: CN
Inventors: 洪怡芳; 傅威昌; 蔡孟贞; 赖进此
Original assignee: Food Industry Research and Development Institute
Current assignee: Food Industry Research and Development Institute
Priority date: 2017-03-08
Filing date: 2017-04-19
Publication date: 2021-07-27
Anticipated expiration: 2037-04-19
Also published as: TWI626313B; CN108570487A; TW201833327A

Abstract

Use of lactic acid bacteria (Lactobacillus plantarum) with accession number BCRC 11697 for biotransformation reaction of mangiferin and glycosyl donor to produce fructosyl mangiferin. One embodiment of the use includes a method for increasing the content of fructosylation mangiferin in mango peel extract.

Description

Method for increasing content of fructosyl mangiferin in plant extract

The present application claims priority to taiwan patent application 106107637 entitled "method of increasing the content of fructosylated mangiferin in plant extracts" filed 2017, 3, 8, which is hereby incorporated by reference in its entirety.

Technical Field

The invention relates to a method for increasing the content of fructosyl mangiferin in mango peel extract by using lactic acid bacteria (Lactobacillus plantarum) with the preservation number of BCRC 11697, and application of the lactic acid bacteria (Lactobacillus plantarum) with the preservation number of BCRC 11697 in biotransformation reaction of mangiferin and glycosyl donor to generate the fructosyl mangiferin.

Background

Mangiferin is a carbon ketoside of tetrahydroxypyridone, belongs to a flavonoid compound of bisphenopyridone, and exists in various plants, such as mango trees, almond trees, northeast gentian, rhizoma anemarrhenae and the like. The molecular formula of mangiferin is as follows: c₁₉H₁₈O₁₁Molecular weight: 422.3. mangiferin has various biological activities and pharmacological actions, such as antioxidation, anti-tumor, immunoregulation, anti-diabetes, anti-inflammation, etc. (Deng Jia, Li lan mushroom, Changchun Chinese medicine university, 2008, 24(4): 463 and 464.).

Although mangiferin has wide pharmacological activity, the solubility of mangiferin is poor, the development of the preparation of mangiferin is severely limited, and the solubility and the bioavailability of mangiferin need to be improved for convenient application.

For natural active ingredients with complex structures, the structural modification by chemical synthesis has the defects of low yield, poor reaction specificity, a plurality of byproducts and the like, and particularly, some reactions are difficult to realize by chemical means at present, but the defects of chemical synthesis can be made up by a biotransformation technology. Cantagrel et al (publication No. FR 2882762A 1) glycosylate mangiferin with glucosyltransferases from two strains of Leuconostoc mesenteroides to obtain glucosyl-beta- (1,6) -mangiferin (CASRN: 908570-23-0) when mangiferin is glycosyl acceptor and sucrose is glycosyl donor. When the Leuconostoc mesenteroides NRRL B-1299 strain is used as a biocatalyst, the glycosylation yield is 25 percent under the conditions of 0.4g/L mangiferin and 40g/L sucrose; when Leuconostoc mesenteroides NRRL 521-F strain is used as a biocatalyst, the glycosylation yield is 28% under the conditions of 0.4g/L mangiferin and 40g/L sucrose.

Chinese patent application publication No. CN 102863484A discloses a method for preparing fructosyl mangiferin, which comprises adding a substance with fructosyl hydrolase activity into a transformation liquid containing mangiferin to carry out biotransformation reaction, so that the mangiferin is transformed into the fructosyl mangiferin, wherein the transformation liquid contains mangiferin and glycosyl donor, the substance with fructosyl hydrolase activity is a fermentation liquid which is derived from Arthrobacter nicotianae and has the preservation number of CCTCC M2010164.

Purified mangiferin was used in the aforementioned patent applications of french publication No. FR 2882762 a1 and chinese publication No. CN 102863484 a for the fructosylation of mangiferin.

Disclosure of Invention

The invention mainly aims to provide a method for directly carrying out biotransformation reaction by taking mangiferin-containing plant extract as a substrate so as to convert the mangiferin into fructosyl mangiferin.

Another objective of the invention is to provide a suitable microorganism for carrying out a biotransformation reaction directly using mangiferin-containing plant extract as a substrate to convert the mangiferin into fructosyl mangiferin.

The invention also aims to provide a suitable microorganism and a method for improving the content of fructosyl mangiferin in mango peel extracting solution.

The invention relates to a method for increasing the content of fructosyl mangiferin in plant extract, which comprises the following steps:

providing a plant extract containing mangiferin; and

adding a glycosyl donor into the plant extract, and performing biotransformation reaction in the presence of a substance with fructosyl hydrolase activity to convert the mangiferin into fructosyl mangiferin, wherein the substance with fructosyl hydrolase activity is produced by fermentation of Lactobacillus (Lactobacillus plantarum) with accession number of BCRC 11697.

Preferably, the plant extract is mango peel extract.

Preferably, the glycosyl donor is sucrose or glucose. More preferably, the glycosyl donor is sucrose.

Preferably, the lactic acid bacterium (Lactobacillus plantarum) with the accession number BCRC 11697 is added to the plant extract.

Preferably, a fermentation broth of the lactic acid bacterium (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

Preferably, a fermentation supernatant of the lactic acid bacterium (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

Preferably, fructosylase purified from a fermentation supernatant of the lactic acid bacterium (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

Preferably, the biotransformation reaction is carried out in a lactic acid bacteria culture medium at 20-40 deg.C and no stirring or no more than 400rpm for 0.5-96 hr, and based on 100mL of the culture medium, the amount of the glycosyl donor is 1-20 g, the amount of the plant extract is 1-60mL, and the amount of the lactic acid bacteria is 10⁵～10⁷CFU/mL。

The invention provides an application of Lactobacillus (Lactobacillus plantarum) with a preservation number of BCRC 11697 in biotransformation reaction of mangiferin and glycosyl donor to generate fructosyl mangiferin.

The invention provides an application of a fermentation liquid of Lactobacillus (Lactobacillus plantarum) with a preservation number of BCRC 11697 in biotransformation reaction of mangiferin and glycosyl donor to generate fructosyl mangiferin.

The invention provides an application of mangiferin and glycosyl donor in biotransformation reaction of mangiferin and glycosyl donor by using a fermentation supernatant of Lactobacillus (Lactobacillus plantarum) with a preservation number of BCRC 11697 to generate fructosyl mangiferin.

The invention provides a use of a fructosylation enzyme purified from a fermentation supernatant of lactic acid bacteria (Lactobacillus plantarum) with the accession number BCRC 11697 for carrying out a bioconversion reaction of mangiferin and a glycosyl donor to produce fructosylation mangiferin.

Drawings

Fig. 1 is an ultraviolet absorption spectrum of a fructosyl mangiferin standard substance at different wavelengths.

FIG. 2 shows the ultraviolet absorption spectra of the supernatant after the conversion with Lactobacillus plantarum lactic acid bacteria and the centrifugation removal of the bacteria according to the method of the invention at different wavelengths.

FIG. 3 is a liquid chromatography mass spectrometry (LC-MS) spectrum of a fructosyl mangiferin standard.

FIG. 4 is a LC-MS spectrum of supernatant after the Lactobacillus plantarum Lactobacillus is transformed and centrifuged to remove the bacteria according to the method of the present invention.

Figure 5 shows the effect of different glycosyl donors on the conversion of mangiferin to fructosylated mangiferin by strains of the invention.

Figure 6 shows the results of comparing the sucrose glycosyl at different levels (ratios) to the efficiency of the strains of the invention to convert mangiferin to fructosylated mangiferin.

Detailed Description

A preferred embodiment accomplished in accordance with the present invention comprises a method for increasing the fructosylation mangiferin content in a mango peel extract, essentially comprising adding a glycosyl donor to the mango peel extract, performing a bioconversion reaction in the presence of a substance having fructosyl converting enzyme activity, to convert mangiferin contained in the mango peel extract to fructosylation mangiferin, wherein the substance having fructosyl converting enzyme activity is produced by fermentation of lactic acid bacteria (Lactobacillus plantarum) deposited under accession number BCRC 11697. The method can enable mango peel to be glycosylated with mangiferin more efficiently, so that the problem that when mango is made into fruit juice, dried mango or canned mango pulp during mango production, the mango peel is out of the place, environmental pollution is reduced, and the purposes of full fruit utilization and mango economic value improvement are achieved.

A suitable method for preparing mango peel extract for use in the present invention includes (but is not limited to) the following steps: cleaning and crushing mango peel;

then, using celloferment (Cellulase) to perform homogenization treatment at room temperature to 50 ℃ for 60-180 minutes; drying at 60 deg.C to remove water, and pulverizing into powder; mixing the powder with a polar solvent at a ratio of 1: 5-1: 20g/mL, extracting at 50 deg.C preferably under ultrasonic oscillation such as 125-500W/L for 60 min at room temperature to 50 deg.C, and removing the polar solvent to obtain Mangiferin-containing pericarp extract.

Suitable polar solvents are, for example, water, C1-C3 alcohols and mixtures thereof, preferably ethanol in water, for example 50% (v/v) ethanol.

The mango peel extracting solution is a matrix material source for transforming mangiferin by using microorganisms, and the invention uses Cellulase (cellulose) or other enzymes capable of decomposing the wall of a plant cell to promote the extraction benefit of substances in the cell. In addition, ultrasonic oscillation is adopted during extraction, so that the extraction effect of flavonoid substances in the mango peel can be further improved. According to the method, parameters such as solvent ratio, ultrasonic power, extraction time and the like are discussed, 50% (v/v) ethanol water solution is obtained, the ultrasonic power is 500W/L, the extraction is carried out for 60 minutes at 50 ℃, and mango polyphenol with high content and mango peel extract rich in mangiferin can be obtained. In a preferred embodiment, the content of fructosyl mangiferin in the mango peel extract is 18 μ g/mL by HPLC quantitative analysis.

One suitable glycosyl donor for use in the present invention includes, but is not limited to, sucrose, glucose and fructose, with sucrose or glucose being preferred and sucrose being most preferred.

Preferably, a fermentation supernatant of the lactic acid bacterium (Lactobacillus plantarum) deposited under the accession number BCRC 11697 in the biotransformation reaction of the method of the present invention is added to the mango peel extract. A suitable medium formulation for the lactic acid bacteria of BCRC 11697 comprises: 2-80 g/L glucose, 5-50 g/L peptone and KH₂PO₄ 0.4～4g/L，MgSO₄·7H₂O 0.05～1.0g/L，MnSO₄·H₂0.01-0.1 g/L of O and 6-8 of pH.

The process of the present invention preferably further comprises purifying the product of the biotransformation reaction with increased fructosyl mangiferin content, for example by means of resin purification to obtain the aqueous fraction thereof. The water phase can be used as antioxidant directly or after concentrating, and can be added into cosmetic such as sunscreen emulsion or cosmetic. Optionally, the purified fructosylated mangiferin can also be obtained by separating the fructosylated mangiferin from the liquid fraction by known purification methods.

Examples

Materials and methods

1. Culture medium formula and strain culture

(1) Lactobacillus culture medium (MRS medium)

MRS culture medium formula: sequentially adding 1g of monthly peptone (Proteose peptone) No.3, 1g of Beef extract (Beef extract), 0.5g of Yeast extract (Yeast extract), 2g of glucose (Dextrose), 0.1g of Tween 80 surfactant, 0.2g of Ammonium citrate (Ammonium citrate), 0.5g of CH₃COONa, 10mg MgSO₄·7H₂O、5mg MnSO₄·H₂O、0.2g K₂HPO₄Then, the volume was adjusted to 100mL by adding water, and the pH was adjusted to 6.5 and then autoclaved. After the strain is activated in the culture medium, the inoculation amount of the strain is 10 percent of the volume of the culture medium. The growth temperature was 37 ℃ and pH 6.5, and the OD of the bacterial solution was obtained by static culture (0rpm)₆₀₀When 10 days have elapsed, the cells were centrifuged to remove the cells to obtain a supernatant.

(2) Bacteria culture medium (Nutrient medium)

0.3g of Beef extract (Beef extract), 0.5g of peptone (peptone) were added in this order, followed by addition of water to make the volume 100mL, adjustment of the pH to 7.0 and autoclaving. After the strain is activated in the culture medium, the inoculation amount of the strain is 10 percent of the volume of the culture medium. The growth temperature is 26 ℃, pH 7.0, 100rpm culture, OD of bacteria liquid₆₀₀When 10 days have elapsed, the cells were centrifuged to remove the cells to obtain a supernatant.

(3) Yeast culture medium (YPD medium)

2g of peptone (peptone), 2g of glucose (Dextrose), and 1g of Yeast extract (Yeast extract) were sequentially added, followed by autoclaving after supplementing water to make the volume 100 mL. After the strain is activated in the culture medium, the inoculation amount of the strain is 10 percent of the volume of the culture medium. The growth temperature is 25 ℃, pH 7.0, 100rpm culture, OD of bacterial liquid₆₀₀When 10 days have elapsed, the cells were centrifuged to remove the cells to obtain a supernatant.

(4) Filamentous fungus culture medium (malt extract)

2.0g of Glucose (Glucose), 1.0g of peptone (peptone) and 2.0g of wort (Malt extract) were added in this order, followed by autoclaving after adding water to make the volume 100 mL. After the strain is activated in the culture medium, the inoculation amount of the strain is 10 percent of the volume of the culture medium. Culturing at 24-30 deg.C, pH 7.0 and 100rpm to obtain bacterial liquid OD₆₀₀When 10 days have elapsed, the cells were centrifuged to remove the cells to obtain a supernatant.

2. Preparation of mango peel extract

Cleaning and crushing mango peel, adding Cellulase (cellulose) according to the proportion of 2% (W/W), carrying out hydrolysis reaction for 180 minutes at 50 ℃, drying in a 60 ℃ oven to remove water, homogenizing and crushing into mango peel powder, carrying out an ultrasonic-assisted extraction process under the conditions of 50% (v/v) ethanol, a material-liquid ratio of 1:5, an ultrasonic power of 500W/L, an ultrasonic frequency of 40Hz and an extraction temperature of 50 ℃, extracting for 60 minutes, and removing ethanol in a 60 ℃ vacuum oven to obtain a mangiferin-containing peel extract.

3. Fructosylation mango biotransformation reaction:

adding the bacterial liquid, the mango peel extracting solution and an aqueous solution of a glycosyl donor into water or Phosphate Buffered Saline (PBS), and carrying out biotransformation reaction at 37 ℃ to convert mangiferin into fructosyl mangiferin, wherein the reaction time is 96 hours. The addition amount of the bacterial liquid is 10% of the volume of the whole conversion reaction liquid, the addition amount of the mango peel extracting solution is 10% of the volume of the whole conversion reaction liquid, and the addition amount of the water solution of the glycosyl donor is 0-20 g glycosyl (0-20 w/v%) in each 100mL of the conversion reaction liquid. Analyzing the content of the fructosyl mangiferin by using a high performance liquid chromatography.

The above biotransformation reaction was repeated except that the above-mentioned bacterial solution was not added, and data of a control group for comparison was obtained.

4. High Performance Liquid Chromatography (HPLC) quantification of fructosylated mangiferin

Precisely weighing 1mg of a Fructosylated mangiferin (glycosylated mangiferin) standard product, dissolving the product with 50% ethanol, and preparing 1mL of a reference solution containing 0.01-1 mg of the product. The test sample was a liquid after completion of the conversion reaction, centrifuged at 8000rpm for 5 minutes, the supernatant was collected, and 1mL of the sample solution was subjected to HPLC Atlantis T3 column (C18,4.6mm in diameter. times.250 mm,5 μm in diameter), the mobile phase solution was acetonitrile/l% glacial acetic acid solution (15:85), the reaction temperature was 25 ℃, the flow rate was set to 1.0mL/min, the detector wavelength was set to 254nm, and the injection sample volume was 20 μ l. The sample was taken out with a syringe, filtered with 0.22um PVDF, and subjected to HPLC quantitative analysis (guolinling, zuo, liu wei, koreant, billow, 2013, measurement of mangiferin content in mango leaves, 32 (1): 43-45, university of tianjin chinese medicine).

5. Liquid chromatography-mass spectrometry (LC-MS) identification of fructosyl mangiferin

A ZORBAX Eclipse XDB-C18Narrow Bore RR column (2.1X150mm,3.5 μm) was used. The mobile phases were 0.02% aqueous formic acid and 0.02% methanoic acid, respectively, with flow rates set at 0.2 ml/min. The elution (elution) procedure was as follows:

time (min.)	0.02% aqueous formic acid (%)	0.02% formic acid methanol solution (%)
			0	95	5
2.5	95	5
			50	0	100
70	0	100

The spectra were obtained using a Micromass ZQ mass spectrometer with electrospray ionization (ESI-MS) at Cone voltages of 10V, 15V, 20V, 35V, 50V.

Results and discussion

1. Screening of strains with the potential to convert mangiferin to fructosyl mangiferin

Potential strains with fructosylase activity (beta-fructofuranosidase and fructosyl transferase) or Tyrosinase (Tyrosinase) inhibition activity are preliminarily screened from lactic acid bacteria, yeasts and filamentous fungi in a biological resource storage and research center (BCRC) online catalog of the institute of food industry development of the financial group legal (Taiwan, New bamboo city), and the potential strains respectively comprise 19 potential strains of 2 strains of bacteria, 1 strain of yeasts, 10 strains of lactic acid bacteria and 6 strains of filamentous fungi. The strains were activated as described above, subjected to biotransformation reaction, and analyzed for their fructosyl mangiferin content by high performance liquid chromatography, and the fruits are listed in Table one. From the results in the table, it can be seen that four of them have potential, 2 strains of the bacteria Arthrobacter nicotinoide BCRC 11219, Arthrobacter globiformis BCRC 10598, 1 strain of the yeast Saccharomyces cerevisiae BCRC 20855, and 1 strain of the lactic acid bacterium Lactobacillus plantarum BCRC 11697, respectively. Based on the industrial applicability, GRAS strains and those with high fructosyl mangiferin content are used as targets, and therefore, Lactobacillus plantarum is screened as a potential strain for the invention.

TABLE I screening of potential strains for converting mangiferin into fructosyl mangiferin

Note: not measured n.d ═ d ═

2. Analysis of the ability of different strains of Lactobacillus plantarum to transform into fructosylated mangiferin

Collecting different L.plantarum strains, namely L.plantarum BCRC 11697, BCRC 12327, BCRC 14059, BCRC 15478, BCRC 17178 and BCRC 17638, activating the strains according to the method, performing biotransformation reaction, and analyzing the content of the fructosyl mangiferin by high performance liquid chromatography, wherein the fruits are listed in Table two. As shown in Table two, Lactobacillus plantarum BCRC 11697 has the best ability to convert into fructosyl mangiferin.

TABLE II, results of different Lactobacillus plantarum using mango peel extract as substrate, converting to fructosyl mangiferin

3. Ultraviolet absorption spectrum analysis result

FIGS. 1 and 2 are ultraviolet absorption spectra of 50 μ g/mL fructosylmangiferin standard solution and 200.0-400.0 nm of liquid product obtained by biotransformation reaction with Lactobacillus plantarum BCRC 11697, respectively. As can be seen from FIGS. 1 and 2, the fructosyl mangiferin standard substance has the same peak shape as the absorption curve of the liquid product obtained by the biotransformation reaction of Lactobacillus plantarum BCRC 11697, and has absorption peaks at the wavelengths of 238 nm, 254nm, 317 nm and 367nm, wherein the absorption peak at 254nm is strongest. Therefore, 254nm is used as the measuring wavelength of the fructosyl mangiferin standard product and the fructosyl mangiferin content of the liquid product obtained after the biotransformation reaction.

LC-MS analysis results

FIGS. 3 and 4 are LC-MS spectra of fructosyl mangiferin standard and supernatant obtained by centrifugation of bacterial cells after biotransformation reaction with Lactobacillus plantarum BCRC 11697, respectively. Comparing the LC-MS spectra in FIG. 3 and FIG. 4, it can be seen that the transformed product obtained by the biotransformation reaction of the present invention contains fructosyl mangiferin.

5. Comparing the effects of different glycosyl donors on the transformation of strains to produce fructosyl mangiferin

The results of the biotransformation reactions using Lactobacillus plantarum BCRC 11697 and different glycosyl donors (sucrose, glucose, fructose) in the previous method are shown in FIG. 5, from which it can be seen that sucrose has the highest conversion efficiency of fructosylated mangiferin, and that the fructosylated mangiferin content can reach a relatively high point of 35. mu.g/mL within 24 hours of conversion time.

6. Discussing the comparison of conversion efficiency of sucrose glycosyl to fructosyl mangiferin in different proportions

FIG. 6 is a graph comparing the effect on the conversion efficiency of fructosylated mangiferin with the addition of 0.5% to 20% (w/v) sucrose glycosyl. The control group was transformed by adding 0.5% of sugar group without adding Lactobacillus plantarum BCRC 11697 strain solution. The content of the fructosyl mangiferin is 25 mu g/mL at 0 hour. From the results of fig. 6, it can be seen that the content of fructosylation mangiferin can reach a relatively high value at 6 hours when the biotransformation reaction is carried out between the sucrose group high concentration (20%) and the sucrose group low concentration (0.5%). In addition, the group with 0.5% sucrose group has better average conversion efficiency than other high concentration groups. In figure 6, the conditions of 0.5% glycosyl and 6 hours of conversion have the highest fructosyl mangiferin content, which can reach 57 mu g/mL and is improved by more than 1 time than 25 mu g/mL of the control group.

Any numerical value mentioned in this specification, if there is only a two unit interval between any lowest value and any highest value, includes all values from the lowest value to the highest value incremented by one unit at a time. For example, if it is stated that the amount of a component, or a value of a process variable such as temperature, pressure, time, etc., is 50 to 90, it is meant in this specification that values of 51 to 89, 52 to 88 … …, and 69 to 71, and 70 to 71, etc., are specifically enumerated. For non-integer values, units of 0.1, 0.01, 0.001, or 0.0001 may be considered as appropriate. These are only some specifically named examples. In a similar manner, all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be disclosed in this application.

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.

Claims

1. A method for increasing the fructosyl mangiferin content in a plant extract comprises the following steps:

providing a plant extract containing mangiferin; and

adding a glycosyl donor into the plant extract, and carrying out biotransformation reaction in the presence of a substance with fructosyl enzyme activity to convert the mangiferin into fructosyl mangiferin, wherein the substance with fructosyl enzyme activity is generated by fermentation of Lactobacillus (Lactobacillus plantarum) with the deposition number of BCRC 11697.

2. The method of claim 1, wherein the plant extract is mango peel extract.

3. The method of claim 1, wherein the glycosyl donor is sucrose or glucose.

4. The method of claim 1, wherein the glycosyl donor is sucrose.

5. The method according to any one of claims 1 to 4, wherein the lactic acid bacterium (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

6. The method of any one of claims 1-4, wherein a fermentation broth of the lactic acid bacterium (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

7. The method of any one of claims 1-4, wherein a supernatant of a fermentation broth of lactic acid bacteria (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

8. The method of any one of claims 1 to 4, wherein fructosylase purified from a supernatant of a fermentation broth of the lactic acid bacterium (Lactobacillus plantarum) deposited under accession number BCRC 11697 is added to the plant extract.

9. The method of claim 5, wherein the bioconversion reaction is performed in a lactic acid bacteria culture medium at 20-40 ℃ and no agitation or agitation speed no greater than 400rpm for 0.5 to 96 hours, and the amount of the glycosyl donor is 1-20 g, the amount of the plant extract is 1-60mL, and the amount of the lactic acid bacteria is 10 mL, based on 100mL of the culture medium⁵～10⁷CFU/mL。

10. The method of claim 6, wherein the bioconversion reaction is performed in a lactic acid bacteria medium at 20-40 ℃ and no agitation or agitation speed no greater than 400rpm for 0.5 to 96 hours, and the amount of the glycosyl donor is 1-20 grams, the amount of the plant extract is 1-60mL, and the amount of the fermentation broth is 1-60mL, based on 100mL of the medium.

11. The method of claim 7, wherein the bioconversion reaction is performed in a lactic acid bacteria medium at 20-40 ℃ and no agitation or agitation speed no greater than 400rpm for 0.5 to 96 hours, and the amount of the glycosyl donor is 1-20 grams, the amount of the plant extract is 1-60mL, and the amount of the fermentation supernatant is 1-60mL, based on 100mL of the medium.

12. Use of lactic acid bacteria (Lactobacillus plantarum) with accession number BCRC 11697 for biotransformation reaction of mangiferin and glycosyl donor to produce fructosyl mangiferin.

13. Use of a fermentation broth of lactic acid bacteria (Lactobacillus plantarum) with accession number BCRC 11697 for biotransformation reaction of mangiferin and glycosyl donor to produce fructosyl mangiferin.

14. Use of a fermentation supernatant of lactic acid bacteria (Lactobacillus plantarum) with accession number BCRC 11697 for the bioconversion of mangiferin and a glycosyl donor to produce fructosylated mangiferin.

15. Use of a fructosylation enzyme purified from a fermentation supernatant of a lactic acid bacterium (Lactobacillus plantarum) having accession number BCRC 11697 for the bioconversion of mangiferin and a glycosyl donor to produce fructosylated mangiferin.