Method for increasing content of flavonoid aglycones in tea leaves
The fermentation of tea through Aspergillus niger RAF106 strain solved the problem of low flavonoid aglycone content in tea, significantly improved the flavonoid content and biological activity of tea, and improved its functionality.
Patent Information
- Application Number
- CN202411176105.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-26
- Publication Date
- 2025-03-11
AI Technical Summary
The prior art is difficult to efficiently convert flavonoid glycosides into tea, resulting in low flavonoid glycoside content and existing methods have problems such as high temperature, strong acid or enzyme selection.
The Aspergillus niger RAF106 strain was used to ferment the tea, and the content of flavonoid aglycones in the tea was increased by adjusting the liquid-quality ratio and fermentation conditions.
The total flavonoid content of tea has been significantly improved, and the content of flavonoid aglycone quercetin, yamphetol and saccharophenol has been increased by 488%, 524% and 125%, improving the anti-inflammatory, oxidative, anti-cancer and anti-allergic functions of tea.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of agricultural microbial fermentation, and more specifically, relates to a method for increasing the content of flavonoid aglycones in tea leaves. Background Art
[0002] Tea, as a beverage with a long history, has attracted much attention for its unique flavor and rich bioactive substances. Among them, flavonoids are important flavor and active ingredients. They are usually combined with sugar to form glycosides (i.e., flavonoid glycosides) and exist in a small amount of free state (i.e., flavonoid aglycones). Flavonoid glycosides have good water solubility, but the presence of sugar groups will affect the interaction between the active site of flavonoids and the target, thereby reducing their bioavailability and biological activity. Flavonoid aglycones do not contain sugar groups, have enhanced fat solubility, and are more likely to penetrate the cell membrane into the body, so they often show stronger biological activities, such as antioxidant, anti-inflammatory, antibacterial, and anti-tumor.
[0003] Existing studies usually use acid (base) hydrolysis, enzyme catalysis and biotransformation to hydrolyze or deglycosylate flavonoid glycosides to convert them into flavonoid aglycones. Although the acid hydrolysis method can achieve the hydrolysis of flavonoid glycosides, this method usually requires high temperature and strong acid or strong base as a catalyst, which makes the reaction conditions more stringent and easily causes insufficient thermal stability of the reactants, resulting in incomplete reactions or side reactions. The enzyme catalysis method is extremely important for the selection of enzymes, and its conversion method is cumbersome, and there is also a problem of low conversion rate. For example, in the existing research, after the sea buckthorn flavonoid glycosides were pretreated with a composite enzyme composed of α-rhamnosidase, β-glucosidase, xylanase, cellulase, pectinase and α-amylase, the conversion rate of flavonoid glycosides was only 0.23%, and then hydrolysis with naringinase can obtain a high content of flavonoid aglycones. The biotransformation method uses microorganisms and the enzymes they produce for conversion, which is a green, sustainable and efficient method. Among them, Aspergillus niger is one of the main bacterial species used for microbial transformation of chemical components. Compared with other known bacterial species, Aspergillus niger is a lower eukaryotic organism recognized by the world as safe for consumption and widely used in the food industry. Aspergillus niger can be used to transform daidzein and genistin in soybeans, or to transform flavonoid aglycones in tangerine peel and sea buckthorn. For example, Cheng Yongqiang et al. used Aspergillus niger to ferment sea buckthorn leaves at 28-42°C for 2-10 days, so that the conversion rate of quercetin, kaempferol and isorhamnetin reached 14-23%, but this method still has the problem of low conversion efficiency.
[0004] In summary, there is currently a lack of methods for efficiently converting flavonoid glycosides in tea and increasing the content of flavonoid aglycones in tea. Summary of the invention
[0005] The purpose of the present invention is to solve the problem of low flavonoid aglycone content in tea leaves and the insufficiency of existing conversion technology, and to provide a method for increasing the flavonoid aglycone content in tea leaves.
[0006] Another object of the present invention is to provide the use of Aspergillus niger RAF106 strain in increasing the content of flavonoid aglycones and flavonoids in tea leaves.
[0007] The above-mentioned purpose of the present invention is achieved through the following technical solutions:
[0008] The invention provides a method for improving the content of flavonoid aglycones in tea leaves. Sterile water is added to tea leaves until the water content of the tea leaves is 20-50%, Aspergillus niger is uniformly inoculated on the tea leaves at a liquid-to-mass ratio of 1:90-110 mL / g, and the tea leaves are mixed and fermented. The fermentation conditions are 25-45 DEG C and 2-8 days, and the tea leaves are dried after the fermentation is completed. The Aspergillus niger adopts Aspergillus niger RAF106 strain, the preservation number of the strain is CGMCCNO.9608, and the preservation date is August 27, 2014.
[0009] The method provided by the present invention can significantly increase the total flavonoid content of tea, which is increased by 15-55% compared with that before fermentation, and the content of flavonoid aglycones quercetin, kaempferol and eriodictyol is increased by 488%, 524% and 125% respectively compared with that before fermentation after fermentation by Aspergillus niger, which is further used to enhance the anti-inflammatory, oxidative, anti-cancer and anti-allergic functions thereof, and provides more effective methods for increasing the content of effective substances in tea, which is of great significance to the development and promotion and application of tea.
[0010] Preferably, the tea leaves are not limited to fresh tea or fermented tea, and specifically Yunnan large-leaf tea is used.
[0011] Preferably, the Aspergillus niger is an Aspergillus niger spore suspension.
[0012] Preferably, the preparation method of the Aspergillus niger spore suspension is: inoculate Aspergillus niger on a culture medium, culture at 28-40° C. for 5-7 days, wait until the surface of the culture medium is covered with spores, rinse the spores with sterile water, collect the rinse liquid, and oscillate evenly to obtain the Aspergillus niger spore suspension.
[0013] Preferably, the concentration of the Aspergillus niger spore suspension is not less than 1-2×10 8 Pieces / mL.
[0014] Preferably, the method can increase the total flavonoids content of tea leaves.
[0015] Preferably, the method can increase the content of quercetin, kaempferol and / or eriodictyol in tea leaves.
[0016] Preferably, the tea leaves are turned every day during the fermentation period.
[0017] The present invention provides a more preferred method, specifically:
[0018] The tea leaves are rehydrated with sterile water to a water content of 25-45%, and the Aspergillus niger spore suspension is evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1 mL: 90-100 g. After the tea leaves are evenly mixed, they are fermented and cultured at 35-45° C. During the fermentation period, the tea leaves are turned over every day. After fermentation for 2-6 days, the tea leaves are placed in an oven at 80° C. for drying to obtain tea leaves with a high flavonoid content, which are then vacuum packaged and stored. The invention also provides an application of the Aspergillus niger RAF106 strain in improving the flavonoid content in tea leaves.
[0019] The invention provides application of Aspergillus niger RAF106 strain in improving the content of flavonoid aglycones in tea leaves.
[0020] The invention provides application of Aspergillus niger RAF106 strain in improving the total flavonoid content of tea leaves.
[0021] Preferably, the RAF106 strain can increase the total flavonoid content of tea leaves.
[0022] Preferably, the RAF106 strain can increase the content of quercetin, kaempferol and / or eriodictyol in tea leaves.
[0023] The present invention has the following beneficial effects:
[0024] The invention provides a method for increasing the content of flavonoid aglycones in tea leaves. The Aspergillus niger RAF106 strain is used to ferment tea leaves, so that the total flavonoid content in the tea leaves can be increased by 15-55% compared with that before fermentation. The flavonoid substances are converted from macromolecular substances into small molecular substances through the fermentation of Aspergillus niger, and the contents of the flavonoid aglycones quercetin, kaempferol and eriodictyol are significantly increased, the conversion rate is improved, and the anti-inflammatory, oxidative, anti-cancer and anti-allergic functions thereof are further improved, so that more effective methods are provided for increasing the content of effective substances in tea leaves, and the method is of great significance to the development, promotion and application of tea leaves. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 The overall profile of flavonoids in GT and FT (a: Venn diagram; b: heat map).
[0026] Figure 2 Differential metabolite analysis of flavonoids in GT and FT (a: OPLS-DA score plot; b: model cross-validation plot; c: volcano plot; d: violin plot).
[0027] Figure 3 Schematic diagram of the main differential metabolite structures of GT and FT. DETAILED DESCRIPTION
[0028] The present invention is further described below in conjunction with the accompanying drawings and specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.
[0029] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.
[0030] The Aspergillus niger RAF106 strain used in this embodiment is the preliminary research result of the applicant's research team. The deposit date of the RAF106 strain is August 27, 2014, and the deposit number is CGMCCNO.9608. The depositor is the General Microbiology Center of China Microbiological Culture Collection Administration (CGMCC); the depositor's address is No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, China, and is recorded in the existing patent document: CN 10467384 A.
[0031] Example 1 Preparation of fermented tea
[0032] (1) Preparation of Aspergillus niger spore suspension
[0033] Take the Aspergillus niger glycerol tube stored at -20℃, use an inoculation needle to inoculate it on the PDA plate, and culture it at 28-40℃ for 5-7 days. When the surface of the culture medium is full of spores, wash the spores with 0.1% Tween 80 sterile water, transfer them to a 10mL centrifuge tube, and oscillate evenly to form an Aspergillus niger spore suspension. Then use a hemocytometer to adjust the concentration of the spore suspension to 1-2×10 8 The spore suspension was stored at -20℃.
[0034] (2) Preparation of fermented tea
[0035] 100g of tea leaves (Yunnan large-leaf variety) were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 2 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0036] Example 2 Preparation of fermented tea
[0037] 100g of tea leaves (Yunnan large-leaf variety) were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 4 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0038] Example 3 Preparation of fermented tea
[0039] 100g of tea leaves (Yunnan large-leaf variety) were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 6 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0040] Example 4 Preparation of fermented tea
[0041] 100g of tea leaves were weighed and rehydrated with sterile water to a water content of 20%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 4 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0042] Example 5 Preparation of fermented tea
[0043] 100g of tea leaves were weighed and rehydrated with sterile water to a water content of 50%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 4 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0044] Example 6 Preparation of fermented tea
[0045] 100g of tea leaves were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:90g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 4 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0046] Example 7 Preparation of fermented tea
[0047] 100g of tea leaves were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:110g. After the tea leaves were evenly mixed, they were placed in a 42°C fermentation incubator for fermentation. During the fermentation period, the tea leaves were turned over every day, and the tea leaves fermented for 6 days were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0048] Example 8 Preparation of fermented tea
[0049] 100g of tea leaves were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 25°C fermentation incubator for fermentation. The fermentation lasted for 4 days, during which the tea leaves were turned over every day. The fermented tea leaves were placed in an 80°C oven for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0050] Example 9 Preparation of fermented tea
[0051] 100g of tea leaves were weighed and rehydrated with sterile water to a water content of 40%, and the Aspergillus niger spore suspension was evenly inoculated on the tea leaves at a liquid-to-mass ratio of 1mL:100g. After the tea leaves were evenly mixed, they were placed in a 45°C fermentation incubator for fermentation. The fermentation lasted for 6 days, during which the tea leaves were turned over every day. The fermented tea leaves were placed in an oven at 80°C for drying and vacuum-packed for storage to obtain lightly fermented tea.
[0052] Example 10 Determination of total flavonoid content in fermented tea
[0053] 1. Experimental methods:
[0054] (1) Test solution preparation: Weigh 1 mg of rutin standard into a 1.5 mL centrifuge tube and dissolve it in 1 mL of methanol to prepare a 1 mg / mL rutin standard solution. Pipette 100 μL of rutin standard solution into a 1.5 mL centrifuge tube containing 900 μL of 60% anhydrous ethanol to prepare a 100 μg / mL standard test solution. Prepare 80, 40, 20, 10, and 5 μg / mL standard test solutions in sequence.
[0055] (2) Preparation of sample extract: Weigh 0.10 g of the fermented tea prepared in Examples 1-3 and ground tea samples into a 10 mL centrifuge tube, add 5 mL of 60% ethanol, perform ultrasonic-assisted extraction for 30 min, centrifuge at 8000 rpm for 5 min, take the supernatant, repeat the extraction once, and combine the supernatants in a 10 mL volumetric flask to make up to volume.
[0056] (3) Determination: Pipette 100 μL of standard test solution and sample solution into 1.5 mL centrifuge tubes, add 150 μL of 5% AlCl3 solution, then add 100 μL of acetic acid-sodium acetate buffer (pH=5.5), dilute to 1.0 mL with 60% ethanol, let stand for 30 min, measure the absorbance of the extract at 400 nm, and use 60% ethanol test solution as a blank control. According to the absorbance of each standard test solution, establish a flavonoid concentration-absorbance value standard curve, obtain the concentration of the sample flavonoid compound according to the standard curve, and calculate the percentage of the flavonoid compound in the tea sample. The calculation formula is as follows:
[0057]
[0058] Where: X—total flavonoids content in tea leaves (mg / g);
[0059] x1—calculate the total flavonoids concentration (μg / mL) in the test solution according to the standard curve;
[0060] n—dilution multiple of the assay solution;
[0061] V—volume of tea extract (mL);
[0062] M—Weigh the mass of tea sample (g).
[0063] 2. Experimental results:
[0064] The results of the changes in the total flavonoid content during the fermentation process are shown in Table 1. The total flavonoid content first increased and then decreased with the increase of time during the fermentation process. After 4 days of fermentation, the total flavonoid content of tea reached its maximum value, an increase of 54.65% compared with before fermentation (p<0.05). After 6 days of fermentation, the total flavonoid content decreased to 0.84%, which was not significantly different from before fermentation (p>0.05). It can be seen that short-term fermentation with RAF106 strain is conducive to the accumulation of tea flavonoids, and the flavonoid content reached the highest level after 4 days of fermentation.
[0065] Table 1 Flavonoid content at different fermentation times
[0066]
[0067] Example 11 Determination of flavonoid compounds in fermented tea
[0068] 1. Experimental methods:
[0069] (1) Samples: The fermented tea (FT) fermented for 4 days in Example 2 and the unfermented tea (GT) were used for metabolite analysis.
[0070] (2) Sample pretreatment: Grind the tea sample into powder using a ball mill (30 Hz, 1.5 min), weigh 20 mg of the powder into a 1.5 mL centrifuge tube, add 10 μL of 4000 nmol / L internal standard mixed working solution ([2H6] daidzein, [2H3] rutin, [13C3]-(+ / -)-gallocatechin gallate) and 500 μL of 70% methanol solution, sonicate for 30 min, and centrifuge at 4°C (speed 12.000 r / min, 5 min), aspirate the supernatant, filter the sample with a 0.22 μm filter membrane, and store it in an injection bottle for liquid chromatography tandem mass spectrometry (LC-MS / MS) analysis.
[0071] (3) Chromatography-mass spectrometry acquisition conditions: The data acquisition instrument system mainly includes ultra-high performance liquid chromatography and tandem mass spectrometry ( 6500+).
[0072] (4) Liquid phase conditions mainly include: chromatographic column: Waters ACQUITY UPLC HSS T3 C18 column (1.8um, 100mmx2.1mm id); mobile phase: phase A is ultrapure water (containing 0.05% formic acid), phase B is acetonitrile (containing 0.05% formic acid); flow rate is 0.35mL / min; column temperature is 40℃; injection volume is 2μ; elution gradient: 0minA / B is 90:10 (V / V), 1minA / B is 80:20 (V / V), 9min is 30:70 (V / V), 12.5min A / B is 5:95 (V / V), 13.5min is 5:95 (V / V), 13.6min is 90:10 (V / V), 15min is 90:10 (V / V).
[0073] (5) The mass spectrometry conditions mainly include: electrospray ion source temperature 550°C, mass spectrometry voltage 5500 V in positive ion mode, mass spectrometry voltage -4500 V in negative ion mode, and drying gas 35 psi. In Q-Trap 6500+, each ion pair is scanned and detected based on the optimized declustering voltage and collision energy.
[0074] (6) Qualitative and quantitative principles: Based on the standard samples, the MWDB (Metware Database) database is constructed to perform qualitative analysis on the mass spectrometry data. Quantitative analysis is performed using the multiple reaction monitoring mode of triple quadrupole mass spectrometry and the standard curve.
[0075] 2. Experimental results:
[0076] LC-MS / MS was used to quantitatively analyze the flavonoid content in GT and FT. Figure 1 As shown in the figure, there are 68 flavonoids detected, of which 38 are common to GT and FT, 16 are unique to GT, and 14 are unique to FT, indicating that there are differences in the types of flavonoids between GT and FT ( Figure 1 a). In addition, the results of the clustering diagram also showed that the concentration of flavonoids between GT and FT was quite different ( Figure 1 b).
[0077] At the same time, an OPLS-DA model was constructed to analyze the difference in flavonoids between GT and FT. The results are as follows Figure 2 As shown, the statistical parameter of the model is R 2 Y=0.999 and Q 2 =0.994. The closer the parameter values are to 1, the better the applicability and predictability of the model. Figure 2 ab), and further screening of differential metabolites can be performed.
[0078] After OPLS-DA analysis, substances with VIP values greater than 1 were screened out, and their change trends were further determined by combining the FC values. Finally, according to the conditions of VIP>1, p<0.05, |Log2FC|>1, 41 differential metabolites between GT and FT were obtained ( Figure 2 cd), compared with GT, FT had 20 substances with increased content and 21 substances with decreased content. Among these differential metabolites, GT was dominated by rutin, quercetin and arginine, which accounted for 82.35% of the total differential metabolites. FT was dominated by quercetin, kaempferol and eriodictyol, which accounted for 95.93% of the total differential metabolites. The contents of some flavonoids in the samples were determined as shown in Table 2.
[0079] Table 2 Summary of the contents of some flavonoids in samples
[0080]
[0081]
[0082] As can be seen from Table 2, after fermentation, flavonoids are transformed from macromolecular substances to small molecular substances. Among them, macromolecular substances rutin and arginine were not detected in FT, and the content of small molecular substances quercetin, kaempferol, and eriodictyol was increased. The schematic diagram of the differential metabolite structure is shown in Figure 3 As shown, quercetin, kaempferol, and eriodictyol in FT increased by 488%, 524%, and 125%, respectively, compared with GT.
[0083] In summary, the present invention provides a method for increasing the content of flavonoid aglycones in tea leaves, wherein the Aspergillus niger RAF106 strain is used to ferment tea leaves, and during the fermentation process, Aspergillus niger releases extracellular enzymes such as cellulase, pectinase, etc. The produced enzymes can catalyze the conversion of flavonoid precursors in tea leaves into flavonoids or their derivatives, destroy the cell wall structure, and make the flavonoid compounds in the cells easier to dissolve and extract; after fermentation by Aspergillus niger, not only can the total flavonoid content of tea leaves be increased by 15-55% compared with that before fermentation, but also the content of flavonoid aglycones is increased, and flavonoid substances are converted from macromolecular substances into small molecular substances, and the content of flavonoid aglycones quercetin, kaempferol, and eriodictyol is increased, and its anti-inflammatory, oxidative, anti-cancer and anti-allergic functions can be further improved. The present invention provides more effective methods for increasing the content of effective substances in tea leaves, which is of great significance to the development and promotion of tea leaves.
[0084] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.
Claims
1. A method for increasing the content of flavonoid aglycones in tea, characterized in that: Take tea leaves and add sterile water to a water content of 20-50%, evenly inoculate Aspergillus niger on the tea leaves at a liquid-to-mass ratio of 1:90-110 mL / g, mix well and ferment, the fermentation conditions are 25-45° C., 2-8 days, and dry after the fermentation is completed; The Aspergillus niger adopts Aspergillus niger RAF106 strain, the preservation number of the strain is CGMCCNO.9608, and the preservation date is August 27, 2014.
2. The method according to claim 1, characterized in that: The Aspergillus niger is an Aspergillus niger spore suspension.
3. The method according to claim 2, characterized in that: The preparation method of the Aspergillus niger spore suspension is as follows: inoculate Aspergillus niger on a culture medium, culture at 28-40° C. for 5-7 days, wait until the surface of the culture medium is covered with spores, rinse the spores with sterile water, collect the rinse liquid, and oscillate evenly to obtain the Aspergillus niger spore suspension.
4. The method according to claim 3, characterized in that: The concentration of the Aspergillus niger spore suspension is not less than 1-2×10 8 Pieces / mL.
5. The method according to claim 1, characterized in that: The method can increase the total flavonoid content of tea leaves.
6. The method according to claim 1, characterized in that: The method can increase the content of flavonoid aglycones in tea leaves.
7. The method according to claim 1, characterized in that: The tea leaves are turned every day during the fermentation period.
8. Application of Aspergillus niger RAF106 strain in increasing the content of flavonoid aglycones in tea, characterized in that: The deposit number of this strain is CGMCCNO.9608, and the deposit date is August 27, 2014.
9. Application of Aspergillus niger RAF106 strain in increasing the total flavonoid content of tea, characterized in that: The deposit number of this strain is CGMCCNO.9608, and the deposit date is August 27, 2014.
10. The use according to claim 8 or 9, characterized in that: The RAF106 strain can increase the content of quercetin, kaempferol and / or eriodictyol in tea leaves.