A process for efficiently extracting anthocyanins from lycium ruthenicum murr.
By using a compound enzyme system and a gradient fermentation strategy, the problem of low extraction rates of anthocyanins and total alkaloids in black goji berries was solved, and the content of anthocyanins and total alkaloids in the extract was increased simultaneously, meeting the high added value requirements of industrial production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING GUOHUA XINYE TRADITIONAL CHINESE MEDICINE RES INST CO LTD
- Filing Date
- 2026-02-27
- Publication Date
- 2026-06-09
AI Technical Summary
Existing technologies have failed to design a specific anthocyanin extraction scheme for black goji berries, and cannot simultaneously increase the content of total alkaloids and anthocyanins in the extract, making it difficult to meet the high added value requirements of industrial production.
A complex enzyme system (cellulase, pectinase, and β-glucosidase) was used to synergistically break down cell walls. Combined with a gradient fermentation strategy of first aerobic and then anaerobic fermentation, a complex strain of Aspergillus niger, Lactobacillus rhamnosus, and Lactobacillus paracasei was used to simultaneously extract anthocyanins and total alkaloids through enzymatic hydrolysis and fermentation.
It significantly increased the content of anthocyanins and total alkaloids in black goji berry extract, thereby enhancing the overall physiological activity of the extract and meeting the high added value requirements of industrial production.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of plant active ingredient extraction technology, specifically relating to a process for efficiently extracting anthocyanins from black goji berries. Background Technology
[0002] Black goji berries (Lycium ruthenicum). Black goji berries are rich in active ingredients, mainly including anthocyanins and total alkaloids, both of which have excellent physiological activities and broad application prospects in functional foods, natural pigments, and pharmaceuticals.
[0003] Currently, there are relevant reports on the extraction of active ingredients from black goji berries. CN 113855657 B discloses the preparation method of anthocyanin extract and freeze-dried powder from black goji berries. Specifically, it is prepared through several steps including extraction, high-speed centrifugation and ceramic membrane filtration, organic membrane degumming and concentration, simulated moving bed chromatography separation, low-temperature concentration, freeze drying and freeze-dried powder preparation.
[0004] While existing technologies have attempted to improve the anthocyanin extraction rate from various plants using enzymatic hydrolysis or fermentation, none of these technologies have designed a specific anthocyanin extraction scheme for black goji berries. They fail to adequately adapt to the cell wall structure and the state of active substances in black goji berries, resulting in limited extraction effects. Furthermore, they do not consider the stability of anthocyanin and total alkaloid components, making it difficult to achieve ideal levels of anthocyanin and total alkaloid content in the extracted black goji berry extract. This hinders the simultaneous improvement of the extraction rate of total alkaloids and anthocyanins in black goji berry extract, making it difficult to meet the needs of preparing high-value-added black goji berry extracts in industrial production and limiting the in-depth development and comprehensive utilization of black goji berry resources.
[0005] Therefore, there is an urgent need for a process to efficiently extract anthocyanins from black goji berries. Summary of the Invention
[0006] The purpose of this invention is to provide a process for efficiently extracting anthocyanins from black goji berries, which can simultaneously improve the extraction rates of total alkaloids and anthocyanins in black goji berry extracts.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] A process for efficiently extracting anthocyanins from black goji berries includes the following steps: Step 1: Crush the dried black goji berries to obtain black goji berry powder; Step 2: Add buffer solution to black goji berry powder to obtain black goji berry suspension; add compound enzyme to black goji berry suspension for enzymatic hydrolysis, inactivate enzyme, cool to obtain enzymatic hydrolysate; Step 3: Add Aspergillus niger to the enzymatic hydrolysate, ferment, sterilize, and obtain the primary fermentation broth; continue to add compound bacteria, carry out anaerobic fermentation, sterilize, cool, and obtain the final fermentation broth; Step 4: Extract the final fermentation broth with alcohol to remove the ethanol and obtain a concentrated crude extract; Step 5: Purify the concentrated crude extract using AB-8 macroporous adsorption resin, and dry it to obtain black goji berry extract.
[0009] Preferably, the complex enzyme includes cellulase, pectinase and β-glucosidase.
[0010] Preferably, the mass ratio of cellulase: pectinase: β-glucosidase is 1:(0.5-0.6):(0.2-0.3).
[0011] Preferably, the enzymatic hydrolysis conditions are: a hydrolysis temperature of 40-45℃ and a hydrolysis time of 70-90 min.
[0012] Existing technologies often employ single cellulase or pectinase for cell wall disruption, which only damages the plant cell wall structure and fails to fully release bound alkaloids, resulting in a low total alkaloid extraction rate from black goji berries. This invention utilizes a composite enzyme system composed of cellulase, pectinase, and β-glucosidase in a specific mass ratio. Through the synergistic action of these three enzymes, it not only efficiently breaks down the cell wall skeleton but also specifically cleaves the covalent bonds between alkaloids and glycosyl groups, converting bound alkaloids into free alkaloids and significantly increasing the total alkaloid content in black goji berry extract.
[0013] Preferably, the amount of compound enzyme used is 2.0-2.2% of the mass of black goji berry powder.
[0014] Preferably, the inoculum size of Aspergillus niger is (1-3) × 10⁻⁶. 8 CFU / mL enzyme hydrolysate.
[0015] The preferred fermentation conditions for Aspergillus niger are: fermentation temperature of 30-35℃, stirring speed of 200-250 r / min, aeration rate of 0.8-1.0 vvm, and fermentation time of 60-80 h.
[0016] Preferably, the compound bacteria include Lactobacillus rhamnosus and Lactobacillus paracasei.
[0017] Preferably, the live count ratio of Lactobacillus rhamnosus to Lactobacillus paracasei is 1:(0.3-0.5), and the inoculum size of the compound bacteria is (1-3)×10⁻⁶. 8 CFU / mL primary fermentation broth
[0018] Existing technologies typically employ single-strain or simple mixed-strain fermentation, which struggles to accommodate the diverse metabolic characteristics and fermentation conditions required by different microorganisms, thus limiting the release efficiency of anthocyanins and alkaloids from black goji berries. This invention utilizes a gradient fermentation strategy, first aerobic and then anaerobic. In the initial stage, *Aspergillus niger* is used for fermentation under optimized conditions to effectively break down residual cell wall structures and release bound anthocyanins and alkaloids. In the subsequent stage, a complex of *Lactobacillus rhamnosus* and *Lactobacillus paracasei* is introduced for further modification and transformation through anaerobic fermentation, promoting the full dissolution and active conversion of alkaloids. Through the synergistic effect of these two fermentation steps, a significant increase in anthocyanin yield is achieved, while simultaneously and substantially improving the extraction rate and conversion efficiency of total alkaloids. Ultimately, this results in a simultaneous increase in the total alkaloid and anthocyanin content of the black goji berry extract, significantly enhancing the overall physiological activity of the extract.
[0019] The preferred anaerobic fermentation conditions are: fermentation temperature 35-37℃, fermentation time 20-40h, and stirring speed 100-150r / min.
[0020] The anthocyanin content in black goji berry extract is 91.47-91.81 wt%, and the total alkaloid content is 1.03-1.12 wt%.
[0021] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: 1. This invention uses a complex enzyme system composed of cellulase, pectinase and β-glucosidase in a specific mass ratio. Through the synergistic effect of the three enzymes, it can not only efficiently break the cell wall skeleton, but also specifically cleave the covalent bonds between alkaloids and sugar groups, converting bound alkaloids into free alkaloids, and significantly increasing the total alkaloid content in black goji berry extract.
[0022] 2. This invention employs a gradient fermentation strategy of first aerobic and then anaerobic fermentation. In the early stage, Aspergillus niger is used for fermentation under optimized conditions to effectively break down the residual cell wall structure and release bound anthocyanins and alkaloids. In the later stage, a complex of Lactobacillus rhamnosus and Lactobacillus paracasei is introduced to further modify and transform the bacteria through anaerobic fermentation, thereby promoting the full dissolution and active transformation of alkaloids.
[0023] 3. This invention achieves a significant increase in anthocyanin yield through the synergistic effect of two-step fermentation, while also greatly improving the extraction rate and conversion efficiency of total alkaloids. Ultimately, it achieves a simultaneous increase in the total alkaloid and anthocyanin content in black goji berry extract, significantly enhancing the comprehensive physiological activity of the extract. Detailed Implementation
[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] The raw materials and strains used in the following embodiments of the present invention are all commercially available products: Cellulase, product number S10041, Shanghai Yuanye Biotechnology Co., Ltd.
[0026] Pectinase, product number S10007, Shanghai Yuanye Biotechnology Co., Ltd.
[0027] β-glucosidase, product number S24786, Shanghai Yuanye Biotechnology Co., Ltd.
[0028] Aspergillus niger, strain number: CICC 2300, China Industrial Microbial Culture Collection Center.
[0029] Lactobacillus rhamnosus, strain number: CICC 6137, China Industrial Microbial Culture Collection Center.
[0030] Polymyxin Bacillus, CICC 20185, China Industrial Microbial Culture Collection Center.
[0031] Lactobacillus paracasei, strain number: HZB195035, Zhengzhou Fangjue Biotechnology Co., Ltd.
[0032] Example 1 This embodiment provides a process for efficiently extracting anthocyanins from black goji berries, including the following steps: Step 1: Pre-treatment of black goji berry raw materials: Grind the dried black goji berries into powder smaller than 60 mesh to obtain black goji berry powder; Step 2: Enzymatic hydrolysis: Place 100g of black goji berry powder obtained in Step 1 into an Erlenmeyer flask, add 1500mL of PBS buffer (pH=5.5) at a liquid-to-solid ratio of 15:1 (mL / g), and stir until homogeneous to obtain a black goji berry suspension; add a complex enzyme, including cellulase, pectinase, and β-glucosidase, to the black goji berry suspension, with a cellulase:pectinase:β-glucosidase mass ratio of 1:0.5:0.3, and the amount of complex enzyme is 2.2% of the mass of the black goji berry powder, and stir until the enzyme is completely dissolved; place in a constant temperature water bath for enzymatic hydrolysis, setting the hydrolysis temperature to 45℃ and the hydrolysis time to 80min; after the hydrolysis is completed, heat in a 90℃ water bath for 10min to inactivate the enzyme, and cool to room temperature to obtain the enzymatic hydrolysate; Step 3: Fermentation treatment: Transfer the enzymatic hydrolysate obtained in Step 2 into a sterile fermenter, adjust the pH of the system to 5.5, and add Aspergillus niger at a dosage of 10 g / L. 8 The enzyme hydrolysate was prepared at a concentration of CFU / mL. The fermentation temperature was set at 30℃, the stirring speed at 200 rpm, the aeration rate at 0.8 vvm, and the fermentation time at 70 h. The mixture was then heated in an 80℃ water bath for 30 min to obtain the primary fermentation broth. The pH of the primary fermentation broth was adjusted to 6.0, and a compound culture was added. The compound culture consisted of *Lactobacillus rhamnosus* and *Lactobacillus paracasei*, with a viable count ratio of 1:0.4. The total amount of the compound culture was 10... 8 CFU / mL of primary fermentation broth was stirred evenly; fermentation culture was carried out: the fermentation temperature was set at 37℃, the fermentation time at 30h, the stirring speed at 100r / min, and anaerobic fermentation was performed; after fermentation was completed, the fermentation broth was placed in an 80℃ water bath for 15min to inactivate the bacterial strain and metabolic enzymes, and then cooled to room temperature to obtain the final fermentation broth. Step 4: Preliminary extraction and solid-liquid separation: Add anhydrous ethanol to the final fermentation broth obtained in Step 3, adjust the ethanol volume fraction to 49%, stir evenly, and extract at room temperature for 30 min, stirring twice for 5 min each time; after extraction, transfer the mixture to a high-speed centrifuge, centrifuge at 8000 r / min and 4℃ for 20 min, collect the supernatant to obtain the crude anthocyanin extract; place the crude extract in a rotary evaporator, concentrate at 45℃ and 0.08 MPa vacuum to remove ethanol, and obtain the concentrated crude extract; Step 5: Purification: Take 50g of AB-8 macroporous adsorption resin and soak it in 95% (v / v) ethanol aqueous solution for 24h to remove impurities from the resin; rinse the resin with deionized water until there is no ethanol odor, then soak it in 5wt% hydrochloric acid for 2h, and rinse it with deionized water until neutral; finally, soak it in 5wt% sodium hydroxide aqueous solution for 2h, and rinse it with deionized water until neutral to obtain pretreated AB-8 macroporous adsorption resin; load the concentrated crude extract obtained in Step 4 into the pretreated AB-8 macroporous adsorption resin at a flow rate of 2BV / h (BV is the resin column volume), and after loading, let it stand for 2h for adsorption; first use deionized water... The resin was rinsed with water at a flow rate of 3 BV / h until the eluent was colorless and transparent; then eluted with 10 (v / v)% ethanol aqueous solution at a flow rate of 2.5 BV / h, and the eluent was collected, with an eluent volume of 5 BV; the resin column was eluted with 60 (v / v)% ethanol aqueous solution at a flow rate of 2 BV / h, and the eluent was collected, with an eluent volume of 4 BV. The eluents were combined to obtain a purified eluent; the purified eluent was placed in a rotary evaporator and concentrated at 45°C until no ethanol odor was detected, to obtain a concentrated solution; the concentrated solution was placed in a vacuum freeze dryer and freeze-dried at -50°C and a vacuum degree of 0.01 MPa to constant weight to obtain black goji berry extract.
[0033] Example 2 This embodiment provides a process for efficiently extracting anthocyanins from black goji berries, including the following steps: Step 1: Pre-treatment of black goji berry raw materials: Grind the dried black goji berries into powder smaller than 60 mesh to obtain black goji berry powder; Step 2: Enzymatic hydrolysis: Place 100g of black goji berry powder obtained in Step 1 into an Erlenmeyer flask, add 1500mL of PBS buffer (pH=5.5) at a liquid-to-solid ratio of 15:1 (mL / g), and stir until homogeneous to obtain a black goji berry suspension; add a compound enzyme to the black goji berry suspension, the compound enzyme consisting of cellulase:pectinase:β-glucosidase = 1:0.6:0.2, the amount of compound enzyme being 2.2% of the mass of black goji berry powder, and stir until the enzyme is completely dissolved; place in a constant temperature water bath for enzymatic hydrolysis, setting the hydrolysis temperature to 45℃ and the hydrolysis time to 90min; after the hydrolysis is completed, heat in a 90℃ water bath for 10min to inactivate the enzyme, and cool to room temperature to obtain the enzymatic hydrolysate; Step 3: Fermentation treatment: Transfer the enzymatic hydrolysate obtained in Step 2 into a sterile fermenter, adjust the pH of the system to 5.5, and add Aspergillus niger. The inoculum size of Aspergillus niger is 10. 8 The enzyme hydrolysate was prepared at a concentration of CFU / mL. The fermentation temperature was set at 30℃, stirring speed at 200 rpm, aeration rate at 0.8 vvm, and fermentation time at 60 h. The mixture was then heated in an 80℃ water bath for 30 min to obtain the primary fermentation broth. The pH of the primary fermentation broth was adjusted to 6.0, and a compound culture was added. The compound culture consisted of *Lactobacillus rhamnosus* and *Lactobacillus paracasei*, with a viable count ratio of 1:0.5. The inoculum size was 10 μL. 8 CFU / mL of primary fermentation broth was stirred evenly; fermentation culture was carried out: the fermentation temperature was set at 37℃, the fermentation time at 36h, the stirring speed at 100r / min, and anaerobic fermentation was performed; after fermentation was completed, the fermentation broth was placed in an 80℃ water bath for 15min to inactivate the bacterial strain and metabolic enzymes, and then cooled to room temperature to obtain the final fermentation broth. Step 4: Preliminary extraction and solid-liquid separation: Add anhydrous ethanol to the final fermentation broth obtained in Step 3, adjust the ethanol volume fraction to 49%, stir evenly, and extract at room temperature for 30 min, stirring twice for 5 min each time; after extraction, transfer the mixture to a high-speed centrifuge, centrifuge at 8000 r / min and 4℃ for 20 min, collect the supernatant to obtain the crude anthocyanin extract; place the crude extract in a rotary evaporator, concentrate at 45℃ and 0.08 MPa vacuum to remove ethanol, and obtain the concentrated crude extract; Step 5: Purification: Take 50g of AB-8 macroporous adsorption resin and soak it in 95% (v / v) ethanol aqueous solution for 24h to remove impurities from the resin; rinse the resin with deionized water until there is no ethanol odor, then soak it in 5wt% hydrochloric acid for 2h, and rinse it with deionized water until neutral; finally, soak it in 5wt% sodium hydroxide aqueous solution for 2h, and rinse it with deionized water until neutral to obtain pretreated AB-8 macroporous adsorption resin; load the concentrated crude extract obtained in Step 4 into the pretreated AB-8 macroporous adsorption resin at a flow rate of 2BV / h (BV is the resin column volume), and after loading, let it stand for 2h for adsorption; first use deionized water... The resin was rinsed with water at a flow rate of 3 BV / h until the eluent was colorless and transparent; then eluted with 10 (v / v)% ethanol aqueous solution at a flow rate of 2.5 BV / h, and the eluent was collected, with an eluent volume of 5 BV; the resin column was eluted with 60 (v / v)% ethanol aqueous solution at a flow rate of 2 BV / h, and the eluent was collected, with an eluent volume of 4 BV. The eluents were combined to obtain a purified eluent; the purified eluent was placed in a rotary evaporator and concentrated at 45°C until no ethanol odor was detected, to obtain a concentrated solution; the concentrated solution was placed in a vacuum freeze dryer and freeze-dried at -50°C and a vacuum degree of 0.01 MPa to constant weight to obtain black goji berry extract.
[0034] Comparative Example 1 The difference between this comparative example and Example 1 is that the complex enzyme includes cellulase and pectinase; the mass ratio of cellulase to pectinase is 1:0.5.
[0035] Comparative Example 2 The difference between this comparative example and Example 1 is that the complex enzyme includes cellulase, pectinase, and β-glucosidase. The mass ratio of cellulase:pectinase:β-glucosidase is 1:0.4:0.4.
[0036] Comparative Example 3 The difference between this comparative example and Example 1 is that the complex enzyme includes cellulase, pectinase, and β-glucosidase. The mass ratio of cellulase:pectinase:β-glucosidase is 1:0.7:0.1.
[0037] Comparative Example 4 The difference between this comparative example and Example 1 is as follows: Step 3: Fermentation treatment: The enzymatic hydrolysate obtained in Step 2 is transferred to a sterile fermenter, the pH is adjusted to 6.0 with sterile alkali solution, and a compound bacteria is added. The compound bacteria include Lactobacillus rhamnosus and Lactobacillus paracasei, with a live bacteria ratio of Lactobacillus rhamnosus to Lactobacillus paracasei of 1:0.4, and the inoculum size of the compound bacteria is 10. 8CFU / mL enzyme hydrolysate was stirred evenly; fermentation culture was carried out: the fermentation temperature was set at 37℃, the fermentation time at 30h, the stirring speed at 100r / min, and anaerobic fermentation was carried out; after fermentation, the fermentation broth was placed in an 80℃ water bath for 15min to inactivate the bacterial strain and metabolic enzymes, and then cooled to room temperature to obtain the final fermentation broth.
[0038] Comparative Example 5 The difference between this comparative example and Example 1 is that the compound bacteria include Lactobacillus rhamnosus and Lactobacillus paracasei, and the ratio of the number of live Lactobacillus rhamnosus and Lactobacillus paracasei is 1:1.
[0039] Comparative Example 6 The difference between this comparative example and Example 1 is that the compound bacteria include Lactobacillus rhamnosus and Bacillus polymyxa, and the ratio of the number of live Lactobacillus rhamnosus and Bacillus polymyxa is 1:0.4.
[0040] Performance testing Black goji berry extracts prepared according to Examples 1-2 and Comparative Examples 1-6 from the same batch of black goji berries were subjected to the following tests. Referring to the patent "Preparation Method of Black Goji Berry Anthocyanin Extract and Lyophilized Powder," the anthocyanin content in the black goji berry extracts was determined using the pH differential method, and the total alkaloid content was determined using spectrophotometry. The performance test results are shown in Table 1.
[0041] Table 1 Performance Test Results
[0042] As shown in Table 1, the anthocyanin content in the black goji berry extracts of Examples 1-2 is 91.47-91.81 wt%, and the total alkaloid content is 1.03-1.12 wt%, which is higher than the product of the patent "Preparation method of black goji berry anthocyanin extract and freeze-dried powder".
[0043] The complex enzyme in Comparative Example 1 lacks β-glucosidase, which cannot effectively cleave the covalent bond between bound anthocyanins and glycosyl groups, and also affects the release of alkaloids, resulting in insufficient dissolution of anthocyanins and total alkaloids, with contents lower than in Example 1.
[0044] In Comparative Example 2, the excessively high proportion of β-glucosidase disrupted the synergistic balance of the complex enzymes, leading to a decrease in cell wall breakdown efficiency and a reduction in the yield of anthocyanins and total alkaloids.
[0045] In Comparative Example 3, the proportion of pectinase was too high and the proportion of β-glucosidase was too low. The cell wall middle layer was over-cleaved, but the conversion of bound anthocyanins and alkaloids was insufficient, which affected the extraction rate of both.
[0046] In Comparative Example 4, the aerobic fermentation step of Aspergillus niger was missing, resulting in incomplete breakdown of the residual cell wall structure and insufficient release of bound anthocyanins. At the same time, the dissolution of alkaloids was also affected, leading to a significant decrease in the content of anthocyanins and total alkaloids.
[0047] In Comparative Example 5, the ratio of Lactobacillus rhamnosus to Lactobacillus paracasei was unbalanced, the synergistic effect among lactic acid bacteria was weakened, the ability to modify and transform anthocyanins decreased, and the metabolic transformation of alkaloids was interfered with, resulting in a decrease in the content of both.
[0048] In Comparative Example 6, Lactobacillus paracasei was replaced with Bacillus polymyxa. Due to the mismatch in metabolic characteristics between Lactobacillus rhamnosus and Bacillus polymyxa, it was unable to effectively convert anthocyanin precursors and alkaloid-related components, resulting in a decrease in yield.
[0049] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A process for efficiently extracting anthocyanins from black goji berries, characterized in that, Includes the following steps: Step 1: Crush the dried black goji berries to obtain black goji berry powder; Step 2: Prepare black goji berry suspension; add compound enzyme to black goji berry suspension, perform enzymatic hydrolysis, inactivate enzyme, cool to obtain enzymatic hydrolysate; Step 3: Add Aspergillus niger to the enzymatic hydrolysate, ferment, sterilize, and obtain the primary fermentation broth; add compound bacteria to the primary fermentation broth, anaerobic ferment, sterilize, cool, and obtain the final fermentation broth; Step 4: Extract the final fermentation broth with alcohol to remove the ethanol and obtain a concentrated crude extract; Step 5: Purify and dry the concentrated crude extract to obtain black goji berry extract.
2. The process for efficiently extracting anthocyanins from black goji berries according to claim 1, characterized in that, Complex enzymes include cellulase, pectinase, and β-glucosidase.
3. The process for efficiently extracting anthocyanins from black goji berries according to claim 2, characterized in that, The mass ratio of cellulase: pectinase: β-glucosidase is 1:(0.5-0.6):(0.2-0.3).
4. The process for efficiently extracting anthocyanins from black goji berries according to claim 3, characterized in that, The conditions for enzymatic hydrolysis are: a hydrolysis temperature of 40-45℃ and a hydrolysis time of 70-90 min.
5. The process for efficiently extracting anthocyanins from black goji berries according to claim 1, characterized in that, The dosage of Aspergillus niger is (1-3) × 10 8 CFU / mL enzyme hydrolysate.
6. The process for efficiently extracting anthocyanins from black goji berries according to claim 5, characterized in that, The fermentation conditions for Aspergillus niger are: fermentation temperature of 30-35℃, stirring speed of 200-250r / min, aeration rate of 0.8-1.0vvm, and fermentation time of 60-80h.
7. The process for efficiently extracting anthocyanins from black goji berries according to claim 1, characterized in that, The complex bacteria include Lactobacillus rhamnosus and Lactobacillus paracasei.
8. The process for efficiently extracting anthocyanins from black goji berries according to claim 7, characterized in that, The ratio of viable Lactobacillus rhamnosus to Lactobacillus paracasei in the compound probiotics was 1:(0.3-0.5), and the dosage of the compound probiotics was (1-3)×10⁻⁶. 8 CFU / mL primary fermentation broth 9. The process for efficiently extracting anthocyanins from black goji berries according to claim 1, characterized in that, The conditions for anaerobic fermentation are: fermentation temperature 35-37℃, fermentation time 20-40h, and stirring speed 100-150r / min.
10. The process for efficiently extracting anthocyanins from black goji berries according to claim 1, characterized in that, The anthocyanin content in black goji berry extract is 91.47-91.81 wt%, and the total alkaloid content is 1.03-1.12 wt%.