Lactobacillus plantarum and application thereof in inhibiting degradation of anthocyanin

Abstract

The application discloses Lactiplantibacillus plantarum and application thereof in inhibiting degradation of anthocyanins, and belongs to the field of microbiology and food processing technology. The Lactiplantibacillus plantarum is classified as Lactiplantibacillus plantarum, and the strain number is HMSC1-1. The Lactiplantibacillus plantarum has been preserved in the China Center for Type Culture Collection on May 24, 2022, and the address is Wuhan University, No. 299, Bayi Road, Wuchang District, Wuhan City, Hubei Province, China. The preservation number is CCTCC NO: M2022711. When the Lactiplantibacillus plantarum is applied to inhibiting degradation of anthocyanins, a nutrition and health pickled yanghe product with high anthocyanin retention rate, stable color, and strong antioxidant activity can be prepared.

Description

Technical Field

[0001] This invention belongs to the field of biotechnology, and specifically relates to a plant lactobacillus and its application in inhibiting anthocyanin degradation. Background Technology

[0002] Zingiber striolatum Diels, also known as wild ginger, is a perennial herbaceous vegetable belonging to the ginger family (Zingiberaceae). It possesses various physiological activities, including hypoglycemic, antioxidant, antibacterial, and antitumor effects. As a seasonal vegetable, Zingiber striolatum is often pickled into kimchi, salted vegetables, and other preserved vegetables to extend its shelf life and meet year-round demand. Pickled vegetables made from fresh Zingiber striolatum have a unique flavor, are tender and crisp, and also offer antioxidant and hypoglycemic health benefits, making them a promising processed vegetable product with broad market development prospects.

[0003] Ginger lily contains abundant anthocyanins. Anthocyanins are polyphenols, which are not only important bioactive components of ginger lily but also its main coloring agents, giving it its unique color. However, anthocyanins are unstable and easily degraded. For example, during food processing, temperature, light, oxygen, metal ions, salt, and other additives can all affect the stability of anthocyanins. In addition, the pickling and fermentation process can also lead to a certain degree of degradation of anthocyanins in fermented fruits and vegetables.

[0004] The degradation of anthocyanins in pickled ginger lily will inevitably lead to a decrease in the product's antioxidant and other activities, resulting in a significant reduction in its health benefits, as well as deterioration in color and quality. However, the degradation of anthocyanins has not been given sufficient attention in the pickling and fermentation process of ginger lily. For example, Wang Shengsong et al. disclosed a processing method for pickled ginger lily (CN200810195173.8), and He Delong et al. disclosed the production process of pickled ginger lily (CN201710880398.6), neither of which addressed the issue of anthocyanin degradation.

[0005] As can be seen from the above, inhibiting the degradation of anthocyanins is a problem that urgently needs to be solved. Summary of the Invention

[0006] The purpose of this invention is to provide a plant lactobacillus that inhibits the degradation of anthocyanins.

[0007] To achieve the above-mentioned objectives, the technical solution of the present invention is as follows:

[0008] A plant-based Lactobacillus, characterized by its classification name Lactiplantibacillus plantarum, strain number HMSC1-1, was deposited on May 24, 2022, at the China Center for Type Culture Collection (CCTCC), located at Wuhan University, No. 299 Bayi Road, Wuchang District, Wuhan, Hubei Province, China, with accession number CCTCC NO: M2022711.

[0009] Lactic acid bacteria play an important role in the pickling and fermentation process of vegetables. They are not only beneficial to human health, but also promote the release and enhancement of polyphenolic compounds during plant-based fermentation. However, there is currently little research on the role of lactic acid bacteria in stabilizing anthocyanins and reducing their degradation.

[0010] In this invention, Lactobacillus plantarum HMSC1-1, which can inhibit anthocyanin degradation, was isolated and screened, thus reducing the degradation loss of anthocyanins in plants.

[0011] Therefore, the present invention also provides the application of *Lactobacillus plantarum* as described above in inhibiting anthocyanin degradation.

[0012] This invention also provides a method for preparing a fermented product of *Ligusticum striatum*, comprising the following steps:

[0013] (1) Fresh ginger lily was pretreated to obtain a pretreated product;

[0014] (2) Preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge;

[0015] (3) The Lactobacillus plantarum HMSC1-1 bacterial sludge was resuspended in sterile water and evenly dispersed on the surface of the pretreated product. It was then sealed and placed in the dark for fermentation. During the fermentation process, the fermentation pH environment was weakly alkalized.

[0016] (4) After weakly alkalizing the fermentation pH environment, continue to ferment in a sealed container under dark conditions to obtain the product. This invention targets the specific functional component of anthocyanins in *Ligusticum striatum*. *Lactobacillus plantarum* HMSC1-1, which was isolated and screened, is inoculated onto *Ligusticum striatum*, thus stabilizing the anthocyanins in pickled *Ligusticum striatum*. This reduces the degradation and loss of anthocyanins during the pickling and fermentation process, alleviates the color deterioration of pickled *Ligusticum striatum*, and improves the antioxidant activity of the pickled *Ligusticum striatum* product.

[0017] There are various pretreatment methods in this invention. As a further preferred method, in step (1), the fresh *Zingiber officinale* is pretreated to obtain a pretreated product, including the following steps:

[0018] (1-1) After being slightly dehydrated, the ginger lily was placed in the fermentation liquid for acid washing and color protection treatment;

[0019] (1-2) Sprinkle salt on the citronella that has been slightly dehydrated and acid-washed for color protection, mix well, and then gently press to soften it to obtain the pretreated product.

[0020] As a further preferred option, in step (1-1), after the fresh ginger is slightly dehydrated, it is placed in the fermentation broth for acid washing and color protection treatment, specifically including:

[0021] After cleaning and trimming the fresh ginger, cut it into pieces according to their size and sun-dry it for 10-14 hours for slight dehydration. After slight dehydration, place it in the fermentation liquid for acid washing and color protection for 15-20 minutes.

[0022] As a further preferred embodiment, in step (1-1), the method for preparing the fermentation broth includes:

[0023] Ferment the ginger lily for 3-5 days, retain the liquid portion produced during fermentation, add ascorbic acid to it, adjust the pH to 4.0-5.0, sterilize at 121℃ for 15 minutes, cool, and obtain the fermentation broth.

[0024] As a further preferred option, in step (1-2), the pickled and color-protected citronella is evenly sprinkled with 1.5-3.0% salt by weight, mixed well, and then gently pressed and softened for 6-8 hours to obtain the pretreated product.

[0025] As a further preferred embodiment, in step (2), the preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge includes:

[0026] Lactobacillus plantarum HMSC1-1 was cultured in MRS liquid medium for 48 h. HMSC1-1 was then centrifuged in a refrigerated centrifuge at a speed of 6000-8000 rpm for 10 minutes. After centrifugation, the supernatant was discarded, and the bacterial sludge was retained to obtain the Lactobacillus plantarum HMSC1-1 bacterial sludge.

[0027] As a further preferred embodiment, in step (3), the *Lactobacillus plantarum* HMSC1-1 bacterial sludge is resuspended in sterile water (10 μL). 7 -10 8 CFU / mL), at an inoculum concentration of 1-3% (v / w), is evenly spread on the surface of the pretreated product, sealed, and placed under dark conditions at 20-25℃ for pickling and fermentation. During the pickling and fermentation process, a weak alkalization treatment is carried out. On days 8-12 of pickling and fermentation, anhydrous sodium carbonate is used as a pH buffer to weakly alkalize the fermentation pH environment, so that the pH is maintained between 4.5 and 5.0 throughout the fermentation process. On days 28-32 of pickling and fermentation, the fermentation environment is weakly alkalized in the same way.

[0028] Through the above preparation method, the present invention can obtain a fermented product of *Ligusticum striatum* with high antioxidant activity and good color. Therefore, the present invention also provides a fermented product of *Ligusticum striatum* prepared by the above preparation method.

[0029] Compared with the prior art, the beneficial effects of the present invention are reflected in:

[0030] (1) In this invention, the content of anthocyanins such as proanthocyanidins C1, B2, B1, kaempferol, and demethoxycyanidin 7-O-rutin in the pickled ginger lily produced after acid washing for color protection, inoculation with strain HMSC1-1, and weakly alkaline dry fermentation is significantly increased. This indicates that acid washing for color protection, inoculation with strain HMSC1-1, and weakly alkaline dry fermentation can inhibit the degradation of anthocyanins, resulting in better color. Therefore, this invention produces a nutritious and healthy pickled ginger lily product with high anthocyanin retention, stable color, and strong antioxidant activity.

[0031] (2) The DPPH free radical scavenging rate and FRAP reduction capacity of pickled and fermented citronella with pure inoculation of lactic acid bacteria HMSC1-1 were significantly increased compared with naturally fermented citronella, indicating that the inoculated strain HMSC1-1 in this invention can improve the antioxidant activity of citronella, inhibit the degradation of anthocyanins, and make the product have better color. Attached Figure Description

[0032] Figure 1 The colony morphology of Lactobacillus plantarum HMSC1-1 in Example 1 is shown.

[0033] Figure 2 Image of pickled lily products [Left: Fermented without inoculation with Lactobacillus plantarum HMSC1-1 in Example 3 of this invention; Right: Fermented with inoculation with Lactobacillus plantarum HMSC1-1 in Example 2 of this invention].

[0034] Figure 3 A comparison chart of DPPH free radical scavenging rates for pickled ginger products.

[0035] Figure 4 Comparison chart of FRAP reduction capacity for pickled ginger products. Detailed Implementation

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1

[0038] This embodiment describes the screening of lactic acid bacteria that have the ability to stabilize anthocyanins from lotus flowers. The method includes the following steps:

[0039] (1) Determination of total anthocyanins: Using cyanidin glucoside as a standard, the samples were diluted with hydrochloric acid-potassium chloride buffer at pH 1.0 and acetate-sodium acetate buffer at pH 4.5, respectively. After equilibration, the absorbance of the two buffers was measured at the maximum absorption wavelength. The total anthocyanin content was expressed as cyanidin glucoside content.

[0040] (2) Preparation of ginger vegetable pulp: After washing and cutting the fresh ginger, add purified water in a pulping machine at a material-to-liquid ratio of 1:3, and pulp it. Dispense it into sterile blue cap bottles, seal them, sterilize them in a water bath at 85-90℃ for 15 minutes, and cool them for later use.

[0041] (3) Lactic acid bacteria culture: Lactic acid bacteria were inoculated into MRS broth medium and cultured at 37℃ for 24 hours to obtain fermentation broth, which was then prepared into a bacterial suspension (10... 7 (CFU / mL)

[0042] (4) Inoculation: The lactic acid bacteria suspension was inoculated into the *Ligustrum lucidum* vegetable pulp at 5% (v / v) and fermented at 37℃ for 72 h. After fermentation, the anthocyanin content was measured. The anthocyanin content in the fermented *Ligustrum lucidum* vegetable pulp was highest after testing by HMSC1-1. The strain was identified as *Lactiplantibacillus plantarum*, and the 16S rRNA sequence of *Lactiplantibacillus plantarum* HMSC1-1 is shown in SEQ. NO. 1. *Lactiplantibacillus plantarum* HMSC1-1 was deposited on May 24, 2022, at the China Center for Type Culture Collection (CCTCC), located at Wuhan University, No. 299 Bayi Road, Wuchang District, Wuhan, Hubei Province, China, with accession number CCTCC NO: M2022711.

[0043] Example 2

[0044] This embodiment describes a method for preparing a fermented product of *Ligusticum striatum*, comprising the following steps:

[0045] I. Acid washing and color protection of ginger lily fermentation liquid, specifically including the following steps:

[0046] 1) Preparation of fermentation broth: Mix fresh ginger and 3% saline at a ratio of 1:3 (w / v), ferment at room temperature for 3-5 days, pour out the fermentation broth, add ascorbic acid to make the pH between 4.0 and 5.0, sterilize at 121℃ for 15 minutes, cool, and set aside.

[0047] 2) Raw material pretreatment: After cleaning and trimming the fresh ginger, cut it into pieces according to the size of the pieces, and sun-dry for 10-14 hours for slight dehydration.

[0048] 3) Pickling and color protection of ginger: Place the treated ginger in the above fermentation liquid for pickling and color protection for 15-20 minutes, and set aside.

[0049] II. The application of *Lactobacillus plantarum* HMSC1-1 obtained in Example 1 in reducing the degradation of anthocyanins in pickled lotus flowers includes the following steps:

[0050] 1) Raw material softening: Evenly sprinkle 1.5-3.0% salt into the pickled and color-protected ginger lily according to the weight ratio, mix well, and then gently press to soften for 6-8 hours.

[0051] 2) Preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge: Lactobacillus plantarum HMSC1-1 was cultured in MRS liquid medium for 48 h, centrifuged in a refrigerated centrifuge (centrifugation speed 6000-8000 rpm, centrifugation for 10 minutes), the upper bacterial liquid was discarded, and the bacterial sludge was reserved for use.

[0052] 3) Pickling and fermentation: Resuspend the centrifuged mycelium slurry in sterile water (10... 7 -10 8 CFU / mL), evenly spread on the surface of the lily at an inoculum concentration of 1-3% (v / w), cover and seal, and place in a dark environment at 20-25℃ for pickling and fermentation.

[0053] 4) Slight alkalization during fermentation: Slight alkalization is carried out during the pickling and fermentation of dried ginger lily. Around the 10th day of pickling and fermentation, anhydrous sodium carbonate is used as a pH buffer to slightly alkalize the fermentation pH environment, so that the pH is maintained between 4.5 and 5.0 throughout the fermentation process. On the 30th day of pickling and fermentation, the fermentation environment is slightly alkalized in the same way. Then, the ginger lily is compacted, sealed and placed in the dark to continue fermentation to obtain the product.

[0054] Example 3

[0055] The difference between this embodiment and Embodiment 2 is that HMSC1-1 was not inoculated during the pickling and fermentation process of *Zingiber officinale*, and no weak alkalization treatment was performed. The steps include:

[0056] I. Acid washing and color protection of ginger lily fermentation liquid, specifically including the following steps:

[0057] 1) Preparation of fermentation broth: Mix fresh ginger and 3% saline at a ratio of 1:3 (w / v), ferment at room temperature for 3-5 days, pour out the fermentation broth, add ascorbic acid to make the pH between 4.0 and 5.0, sterilize at 121℃ for 15 minutes, cool, and set aside.

[0058] 2) Raw material pretreatment: After cleaning and trimming the fresh ginger, cut it into pieces according to the size of the pieces, and sun-dry for 10-14 hours for slight dehydration.

[0059] 3) Pickling and color protection of ginger: Place the treated ginger in the above fermentation liquid for pickling and color protection for 15-20 minutes, and set aside.

[0060] II. Natural pickling and fermentation of ginger lily includes the following steps:

[0061] 1) Raw material softening: Evenly sprinkle 1.5-3.0% salt into the pickled and color-protected ginger lily according to the weight ratio, mix well, and then gently press to soften for 6-8 hours.

[0062] 2) Pickling and fermentation: After sealing, place in a dark environment at a temperature of 20-25℃ for pickling and fermentation.

[0063] Example 4

[0064] The difference between this embodiment and Embodiment 2 is that the acid washing and color-protecting treatment with catnip and the weak alkalization treatment during fermentation were not performed. The steps include:

[0065] 1) Raw material pretreatment: After cleaning and trimming the fresh ginger, cut it into pieces according to the size of the pieces, and sun-dry for 10-14 hours for slight dehydration.

[0066] 2) Raw material softening: Sprinkle 1.5-3.0% salt evenly over the dehydrated citronella by weight, mix well, and then gently press to soften for 6-8 hours.

[0067] 3) Preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge: Lactobacillus plantarum HMSC1-1 was cultured in MRS liquid medium for 48 h, centrifuged in a refrigerated centrifuge (centrifugation speed 6000-8000 rpm, centrifugation for 10 minutes), the upper bacterial liquid was discarded, and the bacterial sludge was reserved for use.

[0068] 4) Pickling and fermentation: Resuspend the centrifuged mycelium slurry in sterile water (10... 7 -10 8 CFU / mL), evenly spread on the surface of the lily at an inoculum concentration of 1-3% (v / w), cover and seal, and place in a dark environment at 20-25℃ for pickling and fermentation.

[0069] Example 5

[0070] The difference between this embodiment and Embodiment 2 is that no acid pickling and color-protecting treatment with cationic acid was performed. The steps include:

[0071] 1) Raw material pretreatment: After cleaning and trimming the fresh ginger, cut it into pieces according to the size of the pieces, and sun-dry for 10-14 hours for slight dehydration.

[0072] 2) Raw material softening: Sprinkle 1.5-3.0% salt evenly over the dehydrated citronella by weight, mix well, and then gently press to soften for 6-8 hours.

[0073] 3) Preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge: Lactobacillus plantarum HMSC1-1 was cultured in MRS liquid medium for 48 h, centrifuged in a refrigerated centrifuge (centrifugation speed 6000-8000 rpm, centrifugation for 10 minutes), the upper bacterial liquid was discarded, and the bacterial sludge was reserved for use.

[0074] 4) Pickling and fermentation: Resuspend the centrifuged mycelium slurry in sterile water (10... 7 -10 8 CFU / mL), evenly spread on the surface of the lily at an inoculum concentration of 1-3% (v / w), cover and seal, and place in a dark environment at 20-25℃ for pickling and fermentation.

[0075] 5) Slight alkalization during fermentation: Slight alkalization treatment is carried out during the pickling and fermentation of dried ginger lily. Around the 10th day of pickling and fermentation, anhydrous sodium carbonate is used as a pH buffer to slightly alkalize the fermentation pH environment, so that the pH is maintained between 4.5 and 5.0 throughout the fermentation process. On the 30th day of pickling and fermentation, the fermentation environment is slightly alkalized in the same way. Then, the ginger lily is compacted, sealed and placed in the dark to continue fermentation to obtain the product.

[0076] Example 6

[0077] The difference between this embodiment and Embodiment 2 is that the weak alkalization treatment during fermentation was not performed. The steps include:

[0078] I. Acid washing and color protection of ginger lily fermentation liquid, specifically including the following steps:

[0079] 1) Preparation of fermentation broth: Mix fresh ginger and 3% saline at a ratio of 1:3 (w / v), ferment at room temperature for 3-5 days, pour out the fermentation broth, add ascorbic acid to make the pH between 4.0 and 5.0, sterilize at 121℃ for 15 minutes, cool, and set aside.

[0080] 2) Raw material pretreatment: After cleaning and trimming the fresh ginger, cut it into pieces according to the size of the pieces, and sun-dry for 10-14 hours for slight dehydration.

[0081] 3) Pickling and color protection of ginger: Place the treated ginger in the above fermentation liquid for pickling and color protection for 15-20 minutes, and set aside.

[0082] II. The application of *Lactobacillus plantarum* HMSC1-1 obtained in Example 1 in reducing the degradation of anthocyanins in pickled lotus flowers includes the following steps:

[0083] 1) Raw material softening: Evenly sprinkle 1.5-3.0% salt into the pickled and color-protected ginger lily according to the weight ratio, mix well, and then gently press to soften for 6-8 hours.

[0084] 2) Preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge: Lactobacillus plantarum HMSC1-1 was cultured in MRS liquid medium for 48 h, centrifuged in a refrigerated centrifuge (centrifugation speed 6000-8000 rpm, centrifugation for 10 minutes), the upper bacterial liquid was discarded, and the bacterial sludge was reserved for use.

[0085] 3) Pickling and fermentation: Resuspend the centrifuged mycelium slurry in sterile water (10... 7 -10 8 CFU / mL), evenly spread on the surface of the lily at an inoculum concentration of 1-3% (v / w), cover and seal, and place in a dark environment at 20-25℃ for pickling and fermentation.

[0086] Comparison and summary

[0087] In Examples 2-6, the contents of proanthocyanidins C1, B2, kaeracyanin, and demethoxycyanidin 7-O-rutin, as well as their DPPH free radical scavenging capacity and FRAP reducing capacity in *Heliotropium indicum* were determined. The results are shown in Table 1. Figures 2-4 .

[0088] Table 1. Content of main anthocyanins in pickled ginger lily products

[0089]

[0090] From Table 1 and Figure 2 As can be seen from the above, compared with Examples 3-6, the anthocyanin content of proanthocyanidins C1, B2, B1, Kayla anthocyanin, and demethoxycyanidin 7-O-rutin glycoside in the *Zingiber officinale* obtained in Example 2 was significantly increased after acid washing and color protection, inoculation with strain HMSC1-1, and weakly alkaline dry fermentation. This indicates that acid washing and color protection, inoculation with strain HMSC1-1, and weakly alkaline dry fermentation can inhibit the degradation of anthocyanins and result in better color.

[0091] In addition, from Figure 3 and Figure 4 The results show that the DPPH free radical scavenging ability and FRAP reducing ability of ginger lily inoculated with lactic acid bacteria HMSC1-1 are significantly increased compared with naturally fermented ginger lily. This indicates that the inoculated strain HMSC1-1 can improve the antioxidant activity of ginger lily. Among them, ginger lily that has undergone acid washing and color protection, inoculated with strain HMSC1-1 and weakly alkaline dry fermentation has the highest antioxidant activity, giving the product better nutritional value.

Claims

1. A type of Lactobacillus plantarum, characterized in that, Category naming Lactiplantibacillus plantarum The strain number is HMSC1-1, which was deposited on May 24, 2022 at the China Center for Type Culture Collection (CCTCC), located at Wuhan University, No. 299 Bayi Road, Wuchang District, Wuhan, Hubei Province, China, with accession number CCTCC NO: M2022711.

2. The application of *Lactobacillus plantarum* as described in claim 1 in inhibiting anthocyanin degradation.

3. A method for preparing a fermented product of *Ligusticum striatum*, characterized in that, Includes the following steps: (1) Fresh ginger lily was pretreated to obtain a pretreated product; (2) Prepare *Lactobacillus plantarum* HMSC1-1 bacterial sludge as described in claim 1; (3) The Lactobacillus plantarum HMSC1-1 bacterial sludge was resuspended in sterile water and evenly dispersed on the surface of the pretreated product, sealed and placed in the dark for fermentation, and the fermentation pH environment was weakly alkalized during the fermentation process. (4) After the pH environment of weak alkalization fermentation is established, the product is continued to be sealed and placed in the dark for fermentation to obtain the product; In step (1), the fresh *Zingiber officinale* is pretreated to obtain a pretreated product, including the following steps: (1-1) After being slightly dehydrated, the ginger lily was placed in the fermentation broth for acid washing and color protection treatment; (1-2) Sprinkle salt on the citronella that has been slightly dehydrated and acid-washed for color protection, mix well, and then gently press to soften it to obtain the pretreated product.

4. The method for preparing the fermented product of *Ligusticum striatum* as described in claim 3, characterized in that, In step (1-1), after the ginger lily undergoes micro-dehydration, it is placed in the fermentation broth for acid washing and color protection treatment, specifically including: After being slightly dehydrated, the ginger lily is placed in the fermentation broth for acid washing and color protection for 15-20 minutes.

5. The method for preparing the fermented product of *Ligusticum striatum* as described in claim 4, characterized in that, In step (1-1), the method for preparing the fermentation broth includes: Ferment the ginger lily for 3-5 days, retain the fermentation broth, add ascorbic acid to adjust the pH to 4.0-5.0, sterilize at 121℃ for 15 minutes, cool, and obtain the fermentation broth.

6. The method for preparing the fermented product of *Ligusticum striatum* as described in claim 5, characterized in that, In steps (1-2), the slightly dehydrated and acid-washed citronella is evenly sprinkled with 1.5-3.0% salt by weight, mixed well, and then gently pressed to soften for 6-8 hours to obtain the pretreated product.

7. The method for preparing the fermented product of *Ligusticum striatum* as described in claim 3, characterized in that, In step (2), the preparation of Lactobacillus plantarum HMSC1-1 bacterial sludge includes: Lactobacillus plantarum HMSC1-1 was cultured in MRS liquid medium for 48 h. HMSC1-1 was then centrifuged in a refrigerated centrifuge at a speed of 6000-8000 rpm for 10 minutes. After centrifugation, the supernatant was discarded, and the bacterial sludge was retained to obtain the Lactobacillus plantarum HMSC1-1 bacterial sludge.

8. The method for preparing the fermented product of *Ligusticum striatum* as described in claim 3, characterized in that, In step (3), the *Lactobacillus plantarum* HMSC1-1 bacterial sludge is resuspended in sterile water and evenly spread on the surface of the pretreated product at an inoculation rate of 1-3% (v / w). After being sealed, it is placed in a dark environment at 20-25℃ for pickling and fermentation. During the pickling and fermentation process, a weak alkalization treatment is carried out. On days 8-12 of the pickling and fermentation, anhydrous sodium carbonate is used as a pH buffer to weakly alkalize the fermentation pH environment, so that the pH is maintained between 4.5 and 5.0 throughout the fermentation process. On days 28-32 of the pickling and fermentation, the fermentation environment is weakly alkalized in the same way.

9. A fermented product of *Ligusticum striatum* prepared by the method for preparing fermented products of *Ligusticum striatum* as described in any one of claims 3-8.

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