Jaboticaba extract fermented by lactic acid bacteria and its preparation method

Abstract

The present invention relates to a jaboticaba extract fermented by lactic acid bacteria and a preparation method thereof. After the jaboticaba is fermented by Lactobacillus plantarum, the extract has better antioxidant, whitening and anti-photoaging effects and can be applied to cosmetics or skin care products.

Description

Technical Field

[0001] The present invention relates to a jaboticaba extract fermented by lactic acid bacteria and a preparation method thereof. Specifically, it relates to a jaboticaba extract fermented by lactic acid bacteria for antioxidant, whitening and anti-photoaging applications and a preparation method thereof. Background Art

[0002] Lactic acid bacteria generally refer to the general term for bacteria that can utilize carbohydrates for fermentation to produce a large amount of lactic acid. Among them, there are different categories such as Lactobacillus, Leuconostoc, and Streptococcus. In the past, it was found that when food is fermented by lactic acid bacteria, it will have a special flavor and enhance the beneficial flora in the human body, so it is widely used in food and health food.

[0003] Lactobacillus plantarum is a Gram-positive facultative anaerobe and exists in various vegetable fermentations (such as pickles and sauerkraut). The growth environment is at a culture temperature of 15-45°C, and it can produce two optical isomers of lactic acid, D / L.

[0004] The origin of jaboticaba is Brazil, South America. Its name is transliterated from the English Jaboticaba, scientific name: Pliniacauliflora, old scientific name Myrciaria cauliflora. It is a tropical and subtropical fruit, an evergreen fruit tree with lush branches and leaves throughout the year. The flower is a small white flower, and the fruit resembles a grape but densely fruits on the trunk, so it is also called tree grape.

[0005] The fruiting season of jaboticaba is from April to June and from September to December. It has a special flavor, the pulp is semi-transparent, and contains one seed. Some studies have found that jaboticaba is rich in various phenolic compounds, including anthocyanins, flavonoids, tannins, phenolic acids, and polyphenols. It has rich vitamins that can enhance resistance and reduce the harm of diseases to the body. It contains rich vitamin B groups that can maintain the normal function of the nervous system.

[0006] The skin will gradually oxidize and age with the increase of age and internal and external factors. The internal factors mainly come from mental stress, fatigue, insomnia, staying up late, worry, etc.; external factors include: ultraviolet rays, air pollution, and unbalanced diet and lack of nutrition. In order to delay aging, people have begun to pay attention to ingesting natural fruits with antioxidant effects.

[0007] In order to meet the needs of some customer groups in modern society, the industry has long discovered the development of whitening products with high commercial value. In recent years, research has found that inhibiting tyrosinase to reduce melanin production is an effective whitening mechanism. In order to find natural compounds with whitening effects, observing the inhibitory power of tyrosinase using in vitro and cell tests is a reference method.

[0008] Therefore, in order to effectively extract natural compounds with whitening effects from natural fruits, a new preparation method needs to be developed. Summary of the Invention

[0009] In view of the above problems, the purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art, and further provide a natural fruit extract with better antioxidant and whitening effects.

[0010] First, Lactobacillus plantarum is cultured in a vegetarian MRS broth medium derived from vegetables. The commonly used MRS broth medium for Lactobacillus plantarum contains animal sources, and the peptone in it is obtained from cows or pigs, which is non-vegetarian; the MRS broth medium containing peptone from pigs does not meet the halal certification. Therefore, the present invention ferments Lactobacillus plantarum with a vegetarian MRS broth medium derived from jaboticaba and vegetables, and develops a vegetarian jaboticaba extract fermented by lactic acid bacteria with antioxidant and whitening effects and its preparation method.

[0011] There is currently no relevant research report on the anti-photoaging effect of jaboticaba after fermentation by lactic acid bacteria. The jaboticaba extract fermented by lactic acid bacteria of the present invention can reduce the damage of DNA breakage caused by UVB irradiation, and thus achieve the effect of anti-photoaging. In particular, the photo-protective ability can be greater than 62%.

[0012] The experimental results confirm that the jaboticaba extract fermented by lactic acid bacteria obtained under specific preparation conditions has better antioxidant, whitening effects and photo-protective ability, and its effects can be greatly improved, and it can be used in the application of cosmetics or skin care products for antioxidant, repair, whitening and photo-protection.

[0013] Hereinafter, through specific embodiments in conjunction with the accompanying drawings, it will be described in detail to facilitate a better understanding of the purpose, technical content, characteristics and achieved effects of the present invention. Brief Description of the Drawings

[0014] The present invention will be further described below in conjunction with the accompanying drawings:

[0015] Figure 1 It is a schematic diagram of the lactic acid content after fermenting a composition of jaboticaba, culture medium and water in different proportions with lactic acid bacteria;

[0016] Figure 2 It is a schematic diagram of lactic acid content after fermentation under the conditions of using a composition of jaboticaba, culture medium and water in a specific ratio, whether the jaboticaba is sterilized, whether lactic acid bacteria are added, and the condition of not adding jaboticaba and only adding lactic acid bacteria;

[0017] Figure 3 It is a schematic diagram of the DPPH free radical scavenging ability of the jaboticaba extract fermented by lactic acid bacteria under different conditions and the extract obtained by fermentation under the condition of not adding jaboticaba and only adding lactic acid bacteria;

[0018] Figure 4 It is a schematic diagram of the total reducing power of the jaboticaba extract fermented by lactic acid bacteria under different conditions and the extract obtained by fermentation under the condition of not adding jaboticaba and only adding lactic acid bacteria;

[0019] Figure 5 It is a schematic diagram of the total phenolic content of the jaboticaba extract fermented by lactic acid bacteria under different conditions and the extract obtained by fermentation under the condition of not adding jaboticaba and only adding lactic acid bacteria;

[0020] Figure 6 It is a schematic diagram of the tyrosinase inhibitory ability of the jaboticaba extract fermented by lactic acid bacteria under different conditions and the extract obtained by fermentation under the condition of not adding jaboticaba and only adding lactic acid bacteria;

[0021] Figure 7 It is a schematic diagram of the cell viability test using the jaboticaba extract fermented by lactic acid bacteria with the best tyrosinase inhibitory ability;

[0022] Figure 8 It is a schematic diagram of the photoprotective ability test using the jaboticaba extract fermented by lactic acid bacteria with the best tyrosinase inhibitory ability. Detailed implementation mode

[0023] The following content will combine the accompanying drawings and illustrate the technical content of the present invention through specific specific embodiments. Those familiar with this technology can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0024] Experimental materials

[0025] 1. Jaboticaba (Plinia cauliflora), obtained from Nantou area, Taiwan, China.

[0026] 2. The lactic acid bacteria used is Lactobacillus plantarum with a deposit number of BCRC 10069.

[0027] 3. The MRS broth medium used is a vegetarian MRS broth medium (HiMedia@HiVeg MV369) sourced from vegetables.

[0028] Example 1

[0029] Screening of the fermentation ratio of jaboticaba

[0030] 1. Inoculum culture: Lactobacillus plantarum (BCRC 10069) was cultured in a 5.5 wt% MRS broth medium (HiMedia@HiVeg MV369) for 18 - 24 hours, preferably 21 hours; the temperature for culturing the inoculum was 35°C, and the rotation speed of the incubator was 50 - 150 rpm, preferably 150 rpm.

[0031] 2. Jaboticaba fermentation: After sterilizing 1 - 2.5 wt% of the MRS broth medium (HiMedia@HiVeg MV369) and 47.5 - 69 wt% of water, 30 - 50 wt% of jaboticaba was added, and 5 wt% of the inoculum bacterial solution was added to each experimental group of the composition containing different proportions of jaboticaba, medium, and water, and fermentation was carried out at 35°C for 24 hours with the rotation speed of the incubator being 150 rpm. The formulation is shown in Table 1 below.

[0032] Proportion screening experimental group J1 J2 J3 J4 J5 J6 J7 Jaboticaba (wt%) 30 30 30 40 50 40 50 Culture medium (wt%) 2.5 1.5 1 2.5 2.5 1.5 1.3 Water (wt%) 67.5 68.5 69 57.5 47.5 58.5 48.7 Total (wt%) 100 100 100 100 100 100 100

[0033] 3. Extraction: The obtained jaboticaba fermented product was centrifuged using a high - speed centrifuge at a rotation speed of 1300 - 3600 rpm, preferably 3000 rpm; centrifugation was carried out for 15 - 40 minutes, preferably 20 - 35 minutes; the supernatant obtained after centrifugation was used for subsequent tests.

[0034] 4. Lactic acid content analysis: The supernatant (i.e., the fermentation product) obtained after centrifuging the jaboticaba fermented products of each group above was diluted 100 times with methanol, filtered through a 0.22 μm filter membrane, and the lactic acid content was detected by HPLC. Column used: synergi fusion - RP (150x4.6mm), temperature 25°C, injection volume 1 μL, flow rate 1 mL / min, mobile phase: phosphoric acid - methanol solution.

[0035] Reference Figure 1 , Figure 1The figure shows the schematic diagram of the lactic acid content after fermenting the composition of jaboticaba, culture medium and water with different ratios by lactic acid bacteria. It can be seen from the figure that the lactic acid content of the J1 formula is the highest, about 2.38%; therefore, subsequent process optimization, antioxidant and whitening tests are carried out with the J1 formula.

[0036] Example 2

[0037] Process optimization

[0038] During the fermentation process, there are natural microorganisms in the fruit itself, mostly yeasts and lactic acid bacteria, and these bacteria have a symbiotic characteristic with the MRS broth culture medium and the Lactobacillus plantarum (BCRC10069) used in the present invention. Therefore, the differences in fermentation under the conditions of sterilized or non-sterilized jaboticaba, with or without inoculation, and only inoculation without putting jaboticaba are compared. The experimental formulas are shown in Table 2 below.

[0039] Table 2

[0040]

[0041] 1. Inoculum culture: The Lactobacillus plantarum (BCRC 10069) is cultured in a 5.5 wt% MRS broth culture medium (HiMedia@HiVeg MV369) for 18 - 24 hours, preferably 21 hours; the temperature for culturing the inoculum is 35°C, and the rotation speed of the incubator is 50 - 150 rpm, preferably 150 rpm.

[0042] 2. Jaboticaba fermentation: The processes are compared in groups of non-sterilized jaboticaba, jaboticaba sterilized together with the MRS broth culture medium, fermentation without inoculation, and only inoculation without putting jaboticaba. After sterilizing 2.5 wt% of the MRS broth culture medium (HiMedia@HiVeg MV369) and 67.5 wt% of water or 97.5 wt% of water (blank group with only inoculation and no jaboticaba), 30 wt% of jaboticaba is added, and 5 wt% of the inoculum solution is added to each experimental group. Fermentation is carried out at 35°C for 24 hours, and the rotation speed of the incubator is 150 rpm. The formula is shown in Table 2 above.

[0043] 3. Extraction: The obtained experimental groups of jaboticaba fermented products and fermented products with only inoculation are centrifuged using a high-speed centrifuge at a rotation speed of 1300 - 3600 rpm, preferably 3000 rpm; centrifugation is carried out for 15 - 40 minutes, preferably 20 - 35 minutes; the supernatant obtained after centrifugation is used for subsequent tests.

[0044] Refer to Figure 2 , Figure 2Shown is a schematic diagram of the lactic acid content after fermentation under the conditions of using a composition of jaboticaba, culture medium, and water in a specific ratio, with whether the jaboticaba is sterilized, whether lactic acid bacteria are added, and the condition of not adding jaboticaba and only adding lactic acid bacteria; since no lactic acid content was measured in the groups of J1-1N and J1-2N without added inoculum, therefore Figure 2 only the three groups of data of J1-1, J1-2, and J1-2C are available. It can be seen from the figure that the lactic acid contents of the three groups of J1-1, J1-2, and J1-2C are 2.32%, 2.23%, and 0.95% in sequence, indicating that in the jaboticaba extract fermented by lactic acid bacteria, there is little difference in the lactic acid content produced with or without sterilization, and at least more than 2% of lactic acid can be produced. Therefore, further evaluation of the efficacy is carried out.

[0045] Example 3

[0046] DPPH antioxidant capacity analysis

[0047] The fermentation extracts obtained from the five groups of the process optimization experimental group J1-1 to J1-2C in Example 2 were respectively diluted to 0.625%, 1.25%, 2.5%, 5%, and 10% for the DPPH free radical scavenging test, and the results are as Figure 3 shown; it can be seen from the figure that the lower the concentration of each group, the lower the DPPH free radical scavenging ability, and when the J1-2 group is diluted to 0.625%, it is still higher than other groups, and the scavenging ability is greater than 20%.

[0048] Then, IC 50 was calculated from the above experimental results, and IC 50 is the concentration required to inhibit 50% of DPPH free radicals. The lower the concentration, the stronger the antioxidant capacity. Referring to Table 3 below, when reaching IC 50 , the required concentrations of each group of J1-1 to J1-2C are 2.38%, 1.56%, 5.67%, 2.19%, and 42.35% in sequence, and among them, the free radical scavenging ability of this group of J1-2 is the best.

[0049] Table 3

[0050]

[0051]

[0052] Example 4

[0053] Total reducing power test

[0054] The fermentation extracts obtained from the five groups of the process optimization experimental group J1-1 to J1-2C in Example 2 were subjected to the total reducing power test. Referring to Figure 4 , Figure 4The figure shows the total reducing power of jaboticaba extracts fermented by lactic acid bacteria under different conditions, as well as the extracts obtained by fermentation under the condition of adding only lactic acid bacteria without jaboticaba. It can be seen from the figure that the total reducing power (mg of gallic acid equivalent (GAE) / g) of each gram of fermented extract obtained by fermentation of the five groups J1-1 to J1-2C in the process optimization experimental group relative to gallic acid is approximately 1.0 mg, 1.4 mg, 0.9 mg, 1.2 mg, and 0.2 mg in sequence; this result shows that the J1-2 group is better than the J1-1 group, and the fermented groups (J1-1, J1-2) are better than the non-inoculated groups (J1-1N, J1-2N). In addition, it can be known from the comparison of the blank group (J1-2C) that the total reducing power can be improved by fermenting jaboticaba with lactic acid bacteria (i.e., Lactobacillus plantarum, deposit number BCRC 10069). The total reducing power of the J1-2 group is 7 times that of the J1-2C group.

[0055] Example 5

[0056] Total phenol content test

[0057] The content of phenolic compounds in the five groups J1-1 to J1-2C of the process optimization experimental group was detected with a phenolic indicator (Folin-Ciocalteu's phenol reagent); if phenolic compounds are contained in each group, they will react with the phenolic indicator to develop color at a wavelength of 750 nm. The higher the absorbance value, the more polyphenols are contained in the sample and the stronger the antioxidant ability. In this test, gallic acid was used as the positive control group to compare the relative total phenol content of each group of J1-1 to J1-2C of the present invention with respect to gallic acid (positive control group).

[0058] Reference Figure 5 , Figure 5 The figure shows the total phenol content of jaboticaba extracts fermented by lactic acid bacteria under different conditions, as well as the extracts obtained by fermentation under the condition of adding only lactic acid bacteria without jaboticaba. It can be seen from the figure that the total phenol content of the fermented extracts obtained by fermentation of the five groups J1-1 to J1-2C in the process optimization experimental group is approximately 1.0, 1.6, 1.1, 2.0, and 0.1 (mg of GAE / g) in sequence; this result shows that the J1-2 group is better than the J1-1 group, but the non-inoculated groups (J1-1N, J1-2N) are better than the fermented groups (J1-1, J1-2). Because jaboticaba itself contains a large amount of phenolic compounds, it is speculated that the high phenol content is caused by the fact that jaboticaba is not fermented by microorganisms. And it is found through experiments that the less the total phenol content, the stronger the DPPH antioxidant ability, which further confirms that Lactobacillus plantarum (BCRC 10069) will absorb phenolic compounds in jaboticaba and produce other antioxidant substances.

[0059] Example 6

[0060] In vitro tyrosinase inhibition assay

[0061] The fermentation extracts obtained from the process optimization experimental groups J1-1 to J1-2C were diluted by 0.5%, 1%, 2% and 5% respectively for the in vitro tyrosinase inhibition assay, and the experimental results were calculated to obtain IC 50 , IC 50 is the concentration required to inhibit 50% of tyrosinase. The lower the concentration, the stronger the tyrosinase inhibition ability. Referring to Table 4 below, when reaching IC 50 , the required concentrations of each group of J1-1 to J1-2C are 4.28%, 3.99%, 7.69%, 5.06% and 11.61% in sequence. Among them, the tyrosinase inhibition ability of the J1-2 group is the best. This result shows that the J1-2 group is better than the J1-1 group, and the fermented groups (J1-1, J1-2) are better than the non-inoculated groups (J1-1N, J1-2N); in addition, it can be seen from the comparison of the blank group (J1-2C) that jaboticaba fermented by lactic acid bacteria (i.e., Lactobacillus plantarum, deposit number BCRC 10069) can enhance the inhibition of in vitro tyrosinase activity, and the tyrosinase inhibition ability of the J1-2 group is 2.9 times that of the J1-2C group.

[0062] Group <![CDATA[IC 50 (wt%)]]> J1-1 4.28 J1-2 3.99 J1-1N 7.69 J1-2N 5.06 J1-2C 11.61

[0063] Example 7

[0064] Tyrosinase inhibition in cells

[0065] B16F10 mouse skin melanoma cells with a cell density of 5×10 4 cells / well were seeded into a 24-well culture plate and placed in an incubator at 37°C and 5% CO 2 for 24 hours; then each group of J1-1 to J1-2C was replaced and added to the 24-well culture plate, and placed in an incubator at 37°C and 5% CO 2 for 24 hours. The tyrosinase enzyme was centrifuged and taken out for testing with L-DOPA. The experimental results were calculated to obtain IC 50 , IC 50 is the concentration required to inhibit 50% of tyrosinase. The lower the concentration, the stronger the tyrosinase inhibition ability.

[0066] Referring to Figure 6 , Figure 6 is a schematic diagram of the tyrosinase inhibitory power of jaboticaba extracts fermented by lactic acid bacteria under different conditions and extracts obtained by fermentation under the condition of not adding jaboticaba and only adding lactic acid bacteria. When reaching IC 50When the concentrations required for each group of J1-1 to J1-2C are 0.67%, 0.31%, 1.84%, 1.61% and 4.21% in sequence, among which the tyrosinase inhibitory ability of the J1-2 group is the best. This result shows that the fermented groups (J1-1, J1-2) are superior to the non-inoculated groups (J1-1N, J1-2N), and the tyrosinase inhibitory ability of the J1-2 group is 5.19 times that of the J1-2N group, and the tyrosinase inhibitory ability of the J1-2 group is 13.6 times that of J1-2C.

[0067] Example 8

[0068] MTT assay (cell viability assay)

[0069] After diluting the fermentation extract obtained by fermenting the process optimization experimental group J1-2 to 2.5% and 0.625% respectively, the Hs68 cell viability assay (using MTT reagent) was carried out. Refer to Figure 7 , Figure 7 As shown in the figure, the schematic diagram of the cell viability assay was carried out with the jaboticaba extract fermented by lactic acid bacteria with the best tyrosinase inhibitory power. It can be seen from the figure that when the Hs68 cells were in the fermentation extract of the J1-2 group diluted to 2.5% and 0.625%, the cell viability was still higher than 80%. Therefore, it was determined that the fermentation extract of the J1-2 group had no cytotoxicity.

[0070] Example 9

[0071] Photo-protective ability test (UV light)

[0072] Using an alpha plate 24-well plate, 1x10 5 Hs68 cells with a volume of 500 μl were seeded in two plates. After at least 6 hours for the cells to adhere, all the old DMEM medium was removed, and 500 μl of fresh serum-free DMEM medium containing the fermentation extract of the J1-2 group diluted to 2.5% and 0.625% was replaced and cultured for 24 hours. The well plate was washed with PBS, and one plate of cells was sent into a nucleic acid fixator and irradiated with UVB 2.5 J / cm 2 . After the irradiation, the PBS was removed and 500 μl of fresh DMEM medium was replaced. After culturing for 3 hours, 50 μl of MTT reagent was added to each well, and then cultured for another 3 hours. The DMEM medium was removed, and 500 μl of DMSO was added to dissolve. Detection was carried out at an ELISA wavelength of 570 nm.

[0073] After diluting the fermentation extracts obtained from the process optimization experimental group J1-2 to 2.5% and 0.625% respectively, a photoprotective ability test of Hs68 cells was carried out. The positive control group was added with 5 ppm of silimarin, which is an antioxidant. Refer to Figure 8 , Figure 8 The schematic diagram of the photoprotective ability test was carried out with the jaboticaba extract fermented by lactic acid bacteria with the best tyrosinase inhibitory ability. As can be seen from the figure, after UV irradiation of Hs68 cells, the photoprotective ability of the blank group (C) was 0%, and the photoprotective abilities of the J1-2 group diluted to 2.5% and 0.625% were 62.62% and 37.48% in sequence. Therefore, it can be known from the test results that at a safe dose, as the concentration of the fermentation extract obtained from the J1-2 group fermentation increases, the photoprotective ability also increases accordingly, confirming that the jaboticaba extract fermented by lactic acid bacteria indeed has photoprotective efficacy, and the photoprotective ability can reach more than 50%.

[0074] To sum up, the present invention establishes a process for fermenting jaboticaba with an optimized formulation ratio, screening from groups such as J1-J7, and detecting the lactic acid (metabolite of lactic acid bacteria) content in the fermentation broth by HPLC, selecting the group with the highest lactic acid content, and then improving the process method according to the results of the efficacy test - there are differences between sterilized and non-sterilized jaboticaba. The extracts obtained from the fermentation of each group of J1-J7 were detected by HPLC and found that the J1 formula is the most suitable environment for the growth of lactic acid bacteria. After subsequent experiments, it was found that in the antioxidant test, in vitro and cellular tyrosinase inhibition, the efficacy of the J1-2 group was better than that of the J1-1 group, confirming that the jaboticaba can be effectively improved in antioxidant and whitening efficacy by being sterilized at high temperature and high pressure together with the culture medium before fermentation. In the comparison of the fermentation groups (J1-1, J1-2) with the non-inoculated bacteria groups (J1-1N, J1-2N) and the blank group (J1-2C), it can be found that the DPPH free radical scavenging ability, total reducing ability, in vitro and cellular tyrosinase inhibition effects of jaboticaba will increase due to the fermentation metabolism of Lactobacillus plantarum (BCRC10069), proving its unexpected efficacy after fermentation; the comparison with the J1-2C group can also prove that the source of the efficacy does not come from the culture medium, and the purpose of adding the culture medium is only to assist the growth of Lactobacillus plantarum.

[0075] To sum up, the experimental results confirm that the jaboticaba extract fermented by lactic acid bacteria obtained under specific preparation conditions has better antioxidant, whitening efficacy and photoprotective ability, and its efficacy can be greatly improved, and it can be used in the application of cosmetics or skin care products for antioxidant, repair, whitening and photoprotection.

[0076] Those skilled in the art to which the present invention pertains can understand from the foregoing that the present invention can be implemented in other specific forms of embodiments without changing the technical concept or essential features of the present disclosure. In this regard, the exemplary embodiments disclosed herein are for illustrative purposes only and should not be construed as limiting the scope of the present disclosure. On the contrary, the present disclosure is intended to cover not only the said exemplary embodiments, but also various modifications, equivalents, and other embodiments that may be included within the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A jaboticaba extract fermented by lactic acid bacteria, characterized in that, the jaboticaba extract is obtained by extracting from the product fermented by Lactobacillus plantarum with BCRC number 10069, and the preparation method of the jaboticaba extract includes: Based on the total weight of Lactobacillus plantarum and MRS broth medium, Lactobacillus plantarum is cultured in 5.5 wt% MRS broth medium at 35 °C and 50 - 150 rpm for 18 - 24 hours as the inoculum; Based on the total weight of MRS broth medium, water and jaboticaba, 2.5 wt% MRS broth medium and 67.5 wt% water are sterilized, then 30 wt% jaboticaba is added, and 5 wt% of the inoculum bacterial solution is added, and fermented at 35 °C and 150 rpm for 24 hours to obtain the jaboticaba ferment; and the supernatant obtained after centrifuging the jaboticaba ferment with a high-speed centrifuge at 1300 - 3600 rpm for 15 - 40 minutes is the jaboticaba extract, where the jaboticaba is sterilized before adding the inoculum bacterial solution.

2. The jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, When the DPPH free radical scavenging ability of the jaboticaba extract reaches IC 50 , the usage concentration of the jaboticaba extract is 1.56 wt%.

3. The jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, the total phenol content of the jaboticaba extract relative to gallic acid is 1.6 mg GAE / g.

4. The jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, The jaboticaba extract inhibits the tyrosinase activity in vitro to reach IC 50 When it reaches this point, the usage concentration of the jaboticaba extract is 3.99 wt%.

5. The jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, When the jaboticaba extract inhibits the tyrosinase activity in cells to reach IC 50 The concentration of the jaboticaba extract used is 0.31 wt%.

6. The jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, when the jaboticaba extract is diluted to 2.5 wt% and used on Hs68 cells, the survival rate of the Hs68 cells is greater than 80%.

7. The jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, when the jaboticaba extract is diluted to 2.5 wt% and used on Hs68 cells and irradiated with UV, its photoprotective ability is greater than 62%.

8. A preparation method of the jaboticaba extract fermented by lactic acid bacteria according to claim 1, characterized in that, the preparation method includes: Based on the total weight of Lactobacillus plantarum and MRS broth medium, Lactobacillus plantarum is cultured in 5.5 wt% MRS broth medium at 35 °C and 50 - 150 rpm for 18 - 24 hours as the inoculum; Based on the total weight of MRS broth medium, water and jaboticaba, after sterilizing 2.5 wt% of MRS broth medium and 67.5 wt% of water, 30 wt% of jaboticaba is added, and 5 wt% of the bacterial liquid of this kind of bacteria is added, and fermented at 35 °C and 150 rpm for 24 hours to obtain a jaboticaba ferment; and after centrifuging the jaboticaba ferment with a high-speed centrifuge at 1300 - 3600 rpm for 15 - 40 minutes, the obtained supernatant is the jaboticaba extract, where the jaboticaba is sterilized before adding the bacterial liquid of this kind of bacteria.

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