Preparation method and application of mixed fruit vesicles

Abstract

The invention belongs to the field of food, and provides a preparation method of mixed fruit vesicles, which comprises the following steps: respectively extracting phenolic compounds in grape pomace, fig pomace and hawthorn pomace to obtain a grape pomace extract, a fig pomace extract and a hawthorn pomace extract; taking at least one of the grape pomace extract, the fig pomace extract and the hawthorn pomace extract to obtain a mixed pomace extract; uniformly mixing the mixed pomace extract with soybean lecithin and water, adding gelatin and / or resistant dextrin, uniformly mixing, and performing ultrasonic treatment to obtain the vesicles. According to the invention, the grape extract, the figs, the hawthorn fruits and the nano-vesicles are organically combined for the first time. The preparation can be easily added into food and beverages, the value chain of fruits such as grapes can be enriched, and the environment and human health can be improved. The invention demonstrates that the preparation, as a novel delivery system, plays a positive role in protecting intestinal tracts and strengthening intestinal microbiomasses.

Description

Technical Field

[0001] The invention belongs to the field of food, and particularly relates to a green, economical and efficient innovative delivery system for converting grape by-products, figs and hawthorns into intestinal protection and intestinal microbial flora strengthening products. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] The winemaking process produces a large amount of grape pomace consisting of grape skins, grape seeds, and grape stems, which accounts for about 60% of the total solid waste of the winery. If the winery directly discards it as waste, it will cause certain environmental impacts.

[0004] Figs are very easy to oxidize and deteriorate and are difficult to preserve. In addition to being eaten fresh, most of them are used in the fig processing industry to produce fig juice, fig drink, fig wine, etc. Fig processing waste accounts for one-third of the total output, which is a huge amount, resulting in a waste of resources and pollution to the environment.

[0005] Hawthorn is a popular healthy food rich in vitamin C and fiber. However, a large amount of pomace is produced during the picking and processing of hawthorn every year. Directly discarding this pomace not only wastes resources, but also may cause environmental pollution.

[0006] Therefore, it is urgent to find high-value utilization methods for pomace to reduce resource waste and protect the environment. Summary of the invention

[0007] In order to solve the above problems, the present invention provides a green, economical and efficient innovative delivery system for synergistically converting grape by-products with fruits such as figs and hawthorns into intestinal protection and strengthening of intestinal microbiota.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] The first aspect of the present invention provides a method for preparing a mixed fruit vesicle, comprising:

[0010] Extracting phenolic compounds from grape pomace, fig pomace and hawthorn pomace respectively to obtain grape pomace extract, fig pomace extract and hawthorn pomace extract;

[0011] Taking at least one of the grape pomace extract, fig pomace extract and hawthorn pomace extract to obtain a mixed pomace extract;

[0012] The mixed pomace extract is mixed evenly with soybean lecithin and water, and then gelatin and resistant dextrin are added, mixed evenly, and ultrasonicated to obtain vesicles.

[0013] Research has found that grape pomace, fig pomace, and hawthorn pomace contain polyphenols such as quercetin and gallic acid. The polyphenols extracted by encapsulating phospholipid vesicles enriched by gelatin or maltodextrin or a combination of the two can effectively establish a new delivery system for the purpose of scavenging free radicals and protecting intestinal cells. Based on this, the present invention provides a delivery system specially established by vesicle-encapsulated mixed pomace extracts for protecting intestinal cells and strengthening intestinal microbiota.

[0014] In some embodiments, the extraction uses an alcohol dissolution method to extract polyphenols in the pomace, namely: an extraction ratio of 1:4-6, a temperature of 72-75° C., a time of 10-12 h, 3-4 extractions, and an ethanol content of 75-78%.

[0015] In some embodiments, the mass ratio of the mixed pomace extract to soybean lecithin is 1:6-8.

[0016] In some embodiments, the concentration of the mixed pomace extract is 40-60 mg / mL.

[0017] In some embodiments, the mass ratio of gelatin to resistant dextrin is 1:5-8.

[0018] In some embodiments, the gelatin has a concentration of 10-15 mg / mL.

[0019] In some embodiments, the concentration of the resistant dextrin is 50-60 mg / mL.

[0020] In some embodiments, the ultrasonic treatment time is 30-40 seconds, preferably, specifically: on for 5-7 seconds, off for 2-3 seconds, and multiple cycles.

[0021] In some embodiments, the power of the ultrasound is 150-200W.

[0022] The second aspect of the present invention provides a method for preparing the extract mixed fruit vesicles prepared by the above method.

[0023] The third aspect of the present invention provides the use of the method for preparing the above-mentioned extract mixed fruit vesicles in preparing drugs for intestinal protection and strengthening intestinal microflora.

[0024] Beneficial effects of the present invention

[0025] (1) The present invention utilizes vesicles to load mixed fruit and vegetable extracts, which not only has a high encapsulation rate and antioxidant activity. At the same time, the test results show that loading mixed fruit pomace extracts in vesicles is safe, can effectively protect intestinal cells from damage and death caused by oxidative stress, and also has a certain promoting effect on biofilm growth.

[0026] (2) The vesicle dispersion of the present invention is applicable to a variety of fruit pomace extracts, and has high industrial promotion value. Among them, the encapsulation effect of the mixed pomace extract composed of grape pomace, fig pomace, and hawthorn pomace is better than that of a single pomace extract, and the safety is also better.

[0027] (3) The preparation method of the present invention is simple, practical and easy to promote. DETAILED DESCRIPTION

[0028] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0029] The present invention will be further described in detail below in conjunction with specific embodiments. It should be noted that the specific embodiments are intended to explain the present invention rather than to limit it.

[0030] Example 1

[0031] (1) The polyphenols in grape pomace, fig pomace and hawthorn pomace were extracted by alcohol dissolution method, wherein the extraction ratio was 1:6, the temperature was 72°C, the time was 10 h, the extraction was repeated 3 times and the ethanol content was 78%, thereby obtaining grape pomace extract, fig pomace extract and hawthorn pomace extract.

[0032] (2) Grape pomace extract, fig pomace extract, and hawthorn pomace extract were mixed in a mass ratio of 1:1:1 to obtain a mixed pomace extract. The mixed pomace extract was mixed with soybean lecithin in a mass ratio of 1:6 and hydrated with 1 mL of water to obtain a mixed pomace extract solution (40 mg / mL). Gelatin (10 mg / mL) and FM06 (resistant dextrin) (50 mg / mL) was simultaneously added to the mixed pomace extract solution (the ratio of mixed pomace extract solution to gelatin and resistant dextrin was 4:1:5) to obtain an aqueous dispersion. All aqueous dispersions were sonicated using a Soniprep 150 ultrasonic disintegrator (5 seconds on, 2 seconds off, 3 cycles, allowing the sample to cool between each ultrasonic step) to obtain a uniform vesicle dispersion.

[0033] (3) The samples were diluted with water (1:100) and analyzed at 25°C. Each vesicle dispersion (2 mL) was dialyzed, and the water was changed every hour. After 48 h of dialysis, vesicles loaded with mixed pomace extracts were obtained. The antioxidant activity (DPPH) of the samples was measured, and the encapsulation efficiency was calculated.

[0034] (4) Caco-2 cell monolayers grown on 75-cm 2 The cells were cultured in Dulbecco's Modified Eagle Me-dium (DMEM) containing glucose, 10% fetal bovine serum, and 1% penicillin / streptomycin in flasks at 37°C with 100% humidity and 5% CO2. Cell viability was determined using the MTT assay. Cells (7.5×10 cells / well) were plated and incubated at 4 °C with 1% CO2. 3 ) were inoculated into 96-well plates. After 24 h, 25 μl of the sample (vesicles loaded with mixed pomace extracts), previously diluted to the desired concentration (4 μg / mL), was applied to the cells. After 48 h of incubation, MTT solution (0.5 mg / mL, final concentration) was added to each well, removed after 3 h and replaced with dimethyl sulfoxide. The absorbance of the dissolved dye was measured at 570 nm using a microplate reader. The percentage survival of the treated cells compared to the untreated control cells (100% cell survival) was calculated.

[0035] (5) Use Lactobacillus reuteri. Before use, the probiotics in the exponential growth phase were stored in plastic tubes containing 20% ​​glycerol and brain heart infusion (BHI) broth of Lactobacillus reuteri at -80°C. A 96-well microplate containing a dilution (250 μg / mL) of the sample (vesicles loaded with mixed pomace extract) and the selected bacterial strains were incubated at 37°C for 6 days to form a microbial biofilm. The plate samples were washed with PBS solution to eliminate eosinophils, and then the biofilm was stained with 100 μl of crystal violet solution at 25°C for 10 minutes. After washing three times with PBS solution, 200 μl of acetic acid solution (30% v / v) was added to each well to dissolve the dye from the bacterial biomass. Biofilm growth was measured at 620 nm using a microplate reader spectrophotometer.

[0036] Example 2

[0037] The difference from Example 1 is that grape pomace extract is used instead of mixed pomace extract.

[0038] Example 3

[0039] The difference from Example 1 is that the mixed pomace extract is replaced by the fig pomace extract.

[0040] Example 4

[0041] The difference from Example 1 is that hawthorn residue extract is used instead of mixed pomace extract.

[0042] Table 1 Performance test data of vesicles

[0043]

[0044] As shown in Table 1, it is because the resistant dextrin and the residual fiber can interact with the polyphenols in the extract in a non-covalent manner. This binding process starts from the fiber surface and continues to diffuse into the fiber, thereby improving the binding of the polyphenols contained in the extract with the dextrin dissolved in the vesicle water chamber, so that the vesicle embedding rate can reach 62%-88%, greatly improving the encapsulation degree of the extract, and thus improving the efficiency of the vesicle. The encapsulation effect of the mixed pomace extract composed of grape pomace, fig pomace, and hawthorn pomace is better than that of a single pomace extract, and the antioxidant activity is also slightly enhanced.

[0045] Table 2 Effect on strain survival rate

[0046] sample Survival rate (%) Example 1 97％-100％ Example 2 79％-86％ Example 3 71％-78％ Example 4 76％-81％

[0047] Caco-2 cells were incubated with samples of different dilutions for 48 hours and reacted to 4 μg / mL of extracts. As shown in Table 2, loading the mixed pomace extracts in the vesicles can better improve cell viability, up to 100%, and the stimulation effect on cell growth is more obvious. It is confirmed that loading the extracts in the vesicles is safe.

[0048] Table 3 Effects on the biofilm growth of strains

[0049] sample Survival rate (%) Example 1 88％-93％ Example 2 64％-73％ Example 3 66％-70％ Example 4 63％-72％

[0050] The effects of mixed fruit extracts on Lactobacillus reuteri and Streptococcus salivarius biofilms showed that at higher concentrations (250 μg / mL), vesicles loaded with mixed fruit extracts had a better stimulatory effect on the selected biofilms. In particular, gelatin-enriched vesicles stimulated the proliferation of Lactobacillus reuteri to a greater extent.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing mixed fruit vesicles, characterized in that: include: Extracting phenolic compounds from grape pomace, fig pomace and hawthorn pomace respectively to obtain grape pomace extract, fig pomace extract and hawthorn pomace extract; Taking at least one of the grape pomace extract, fig pomace extract and hawthorn pomace extract to obtain a mixed pomace extract; The mixed pomace extract is mixed evenly with soybean lecithin and water, and then gelatin and / or resistant dextrin are added, mixed evenly, and ultrasonicated to obtain vesicles.

2. The method for preparing the mixed fruit vesicle according to claim 1, wherein The mass ratio of the mixed pomace extract to soybean lecithin is 1:6-8.

3. The preparation method of the mixed fruit vesicle as claimed in claim 1, characterized in that, The concentration of the mixed fruit extract is 40-60 mg / mL.

4. The method for preparing the mixed fruit vesicle according to claim 1, wherein The mass ratio of the gelatin to the resistant dextrin is 1:5-8.

5. The method for preparing the mixed fruit vesicle according to claim 1, characterized in that, The concentration of the gelatin is 10-15 mg / mL.

6. The method for preparing the mixed fruit vesicle according to claim 1, characterized in that: The concentration of the resistant dextrin is 50-60 mg / mL.

7. The method for preparing the mixed fruit vesicle according to claim 1, characterized in that: The ultrasonic treatment time is 30-40 seconds, preferably, specifically: on for 5-7 seconds, off for 2-3 seconds, and multiple cycles.

8. The method for preparing the mixed fruit vesicle according to claim 1, characterized in that: The power of the ultrasound is 150-200W.

9. A method for preparing the mixed fruit vesicles prepared by the method described in any one of claims 1 to 8.

10. Use of the preparation method of the mixed fruit vesicles according to claim 9 in preparing drugs for intestinal protection and strengthening of intestinal microflora.

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