Fermented vegetable oil soluble compound and preparation method thereof

Abstract

The invention belongs to the field of vegetable oil chemical modification, and discloses a fermented vegetable oil oil-soluble compound and a preparation method thereof.The fermented vegetable oil oil-soluble compound is prepared from linseed oil or castor oil rich in omega-3 fatty acid and epoxy fatty acid through ultrasonic and microwave coupling pretreatment by means of the synergistic effect of the ultrasonic cavitation effect and the microwave heat effect; performing ultrasonic and microwave alternate treatment to remarkably enhance the release efficiency of fatty acid in the oil and destroy the oil phase matrix structure; inoculating the modified oil material, a molybdenum disulfide precursor and oil-resistant microorganisms into a culture medium, and fermenting to realize low-temperature in-situ mineralization embedding; and carrying out high-shear emulsification on the fermentation supernatant and vegetable oil in a mass ratio of 1: 1 to prepare the oil-soluble compound with excellent dispersion stability and functional performance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of chemical modification of vegetable oil, and particularly relates to a fermented vegetable oil oil-soluble complex and a preparation method thereof. BACKGROUND

[0002] Vegetable oil is rich in omega-3 polyunsaturated fatty acids and epoxy fatty acids, and has important application value in medicine, cosmetics, functional food and high-end lubricant additives. However, it is difficult to achieve uniform dispersion and long-term stability in the oil phase due to its strong hydrophobicity and complex structure. Although existing cyclodextrin inclusion, liposome, polymer micelle and chemical co-precipitation technologies can improve the dispersibility, the poor compatibility between the carrier and the oil phase, the complex preparation process, the sensitivity to temperature and pH, and the need for high temperature and long time and organic solvents result in insufficient product stability, poor greenness and high cost. Metal nanoparticles and MoS2 quantum dots have excellent electrical, optical and antibacterial properties and are considered as ideal functional enhancers. However, traditional chemical reduction, high-temperature pyrolysis or physical deposition synthesis conditions are harsh, and cannot realize in-situ synergistic compounding in the oil phase under mild conditions. The coupling pretreatment technology of ultrasonic cavitation and microwave heating has obvious advantages in structure reconstruction and energy transfer, but is mainly used in aqueous or solid phases, and has not been combined with microbial in-situ mineralization technology and applied in oil phase systems. Although microbial in-situ mineralization can generate nanoparticles at low temperature in the extracellular environment, it is mainly limited to the fields of water treatment and mineral synthesis, and there is no mature process in the preparation of oil phase composite materials. SUMMARY

[0003] To solve the problems mentioned in the background, the present application provides a fermented vegetable oil oil-soluble complex and a preparation method thereof. The vegetable oil modification method of ultrasonic-microwave coupling pretreatment and grafting 3-mercaptopropyl trimethoxysilane is combined with microbial extracellular ammonium tetrathiomolybdate in-situ mineralization to generate MoS2 quantum dots, so as to realize deep covalent compounding of nanoparticles and functional fatty acids.

[0004] The object of the present application can be achieved by the following technical solutions:

[0005] A fermented vegetable oil oil-soluble complex, comprising the following raw materials in parts by weight: vegetable oil raw material 5-20 parts, modified oil 5-20 parts, molybdenum disulfide quantum dots 0.01-0.5 parts, oil-soluble surfactant 2-10 parts, natural antioxidant 1-3 parts, and clay mineral nanosheet 1-4 parts.

[0006] The molybdenum disulfide quantum dots are generated by microbial in-situ mineralization.

[0007] Further preferably, the preparation method of the modified oil comprises the following steps:

[0008] A. Mix the plant oil raw material rich in omega-3 fatty acids and epoxy fatty acids with an oil-soluble surfactant, and protect it with nitrogen, then add 3-mercapto propyl trimethoxysilane to the premix, and mix well;

[0009] B. Under constant temperature conditions, the mixed solution of step A is subjected to 30 min ultrasonic cavitation oscillation treatment to destroy the oil phase matrix and initiate methoxy hydrolysis;

[0010] C. The ultrasonic treated system is transferred to a microwave reactor, and the oil phase molecules are induced to aggregate and rearrange by the microwave electromagnetic field, realizing the secondary dispersion and structure reconstruction inside the oil droplets, and obtaining modified oil material with micro-pore structure and high surface area.

[0011] Further preferably, the oil-soluble surfactant is one or more of octylphenol polyoxyethylene ether, polysorbate 80 and alkyl succinimide.

[0012] Further preferably, the conditions of ultrasonic and microwave coupling pretreatment in steps B and C are: 300 W ultrasonic treatment for 30 min; followed by 500 W microwave treatment for 5 min.

[0013] A preparation method of a fermented plant oil oil-soluble complex, comprising the following steps:

[0014] S1. Mix the plant oil raw material with an oil-soluble surfactant and perform ultrasonic and microwave coupling pretreatment to obtain modified oil material;

[0015] S2. Inoculate the modified oil material with ammonium tetrathiomolybdate and oil-tolerant microorganisms into a culture medium and ferment to realize in-situ mineralization of molybdenum disulfide quantum dots;

[0016] S3. Centrifuge the fermentation broth to obtain supernatant;

[0017] S4. High-shear emulsify the supernatant and plant oil at a mass ratio of 1:1 to obtain a fermented plant oil oil-soluble complex.

[0018] Further preferably, the oil-tolerant microorganism is genetically modified Bacillus subtilis.

[0019] Further preferably, the preparation raw material further comprises 1-5 parts of an antioxidant synergist, which is one or more of vitamin E, natural phenols and esterified derivatives thereof.

[0020] Further preferably, after step S4, an antioxidant synergist is further added and high-shear emulsified with the separated supernatant and plant oil to obtain a fermented plant oil oil-soluble complex containing a synergistic antioxidant.

[0021] The beneficial effects of the present application are:

[0022] The original plant oil molecular skeleton is effectively cracked and restructured by the synergistic effect of ultrasonic-microwave coupling pretreatment and covalent grafting of 3-mercaptopropyl trimethoxysilane, to generate modified oil with micro-pore structure and large specific surface area, thereby significantly improving the release rate of omega-3 polyunsaturated fatty acids and epoxy fatty acids in the oil phase. In the subsequent microbial fermentation process, the extracellular enzyme system of oil-tolerant strains is used to in-situ mineralize ammonium tetrathiomolybdate into MoS2 quantum dots, so that the nanoparticles are uniformly and long-acting dispersed in the oil phase and deeply fused with active fatty acids, completely avoiding the phase separation and inactivation of active ingredients that easily occur in the traditional emulsion system. The obtained composite presents a new absorption characteristic peak in the ultraviolet-visible light region, proving its potential in the field of photoelectric conversion; the conductivity is more than 50% higher than that of unmodified materials, showing excellent conductive performance; at the same time, the surface thiol and siloxane functional groups provide broad-spectrum antibacterial activity, which has significant inhibitory effect on gram-positive and negative bacteria. BRIEF DESCRIPTION OF DRAWINGS

[0023] The application will be further described below with reference to the drawings.

[0024] Figure 1 The functional fatty acid release rate comparison chart of the fermented plant oil oil-soluble complex prepared for examples 1-3 and comparative examples 1-2;

[0025] Figure 2 The viscosity recovery rate and loss rate comparison chart of the fermented plant oil oil-soluble complex prepared for examples 1-3 and comparative examples 1-2. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the application will be described below in a clear and complete manner with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0027] Example 1

[0028] I. Preparation of modified oil

[0029] Take 100 g of flaxseed oil, add 5 g of polysorbate-80 and 2 g of 3-mercapto propyl trimethoxysilane into a 500 mL stoppered reaction bottle, slowly pass nitrogen at a flow rate of 0.2 L / min for 5 min, then place the reaction bottle in an ultrasonic cleaner, set the power to 300 W and the constant temperature to 40 ℃, and perform 30 min cavitation oscillation on the pre-mixture to break the oil droplet matrix and initiate the hydrolysis grafting reaction of the methoxy group of 3-mercapto propyl trimethoxysilane. Move the ultrasonic treatment liquid into a microwave reactor, irradiate with a microwave at a power of 500 W for 5 min, and the system temperature rises to 60~70 ℃, the microwave electromagnetic field promotes the molecular rearrangement and secondary dispersion in the oil droplets, forming modified oil with fine pore structure and high specific surface area.

[0030] II. Preparation of fermented vegetable oil oil-soluble complex

[0031] The fermented vegetable oil oil-soluble complex comprises the following raw materials by weight: vegetable oil raw material 5 parts, modified oil 5 parts, molybdenum disulfide quantum dots 0.01 parts, oil-soluble surfactant 2 parts, natural antioxidant 1 part, clay mineral nanosheet 1 part;

[0032] The preparation method is as follows: prepare liquid LB medium according to the formula of 10 g / L tryptone, 5 g / L yeast extract, 10 g / L NaCl, adjust the pH to 7.0, sterilize at 121 ℃ for 15 min, and then cool to 25 ℃ for standby. Take the oil-tolerant Bacillus subtilis frozen strain and inoculate it into 5 mL of LB liquid medium, and incubate it at 37 ℃ with shaking for 8 h to obtain logarithmic growth phase bacterial liquid with OD600≈1.0. Take 100 mL of sterile LB medium, add 5 g of modified oil, 0.01 g of ammonium tetrathiomolybdate, and 50 μL of Tween 80 as a solubilizer, and supplement 10% deep eutectic solvent (choline chloride: citric acid 1:2) to enhance substrate dissolution; pass sterile air for 5 min and mix evenly; inoculate 1 mL of activated bacterial liquid, and shake at 30 ℃ and 150 rpm for 24 h; take samples every 4 h to measure pH, dissolved oxygen and OD600, and ensure that the dissolved oxygen is maintained above 20%; after fermentation, centrifuge at 4000 rpm for 15 min and discard the bacterial bodies; precipitate the impurities in the supernatant with an equal volume of anhydrous ethanol, and centrifuge again at 4000 rpm for 10 min to collect the ultra-pure supernatant. Place the supernatant, 5 g of fresh vegetable oil, 2 g of polysorbate-80, 1 g of rosemary acid, and 1 g of clay mineral nanosheet in a 600 mL double-layer emulsification tank; initially stir at 1000 rpm for 2 min to remove air bubbles; gradually increase the shear to 8000 rpm for 2 min, and then to 12000 rpm for 3 min; control the temperature within 40 ℃, and perform vacuum degassing for 10 min after emulsification to obtain the fermented vegetable oil oil-soluble complex.

[0033] Example 2

[0034] The preparation of the modified oil was the same as in Example 1.

[0035] The preparation process of the fermented vegetable oil oil-soluble complex is as follows:

[0036] The fermented vegetable oil oil-soluble complex comprises the following raw materials in parts by weight: 20 parts vegetable oil raw material, 20 parts modified oil, 0.5 parts molybdenum disulfide quantum dots, 10 parts oil-soluble surfactant, 3 parts natural antioxidant, and 4 parts clay mineral nanosheets.

[0037] The preparation steps are as follows: Logarithmic growth phase bacterial culture was obtained according to Example 1, and OD600≈1.0 was measured. 100 mL of sterile LB medium was taken, and 20 g of modified oil, 0.5 g of ammonium tetrathiomolybdate, and 50 μL of Tween 80 co-solvent were added. 10% deep eutectic solvent (choline chloride:citric acid 1:2) was added to enhance substrate solubility. Sterile air was introduced for 5 min, and the mixture was stirred thoroughly. 1 mL of activated bacterial culture was inoculated, and fermentation was carried out at 30℃ and 150 rpm for 24 h with shaking. Samples were taken every 4 h to measure pH, dissolved oxygen, and OD600, ensuring that dissolved oxygen was maintained above 20%. After fermentation, the culture was centrifuged at 4000 rpm for 15 min, and the bacterial cells were discarded. The supernatant was pre-cooled with an equal volume of anhydrous ethanol to precipitate impurities, and then centrifuged again at 4000 rpm for 10 min to collect the ultrapure supernatant. The supernatant was placed in a 600 mL double-walled emulsifying tank with 20 g of fresh vegetable oil, 10 g of polysorbate-80, 3 g of rosmarinic acid, and 4 g of clay mineral nanosheets. The mixture was initially stirred at 500 rpm for 3 min to remove large air bubbles. The stirring was then gradually increased to 12,000 rpm and sheared for 2 min, followed by another 3 min at 12,000 rpm. The temperature was controlled below 45°C. After emulsification, the mixture was degassed under vacuum for 10 min to obtain the fermented vegetable oil oil-soluble complex.

[0038] Example 3

[0039] The preparation of the modified oil was the same as in Example 1.

[0040] The preparation process of the fermented vegetable oil oil-soluble complex is as follows:

[0041] The fermented vegetable oil oil-soluble complex comprises the following raw materials in parts by weight: 12.5 parts vegetable oil raw material, 12.5 parts modified oil, 0.255 parts molybdenum disulfide quantum dots, 6 parts oil-soluble surfactant, 2 parts natural antioxidant, and 2.5 parts clay mineral nanosheets.

[0042] The preparation steps are as follows: the logarithmic growth phase bacterial solution is obtained according to Example 1, and the OD600 is measured to be about 1.0. 100 mL of sterile LB medium is taken, 12.5 g of modified oil, 0.255 g of ammonium tetrathiomolybdate, 50 μL of Tween 80 cosolvent, and 10% deep eutectic solvent are added; sterile air is introduced for 5 min, and stirring is uniform; 1 mL of activated bacterial solution is inoculated, and fermentation is carried out at 30°C, 150 rpm for 24 h; sampling is performed every 4 h, and pH, dissolved oxygen and OD600 are measured to ensure that the dissolved oxygen is maintained above 20%; after fermentation, centrifugation is performed at 4000 rpm for 15 min, and the bacterial bodies are discarded; the supernatant is pre-cooled and precipitated with an equal volume of anhydrous ethanol to remove impurities, and centrifugation is performed again at 4000 rpm for 10 min to collect the ultra-pure supernatant. The supernatant is placed in a 600 mL double-layer emulsification tank together with 12.5 g of fresh vegetable oil, 6 g of polysorbate-80, and 2 g of rosemary acid and 2.5 g of clay mineral nanosheets; the stirring speed is increased to 8000 rpm for 3 min, and then to 12000 rpm for 2 min, and the tank temperature is maintained at ≤40°C throughout the process; after emulsification, vacuum degassing is performed for 10 min to obtain the fermented vegetable oil oil-soluble complex.

[0043] Comparative Example 1 (silane grafting is omitted)

[0044] I. Preparation of modified oil

[0045] 100 g of linseed oil is weighed, 5 g of polysorbate-80 is added, and the mixture is poured into a 500 mL reaction bottle with a stopper. Nitrogen is slowly introduced at a flow rate of 0.2 L / min for 5 min, and then the reaction bottle is placed in an ultrasonic cleaner, set to a power of 300 W and a constant temperature of 40°C, and the pre-mixture is subjected to 30 min of cavitation oscillation. The ultrasonic treatment liquid is transferred to a microwave reactor, and irradiated with microwaves at a power of 500 W for 5 min, and the system temperature rises to 60-70°C, forming a modified oil with a micro-porous structure and high specific surface area.

[0046] The fermented vegetable oil oil-soluble complex comprises the following raw materials by weight: 12.5 parts of vegetable oil, 12.5 parts of modified oil, 0.255 parts of molybdenum disulfide quantum dots, 6 parts of oil-soluble surfactant, 2 parts of natural antioxidant, and 2.5 parts of clay mineral nanosheets;

[0047] The preparation steps are as follows: the logarithmic growth phase bacterial solution is obtained according to Example 1, and the OD600 is measured to be about 1.0. 100 mL of sterile LB medium is taken, 12.5 g of modified oil, 0.255 g of ammonium tetrathiomolybdate, 50 μL of Tween 80 cosolvent, and 10% deep eutectic solvent are added; sterile air is introduced for 5 min, and stirring is uniform; 1 mL of activated bacterial solution is inoculated, and fermentation is carried out at 30℃ with 150 rpm shaking for 24 h; sampling is performed every 4 h to measure pH, dissolved oxygen and OD600, and the dissolved oxygen is maintained above 20%; after fermentation, centrifugation is performed at 4000 rpm for 15 min, and the bacterial bodies are discarded; the supernatant is pre-cooled with an equal volume of anhydrous ethanol to precipitate impurities, and centrifugation is performed again at 4000 rpm for 10 min to collect the ultra-pure supernatant. The supernatant is placed in a 600 mL double-layer emulsification tank together with 12.5 g of fresh vegetable oil, 6 g of polysorbate-80, and 2 g of rosemary acid and 2.5 g of clay mineral nanosheets; the stirring speed is increased to 8000 rpm for 3 min, and then to 12000 rpm for 2 min, and the tank temperature is maintained at ≤40℃ throughout the process; after emulsification, vacuum degassing is performed for 10 min, and the fermented vegetable oil oil-soluble complex is obtained.

[0048] Comparative Example 2 (chemical reduction method instead of microbial in-situ mineralization)

[0049] The modified oil is prepared according to Example 1.

[0050] The preparation process of the fermented vegetable oil oil-soluble complex is as follows:

[0051] The fermented vegetable oil oil-soluble complex comprises the following raw materials by weight: 12.5 parts of vegetable oil raw material, 12.5 parts of modified oil, 0.255 parts of molybdenum disulfide nanoparticles obtained by chemical reduction method, 6 parts of oil-soluble surfactant, 2 parts of natural antioxidant, and 2.5 parts of clay mineral nanosheets;

[0052] The preparation steps are as follows: the logarithmic growth phase bacterial solution is obtained according to Example 1, and the OD600 is measured to be about 1.0. 100 mL of sterile LB medium is taken, 12.5 g of modified oil is added, 0.255 g of molybdenum disulfide nanoparticles, 50 μL of Tween 80 cosolvent, and 10% deep eutectic solvent is supplemented; sterile air is introduced for 5 min, and stirring is uniform; 1 mL of activated bacterial solution is inoculated, and fermentation is carried out at 30°C, 150 rpm for 24 h; sampling is carried out every 4 h, and pH, dissolved oxygen and OD600 are measured to ensure that the dissolved oxygen is maintained above 20%; after fermentation, centrifugation is carried out at 4000 rpm for 15 min, and the bacterial bodies are discarded; the supernatant is pre-cooled and precipitated with an equal volume of anhydrous ethanol to remove impurities, and centrifugation is carried out again at 4000 rpm for 10 min, and the ultra-pure supernatant is collected. The supernatant is placed in a 600 mL double-layer emulsification tank together with 12.5 g of fresh vegetable oil, 6 g of polysorbate-80, and 2 g of rosemary acid, 2.5 g of clay mineral nanoparticle; primary stirring is carried out at 500 rpm for 3 min to remove large air bubbles, and the shear is increased to 8000 rpm for 3 min, and then to 12000 rpm for 2 min, and the tank temperature is maintained at ≤40°C throughout the process, and vacuum degassing is carried out for 10 min after emulsification, and the fermented vegetable oil oil-soluble compound is obtained.

[0053] Performance detection

[0054] 1. Functional fatty acid release rate determination

[0055] The lipid components are extracted from the oil phase with n-hexane, and methyl esterification is carried out at 60°C with 2% methanol sulfuric acid solution to convert free fatty acids into fatty acid methyl esters. After treatment, the upper methyl ester phase is blown to constant volume with anhydrous nitrogen gas, and used as a GC-MS sample. The chromatography uses a DB-5MS capillary column, the temperature program starts at 80°C and rises to 300°C, the carrier gas is helium at a flow rate of 1.0 mL / min, the sample size is 1 μL (split ratio 10:1), and the mass spectrometry ionization uses a 70 eV electron bombardment mode. The external standard curve is drawn using standard products with a purity of ≥99%, and the EPA / DHA and epoxy fatty acid concentrations in the sample, i.e. the release efficiency, are calculated, and the results are shown in Table 1.

[0056] Table 1 Fatty acid release rate

[0057] Sample ω-3 release rate (%) Epoxy fatty acid release rate (%) Example 1 60.0 55.0 Example 2 80.0 75.0 Example 3 90.0 85.0 Comparative Example 1 50.0 45.0 Comparative Example 2 55.0 50.0

[0058] From Table 1, the release rates of ω-3 polyunsaturated fatty acids and epoxy fatty acids in Example 3 reached 90% and 85%, respectively, far exceeding Comparative Examples 1-2, reflecting the synergistic effect of ultrasonic-microwave coupled pretreatment combined with silane grafting and functional modification of oil materials, which maximized the release of active fatty acids. The release rate of Comparative Example 1 was only 50% and 45%, indicating that the modified oil material lacking silane functional groups was significantly insufficient in oil droplet structure stability and functional group affinity, thereby reducing the desorption efficiency of fatty acids from the matrix. The release rate of Comparative Example 2 was only 55% and 50%, indicating that the MoS2 nanoparticles synthesized by traditional chemical synthesis had a large particle size, were prone to aggregation, and had residual reducing agents on the surface, which not only failed to achieve deep integration with the active components in the oil phase, but also restricted the catalytic or surface active effect of MoS2 nanoparticles in promoting the release of fatty acids.

[0059] 2. Specific surface area and pore structure characterization test of modified oil material

[0060] The modified oil materials of different samples were placed in a sample tube and degassed at 120 °C under vacuum for 12 h to remove surface adsorbed moisture and volatiles. The adsorption-desorption isotherms of each sample were measured using a BET nitrogen adsorption-desorption instrument (77 K). The specific surface area (SSA) was calculated by fitting the BET model in the relative pressure range P / P0 = 0.05-0.30; the pore size distribution was calculated from the desorption curve using the BJH method, and the results are shown in Table 2.

[0061] Table 2. Specific surface area and pore structure characterization results of modified oil material

[0062] Sample Specific surface area SSA (m2 / g) Average pore size (nm) Example 1 60 ± 1.2 6.0 ± 0.3 Example 2 68 ± 1.5 7.8 ± 0.2 Example 3 75 ± 2.0 8.0 ± 0.4 Comparative Example 1 40 ± 1.0 4.0 ± 0.3 Comparative Example 2 55 ± 1.3 6.0 ± 0.3

[0063] As can be seen from Table 2, the specific surface area of the modified oil material of Example 3 reached 75 m² / g, and the average pore size was about 8.0 nm, far exceeding Comparative Examples 1-2, indicating that the synergistic effect of ultrasonic-microwave coupled pretreatment and covalent grafting of 3-mercaptopropyltrimethoxysilane in the present application: ultrasonic cavitation first breaks the oil droplet matrix and generates microcracks, and the subsequent microwave field induces molecular rearrangement and secondary dispersion, which builds a more connected porous network inside the oil droplet; silane grafting not only forms an organic-inorganic hybrid layer on the pore wall, but also further stabilizes the pore structure to prevent collapse. The specific surface area of Comparative Example 1 decreased to 40 m² / g due to the lack of a grafting agent, and the average pore size in Comparative Example 2 decreased to 6.0 nm due to the use of chemically synthesized MoS2 instead of in-situ mineralization of microorganisms, indicating that both have a key impact on pore formation and stability.

[0064] 3. Antibacterial activity test

[0065] Staphylococcus aureus and Escherichia coli were used as test strains, and the strains were inoculated on LB plates and incubated at 37°C for 18 h to obtain fresh single colonies. Single colonies were inoculated into 10 mL of LB liquid medium and shaken at 37°C and 200 rpm until the logarithmic growth phase. The logarithmic phase bacterial solution was diluted with physiological saline to 10 6 CFU / mL, and 100 μL of the diluted bacterial solution was spread on the surface of the MH agar plate. A 6 mm diameter hollow circle was placed at the center of the hole puncher, and 50 μL of the sample was added. Positive and negative controls (penicillin) were placed around the plate. After incubation at 37°C for 24 h, the diameter of the inhibition zone was measured.

[0066] Using the standard microdilution method, the sample concentration gradient was set to 0.125-16 mg / mL in a 96-well plate. 100 μL of the diluted bacterial solution was added to each well, and the plate was incubated at 37°C for 24 h. The growth was read using an enzyme-labeled instrument (OD 6 600 ). The lowest concentration without turbidity corresponds to the MIC. The results are shown in Table 3 below.

[0067] Table 3 Antimicrobial activity test results

[0068] Sample Staphylococcus aureus inhibition zone (mm) Escherichia coli inhibition zone (mm) MIC (mg / mL) Example 1 12.0 ± 0.5 11.0 ± 0.6 8.0 Example 2 16.0 ± 0.7 15.0 ± 0.5 4.0 Example 3 20.0 ± 0.6 19.0 ± 0.7 1.0 Comparative Example 1 10.0 ± 0.4 9.0 ± 0.5 16.0 Comparative Example 2 11.0 ± 0.5 10.0 ± 0.6 12.0

[0069] As can be seen from Table 3, the inhibition zone diameters of Example 3 on Staphylococcus aureus and Escherichia coli were 20.0 mm and 19.0 mm, respectively, and the MIC was as low as 1.0 mg / mL, which was better than other examples and comparative examples. This indicates that the ultrasonic-microwave coupling pretreatment and MPTMS functionalization grafting in Example 3 give the modified oil higher interfacial activity and structural stability. The uniform and fine MoS2 quantum dots generated by in-situ mineralization of microorganisms and the montmorillonite nanosheets synergistically enhance the dispersion and contact efficiency of nanoparticles in the oil phase, thereby significantly improving the antimicrobial performance. Comparative Example 1 lacks silane covalent grafting, and the interfacial bonding force decreases, resulting in a decrease in antimicrobial activity. Comparative Example 2 uses chemically synthesized MoS2, which has a large particle size and residual reducing agent on the surface, affecting the activity of the particles, and also has lower antimicrobial effect than the in-situ mineralized sample.

[0070] 4. Rheological and mechanical shear stability test

[0071] The prepared oil-soluble nanocomposite sample was placed in a rotational / rheometer (equipped with parallel plate geometry) with an environmental temperature of 25°C. The test procedure was as follows:

[0072] Shear viscosity curve: the viscosity was measured by logarithmic scanning within a shear rate range of 0.1-1000 s⁻¹ to obtain the rheological curve. ​

[0073] Yield stress measurement: in small deformation stress sweep mode, stress was applied step by step with 0.5 Pa increment from 0.1 Pa, the critical stress (yield stress) of the material was recorded when it turned from solid to flow state;

[0074] Recovery rate test: first destroy the structure at 100 s⁻¹ for 30 s, then measure the viscosity recovery at 1 s⁻¹ for 30 s, recovery rate = (viscosity after recovery / initial viscosity) x 100%;

[0075] High shear cycle test: the sample was subjected to 3 cycles (30 s high shear + 30 s rest per cycle) at 100 s⁻¹, the viscosity at 1 s⁻¹ before and after the test cycle was measured, the viscosity loss rate = (initial viscosity - viscosity after cycle) / initial viscosity x 100%.

[0076] The results are shown in Table 4 below.

[0077] Table 4 Rheological and mechanical shear stability results

[0078] Sample zero shear viscosity η0(Pa-s) Yield stress (Pa) Recovery rate (%) Viscosity loss rate (%) Example 1 6.5 ± 0.3 10.0 ± 0.5 70 ± 3 35 ± 2 Example 2 8.5 ± 0.4 12.0 ± 0.6 75 ± 4 30 ± 2 Example 3 12.0 ± 0.5 18.0 ± 0.8 90 ± 3 15 ± 1 Comparative Example 1 4.8 ± 0.2 7.0 ± 0.4 55 ± 4 45 ± 3 Comparative Example 2 5.2 ± 0.3 8.0 ± 0.5 65 ± 3 40 ± 2

[0079] As can be seen from Table 4, the zero shear viscosity of Example 3 reaches 12.0 Pa·s, which is higher than that of Example 1 and Example 2, and the yield stress is as high as 18.0 Pa, the recovery rate reaches 90%, and the viscosity loss rate is only 15%, indicating that the formulation can maintain excellent structural integrity and rapid self-recovery ability after low-speed static and high-shear cycle, which is due to the efficient reconstruction of the internal micropore network of the oil droplet by ultrasonic-microwave coupling pretreatment, the reinforcement of the pore wall by covalent grafting of 3-mercaptopropyltrimethoxysilane, and the synergistic support of in-situ mineralized MoS2 quantum dots and montmorillonite nanosheets. The η0, yield stress, recovery rate and shear instability of Comparative Example 1 all decreased significantly, proving the key role of covalently grafted functional groups in maintaining network connectivity and interfacial adhesion; Comparative Example 2 is slightly higher than Comparative Example 1, but still lower than Examples 1-3, showing the structural advantages brought by the deep integration of in-situ mineralized fine particles and oil phase active matrix.

[0080] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Also, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0081] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A fermented vegetable oil oil-soluble complex, characterized in that, The preparation method of the modified oil material specifically comprises the following steps: The microbial in-situ mineralization generates the molybdenum disulfide quantum dots.

2. The fermented plant oil oil-soluble complex according to claim 1, wherein, The preparation method of the modified oil material specifically comprises the following steps: A. The plant oil material rich in omega-3 fatty acids and epoxy fatty acids is mixed with an oil-soluble surfactant, and nitrogen is introduced for protection, 3-mercaptopropyl trimethoxysilane is added to the premix, and the mixture is mixed uniformly; B. The mixture of step A is subjected to ultrasonic cavitation oscillation treatment under constant temperature conditions for 30 min to destroy the oil phase matrix and start the methoxy hydrolysis; C. The ultrasonic treated system is transferred to a microwave reactor, and the oil phase molecules are induced to aggregate and rearrange by a microwave electromagnetic field to realize secondary dispersion and structure reconstruction inside the oil droplets, and the modified oil material with micro-pore structure and high surface area is obtained.

3. The fermented vegetable oil oil-soluble complex of claim 1, wherein, The oil-soluble surfactant is one or more of octylphenol polyoxyethylene ether, polysorbate 80 and alkyl succinimide.

4. The fermented, plant oil, oil-soluble complex of claim 2, wherein, The conditions of the ultrasonic and microwave coupling pretreatment in steps B and C are: 300 W ultrasonic treatment for 30 min, and then 500 W microwave treatment for 5 min.

5. A process for the preparation of a fermented vegetable oil oil-soluble complex, such as claimed in any one of claims 1 to 4, characterised in that, The method comprises the following steps: S1. The plant oil material is mixed with an oil-soluble surfactant and subjected to ultrasonic and microwave coupling pretreatment to prepare a modified oil material; S2. The modified oil material is inoculated with ammonium tetrathiomolybdate and oil-resistant microorganisms in a culture medium and fermented to realize in-situ mineralization of molybdenum disulfide quantum dots; S3. The fermentation broth is subjected to centrifugal separation to obtain a supernatant; S4. The supernatant and the plant oil are subjected to high-shear emulsification at a mass ratio of 1:1 to obtain a fermented plant oil oil-soluble compound.

6. The method for preparing the fermented vegetable oil oil-soluble complex according to claim 5, characterized in that, The oil-resistant microorganism is genetically modified Bacillus subtilis.

7. The fermented vegetable oil oil-soluble complex of claim 1, wherein, The preparation raw material further comprises an antioxidant synergist 1-5 parts, and the antioxidant synergist is one or more of vitamin E, natural phenols and esterified derivatives thereof.

8. The method for preparing the fermented vegetable oil oil-soluble complex according to claim 6, characterized in that, After step S4, the antioxidant synergist is further added and subjected to high-shear emulsification with the separated supernatant and the plant oil to obtain a fermented plant oil oil-soluble compound containing a synergistic antioxidant.

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