Lutein and flaxseed oil self-emulsifying soft capsules and preparation method thereof

Abstract

The application discloses a lutein and flaxseed oil self-emulsifying soft capsule and a preparation method thereof, relates to the technical field of microcapsule preparations, and comprises an oil phase compartment and a dry powder compartment which are separated in the capsule shell. The oil phase compartment contains camellia seed oil, perilla seed oil, flaxseed oil, MCT (medium-chain triglyceride), DHA algal oil, astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, an emulsifier, mixed natural tocopherol and oil-soluble rosemary extract. The dry powder compartment contains lutein ester microcapsule powder, zeaxanthin microcapsule powder, blueberry extract, black currant concentrated powder, zinc picolinate, sialic acid, bilberry extract, taurine and L-theanine. The capsule shell is made of gelatin, glycerol, erythritol, sorbitol, purified water, edible essence and natural pigment. The capsule is prepared through microcapsule embedding, high-speed shearing emulsification, double-compartment filling and shaping and drying. The application can improve the stability of lutein, prolong the shelf life and improve the human absorption and utilization rate.

Description

Technical Field

[0001] This invention relates to the field of microencapsulation technology, and in particular to a lutein and flaxseed oil self-emulsifying soft capsule and its preparation method. Background Technology

[0002] With the widespread use of electronic display devices and the increasing trend of population aging, problems such as visual fatigue, macular malnutrition, and cognitive decline have gradually attracted attention. Lutein and zeaxanthin, as important natural carotenoids in the macular region of the human retina, can filter high-energy blue light, scavenge free radicals, and maintain stable visual function, thus becoming important components of eye nutritional supplements.

[0003] Most lutein soft capsules on the market currently use a single-compartment structure, which involves directly mixing lutein, zeaxanthin, and oils such as fish oil and flaxseed oil and then encapsulating them in the same capsule. However, the molecular structures of lutein and zeaxanthin contain multiple conjugated double bonds, making them relatively sensitive to oxygen, light, heat, and free radicals. When stored together with unsaturated fatty acids for a long time, they are prone to oxidative degradation, leading to a decrease in the content of active ingredients during the product's shelf life and affecting its final efficacy.

[0004] On the other hand, to meet the nutritional needs of the eyes and brain in synergistic ways, more and more products are incorporating functional ingredients such as DHA, nervonic acid, phosphatidylserine, coenzyme Q10, and anthocyanins. However, due to the significant differences in properties between fat-soluble and water-soluble components, traditional mixed encapsulation methods suffer from problems such as insufficient stability, low absorption efficiency, and decreased activity retention. (Invention Content)

[0005] In order to at least solve one of the above-mentioned technical problems, the present invention aims to provide a lutein and flaxseed oil self-emulsifying soft capsule and its preparation method, which improves the stability of lutein, extends shelf life, and enhances human absorption and utilization.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A lutein and flaxseed oil self-emulsifying soft capsule, characterized in that it includes a capsule shell, wherein the capsule shell is internally divided into an independent oil phase chamber and a dry powder chamber.

[0008] The oil phase chamber contains camellia seed oil, perilla seed oil, flaxseed oil, MCT medium-chain triglycerides, DHA algal oil, astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, emulsifier, mixed natural tocopherols, and oil-soluble rosemary extract.

[0009] The dry powder compartment contains lutein ester microcapsule powder, zeaxanthin microcapsule powder, blueberry extract, blackcurrant concentrate powder, zinc pyridinecarboxylate, sialic acid, bilberry extract, taurine, and L-theanine.

[0010] The gel is made of biodegradable material, and the oil phase chamber and the dry powder chamber are released simultaneously after ingestion to form a self-emulsifying nutrient delivery system.

[0011] Preferably, the emulsifier is one or more of soybean lecithin, sunflower seed lecithin, phosphatidylcholine, and polyglycerol fatty acid esters.

[0012] Preferably, the contents of the oil phase chamber are composed of the following components by weight: 15-25 parts camellia seed oil; 10-20 parts perilla seed oil; 8-15 parts flaxseed oil; 10-20 parts MCT medium-chain triglycerides; 20-35 parts DHA algal oil; 1-10 parts emulsifier; 1-5 parts astaxanthin oil; 1-5 parts oil-soluble reduced coenzyme Q10; 0.5-3 parts nervonic acid; 1-5 parts oil-soluble GABA; 0.5-3 parts mixed natural tocopherols; 1-2 parts oil-soluble rosemary extract; and 0.5-3 parts phosphatidylserine.

[0013] Preferably, the contents of the dry powder container are composed of the following components by weight: 2-15 parts lutein ester microcapsule powder; 1-8 parts zeaxanthin microcapsule powder; 5-30 parts blueberry extract; 5-25 parts blackcurrant concentrate powder; 2-5 parts zinc pyridinecarboxylate; 2-20 parts sialic acid; 5-25 parts blueberry extract; 2-20 parts taurine; and 2-20 parts L-theanine.

[0014] Preferably, the biodegradable material of the rubber sheet comprises the following components by weight: 60-75 parts gelatin; 15-25 parts glycerin; 8-12 parts erythritol; 5-10 parts sorbitol; 20-30 parts purified water; 0.5-1 part edible flavoring; and 0.5-1 part natural pigment.

[0015] Preferably, the oil phase compartment accounts for 75% to 85% of the total weight of the capsule contents, and the dry powder compartment accounts for 15% to 25% of the total weight of the capsule contents; the volume of the oil phase compartment accounts for 70% to 85% of the effective internal volume of the capsule, and the volume of the dry powder compartment accounts for 15% to 30% of the effective internal volume of the capsule.

[0016] Preferably, both the lutein ester microcapsule powder and the zeaxanthin microcapsule powder form microcapsule structures by encapsulating wall materials, wherein the encapsulating wall materials include one or more combinations of gum arabic, modified starch, and maltodextrin.

[0017] A method for preparing lutein and flaxseed oil self-emulsifying soft capsules includes the following steps:

[0018] S1. Prepare microcapsule powder by encapsulating lutein ester and zeaxanthin using a microcapsule encapsulation process.

[0019] S2. Camellia seed oil, perilla seed oil, flaxseed oil, MCT medium-chain triglycerides, DHA algal oil and emulsifier are mixed to form a self-emulsifying oil phase system;

[0020] S3. Add astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, mixed natural tocopherols and oil-soluble rosemary extract to the self-emulsifying oil phase system, and mix evenly to obtain an oil phase mixture.

[0021] S4. Lutein ester microcapsule powder, zeaxanthin microcapsule powder, blueberry extract, blackcurrant concentrate powder, zinc pyridinecarboxylate, sialic acid, bilberry extract, taurine and L-theanine are mixed evenly to obtain a dry powder mixture.

[0022] S5. Prepare a gelatin solution by mixing gelatin, glycerin, erythritol, sorbitol and purified water;

[0023] S6. Using a dual-compartment soft capsule forming device, the oil phase mixture and the dry powder mixture are filled into the independent compartments respectively, and then covered with rubber to form a dual-compartment soft capsule.

[0024] S7. The formed double-compartment soft capsules are shaped and dried to obtain the self-emulsifying soft capsule product.

[0025] Preferably, in step S2, a pre-emulsified system with an average particle size of 50-500 nm is formed by high-speed shear emulsification or high-pressure homogenization.

[0026] Preferably, the mixing temperature in step S3 is controlled at 40℃ to 50℃; the moisture content of the dry powder in step S4 is controlled at less than 5%; and the moisture content of the finished soft capsules in step S7 is controlled at 6% to 10%.

[0027] The present invention has the following beneficial effects:

[0028] I. Dual-compartment physical isolation significantly improves lutein stability and extends shelf life; This invention places lutein ester microcapsule powder and zeaxanthin microcapsule powder in an independent dry powder compartment, completely isolating them from the unsaturated fatty acids in the oil phase compartment. Lutein and zeaxanthin molecules contain multiple conjugated double bonds, making them highly sensitive to oxygen, light, heat, and free radicals. In traditional single-compartment structures, they coexist with unsaturated fatty acids such as flaxseed oil and DHA algal oil for extended periods, making them highly susceptible to oxidative degradation. The dual-compartment design fundamentally cuts off the contact pathway between lutein and oxidized oils. Combined with the secondary protection of the microcapsule encapsulation wall material, this significantly reduces the loss of active ingredients during shelf life, ensuring that the product maintains the labeled content throughout its shelf life.

[0029] II. The oil-phase storage system employs a multi-antioxidant system to synergistically protect fat-soluble active ingredients. The oil-phase storage is not simply a mixture of oils; rather, it constructs a complex antioxidant network. A blend of natural tocopherols provides basic antioxidant capacity, while oil-soluble rosemary extract, rich in phenolic substances such as sarsaparilla acid, provides powerful free radical scavenging. Astaxanthin, one of the strongest known natural antioxidants, further blocks chain oxidation reactions. This triple antioxidant effect effectively protects high-value unsaturated components such as DHA algal oil, nervonic acid, and oil-soluble reduced coenzyme Q10 during storage and digestion, reducing rancidity and activity degradation.

[0030] Third, the self-emulsifying system significantly improves human absorption and utilization. The oil phase chamber is pre-filled with emulsifiers, and the pre-emulsified system particle size is controlled to 50-500 nanometers using high-speed shearing or high-pressure homogenization processes. After ingestion, the oil phase and dry powder chamber are released simultaneously. The emulsifiers rapidly function in the gastrointestinal fluid, converting fat-soluble components into nano-sized droplets, greatly increasing the contact area with the intestinal wall. Compared to the passive process in traditional soft capsules where fats rely on bile emulsification, the self-emulsifying system actively and efficiently promotes the transmembrane absorption of fat-soluble components, significantly improving bioavailability.

[0031] IV. The dry powder capsule precisely delivers eye-brain synergistic functional ingredients. It contains anthocyanin-rich eye nutrients such as blueberry extract, blackcurrant concentrate, and bilberry extract, as well as cognitive support components like sialic acid, taurine, L-theanine, and zinc pyridinecarboxylate. These ingredients are individually encapsulated in dry powder microcapsules, avoiding stability issues caused by interactions with the oil-based system. Furthermore, anthocyanins are less prone to oxidation in the dry powder environment. Upon ingestion, they are released simultaneously with the oil phase. The anthocyanins and lutein in the oil work synergistically at the absorption level, working together to target the macular region of the retina.

[0032] V. Biodegradable rubber materials balance functionality and environmental protection requirements; the rubber sheet uses gelatin as the main material, with erythritol and sorbitol added to replace some of the glycerin as plasticizers. Erythritol and sorbitol not only reduce the hygroscopicity of the rubber sheet, helping to control the finished product's moisture content within a reasonable range of 6% to 10%, but also give the rubber sheet biodegradable properties, aligning with current green packaging trends. Simultaneously, the use of natural pigments and flavorings avoids artificial synthetic additives, enhancing the product's clean label attributes.

[0033] VI. The combination of MCT medium-chain triglycerides and multi-source oils optimizes digestive burden; MCT medium-chain triglycerides are specially added to the oil phase chamber. MCT can be directly absorbed via the portal vein without bile salt emulsification, providing a rapid energy source for middle-aged and elderly people with weaker digestive function. It complements the long-chain unsaturated fatty acids in camellia seed oil, perilla seed oil, and flaxseed oil, ensuring the supply of essential fatty acids such as alpha-linolenic acid while reducing the overall digestive burden of oils through MCT, making the product more suitable for long-term use.

[0034] VII. The dry powder compartment's microencapsulation and low-moisture control provide dual assurance of stability. Lutein ester microencapsulation powder and zeaxanthin microencapsulation powder are encapsulated using wall materials such as gum arabic, modified starch, and maltodextrin, forming a physical barrier to isolate oxygen and light. The overall moisture content of the dry powder compartment is controlled below 5%. This low-moisture environment further inhibits the Maillard reaction and the risk of microbial growth, ensuring the stability of moisture-sensitive components such as blueberry extract and sialic acid during storage—a feat difficult to achieve simultaneously with traditional mixed packaging methods.

[0035] 8. It is worth noting that the core innovation of this solution lies not in the selection of a single ingredient, but in the decoupling of the "protection" and "release" stages by the dual-compartment architecture. Lutein is isolated and protected during the storage stage, and only merges with the oil phase to form a self-emulsifying system during the consumption stage. This time-sharing strategy systematically solves the stability problem of the entire chain of active ingredients from production to absorption more comprehensively than simply adding antioxidants. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a cross-sectional view of the soft capsule of Embodiment 1 of the present invention.

[0038] Figure 2 This is a flowchart of the preparation process in Example 1 of the present invention. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] All raw materials used in this invention are commercially available. Specifically, the lutein ester content is preferably above 80%, and the zeaxanthin content is preferably above 10%; the DHA content in the DHA algal oil is preferably not less than 40%; the α-linolenic acid content in the flaxseed oil is preferably not less than 50%; and the α-linolenic acid content in the perilla seed oil is preferably not less than 55%.

[0041] This invention provides a lutein and flaxseed oil self-emulsifying soft capsule, comprising a capsule shell and an oil phase compartment and a dry powder compartment encapsulated within the capsule shell. The oil phase compartment and the dry powder compartment form an independent sealed structure through the capsule shell, and an insulating adhesive layer is disposed between the two compartments. Preferably, the volume of the oil phase compartment accounts for 70% to 85% of the effective internal volume of the capsule, and the volume of the dry powder compartment accounts for 15% to 30% of the effective internal volume of the capsule; the mass of the oil phase compartment accounts for 75% to 85% of the total internal mass, and the mass of the dry powder compartment accounts for 15% to 25% of the total internal mass; the thickness of the insulating adhesive layer is 0.15 to 0.50 mm, more preferably 0.20 to 0.35 mm; the total filling amount of each soft capsule is 1000 to 1500 mg, of which the filling amount of the oil phase compartment is 800 to 1200 mg and the filling amount of the dry powder compartment is 200 to 300 mg. Lutein ester microcapsule powder and zeaxanthin microcapsule powder are coated with an embedding wall material, which includes one or more of gum arabic, modified starch and maltodextrin. Preferably, the average particle size of lutein ester microcapsule powder and zeaxanthin microcapsule powder is 5 to 30 μm.

[0042] Example 1

[0043] like Figures 1 to 2 As shown, this embodiment provides a lutein and flaxseed oil self-emulsifying soft capsule, comprising an oil phase chamber and a dry powder chamber that are independently arranged. The oil phase chamber, by weight, comprises: 20 parts camellia seed oil, 15 parts perilla seed oil, 12 parts flaxseed oil, 15 parts MCT medium-chain triglycerides, 28 parts DHA algal oil, 4 parts soybean lecithin, 2 parts astaxanthin oil, 2 parts oil-soluble reduced coenzyme Q10, 1 part nervonic acid, 2 parts oil-soluble GABA, 1 part phosphatidylserine, 1 part mixed natural tocopherols, and 1 part oil-soluble rosemary extract. The dry powder chamber, by weight, comprises: 10 parts lutein ester microcapsule powder, 3 parts zeaxanthin microcapsule powder, 15 parts blueberry extract, 10 parts blackcurrant concentrate powder, 3 parts zinc pyridinecarboxylate, 8 parts sialic acid, 12 parts bilberry extract, 10 parts taurine, and 8 parts L-theanine.

[0044] The preparation method of lutein ester microcapsule powder is as follows: lutein ester, gum arabic, modified starch, and maltodextrin are mixed in a mass ratio of 1:2:1:1, and an appropriate amount of purified water is added to form a homogeneous emulsion. After shearing at 10,000 rpm for 10 minutes using a high-speed emulsifier, the mixture is spray-dried in a pressure spray drying tower at an inlet air temperature of 180℃ and an outlet air temperature of 80℃. The collected microcapsule powder has an encapsulation rate of not less than 92%. Zeaxanthin microcapsule powder is prepared using the same process, with an encapsulation rate of not less than 90%.

[0045] In preparing the soft capsules, camellia seed oil, perilla seed oil, flaxseed oil, MCT medium-chain triglycerides, DHA algal oil, and soybean lecithin were first added to a stainless steel homogenizing tank. The mixture was heated to 45°C and maintained at that temperature. The phospholipids were then fully dispersed by high-speed shearing at 8000 rpm for 20 minutes. Subsequently, the mixture was homogenized twice under 60 MPa pressure using a high-pressure homogenizer to form a pre-emulsified system with an average particle size of approximately 180 nm. Then, astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, mixed natural tocopherols, and oil-soluble rosemary extract were sequentially added to the pre-emulsified system and stirred at low speed at 2000 rpm for 10 minutes to obtain a homogeneous oil phase mixture.

[0046] Lutein ester microcapsule powder, zeaxanthin microcapsule powder, blueberry extract, blackcurrant concentrate powder, zinc pyridinecarboxylate, sialic acid, bilberry extract, taurine, and L-theanine were placed in a V-type mixer and mixed at 30 rpm for 20 minutes to obtain a dry powder mixture. Samples were taken and measured according to the direct drying method of GB 5009.3, with the moisture content controlled below 5%. Subsequently, a dual-compartment soft capsule pressing device (such as the ROTO CFS-N model) was used to quantitatively fill the oil phase compartment and the dry powder compartment, with the filling mass ratio of the oil phase compartment to the dry powder compartment controlled at 80:20. After being rolled and molded, the capsules were dried in a constant temperature and humidity chamber at 22℃ and 25% relative humidity for 48 hours to reduce the moisture content of the capsule shells to 6% to 10%, resulting in the finished product of lutein and flaxseed oil self-emulsified soft capsules.

[0047] Example 2

[0048] This embodiment provides a lutein and flaxseed oil self-emulsifying soft capsule, with a composition basically the same as in Example 1, except that: 6 parts sunflower seed lecithin are used instead of soybean lecithin as the emulsifier, and the high-pressure homogenization pressure is increased to 80 MPa and the number of homogenization cycles is increased to three, resulting in a pre-emulsified system with an average particle size of approximately 120 nm. The remaining preparation process is exactly the same as in Example 1. The final obtained dual-compartment self-emulsifying soft capsule has a uniform and intact appearance, no cracks in the capsule wall, and no leakage of contents. After centrifugation (3000 rpm, 10 min), the oil phase compartment and the dry powder compartment remain independent and do not overlap.

[0049] Example 3

[0050] This embodiment provides a lutein and flaxseed oil self-emulsifying soft capsule. The oil phase compartment, by weight, comprises: 20 parts camellia seed oil, 15 parts perilla seed oil, 15 parts flaxseed oil, 15 parts MCT medium-chain triglycerides, 25 parts DHA algal oil, 5 parts phosphatidylcholine, 2 parts polyglycerol fatty acid esters, 4 parts astaxanthin oil, 3 parts oil-soluble reduced coenzyme Q10, 2 parts nervonic acid, 3 parts oil-soluble GABA, 2 parts phosphatidylserine, 2 parts mixed natural tocopherols, and 1.5 parts oil-soluble rosemary extract. The composition of the dry powder compartment is the same as in Example 1. In preparation, camellia seed oil, perilla seed oil, flaxseed oil, MCT medium-chain triglycerides, DHA algal oil, phosphatidylcholine, and polyglycerol fatty acid esters were first added to a homogenizing tank and sheared at 8000 rpm for 15 minutes at 45°C. Then, the mixture was homogenized three times at 80 MPa using a high-pressure homogenizer to form a composite emulsion pre-emulsified system with an average particle size of approximately 95 nm. Subsequently, the remaining oil-soluble active ingredients were added and mixed thoroughly. The dry powder was mixed for 20 minutes using a V-type mixer, with the moisture content controlled below 5%. The dual-compartment filling process was the same as in Example 1. The resulting product exhibited excellent self-emulsifying properties. One capsule was placed in 250 mL of simulated intestinal fluid (pH 6.8, containing 0.5% Tween 80) at 37°C. After gentle shaking, it completely disintegrated within 30 seconds and rapidly formed a uniform emulsion without any oil droplets floating on the surface.

[0051] Example 4

[0052] This embodiment is a preferred embodiment of the present invention. The oil phase chamber, by weight, comprises: 20 parts camellia seed oil, 15 parts perilla seed oil, 12 parts flaxseed oil, 15 parts MCT medium-chain triglycerides, 30 parts DHA algal oil, 4 parts soybean lecithin, 2 parts phosphatidylcholine, 3 parts astaxanthin oil, 3 parts oil-soluble reduced coenzyme Q10, 2 parts nervonic acid, 3 parts oil-soluble GABA, 2 parts phosphatidylserine, 2 parts mixed natural tocopherols, and 1 part oil-soluble rosemary extract; the dry powder chamber, by weight, comprises: 12 parts lutein ester microcapsule powder, 5 parts zeaxanthin microcapsule powder, 20 parts blueberry extract, 15 parts blackcurrant concentrate powder, 4 parts zinc pyridinecarboxylate, 10 parts sialic acid, 18 parts blueberry extract, 12 parts taurine, and 10 parts L-theanine. In the preparation process, the main oil phase component was first sheared at 45℃ and 8000rpm for 15min, followed by homogenization three times at 70MPa using a high-pressure homogenizer to form a pre-emulsified system with an average particle size of approximately 105nm. Then, astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, mixed natural tocopherols, and oil-soluble rosemary extract were added sequentially and stirred at 2000rpm for 10min to achieve homogenization. The dry powder was then mixed in a V-type mixer for 20min, with the moisture content controlled below 5%. The dual-compartment filling mass ratio was 80:20, and after roll molding, it was dried at 22℃ and 25% relative humidity for 48h. One finished product was placed in 250 mL of simulated intestinal fluid (pH 6.8) at 37℃ and shaken at a constant temperature of 50 rpm. The particle size was measured using a Malvern Zetasizer Nano ZS90 laser particle size analyzer. It can complete self-emulsification within 42 s. The average particle size after emulsification is about 135 nm, the polydispersity index (PDI) is less than 0.2, and a uniform and stable nanoemulsion system is formed. There is no stratification after standing for 2 h.

[0053] Comparative Example 1

[0054] Using a traditional single-compartment soft capsule structure, all components of the oil phase in Example 4 and all components of the dry powder compartment were mixed in a V-type mixer for 20 minutes. After controlling the moisture content to be less than 5%, the mixture was directly filled into the same soft capsule using a single-compartment soft capsule device. After being rolled and pressed, the capsules were dried at 22°C and 25% relative humidity for 48 hours to obtain single-compartment lutein soft capsules.

[0055] Comparative Example 2

[0056] Using the same dual-compartment structure and formulation as in Example 4, but without adding soybean lecithin and phosphatidylcholine to the oil phase system, and with all other process conditions identical to Example 4, an emulsifier-free dual-compartment soft capsule was obtained. One capsule was placed in simulated intestinal fluid at 37°C, and after shaking for 5 minutes, noticeable oil droplets were still visible, indicating that a uniform emulsion had not formed.

[0057] Comparative Example 3

[0058] Using the same formulation and dual-compartment structure as in Example 4, but without microencapsulation of lutein esters and zeaxanthin, they were directly added to the dry powder compartment as raw material powder. The remaining process conditions were completely consistent with those in Example 4, resulting in non-microencapsulated dual-compartment soft capsules.

[0059] Accelerated stability test

[0060] Three batches of samples from Examples 1 to 4 and Comparative Examples 1 to 3 were taken and stored in a constant temperature and humidity accelerating chamber at 40℃±2℃ and relative humidity of 75%±5% for 6 months. Samples were taken at 0, 1, 2, 3, and 6 months, and the lutein content was determined by HPLC (C18 column, mobile phase: methanol:acetonitrile:water = 80:10:10, detection wavelength 450nm). The lutein retention rate was calculated. The results showed that the lutein retention rate of Comparative Example 1 (single-compartment structure) was 78.5%, and that of Comparative Example 3 (unmicroencapsulated) was 84.2%. Examples 1 to 3, due to the use of dual-compartment isolation and microencapsulation protection, had retention rates of 91.3%, 93.7%, and 94.8%, respectively. Example 4 (preferred example), due to the simultaneous use of dual-compartment isolation, microencapsulation, and a composite antioxidant system, achieved a lutein retention rate of 96.1% after 6 months, which was significantly better than the comparative examples.

[0061] Long-term shelf life test

[0062] Three batches each of the samples from Example 4 and Comparative Example 1 were taken and stored at 25℃±2℃ and 60%±5% relative humidity for 18 months according to commercial packaging. Peroxide value (according to GB 5009.227) and lutein content were measured every 3 months. The results showed that after 18 months, the peroxide value of Example 4 was only 3.9 meq / kg, and the lutein retention rate was 93.6%; the peroxide value of Comparative Example 1 reached 11.6 meq / kg in the 9th month, and the lutein retention rate decreased to 71.2% after 18 months.

[0063] Biological accessibility testing

[0064] Using an in vitro simulated digestion model (INFOGEST 2.0 standard), samples from Examples 2 to 4 and Comparative Examples 1 to 2 were successively digested in the oral phase (pH 7.0, 2 min), gastric phase (pH 3.0, containing pepsin 3.2 mg / mL, 2 h), and intestinal phase (pH 6.8, containing pancreatic lipase and bile salts, 2 h). The intestinal digest was then ultracentrifuged (10000 g, 30 min), and the lutein concentration in the supernatant was measured. Bioavailability was calculated (the percentage of bioavailability equals the amount of lutein in the supernatant after digestion divided by the total amount of lutein in the capsule, multiplied by 100%). The results showed that: Comparative Example 1 had a bioavailability of 42.1%, Comparative Example 2 (without emulsifier) ​​had a bioavailability of 58.4%; Example 2 had a bioavailability of 78.5%, Example 3 had a bioavailability of 85.2%; and Example 4, due to its self-emulsifying system that released the active ingredient in the form of a nanoemulsion, achieved a bioavailability of 89.6%.

[0065] Oxidative stability test

[0066] Five g of oil phase samples from Examples 4 and Comparative Examples 1 to 3 were placed in an open oven at 60°C for 15 days. Peroxide value and astaxanthin residue were measured every 5 days (HPLC method, detection wavelength 476 nm). The results showed that in Example 4, the astaxanthin residue rate after 15 days was 87.3%, and the peroxide value was 5.2 meq / kg; in Comparative Example 1, the astaxanthin residue rate was only 41.6%, and the peroxide value reached 18.7 meq / kg. This indicates that the composite antioxidant system composed of astaxanthin, mixed natural tocopherols, and oil-soluble rosemary extract can effectively delay lipid oxidation.

[0067] Self-emulsifying performance test

[0068] One sample from each of Examples 1 to 4 and Comparative Examples 2 to 3 was added to 250 mL of simulated intestinal fluid (pH 6.8, containing 0.5% Tween 80) at 37°C. The mixture was shaken at a constant temperature of 50 rpm, and samples were taken every 10 seconds to measure the emulsion particle size using a laser particle size analyzer. The time required to achieve stable emulsification (PDI less than 0.3 and particle size change less than 5 nm / min) was recorded. The results showed that: Comparative Example 2, lacking emulsifier, had not completed emulsification after 300 seconds; Comparative Example 3 took 185 seconds; Example 1 took 68 seconds (particle size 168 nm), Example 2 took 52 seconds (particle size 142 nm), and Example 3 took 38 seconds (particle size 131 nm); Example 4 achieved stable emulsification in only 42 seconds, with a final particle size of 135 nm and a PDI of 0.17.

[0069] ω-3 fatty acid release rate test

[0070] Samples from Example 4 and Comparative Example 1 were processed using the same in vitro digestion procedure as described in the bioaccessibility test. The intestinal digestate was extracted with chloroform at a ratio of 2:1 (volume ratio) to methanol, dried under nitrogen, and the contents of α-linolenic acid and DHA were determined by gas chromatography (FID detector, DB-23 capillary column, programmed temperature rise: 170℃ for 2 min, then increased to 220℃ at 4℃ / min and held for 5 min). The release rate was calculated (the amount released after digestion divided by the total amount in the capsule and then multiplied by 100%). The results showed that the release rate of α-linolenic acid in Example 4 was 92.4%, and the release rate of DHA was 90.7%; the release rate of α-linolenic acid in Comparative Example 1 was 63.1%, and the release rate of DHA was 57.8%. This indicates that the dual-compartment structure combined with the self-emulsifying system can significantly improve the digestion and release efficiency of ω-3 fatty acids.

[0071] In summary, this invention avoids direct contact between oils and powders through dual-compartment physical isolation, blocks oxidation and photodegradation through microencapsulation of lutein and zeaxanthin, improves digestion and release efficiency through a self-emulsifying nanodelivery system, and synergistically inhibits oil oxidation through a triple-combined antioxidant system of astaxanthin, natural tocopherol, and rosemary extract, thus achieving simultaneous improvement in the shelf-life stability and bioavailability of active ingredients.

[0072] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of the present invention.

Claims

1. A self-emulsifying soft capsule of lutein and flaxseed oil, characterized in that, Includes a rubber sheet, the interior of which is divided into an independent oil phase compartment and a dry powder compartment; The oil phase chamber contains camellia seed oil, perilla seed oil, flaxseed oil, MCT medium-chain triglycerides, DHA algal oil, astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, emulsifier, mixed natural tocopherols, and oil-soluble rosemary extract. The dry powder compartment contains lutein ester microcapsule powder, zeaxanthin microcapsule powder, blueberry extract, blackcurrant concentrate powder, zinc pyridinecarboxylate, sialic acid, bilberry extract, taurine, and L-theanine. The gel is made of biodegradable material, and the oil phase chamber and the dry powder chamber are released simultaneously after ingestion to form a self-emulsifying nutrient delivery system.

2. The lutein and flaxseed oil self-emulsifying soft capsule according to claim 1, characterized in that, The emulsifier is one or more of soybean lecithin, sunflower seed lecithin, phosphatidylcholine, and polyglycerol fatty acid esters.

3. The lutein and flaxseed oil self-emulsifying soft capsule according to claim 1, characterized in that, The contents of the oil phase chamber are composed of the following parts by weight: 15-25 parts camellia seed oil; 10-20 parts perilla seed oil; 8-15 parts flaxseed oil; 10-20 parts MCT medium-chain triglycerides; 20-35 parts DHA algal oil; 1-10 parts emulsifier; 1-5 parts astaxanthin oil; 1-5 parts oil-soluble reduced coenzyme Q10; 0.5-3 parts nervonic acid; 1-5 parts oil-soluble GABA; 0.5-3 parts mixed natural tocopherols; 0.1-2 parts oil-soluble rosemary extract; and 0.5-3 parts phosphatidylserine.

4. The lutein and flaxseed oil self-emulsifying soft capsule according to claim 3, characterized in that, The contents of the dry powder container are composed of the following parts by weight: 2-15 parts of lutein ester microcapsule powder; 1-8 parts of zeaxanthin microcapsule powder; 5-30 parts of blueberry extract; 5-25 parts of blackcurrant concentrate powder; 0.2-5 parts of zinc pyridinecarboxylate; 2-20 parts of sialic acid; 5-25 parts of blueberry extract; 2-20 parts of taurine; and 2-20 parts of L-theanine.

5. The lutein and flaxseed oil self-emulsifying soft capsule according to claim 4, characterized in that, The biodegradable material of the rubber sheet comprises the following components by weight: 60-75 parts gelatin; 15-25 parts glycerin; 8-12 parts erythritol; 5-10 parts sorbitol; 20-30 parts purified water; 0.05-1 part edible flavor; and 0.05-1 part natural pigment.

6. The lutein and flaxseed oil self-emulsifying soft capsule according to claim 1, characterized in that, The oil phase compartment accounts for 75% to 85% of the total weight of the capsule contents, and the dry powder compartment accounts for 15% to 25% of the total weight of the capsule contents; the volume of the oil phase compartment accounts for 70% to 85% of the effective internal volume of the capsule, and the volume of the dry powder compartment accounts for 15% to 30% of the effective internal volume of the capsule.

7. The lutein and flaxseed oil self-emulsifying soft capsule according to claim 1, characterized in that, Both the lutein ester microcapsule powder and the zeaxanthin microcapsule powder form microcapsule structures by encapsulating wall materials, which include one or more combinations of gum arabic, modified starch, and maltodextrin.

8. A method for preparing a self-emulsifying soft capsule of lutein and flaxseed oil as described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Prepare microcapsule powder by encapsulating lutein ester and zeaxanthin using a microcapsule encapsulation process. S2. Camellia seed oil, perilla seed oil, flaxseed oil, MCT medium-chain triglycerides, DHA algal oil and emulsifier are mixed to form a self-emulsifying oil phase system; S3. Add astaxanthin oil, oil-soluble reduced coenzyme Q10, nervonic acid, oil-soluble GABA, phosphatidylserine, mixed natural tocopherols and oil-soluble rosemary extract to the self-emulsifying oil phase system, and mix evenly to obtain an oil phase mixture. S4. Lutein ester microcapsule powder, zeaxanthin microcapsule powder, blueberry extract, blackcurrant concentrate powder, zinc pyridinecarboxylate, sialic acid, bilberry extract, taurine and L-theanine are mixed evenly to obtain a dry powder mixture. S5. Prepare a gelatin solution by mixing gelatin, glycerin, erythritol, sorbitol and purified water; S6. Using a dual-compartment soft capsule forming device, the oil phase mixture and the dry powder mixture are filled into the independent compartments respectively, and then covered with rubber to form a dual-compartment soft capsule. S7. The formed double-compartment soft capsules are shaped and dried to obtain the self-emulsifying soft capsule product.

9. The preparation method according to claim 8, characterized in that, In step S2, a pre-emulsified system with an average particle size of 50–500 nm is formed using high-speed shear emulsification or high-pressure homogenization processes.

10. The preparation method according to claim 8, characterized in that, The mixing temperature in step S3 is controlled at 40℃ to 50℃; the moisture content of the dry powder in step S4 is controlled at less than 5%; and the moisture content of the finished soft capsules in step S7 is controlled at 6% to 10%.

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