Structural lipid for improving cognitive impairment of old people and preparation method of structural lipid

Abstract

The invention discloses structural lipid for improving cognitive impairment of old people and a preparation method of the structural lipid. Immobilized lipase is filled into a continuous flow bio-enzyme catalytic reaction column, and nitrogen charging treatment is carried out; the preparation method comprises the following steps: uniformly stirring and mixing sn-2-site triglyceride with DHA mass content of 65% or above and n-caprylic acid to obtain a reaction solution; and pumping the reaction liquid into a continuous flow bio-enzyme catalytic reaction column to obtain mixed lipid, and carrying out deacidification and dehydration treatment to obtain the structural lipid. According to the invention, the humic acid peculiar smell of n-caprylic acid and the fishy smell of DHA are obviously improved, and the flavor acceptance is improved; meanwhile, the defects of strong irritation of high-dose n-caprylic acid, poor oxidation stability of DHA, low absorption rate and the like are effectively overcome, and the functional safety and the quality stability of the product are enhanced. The structural lipid shows a synergistic effect in the aspect of improving cognitive impairment, is suitable for nutrition intervention of aging or neurodegenerative diseases, and has a good application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional lipid biosynthesis and processing, and in particular relates to a structural lipid for improving senile cognitive impairment and a preparation method thereof. Background Art

[0002] The detection rate of cognitive impairment in the population aged 60 and above in my country is as high as 30.59%. Cognitive impairment in the elderly related to neurodegenerative diseases has become a major challenge in the field of nutrition. Unlike infection by external pathogens, cognitive impairment mainly stems from imbalance in brain energy metabolism and neurological degeneration. Although traditional early drug intervention methods can alleviate some symptoms, they may destroy the normal function of the body's genes or proteins and have certain risks of side effects. In contrast, dietary nutritional supplements provide a safer and more economical intervention plan by holistically regulating the nutritional environment and improving signal transduction pathways.

[0003] Structured lipids are a type of functional lipid obtained by chemically or enzymatically redistributing or modifying the fatty acid composition of triglycerides. They possess a specific fatty acid positioning structure at the molecular level. Among them, medium- and long-chain triglycerides (MLCTs), as an important type of structured lipid, are widely used in conventional foods, dietary supplements, and special medical foods. MLCTs contain both medium-chain fatty acids (C8-C12) and long-chain fatty acids (>C12). However, current MLCT products generally suffer from issues such as inaccurate structural positioning and low bioavailability, making it difficult to precisely address specific nutritional needs.

[0004] Compared to other medium-chain fatty acids, octanoic acid (C8:0) is more effective in promoting brain energy metabolism, but excessive intake can easily cause dose-dependent gastrointestinal discomfort. Furthermore, traditional single-ingredient docosahexaenoic acid (DHA) glycerides have limited effects on improving age-related neurological degeneration and suffer from defects such as a noticeable fishy odor and poor oxidative stability. Studies have shown that when C8:0 is located at the sn-1 / 3 position of the glyceride, it can effectively increase its metabolic rate while reducing the intake dose of C8:0, thereby promoting energy metabolism homeostasis in brain neurons. Furthermore, when DHA is located at the sn-2 position of the glyceride, the sn-2-DHA, after hydrolysis by pancreatic lipase in the body, can be absorbed more rapidly by intestinal epithelial cells, with an absorption efficiency twice that of ordinary sn-1 / 3-DHA, and can significantly enhance the protective effect on neurological function. Based on the above evidence, synthetic structured lipids rich in sn-1,3-C8:0-sn-2-DHA can synergistically meet the dual needs of "energy homeostasis and neuroprotection" in the intervention of elderly cognitive impairment, and achieve precise nutritional intervention.

[0005] Limitations of existing MLCT synthesis technologies include both raw material structure and synthesis methods. With the exception of MLCTs in infant formula, which are limited to C14-C18 saturated long-chain fatty acids, other MLCTs generally do not specify the type and position of C8:0 or DHA. This is primarily due to the scarcity of high-purity C8:0-derived oils and fats, and existing technology routes often fail to effectively utilize C8:0's rapid energy supply. Secondly, the low content of sn-2 DHA in conventional oils and fats, or the poor selective enrichment of sn-2 DHA by the selected technologies, results in low yields or purity of structured lipids with sn-2 DHA distribution, ultimately limiting the efficacy of existing MLCTs in improving cognitive impairment in the elderly. Furthermore, MLCT synthesis primarily utilizes traditional chemical or immobilized enzymatic methods, and the reaction mode primarily relies on static autoclave reactions. Chemical methods utilize strong alkaline catalysts, which pose environmental risks. Traditional enzymatic methods, on the other hand, face industrial bottlenecks such as long reaction times and low specific production capacity.

[0006] Therefore, in order to achieve the synergistic enhancement of C8:0 and DHA, developing a sn-1,3-C8:0-sn-2-DHA structured lipid with clear structural characteristics that can effectively improve cognitive impairment in the elderly and its efficient and green preparation method is a technical problem that urgently needs to be broken through in this field. Summary of the Invention

[0007] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of this application to avoid obscuring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions should not be used to limit the scope of the present invention.

[0008] As one aspect of the present invention, the present invention provides a method for preparing a structured lipid for improving cognitive impairment in the elderly, wherein the reaction scheme is:

[0009] The present invention provides a method for preparing a structured lipid for improving cognitive impairment in the elderly, comprising the following steps: The immobilized lipase is filled into a continuous flow bio-enzyme catalytic reaction column and nitrogen-filled. Stirring and mixing triglyceride having a sn-2 DHA content of more than 65% and n-octanoic acid to obtain a reaction solution; The reaction solution is pumped into a continuous flow bio-enzyme catalytic reaction column to obtain a mixed lipid, which is then subjected to deacidification and dehydration treatment to obtain the structured lipid.

[0010] As a preferred embodiment of the method for preparing the structured lipid for improving cognitive impairment in the elderly according to the present invention, the immobilized lipase includes one or more of lipase Lipozyme TL IM, lipase R IM-03 or lipase IM-NE100.

[0011] As a preferred solution of the method for preparing the structural lipid for improving cognitive impairment in the elderly according to the present invention, the mixing is uniform and the mixing temperature is 30-60°C.

[0012] As a preferred solution of the method for preparing the structural lipid for improving cognitive impairment in the elderly according to the present invention, the mixing is uniform, the mixing temperature is 45-55° C., and the mixing time is 10-30 min.

[0013] As a preferred solution of the method for preparing the structured lipid for improving cognitive impairment in the elderly according to the present invention, the reaction solution is pumped into a continuous flow bio-enzyme catalysis reaction column at a temperature of 30-60°C.

[0014] As a preferred solution of the method for preparing the structured lipid for improving cognitive impairment in the elderly according to the present invention, the reaction solution is pumped into a continuous flow bio-enzyme catalysis reaction column at a temperature of 45-55°C.

[0015] As a preferred solution of the method for preparing the structured lipid for improving cognitive impairment in the elderly according to the present invention, the reaction solution is pumped into a continuous flow bio-enzyme catalytic reaction column at a flow rate of 0.25-1.0 mL / min.

[0016] As a preferred embodiment of the method for preparing the structured lipid for improving cognitive impairment in the elderly according to the present invention, the molar ratio of triglyceride with a sn-2 DHA content of more than 65% to n-octanoic acid is 1:2-6.

[0017] Beneficial effects of the present invention: The present invention constructs a structural lipid rich in sn-1,3-C8:0-sn-2-DHA triglyceride. In terms of molecular structure, DHA, which has a strong neuroprotective function, is located at the sn-2 position. At the same time, the medium-chain fatty acid n-octanoic acid (C8:0), which has a fast metabolic rate and rapid energy supply, is introduced at the sn-1,3 position. This achieves the dual nutritional synergistic intervention of "energy homeostasis and neuroprotection", effectively overcoming the limitations of using DHA and n-octanoic acid alone. The specific performance is as follows: (1) In the obtained structural lipid, DHA is efficiently positioned at the sn-2 position, and its absorption efficiency is twice that of ordinary DHA, significantly improving the bioavailability of DHA. At the same time, n-octanoic acid is only positioned at the sn-1,3 position, which effectively reduces the dosage intensity by about 33% compared with traditional tricaprylin. It can also be rapidly hydrolyzed under the action of gastrointestinal pancreatic lipase, promoting the homeostasis of brain neuronal energy metabolism. This molecular structure takes into account high absorption, high energy supply and high safety. It has shown a significant effect of improving motor ability and perception in animal models of elderly cognitive impairment, which is superior to DHA or n-octanoic acid substrates alone, and has a clear synergistic advantage.

[0018] (2) The product of the present invention showed no significant toxic side effects in a simulated in vivo evaluation, overcoming the drawbacks of strong irritating odor and poor ingestion safety of octanoic acid when used alone. Furthermore, by placing DHA at the sn-2 position in the middle of the glycerol backbone, the octanoic acid at the sn-1 / 3 position nearby can effectively protect DHA, reducing the odor and safety risks caused by oxidation. In sensory evaluation, compared to the comparative product, the structural lipid exhibited significantly reduced odor caused by octanoic acid or DHA, improving flavor and consumer acceptance, and possessing the practical feasibility of food development.

[0019] (3) The present invention uses a continuous flow immobilized enzyme catalytic reaction, optimizes substrate structure and reaction conditions, shortens synthesis time to within 2 hours, and achieves a product with a sn-1,3-C8:0-sn-2-DHA content exceeding 60%, and a total triglyceride purity exceeding 85% as determined by HPLC. Compared to conventional static enzymatic methods with product contents <50% and reaction times >5 hours, efficiency and quality are significantly improved.

[0020] (4) The continuous flow system has excellent mass and heat transfer performance, which can precisely control the reaction temperature and flow rate, improving process consistency and safety. The immobilized enzyme has a long service life and can be reused more than 30 times. The process is environmentally friendly and low-cost, meeting the needs of green manufacturing and industrial production. The process is controllable, safe and environmentally friendly, and is conducive to industrial scale-up.

[0021] (5) The sn-1,3-C8:0-sn-2-DHA structured lipid prepared by the present invention can be widely used in many fields such as ordinary food, dietary supplements, special medical food, etc., and is particularly suitable for nutritional intervention for the elderly, patients with neurodegenerative diseases, and people at risk of cognitive dysfunction. It has good market transformation prospects and social value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them: Figure 1 This is a schematic structural diagram of the continuous flow reaction device used in the present invention.

[0023] Figure 2 This is a diagram showing the effect of the structural lipid of the present invention on improving movement and perception disorders in Caenorhabditis elegans.

[0024] Figure 3 This is the HPLC liquid chromatogram of the structural lipid of the present invention, showing that triglyceride is the main component of the structural lipid, with a proportion of 96%.

[0025] Figure 4 The effects of the products of the examples and comparative examples of the present invention on the body length development of C. elegans. ** indicates p < 0.01.

[0026] Figure 5 The effects of the products of the examples and comparative examples of the present invention on the motor activity (body swing frequency) of Caenorhabditis elegans are shown in Figure 1. Different lowercase letters indicate significant differences, p < 0.05.

[0027] Figure 6 The effects of the products of the examples and comparative examples of the present invention on the barrier-sensing activity (chemotaxis index) of Caenorhabditis elegans are shown in Figure 1. Different lowercase letters indicate significant differences, p < 0.05.

[0028] Figure 7 It is the QDA radar chart of Example product 1 of the present invention and comparative example products 13 and 14. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with specific embodiments.

[0030] The fatty acid composition analysis was carried out with reference to GB 5009.168-2016 National Food Safety Standard Determination of Fatty Acids in Foods.

[0031] The HPLC-RID method for triglyceride determination used the following chromatographic conditions: Sepax HP-Silica column (4.6 mm × 250 mm × 5 μm), column temperature 25°C; sample concentration approximately 20 mg / mL, injection volume 20 μL; mobile phase ratio of n-hexane:isopropanol:formic acid 15:1:0.003 (v / v / v), flow rate 1 mL / min. One drop of oil sample was placed in a centrifuge tube, 1 mL of mobile phase was added, and the mixture was shaken for 30 seconds. Sample preparation was completed by aspirating through the membrane using a syringe. Lipid components were qualitatively analyzed using standards. A linear relationship between sample concentration and peak area was observed. The relative composition of each substance was expressed as % by area normalization.

[0032] Determination of sn-2 fatty acid composition: Pancreatic esterase specifically hydrolyzes the sn-1,3 fatty acids of triglycerides to produce 2-MAG, whose fatty acid composition, i.e., the sn-2 fatty acid composition of the triglycerides, is determined. 100 mg of oil is placed in a centrifuge tube and emulsified with 2 mL of 1 mol / L Tris buffer (pH 8.0), 0.5 mL of 0.05% bile salt solution, and 0.2 mL of 2.2% calcium chloride solution. Then, 40 mg of pancreatic esterase is added, mixed thoroughly, and the mixture is shaken at 40°C for 3 minutes. The reaction is then inactivated by adding 1 mL of 6 mol / L hydrochloric acid solution. The lipids are extracted with 2 mL of ether and concentrated to 200 μL under nitrogen purge. The concentrated lipids are separated by thin-layer chromatography. The developing solvent was n-hexane: ether: acetic acid (50:50:1, v / v / v). The corresponding sn-2 monoglyceride band after separation was scraped off, extracted twice with ether, and then blown with nitrogen to obtain 2-MAG. The fatty acid composition of 2-MAG was analyzed by GC.

[0033] Triglycerides (DHA ORIGINS 580): provided by Fermentalg, France, product number 08103, with a sn-2 DHA content of approximately 70%. Caprylic acid: purchased from Shanghai Yien Chemical Technology Co., Ltd., Ron Reagent, product number R002004-500mL, purity ≥99%.

[0034] Example 1: Immobilized lipase IM-NE100 (2.0 g) was filled into a continuous flow bio-enzymatic reaction column (Ø1.4 cm × 10 cm) and nitrogen was applied (pressure 0.1 MPa, flow rate 75 mL / min, duration 15 min). Triglycerides with a sn-2 DHA mass content of 70% and octanoic acid (molar ratio 1:4) were stirred and mixed uniformly in a preheater at 45°C for 15 min to obtain a reaction solution. The reaction solution was pumped into a continuous flow bio-enzymatic reaction column at a flow rate of 0.5 mL / min. The circulation temperature of the reaction column was set at 45°C to obtain a mixed lipid. The collected mixed lipid was deacidified and dehydrated to obtain a structured lipid with a mass percentage of 1,3-octanoyl-2-DHA of 68.5% and a proportion of octanoic acid in triglycerides of 62.4%, labeled 1.

[0035] Example 2:

[0036] Triglyceride and n-octanoic acid were used as substrates, and the immobilized lipase was replaced by Lipozyme TL IM or Lipase RIM-03, respectively. Other synthesis experimental parameters were referred to Example 1. The composition of the obtained structured lipid is shown below.

[0037] Table 1. Structural lipid compositions obtained using different lipase types

[0038] Example 3: Triglyceride and n-octanoic acid were used as substrates, and the molar ratio of triglyceride to n-octanoic acid was adjusted to 1:2 or 1:6, respectively. Other synthesis experimental parameters were referred to Example 1. The composition of the obtained structured lipid is shown below.

[0039] Table 2. Structural lipid compositions obtained using different substrate molar ratios

[0040] Example 4: Triglyceride and n-octanoic acid were used as substrates, the reaction temperature was set to 30° C. or 60° C., and other synthesis experimental parameters were the same as those in Example 1. The composition of the obtained structured lipid was shown below.

[0041] Table 3. Structural lipid compositions obtained using different cycle temperatures

[0042] Example 5: Triglyceride and n-octanoic acid were used as substrates, and the flow rates were set to 0.25 mL / min or 1.0 mL / min, respectively. Other synthesis experimental parameters were the same as in Example 1. The composition of the obtained structured lipid is shown below.

[0043] Table 4. Structural lipid compositions obtained at different reaction flow rates

[0044] Comparative Example 1: Triglyceride and n-octanoic acid were used as substrates without nitrogen treatment. Other synthesis experimental parameters were the same as those in Example 1. The mass percentage of 1,3-n-octanoyl-2-DHA in the obtained structured lipid was 52.4%, and the proportion of n-octanoic acid in the triglyceride was 55.2%, labeled 10.

[0045] Comparative Example 2: Triglycerides and n-octanoic acid were used as substrates, without using a continuous flow enzyme-catalyzed reaction. The enzyme was added to the preheater and reacted directly with the substrate. Other synthesis experimental parameters were similar to those in Example 1. The resulting structured lipid had a mass percentage of 41.1% 1,3-octanoyl-2-DHA and a n-octanoic acid content of 43.7% in the triglycerides. Label 11.

[0046] Comparative Example 3: Commercially available algae oil (triglycerides with a 40% sn-2 DHA content) and n-octanoic acid were used as substrates, and other synthesis experimental parameters were referred to Example 1. The resulting structured lipid had a 1,3-n-octanoate-2-DHA mass percentage of 38.2% and a n-octanoic acid content of 56.4% in the triglycerides, designated as 12.

[0047] Comparative Example 4: n-octanoic acid, label number 13.

[0048] Comparative Example 5: triglyceride with a sn-2 DHA content of 70%, label number 14.

[0049] Test Example 1: Determination of toxic and side effects 1% of the product of the Example or Comparative Example was added to NGM culture medium containing 0.001% NP-40 in C. elegans. Stir at 50°C for 30 minutes to fully dissolve in NGM, then pour into a culture dish. After synchronizing the C. elegans, eggs were added to M9 buffer and incubated overnight at 20°C for 12 hours to hatch L1 larvae. Experimental intervention began with L1 larvae. A 5-day-old wild-type C. elegans sample was used as a healthy model. A C. elegans model of age-related sensory dysfunction (Alzheimer's disease) was purchased from the American Nematode Genetic Resource Center. Videos of the nematodes were captured using a stereo microscope, and body length was analyzed using Wormlab software.

[0050] The results are as follows Figure 4As shown, octanoic acid in Experiment 13 significantly reduced the nematode's body length compared to the blank control group, indicating that octanoic acid restricts the growth and development of C. elegans and has certain toxic side effects. However, products 1-12 obtained through the synthetic process did not significantly change the nematode's body length, demonstrating no significant toxic side effects.

[0051] Test Example 2: Measurement of activity to improve movement disorders Nematode culture procedures were performed as described in Experimental Example 1. Locomotor activity was measured as the number of wiggles per 30 seconds in M9 buffer. Each experiment was repeated three times, and the average value was taken. The above test was performed on products Nos. 1-9 prepared in Examples 1-5 and Nos. 10-14 determined in Comparative Examples 1-5.

[0052] The results are as follows Figure 5 As shown, compared to the products of Comparative Examples 10-14 and the blank control, the oscillation frequency of cognitively impaired C. elegans treated with the structural lipids No. 1-9 prepared by the present invention was significantly increased, demonstrating that the resulting structural lipids have excellent efficacy in improving movement disorders. Furthermore, the effects of all synthesized structural lipids were significantly higher than those of Comparative Examples 1-5 (Nos. 10-14), indicating a synergistic effect of the structural lipids. Furthermore, in Examples 1-5, the higher the mass percentage of 1,3-octanoic acid-2-DHA, the better the overall effect. Among them, structural lipid No. 1, which has the highest proportion of 1,3-octanoic acid-2-DHA (72.5%), has the best effect in improving movement disorders in nematodes, indicating that 1,3-octanoic acid-2-DHA-type structural lipids have a superior ability to enhance motor function.

[0053] Test Example 3: Measurement of activity to improve sensory impairment Refer to Experimental Example 1 for the nematode culture operation. Mark the center point of the 6 cm plate as point O, and mark points A and B on the left and right sides of point O at a distance of 2.5 cm from point O, and mark 0.5 cm in front of points A and B. Use the tip of a pipette to suck up about 50 nematodes and quickly drop them at point O, and record the total number of nematodes N. Place it in the incubator for about 10 minutes. After the nematodes are dispersed, drip isoamyl alcohol (attractant) and 1-octanol (repellent) at points A and B respectively. After adapting for a period of time at a relative humidity of 31% and 20°C, use a high-resolution camera to shoot for 10 seconds. Count the number of nematodes at the A and B ends after 1 hour. Calculate the chemotaxis index (CI): CI = (N A -N B ) / (N A +N B ), each group of experiments were repeated 3 times and the average value was taken.

[0054] where N A : the number of nematodes in isoamyl alcohol; N B: The number of nematodes at 1-octanol.

[0055] Figure 2 This is a trajectory diagram of the structural lipid of the present invention improving the movement and perception disorders of C. elegans, showing the effects of different embodiments and comparative examples on the movement and perception abilities of C. elegans. The line segments represent the distance the C. elegans crawls per unit time. Continuous and long line segments indicate good movement abilities of the C. elegans. A (attractant) and B (repellent) indicate that the C. elegans crawl toward point A rather than point B, indicating strong perception abilities. The statistical results are shown in Figure 1. Figure 6 As shown, compared to the control and model groups, the sensory ability of C. elegans was significantly improved after intervention with the structural lipids No. 1-9 prepared in Examples 1-5 of the present invention, indicating that the obtained structural lipids have the effect of improving sensory impairment. At the same time, in Examples 1-5, the higher the mass percentage of 1,3-octanoic acid-2-DHA, the better the effect, indicating that the structural lipid type 1,3-octanoic acid-2-DHA has a better ability to enhance perception.

[0056] It can be seen from Test Examples 2 and 3 that although the proportion of 1,3-octanoic acid-2-DHA in the structural lipids prepared in Comparative Example 1 is also relatively high, the effect of improving athletic ability and perception is still not significant. This is mainly because no nitrogen filling treatment was carried out during the reaction process, which may cause some DHA in the structural lipids to oxidize. DHA is a highly unsaturated fatty acid, and the multiple double bonds in its molecules are easily subjected to free radical chain reactions with oxygen, leading to oxidative degradation. After nitrogen filling, the reaction system is in an inert environment, which effectively avoids the oxidation of DHA. DHA is a highly unsaturated fatty acid that is easily affected by light, heat and oxygen and undergoes oxidative degradation, generating harmful substances, reducing nutritional value and possibly producing odor and toxicity. Nitrogen filling treatment reduces the oxygen partial pressure by replacing the oxygen in the reaction system, inhibits the occurrence of free radical chain reactions, and significantly improves the stability of DHA. This measure ensures the structural integrity of DHA during the reaction process and further improves the purity and quality of the final product.

[0057] Test Example 4: Sensory Evaluation of Structured Fat The sensory evaluation of each product was conducted using the QDA method. Thirty sensory evaluators were selected from faculty and students at the College of Food Science and Technology, Huazhong Agricultural University, based on their interests and descriptive abilities. A basic sensory ability test was administered in a standardized sensory analysis laboratory according to GB / T 16291.1-2012, "General Guidelines for the Selection, Training, and Management of Sensory Analysts - Part 1: Preferred Evaluators." A 15-person selection panel was selected, and each evaluator received 48 hours of sensory descriptive analysis training. Descriptors were determined according to the methods in GB / T 16861-1997, "Sensory Analysis - Identification and Selection of Descriptors for Establishing Sensory Profiles by Multivariate Analytical Methods." The 15 panelists brainstormed preliminary descriptive terms for each structural lipid's odor. The resulting descriptors were then screened through group discussion. Descriptors were rated for intensity using a 5-point scale. The scoring criteria are shown in Table 6. The geometric mean (M) was calculated using Equation (1). Descriptors were then ranked and deleted to determine the odor attributes. Finally, the odor attribute intensity of each example and comparative example product was evaluated using a 5-point scale. Each time, a 3-digit random number was used and presented randomly.

[0058] (1)

[0059] Where: F is the ratio of the number of times a descriptor is actually mentioned to the total number of times the descriptor may be mentioned; I is the ratio of the actual intensity of a descriptor given by the evaluation team to the maximum possible intensity of the descriptor.

[0060] Table 6. Rating criteria for aroma intensity of sensory attributes

[0061] The results are as follows Figure 7 The sensory evaluation scores indicated that octanoic acid (labeled 13) had a strong fusant flavor, while the triglyceride containing 70% sn-2 DHA (labeled 14) had a distinct fishy odor. The structured lipid synthesized using the present invention (labeled 1) scored significantly lower in oiliness, fusant flavor, and fishy odor, indicating that 1,3-octanoic acid-2-DHA triglyceride had better sensory acceptance.

[0062] The present invention constructs a 1,3-octanoic acid-2-DHA triglyceride structural lipid with precise molecular structure and significant functional synergy. DHA is located at the sn-2 position, and octanoic acid is distributed at the sn-1,3 positions, achieving dual functional synergy of neuroprotection and rapid energy supply. This structural lipid can be selectively hydrolyzed by pancreatic lipase in the body to release sn-2-DHA monoglyceride, significantly improving its absorption efficiency, and rapidly metabolizing octanoic acid to generate ketone bodies for energy supply, significantly alleviating the common brain energy metabolism imbalance problem in patients with neurodegenerative diseases. Compared with the problems of oxidative instability, strong irritation or toxic side effects when DHA or octanoic acid is used alone, this structural lipid exhibits good physiological safety and significant improvement in motor and sensory functions in animal models, reflecting obvious synergistic advantages.

[0063] This invention utilizes a continuous-flow immobilized enzyme catalysis process, combined with substrate structure optimization and precise control of reaction parameters, to successfully achieve the efficient synthesis of high-purity structural lipids. The product contains over 60% 1,3-octanoic acid-2-DHA, and the structural lipid purity reaches over 85% by HPLC. Compared with traditional static kettle enzymatic methods, this process shortens the reaction time to less than 2 hours, and the immobilized enzyme can be reused over 30 times. This process offers advantages such as high efficiency, environmental friendliness, controllability, and ease of scalability, making it suitable for the industrial-scale production of functional foods and special medical nutrition products.

[0064] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a structural lipid for improving cognitive impairment in the elderly, characterized by: The following steps are included: The immobilized lipase is filled into a continuous flow bio-enzyme catalytic reaction column and nitrogen-filled. Stirring and mixing triglyceride having a sn-2 DHA content of more than 65% and n-octanoic acid to obtain a reaction solution; The reaction solution is pumped into a continuous flow bio-enzyme catalytic reaction column to obtain a mixed lipid, which is then subjected to deacidification and dehydration treatment to obtain the structured lipid.

2. The method for preparing a structural lipid for improving cognitive impairment in the elderly according to claim 1, characterized in that: The immobilized lipase includes one or more of lipase Lipozyme TL IM, lipase R IM-03 or lipase IM-NE100.

3. The method for preparing a structured lipid for improving cognitive impairment in the elderly according to claim 1 or 2, characterized in that: The mixing is uniform and the mixing temperature is 30-60°C.

4. The method for preparing a structured lipid for improving cognitive impairment in the elderly according to claim 1 or 2, characterized in that: The mixing is uniform, the mixing temperature is 45-55° C., and the mixing time is 10-30 min.

5. The method for preparing a structured lipid for improving cognitive impairment in the elderly according to claim 1 or 2, characterized in that: The reaction liquid is pumped into a continuous flow bio-enzyme catalytic reaction column, and the temperature of the reaction column is 30-60°C.

6. The method for preparing a structured lipid for improving cognitive impairment in the elderly according to claim 1 or 2, characterized in that: The reaction liquid is pumped into a continuous flow bio-enzyme catalytic reaction column, and the temperature of the reaction column is 45-55°C.

7. The method for preparing a structured lipid for improving cognitive impairment in the elderly according to claim 1 or 2, characterized in that: The reaction solution is pumped into the continuous flow bio-enzyme catalytic reaction column at a flow rate of 0.25-1.0 mL / min.

8. The method for preparing a structured lipid for improving cognitive impairment in the elderly according to claim 1 or 2, characterized in that: The molar ratio of triglycerides with a sn-2 DHA mass content of more than 65% to n-octanoic acid is 1:2~6.

9. The structured lipid prepared by the method for preparing structured lipid for improving cognitive impairment in the elderly according to claim 1.

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