Extraction method of wild celery polysaccharide with antioxidant activity

Abstract

The invention discloses a method for extracting wild celery polysaccharide with antioxidant activity, which comprises the following steps: putting washed and drained wild celery into a drying oven at 60 DEG C, and drying to constant weight; adding ultrapure water in proportion after chopping, adjusting the extraction temperature by using a water bath kettle for extraction, and filtering to remove residues; placing the filtrate in an environment of 60 DEG C, and performing concentration operation by using a vacuum rotary evaporator until the volume of the filtrate is reduced to half of the initial volume; adding ethanol into the concentrated filtrate until the final concentration of the ethanol in the mixed solution reaches 75%; and standing and precipitating the mixed solution, collecting a precipitation product through centrifugal treatment after staying overnight, drying at normal temperature to remove residual ethanol, weighing, and removing the residual ethanol to obtain a product which is polysaccharide.

Description

Technical Field

[0001] The invention relates to the technical field of polysaccharide extraction, in particular to a method for extracting celery polysaccharide with antioxidant activity. Background Art

[0002] Wild celery, also known as short-fruited anise and large-leaf celery, is widely distributed in Northeast China, Japan, and the Korean Peninsula, with a particularly large distribution in the Changbai Mountain region. Its young stems and leaves, picked in spring, are tender, crisp, and fragrant. Wild celery is also an important traditional Chinese medicine, and its roots can be used to treat rheumatism, pain in the waist and knees, and other ailments.

[0003] Wild celery is rich in nutrients, containing a large amount of dietary fiber, vitamins, and minerals. From the perspective of active ingredients, wild celery contains flavonoids, volatile oils, polysaccharides, and other ingredients, which have significant antioxidant and anti-inflammatory physiological functions, playing a positive role in regulating immunity, protecting cardiovascular and cerebrovascular systems, and fighting fatigue.

[0004] Wild celery is rich in vitamins. 100g of fresh wild celery contains 205mg of methionine, 120mg of threonine, 31mg of isoleucine, 27mg of leucine, 38mg of phenylalanine, 17mg of lysine, 38mg of valine, 13mg of histidine, 44mg of alanine, 33mg of serine, and 6mg of glutamic acid. Diao Shaoqi et al. analyzed the nutritional composition of wild celery grown in the Changbai Mountains using atmospheric pressure drying and determined that its moisture content was 83.45%, lower than that of commonly cultivated vegetables such as Chinese cabbage and spinach. The ash content was 14.20%, the crude fiber content was 10.51%, and the crude protein content was 12.98%, all higher than that of Chinese cabbage. Wild celery is a naturally high-quality vegetable rich in crude protein and crude fiber.

[0005] Wild celery shoots are delicious, crisp, and fragrant, and can be used in salad dressings, stir-fries, pickles, juiced, and made into fillings. Wild celery primarily grows in the forests of the Changbai Mountains. Its natural, pollution-free, and fresh flavor makes it a popular "natural health food" in Northeast Asia. Because it's primarily harvested in spring and has a short shelf life, its development and utilization are crucial.

[0006] Wild celery, a unique wild resource from Changbai Mountain that can be used as both a medicine and a food, is rich in nutrients and boasts health benefits such as clearing heat and detoxification, fighting cancer, and acting as a diuretic and reducing swelling. However, its processing is primarily based on primary processes such as sun-drying and pickling, while further processing is still limited. To increase the added value of wild celery, this patent utilizes a hot water boiling method to extract the active polysaccharide from wild celery. Summary of the Invention

[0007] The purpose of the present invention is to provide a method for extracting mountain celery polysaccharides with antioxidant activity, so as to solve the problem in the prior art proposed in the above background technology that the extraction of polysaccharides is difficult due to the complex structure of polysaccharides and their frequent interaction with other components. In the process of extracting polysaccharides, it is particularly important to select a suitable extraction method to improve the extraction rate of polysaccharides, ensure the biological activity of polysaccharides and reduce production costs.

[0008] To achieve the above object, the present invention provides the following technical solution: a method for extracting celery polysaccharides with antioxidant activity, characterized in that it comprises the following steps:

[0009] Step 1: Wash and drain the wild celery and place it in an oven to dry until constant weight;

[0010] Step 2: After chopping, add ultrapure water in proportion, use a water bath to adjust the extraction temperature, and filter to remove the residue;

[0011] Step 3: Place the filtrate in a 60°C environment and use a vacuum rotary evaporator to concentrate the filtrate until the volume is reduced to half of the initial volume;

[0012] Step 4: Add ethanol to the concentrated filtrate to make the final concentration of ethanol in the mixed solution reach 75%;

[0013] Step 5: The mixed solution is allowed to settle overnight, and then the precipitated product is collected by centrifugation, dried at room temperature to remove residual ethanol and weighed. The product obtained by removing the residual ethanol is a polysaccharide.

[0014] A more preferred solution is to place the washed and drained mountain celery in a 60°C oven and dry it to constant weight.

[0015] Compared with the prior art, the present invention obtains through experiments the optimal process parameters of celery polysaccharide as feed-liquid ratio 1:21, extraction temperature 92° C., and extraction time 4 h. Under the optimal conditions, the maximum extraction rate is 9.27±0.25%. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a proportional diagram showing the effect of the material-liquid ratio on the extraction rate of the celery polysaccharide of the present invention;

[0017] Figure 2 This is a proportional diagram showing the effect of the extraction temperature on the extraction rate of the celery polysaccharide of the present invention;

[0018] Figure 3 This is a proportional diagram showing the effect of the extraction time on the extraction rate of the celery polysaccharide of the present invention;

[0019] Figure 4 This is a diagram showing the scavenging effects of WOSP, WOSP-N, and WOSP-A of the present invention on DPPH free radicals;

[0020] Figure 5 This is a diagram showing the scavenging effects of WOSP, WOSP-N, and WOSP-A of the present invention on superoxide anions;

[0021] Figure 6 This is a diagram showing the scavenging effects of WOSP, WOSP-N, and WOSP-A of the present invention on hydroxyl radicals;

[0022] Figure 7 This is a diagram showing the Fe3+ reduction ability of WOSP, WOSP-N, and WOSP-A of the present invention. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0024] A method for extracting celery polysaccharide with antioxidant activity:

[0025] Step 1: Wash and drain the wild celery and place it in a 60°C oven to dry to constant weight (m1);

[0026] Step 2: After chopping, add ultrapure water in proportion, use a water bath to adjust the extraction temperature, and filter to remove the residue;

[0027] Step 3: Place the filtrate in a 60°C environment and use a vacuum rotary evaporator to concentrate the filtrate until the volume is reduced to half of the initial volume;

[0028] Step 4: Add ethanol to the concentrated filtrate to make the final concentration of ethanol in the mixed solution reach 75%;

[0029] Step 5: The mixed solution is allowed to settle overnight, and then the precipitated product is collected by centrifugation, dried at room temperature to remove residual ethanol and weighed (m2). The product obtained by removing the residual ethanol is a polysaccharide.

[0030] The extraction rate is calculated according to the following formula

[0031]

[0032] Phenol-sulfuric acid spectrophotometry was used to quantitatively analyze polysaccharides from Cephalotaxus chinensis. Accurately weigh 5 mg of standard glucose (Glc) and prepare it with distilled water to a concentration of 0.1 mg / mL. The standard glucose solution was then diluted according to the total sugar content standard curve configuration table. 500 μL of 6% phenol solution and 2.5 mL of concentrated sulfuric acid were then added. The absorbance was measured at a wavelength of 490 nm. A standard curve was plotted with the mass concentration of glucose (Glc) as the horizontal axis and the corresponding absorbance as the vertical axis.

[0033] Use a high-precision balance to weigh 1 mg of polysaccharide sample and place it in a suitable container. Add 10 mL of distilled water to the container and stir or shake thoroughly to completely dissolve the polysaccharide sample to prepare a polysaccharide solution with a mass concentration of 0.1 mg / mL. Use a pipette to accurately measure 500 μL of 6% phenol solution and slowly add it to the above polysaccharide solution. Then accurately measure 2.5 mL of concentrated sulfuric acid and slowly add it along the wall of the container. Calculate the total sugar content according to the standard curve equation.

[0034] Preparation of standard curve of total sugar content

[0035]

[0036] At the same time, the applicant also conducted experiments to determine the influence of the material-liquid ratio on the extraction rate of celery polysaccharide. The effects of different material-liquid ratios on the extraction rate of celery polysaccharide were as follows: Figure 1 As shown. When the solid-liquid ratio is between 1:5 and 1:25, the extraction rate of celery polysaccharides shows a trend of first increasing and then decreasing. When the solid-liquid ratio is 1:20, the extraction rate reaches a maximum of 9.43±0.60%. However, when the solid-liquid ratio continues to increase, the polysaccharide extraction rate decreases slightly. This is because the dissolution of celery polysaccharides tends to be stable and balanced, but it may cause losses during the cooking process and more solvent will also increase the subsequent concentration cost. The experimental results show that the extraction rate of celery polysaccharides reaches the maximum when the solid-liquid ratio is 1:20, so the three levels of 1:15, 1:20 and 1:25 are selected for the response surface experiment.

[0037] The present applicant also conducted experiments to determine the effect of extraction temperature on the extraction rate of celery polysaccharide. Under the experimental conditions of a fixed solid-liquid ratio of 1:20 and an extraction time of 4 hours, the effects of different extraction temperatures on the extraction rate of celery polysaccharide are shown in the figure. Figure 2 Among. From Figure 2The extraction rate of celery polysaccharides increased with increasing extraction temperature. When the extraction temperature reached 90°C, the growth trend in the extraction rate flattened and reached equilibrium, reaching a polysaccharide extraction rate of 7.01±0.44%. At 100°C, the extraction rate was 7.17±0.64%. Since there was no significant difference in the extraction rates between the two, 90°C was the optimal extraction temperature for energy conservation. Appropriately increasing the temperature can promote irreversible destruction of the cellulose and hemicellulose structures of plant cell walls and increase cell permeability. High temperatures can also reduce solution viscosity and promote the dissolution of polysaccharide molecules. Experimental results showed that the optimal extraction rate was 7.01±0.44% at 90°C. Therefore, three extraction temperatures (80, 90, and 100°C) were selected for the response surface experiment.

[0038] The applicant also conducted experiments to determine the effect of extraction time on the extraction rate of celery polysaccharide. Under the conditions of solid-liquid ratio of 1:20 and extraction temperature of 90°C, the effects of different extraction times on the extraction rate of celery polysaccharide are as follows: Figure 3 As shown in the figure, the extraction rate of celery polysaccharides increases with extraction time, reaching a plateau after extraction time exceeds 4 hours. Since there is no significant difference in extraction rate after extraction time exceeding 4 hours, 4 hours was selected as the optimal extraction time based on time cost considerations. The experimental results showed that the optimal extraction time was 4 hours, with an extraction rate of 6.67±0.61%. Therefore, 60, 70, and 80 minutes were selected as the time parameter levels for the response surface optimization experiment.

[0039] In the analysis experiment of the DPPH scavenging ability of celery polysaccharides, ascorbic acid was used as a positive control substance to study the DPPH free radical scavenging ability of three celery polysaccharides. The three celery polysaccharides were WOSP, WOSP-N, and WOSP-A. The results are as follows Figure 4 As shown in Figure 2, as the concentrations of the three celery polysaccharides gradually increased, their scavenging rates of DPPH free radicals also showed a corresponding upward trend. When the concentration was 10 mg / mL, the DPPH scavenging rates of WOSP, WOSP-N and WOSP-A were 93.17±3.12%, 45.48±1.10% and 91.35±1.68%, respectively. Figure 4 It can be seen that WOSP and WOSP-N have better ability to scavenge DPPH.

[0040] In the superoxide anion scavenging ability analysis experiment of celery polysaccharides, ascorbic acid was used as a positive control to study the superoxide anion scavenging ability of three celery polysaccharides. Figure 5As shown, as the concentration of the three celery polysaccharides gradually increased, their superoxide anion scavenging abilities also increased accordingly. When the polysaccharide concentration reached 10 mg / mL, the superoxide anion scavenging rates of WOSP, WOSP-N, and WOSP-A varied: 71.36±1.14% for WOSP, 70.81±1.20% for WOSP-N, and 43.72±1.68% for WOSP-A. These results indicate that WOSP and WOSP-N possess superior superoxide anion scavenging abilities.

[0041] In the scavenging hydroxyl radical ability analysis experiment of the three celery polysaccharides, the scavenging ability of the three celery polysaccharides on hydroxyl free radicals was analyzed with ascorbic acid as the positive control. Figure 6 As shown in the results, the scavenging ability of the three celery polysaccharides on hydroxyl radicals increased with the increase of polysaccharide concentration. When the concentration was 10 mg / mL, the superoxide anion scavenging rates of WOSP, WOSP-N and WOSP-A were 53.15±2.64%, 34.88±1.55% and 50.53±0.68%, respectively. The experimental results showed that WOSP and WOSP-N had better hydroxyl free radical scavenging ability.

[0042] In the Fe3+ reducing ability analysis experiment of the three celery polysaccharides, the ferric iron reducing ability of the three celery polysaccharides was analyzed with ascorbic acid as the positive control. Figure 7 As shown in the figure, with the increase of polysaccharide concentration, the effects of three kinds of celery polysaccharides on Fe 3+ The reducing ability increased accordingly. When the concentration was 10 mg / mL, the absorption values of WOSP, WOSP-N and WOSP-A at 700 nm were 1.89±0.035%, 0.95±0.06% and 0.92±0.01%, respectively. The experimental results showed that WOSP has better Fe 3+ Restoration ability.

[0043] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for extracting celery polysaccharide with antioxidant activity, characterized in that: The following steps are involved: Step 1: Wash and drain the wild celery and place it in an oven to dry until constant weight; Step 2: After chopping, add ultrapure water in proportion, use a water bath to adjust the extraction temperature, and filter to remove the residue; Step 3: Place the filtrate in a 60°C environment and use a vacuum rotary evaporator to concentrate the filtrate until the volume is reduced to half of the initial volume; Step 4: Add ethanol to the concentrated filtrate to make the final concentration of ethanol in the mixed solution reach 75%; Step 5: The mixed solution is allowed to settle overnight, and then the precipitated product is collected by centrifugation, dried at room temperature to remove residual ethanol and weighed. The product obtained by removing the residual ethanol is a polysaccharide.

2. The method for extracting celery polysaccharide with antioxidant activity according to claim 1, characterized in that: Place the washed and drained wild celery in a 60°C oven and dry to constant weight.

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