A seaweed active ingredient and gradient extraction process thereof

Abstract

The present application discloses a seaweed active ingredient and a gradient extraction process thereof, and belongs to the field of seaweed extraction technology. The gradient extraction process of the seaweed active ingredient comprises the following steps: harvesting freshly salvaged seaweed, washing impurities on its surface with seawater, then slicing and adding sodium carbonate solution to stir, to obtain seaweed slurry; adding ethanol thereto and stirring, and obtaining a precipitate and an ethanol extract 1 after extrusion; adding ethanol to the precipitate and stirring, and then centrifuging to obtain a crude alginate extract and a supernatant 1, which is evaporated to recover ethanol and obtain a crude fucoidan extract; adding water to the ethanol extract 1 and stirring, and then centrifuging to obtain a crude fucoxanthin extract and a supernatant 2, which is evaporated to recover ethanol and obtain a crude brown algae polyphenol extract. The gradient extraction process can obtain crude extracts of multiple active ingredients at the same time, and does not require the use of a large amount of fresh water resources and toxic reagents, does not generate waste, is simple to operate, and has low cost, which is conducive to promotion and application.

Description

Technical Field

[0001] The present application relates to a seaweed active ingredient and a gradient extraction process thereof, belonging to the technical field of seaweed extraction. Background Art

[0002] The ocean area accounts for 71% of the world's area. Seaweed is an important part of marine biological resources and is closely related to human life and economic development. Chile, China and Norway are the world's major producers of wild seaweed, with an annual output accounting for more than 60% of the world. Compared with wild seaweed resources, the global seaweed farming volume can reach 35 million tons (fresh weight). Among them, China has a long coastline and a large offshore area. It is one of the world's largest seaweed farming countries. In recent years, the production of seaweed farming has continued to rise, accounting for more than 58% of the world's total, and the seaweed species are very rich. The cultivated seaweed mainly includes kelp, wakame, laver, seaweed, eucheuma, and gracilaria. Among them, kelp has the highest output. Kelp and other brown algae contain rich active substances, such as alginate, fucoidan, fucoxanthin, brown algae polyphenols, dietary fiber, etc., all of which have unique physiological activities, such as regulating blood lipids, lowering blood sugar, lowering blood pressure, anti-coagulation, anti-tumor, anti-oxidation, immune enhancement, etc., and are widely used in food, health products, medicine, cosmetics, medical materials and other fields.

[0003] Alginate is the earliest and currently the largest seaweed processed product. The traditional processing technology still faces the limitations of complicated process, high water consumption, high energy consumption and many wastes. Especially after the extraction of alginate, the remaining residues of the extraction still contain active substances such as fucoidan, fucoxanthin, and brown algae polyphenols, which are discarded, wasting resources and polluting the environment. Fucoidan is a water-soluble polysaccharide. Regardless of whether it is extracted by physical or chemical methods, the extract includes all types of water-soluble components, and the large amount of water used in the extraction process leads to a large amount of waste liquid, resulting in a waste of resources. Fucoxanthin and brown algae polyphenols are fat-soluble components, accounting for about 1%-4% of the dry weight of seaweed. A large amount of organic solvents are required for repeated extraction during the extraction process, which is easy to cause environmental pollution, high cost, and difficult to scale up the process. Due to the different processing technology of each active substance, the cost of recovering other components in the residue after extracting an active substance is huge, resulting in a waste of seaweed resources.

[0004] Therefore, how to fully extract the active ingredients in seaweed directly at sea, with a simple and easy extraction method and environmentally friendly extraction agents, is a technical problem that needs to be urgently solved by technicians in this field. Summary of the invention

[0005] In order to solve the above problems, a seaweed active ingredient and a gradient extraction process thereof are provided, which can obtain crude extracts of multiple active ingredients at the same time, without using a large amount of fresh water resources and toxic reagents, without generating waste, with simple operation and low cost, which is conducive to promotion and application.

[0006] The present invention is achieved through the following technical solutions:

[0007] A gradient extraction process for seaweed active ingredients comprises the following steps:

[0008] (1) harvesting freshly salvaged seaweed, washing the impurities on the surface with seawater, then slicing the seaweed, adding a sodium carbonate solution with a mass fraction of 2-12%, and stirring evenly to obtain seaweed slurry;

[0009] (2) adding 90-100% ethanol to the seaweed slurry and stirring the mixture thoroughly, and squeezing the mixture to obtain a precipitate 1 and an ethanol extract 1;

[0010] (3) adding 30-40% ethanol to the precipitate 1, stirring thoroughly and centrifuging to obtain a precipitate 2 and a supernatant 1, drying the precipitate 2 to obtain a crude alginate extract, and performing rotary evaporation on the supernatant 1 to recover ethanol. The precipitate 3 obtained after drying is a crude fucoidan extract;

[0011] (4) adding water to the ethanol extract 1 and stirring until the ethanol concentration reaches 60-70%, and then centrifuging to obtain a precipitate 4 and a supernatant 2. The precipitate 4 is dried to obtain a crude fucoxanthin extract. The supernatant 2 is subjected to rotary evaporation to recover ethanol. The obtained precipitate 5 is dried to obtain a crude brown algae polyphenol extract.

[0012] Optionally, in step (1), the seaweed is selected from one or more of giant kelp, sargassum, ascophyllum, kelp, undatus and fucus.

[0013] Optionally, in step (1), the water content of the seaweed is above 90%.

[0014] Optionally, in step (1), the length of the seaweed after slicing does not exceed 10 cm.

[0015] Optionally, in step (1), the stirring temperature is 80-90° C., the stirring speed is 300-500 r / min, and the stirring time is 2-6 h.

[0016] Optionally, in step (2) and step (3), the material-liquid ratio is 1:10-20.

[0017] Optionally, in step (2), step (3) and step (4), the stirring temperature is 50-60° C., the stirring speed is 300-500 r / min, and the stirring time is 2-6 h.

[0018] Optionally, in step (3) and step (4), the centrifugation temperature is 0-6°C, the centrifugation speed is 1000-2000 r / min, and the centrifugation time is 5-20 min.

[0019] Optionally, in step (3) and step (4), the drying temperature is 40-80°C.

[0020] According to another aspect of the present application, there is provided a seaweed active ingredient obtained by any of the above-mentioned gradient extraction processes for the seaweed active ingredient.

[0021] The beneficial effects of this application include but are not limited to:

[0022] 1. The gradient extraction process of the active ingredients of seaweed of the present application can be implemented at sea. Since there are many areas in the world with rich wild seaweed resources, but they are difficult to harvest and transport, such as the Falkland Islands, the climate is cold and humid, with an average annual temperature of 5.6°C, an average annual precipitation of 625 mm, and up to 250 days of rain and snow in a year. The cool climate characteristics make it impossible to dry and transport the seaweed after harvesting. By using the gradient extraction process of the active ingredients of seaweed of the present application, crude alginate extracts, crude fucoidan extracts, crude fucoxanthin extracts and crude brown algae polyphenol extracts can be obtained directly at sea, and then the crude products can be transported to the onshore processing plant for purification and refining to obtain the desired products.

[0023] 2. The gradient extraction process of seaweed active ingredients in the present application can develop and utilize the "red tide" Sargassum, an algal bloom resource that periodically erupts at sea. For example, at the peak of the Sargassum outbreak in 2019, 20 million tons of Sargassum stretched over 8,000 kilometers in the Gulf of Mexico and spanned 20 million square kilometers of sea area, forming the Sargasso Sea in the Atlantic Ocean, causing huge economic losses to the marine ecosystem, coastal tourism industry and fisheries. It is very costly to remove Sargassum from the ocean and it does not solve the fundamental problem. However, the offshore processing of the algal bloom can not only extract the active ingredients therein for the development of food, seaweed fertilizer and other products, improve resource utilization, but also protect the ecological balance of the ocean, turn "waste" into treasure, and reduce cleaning costs.

[0024] 3. The gradient extraction process for active ingredients of seaweed of the present application can use seawater for extraction when operated at sea, and at the same time recycle processing aids to achieve deep processing and comprehensive utilization of seaweed resources, which can not only make full use of the waste generated in the old process and reduce environmental pollution, but also save water resources and significantly reduce the storage and transportation costs of fresh algae and the extraction costs of natural seaweed products; then the crude active ingredients obtained are transported to the shore for intensive processing, thereby increasing the added value of the seaweed; therefore, the gradient extraction process for active ingredients of seaweed of the present application can achieve full utilization of my country's abundant seaweed resources, create greater economic benefits, and further promote the development and growth of my country's seaweed bio-industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0026] Figure 1 This is a flow chart of the gradient extraction process of seaweed active ingredients involved in the embodiments of the present application. DETAILED DESCRIPTION

[0027] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0028] If no specific conditions are specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The raw materials or instruments used, if no manufacturer is specified, are all conventional products that can be purchased commercially.

[0029] Example 1

[0030] refer to Figure 1 , a gradient extraction process of seaweed active ingredients, comprising the following steps:

[0031] (1) taking 5 kg of freshly salvaged kelp (with a water content of 93%), washing the impurities on its surface with seawater, then slicing the kelp into 5.5 cm long slices, adding a 10% sodium carbonate solution by mass, and stirring at 90° C. and 500 r / min for 2 h to obtain kelp slurry;

[0032] (2) adding 10 times the mass of 100% ethanol to the kelp slurry, stirring at 60° C. and 500 r / min for 3 h, and extruding the resulting mixture to obtain a precipitate 1 and an ethanol extract 1;

[0033] (3) adding 10 times the mass of 40% ethanol to the precipitate 1, stirring at 500 r / min for 4 h at 60°C, and then centrifuging at 1500 r / min for 10 min at 4°C to obtain a precipitate 2 and a supernatant 1, drying the precipitate 2 at 60°C to obtain a crude alginate extract, and performing rotary evaporation on the supernatant 1 to recover ethanol, and drying the obtained precipitate 3 at 60°C to obtain a crude fucoidan extract;

[0034] (4) Add water to the ethanol extract 1 until the ethanol concentration is 70%, and stir at 500 r / min at 60°C for 4 h, and then centrifuge at 1500 r / min at 4°C for 15 min to obtain a precipitate 4 and a supernatant 2. Dry the precipitate 4 at 60°C to obtain a crude fucoxanthin extract, and rotary evaporate the supernatant 2 to recover ethanol. The obtained precipitate 5 is dried at 60°C to obtain a crude brown algae polyphenol extract.

[0035] Example 2

[0036] refer to Figure 1 , a gradient extraction process of seaweed active ingredients, comprising the following steps:

[0037] (1) taking 5 kg of freshly salvaged kelp (with a water content of 93%), washing the impurities on its surface with seawater, then slicing the kelp into 5.5 cm long slices, adding a 10% sodium carbonate solution by mass, and stirring at 90° C. and 500 r / min for 2 h to obtain kelp slurry;

[0038] (2) adding 10 times the mass of 95% ethanol to the kelp slurry, and stirring at 60° C. and 500 r / min for 4 h, and extruding the resulting mixture to obtain a precipitate 1 and an ethanol extract 1;

[0039] (3) adding 10 times the mass of 35% ethanol to the precipitate 1, stirring at 500 r / min for 4 h at 60°C, and then centrifuging at 1500 r / min for 10 min at 0°C to obtain a precipitate 2 and a supernatant 1, drying the precipitate 2 at 60°C to obtain a crude alginate extract, and performing rotary evaporation on the supernatant 1 to recover ethanol, and drying the obtained precipitate 3 at 60°C to obtain a crude fucoidan extract;

[0040] (4) Add water to the ethanol extract 1 until the ethanol concentration is 70%, and stir at 60°C at 500 r / min for 4 h, then centrifuge at 0°C at 1500 r / min for 15 min to obtain a precipitate 4 and a supernatant 2. Dry the precipitate 4 at 60°C to obtain a crude fucoxanthin extract, and rotary evaporate the supernatant 2 to recover ethanol. Dry the obtained precipitate 5 at 60°C to obtain a crude brown algae polyphenol extract.

[0041] Example 3

[0042] refer to Figure 1 , a gradient extraction process of seaweed active ingredients, comprising the following steps:

[0043] (1) 5 kg of freshly salvaged Sargassum (water content of 90%) was taken, and impurities on the surface were washed off with seawater, and then the Sargassum was sliced ​​into 3.5 cm in length, and a sodium carbonate solution with a mass fraction of 10% was added, and the mixture was stirred at 90° C. and a speed of 500 r / min for 2 h to obtain Sargassum slurry;

[0044] (2) adding 10 times the mass of 95% ethanol to the Sargassum slurry, and stirring at 60° C. and 500 r / min for 4 h, and extruding the resulting mixture to obtain a precipitate 1 and an ethanol extract 1;

[0045] (3) adding 10 times the mass of 35% ethanol to the precipitate 1, stirring at 500 r / min for 4 h at 60°C, and then centrifuging at 1500 r / min for 10 min at 4°C to obtain a precipitate 2 and a supernatant 1, drying the precipitate 2 at 60°C to obtain a crude alginate extract, and performing rotary evaporation on the supernatant 1 to recover ethanol, and drying the obtained precipitate 3 at 60°C to obtain a crude fucoidan extract;

[0046] (4) Add water to the ethanol extract 1 until the ethanol concentration is 70%, and stir at 500 r / min at 60°C for 4 h, and then centrifuge at 1500 r / min at 4°C for 15 min to obtain a precipitate 4 and a supernatant 2. Dry the precipitate 4 at 60°C to obtain a crude fucoxanthin extract, and rotary evaporate the supernatant 2 to recover ethanol. The obtained precipitate 5 is dried at 60°C to obtain a crude brown algae polyphenol extract.

[0047] Comparative Example 1

[0048] A process for extracting fucoidan comprises the following steps:

[0049] The dried kelp was crushed and treated with anhydrous ethanol, and the filter residue was treated with acetone to obtain defatted kelp residue, which was then treated with hot water. The treatment conditions were: extraction time 5h, extraction temperature 70°C, and liquid-to-solid ratio of 40:1.

[0050] Under this condition, the crude extraction rate of fucoidan was 9.29% and the fucoidan content was 14.33%.

[0051] For details, see the Chinese academic paper: Wu Wenjie, Fan Wenle, Yi Shouzhi. Research on comprehensive utilization of kelp [J]. Food Science and Technology, 2006, 31(1):4.

[0052] Comparative Example 2

[0053] A process for extracting fucoidan and fucoxanthin comprises the following steps:

[0054] In the first step, fucoxanthin and fucoxanthin were extracted from kelp with a mixed solvent. The optimal extraction process of fucoxanthin was: extract twice with 40 times the volume of a 4:1:1 mixed solvent of anhydrous ethanol, acetone and petroleum ether at 40°C, each time for 1 hour. After the extracted extract was saponified, fucoxanthin and fucoxanthin were separated and purified by silica gel column chromatography, and finally high-purity products of fucoxanthin and fucoxanthin were obtained.

[0055] In the second step, mannitol was extracted from the kelp residue obtained after extracting fucoxanthin and fucoxanthin. 85% ethanol, which was 10 times the weight of the kelp, was added to the kelp residue and extracted at 90°C for 1 hour. The total extraction rate of the two extractions could reach 9-10%. The extracted mannitol was purified by recrystallization, and the purity after purification was 97.3%.

[0056] The third step is to extract fucoidan from the kelp waste residue obtained after the mannitol is extracted. Add 10 times the weight of the kelp extraction solvent to the 40-mesh kelp powder and extract at 60°C for 1.5 hours.

[0057] According to the above process route, experiments were conducted and 3.29g of fucoidan (34% purity), 9-10g of mannitol (more than 95% purity), 0.06g of fucoxanthin (91.6% purity) and 0.26g of fucoxanthin (92.1% purity) were extracted from every 100g of kelp.

[0058] For details, please see the Chinese academic paper: Research on the comprehensive extraction and purification process of fucoxanthin, fucoxanthin, mannitol and fucoidan from kelp [D]. Northwest University.

[0059] Comparative Example 3

[0060] The process flow of comprehensive extraction and utilization of the main active ingredients of kelp includes:

[0061] After the kelp is washed to remove the salt, it is soaked in pH 3.0 citric acid water overnight, and 10 times the amount of pH 2.0 acid aqueous solution is added, and the filtrate and residue are extracted in a water bath at 95°C for 2.5 hours, three times, and the filtrate and residue are collected separately. The filtrate is subjected to enzymatic deproteinization, AB-8 resin decolorization, LSA-AS resin dearsenicization, ethanol graded alcohol precipitation, and DEAE-Cellulose column chromatography purification to prepare fucoidan; and the residue is dried in the shade, and then extracted with 12 times acetone solution for 2.5 hours, extracted twice, and dearsenicized by LSA-AS resin and purified by silica gel column chromatography, respectively, to prepare fucoxanthin at the same time. (Obtained by integrating the extraction and purification routes of the two components of fucoxanthin and fucoidan and the dearsenicization process)

[0062] The experimental verification results are as follows: the extraction rate of fucoxanthin is 0.074%, the fucoidan is 3.94%, 0.30g of fucoxanthin can be extracted from every 100g of kelp, the HPLC content is 24.6%, and the arsenic content is 0.7ppm. At the same time, 4.48g of crude fucoidan can be extracted from every 100g of kelp, of which the total polysaccharide content is 87.5%, the organic sulfate is 18.9%, the fucose is 20.7%, the protein is 2.9%, and the arsenic content is 0.9ppm.

[0063] For details, please see the Chinese academic paper: Zhou Weisong. Research on comprehensive extraction and purification of fucoxanthin and fucoidan from kelp [D]. Zhejiang University, 2014.

[0064] Comparative Example 4

[0065] A process for extracting brown algae polyphenols comprises the following steps:

[0066] After the fresh Sargassum samples were collected, they were rinsed with fresh water and frozen for storage. After thawing, they were crushed with a tissue crusher. 20 g of Sargassum homogenate was accurately weighed, put into a four-necked round-bottom flask, added with 70% ethanol, stirred evenly with a glass rod, put into a microwave rapid reaction system, controlled the power to 700 W, and extracted for 5 minutes. Finally, the filter was filtered with a Buchner funnel, and the residue was repeatedly extracted once. The two extracts were combined, and the ethanol was removed by vacuum rotary evaporation to obtain the Sargassum polyphenol crude extract.

[0067] Microwave power and extraction temperature have a significant impact on the polyphenol yield. The optimal extraction process conditions are: ethanol volume fraction 80%, microwave power 600W, extraction temperature 70℃, solid-liquid ratio 1:10g / mL, and extraction time 4min. Under this condition, the yield of polyphenols in Sargassum fusiformis can reach 2.33%.

[0068] For details, please see the Chinese academic paper: Wang Junhong, Gao Haiyan, Ge Linmei, et al. Study on the process of microwave-assisted extraction of polyphenols from Sargassum fusiformis [J]. Journal of Zhejiang Agricultural Sciences, 2013, 25(6): 1368-1372.

[0069] After testing, the yields of crude alginate extract, crude fucoidan extract, crude fucoxanthin extract and crude brown algae polyphenol extract obtained by the extraction processes of Examples 1-3 and Comparative Examples 1-4, as well as the contents of alginate, fucose, fucoxanthin and brown algae polyphenol therein are shown in Table 1 below.

[0070] Table 1

[0071]

[0072]

[0073] As can be seen from Table 1, the extraction process of Comparative Example 1 can only obtain alginate and fucoidan at the same time, the extraction processes of Comparative Examples 2 and 3 can only obtain fucoidan and fucoxanthin at the same time, and the extraction process of Comparative Example 4 can only obtain brown algae polyphenols. However, the gradient extraction process of seaweed active ingredients of Examples 1-3 can simultaneously obtain high-yield alginate crude extract, fucoidan crude extract, fucoxanthin crude extract, and brown algae polyphenol crude extract, and the alginate content, fucose content, fucoxanthin content, and brown algae polyphenol content are also high, which can meet the actual production needs. At the same time, the process is simple and can be directly operated at sea, without using a large amount of fresh water resources and toxic reagents, and does not generate waste. It is not only environmentally friendly, but also low in cost, and therefore has broad application prospects.

[0074] The above is only the embodiment of the present application, and the protection scope of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the technical ideas and principles of the present application should be included in the protection scope of the present application.

Claims

1. A gradient extraction process for seaweed active ingredients, characterized in that: The following steps are involved: (1) taking 5 kg of freshly salvaged kelp with a water content of 93%, washing the impurities on its surface with seawater, then slicing the kelp into 5.5 cm long slices, adding a 10% sodium carbonate solution by mass, and stirring at 90° C. and 500 r / min for 2 h to obtain kelp slurry; (2) adding 10 times the mass of 100% ethanol to the kelp slurry, stirring at 60° C. and 500 r / min for 3 h, and extruding the resulting mixture to obtain a precipitate 1 and an ethanol extract 1; (3) adding 10 times the mass of 40% ethanol to the precipitate 1, stirring at 500 r / min for 4 h at 60°C, and then centrifuging at 1500 r / min for 10 min at 4°C to obtain a precipitate 2 and a supernatant 1, drying the precipitate 2 at 60°C to obtain a crude alginate extract, and performing rotary evaporation on the supernatant 1 to recover ethanol, and drying the obtained precipitate 3 at 60°C to obtain a crude fucoidan extract; (4) Add water to the ethanol extract 1 until the ethanol concentration is 70%, and stir at 500 r / min at 60°C for 4 h, and then centrifuge at 1500 r / min at 4°C for 15 min to obtain a precipitate 4 and a supernatant 2. Dry the precipitate 4 at 60°C to obtain a crude fucoxanthin extract, and rotary evaporate the supernatant 2 to recover ethanol. The obtained precipitate 5 is dried at 60°C to obtain a crude brown algae polyphenol extract.

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