KR101115357B1 - Methods for extracting crude oil from wet microalgae - Google Patents

Abstract

PURPOSE: A method for extracting crude oil from wet microalgae is provided to yield the crude oil more quickly and economically than existing dry-extraction method, and to fundamentally prevent the modification of functional material in microalgae. CONSTITUTION: A method for extracting crude oil from wet microalgae comprises a step of physically pulverizing wet microalgae, and a step of extracting crude oil from microalgae by using the extraction solvent. The microalgae are Schizochytrium genera, Thraustochytrium genera, Japonochytrium genera, UIkenia genera, Crypthecodinium genera, or Haliphthoros genera. In the pulverizing step, the microalgae are pulverized by using a bead mill, a French presser, or a homogenizer.

Description

Method for Extracting Crude Oil from Wet Microalgae {Methods for Extracting Crude Oil from Wet Microalgae}

The present invention relates to a method for extracting crude oil from wet algae.

Microalgae are an excellent resource for the production of polyunsaturated fatty acids, which can thrive in the food chain by converting carbohydrates into useful fats and oils in a sea-blocked, organic-rich environment. Passing on. However, microalgae-derived omega-3 fats are in the spotlight, replacing fish-derived omega-3 fats, which are easily exposed to problems such as heavy metals, and the market is also increasing. Factors supporting this trend include high prices of microorganism-derived polyunsaturated fatty acids, ease of supply of highly unsaturated fatty acids, superior oxidative stability to fish oil, sustainability of production, new production of biochemical metabolic pathways and genetic knowledge. It provides a system and a means of product development.

As a source of oil, microorganisms are less well known than plants and animals. The production of microbial oil or single-cell oil (SCO) is a relatively new concept and was first proposed in the 20th century. Although vegetable oils and animal fats are relatively inexpensive, the focus is on the fact that microbial oil production is a high value-added product that cannot be mass produced by plants in the future.

The omega-3 series polyunsaturated fatty acids, especially docosahexaenoic acid (Docosahexaenoic acid, DHA) is produced in conjunction with using a large amount of micro-organisms present, the teurawooseu talkie yttrium (Thraustochytrium) type of marine microalgae in and rest Jockey A method for preparing omega-3 unsaturated fatty acids by the genus Microorganism of Schizochytrium has been disclosed by Ellenbogen et al . (Ellenbogen B. B et al , Comparative Biochemistry and Physiology , 29: 805-811 (1969)).

Looking at the industrial market, matek (Martek) buy rest Jockey Jockey Relax Inn Atrium Atrium spp sp. ATCC 20888 (Schizochytrium sp. ATCC 20888 ) and Shh Jockey atrium sp. A method for preparing omega-3 unsaturated fatty acids using ATCC 20889 ( Schizochytrium sp. ATCC 20888) has been disclosed (US Pat. No. 5,130,242 and US Pat. No. 5,340,742). In addition, Suntory (Suntory) live docosahexaenoic acid is a productivity report the rest Jockey atrium Lima City num SR21 (Schizochytrium limacinum SR21) with excellent microbiological Bar (Japanese Unexamined Patent Publication No. 1997-000284 and US Patent No. 6,582,941).

Polyunsaturated production from microalgae usually includes fermentation, recovery, and drying processes. After drying, polyunsaturated fatty acids derived from microalgae are extracted through intracellular lipid extraction using nonpolar solvents such as hexane. Get Extraction method of oil included in microalgae can be divided into chemical and mechanical methods. In detail, oil extraction can be divided into solvent-free extraction and solvent extraction depending on whether solvent is used. In the case of solvent-free extraction, an oil-free method is obtained by not using or minimizing an organic solvent such as hexane, such as enzymatic decomposition reaction and heat treatment. In the case of solvent-free extraction, oil can be obtained by a method such as centrifugation or natural immersion using a specific gravity difference between an oil and a substance having a different polarity, and has the advantage of eliminating the use of an organic solvent that may be harmful to human body. . Solvent extraction is one of the most generalized extraction methods despite the disadvantages of process complexity such as recovery process and waste water purification process using organic solvent and risk of residual solvent. Supercritical extraction is one of the extraction methods that can solve the problems caused by the use of the organic solvent mentioned above even in the case of solvent extraction. In May 2004, the Korea Food and Drug Administration revised notice No. 2004-41 approved the use of supercritical extraction methods for extracting edible oils and fats to provide safe food to the public and contribute to the improvement of food industry by introducing new technologies. . Supercritical fluids can be set to any condition from high density to low density by manipulating pressure and temperature, resulting in high purity products with excellent selectivity for fractionation and separation, and almost completely recovering the extraction solvent without loss. It can be, and there is an advantage to obtain a purified product with no residual solvent. Supercritical carbon dioxide is used as a nonpolar solvent in various extraction of low polar substances such as fats and oils. In addition, since some polar substances such as alcohol can be added, the solubility of the supercritical fluid can be easily induced, thereby significantly changing the dissolving power. It can also be used to extract components other than triglycerides. However, the extraction of microalgae produced through fermentation has a disadvantage that the supercritical extraction efficiency of the microalgae with high moisture content is significantly lower than that of the dry supernatant. . This may act as a factor that cannot take advantage of supercritical extraction, which can overcome the shortcomings of high initial facility investment.

The mechanical method refers to a method of extracting a cell of a microalgae by rupturing or pulverizing to obtain an oil present in the cell. Representative methods are the use of milling devices such as colloid mills and bead mills. In the case of colloid mill, it is a dry and wet ultra-micron grinder that can be used to grind fine algae precisely by using the high-speed rotational power of the grinder. In the case of the bead mill, the microalgae is dispersed and broken by using the kinetic energy of the beads generated by the energy of the motor.

Currently, a method of obtaining crude oils containing unsaturated fatty acids, in particular, omega-3 based or omega-6 based fluorinated fatty acids from microalgae is used to extract the microalgae after drying. In addition to this process, problems such as a large amount of time and economic loss to obtain unsaturated fatty acids occur.

Therefore, there is a need for a novel method for extracting crude oil from microalgae that can solve the problems occurring in the crude oil extraction process step.

Numerous papers and patent documents are referenced and cited throughout this specification. The disclosures of cited papers and patent documents are incorporated herein by reference in their entirety, and the level of the technical field to which the present invention belongs and the contents of the present invention are more clearly explained.

The present inventors endeavored to develop a method which can dramatically improve the productivity of crude oil containing unsaturated fatty acids by significantly increasing the yield of crude oil from microalgae. As a result, the present invention has been completed by elucidating that crude oil can be obtained from the microalgae more quickly and simply by physically crushing the microalgae in a wet state without the process of drying.

It is therefore an object of the present invention to provide a method for extracting crude oil from microalgae.

Other objects and advantages of the present invention will become more apparent from the following detailed description of the invention, claims and drawings.

According to one aspect of the invention, the present invention comprises the steps of (a) physically crushing the microalgae in the wet state; And (b) extracting crude oil from the microalgae crushed by the step (a) using an extracting solvent, wherein the crude oil is extracted from the microalgae. .

The present inventors endeavored to develop a method which can dramatically improve the productivity of crude oil containing unsaturated fatty acids by significantly increasing the yield of crude oil from microalgae. As a result, it was found that crude oil can be obtained more quickly and simply from the microalgae by physically crushing it without physically crushing the microalgae containing moisture and then adding an extraction solvent.

As used herein, the expression “wet microalgae” means microalgae containing water as it is in a natural or cultured state.

The expression “crude oil” in the context of the present invention means all kinds of oils contained in microalgae, for example, polyunsaturated fatty acids (eg, omega-3 unsaturated fatty acids and omega-6 unsaturated fatty acids), lau Saturated fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid and arachidic acid, phospholipids and steroids Steroid) family of compounds.

The present invention relates to a method for extracting crude oil from microalgae containing a large amount of polyunsaturated fatty acids present in nature.

Preferably, the polyunsaturated fatty acid in the present invention means an omega-3 unsaturated fatty acid, more preferably docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), arachidone Esters such as acids (Arachidonic acid (ARA), docosapentaenoic acid (DPA), and α-linolenic acid) and ester combinations thereof, and more preferably DHA or EPA, most preferably Is DHA.

According to a preferred embodiment, the microalgae of the present invention progenitor kit Solarium (Schizochytrium), A teurawooseu talkie yttrium (Thraustochytrium), A-party phono kit Solarium (Japonochytrium) in wool Kenny O (UIkenia), A creep Te Cody nium (Crypthecodinium) in or Harley neoplasm? Ross (Haliphthoros) is spp, more preferably eponymous kit Leeum (Schizochytrium) in or teurawooseu Torquay yttrium (Thraustochytrium) and in strains, most preferably eponymous kit Leeum (Schizochytrium) in which Strain.

Step (a) in the present invention is carried out by wet crushing the microalgae containing the moisture as it is, not the dried microalgae.

The expression "physical crushing" used while performing the step (a) in the present invention refers to a process of crushing the microalgae using equipment (that is, a crusher) capable of breaking the cell wall of the microalgae.

The present invention is characterized in that in the method of extracting crude oil from the microalgae, the crude algae are extracted by using an extraction solvent after physically crushing the microalgae containing water without the process of drying the microalgae.

According to a preferred embodiment of the present invention, the step of physically crushing the microalgae in the step (a) of the present invention is a bead mill, french pressure, homogenizer or homogenizer. A microfluidizer is used, more preferably a bead mill or homogenizer, and most preferably a bead mill.

The step (a) in the present invention preferably further comprises the step of adding an organic solvent in order to maximize the efficiency of the microalgae crushing process.

According to a preferred embodiment of the present invention, the organic solvent used in step (a) in the present invention is methanol, ethanol, butanol, isopropyl alcohol, pentane, hexane, heptane, cyclohexane, toluene, acetone, methyl acetate, methylene At least one organic solvent selected from the group consisting of chloride, chloroform, ether, petroleum ether, benzene, ethylene glycol, propylene glycol and butylene glycol, more preferably methanol, ethanol, butanol, isopropyl alcohol, pentane and hexane At least one organic solvent selected from the group consisting of, even more preferably methanol or ethanol, most preferably ethanol.

In the present invention, the amount of the organic solvent in the step (a) is not limited, and can be adjusted according to the situation.

According to a preferred embodiment of the present invention, the amount of the organic solvent in the step (a) in the present invention is 1: 0.5-1: 3% by weight based on the weight of the microalgae, more preferably 1: 0.8-1: 1.5 weight %, Most preferably 1: 1 weight.

In the present invention, the step of physically crushing in step (a) can be carried out without any special time constraint.

According to a preferred embodiment of the invention, step (a) in the present invention is carried out for 5-300 minutes, more preferably 10-200 minutes, even more preferably 15-150 minutes, most preferably 20- For 120 minutes.

The extraction solvent used in step (b) in the present invention is a conventional extraction solvent known in the art, (a) water, (b) anhydrous or hydrous lower alcohol having 1 to 4 carbon atoms (e.g. methanol, ethanol, propanol, Butanol, normal-propanol, iso-propanol and normal-butanol, etc.), (c) a mixed solvent of the lower alcohol with water, (d) acetone, (e) ethyl acetate, (f) chloroform, (g) 1, 3-butylene glycol, (h) hexane, (i) diethyl ether, or (j) butyl acetate are used, more preferably lower alcohol or hexane, most preferably hexane.

The present invention may include a conventional purification process. That is, by performing a desoldering process according to a known method (US Pat. No. 6,812,009), it is possible to perform a process for removing saturated fatty acids, and also degumming, deoxidizing, desoldering, according to a known method (US Pat. No. 6,750,048). It is possible to remove phospholipids, free fatty acids, pigments, residual saponified substances, low-molecular volatile substances causing odors by performing fat or oil manufacturing processes such as decolorization and deodorization.

The features and advantages of the present invention are summarized as follows:

(Iii) The present invention provides a method for extracting crude oil from wet microalgae.

(Ii) The present invention is obtained by physically crushing a microalgae in a wet state obtained through fermentation (particularly, by crushing by bead mill) to obtain crude oil containing a functional substance (eg, omega-3 unsaturated fatty acid). There is an advantage in the process that can be obtained faster and more economically than the conventional dry extraction method.

(Iii) The present invention has the advantage of preventing the degeneration of the functional material contained in the microalgae, as compared with the method of extracting by adding chemicals such as heat treatment, acid base and chelate compounds.

(Iii) It also provides basic data in the food or pharmaceutical industry using functional materials extracted from the microalgae of the present invention.

1 is a crude oil extracted from the microalgae crushed using a bead mill after adding or not adding ethanol to the wet microalgae ( Schizochytrium sp. CC44; KCTC 11566BP) in the present invention It is the result of comparing the yields of.
2 is 20, 40, 60, 80 and 120 hours in the step of crushing the microalgae using a bead mill after adding ethanol to the wet microalgae ( Schizochytrium sp. CC44; KCTC 11566BP) in the present invention It is the result which showed the yield of crude oil measured every time.
Figure 3a-3b is an optical microscope image of the microalgae (schizochytrium sp. CC44; KCTC 11566BP) before and after crushing bead mill in the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention in more detail, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples in accordance with the gist of the present invention. .

Example

Throughout this specification, "%" used to denote the concentration of a particular substance is intended to include solids / solids (wt / wt), solid / liquid (wt / The liquid / liquid is (vol / vol)%.

Example 1 Crude Oil Yield by Using Organic Solvents in Microalgae Crushing Process

In the crude oil yield according to the bead mill crushing conditions of wet microalgae ( Schizochytrium sp. CC44; KCTC 11566BP), the difference in the yield with or without the addition of the organic solvent during the crushing process was examined.

The organic solvent was 99% ethanol (Duksan Chemical Co., Ltd., purity 99.9%) and ethanol of 1: 1, 1: 2 and 1: 3 to the weight of the microalgae was added, respectively. The crude oil yields of ethanol use were examined by comparing and analyzing the microalgae which had been subjected to bead mill crushing without addition.

The analytical method consists of crushed microalgae without ethanol and ethanol in 1: 1, 1: 2 and 1: 3% by weight ratio compared to crude oil (100%) contained in the microalgae without crushing. The microalgae crushed by addition to the crude oil was extracted using hexane and then compared with the relative amount of crude oil obtained by concentration. The amount of crude oil of uncrushed microalgae, which is the standard, was tested according to Food Code Article 10. General Test Method 1.Food Ingredient Test Method 1.1.5.1 Crude Fat Test Method and the results were obtained. The crude oil of the crushed microalgae was extracted using hexane. The bead mill uses DYNO-MILL from WAB, Switzerland. The glass beads used were 70-73% silicon oxide, 1.5% aluminum oxide, 10-15% sodium oxide, 1.0-4.5% magnesium oxide and 7-13% calcium oxide. A 0.8 mm diameter spherical bead having a content was used. The temperature in the reactor was maintained at 30 ℃ and the reaction time was fixed to 1 hour was applied equally to each experimental group with different amounts of ethanol (Fig. 1).

As a result, the yield of crude oil was about 2.3 times different depending on the presence or absence of ethanol.

Example 2 Evaluation of the Effect of Bead Mill Fracture Time on Crude Oil Yield

The difference in crude oil yield according to the amount of ethanol added to the organic solvent was confirmed. Then, the yield of crude oil according to the bead mill crushing time was analyzed with only the crushing time under the same conditions as in Example 1 with the addition amount of ethanol to the weight of the microalgae in the wet state in a 1: 1 weight ratio.

The analytical method was determined as the ratio of the oil obtained after distillation under reduced pressure by distilling the crude oil with hexane for each sample having a different crushing time compared to the crude oil included in the wet microalgae (Fig. 2).

As a result, crude oil yield was 86.34%, 40 minutes 88.30%, 60 minutes 89.19%, 80 minutes 92.44%, 100 minutes 95.21% and 120 minutes 95.15%, respectively. The above results do not show a big difference when compared with the generally known yield of 95% when dry crushing, and shows a high yield of 90% compared to the 2 hour crushing rate even in a relatively short time of 20 minutes. As a result of analysis of samples taken every 20 minutes, the highest yield was 95.24% for 100 minutes of crushing reaction. The subsequent crushing reaction showed that there was no further effect on breaking the cell wall of microalgae. It was confirmed through.

Claims (7)

(a) physically crushing the microalgae in the wet state; And (b) extracting crude oil from the microalgae crushed by the step (a) using an extraction solvent.
The method of claim 1, wherein the microalgae is progenitor kit Leeum (Schizochytrium), A teurawooseu Torquay Yttrium (Thraustochytrium), A party phono kit Leeum (Japonochytrium) in wool Kenny O (UIkenia) in, creep te coordination nium (Crypthecodinium) characterized in that the speed or Harley neoplasm? LOS (Haliphthoros) sp.
The method of claim 1, wherein step (a) comprises physically crushing the microalgae using a bead mill, French presser, homogenizer or homogenizer.
The method of claim 1, wherein step (a) further comprises the step of adding an organic solvent.
The method of claim 4, wherein the organic solvent is methanol, ethanol, butanol, isopropyl alcohol, pentane, hexane, heptane, cyclohexane, toluene, acetone, methyl acetate, methylene chloride, chloroform, ether, petroleum ether, benzene, ethylene glycol At least one organic solvent selected from the group consisting of propylene glycol and butylene glycol.
The method of claim 1 wherein step (a) is performed for 5-300 minutes.
The method of claim 1, wherein step (b) comprises the step of adding 1: 0.5-1: 3% by weight of the extraction solvent relative to the weight of the microalgae.

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