KR20170037046A

KR20170037046A - Method for disruption of biomass

Info

Publication number: KR20170037046A
Application number: KR1020150136103A
Authority: KR
Inventors: 오인선; 김종필
Original assignee: 롯데케미칼 주식회사
Priority date: 2015-09-25
Filing date: 2015-09-25
Publication date: 2017-04-04

Abstract

The present invention relates to a method for finely pulverizing biomass, comprising the following processes: mixing a pulverization agent with a microalgae culture solution; and pulverizing the microalgae culture solution using a milling device. According to the present invention, by increasing pulverization efficiency for microalgae culture solution as well as extraction yields for crude oil, acquisition of microalgae crude oil is possible in a cost-effective way.

Description

[0001] METHOD FOR DISRUPTION OF BIOMASS [0002]

The present invention relates to a method for the micronization of biomass to obtain crude oil from a microalgae culture.

Microalgae are an excellent resource for the production of polyunsaturated fatty acids, which are well tolerated in environments where light is blocked and organic in abundance, and by converting carbohydrates into useful oils, the omega- . However, omega-3 fatty acids derived from microalgae have been attracting attention due to the replacement of fish-derived omega-3 fats, which are likely to be exposed to heavy metals and other problems. The factors that underpin this tendency include the high price of polyunsaturated fatty acids, the availability of high-density unsaturated fatty acids, the superiority of oxidative stability to fish oil, the sustainability of production, the new production of biochemical metabolic pathways and genetic knowledge System and product development means.

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

DHA (docosahexaenoic acid) is a highly unsaturated fatty acid in the omega-3 (ω-3) series, which is mainly composed of 22 carbon atoms and 6 double bonds. DHA is a type of polyunsaturated fatty acid, which is known to be biosynthesized mainly in natural freshwater, seawater and phytoplankton living in seawater. Fish, crustaceans, and shellfish that can not make DHA themselves can accumulate DHA in the form of triglycerides in the body by ingesting plants containing DHA by the food chain. People also have to rely on the intake of DHA containing foods that are needed because the enzymes needed to biosynthesize DHA are not present in the body.

With respect to the production of omega-3 highly unsaturated fatty acids, especially those using docosahexaenoic acid (DHA) in a large amount, microorganisms belonging to the genus Thraustochytrium, a kind of marine microalgae, The preparation of omega-3 unsaturated fatty acids by microorganisms in Schizochytrium has been described by Ellenbogen et al. (Ellenbogen B. B et al., Comparative Biochemistry and Physiology, 29: 805-811 (1969)).

DSM, which produces micro-algae oil industrially, is a microorganism belonging to the genus Shizokitriium sp. A method for preparing omega-3 unsaturated fatty acids using ATCC 20888 (Schizochytrium sp. ATCC 20888) has been disclosed (U.S. Patent No. 5,130,242).

The main process for producing oil from microalgae differs depending on the field of use, but largely consists of the steps of cultivation, extraction and purification of microalgae. The production of polyunsaturated fatty acids, which are used as food products, consists of cultivation, recovery, drying, extraction and purification processes. After the drying process, the intracellular crude oil extraction process using a nonpolar solvent such as hexane, . The extraction method of oil containing microalgae is largely classified into chemical and physical methods according to microalgae pretreatment method. In detail, it can be divided into solventless extraction and solvent extraction depending on whether or not solvent is used during extraction.

In the case of solventless extraction, methods such as enzymatic decomposition reaction, heat treatment, etc. are a method of solventless extraction in which an organic solvent such as hexane is not used or minimized to obtain an oil. In the case of solventless extraction, an oil can be obtained by a method such as centrifugation or natural dipping using the difference in specific gravity between oil and other polar substances, and it is advantageous to exclude the use of an organic solvent which may be harmful to human body .

The oil extraction method commonly used in the prior art is a solvent extraction method using a nonpolar organic solvent such as hexane. In the case of solvent extraction, it is applied to many domestic and foreign companies because it is a process that can realize economies of mass production despite cost increase in process operation and risk of residual solvent due to use of organic solvent.

In the case of solvent extraction, it is applied in connection with the physical method of the pretreatment concept in which the cells of microalgae are ruptured or disrupted in order to obtain the oil present in the cells. As a typical method, a milling apparatus such as a colloid mill and a bead mill is used. In the case of a colloid mill, a super-atomized crusher capable of dry and wet operation is a principle in which particles of a mixture are dispersed or disrupted because a rotor rotates at a high speed and a high shear energy is generated between a very small gap between a rotor and a stator . In the case of the bead mill, the kinetic energy of beads generated by the energy of the motor can be used to disperse and crush the microalgae.

When the useful substance is a nonpolar oil, it can be classified into a solvent extraction method using a nonpolar solvent such as hexane and a solventless extraction method using no solvent.

As a method to maximize extraction efficiency, biomass pretreatment can be usually performed, which can be divided into chemical, physical, and enzymatic methods. In the case of enzymatic disruption, applicable enzymes may be limited when the useful substance is a food material. In order to increase the hydrolysis efficiency, difficulties in process operation, which requires precise control to maintain the enzymatic activity, and relatively expensive enzymes It can be a disadvantage in terms of economy.

In addition, it is necessary to prove the harmlessness of the final products and the fact that only the limited substances which are notified by the Food and Drug Administration can be used when applying food materials.

In the case of a physical milling method such as a ball mill, there is a disadvantage in that the crushing efficiency is relatively inferior to the energy applied, and when the biomass including the culturing process is applied, it is not economical in terms of processing a maximum of tens of tons of culture liquid .

In the case of a colloid mill which can be applied as an alternative, it may be a method of effectively crushing powder using a friction force between a rotor and a stator. However, in the case of a biomass having a particle size distribution of several microns, The milling process can be repeated several times depending on the degree of crushing. Repetition of the milling process can accelerate rancidity of the crude oil due to the generation of frictional heat, and it is a problem to be overcome in terms of economics by evaporating the mixed solvent.

At present, a general method for commercially producing a crude oil containing polyunsaturated fatty acids, especially omega-3 or omega-6 unsaturated fatty acids, from microalgae is a method of drying microalgae and subjecting them to physical disruption. However, in the above method, there is a problem that economical efficiency due to rancidity of the crude oil due to frictional heat during the crushing process and deterioration of the extraction yield is low. Therefore, it is necessary to develop a crushing process capable of effectively obtaining a microalgae crude oil having a high economic efficiency with an increased extraction yield.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the prior art, and it is an object of the present invention to provide a biomass pulverization method for efficiently pulverizing a microalgae culture broth to obtain crude oil.

In order to achieve the above object,

The present invention relates to (A) mixing and drying a crushing agent in a microorganism culture fluid containing an oil;

(B) adding an organic solvent to the dried crushed mixture culture medium (A) and crushing the mixture using a milling apparatus;

(C) adding an extraction solvent to the pulverized culture liquid (B), stirring the mixture to extract oil, and precipitating to phase-separate the solvent layer;

(D) filtering the separated solvent layer (C) using a filter.

In the microfibrillation method of the biomass of the present invention, the microorganism containing the oil may be at least one selected from the group consisting of microalgae, bacteria, yeast and fungi.

The microalgae are selected from the group consisting of Schizochytrium sp., Thraustochytrium sp., Japonochytrium sp., Ulkenia sp., And Creepecodinium sp. (Crypthecodinium sp.).

The crusher may be silica, and the silica may be at least one selected from the group consisting of precipitated silica, fumed silica, amorphous silica, diatomaceous silica, and silane treated forms of the silica.

The crusher may be selected from the group consisting of aluminum oxide (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), calcium oxide (CaO), magnesium oxide (MgO), titanium dioxide (TiO ₂ ), sodium oxide (Na ₂ O) (P ₂ O ₅ ), potassium oxide (K ₂ O), manganese oxide (MnO), and chromium oxide (Cr ₂ O ₃ ).

The extraction solvent is selected from the group consisting of water, methanol, ethanol, propanol, butanol, iso-propanol, n-butanol, acetone, ethyl acetate, chloroform, 1,3-butylene glycol, hexane, diethyl ether and butyl acetate Or one or more selected from the group consisting of

The milling apparatus may be at least one selected from a colloid mill, a bead mill, a ball mill, and a combination thereof.

The oil may be at least one selected from saturated fatty acids, phospholipids, steroids, free fatty acids and esters and derivatives thereof.

The oil may be at least one selected from n-3 fatty acids and n-6 fatty acids.

The present invention also provides a microbial oil by the above method.

The microbial oil may be a highly unsaturated fatty acid, and may be at least one selected from n-3 fatty acids and n-6 fatty acids.

According to the present invention, a crude oil is obtained from a microalgae culture medium by a biomass pulverization method including a biomass crushing process using a milling apparatus in which a crushing agent is mixed with a crusher of a certain size, , The extraction yield of the crude oil is increased and the process is highly economical. Therefore, the crude oil obtained from the microalgae by the above method can be widely used in the food industry, the cosmetics industry, and the like.

1 is a graph showing the crude oil extraction yield according to the number of milling cycles and the presence or absence of crushing agent.
2 is a graph showing the crude oil extraction yield according to the average particle diameter of the crushing agent.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, "crude oil" means all kinds of oils contained in microalgae, and examples thereof include highly unsaturated fatty acids (omega-3, omega-6, omega-9 unsaturated fatty acids) Saturated fatty acids such as Lauric acid, Myristic acid, Palmitic acid and Stearic acid, Phospholipid and Steroid series compounds. It may also exist as free fatty acids as well as esters and other derivatives.

In the present invention, 'drying' refers to a method of removing water, and includes, for example, membrane filter press drying, spray drying, fluidized bed drying, lyophilization Freeze drying, tray drying, vacuum tray drying, drum drying, vacuum mixer / reactor drying, excipient drying, Solvent drying, fluidized spray drying, conveyer drying, ultrafiltration, evaporation, osmotic dehydration, freezing, air drying, and the like. air drying, tunnel drying, or a combination thereof.

In the present invention, the polyunsaturated fatty acid is a polyunsaturated long chain fatty acid having a chain length of more than _C12 containing two or more double bonds. Preferably n-3 fatty acids and n-6 fatty acids, more preferably n-3 fatty acids.

In the present invention, the 'n-type fatty acid' is classified according to the position of the first double bond from the methyl (CH ₃ ) group of the unsaturated fatty acid structure and the 'n-3 fatty acid' Linolenic acid (18: 3), Eicosa pentanoic acid (EPA, 20: 5) and docosahexaenoic acid (EPA), which are abundantly contained in perilla oil and freshwater fish. DHA, 22: 6), and the n-6 fatty acid is also called omega-6 (omega-6) and contains linoleic acid (18: 2) and arachidonic acid (20: it means.

Hereinafter, the present invention will be described in detail.

The method for micronization of a biomass of the present invention comprises the steps of (A) mixing and drying a crushing agent in a microorganism culture fluid containing oil; (B) adding an extraction solvent to the dried crushed mixture (A) and crushing the mixture using a milling machine; (C) adding an organic solvent to the pulverized culture liquid (B) and stirring to extract oil and precipitate to phase-separate the solvent layer; (D) filtering the separated solvent layer (C) using a filter.

The microorganism containing the oil is preferably at least one selected from the group consisting of microalgae, bacteria, yeast and fungi, more preferably microalgae.

The microalgae may be selected from the group consisting of Schizochytrium sp . ), The genus Thraustochytrium sp . ), The genus Japonochytrium sp . ), The genus Ulkenia ( Ulkenia sp . ) And the genus Crypthecodinium sp . ), More preferably at least one selected from the group consisting of Schizochytrium sp . ), Still more preferably Schizochytrium < RTI ID = 0.0 > limacinum SR21 . )to be.

The crushing agent is preferably silica.

The silica is preferably selected from the group consisting of precipitated silicas, fumed silicas, amorphous silicas, diatomaceous silicas and silane treated forms of the silicas.

According to a preferred embodiment of the present invention, the crushing agent may be mixed in a proportion of 1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the total solid content in the culture liquid.

The crusher may be selected from the group consisting of aluminum oxide (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), calcium oxide (CaO), magnesium oxide (MgO), titanium dioxide (TiO ₂ ), sodium oxide (Na ₂ O) (P ₂ O ₅ ), potassium oxide (K ₂ O), manganese oxide (MnO) and chromium oxide (Cr ₂ O ₃ ).

According to a preferred embodiment of the present invention, the mixture may be mixed at a ratio of at least 80 parts by weight of silicon dioxide, more preferably at least 85 parts by weight of silicon dioxide, based on 100 parts by weight of the mixture.

The extraction solvent is selected from the group consisting of water, methanol, ethanol, propanol, butanol, iso-propanol, n-butanol, acetone, ethyl acetate, chloroform, 1,3-butylene glycol, hexane, diethyl ether and butyl acetate , And more preferably at least one selected from the group consisting of hexane.

The milling apparatus is preferably at least one selected from a colloid mill, a bead mill, a ball mill and a combination thereof, and more preferably a colloid mill.

The oil is preferably at least one selected from saturated fatty acids, phospholipids, steroids, free fatty acids and esters and derivatives thereof.

In the present invention, the oil is a polyunsaturated fatty acid, and the unsaturated fatty acid is a polyunsaturated long chain fatty acid having a chain length of C ₁₂ or more containing two or more double bonds, preferably the oil is n-3 fatty acid and n-6 fatty acid , More preferably n-3 fatty acid.

In a preferred embodiment of the present invention, the polyunsaturated fatty acid contains omega-3-docosahexaenoic acid (DHA) and / or omega-3-docosapentaenoic acid (DPA).

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to be illustrative of the present invention and the scope of the invention as defined by the appended claims. And it is clear that such modifications and variations are included in the scope of the appended claims.

< Preparation Example 1> Culture of microalgae

A microscopic algae, Scnizochytrium limacium SR21, microorganism international accession number ATCC ^? MYA-1381TM, which produces crude oil, was cultured to obtain a biomass in a wet state, that is, a culture liquid.

250 ml of a medium (glucose 10 g / l, peptone 1 g / l, yeast extract 5 g / l and seawater salt 18 g / l), Scnizochytrium limacium SR21 microorganism international accession number ATCC ^? MYA-1381 TM) L, 0.2 g / l of calcium chloride, 0.3 g / l of calcium chloride, 0.3 g / l of calcium chloride and 1.0 g / l of sodium nitrate were added to the culture medium. 2 l of the microparticle component II (5 ml / l), 0.05 g / l of potassium dihydrogenphosphate, 1.0 g / l of the trace component I, 5 ml / And inoculated and cultured at 28 DEG C with shaking at 200 rpm for 72 hours.

The culture medium as described above was washed three times to completely remove the medium components, dried at 105 ° C and weighed to determine the amount of biomass, and the amount of the biomass was measured according to Article 10. General Testing Methods 1. Food Test Method 1.1.5.1 The amount of crude oil contained in the culture solution was measured according to the crude fat test method. As a result, the amount of biomass was 62.5 g / L and the content of crude oil was 61.7%.

< Example 1 to 2> Biomass By the finely pulverizing method Joe Oils extraction

In the method of extracting crude oil from the microalgae culture prepared in Preparation Example 1, the extraction yield according to the presence or absence of the crushing agent and the number of milling, the extraction yield according to the size of the crusher, Were examined in the following manner.

The average particle diameter of the crushing agent (product name) Example 1 10 mu m (YH-500) Example 2 27 탆 (YH-250) Comparative Example 1 -

One. Crusher Drying of the mixed culture

Diatomaceous earth having an average particle diameter of 10 mu m and diatomaceous earth having an average particle diameter of 27 mu m (YH-500 (average particle diameter 10 mu m), YH-250 (average particle diameter Mu] m) was added and homogenized using a stirrer. The diatomaceous earth was added in an amount of 10 parts by weight based on 100 parts by weight of the total solid content in the microalgae culture broth. The culture liquid containing the diatomite was dried at a blowing temperature of 100 ° C and an air temperature of 170 ° C using a spray drier (Sogang Engineering Co., Ltd., Model KL-8) to adjust the amount of liquid to be fed and to have a final moisture content of 5% or less.

2. Colloid mill Shredding

After 200 parts by weight of hexane was added to 100 parts by weight of the dried crushed mixture culture solution, stirring was continued until the colloid mill was fed in order to prevent phase separation, and the mixture was added to a colloid mill (μ-TRON LAB / P) And milled at a number of milling revolutions of 8,000 rpm to be crushed. The crushed culture broth was recovered in its entire volume without lysing to confirm the extraction yield.

3. Extraction yield Analysis and evaluation of shredding efficiency

Hexane was added to the culture solution recovered through the milling process so as to be 200 parts by weight based on 100 parts by weight of the culture solution, and the crude oil was extracted by stirring at 300 rpm for 30 minutes. Thereafter, to obtain a solvent layer, the solution was subjected to a precipitation process for about 30 minutes, followed by filtration under reduced pressure using a GF-B filter having a pore size of 1 μm to prevent a small amount of impurities from being mixed. The above procedure was repeated five times in total until the solute was no longer dissolved in the solvent.

The results of the experiment are shown in FIG. 1 and FIG.

As shown in Fig. 1, it was confirmed that the extraction yield of the crude oil was improved by about 50% as compared with no addition at 10% of the crushed powder having an average particle diameter of 10 mu m.

2, the extraction yield of the crude oil according to the size of the crusher was evaluated by adding a crushing agent having an average particle diameter of 10 mu m, It was confirmed that the extraction yield of about 6% was improved.

From the above results, it was confirmed that the extraction yield of the crude oil increased when the crushing agent was added to the micro-pulverization of the biomass containing the crushing agent according to the present invention.

Claims

(A) mixing and drying a crushing agent in a microorganism culture solution containing oil;
(B) adding an organic solvent to the dried crushed mixture culture medium (A) and crushing the mixture using a milling apparatus;
(C) adding an extraction solvent to the pulverized culture liquid (B), stirring the mixture to extract oil, and precipitating to phase-separate the solvent layer;
(D) filtering the separated solvent layer (C) using a filter.

The method according to claim 1,
Wherein the microorganism containing the oil is at least one selected from the group consisting of microalgae, bacteria, yeast, and fungi.

3. The method of claim 2,
The microalgae are selected from the group consisting of Schizochytrium sp., Thraustochytrium sp., Japonochytrium sp., Ulkenia sp., And Creepecodinium sp. (Crypthecodinium sp.). &Lt; RTI ID = 0.0 > 21. < / RTI >

The method according to claim 1,
Wherein the crushing agent is silica.

5. The method of claim 4,
Wherein the silica is at least one selected from the group consisting of precipitated silica, fumed silica, amorphous silica, diatomaceous silica and silane treated forms of the silica.

The method according to claim 1,
The crusher may be selected from the group consisting of aluminum oxide (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), calcium oxide (CaO), magnesium oxide (MgO), titanium dioxide (TiO ₂ ), sodium oxide (Na ₂ O) Characterized in that it further comprises at least one selected from the group consisting of P ₂ O ₅ , potassium oxide (K ₂ O), manganese oxide (MnO) and chromium oxide (Cr ₂ O ₃ ) Way.

The method according to claim 1,
The extraction solvent is selected from the group consisting of water, methanol, ethanol, propanol, butanol, iso-propanol, n-butanol, acetone, ethyl acetate, chloroform, 1,3-butylene glycol, hexane, diethyl ether and butyl acetate Wherein the biomass is one or more selected from the group consisting of:

The method according to claim 1,
Wherein the milling apparatus is at least one selected from a colloid mill, a bead mill, a ball mill, and a combination thereof.

The method according to claim 1,
Wherein the oil is at least one selected from saturated fatty acids, phospholipids, steroids, free fatty acids and esters and derivatives thereof.

The method according to claim 1,
Wherein the oil is a polyunsaturated long chain fatty acid having a chain length of C ₁₂ or more.

The method according to claim 1,
Wherein the oil is at least one selected from n-3 fatty acids and n-6 fatty acids.

12. A microbial oil according to any one of claims 1 to 11.