Method for obtaining target compounds from fermentation broth

Abstract

To provide a method for obtaining a target compound from a fermentation broth. The present invention relates to a method for obtaining a compound of interest by removing at least a portion of insoluble substances or macromolecules from a fermentation broth and then recovering the compound of interest by carrying out one or more of the following steps (a) to (c): (a) increasing the concentration of a compound of interest in a fermentation broth; (b) reducing the concentration of residual carbon sources or alcohol in the fermentation broth; (c) A step of reducing the concentration of ionic components in the fermentation liquid.

Description

[Technical Field]

[0001] The present invention relates to a method for obtaining a compound of interest from a fermentation broth. [Background technology]

[0002] 3-Hydroxypropionic acid (3-HP) can be produced by chemical synthesis or microbial fermentation, and in recent years, methods for producing 3-HP using bacteria such as Escherichia coli and Klebsiella have been studied. For example, Korean Patent Publication No. 10-2020-0051375 discloses a technology for producing 3-HP using microorganisms transformed with specific genes.

[0003] The present invention relates to a method for obtaining and separating 3-HP from a fermentation broth containing 3-HP produced by culturing a microorganism. Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a method for obtaining a compound of interest from a fermentation broth. [Means for solving the problem]

[0005] In order to achieve the above object, the present invention provides: The present invention provides a method for recovering a compound of interest by removing at least a portion of insoluble substances or macromolecules from a fermentation broth and then carrying out one or more of the following steps (a) to (c): (a) increasing the concentration of the compound of interest in the fermentation broth; (b) reducing the concentration of residual carbon sources or alcohols in the fermentation broth; (c) A step of reducing the concentration of ionic components in the fermentation broth. [Effects of the Invention]

[0006] The method of the present invention allows the isolation of the target compound from the fermentation broth in high yield. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram showing a method for obtaining the compound of the present invention. [Figure 2] These are the results of a test in which insoluble matter was separated from the fermentation liquid using a microfilter. [Figure 3] This is the result of confirming the peaks of 3-HP, 1,3-propanediol, and glycerol in the fermentation broth by single column chromatography. [Figure 4] FIG. 1 is a diagram showing a process of precipitating and removing calcium ions in a fermentation broth. [Figure 5] FIG. 10 is a graph showing changes in ion concentration in a fermentation broth due to ion exchange. [Figure 6] FIG. 1 is a diagram showing a process of removing ions from a fermentation broth by ion exchange. [Figure 7] FIG. 1 is a diagram showing a process of removing ions from a fermentation broth by electrodialysis. DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention provides A method for obtaining a compound by removing at least a portion of insoluble substances or macromolecules from a fermentation broth and then recovering the compound of interest by carrying out one or more of the following steps (a) to (c): (a) increasing the concentration of the compound of interest in the fermentation broth; (b) reducing the concentration of residual carbon sources or alcohols in the fermentation broth; (c) A step of reducing the concentration of ionic components in the fermentation liquid.

[0009] In this case, when one or more of the above steps (a) to (c) are carried out, any step can be repeated two or more times.

[0010] The above step (a) can be carried out by one or more methods selected from the group consisting of evaporation, concentration and distillation.

[0011] The above step (c) can be carried out by the following (c)' or (c)'': (c)': A process of treating the fermentation liquid with acid to precipitate ionic components and then removing them. (c) : A step of treating the fermentation liquid with one or more methods selected from the group consisting of electrodialysis, ion exchange, and chromatography.

[0012] The insoluble matter may include cells, and the macromolecules may be proteins, polysaccharides, or lipids. In this case, at least a portion of the insoluble matter may be removed from the fermentation broth, or at least a portion of the macromolecules may be removed, or at least a portion of the insoluble matter and at least a portion of the macromolecules may be removed. In this case, at least a portion of the insoluble matter may be removed from the fermentation broth, and then at least a portion of the macromolecules may be removed. Alternatively, at least a portion of the macromolecules may be removed from the fermentation broth, and then at least a portion of the insoluble matter may be removed. The target compound may be an organic acid produced by microbial fermentation, preferably 3-hydroxypropionic acid (3-HP). The carbon source in (b) above may be glycerol or glucose. The alcohol in (b) above may be an alcohol produced by microbial fermentation, such as 1,3-propanediol.

[0013] In a preferred embodiment of the present invention, the method for obtaining the compound of the present invention can be carried out by removing at least a portion of the insoluble materials and at least a portion of the macromolecules from the fermentation broth, first (a) increasing the concentration of the target compound in the fermentation broth, (b) reducing the concentration of residual carbon sources or alcohols in the fermentation broth, (c)': treating the fermentation broth with an acid to precipitate ionic components and then removing them, and then (c)'': treating the fermentation broth with one or more methods selected from the group consisting of electrodialysis, ion exchange, and chromatography, and secondly (a) increasing the concentration of the target compound in the fermentation broth, and then recovering the target compound to obtain the compound.

[0014] The fermentation liquid may be a fermentation liquid prepared by the following step 1: preparing a fermentation liquid.

[0015] The step of removing at least a portion of the insoluble substances or macromolecules from the fermentation broth may be the following step 2: step of separating insoluble substances or the following step 3: step of removing macromolecules and decolorizing.

[0016] The above first (a) step of increasing the concentration of the compound of interest in the fermentation broth may be the following step 4: increasing the concentration of 3-HP in the fermentation broth.

[0017] The above step (b) of reducing the concentration of the residual carbon source or alcohol in the fermentation broth may be the following step 5: reducing the concentration of glycerol or alcohol in the fermentation broth.

[0018] The above (c)': step of treating the fermentation broth with an acid to precipitate and then remove ionic components may be the following step 6: step of reducing ionic components in the fermentation broth (precipitation and filtration).

[0019] The above (c): step of treating the fermentation liquid with one or more selected from the group consisting of electrodialysis, ion exchange, and chromatography may be the following step 7: step of reducing ionic components in the fermentation liquid (electrodialysis and ion exchange).

[0020] The second (a) step of increasing the concentration of the compound of interest in the fermentation broth may be the following step 8: increasing the concentration of 3-HP in the fermentation broth.

[0021] The step of recovering the target compound may be the following step 9: recovery step.

[0022] Step 1: Preparation of fermented liquid The method for obtaining the compound of the present invention may include a step of preparing a fermentation liquid. The fermentation liquid may be a fermentation liquid (fermentation broth) obtained by fermentation using a microorganism, i.e., a culture liquid. The culture liquid may further contain other components in addition to 3-HP and a salt thereof. For example, the culture liquid may contain a calcium salt of 3-HP. The other components may be a carbon source (e.g., glycerol, etc.), an organic acid (e.g., asthenoic acid, etc.), a salt (e.g., sulfate, phosphate, etc.), an alcohol (e.g., diol), a sugar, calcium, etc., used in culturing the microorganism.

[0023] The concentration of 3-HP or a salt thereof in the fermentation broth may be, for example, about 10,000 to 200,000 ppm, for example, about 12,000 to 190,000 ppm, for example, about 15,000 to 180,000 ppm, for example, about 20,000 to 150,000 ppm, for example, about 25,000 to 130,000 ppm, or for example, about 30,000 to 110,000 ppm. According to an embodiment, the concentration of 3-HP or a salt thereof in the fermentation broth may be, for example, about 10,000 ppm or more, for example, about 12,000 ppm or more, for example, about 15,000 ppm or more, for example, about 20,000 ppm or more, for example, about 25,000 ppm or more, or for example, about 30,000 ppm or more. In some embodiments, the concentration of 3-HP or a salt thereof in the fermentation broth may be, for example, 200,000 ppm or less, for example, about 190,000 ppm or less, for example, about 180,000 ppm or less, for example, about 150,000 ppm or less, for example, about 130,000 ppm or less, for example, about 110,000 ppm or less.

[0024] This method may further include a step of adjusting the pH of the fermentation broth. The pH can be adjusted by treating the fermentation broth with an acid or alkali. The type of acid or alkali is not particularly limited, and any acid or alkali commonly used to adjust the pH of a fermentation broth can be used. For example, the desired pH can be adjusted appropriately depending on the type of compound to be separated from 3-HP and the method of the subsequent separation step.

[0025] Step 2: Separation of insoluble matter The method for obtaining the compound of the present invention may include a step of separating at least a portion of the insoluble matter from the fermentation broth. In this case, the fermentation broth may be the fermentation broth prepared in step 1 or the fermentation broth that has been subjected to steps 1 and 3, i.e., a treated broth. The insoluble matter may be microorganisms, i.e., cells, solids, etc.

[0026] The separation of the insoluble material can be carried out using, but is not limited to, a centrifuge, a filtration process, etc., thereby separating the microorganisms, i.e., cells, from the fermentation broth.

[0027] For example, microorganisms and solids in the fermentation broth can be removed by microfiltration. Microfiltration can be performed by passing the fermentation broth through a polymer or ceramic membrane with a pore size of 0.04 to 5 μm. The microfiltration process can consist of two or more steps depending on the tendency for the flux (throughput per unit area and unit time of the membrane) to decrease. In one embodiment, when the flux decreases significantly, additional water can be added to the fermentation broth to increase the recovery rate.

[0028] Step 3: Removal of macromolecules and decolorization The method for obtaining the compound of the present invention may include a step of separating at least a portion of the macromolecules from the fermentation broth. In this case, the step of separating at least a portion of the macromolecules from the fermentation broth may include a step of removing and decolorizing the macromolecules in the fermentation broth. In this case, the fermentation broth may be the fermentation broth prepared in step 1 or the fermentation broth that has undergone steps 1 and 2, i.e., a treated broth. The macromolecules may be proteins, polysaccharides, lipids, etc.

[0029] In one embodiment, the macromolecule removal and decolorization process can be performed by mixing activated carbon and a filter aid with the fermentation liquor and then filtering the mixture. Specifically, in one embodiment, activated carbon and a filter aid (diatomaceous earth, white earth, etc.) are mixed with the fermentation liquor from which the microorganisms have been removed, and the mixture is then filtered (e.g., using a filter press, etc.) to achieve the macromolecule removal and decolorization effects. The filtration can be performed using any commonly used powder particle filtering method (e.g., a filter press, a drum filter, a candle filter, a leaf filter, etc.), and is not particularly limited.

[0030] The addition of activated carbon removes some macromolecules, such as proteins and polysaccharides, thereby suppressing the formation of sticky substances that may occur during the subsequent process of increasing the 3-HP concentration. Activated carbon can be used in both powdered and granular form. For example, adding 0.1–2 wt% of powdered activated carbon to the fermentation broth, stirring at 30–80°C for 1–5 hours, and then filtering the broth, successfully removed its color. When 1.5% of powdered activated carbon was added to the fermentation broth, stirring at 40°C for 1 hour, and filtering, the APHA (American Public Health Association) color value of the fermentation broth was 2.7. Granular activated carbon, when used at a mass fraction of 5–15% of the fermentation broth, can be expected to achieve decolorization performance similar to that of powdered activated carbon. However, in this case, a regeneration system using steam or other methods is required to ensure economic efficiency.

[0031] In yet another embodiment, the macromolecule removal and decolorization process can be performed by membrane separation of the treated solution, which may be ultrafiltration or nanofiltration, and in this case, the macromolecule removal and decolorization effect can be achieved without an additional decolorization process.

[0032] In this case, ultrafiltration is carried out by applying an ultrafiltration membrane with a molecular weight cut-off (MWCO) of 5,000 to 100,000 Da, followed by a nanofiltration membrane with a MWCO of 150 to 300 Da, which minimizes the loss of 3-HP salt while removing only macromolecules such as proteins, polysaccharides, and lipids.

[0033] Step 4: Increasing the concentration of 3-HP in the fermentation liquid The method for obtaining the compound of the present invention may include a step of increasing the concentration of 3-HP in a fermentation broth. In this case, the fermentation broth in step 4 may be a broth treated through steps 2 and / or 3. Alternatively, the fermentation broth in step 4 may be a broth treated through steps 2 and / or 3 followed by one or more of steps 5 to 8. The 3-HP concentration can be increased by evaporating or concentrating at least a portion of the liquid in the fermentation broth. The concentration can be increased by 100 to 500 g of 3-HP equivalent per 1 L of fermentation broth. The increase in concentration may involve adjusting the pressure and can be carried out under an appropriate pressure, for example, at about 20 to 300 mbar, e.g., about 25 to 280 mbar, e.g., about 30 to 250 mbar, e.g., about 50 to 200 mbar, e.g., about 70 to 190 mbar, or e.g., about 80 to 180 mbar, based on absolute pressure. In one embodiment, the increasing step can be performed at, for example, about 20 mbar or less, for example, about 25 mbar or less, for example, about 30 mbar or less, for example, about 50 mbar or less, for example, about 70 mbar or less, for example, about 80 mbar or less, or, for example, about 300 mbar or less, for example, about 280 mbar or less, for example, about 250 mbar or less, for example, about 200 mbar or less, for example, about 190 mbar or less, for example, about 180 mbar or less.

[0034] For example, under conditions of 50 mbar vacuum and maintaining the bath temperature of the rotary evaporator at 50°C, 3-HP could be concentrated to a concentration of 500 g / L or more. At concentrations of 400 g / L or more, it was confirmed that 3-HP calcium salt crystals were formed as the temperature decreased after concentration was completed, and that crystals were also formed during the concentration process as the concentration increased beyond that.

[0035] Step 5: Reducing the concentration of glycerol or alcohol in the fermentation liquid The method for obtaining the compound of the present invention may include a step of reducing the concentration of glycerol or alcohol in the fermentation broth. In this case, the fermentation broth in step 5 may be a treatment broth that has undergone step 2 and / or step 3. Alternatively, the fermentation broth in step 5 may be a treatment broth that has undergone step 2 and / or step 3, followed by step 4 or one or more of steps 6 to 8. The glycerol may be the carbon source used in culturing the microorganism, and the alcohol may be a culture product of the microorganism, such as 1,3-propanediol (1,3-PDO). When glucose is used as a carbon source, the glucose concentration in the fermentation broth may be reduced by step 5. The glycerol or alcohol concentration in the fermentation broth can be reduced by applying chromatography using an ion exchange resin (e.g., simulated moving bed (SMB) chromatography). This is an important factor affecting product quality when polymerizing 3-HP obtained by the method of the present invention. When using HPLC or SMB chromatography, the mobile phase can be injected with the feed to obtain one or more fractions enriched in 3-HP (fraction A) and one or more fractions enriched in other compounds that are not 3-HP (fraction B).

[0036] Step 6: Reducing the ionic components in the fermentation liquid (precipitation and filtration) The method for obtaining the compound of the present invention may include a step of reducing ionic components in the fermentation broth. In this case, the fermentation broth in step 6 may be a treatment broth that has undergone steps 2 and / or 3. Alternatively, the fermentation broth in step 6 may be a treatment broth that has undergone steps 2 and / or 3, followed by one or more of steps 4, 5, 7, and 8. In one embodiment, when step 5 is performed, the largest impurity in the glycerol- and alcohol-reduced fermentation broth is the cation of the pH adjuster added to adjust the pH during the fermentation broth production process. Since different pH adjusters can be used depending on the separation and purification process, the type of cation may vary, typically, but not limited to, calcium, magnesium, etc. These cations exist in the form of various 3-HP salts due to their weak chemical bond with 3-HP, and can be efficiently removed in the form of precipitates by acid treatment. The precipitates can be removed using a filter press, drum filter, etc., but are not limited thereto; any common method for removing precipitates can be used. These acid treatment processes can reduce the pH of the solution to about 1 to 3. For example, the pH can be reduced to about 1.5 to about 2.5, for example, the pH can be reduced to about 1.5 to 2.0.

[0037] Step 7: Reducing the ionic components in the fermentation broth (electrodialysis and ion exchange) The method for obtaining the compound of the present invention may include a step of reducing ionic components in the fermentation broth. In this case, the fermentation broth in step 7 may be a treatment broth that has undergone step 2 and / or step 3. Alternatively, the fermentation broth in step 7 may be a treatment broth that has undergone step 2 and / or step 3, followed by one or more of steps 4 to 6 or 8. In one embodiment, small amounts of ions remaining after removal in step 6 may be further removed in step 7. In step 7, ionic components remaining in the fermentation broth may be separated and reduced by applying a process such as electrodialysis, ion exchange, or SMB chromatography. The ions may be sulfate ions, phosphate ions, sodium ions, ammonium ions, calcium ions, potassium ions, magnesium ions, etc. In this case, the ionic component can be reduced to, for example, about 20,000 ppm or less, for example, about 19,000 ppm or less, for example, about 18,500 ppm or less, for example, about 18,000 ppm or less, for example, about 17,500 ppm or less, for example, about 17,000 ppm or less, for example, about 16,000 ppm or less, for example, about 100 to 15,500 ppm, for example, about 150 to 15,000 ppm. In one embodiment, the reduced ionic component concentration can be, for example, greater than 0 ppm, for example, greater than 10 ppm, for example, greater than 20 ppm, or for example, greater than 50 ppm.

[0038] Step 8: Increasing the concentration of 3-HP in the fermentation broth The method for obtaining the compound of the present invention may include a step of increasing the concentration of 3-HP in a fermentation broth with reduced ionic components. In this case, the fermentation broth in step 8 may be a treatment broth that has undergone step 2 and / or step 3. Alternatively, the fermentation broth in step 8 may be a treatment broth that has undergone step 2 and / or step 3, and then one or more of steps 4 to 7. In this case, the concentration of 3-HP in the treatment broth with reduced ionic components can be increased by methods such as evaporation and concentration.

[0039] In one embodiment, the fermentation broth from which other components, including 3-HP, have been removed or reduced in concentration can be evaporated and / or concentrated to increase the 3-HP concentration. In one embodiment, after steps 1 to 7, step 8 can be performed to increase the 3-HP concentration. In this case, the concentrated fermentation broth may be in the form of an aqueous solution from which most impurities, except for water, have been removed, i.e., a 3-HP solution. In this case, the 3-HP concentration of the concentrated fermentation broth in the form of an aqueous solution may be, for example, 15 wt% or more, for example, 16 wt% or more, for example, 17 wt% or more, for example, 18 wt% or more, for example, 19 wt% or more, or for example, 20 wt% or more. In this case, the 3-HP concentration of the concentrated fermentation broth in the form of an aqueous solution may be about 80 wt% or less. In this case, evaporation and concentration can be performed by applying vacuum and / or heat, and the 3-HP concentration can be adjusted by evaporating and removing water.

[0040] For example, when the fermentation liquor is distilled using vacuum distillation to increase the concentration of 3-HP, the process can be performed at an absolute pressure of about 10 to 300 mbar, e.g., about 25 to 280 mbar, e.g., about 30 to 250 mbar, e.g., about 50 to 200 mbar, e.g., about 70 to 190 mbar, e.g., about 80 to 180 mbar. In an embodiment, the process of increasing the concentration of 3-HP using vacuum distillation can be performed at a pressure of about 20 mbar or less, e.g., about 25 mbar or less, e.g., about 30 mbar or less, e.g., about 50 mbar or less, e.g., about 70 mbar or less, e.g., about 80 mbar or less. In one embodiment, the step of increasing the concentration of 3-HP using vacuum distillation can be performed at, for example, about 300 mbar or less, for example, about 280 mbar or less, for example, about 250 mbar or less, for example, about 200 mbar or less, for example, about 190 mbar or less, for example, about 180 mbar or less.

[0041] The distillation can be performed using a falling film distillation apparatus, a wiper type thin film evaporator, a thin film evaporator, a centrifugal molecular distillation apparatus, a rising thin film evaporator, or the like, but is not limited thereto. The distillation can be performed using a multi-purpose tube, and a thermal recompression or mechanical recompression process can be applied for energy efficiency.

[0042] Step 9: Recovery The method for obtaining the compound of the present invention may further include a step of recovering 3-HP from the fermentation broth. In this case, the fermentation broth in step 9 may be a treatment broth that has been subjected to step 2 and / or step 3, and then to one or more of steps 4 to 8. 3-HP can be recovered in the form of an aqueous solution.

[0043] Methods for Obtaining the Compounds of the Invention The method for obtaining the compound of the present invention can include all of the steps described above, or can include two or more selected steps, or can include three or more selected steps. The present invention also allows any of the steps described herein to be selected and performed in any order. For example, the pH concentration in the fermentation broth can be increased after filtration, or filtration can be performed after increasing the pH concentration in the fermentation broth. The present invention also allows for other steps to be performed in addition to the steps described herein.

[0044] The advantages and features of the present invention, as well as methods for achieving them, will become clearer with reference to the following examples. However, the present invention is not limited to the examples disclosed below, and may be embodied in various different forms. However, these examples are provided to fully disclose the present invention and to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims.

[0045] <Experimental Example 1> Step 2: Separation test of insoluble substances 3-HP fermentation broth was produced by batch fermentation using recombinant E. coli in a medium containing glycerol as the sole carbon source. Liquid chromatography analysis of the supernatant of the fermentation broth revealed that it contained 100 g / L of 3-HP, 0.5 g / L of 1,3-PDO, and 0.3 g / L of asthenoic acid, with glycerol present at less than 0.1 g / L.

[0046] The fermentation broth was filtered through a porous polymer membrane to separate insoluble materials, and 91% of the 3-HP was recovered from the initial fermentation broth (the amount of 3-HP in the filtered fermentation broth relative to the amount of 3-HP in the fermentation broth before filtration).

[0047] After that, about 10% of the initial volume of fermented liquid (volume-based) was added to the fermented liquid remaining after filtration, and after stirring, filtration was carried out again. This is because there was dead volume (space required to operate the equipment, the fermented liquid here was not filtered) within the filtration device, so the addition of more water and subsequent filtration processes were necessary.

[0048] As a result, the recovery rate of 3-HP was increased to 96.7% of the amount of 3-HP contained in the initial fermentation broth. In other words, after recovering 91% of the filtrate compared to the initial amount, adding a certain amount of water and then producing more filtrate increased the recovery rate of 3-HP to 96.7% (Figure 2).

[0049] <Experimental Example 2> Step 5: Confirmation of 1,3-propanediol and glycerol peaks by single column chromatography The filtered fermentation broth prepared in Experiment 1 was concentrated to produce a 30 w / w% 3-HP solution, which was used as the feed for Experiment 2. Confirmation revealed that the feed contained 3-HP in the form of a calcium salt. A 380 ml glass column was packed with cation exchange resin, and 20 ml of 30% 3-HP fermentation broth was pulse-filled using a metering pump. The ion exchange resin was passed through the column from bottom to top at 10 ml / min using DI water as the eluent. 10 ml samples were taken from the liquid passing through the column and analyzed by liquid chromatography (single column chromatography at 50°C and a space velocity of 1 h ). -1 (processed).

[0050] As a result, it was confirmed that the peaks of 1,3-PDO and glycerol were similarly formed near the tail of 3-HP (Figure 3). Therefore, it can be inferred that 3-HP can be separated from 1,3-PDO and glycerol by SMB chromatography using the repulsive force between the 3-HP salt and the resin.

[0051] Separately, SMB chromatography experiments were performed using the same ion exchange resin and a 3-inch diameter column. A 300 g / L feed of 3-HP, produced by ultrafiltration and concentration of 3-HP-containing fermentation broth, was injected into the SMB system. The feed temperature was maintained between 25 and 50°C, and the eluent (water) was injected at a ratio of 1 to 3 times (by weight) the feed. By adjusting the Extract to Raffinate flow ratio (E / R ratio) between 0.1 and 5.0, glycerol and 1,3-propanediol in the raffinate flow were removed to below 30 ppm. The 3-HP concentration in the raffinate ranged from 70 g / L to 250 g / L. Furthermore, when the residual 1,3-propanediol level was increased to 50 ppm, a recovery rate of 99.4% (the amount of 3-HP released in the raffinate relative to the amount of 3-HP injected in the feed) was achieved.

[0052] <Experimental Example 3> Step 6: Calcium ion removal test The filtered fermentation broth produced in Experimental Example 1 was concentrated to produce a 3-HP solution of approximately 20 w / v% concentration, which was used as the feed in Experimental Example 3. The feed was analyzed by ion chromatography and found to contain approximately 40,000 ppm of Ca ions and 213 g / L of 3-HP.

[0053] 1,300 g of the feed (3-HP fermentation broth) was placed in a glass beaker, and approximately 870 g of 15% sulfuric acid solution was added at a rate of 30 mL / min using a metering pump and stirred at 200 rpm. After the sulfuric acid solution was completely added, the mixture was further stirred for approximately 1 hour. The resulting white calcium sulfate particles were vacuum filtered through a 0.2 micron filter.

[0054] As a result, a filtrate containing 130 g / L of 3-HP and with a pH of 2-3, from which most of the Ca ions had been removed, was obtained. Approximately 290 g of wet white solid matter remained on top of the filter paper. This white solid matter was gypsum, with a moisture content of approximately 40% by weight or more.

[0055] The progress of the precipitation reaction was confirmed by monitoring pH and electrical conductivity. After the precipitation process was completed, the calcium ion concentration in the filtrate was confirmed to be below 500 ppm (Figure 4).

[0056] <Experimental Example 4> Step 7: Ion exchange test In Experimental Example 3, the 3-HP in the fermentation broth with a lowered pH exists in the form of an undissociated acid, and residual ions in the fermentation broth can be further removed by ion exchange resin treatment. The filtered fermentation broth produced in Experimental Example 1 was subjected to sulfuric acid reaction to remove calcium, as in Experimental Example 3, to prepare a feed with an ion content of approximately 16,600 ppm, which was used as the feed for Experimental Example 4. When 250 mL of feed was injected and passed through 65 mL of cation exchange resin and 40 mL of anion exchange resin at a flow rate of 5 mL / min, 3-HP and other undissociated organic acids passed through the ion exchange resin, resulting in a final ion concentration of approximately 200 ppm (Figure 5). Therefore, due to the amount of water added to recover 3-HP during the ion exchange resin pass, the 3-HP concentration initially decreased from 125 g / L to 75 g / L. Even considering this, it was confirmed that 98% of the ions in the feed could be removed (Figure 6).

[0057] There were ions that were not removed by the single-stage ion exchange, which involved passing the cation and anion exchange resins once, but these ions were divalent cations (Mg, Ca) and potassium, which could be removed by further treatment with a small amount of cation exchange resin.

[0058] <Experimental Example 5> Step 7: Electrodialysis test The filtered fermentation broth produced in Experimental Example 1 was subjected to the same treatment process as Experimental Example 3 and used as the feed in Experimental Example 5. The ion content in the feed was approximately 16,600 ppm. Because the concentration of the ions to be treated was 3,000 ppm or higher, it was preferable to remove the main ion components by applying electrodialysis or SMB chromatography in order to efficiently remove the ion components. Although the ion components in the fermentation broth can be removed by only one of the processes of electrodialysis, ion exchange, and SMB chromatography, it was expected that a combination of two or more processes would be advantageous in terms of reducing wastewater generation and operating costs and increasing the efficiency of ion removal.

[0059] One liter of feed containing approximately 16,600 ppm of these ions was electrodialyzed using a heterogeneous ion exchange membrane (10 sets: 10 alternating layers of cation and anion exchange membranes) to remove ionic substances remaining in the fermentation broth. The fermentation broth flowed between the cation and anion exchange membranes at a flow rate of 0.6 GPM (2.27 LPM). A voltage of 8 V was applied between the ion exchange membranes. Changes in the amount of ions in the fermentation broth were observed from changes in the fermentation broth's electrical conductivity. After 4 hours of dialysis, the electrical conductivity of the fermentation broth decreased from 21.37 mS / cm to 1.35 mS / cm. This confirmed that approximately 95% of the ions were removed (Figure 7). [Industrial Applicability]

[0060] The present invention relates to a method for obtaining a compound of interest by removing at least a portion of insoluble substances or macromolecules from a fermentation broth, and then recovering the compound of interest by carrying out one or more of the following steps (a) to (c): (a) increasing the concentration of the compound of interest in the fermentation broth; (b) reducing the concentration of residual carbon sources or alcohols in the fermentation broth; (c) A step of reducing the concentration of ionic components in the fermentation broth.

Claims

1. A method for obtaining a compound by removing at least a portion of insoluble substances or macromolecules from a fermentation broth obtained using glycerol as a carbon source, and then recovering a target compound by carrying out at least step (b) of the following steps (a) to (c): (a) increasing the concentration of the compound of interest in the fermentation broth (b) reducing the concentration of at least the alcohol among the residual carbon source and alcohol in the fermentation liquid, wherein the alcohol is 1,3-propanediol; (c) A step of reducing the concentration of ionic components in the fermentation liquid.

2. The method according to claim 1, wherein any one or more of the steps (a) to (c) above is repeated two or more times.

3. 2. The method of claim 1, wherein step (a) is carried out by one or more selected from the group consisting of evaporation, concentration, and distillation.

4. The method according to claim 1, wherein the step (c) is carried out by the following (c)' or (c)'': (c)': A step of treating the fermentation liquid with an acid to precipitate ionic components and then removing them. (c)″: A step of treating the fermentation liquid with one or more methods selected from the group consisting of electrodialysis, ion exchange, and chromatography.

5. The chromatography in (c)'' was carried out by SMB (Simulated Moving Mixture).

5. The method according to claim 4, characterized in that it is a Bed chromatography.

6. The method of claim 1 , wherein the insoluble material comprises cells.

7. 2. The method of claim 1, wherein the macromolecule is a protein, a polysaccharide, or a lipid.

8. 2. The method of claim 1, wherein the target compound is an organic acid produced by microbial fermentation.

9. 2. The method of claim 1, wherein the residual carbon source in (b) is glycerol.

10. 2. The method according to claim 1, wherein the alcohol in (b) is an alcohol produced by microbial fermentation.

11. The method according to claim 1, wherein the step (b) is carried out by applying the fermentation broth to SMB (Simulated Moving Bed) chromatography.

12. A method for producing a compound, comprising: removing at least a portion of insoluble substances or macromolecules from a fermentation broth obtained using glycerol as a carbon source; (a) increasing the concentration of a target compound in the fermentation broth; (b) reducing the concentration of at least the alcohol among the remaining carbon sources and alcohols in the fermentation broth, the alcohol being 1,3-propanediol; (c)': treating the fermentation broth with an acid to precipitate ionic components, which are then removed; and (c)'': treating the fermentation broth with one or more methods selected from the group consisting of electrodialysis, ion exchange, and chromatography; (a) increasing the concentration of the target compound in the fermentation broth, and then recovering the target compound to obtain the compound. The method of claim 1.

Images