Patent Application
20120107920
The present invention relates to a sugar solution producing method and a saccharification device for producing a sugar solution through a reaction between enzyme and biomass containing cellulose.
In recent years, in order to obtain a substitution energy source for oil resources, there has been considered a method of producing alcohol by producing a sugar solution from biomass such as a woody or herbaceous material, for example, wood chips, rice straws, and so on with the use of enzyme and fermenting sugar of the sugar solution, as shown in Patent Document 1, for instance. Main components of the biomass of these kinds are: lignin which is an aromatic compound and has a three-dimensional structure; and cellulose and hemicellulose each being a sugar polymer. The cellulose and hemicellulose are hydrolyzed by the enzyme into a monosaccharide that will be a raw material for alcohol fermentation. However, the cellulose and the hemicellulose are protected by the lignin, and therefore, as shown in
As a concrete device for performing this process, used is a device, as shown in
In order to perform such a process as actual business on a payable basis, a great cost reduction is required, which involves the following problems. Firstly, for example, because the enzyme used to produce the sugar solution is very expensive, its efficient use by the recovery and reuse is necessary without discarding the enzyme every time the reaction is finished. For example, the above-described device is capable of collect the enzyme by, for example, membrane separation after the enzyme causes the reaction of the biomass in the saccharification tank 101, but in this case, the lifetime of the membrane becomes short because the membrane becomes dirty, which leads to a cost increase. Further, by the membrane separation, the enzyme adsorbed to a cracked residue of the biomass cannot be recovered. Therefore, a study to find a method for low-cost reuse of the enzyme as well as consumables such as this membrane is needed.
Further, in order to reduce an amount of the unreacted biomass discarded as the residue to reduce the waste of the raw material, it is necessary to make a ratio of the sugar solution produced from the supplied biomass (saccharification ratio: weight of generated sugar/weight of cellulose and hemicellulose in biomass) as high as possible. At this time, in the aforesaid enzymatic reaction, the presence of the sugar inhibits an enzymatic decomposition reaction, which gives rise to a problem that a reaction rate decreases as a sugar concentration increases in accordance with the progress of the reaction. Further, in the biomass, a portion that is easily enzymatically decomposed, such as, for example, an amorphous portion in the cellulose and a portion that is not easily decomposed such as, for example, a portion having high crystallinity in the cellulose are both present. In the enzymatic reaction of the biomass, it is thought that the decomposition first progresses in its easily decomposed portion, and it is thought that as the reaction progresses, a reaction rate further decreases because an amount of the easily decomposed portion reduces.
Therefore, if under a condition where the sugar concentration is high, an effort is made to make the cellulose and the hemicellulose react completely or almost completely for the purpose of increasing the saccharification ratio, the reaction takes many days and the running time of the device increases contrary to the intension, leading to a cost increase. Further, an effort to increase the saccharification ratio by supplying a large amount of the enzyme leads to a cost increase unless the enzyme is recovered for reuse.
Another possible method to increase the saccharification ratio is, for example, to reduce the sugar concentration by reducing a charge amount of the biomass into the reaction tank 101, thereby reducing an amount of the residue without requiring many days for the reaction, but in this case, since the concentration of the obtained sugar solution becomes low, the concentration of the fermentation ethanol also decreases. Accordingly, an energy amount required for the distillation at the time of the production of the condensed ethanol being an end product increases and an installed capacity becomes large. Furthermore, in order to produce the sugar solution low in sugar concentration, the saccharification tank 101 and the enzymatic reaction tank 102 need to be large, which leads to a cost increase. Therefore, it is very difficult to increase the saccharification ratio at low cost without spending many days for the reaction.
Under such circumstances, there has been studied a method in which the enzymatic reaction and the ethanol fermentation both take place in the same reaction tank 103 as shown in
Further, in order to obtain the ethanol from the biomass at low cost by the above-described enzymatic method, it is desirable to produce the sugar solution being a precursor of the ethanol so that it has as high concentration as possible, for the purpose of, for instance, reducing energy required for condensing the ethanol, but it is extremely difficult to obtain the high-concentration sugar solution due to the sugar inhibition, or because the biomass low in reactivity remains in a terminal period of the reaction as described above. It is known that a high-concentration sugar solution can be obtained by, for example, increasing a supply amount of the enzyme and a charge amount of the biomass in the reaction tank 101, but in this method, an amount of the used enzyme increases and further an amount of the unreacted residue increases, leading to a high cost.
Patent Document 2 describes an art in which, in concurrent saccharification-fermentation reactions where cellulose is turned into ethanol, a liquid part including enzyme and alcohol is brought into contact with a solid including the cellulose contributing to the concurrent saccharification-enzymatic reactions, whereby the enzyme is adsorbed to the solid, but this method does not consider the production of a high-concentration sugar solution.
The present invention was made under such circumstances, and has an object to provide a sugar solution producing method and a saccharification device that make it possible to obtain a high-concentration sugar solution at low cost when obtaining a sugar solution through a reaction between enzyme and biomass including cellulose.
A method of producing a sugar solution of the present invention is a method to obtain a sugar solution through a reaction of cellulose-based biomass being an aggregate of plants or an aggregate of processed products of plant including cellulose with a saccharifying enzyme having cellulose saccharifying ability, the method including:
a first reaction step of mixing a saccharifying enzyme and cellulose-based biomass in an aqueous solution to cause a saccharification of the biomass by the saccharifying enzyme;
a first separation step of causing solid-liquid separation of a reaction solution obtained in the first reaction step to obtain a sugar solution and a residue; and
a second reaction step of preparing an aqueous solution by adding additive water to the residue obtained in the first separation step, and in the aqueous solution, causing a saccharification of the residue by the saccharifying enzyme adsorbed to the residue; and
a third reaction step of adding cellulose-based biomass not having undergone the saccharification to the sugar solution obtained in the first separation step and causing a saccharification of the newly added biomass by the saccharifying enzyme present in the sugar solution.
Different reaction tanks are preferably used for the first reaction step, the second reaction step, and the third reaction step.
Preferably, the method includes:
a second separation step of causing solid-liquid separation of a reaction solution obtained in the second reaction step to obtain a sugar solution and a residue;
a third separation step of causing solid-liquid separation of a reaction solution obtained in the third reaction step to obtain a high-concentration sugar solution and a residue; and
a reaction step of mixing the sugar solution obtained in the second separation step and the residue obtained in the third separation step to cause a saccharification,
wherein the reaction step corresponds to the first reaction step, and the biomass used in the first reaction step is the residue obtained in the third separation step.
Preferably, the method further includes a step of additionally supplying a saccharifying enzyme to at least one of the aqueous solution in the second reaction step and the sugar solution separated in the second separation step.
Preferably, a ratio of lignin contained in the biomass is 10% or less.
A saccharification device of the present invention is a saccharification device for carrying out the above-described method of producing the sugar solution, the device including:
two reaction tanks in each of which a saccharifying enzyme and a cellulose-based biomass are mixed in an aqueous solution and a saccharification of the biomass is caused by the saccharifying enzyme;
a biomass supply part to supply the biomass into the reaction tanks;
a first enzyme supply part to supply the saccharifying enzyme into the reaction tanks;
an additive water supply part to supply additive water into one reaction tank out of the two reaction tanks;
a first separating part to perform solid-liquid separation of a reaction solution generated by the reaction between the biomass and the saccharifying enzyme in the one reaction tank to obtain the sugar solution and the residue;
a first transfer part to transfer the sugar solution separated by the first separating part to the other reaction tank out of the two reaction tanks; and
a control part that outputs a control signal so that the first reaction step is performed in the one reaction tank, the sugar solution obtained by the first separating part is next supplied to the other reaction tank, thereafter the additive water and cellulose-based biomass not having undergone the saccharification are supplied into the reaction tank storing the residue and the reaction tank storing the sugar solution respectively, and the second reaction step and the third reaction step are performed in the two reaction tanks respectively.
The first enzyme supply part may supply the saccharifying enzyme into the one reaction tank instead of the two reaction tanks,
the additive water supply part may supply the additive water into the other reaction tank instead of the one reaction tank,
the first transfer part may transfer the residue instead of the sugar solution to the other reaction tank, and
the control part may output the control signal so that after the first reaction step is performed, the other reaction tank is supplied with the residue obtained by the first separating part instead the sugar solution obtained by the first separating part.
The first separating part may separate the sugar solution and the residue by sedimentation in the one reaction tank.
A saccharification device of the present invention is a saccharification device for carrying out the method of producing the sugar solution described above, the device including:
a first reaction tank, a second reaction tank, and a third reaction tank in each of which a saccharifying enzyme and a cellulose-based biomass are mixed in an aqueous solution and a saccharification of the biomass is caused by the saccharifying enzyme;
biomass supply parts to supply the biomass to the first reaction tank and the third reaction tank respectively;
an enzyme supply part to supply the saccharifying enzyme into the first reaction tank;
an additive water supply part to supply additive water into the second reaction tank;
a first separating part to perform solid-liquid separation of a reaction solution obtained by the reaction between the saccharifying enzyme and the biomass in the first reaction tank to obtain a sugar solution and a residue;
a first sugar solution supply part and a first residue supply part to supply the sugar solution and the residue separated by the first separating part to the third reaction tank and the second reaction tank respectively; and
a control part that outputs a control signal so that the first reaction step is performed in the first reaction tank, next, the residue and the sugar solution are separated by the first separating part from the reaction solution obtained in the first reaction tank, the residue and the sugar solution are supplied to the second reaction tank and the third reaction tank respectively, and thereafter, the additive water and cellulose-based biomass not having undergone the saccharification are supplied to the second reaction tank and the third reaction tank respectively, and the second reaction step and the third reaction step are performed in the reaction tanks respectively.
Preferably, the device includes:
a second separating part to perform solid-liquid separation of a reaction solution generated in the second reaction tank to obtain a sugar solution and a residue;
a third separating part to perform solid-liquid separation of a reaction solution generated in the third reaction tank to obtain a high-concentration sugar solution and a residue;
a second sugar solution supply part to supply the first reaction tank with the sugar solution separated in the second separating part;
a third residue supply part to supply the first reaction tank with the residue separated in the third separating part; and
a sugar solution collecting part to take out the high-concentration sugar solution separated in the third separating part,
wherein there is performed a step of obtaining a sugar solution and a residue from a reaction solution obtained in the second reaction tank, by using the second separating part, obtaining a high-concentration sugar solution and a residue from a reaction solution obtained in the third reaction tank, by using the third separating part, and making the sugar solution separated in the second separating part react in the first reaction tank with the residue separated in the third separating part, and
wherein the step corresponds to the first reaction step, and the biomass used in the first reaction step is the residue separated in the second separating part.
The first separating part, the second separating part, and the third separating part may separate the sugar solution and the residue by sedimentation in the first reaction tank, the second reaction tank, and the third reaction tank respectively.
Preferably, the biomass is subjected to a pretreatment operation by an appropriate method, and a ratio of lignin contained in the biomass is 10% or less, or the biomass is a processed product of a plant material with a high cellulose content ratio and a low lignin content ratio, such as used paper, pulp, cotton, or cotton fiber.
In the present invention, in obtaining a high-concentration sugar solution through a reaction between enzyme and biomass including cellulose, a sugar solution (I) and a residue (I) including unreacted biomass by which the enzyme is adsorbed are generated through a reaction between the biomass and the enzyme, next, the sugar solution (I) and the residue (I) are separated, a pH adjusting solution is supplied to the residue (I), and through a reaction between the residue (I) and the enzyme adsorbed to the residue (I), a sugar solution (II) is generated. Further, new biomass is supplied to the sugar solution (I), and through a reaction between the biomass and the enzyme remaining in the sugar solution (I), a sugar solution (III) and a residue (III) are generated. Further, by making the residue (III) and the sugar solution (II) react with enzyme contained in these residue (III) and sugar solution (II), a monosaccharide is further produced. This enables the effective use of the enzyme to reduce an amount of the discarded residue, which makes it possible to obtain a high-concentration sugar solution at low cost.
(Device Structure of First Embodiment)
A first embodiment of a sugar solution producing device for performing a sugar solution producing method of the present invention will be described with reference to
The reaction tanks 10 are each provided with a heater for keeping a reaction solution therein at a reaction temperature of, for example, about 50° C. to 60° C., a thermocouple for measuring the temperature of the reaction solution, and so on (none is shown). Further, in the drawing, a screw-type agitator is shown, but this does not limit the type of the agitator. For convenience sake, the reaction tank 10 at the center, the reaction tank 10 on the left, and the reaction tank 10 on the right in
In
A first sugar solution supply path 51 and a first residue supply path 52 for supplying the sugar solution and the residue separated in the separator 31 to the third reaction tank 23 and the second reaction tank 22 respectively are connected as a first sugar solution supply part and a first residue supply part to the first separator 31. Further, a second sugar solution supply path 53 being a second sugar solution supply part for supplying the first reaction tank 21 with the sugar solution separated in the separator 32 and a residue discharge path 54 for discarding the residue separated in the second separator 32, to the outside of the system are connected to the second separator 32. The residue discharged from the residue discharge path 54 is lignin 3 and so on contained in the biomass, and is, for example, burned so that thermal energy is recovered. A third residue supply path 55 supplying the first reaction tank 21 with the residue separated in the separator 33 and a sugar solution recovery path 56 taking the sugar solution separated in the separator 33 to the outside are connected as a third residue supply part and a sugar solution collecting part respectively to the third separator 33, and the sugar solution recovered from the sugar solution recovery path 56 is used as a raw material of a chemical product, or is fermented by a fermentative microorganism in a not-shown fermentation tank to turn into alcohol, for example, an ethanol solution. Then, this ethanol solution is thereafter condensed (distilled) for refinery. The above separators 31 to 33 are equipped with not-shown valves, which can allow/stop the supply of the residue and the sugar solution discharged from these separators 31 to 33.
(Regarding Biomass and Enzyme)
The biomass supplied to the first reaction tank 21 and the third reaction tank 23 is woody or herbaceous biomass whose lignin is broken or melted and removed by appropriate pretreatment. A method of the pretreatment is, for example, dilute sulfuric acid decomposition, steam explosion, ammonia explosion, supercritical ammonia treatment, hydrothermal/supercritical water treatment, biodegradation, pulverization, or chemical treatment. A content of the lignin in the biomass is, for example, 10% or less, preferably 5% or less. Further, other than the biomass having undergone the pretreatment, plant processed products such as used paper, pulp, cotton, and cotton fiber also become the biomass to be processed.
The enzyme supplied to the first reaction tank 21 is a cellulose decomposing enzyme or a hemicellulose decomposing enzyme, and is a particle (solid) with about several tens Å. Further, as shown in
(Result of Experiment in Example and Study)
Next, a reason why the concentration of the sugar contained in the sugar solution taken to the outside is high, an amount of the residue discharged to the outside is small, and an amount of the enzyme discharged together with the sugar solution and the residue to the outside is reduced in the above-described device, compared with the aforesaid device shown in
Further, from the above result in
Therefore, when the foregoing results in
Next, as described above, the sugar solution obtained through the decomposition of the biomass is thereafter turned into ethanol by fermentation, and thereafter is condensed by, for example, distillation. Therefore, for the low-cost production of ethanol being an end product, a reduction in energy required for the condensation is required. Therefore, the concentration of the sugar contained in the sugar solution is desirably increased as much as possible. In order to increase the sugar concentration in the sugar solution without spending a long reaction time, an increase of an addition amount of the enzyme is necessary. However, increasing the addition amount of the enzyme results in higher production cost because in a conventional enzyme saccharification method, the expensive enzyme is discarded when it is once used. As a solution to this, there has been proposed an enzyme recovery method using a separation membrane, but this method needs a great facility expense for the separation membrane. Therefore, in the present invention, the following experiments and studies were conducted in order to configure a measure that can efficiently collect and reuse the added enzyme by a simple method even if an addition amount of the enzyme is increased in order to obtain a high-concentration sugar solution, can make this operation contribute to an increase in the concentration of the sugar solution, and can reduce an amount of the discarded residue.
Here, when the new biomass is added, a method in which the residue and the sugar solution are not separated and the new biomass is added to them is also conceivable, instead of separating the residue and the sugar solution and adding the new biomass to this sugar solution. An experiment where new biomass is added 50 hours later from the start of the reaction without separating the sugar solution from the residue and the sugar concentration and the saccharification ratio are measured will be described with reference to
However, when the biomass is newly added without separating the residue and the sugar solution as shown in
(Operation of First Embodiment)
Based on the flow of the whole reaction shown in
First, as shown in
Further, as shown in
Meanwhile, in the third reaction tank 23, the enzyme contained in the sugar solution generated in the first reaction tank 21 is adsorbed to the added biomass, so that an enzyme concentration in a reaction solution quickly decreases. Then, in this third reaction tank 23, the sugar inhibition strongly works due to the sugar solution supplied from the first reaction tank 21, but an easily reacting portion in the newly added biomass is quickly decomposed by the enzyme in the sugar solution as previously described, so that a high-concentration sugar solution is generated. Subsequently, as shown in
Meanwhile, in the third reaction tank 23, as a third separation step, an obtained high-concentration sugar solution and a residue are separated in the third separator 33, the high-concentration sugar solution is discharged to the outside of the system and the residue is supplied to the first reaction tank 21 (Step S42). The high-concentration sugar solution is discharged to the outside of the system together with the enzyme contained in the high-concentration sugar solution, but since most (about 60% from the aforesaid result in
Subsequently, in the first reaction tank 21, a reaction solution whose sugar concentration is lower than that of the high-concentration sugar solution obtained in the third reaction tank 23 is prepared from the sugar solution supplied from the second reaction tank 22 and the residue supplied from the third reaction tank 23 as shown in
Thereafter, a sugar solution and a residue which are obtained in the first reaction tank 21 are supplied to the third reaction tank 23 and the second reaction tank 22 respectively, and the above-described Step S2 to Step S5 are repeated. Specifically, as shown in
Then, in the reaction tanks 10, reaction solutions different in sugar concentration are prepared respectively as previously described, that is, as shown in
Part of the enzyme supplied to the first reaction tank 21 is adsorbed to the residue to be discharged from the second reaction tank 22 to the outside of the system and some other part thereof is discharged to the outside of the system from the third reaction tank 23 together with the high-concentration sugar solution, but by adjusting operation conditions in the respective reaction tanks 10 so that an amount of the generated residue becomes small in the second reaction tank 22 and an amount of the enzyme adsorbed to the residue and returned to the first reaction tank 21 becomes large in the third reaction tank 23, the enzyme, so to speak, circulates among the three reaction tanks 10 as shown in
At this time, since the enzyme is also discharged to the outside of the system, though only slightly, and since the enzyme sometimes becomes deactivated by the decomposition reaction of the biomass, the enzyme is additionally supplied to the first reaction tank 21 in these cases as shown in
Here, when the above steps are automated, a not-shown control part is provided in this saccharification device, and the control part outputs a control signal to the saccharification device so that the aforesaid allowance/stop of the supply by the not-shown valve and the agitating and heating of the reaction solutions in the reaction tanks 21 to 23 are performed in order for the above-described steps to be performed.
According to the above-described embodiment, in obtaining the sugar solution through the reaction of the enzyme and the biomass containing cellulose, the sugar solution in which the enzyme is dispersed and the residue containing the unreacted biomass adsorbing the enzyme are generated through the reaction of the biomass and the enzyme in the first reaction tank 21, next, these sugar solution and residue are separated, and the pH adjusting solution is supplied to the residue in the second reaction tank 22, whereby the dilute solution whose sugar concentration is lower than that of the aforesaid sugar solution is prepared, and the residue and the enzyme adsorbed to the residue are made to react in this dilute solution, whereby the sugar solution is obtained. Therefore, it is possible to efficiently use and collect the enzyme and also to reduce an amount of the discarded residue (obtain a high saccharification ratio), which makes it possible to obtain the sugar solution at low cost. Further, since the recovery and reuse of the enzyme are achieved, it is possible to, for example, increase an amount of the supplied enzyme, in which case the sugar solution can be obtained in a short time.
Further, in the third reaction tank 23, by further adding the biomass to the sugar solution which has been separated from the residue, it is possible for the enzyme dispersed in the sugar solution to react with the easily decomposed portion in the newly added biomass, which enables efficient use of the enzyme and makes it possible to quickly increase the sugar concentration in the sugar solution. Furthermore, it is possible to collect the enzyme dispersed in the sugar solution by the residue of the newly added biomass adsorbing it. Achieving the production of the sugar solution with a high sugar concentration and a reduction in an amount of the discharged enzyme allow each of the reaction tanks 10 to be small, enabling a reduction in facility expense, can reduce energy required for the later distillation, and further can reduce the expense for the enzyme, which makes it possible to obtain the sugar solution and ethanol at low cost. At this time, since the residue generated in the first reaction tank 21 is separated in advance before the biomass is added to the third reaction tank 23, the decomposition ratio of the residue generated in the third reaction tank 23 can be uniform, and accordingly, the residue can be efficiently decomposed in the first reaction tank 21 and the second reaction tank 22 to which the residue is sequentially supplied thereafter.
Then, since the sugar solution and the residue generated in the second reaction tank 22 and the third reaction tank 23 respectively are returned again to the first reaction tank 21, it is possible to continuously obtain the high-concentration sugar solutions by making an effective use of these sugar solution and residue and to reduce amounts of the discarded residue and enzyme. Further, the use of the three reaction tanks 10 for the above-described processes enables the efficient performance of the processes. Further, in circulating (reusing) the enzyme in the three reaction tanks 10, no consumables such as, for example, a membrane, is not used, it is possible to obtain the high-concentration sugar solution at low cost.
Further, in the second reaction tank 22, the enzyme is discharged to the outside of the system together with the residue, but since this residue is mainly lignin, by making a content of the lignin in the supplied biomass small in advance as previously described, it is possible to reduce an amount of the enzyme discharged together with the residue.
In additionally supplying the enzyme at the aforesaid Step S6, the enzyme is supplied to the first reaction tank 21 but it may be supplied to the second reaction tank 22.
Further, in the above-described example, the three reaction tanks 10 are provided, but the number thereof may be three or more, for example, five as shown in
Further, the separators 11 are provided for the respective reaction tanks 10, but the same separator 11 may be commonly used for the reaction tanks. Another alternative structure may be, for example, to settle down or filtrate the residue in each of the reaction tanks 10, and for example, suck a supernatant liquid to take out a deposit and a filtrated substance (residue) or leave them in the reaction tank. In this case, the reaction tanks 10 each also serve as a separating means.
Alternatively, the number of the reaction tanks 10 may be two. Such a sugar solution producing device will be described with reference to
Regarding the two reaction tanks 21, 22, for convenience sake, the left one is called a first reaction tank 21 and the right one is called a second reaction tank 22, and an enzyme supply path 41, a biomass supply path 42 (biomass adding path 44), a pH adjusting solution supply part 43, a residue discharge path 54, and a sugar solution recovery path 56 are connected to each of the reaction tanks 21, 22. In the description below, “first” is appended to the supply paths and the recovery path (the enzyme supply path 41, the biomass supply path 42 (biomass adding path 44), the pH adjusting solution supply path 43, the residue discharge path 54, and the sugar solution recovery path 56 connected to the first reaction tank 21 and “second” is appended to those connected to the second reaction tank 22. A first supply path (first transfer part) 61 and a second supply path 62 for sucking sugar solutions being supernatant liquids in the reaction tanks 21, 22 to supply them to the other reaction tanks 22, 21 are connected to the reaction tanks 21, 22.
In this sugar solution producing device, first, when enzyme, a pH adjusting solution, and biomass are supplied to the first reaction tank 21, a sugar solution and a residue are generated, as shown in
In this embodiment, the same operations and effects as those of the above-described embodiment can also be obtained.
In the above-described case, the residue is left and the sugar solution is moved to/from the reaction tanks 21, 22, but another possible structure may be, for example, to move the residue, which has been separated by sedimentation, by sucking the residue from under. In this case, the same operations and effects are also obtained.
Further, the biomass used as a raw material of the sugar solution in each of the above-described examples may be a processed product of a plant raw material, such as used paper, pulp, or cotton fiber, containing the cellulose 1, instead of a woody raw material and a herbaceous raw material, or may be comprised of a plurality of kinds of these raw materials containing the cellulose 1. The enzyme is preferably a cellulose decomposing enzyme or a combination of a cellulose decomposing enzyme and a hemicellulose decomposing enzyme. Further, in the production of the sugar solution in the above-described manner, the present invention includes a method where the sugar solution and the residue are generated through the reaction of the biomass and the enzyme outside the system in advance at an initial stage, and at the time of continuous operation, the sugar solution and the residue are supplied to the different reaction tanks 10 respectively and the above-described processes are performed.
Next, regarding the results of the various experiments already described in detail, conditions, brief results, and so on of the experiments will be described below.
(experiment condition)
substrate (biomass): filter paper 10 g
enzyme: 5 ml
buffer solution: 95 ml
(experiment result)
A decomposition rate (an increasing rate of the sugar concentration) decreased with time.
(experiment condition)
substrate (biomass): filter paper
charge amount of substrate: 10 g, 25 g, 30 g, 35 g, 40 g
enzyme: 5 ml
buffer solution: 95 ml
reaction temperature: 50°
(experiment result)
As the charge amount of the raw material increased, the saccharification ratio decreased.
(experiment condition)
substrate (biomass): filter paper 10 g
enzyme: 5 ml
buffer solution: 95 ml
(experiment result)
When the biomass was supplied to the enzyme solution, the concentration of the enzyme (protein) in a solution decreased.
(experiment condition)
substrate (biomass): filter paper 10 g
enzyme: 5 ml
pH adjusting solution: 95 ml
(experiment result)
When the biomass was supplied to the enzyme solution, the enzyme was adsorbed to the biomass and accordingly an amount of the enzyme in the solution decreased, but in a short time thereafter, the enzyme adsorbed to the biomass decomposed to return again into the solution.
(experiment condition)
substrate (biomass): a residue generated under the following residue generation condition and centrifuged 16 g (wet state)
reaction solution: the above residue+buffer solution 50 ml
(experiment result)
The decomposition reaction of even the residue whose decomposition reaction did not easily progress progressed quickly when it was separated from a sugar solution whose sugar concentration became high and supplied into a low sugar concentration solution.
(experiment condition)
substrate (biomass): a residue obtained through centrifugal separation of the reaction solution 6 days later from the start of the reaction in the experiment in
reaction solution: the above residue+buffer solution 100 ml
(experiment result)
The decomposition reaction of even the residue whose decomposition reaction did not easily progress similarly progressed quickly in the low sugar concentration solution.
(experiment condition)
substrate (biomass): filter paper 10 g
reaction solution: a sugar solution obtained through centrifugal separation of the reaction solution six days later from the start of the experiment in the experiment under the same condition as that in
(experiment result)
When the biomass was supplied to the sugar solution whose decomposition reaction was delayed due to the occurrence of the sugar inhibition, the enzyme (protein) concentration in the sugar solution decreased.
(experiment condition)
substrate (biomass): filter paper 10 g
reaction solution: a sugar solution obtained through centrifugal separation of the reaction solution one day later from the start of the experiment in the experiment under the same condition as that in
(experiment result)
Even in a sugar solution whose sugar concentration became high to such a degree as to make the decomposition reaction difficult to progress due to the sugar inhibition, the biomass was quickly decomposed and the sugar concentration increased when the biomass was newly supplied.
(experiment condition)
substrate (biomass): filter paper 10 g
reaction solution: a sugar solution obtained through centrifugal separation of the reaction solution six days later from the start of the experiment in the experiment under the same condition as that in
(experiment result)
As in the above experiment, even in a sugar solution whose sugar concentration became high, the biomass was quickly decomposed and the sugar concentration increased when the biomass was newly supplied.
(experiment condition)
substrate (biomass): filter paper
substrate concentration: 10 weight/vol %
enzyme: 5 vol %
pH adjusting solution: 50 mM acetic acid buffer solution pH5
reaction temperature 50° C.
(experiment result)
When a 10 weight/vol % filter paper was newly added 50 h later from the start of the experiment, the sugar concentration whose increasing rate became low before the addition quickly increased.
(experiment condition)
substrate (biomass): filter paper
substrate concentration: 10 weight/vol %
enzyme: 5 vol %
pH adjusting solution: 50 mM acetic acid buffer solution pH5
reaction temperature: 50° C.
(experiment result)
When a 10 weight/vol % filter paper was newly added 50 h later from the start of the experiment, the saccharification ratio of the biomass after the addition was lower than that before the addition.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-169527 | Jul 2009 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2010/004608 | 7/15/2010 | WO | 00 | 1/9/2012 |
