Appetite enhancer for abalone or sea urchin, promoter for synthesis of neuropeptide y in abalone or sea urchin, and method for producing the same

Abstract

To provide a novel appetite enhancer for abalone and sea urchin derived from biomass.SOLUTION: Provided is an abalone or sea urchin appetite enhancer comprising g an extract derived from bagasse as an active ingredient.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an appetite stimulant for abalone or sea urchin, an agent for promoting the synthesis of neuropeptide Y in abalone or sea urchin, and methods for producing the same. [Background technology]

[0002] From the viewpoint of reducing the environmental load, effective use of biomass has been attracting attention. As a method of utilizing biomass, use as fuel such as bioethanol, use as functional materials such as bioplastics, and use as animal feed are being considered. For example, Patent Document 1 describes that by blending kraft pulp, a feed material capable of promoting rumination in ruminants can be obtained. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-201375 A Summary of the Invention [Problem to be solved by the invention]

[0004] As disclosed in Patent Document 1, although the use of biomass as feed for livestock animals has been considered, the use of biomass as feed for aquatic organisms has not yet been fully considered. In addition, in terms of the aquatic organisms' aquaculture, it is very important that the feed given to the aquatic organisms stimulates their appetite.

[0005] One aspect of the present invention aims to provide a novel appetite stimulant for abalone and sea urchin, which uses a component derived from biomass. [Means for solving the problem]

[0006] The present inventors have discovered that an extract derived from bagasse has the effect of promoting the synthesis of neuropeptide Y, which has a role in promoting feeding behavior in abalone or sea urchin, and can be used to increase appetite, thereby completing the present invention.

[0007] That is, one aspect of the present invention provides an appetite stimulant for abalone or sea urchin, which contains an extract derived from bagasse as an active ingredient.

[0008] Another aspect of the present invention provides an agent for promoting neuropeptide Y synthesis in abalone or sea urchin, comprising an extract derived from bagasse as an active ingredient.

[0009] The extract derived from bagasse is preferably a solid obtained by decomposing bagasse by at least one treatment selected from the group consisting of an alkali treatment, a hydrothermal treatment, an acid treatment, and a subcritical water treatment to obtain a decomposition treatment liquid, adjusting the pH of the decomposition treatment liquid to an acidic state, and then filtering the decomposition treatment liquid.

[0010] Diatomaceous earth may be added to the digestion solution prior to filtration.

[0011] Yet another aspect of the present invention provides a method for producing an appetite stimulant for abalone or sea urchin, comprising the steps of decomposing bagasse by at least one treatment selected from the group consisting of an alkali treatment, a hydrothermal treatment, an acid treatment, and a subcritical water treatment to obtain a decomposition treatment liquid, adjusting the pH of the decomposition treatment liquid to an acidic value, and then filtering the liquid to obtain a solid matter.

[0012] Yet another aspect of the present invention provides a method for producing a promoter for neuropeptide Y synthesis in abalone or sea urchin, comprising the steps of decomposing bagasse by at least one treatment selected from the group consisting of alkali treatment, hydrothermal treatment, acid treatment, and subcritical water treatment to obtain a decomposition treatment liquid, adjusting the pH of the decomposition treatment liquid to an acidic value, and then filtering the liquid to obtain a solid matter. Effect of the Invention

[0013] According to one aspect of the present invention, it is possible to provide a novel appetite stimulant for abalone and sea urchin, which uses a component derived from biomass. [Brief description of the drawings]

[0014] [Figure 1] 1 is a graph showing the effect of an extract derived from bagasse on the expression level of mRNA for neuropeptide Y in juvenile Hokkaido abalone, where (a) is the result for juvenile oysters weighing 5.4 g, and (b) is the result for juvenile oysters weighing 3.2 g. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described, however, the present invention is not limited to the following embodiment.

[0016] The appetite enhancer for abalone or sea urchin of the present invention has the effect of enhancing the appetite of abalone or sea urchin (including young shellfish or young sea urchins). The appetite enhancing effect is mainly based on the effect of increasing the expression level of mRNA for synthesizing neuropeptide Y, which is present in cerebral ganglia and plays a role in promoting feeding behavior. That is, another aspect of the present invention can be said to provide an agent for promoting the synthesis of neuropeptide Y in abalone or sea urchin, which contains an extract derived from bagasse as an active ingredient. Alternatively, it can be said to provide an agent for enhancing the expression level of neuropeptide Y mRNA in abalone or sea urchin.

[0017] In the present invention, the type of abalone or sea urchin to be the subject of appetite enhancement is not limited. For example, the abalone may be a shellfish belonging to the family Haliotis, such as Ezo abalone, Kuro abalone, Madaka abalone, or Megai abalone. The sea urchin may be an echinoderm belonging to the class Echinoids, such as the red sea urchin, the Ezo bafun sea urchin, the northern purple sea urchin, the red sea urchin, the purple sea urchin, or the white-bearded sea urchin.

[0018] An appetite stimulant for abalone or sea urchin according to one embodiment contains an extract derived from bagasse as an active ingredient.

[0019] "Bagasse" refers to the residue after squeezing sugarcane juice, typically the residue discharged in the sugar manufacturing process in the raw sugar manufacturing process. A suitable bagasse is bagasse discharged after squeezing the sugar juice in the squeezing process in a raw sugar factory. The bagasse discharged in the sugar manufacturing process in a raw sugar factory includes not only the final bagasse that leaves the final squeezing machine, but also shredded sugarcane that is eaten up by the squeezing machines after the first squeezing machine. The moisture, sugar content, and composition ratio thereof contained in the bagasse vary depending on the type of sugarcane, harvest time, etc., but in the present invention, any of these bagasses can be used. Furthermore, in the present invention, as the raw bagasse, bagasse remaining after squeezing sugarcane discharged from, for example, a brown sugar manufacturing factory, as in the raw sugar factory, or bagasse after squeezing sugar liquid from sugarcane in a small-scale laboratory implementation can also be used.

[0020] In one embodiment, the extract derived from bagasse (hereinafter, also referred to as "bagasse extract") is a solid matter obtained by decomposing bagasse by at least one treatment selected from the group consisting of alkali treatment, hydrothermal treatment, acid treatment, and subcritical water treatment to obtain a decomposition treatment liquid, adjusting the pH of the decomposition treatment liquid to an acidic state, adding diatomaceous earth, and filtering the liquid.

[0021] That is, in order to obtain a bagasse extract, bagasse is first decomposed by at least one treatment (decomposition treatment) selected from the group consisting of an alkali treatment, a hydrothermal treatment, an acid treatment, and a subcritical water treatment to obtain a decomposition treatment liquid.

[0022] The decomposition treatment of bagasse in this specification is required to destroy part or all of the chemical structures of lignin, cellulose, and / or hemicellulose. From the viewpoint of easily obtaining a bagasse decomposition treatment liquid, the decomposition treatment is preferably an alkali treatment or a hydrothermal treatment.

[0023] The alkali treatment may be, for example, a treatment in which the bagasse is brought into contact with an alkaline solution. Examples of a method for bringing the bagasse into contact with an alkaline solution include a method in which the bagasse is sprinkled with the alkaline solution, a method in which the bagasse is immersed in the alkaline solution, etc. In the method in which the bagasse is immersed in the alkaline solution, the bagasse may be immersed while being stirred in a mixture of the bagasse and the alkaline solution.

[0024] Examples of the alkaline solution include an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution, and an aqueous ammonia solution. The alkaline solution may be one of these solutions alone or a mixture of two or more of them. The alkaline solution is preferably an aqueous sodium hydroxide solution, from the viewpoint of being inexpensive and easily usable in food manufacturing processes.

[0025] The concentration of the alkaline solution may be appropriately set depending on the type of alkaline solution used, but from the viewpoint of shortening the processing time of the decomposition treatment, it is preferably 0.1 mass% or more, more preferably 0.2 mass% or more, and even more preferably 0.3 mass% or more. From the viewpoint of improving the extraction efficiency, the concentration of the alkaline solution is preferably 10 mass% or less, more preferably 5 mass% or less, and even more preferably 1.0 mass% or less.

[0026] The alkaline solution is preferably heated. From the viewpoint of shortening the treatment time of the decomposition treatment, the temperature of the alkaline solution (liquid temperature) during the alkaline treatment is preferably 50° C. or higher, more preferably 60° C. or higher, and even more preferably 80° C. or higher. From the viewpoint of not leaving polysaccharides in the decomposition treatment liquid, the temperature of the alkaline solution is preferably 110° C. or lower, more preferably 105° C. or lower, and even more preferably 100° C. or lower.

[0027] The amount of the alkaline solution added may be 50 parts by mass or more, 100 parts by mass or more, or 1000 parts by mass or more, based on 100 parts by mass of bagasse. The treatment time in the alkaline treatment may be appropriately adjusted depending on the type, temperature and amount of the alkaline solution added, and may be, for example, 1 to 5 hours.

[0028] The alkali treatment may be carried out under normal pressure or under pressure. When pressure is applied, the pressure may be 0.1 MPa or more, or 0.2 MPa or more, and may be 4.0 MPa or less, 1.6 MPa or less, or 0.5 MPa or less.

[0029] The pH of the decomposition treatment liquid after the alkali treatment may be 8 or more, or 9 or more, and may be 13 or less, or 12 or less.

[0030] The hydrothermal treatment may be a treatment in which bagasse is brought into contact with high-temperature water or steam under high pressure. More specifically, the hydrothermal treatment may be a method in which water is added so that the solid concentration of the bagasse becomes 0.1 to 50%, and a decomposition treatment is carried out under high-temperature and high-pressure conditions. The temperature of the water or steam is preferably 130 to 250°C, and the pressure applied is preferably 0.1 to 0.5 MPa higher than the saturated steam pressure of water at each temperature.

[0031] The acid treatment may be a treatment in which the bagasse is brought into contact with an acidic solution. Examples of the acidic solution include dilute sulfuric acid and dilute hydrochloric acid. The method of the acid treatment may be a method in which the alkaline solution in the above-mentioned alkali treatment is replaced with an acidic solution. That is, the method of bringing the bagasse into contact with the acidic solution, the temperature of the acidic solution in the acid treatment, the pressure conditions in the acid treatment, etc. may be the same as the method or conditions in the above-mentioned alkali treatment.

[0032] The subcritical water treatment may be a treatment in which subcritical water is brought into contact with bagasse. The method of bringing subcritical water into contact with bagasse may be a method in which the alkaline solution in the above-mentioned alkaline treatment is replaced with subcritical water. The conditions for the subcritical water treatment are not particularly limited, but it is preferable that the temperature of the subcritical water is 160 to 240°C and the treatment time is 1 to 90 minutes.

[0033] The explosion treatment may be a treatment in which the insoluble xylan contained in the bagasse is decomposed to a certain extent by the above-mentioned hydrothermal treatment, and then the bagasse is instantaneously released to atmospheric pressure by, for example, suddenly opening a valve provided in a pressure-resistant reaction vessel, thereby pulverizing the bagasse.

[0034] After obtaining the bagasse decomposition liquid by the above-mentioned decomposition treatment, the decomposition liquid may be subjected to solid-liquid separation in order to remove insoluble components such as fiber. In this case, the liquid obtained after the separation operation can be used as the bagasse decomposition liquid. The solid-liquid separation may be performed by a method such as filtration using a strainer or a filter, centrifugation, decantation, etc.

[0035] In the decomposition treatment liquid, polymeric components such as polysaccharides may be removed by membrane separation. In this case, the liquid after membrane separation can be used as the decomposition treatment liquid. The separation membrane is not particularly limited as long as it is an ultrafiltration membrane (UF membrane). The molecular weight cutoff of the ultrafiltration membrane is preferably 2500 to 50,000, more preferably 2500 to 5,000.

[0036] Examples of materials that can be used for the ultrafiltration membrane include polyimide, polyethersulfone (PES), polysulfone (PS), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), regenerated cellulose, cellulose, cellulose ester, sulfonated polysulfone, sulfonated polyethersulfone, polyolefin, polyvinyl alcohol, polymethyl methacrylate, and polytetrafluoroethylene.

[0037] The filtration method using the ultrafiltration membrane may be dead-end filtration or cross-flow filtration, but from the viewpoint of suppressing membrane fouling, cross-flow filtration is preferred.

[0038] The membrane form of the ultrafiltration membrane may be any suitable form such as flat membrane type, spiral type, tubular type, hollow fiber type, etc. More specifically, the following may be mentioned: GE series, GH series, GK series, PW type, and HWSUF type from SUEZ Co., Ltd.; HFM-180, HFM-183, HFM-251, HFM-300, HFK-131, HFK-328, MPT-U20, MPS-U20P, and MPS-U20S from KOCH Co., Ltd.; SPE1, SPE3, SPE5, SPE10, SPE30, SPV5, SPV50, and SOW30 from Synder Co., Ltd.; Microza (registered trademark) UF series from Asahi Kasei Corporation that has a molecular weight cutoff of 3000 to 10000; and NTR7410 and NTR7450 from Nitto Denko Corporation.

[0039] Next, the pH of the decomposition solution obtained is adjusted to be acidic. By adjusting the pH of the decomposition solution to be acidic, a part or all of the active ingredient of the appetite stimulant of the present invention is precipitated as a solid content.

[0040] The method of adjusting the pH of the decomposition treatment liquid to be acidic is, for example, a method of adding an acidic solution to the decomposition treatment liquid. From the viewpoint of application in the food industry field, hydrochloric acid is preferably used as the acidic solution. The concentration of hydrochloric acid may be appropriately set within a range in which the pH can be adjusted, for example, 0.1 to 35 mass%.

[0041] The pH of the decomposition treatment liquid after pH adjustment (hereinafter also referred to as "acid treatment liquid") is preferably 4.5 or less, more preferably 4.0 or less, and even more preferably 3.5 or less, from the viewpoint of easily obtaining components that increase the appetite of abalone or sea urchin. From the same viewpoint, the pH of the acid treatment liquid is preferably 1.5 or more, more preferably 2.0 or more, and even more preferably 2.5 or more.

[0042] The acidic solution is then filtered. The filtration separates the solid matter precipitated in the acidic solution from the liquid matter other than the solid matter, and the solid matter (residue) can be obtained. This solid matter can be used as an extract derived from bagasse, which has the effect of increasing the appetite of abalone or sea urchin.

[0043] The filtration of the acidic treatment liquid may be performed by natural filtration, reduced pressure filtration, pressure filtration, centrifugal filtration, etc., and is preferably performed by pressure filtration. Pressure filtration may be performed using a pressure filter (filter press). The filtration conditions can be appropriately adjusted within a range in which the solid matter precipitated in the acidic treatment liquid can be captured.

[0044] Diatomaceous earth may be added to the acidic treatment liquid before filtration. By adding diatomaceous earth, the components (solids) having the effect of increasing the appetite of abalone or sea urchin are captured in the pores of the porous diatomaceous earth, making it easier to obtain an extract derived from bagasse. In this case, the extract derived from bagasse may be the solid matter itself after filtration. In other words, the extract derived from bagasse may contain the components derived from bagasse by the above-mentioned treatment and diatomaceous earth.

[0045] The type or place of origin of the diatomaceous earth that can be used is not particularly limited, and diatomaceous earth produced in various places can be used as appropriate. Calcined products can also be used as the diatomaceous earth. The shape of the diatomaceous earth is preferably powder or granular.

[0046] The physical properties or grade of the diatomaceous earth can be appropriately selected. For example, the 50% average particle size (D50, measured by a laser method) is 10 to 80 μm, the transmittance based on the Darcy formula is 0.01 to 10 darcy, and the bulk density (cake bulk density) is 0.15 to 0.3 g / cm. 3 The diatomaceous earth may be a commercially available product.

[0047] The amount of diatomaceous earth added may be 0.2 mass% or more, 0.5 mass% or more, or 0.8 mass% or more, and may be 2 mass% or less, 1.6 mass% or less, or 1.3 mass% or less, based on the total amount of the acidic treatment liquid and the diatomaceous earth.

[0048] The bagasse extract obtained by the above method may be subjected to a drying treatment such as natural drying or hot air drying, if necessary.

[0049] The appetite enhancer may consist only of the active ingredient, an extract derived from bagasse, or may contain other ingredients that can be used as feed for abalone or sea urchins, such as carbohydrates such as wheat flour, seaweeds such as sea lettuce, wakame seaweed, kombu seaweed, and green laver, fish-derived ingredients such as fish meal and fish oil, various vitamins, minerals such as calcium and phosphorus, and thickeners such as sodium alginate.

[0050] When the appetite stimulant contains other ingredients, the content of bagasse extract may be 0.005% by mass or more, 0.007% by mass or more, or 0.01% by mass or more, and may be 0.5% by mass or less, 0.1% by mass or less, or 0.05% by mass or less, based on the total amount of the appetite stimulant.

[0051] The shape of the appetite enhancer is not limited as long as it is a shape that can be ingested by the abalone or sea urchin. The appetite enhancer may be in the form of a solid (powder, granules, etc.), liquid (solution, suspension, etc.), paste, gel, etc. Alternatively, the appetite enhancer may be formed into a bead-shaped gel bait by gelling a liquid or paste.

[0052] The appetite enhancer can be fed to the abalone or sea urchin (oral administration). The amount of intake may be an amount that provides 0.1 μg / g (body weight) or more, 0.5 μg / g (body weight) or more, or 1 μg / g (body weight) or more of the bagasse extract per day, and may be an amount that provides 50 μg / g (body weight) or less, 10 μg / g (body weight) or less, or 5 μg / g (body weight) or less. Ingestion of this amount can sufficiently stimulate the appetite of the abalone or sea urchin.

[0053] Since the appetite enhancer for abalone or sea urchin according to this embodiment can enhance the appetite of abalone or sea urchin, it can be used for promoting their growth, promoting the discharge of toxins accumulated in their bodies, increasing valuable substances in the body to increase nutritional value, improving meat quality, taste quality or flavor, brightening the appearance, activating activity, promoting reproduction, guiding the structure or strength of the shell or spine to make it easier for humans to handle, promoting regeneration to recover from damage caused by feeding, etc. Regarding the use of growth promotion, in marine organisms other than abalone and sea urchin (fish, crustaceans, etc.), the growth of the marine organisms is promoted by increasing the amount of synthesis of insulin-like growth factor I (IGF-I) present in the liver, but this is unrelated to the appetite-enhancing effect of the present invention.

[0054] According to one embodiment, an appetite stimulant for abalone or sea urchin containing an extract derived from bagasse as an active ingredient can be obtained by the above-mentioned production method. That is, the production method for an appetite stimulant for abalone or sea urchin according to one embodiment includes a step of decomposing bagasse by at least one treatment selected from the group consisting of alkali treatment, hydrothermal treatment, acid treatment, and subcritical water treatment to obtain a decomposition treatment liquid, adjusting the pH of the decomposition treatment liquid to an acidic value, and filtering the liquid to obtain a solid. Specific aspects of each step are as described above.

[0055] Next, a neuropeptide Y synthesis promoter in abalone or sea urchin according to one embodiment will be described. A specific aspect of the neuropeptide Y synthesis promoter in abalone or sea urchin may be the same as the appetite stimulant for abalone or sea urchin described above. That is, the neuropeptide Y synthesis promoter in abalone or sea urchin according to one embodiment may be obtained by replacing "appetite stimulant for abalone or sea urchin" in the above description with "neuropeptide Y synthesis promoter in abalone or sea urchin". The same applies to a method for producing the neuropeptide Y synthesis promoter in abalone or sea urchin.

[0056] The neuropeptide Y synthesis promoter in abalone or sea urchin can increase the expression level of mRNA for synthesizing neuropeptide Y, which is present in the brain ganglia of abalone and sea urchin. As a result, the synthesis of neuropeptide Y is promoted in abalone or sea urchin. Neuropeptide Y is a peptide neurotransmitter that is mainly involved in regulating appetite. Increasing neuropeptide Y enhances appetite in abalone or sea urchin.

[0057] In addition to the effect of increasing appetite, neuropeptide Y has effects such as regulating digestive tract function, regulating energy consumption, sexual maturation, regeneration, etc. Therefore, according to one embodiment, the neuropeptide Y synthesis promoter in abalone or sea urchin can be used for increasing appetite, regulating digestive tract function, regulating energy consumption, activating reproductive activity, recovering from damage caused by feeding, etc. EXAMPLES

[0058] The present invention will be described in more detail below with reference to examples, although the present invention is not limited to the following examples.

[0059] <Production of bagasse-derived extract> 3.2 kg of bagasse (water content 50% by mass), which is sugarcane pomace, and 20 L of 0.5% (w / w) aqueous sodium hydroxide solution at 90°C were added to a stainless steel stockpot and mixed for 2 hours to carry out a decomposition treatment. The mixture after the decomposition treatment was separated into insoluble components (fiber, etc.) and a liquid fraction, and approximately 20 L of the liquid fraction was obtained. This separation process was repeated twice to obtain 40 L of liquid fraction (decomposition treatment liquid).

[0060] 475 mL of 35% (w / w) hydrochloric acid was added to the total amount of this decomposition treatment liquid to adjust the pH to 3.0. This was used as the acid treatment liquid. 395 g of diatomaceous earth (an amount equivalent to 1% by mass based on the total amount of the acid treatment liquid and diatomaceous earth) was added to the acid treatment liquid, and pressure filtration was performed using a filter press. After filtration, solid matter containing diatomaceous earth that did not pass through the filter was collected. This was used as an extract derived from bagasse (bagasse extract).

[0061] <Feeding method> We used young Ezo abalone (weight approximately 5.4g) reared at the Marine Education and Research Center attached to the Kitasato University School of Marine Life Sciences. Four plastic cages (30 x 40 x 25cm) were placed in a 1-ton aquarium installed indoors, and 50 young abalone were placed in each cage. A gel feed containing the above bagasse extract was prepared as a feed. That is, the above bagasse extract was mixed with wheat flour (55% by mass), seaweed powder (30% by mass), and crude sodium alginate extract (5% by mass) prepared from wakame stems in an amount such that the final amount added to the gel feed was 0.01% by mass or 0.05% by mass. The mixture was dropped into a calcium chloride solution to gel it. This gel feed was given to abalone juveniles every two days at an amount of 2% by mass per gram of body weight for six months. As control groups, a group (control group 1) was given the same amount of gel feed prepared without the addition of bagasse extract, and a group (control group 2) was given the same amount of commercially available compound feed for abalone juveniles (4N, Nosan Corporation) were prepared. The above test was also conducted on young Ezo abalone weighing approximately 3.2g. However, the feeding period was 5 months, and there was no control group 2. Table 1 shows the outline of the test groups.

[0062] [Table 1]

[0063] <Evaluation of neuropeptide Y expression level> After the feeding period, abalone brain ganglia were collected (n=10) and stored in RNA later solution at 4℃ until use. RNA was extracted from the brain ganglia using RNeasy Mini Kit (QIAGEN). Buffer RLT (500μL) was added to a 1.5mL tube containing approximately 10mg of brain ganglia, and one zirconia bead (Φ3mm) was placed in it. The contents in the tube were disrupted by a cell disrupter (Micro Smash MS-100, Tommy Seiko Co., Ltd.) at 3000rpm for 10 seconds until no solid matter remained. After centrifugation (16700×g, 3 minutes, 24℃), the supernatant was transferred to a new 1.5mL tube. The same amount of 70% ethanol as the supernatant (500μL) was added and mixed by pipetting. The mixture was added to an RNeasy Spin Column and centrifuged (7900×g, 15 seconds, 24°C). Then, Buffer RW1 (700 μL) was added to the column, and after centrifugation, Buffer RPE (500 μL) was added to the column and centrifuged again. The same amount of Buffer RPE was added again and centrifuged (7900×g, 2 minutes, 24°C) to wash the column. The column was set in a new 1.5 mL tube and RNeasy Free Water (20 μL) was added to the center of the column. After standing for 1 minute, total RNA was eluted by centrifugation (7900×g, 1 minute, 24°C). The concentration of the obtained total RNA was calculated by measuring the absorbance at 260 nm and 280 nm using an absorbance meter (NanoVue Plus, GE Healthcare), and was stored at -80°C until use.

[0064] β-actin (βAN) was used as an internal standard. Primers for abalone neuropeptide Y (NPY) and βAN were designed based on the cDNA sequences using Primer3 web version 0.4.0 (http: / / bioinfo.ut.ee / primer3-0.4.0 / ) software. KAPA SYBER FAST One Step qRT-PCR Kit was used for semi-quantitative PCR of NPY. Total RNA prepared from brain ganglia (n=4) as a standard sample was serially diluted to 0.0098, 0.0391, 0.1563, 0.625, 2.5 and 10ng. The serially diluted total RNA (2μL) was added to the wells of a plate (96well Hi-Plate for Real Time, Takara Bio Inc.), followed by the addition of 5.0μL of KAPA SYBER FAST qPCR Master Mix, 0.2μL of dUTP, 0.2μL of KAPA RT Mix, 2.2μL of sterile water, 0.2μL of forward primer and reverse primer. The concentrations of the NPY and βAN primers were 5.0 and 10μM, respectively. The PCR reaction consisted of a reverse transcription reaction at 42°C for 5 minutes, followed by an enzyme activation reaction at 95°C for 10 minutes, followed by 40 cycles of thermal denaturation (95°C, 5 seconds) and annealing / extension reaction (60°C, 30 seconds). The thermal real-time PCR device used was the Thermal Cycler Dice Real Time System (Takara Bio Inc.).

[0065] Figure 1(a) shows the expression level of NPY mRNA in the brain ganglia of each test group, taken from juvenile Ezo abalone weighing 5.4g, 6 months after the start of the test. Figure 1(b) shows the expression level of NPY mRNA in the brain ganglia of each test group, taken from juvenile Ezo abalone weighing 3.2g, 6 months after the start of the test. In both cases, the expression level of NPY mRNA in the brain ganglia of administration groups 1 and 2, which consumed gel feed containing bagasse extract, was significantly higher than that of control group 1 (administration group 1: p<0.05, administration group 2: p<0.01). Therefore, it was found that bagasse extract enhances the expression level of NPY, which regulates the appetite of abalone.

Claims

1. The method for producing an appetite stimulant for abalone or sea urchin includes a step of decomposing bagasse by at least one treatment selected from the group consisting of an alkali treatment, a hydrothermal treatment, an acid treatment, and a subcritical water treatment to obtain a decomposition treatment liquid, adjusting the pH of the decomposition treatment liquid to an acidic value, and then filtering the liquid to obtain a solid matter.

2. The method of claim 1 , wherein diatomaceous earth is added to the decomposition solution prior to the filtration.

3. A method for producing a promoter for the synthesis of neuropeptide Y in abalone or sea urchin, comprising the steps of: decomposing bagasse by at least one treatment selected from the group consisting of alkali treatment, hydrothermal treatment, acid treatment, and subcritical water treatment to obtain a decomposition treatment liquid; adjusting the pH of the decomposition treatment liquid to an acidic value; and filtering the decomposition treatment liquid to obtain a solid matter.

4. The method of claim 3 , wherein diatomaceous earth is added to the decomposition solution prior to the filtration.

Images