Natural astaxanthin conditioner capable of promoting growth and resisting diseases and preparation method of natural astaxanthin conditioner

Abstract

The invention belongs to the technical field of aquaculture, and provides a growth-promoting disease-resistant natural astaxanthin conditioner and a preparation method thereof. According to the growth-promoting and disease-resisting natural astaxanthin conditioner provided by the invention, the fermented astaxanthin is combined with the seaweed active extract and the deep sea fish oil for preparation, and is compounded with the compound probiotic agent, the natural mineral salt and the like, so that the efficacy can be greatly improved, the synergistic and complementary effects of all the components in the aspects of activity and bioavailability are fully exerted, and the conditioner is easier to absorb and free of side effects; the feed can accelerate nutrient absorption of fish bodies, promote color development, enhance immunity of the fish bodies, prevent diseases and remove bacteria, and is helpful for healthy and rapid growth of aquarium fish.

Description

Technical Field

[0001] The invention belongs to the technical field of aquaculture, and particularly relates to a growth-promoting and disease-resistant natural astaxanthin conditioning agent and a preparation method thereof. Background Art

[0002] During the breeding process of ornamental fish, the use of feed and medicines leads to poor health of fish, slow growth and development, weak constitution, and susceptibility to diseases, which in turn increases breeding costs and investment risks. In aquaculture, astaxanthin is also often used as a natural antioxidant to reduce oxidative stress during aquaculture, enhance immunity and disease resistance of aquaculture, promote growth and development, and increase yield and quality.

[0003] Astaxanthin is a powerful natural antioxidant that reduces the damage of oxidative stress to organisms. It has extremely strong biological activity and can significantly enhance the immunity of fish, improve the fish's resistance to disease, and reduce the use of antibiotics. In addition, astaxanthin can also promote the growth of fish, improve feed conversion rate, and shorten the breeding cycle.

[0004] Astaxanthin, seaweed active extracts, compound probiotics and natural mineral salts are compounded into ornamental fish conditioners. The synergistic effect of various components greatly improves the protection and regulation of fish bodies, which not only improves the reproductive capacity of fish, but also improves the body color and appearance, making the fish's appearance present bright colors. At the same time, it can reduce fish deformities and prevent diseases. During the breeding process, ornamental fish often face pressures such as water quality changes and disease threats. The conditioner can also enhance the fish's ability to resist stress, help them maintain a healthy physiological state, and thus increase the survival rate and overall yield of larvae, which not only improves breeding efficiency, but also increases the economic benefits of farmers. Summary of the invention

[0005] The purpose of the present invention is to provide a growth-promoting and disease-resistant natural astaxanthin conditioning agent to address the problems of slow growth, low resistance, high deformity rate, etc. in the existing ornamental fish breeding process. The conditioning agent can effectively enhance the immunity of fish, promote growth and reproduction, and improve breeding efficiency and product quality.

[0006] The growth-promoting and disease-resistant natural astaxanthin conditioning agent provided by the present invention comprises, by weight:

[0007] Astaxanthin fermentation liquid 70-80, enzymatic seaweed extract 15-25, deep sea fish oil 1-2, compound probiotics 3-4, compound vitamins 2-3, natural mineral salt 5-10, allicin 0.05-0.1.

[0008] Preferably, the astaxanthin fermentation broth is a fermentation broth produced when Yarrowia lipolytica ferments glucose as a substrate to produce L-astaxanthin, and the astaxanthin content in the fermentation broth is ≥700 mg / L.

[0009] Preferably, the enzymatically hydrolyzed seaweed active extract is obtained in the following process: the seaweed is micronized and then enzymatically extracted by cellulase, pectinase and brown algae lyase, and an extract is produced in the process, and the seaweed oligosaccharide content of the extract is ≥3.5wt%.

[0010] The enzymatically hydrolyzed seaweed active extract is an extract rich in seaweed oligosaccharides obtained by enzymatic hydrolysis of brown algae lyase after being acted on by cellulase and pectinase under alkaline conditions. The biggest feature of the active extract is that it is a small molecule substance and is more easily absorbed by fish, and its seaweed oligosaccharide content is ≥3.5wt%.

[0011] Preferably, the natural mineral salt is selected from any two or more of methylene blue salt, white mineral salt, yellow pink salt, and multidimensional mineral salt.

[0012] Preferably, the composite probiotic is selected from any three or more of Lactobacillus plantarum, Coccus, photosynthetic bacteria, Bacillus, Acetobacter, and Actinomycetes.

[0013] The fermentation preparation process of the growth-promoting and disease-resistant natural astaxanthin conditioning agent provided by the present invention comprises the following steps:

[0014] Yarrowia lipolytica was fermented with glucose as substrate under the conditions of aeration ratio of 1.5-3.0, fermentation temperature of 28±2°C, pH of 5.5-6.8, and stirring speed of 300-600rpm. In the early stage of fermentation, when the biomass / OD600 was lower than 11.81, the glucose concentration was controlled at 1.5-1.8 g / L by feedback feeding.

[0015] When the astaxanthin / OD475 value reached 8.53, corn slurry was added until the astaxanthin / OD475 reached 16.08, and then the addition of corn slurry was stopped. The culture was continued until there was no obvious change in astaxanthin content for 72 hours, and the fermentation was stopped to obtain astaxanthin fermentation liquid.

[0016] A growth-promoting and disease-resistant natural astaxanthin conditioning agent is prepared by the following steps:

[0017] (1) mixing 70-80 parts of astaxanthin fermentation liquid, 15-25 parts of enzymatic hydrolyzed seaweed active extract, and 1-2 parts of deep-sea fish oil to obtain a mixture with a uniform liquid phase;

[0018] (2) The mixture obtained in (1) is spray-dried into a powder, and then mixed with 3-4 parts of a composite probiotic, 2-3 parts of a composite vitamin, 5-10 parts of natural mineral salt, and 0.05-0.1 parts of allicin in a powder mixer to obtain a conditioning agent.

[0019] Preferably, the mixing process in (1) is carried out in a high-pressure homogenizer under high pressure, strong shear force and high-frequency oscillation to perform micronization and homogenization, and finally obtain a liquid phase uniform mixture, wherein the pressure during high-pressure homogenization is 300-700 bar.

[0020] Preferably, the spray drying process in (2) is carried out in a drying tower, the air inlet temperature of the drying tower is 120-150°C, and the air outlet temperature of the drying tower is 70-90°C.

[0021] In addition, the application of the growth-promoting and disease-resistant natural astaxanthin conditioning agent provided by the present invention in the preparation of growth-promoting and disease-resistant products for ornamental fish is also the key protection content of this patent.

[0022] The advantage of the present invention is that the conditioner of the present invention has a strong feeding effect, promotes nutrient absorption, promotes color development, enhances immunity, reduces fish deformities, and has significant disease prevention and sterilization effects. At the same time, it can also regulate water quality, adjust osmotic pressure, and protect the healthy and rapid growth of ornamental fish.

[0023] Compared with the prior art, the present invention has the following advantages and effects:

[0024] (1) The present invention uses astaxanthin fermentation broth as raw material, which has the advantages of low cost, and the fermentation broth is rich in amino acid nitrogen, mannan, β-glucan and other Yarrowia inactivated biomass, which can effectively adsorb a variety of mycotoxins, anti-oxidation, scavenge free radicals, protect the liver and detoxify, and can also provide high-quality yeast protein, replace the use of animal-source proteins such as fish meal, and reduce the spread of animal-source pathogens. However, relying solely on a single astaxanthin fermentation broth is not enough to alleviate the stress caused by changes in the water environment, increased breeding density, etc., resulting in reduced fish immunity and survival rate. In addition, the use of a single astaxanthin fermentation broth makes the fish have low feeding appeal and poor palatability, which greatly reduces the utilization rate of astaxanthin, resulting in increased breeding costs and reduced benefits;

[0025] (2) The conditioning agent prepared by the present invention contains seaweed active substances such as brown algae oligosaccharides and fucoidan oligosaccharides, which can stimulate the secretion of growth hormone in fish, promote their growth and development, accelerate intestinal digestion and absorption in fish, improve the utilization rate of astaxanthin, make their body color brighter, and at the same time stimulate the immune response of fish, increase the body's stress level, reduce deaths caused by diseases, and improve the survival rate; in addition, the natural mineral salt in the conditioning agent softens the water quality to a certain extent, regulates the water environment, promotes the growth and reproduction of beneficial microorganisms, and inhibits the growth of harmful microorganisms. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in conjunction with specific implementation methods.

[0027] Example 1

[0028] 1.1 Preparation of astaxanthin fermentation broth

[0029] The fermentation medium formula of astaxanthin fermentation broth is as follows ( / L): 9g glucose, 6g protein powder, 8g yeast extract, 3g dipotassium hydrogen phosphate, 3g ammonium sulfate, and 2g magnesium sulfate heptahydrate.

[0030] The fermentation process is as follows: Yarrowia lipolytica is fermented with glucose as a substrate under the conditions of an aeration ratio of 2.5, a fermentation temperature of 30°C, ammonia water controlling pH 6.0, and a stirring speed of 400 rpm. In the early stage of fermentation, when the biomass / OD600 is lower than 11.81, the glucose concentration is controlled at 1.5 g / L by feedback feeding. In the middle and late stages of fermentation, that is, when the astaxanthin / OD475 value reaches 8.53, corn slurry is added until the astaxanthin / OD475 reaches 16.08 and the addition of corn slurry is stopped. The culture is continued until 72 hours and the fermentation is stopped when there is no obvious change in astaxanthin content, to obtain astaxanthin fermentation broth, and the astaxanthin content in the fermentation broth is measured to be 729 mg / L.

[0031] 1.2 Preparation of enzymatic seaweed extract

[0032] Weigh 1000g of kelp, wash, dry and micronize it, add tap water 40 times the weight of the kelp, 8.0g of neutral cellulase, 4g of alkaline pectinase, control the pH to 7.5 with sodium carbonate, stir at 60℃ for 3h, add 5g of brown algae lyase, continue stirring for 1.5h, centrifuge at 4500r / min, the supernatant is the enzymatic seaweed extract, and the seaweed oligosaccharide content is measured to be 3.6wt%.

[0033] 1.3 Preparation of natural astaxanthin conditioning agent for promoting growth and resisting diseases:

[0034] S1: Prepare the raw materials according to the following weights:

[0035] Take 700g of the astaxanthin fermentation liquid in 1.1, 200g of the enzymatic seaweed extract in 1.2, 20g of deep-sea fish oil, 30g of compound probiotics, 30g of compound vitamins, 100g of natural mineral salt, and 0.5g of allicin.

[0036] S2: (1) taking the following raw materials by weight: 700 g of astaxanthin fermentation liquid, 200 g of enzymatic hydrolyzed seaweed extract, and 20 g of deep-sea fish oil, and mixing them. The mixing process is carried out in a high-pressure homogenizer, and micronization and homogenization are carried out under high pressure, strong shear force and high-frequency oscillation to finally obtain a liquid phase uniform mixture, wherein the pressure during high-pressure homogenization is 500 bar, and a liquid phase uniform mixture is obtained;

[0037] (2) The uniform liquid mixture in (1) is subjected to centrifugal spray drying, with the inlet air temperature of the drying tower controlled at 140° C. and the outlet air temperature controlled at 80° C., to prepare dry powdered astaxanthin;

[0038] (3) The dry powdered astaxanthin prepared above was thoroughly mixed with 30 g of multivitamins, 0.5 g of allicin, natural mineral salts (25 g of methylene blue salt, 25 g of white mineral salt, 25 g of yellow pink salt, 25 g of multidimensional mineral salt), and a composite probiotic agent (10 g of plant lactobacillus, 10 g of photosynthetic bacteria, and 10 g of Bacillus) in a powder mixer to obtain a conditioner.

[0039] Example 2

[0040] 2.1 Preparation of astaxanthin fermentation broth

[0041] The fermentation medium formula of astaxanthin fermentation broth is as follows ( / L): 9g glucose, 6g protein powder, 8g yeast extract, 3g dipotassium hydrogen phosphate, 3g ammonium sulfate, and 2g magnesium sulfate heptahydrate.

[0042] The fermentation process is as follows: Yarrowia lipolytica, during the fermentation process, the ventilation ratio is controlled at 2.5, the fermentation temperature is 30°C, the pH value is controlled at 6.0 with ammonia water, the stirring speed is 400rpm, and the concentration of glucose is controlled at 1.7g / L by glucose feedback feeding in the early stage of fermentation. In the middle and late stages of fermentation, appropriate corn slurry is added until there is no obvious change in the astaxanthin content in the fermentation liquid, and the fermentation is stopped. The astaxanthin content in the fermentation liquid is measured to be 743mg / L.

[0043] 2.2 Preparation of enzymatic seaweed extract

[0044] Preparation process of enzymatic seaweed extract: weigh 1000g of kelp, wash, dry, and micronize, add tap water 40 times the weight of the kelp, 6g of neutral cellulase, 3g of alkaline pectinase, control the pH to 7.0 with sodium carbonate, stir at 60℃ for 4h, add 5g of brown algae lyase, continue stirring for 1.5h, centrifuge at 4500r / min, the supernatant is the enzymatic seaweed extract, and the seaweed oligosaccharide content is measured to be 3.5wt%.

[0045] 2.3 Preparation of natural astaxanthin conditioning agent for promoting growth and resisting diseases:

[0046] S1: Prepare the raw materials according to the following weights:

[0047] Take 800g of the astaxanthin fermentation liquid in 2.1, 150g of the enzymatic seaweed extract in 2.2, 10g of deep-sea fish oil, 30g of compound probiotics, 40g of compound vitamins, 100g of natural mineral salt, and 0.5g of allicin.

[0048] S2: (1) taking the following raw materials: 800 g of astaxanthin fermentation broth, 150 g of enzymatic hydrolyzed seaweed extract, and 10 g of deep-sea fish oil, and mixing them. The mixing process is carried out in a high-pressure homogenizer under high pressure, strong shear force and high-frequency oscillation to micronize and homogenize the mixture, and finally a liquid phase homogeneous mixture is obtained. The pressure during high-pressure homogenization is 500 bar, and a liquid phase homogeneous mixture is obtained.

[0049] (2) taking the uniform liquid phase mixture in (1) and using a centrifugal spray dryer, controlling the drying tower air inlet temperature to 140° C. and the air outlet temperature to 80° C., to prepare dry powdered astaxanthin;

[0050] (3) The dry powdered astaxanthin prepared above was thoroughly mixed with 40 g of multivitamins, 0.5 g of allicin, natural mineral salts (25 g of methylene blue salt, 25 g of white mineral salt, 25 g of yellow powder salt, 25 g of multidimensional mineral salt), and a composite probiotic agent (10 g of plant lactobacillus, 10 g of coccobacillus, 10 g of photosynthetic bacteria, and 10 g of Bacillus) in a powder mixer to obtain a conditioning agent.

[0051] Example 3

[0052] 3.1 Preparation of astaxanthin fermentation broth

[0053] The fermentation medium formula of astaxanthin fermentation broth is as follows ( / L): 9g glucose, 6g protein powder, 8g yeast extract, 3g dipotassium hydrogen phosphate, 3g ammonium sulfate, and 2g magnesium sulfate heptahydrate.

[0054] The fermentation process is as follows: Yarrowia lipolytica, during the fermentation process, the ventilation ratio is controlled at 2.5, the fermentation temperature is 30°C, the pH value is controlled at 6.0 with ammonia water, the stirring speed is 400rpm, and the concentration of glucose is controlled at 1.7g / L by glucose feedback feeding in the early stage of fermentation. In the middle and late stages of fermentation, appropriate corn slurry is added until there is no obvious change in the astaxanthin content in the fermentation liquid. The fermentation is stopped and the astaxanthin content in the fermentation liquid is measured to be 982mg / L.

[0055] 3.2 Preparation of enzymatic seaweed extract

[0056] Preparation process of enzymatic seaweed extract: weigh 1000g of kelp, wash, dry, and micronize, add tap water 40 times the weight of the kelp, 8.0g neutral cellulase, 5g alkaline pectinase, control pH7.0 with sodium carbonate, stir at 60℃ for 4.5h, add 7g brown algae lyase, continue stirring for 2h, centrifuge at 4500r / min, the supernatant is the enzymatic seaweed extract, and 3.9wt% of seaweed oligosaccharides are measured.

[0057] 3.3 Preparation of natural astaxanthin conditioning agent for promoting growth and resisting diseases:

[0058] S1: Prepare the raw materials according to the following weights:

[0059] Take 750g of the astaxanthin fermentation liquid in 1.1, 175g of the enzymatic seaweed extract in 1.2, 10g of deep-sea fish oil, 40g of compound probiotics, 30g of compound vitamins, 100g of natural mineral salt, and 0.7g of allicin.

[0060] S2: (1) taking the following raw materials by weight: 750 g of astaxanthin fermentation liquid, 175 g of enzymatic hydrolyzed seaweed extract, and 10 g of deep-sea fish oil, and mixing them. The mixing process is carried out in a high-pressure homogenizer under high pressure, strong shear force and high-frequency oscillation to micronize and homogenize the mixture, and finally a liquid phase homogenous mixture is obtained. The pressure during high-pressure homogenization is 550 bar, and a liquid phase homogenous mixture is obtained.

[0061] (2) The uniform liquid mixture in (1) is subjected to centrifugal spray drying, with the drying tower air inlet temperature controlled at 141° C. and the air outlet temperature controlled at 86° C., to prepare dry powdered astaxanthin;

[0062] (3) The dry powdered astaxanthin prepared above was thoroughly mixed with 30 g of multivitamins, 0.7 g of allicin, natural mineral salts (25 g of methylene blue salt, 25 g of white mineral salt, 25 g of yellow powder salt, 25 g of multidimensional mineral salt), and a composite probiotic agent (10 g of plant lactobacillus, 10 g of coprococcus, 10 g of acetic acid bacteria, and 10 g of actinomycetes) in a powder mixer to obtain a conditioning agent.

[0063] Example 4

[0064] The difference from Example 2 is that:

[0065] The astaxanthin content in the astaxanthin fermentation broth prepared in 4.1 is 1019 mg / L, the seaweed oligosaccharide content in the enzymatic seaweed extract prepared in 4.2 is 3.9 wt %, and the compounding conditions and preparation methods of other substances are the same.

[0066] Example 5

[0067] The difference from Example 2 is that: 5.1 prepares astaxanthin fermentation broth with an astaxanthin content of 1154 mg / L, 5.3 prepares natural mineral salts (33 g of methylene blue salt, 33 g of white mineral salt, 33 g of multidimensional mineral salt) and a compound probiotic agent (10 g of plant lactobacillus, 10 g of coccobacillus, and 10 g of photosynthetic bacteria) in the growth-promoting and disease-resistant natural astaxanthin conditioner, and the compounding conditions and preparation methods of other substances are the same.

[0068] Example 6 Effect Evaluation

[0069] A common commercially available product was used as a comparative example.

[0070] The above-mentioned examples 1, 2, 3, 4, 5 and the comparative example are applied as follows: the experimental group and the control group are both selected to carry out the experiment with healthy red and white koi, and the experimental fish are randomly divided into 6 groups, each group is stocked with 30 fish, and the feeding is continued for 3 months. The control group uses ordinary commercial products, and the experimental group uses the conditioning agent obtained in the above-mentioned examples 1, 2, 3, 4, 5, and the other management conditions are the same. The statistical data and analysis are shown in Table 1:

[0071] Table 1 Effects of different conditioners on growth, body color and immunity of koi

[0072]

[0073] From the above data, it can be seen that after applying natural astaxanthin conditioning agent, the weight gain rate, survival rate, body color and resistance of koi have all improved to varying degrees.

[0074] Weight gain rate: The weight gain rates of experimental groups 4 and 5 were the highest, reaching 129.58% and 127.51% respectively;

[0075] Survival rate: The survival rates of experimental groups 1 to 5 were also slightly higher than those of the control group, and experimental group 4 reached a survival rate of 100%;

[0076] Body color: The brightness, redness, and yellowness values ​​of experimental groups 2 to 5 were generally higher than those of the control group, showing brighter or deeper body colors;

[0077] Resistance: The serum lysozyme enzyme values ​​of experimental groups 1 to 5 were all higher than those of the control group, and the enzyme values ​​of experimental groups 4 and 5 were the highest, which means that these conditioners have a positive effect on improving the immunity of koi.

[0078] The different compounding ratios of the astaxanthin conditioning agent have different effects on koi, indicating that there is a certain synergistic and complementary effect between the substances. Therefore, the conditioning agent has a positive effect on the growth and immunity of koi.

[0079] In summary, the growth-promoting and disease-resistant natural astaxanthin conditioning agent provided by the present invention can not only greatly improve the efficacy, give full play to the synergistic and complementary effects of fermented astaxanthin, seaweed active extracts, and deep-sea fish oil in terms of activity and bioavailability, is easier to absorb, has no side effects, but also can accelerate the absorption of fish nutrients and promote color development, enhance fish immunity, prevent diseases and eliminate bacteria, and help ornamental fish grow healthily and quickly.

[0080] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent changes and modifications made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A natural astaxanthin conditioning agent that promotes growth and resists diseases. It is characterized in that In parts by weight, the conditioning agent contains: Astaxanthin fermentation liquid 70-80, enzymatic seaweed extract 15-25, deep sea fish oil 1-2, compound probiotics 3-4, compound vitamins 2-3, natural mineral salt 5-10, allicin 0.05-0.

1.

2. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 1, It is characterized in that The astaxanthin fermentation liquid is a fermentation liquid produced when Yarrowia lipolytica ferments and produces left-handed astaxanthin using glucose as a substrate, and the astaxanthin content in the fermentation liquid is ≥700 mg / L.

3. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 1, It is characterized in that The enzymatically hydrolyzed seaweed active extract is obtained in the following process: the seaweed is micronized and then enzymatically extracted by cellulase, pectinase and brown algae lyase, and an extract is produced in the process, and the seaweed oligosaccharide content of the extract is ≥3.5wt%.

4. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 1, It is characterized in that The natural mineral salt is selected from any two or more of methylene blue salt, white mineral salt, yellow pink salt and multidimensional mineral salt.

5. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 1, It is characterized in that The composite probiotic agent is selected from any three or more of plant lactobacillus, coprococcus, photosynthetic bacteria, bacillus, acetobacter and actinomycetes.

6. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 2, It is characterized in that The fermentation preparation process comprises the following steps: Yarrowia lipolytica was fermented with glucose as substrate under the conditions of aeration ratio of 1.5-3.0, fermentation temperature of 28±2°C, pH of 5.5-6.8, and stirring speed of 300-600rpm. In the early stage of fermentation, when the biomass / OD600 was lower than 11.81, the glucose concentration was controlled at 1.5-1.8 g / L by feedback feeding. When the astaxanthin / OD475 value reached 8.53, corn slurry was added until the astaxanthin / OD475 reached 16.08, and then the addition of corn slurry was stopped. The culture was continued until there was no significant change in astaxanthin content for 72 hours, and the fermentation was stopped to obtain astaxanthin fermentation liquid.

7. The growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 1 is prepared by the following steps: (1) mixing 70-80 parts of astaxanthin fermentation liquid, 15-25 parts of enzymatically hydrolyzed seaweed active extract, and 1-2 parts of deep-sea fish oil to obtain a uniform liquid mixture; (2) The mixture obtained in (1) is spray-dried into a powder, and then mixed with the composite probiotic, composite vitamins, natural mineral salt, and allicin in a powder mixer to obtain a conditioning agent.

8. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 7, It is characterized in that The mixing process in (1) is to perform micronization and homogenization in a high-pressure homogenizer under the action of high pressure, strong shear force and high-frequency oscillation, and finally obtain a liquid phase uniform mixture, wherein the pressure during high-pressure homogenization is 300-700 bar.

9. A growth-promoting and disease-resistant natural astaxanthin conditioning agent as claimed in claim 7, It is characterized in that During the spray drying in (2), the air inlet temperature is 120-150°C, and the air outlet temperature of the drying tower is 70-90°C.

10. Use of the astaxanthin conditioning agent according to claim 1 in the preparation of ornamental fish growth-promoting and disease-resistant products.

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