EP2410860A1

EP2410860A1 - Use of hydrogen peroxide compositions in aquatic environments

Info

Publication number: EP2410860A1
Application number: EP10718090A
Authority: EP
Inventors: Philip Adolf Van Geetruy
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-03-27
Filing date: 2010-03-03
Publication date: 2012-02-01

Abstract

The invention relates to a composition, whereby the weight ratio of hydrogen peroxide to sorbitol is comprised between 5:1 and 7:1.The invention further relates to the use of a composition comprising hydrogen peroxide and sorbitol in an aqueous medium comprising an aquatic animal and/or aquatic plant.

Description

Use of hydrogen peroxide compositions in aquatic environments

Field of the invention

The present invention relates to the use of compositions comprising hydrogen peroxide and sorbitol in aquatic environments, in particular to the use of these compositions in aquaria and aquaculture. The invention further relates to a method for controlling an infection in an aqueous medium, comprising supplying hydrogen peroxide and sorbitol to an aqueous medium comprising an aquatic organism. The invention also relates to compositions comprising hydrogen peroxide and sorbitol.

Background of the invention Chemicals suitable for use in aquatic environments have been sought for many years. Especially in aquaculture, e.g. in fish hatcheries, fish farms and aquaria, chemicals should be effective, e.g. for desinfection, but harmless to aquatic plants and/or animals.

Dosing a chemical to an aquatic environment housing aquatic plants and/or animals is particularly tricky. On one hand the chemical should be dosed in an amount sufficient, for instance for the treatment of algal fouling or for controlling microbial or bacterial infections. On the other hand, an aquatic plant and/or animal is present which is particularly sensitive to the presence of chemicals. It is known that animals with mucous membranes such as fish or frogs, are particularly responsive to changes in their habitat. A shift in water pH, temperature, oxygen content may cause animal deaths.

Exposure of aquatic plants and/or animals to chemicals such as desinfectants causes stress, particularly when the plant and/or animal are in a diseased state. Desinfectants such as chlorine based or formaline based products have been replaced by products with an improved toxicity profile, such as hydrogen peroxide.

Upon dilution with water hydrogen peroxide (H2O2) degrades to water and oxygen. This is advantageous as these degradation products are less harmful then for instance chloramine generated by clorine based products, Degradation of hydrogen peroxide is influenced by factors such as temperature, light, water composition, presence of fish waste, etc. This makes it very difficult and tedious to determine what dose of hydrogen peroxide should be supplied. Overdosing may cause plant and animal deaths. In fish farms this may have a large economical impact.

There remains a need in the art, for compositions comprising hydrogen peroxide which are safe in use, effective, less toxic, easy to dose, stable and economically affordable.

It is an object of the present invention to provide a solution to at least one of the above mentioned problems.

Summary of the invention

The invention thereto provides uses of a composition comprising hydrogen peroxide and sorbitol in an aqueous medium comprising an aquatic plant and/or animal.

It was surprisingly found that sorbitol provides a cell and organism protective function to organisms sensitive to hydrogen peroxide, such as an aquatic plant and/or animal. The inventors have observed that the effect provided by the use of sorbitol in combination with hydrogen peroxide, is present even in very dilute conditions as encountered in ponds and aquaria.

Sorbitol is known as a stimulant to plant growth. Based on this knowledge it was believed that sorbitol would accelerate the degradation of hydrogen peroxide in the presence of aquatic plants and/or animals feeding on sorbitol. The inventors found to their surpirse that hydrogen peroxide in the presence of sorbitol remained effective, e.g. for use as desinfectant.

In a preferred embodiment, said aquatic plant is a sea weed. In a preferred embodiment, said aquatic animal is an aquatic mammal, an aquatic bird, a fish, an aquatic reptile, an amphibian, and an aquatic invertebrate. Use in an aquatic environment with fish was found to be particularly beneficial. The invention can be used in the presence of aquatic animals and/or plants of varying sensitivity to hydrogen peroxide. In a preferred embodiment of the above described use, said composition has a weight ratio of hydrogen peroxide to sorbitol comprised between 1 :1 and 10:1. It was found a composition with this ratio was particularly suitable for highly diluted applications the presence of materials and circumstances that otherwise would accelerate hydrogen peroxide breakdown, such as plants, waste, light, temperature, pH.

In a further aspect, the invention relates to the use of a composition comprising hydrogen peroxide and sorbitol for the control of an infection in an aquarium, wherein the composition is added directly to water in the aquarium without first removing aquatic animals or plants from the aquarium. It was found that a use as algae killer of a composition comprising hydrogen peroxide and sorbitol did not require that aquatic animals, such as fish, and/or plants, such as sea weed, should first be removed.

In a further aspect a use according to the invention of a composition comprising hydrogen peroxide and sorbitol is for controlling algae growth in aquaria.

In a further aspect, a use according to the invention of a composition comprising hydrogen peroxide and sorbitol is for controlling parasites on fish.

In a further aspect, a use according to the invention of a composition comprising hydrogen peroxide and sorbitol is for hatching Artemia cysts. Use of sorbitol in combination with hydrogen peroxide was safer than a use of hydrogen peroxide alone.

The invention further relates to a method for controlling an infection in an aquatic environment, comprising the steps of: a) placing an aquatic animal or plant in a water b) supplying the water with hydrogen peroxide or a hydrogen peroxide- producing substance and sorbitol.

In a preferred embodiment of the method, the ratio of hydrogen peroxide to sorbitol in the water is comprised between 1 :1 and 10:1. It was found that this range of hydrogen peroxide to water was best suited for controlling an infection in an aquatic environment. In a preferred embodiment of the method, said aquatic animal is a fish. The method of the invention can be used in aquaculture. The method is very versatile and provides comparable or increased safety to the use of hydrogen peroxide for controlling infections, particularly on or in the presence of fish.

In a preferred embodiment of the method, said infection is a microbial infection and/or a bacterial infection and/or an infection with algae. It was found that a combination of hydrogen peroxide and sorbitol can be used for veterinary purposes, for instance for the treatment of catfish, finnfish and salmonids, against a range of infections.

In a preferred embodiment of the method, said water has an infection with algae. It was found that with a method of the invention aquatic environments such as aquaria can be freed from algae, without being substantially toxic to the carrier of the algae, e.g. plants or fish. The aquatic environment with fish is less sensitive to over dosing compared to a use of hydrogen peroxide alone.

In another aspect of the invention, a composition is provided whereby the weight ratio of hydrogen peroxide to sorbitol is comprised between 5:1 and 7:1. The compositions of the invention provide a protective function. They are effective and are economically affordable.

In a preferred embodiment a composition as described above, whereby the weight ratio of hydrogen peroxide and sorbitol is about 6.7. The compositions of the invention were found to be safe for the environment. Hydrogen peroxide and sorbitol are not persistant in water.

In a preferred embodiment the sorbitol in a composition as described above is D-sorbitol. D-sorbitol was found to provide the highest purity to a composition destined for use in an aquatic environment.

In a further aspect, the invention relates to the use of a composition as described above for use as in one of the applications as previously described. Detailed description of the invention

The present invention provides the use of a composition comprising hydrogen peroxide and sorbitol in an aqueous medium comprising an aquatic animal and/or aquatic plant.

The term "aqueous medium" as used herein refers to marine or freshwater. The term marine refers to any environment relating to the oceans or sears wherein the water is saline. The term freshwater refers to, but is not limited to, lakes, ponds rivers, streams, brooks or any other low salinity water.

The aqueous medium can be contained in a tank, aquarium, ponds or stream. In a preferred embodiment, said aqueous medium is comprised in an aquarium.

In a preferred embodiment of the invention, said aquatic animal is an aquatic mammal, an aquatic bird, a fish, an aquatic reptile, an amphibian, and an aquatic invertebrate.

The term "aquatic animal" as used herein refers to any animal that spends all or some of its life in marine or fesh water. An "aquatic animal" can be, but is not limited to, a mammal such as a seal, sea lion,, walrus, manatee, dugong, porpoise, dolphin, whale, otter, or beaver: a bird such as, but not limited to, a web-footed bird such as a duck, goose, swan, gull, cormorant, penguin, a wading bird such as a coot, moor hen, flamingo, stork, heron; an aquatic reptile such as, but not limited to, an alligator, cayman, crocodile, turtle, snake or lizard, an amphibian such as, but not limited to, frogs, toads, newts and salamanders, neotenous larva or larvae thereof; fish and aquatic invertebrates such as, but not limited to, artemia, Crustacea, insects, or molluscs.

The term "fish" as used herein refers to any marine or freshwater fish species maintained in a tank, aquarium, pool, pond, aquaculture facility, fish farm, or any means other than the natural environment of the fish species. The term "fish" also refers to species and individuals thereof captured, rescued or taken from their native habitat and which may require treatment for microbial infestations. Fish species to which the methods of the present invention may be applied include, but are not limited to, ornamental fish, goldfish, koi, oscar, cichilids, tropical fish and fish for human or animal food such as, but not limited to, finfish, catfish, and salmonids such as trout, or salmon.

The composition employed in the present invention comprises hydrogen peroxide and sorbitol.

The required amount of hydrogen peroxide can be introduced in a composition by adding hydrogen peroxide and/or at least one compound which produces hydrogen peroxide. Hydrogen peroxide producing compounds can be compounds containing peroxide links such as peroxides, perborates, persulfates and peracetates. In a preferred embodiment, a peroxide is selected from magnesium peroxide, calcium peroxide or a combination thereof. These compounds are available in the form of solid products, containing usually between 50% and 70% by weight of the active product. Compared to other solid products magnesium and calcium peroxide have the further advantage of being more stable than for example perborates or persulfates (of potassium or sodium) so that, even when a composition is stored at relatively high temperatures during practically applied periods of time, the capacity of such included magnesium and calcium compounds to produce the required amount of hydrogen peroxide when add to an aqueous medium does not substantially decrease nor will there be a substantial, release of oxygen gas that otherwise would compromise the shelf live of a composition prior to use.

"Sorbitol" as used herein refers to sorbitol, E420, D-sorbitol, also known as D-glucitol. In a preferred embodiment sorbitol is D-sorbitol.

Preferably, the sorbitol used to make up the composition of the invention has a purity of at least 98%, at least 98.5%. The make up of solutions comprising hydrogen peroxide and sorbitol with high purity sorbitol provides very stable solutions. They can be stored safely, without significant degradation of the hydrogen peroxide, for a prolonged period of time, typically for at least 100 days or even for between one and two years. Consequently the composition has a stable, practically non fluctuating amount of hydrogen peroxide. The use of such a composition is more reliable for the dosing of a disinfectant to a fish tank, for instance. In a preferred embodiment the weight ratio of hydrogen peroxide to sorbitol is comprised between 5:1 and 7:1. In a particularly preferred embodiment, the weight ratio of hydrogen peroxide to sorbitol is about 6.7. This ratio provides stability to a composition comprising hydrogen peroxide in a concentration between 50 and 1 % by weight. Upon further dilution of such a composition in a large volume of water, e.g. from an aquarium or a pond, typically presenting a further dilution factor of 1 -10 ml of water into 100 I water, the sorbitol provides a protective function to aquatic plants and/or animals. Aquatic plants and/or animals are less effected to the addition of hydrogen peroxide and sorbitol compared to an addition of hydrogen peroxide.

In a preferred embodiment, said composition further comprises at least one organic acid. It was found that the use of an acid provided neutralization of compounds such as ammonia or nitrogen-containing wastes in an aquatic environment.

The organic acid is preferably present in deficiency in the hydrogen peroxide solution. The weight ratio of hydrogen peroxide to organic acid(s) in a composition of the invention is preferably between 2:1 and 50:1 , more preferably between 5:1 and 20:1.

The organic acid can for instance be citric acid, lactic acid, pentanoic acid, hexanoic acid or glycol acid.

An organic acid is particularly important if the use is in an environment above room temperature, for instance for use in warm water containing tropical fish. The addition of an organic acid acts as a fungicide.

In a preferred embodiment the weight ratio of sorbitol and the organic acid(s) lies between 10:1 and 1 :10, more preferably between 5:1 and 1 :5 or between 1 :2 and 2:1.

A composition comprising hydrogen peroxide and sorbitol can be in a form of a liquid, powder, granules or tablets. In a preferred embodiment the composition is in the form of a liquid. A composition in the form of a liquid can be easily metered in and dosed to an aquatic medium housing an aquatic animal. Such a composition is advantageous for applications requiring that a target amount of hydrogen peroxide be maintained over a fixed period of time. In a preferred embodiment, a composition comprising hydrogen peroxide and sorbitol is used for controlling an infection in an aqueous environment. Aquatic animals and/or plants need not be removed prior to the addition of the composition. This is advantageous as such a use requires less work. For instance, in a use as algae killer, it may not be required to remove fish from an aquarium prior to addition of the composition to the aquarium for removal of algae from a carrier, such as a filter or plant.

In a further aspect a use according to the invention of a composition comprising hydrogen peroxide and sorbitol is for controlling algae growth in aquaria. Use of hydrogen peroxide alone for the treatment of algae can damage water plants and fish particularly sensitive to hydrogen peroxide, such as walleye Sander vitreus, northern pike Esox lucius or paddlefish Polyodon spathula. A use according to the invention was found to be safe. Compared to the use of other algicides, hydrogen peroxide provides aeration to an aquatic environment. The areation, or release of oxygen, was found not to affect sorbitol.

In a preferred embodiment a composition comprising hydrogen peroxide and sorbitol is used as an aquaculture drug.

In a preferred embodiment, a composition comprising hydrogen peroxide and sorbitol is used in the treatment against a disease-causing organism such as, but not limited to, a parasite, bacteria, fungi.

In a further aspect, a use according to the invention of a composition comprising hydrogen peroxide and sorbitol is for controlling parasites. The use can be directed to different life-stages of an aquatic animal, such as to eggs, cysts or adult.

In a preferred embodiment a composition of the invention is used for the treatment of a) freshwater-reared finfish eggs infected with saprolegniasis, a common water mold; or b) freshwater-reared salmonids against bacterial gill disease (Flavobacteήum branchiophilum), or c) freshwater-reared coolwater finfish and channel catfish against external columnaris disease (Flavobacterium columnare), or d) salmon louse (Lepeophtheirus Salmonis)

In a further aspect, a use according to the invention of a composition comprising hydrogen peroxide and sorbitol is for hatching Artemia cysts. Use of hydrogen peroxide for increasing the hatching percentage of Artemia cysts is well-known. For instance, cysts of Artemia are prehydrated in tap water for a period of 30 to 80 minutes and are subsequently treated in a hydrogen peroxide solution diluted with deionized water to concentrations of 1 , 5, 10, 20 or 27 wt%. After treatment times of 1 , 5, 10, 20 or 30 minutes, the cysts are collected on a sieve, rinsed thoroughly with tap water in order to remove traces of H2O2, and incubated in seawater under hatching conditions. A re- incubation of cysts in seawater after removal of the hydrogen peroxide is essential as the applied level of hydrogen peroxide is generally recognised as lethal for animal cells. The inventors have observed that the replacement of a conventional composition comprising hydrogen peroxide with a composition of the invention provides can increase the hatching percentage of Artemia cysts. Use of sorbitol in combination with hydrogen peroxide was safer than a use of hydrogen peroxide alone. In a preferred embodiment a composition with a weight ratio of hydrogen peroxide to sorbitol of between 1 :1 and 10:1 is used. Use of such a composition is advantageous in applications were reliable dosing of a chemical is required, particularly in applications were incorrect dosing can have detrimental effects.

A composition for use in the invention is commercially available, e.g. under the trademark Bioprox, from Verfimport N.V., Belgium. This composition comprising around 50% active ingredients, that is hydrogen peroxide and sorbitol.

In a preferred embodiment a composition is used comprising in addition to hydrogen peroxide and sorbitol also at least one organic acid. The use of this composition provides further fungicidal effect. In a further aspect, the invention provides a method for controlling an infection in an aquatic environment. It consists of placing an aquatic animal in water and supplying the water with hydrogen peroxide or a hydrogen peroxide-producing substance and sorbitol.

In a preferred embodiment the method comprises the immersion (bath treatment) of an aquatic organism, e.g. from an aquaculture, in a composition comprising hydrogen peroxide and sorbitol.

The method of the invention can also be directed to the treatment of a plant in an aquatic environment comprising an aquatic animal. It was found not to be necessary to remove the aquatic animals for the treatment of an aquatic plant. For instance, in the treatment of an aquarium against infestations by algae, it was not required to remove the fish prior to the addition of a composition comprising hydrogen peroxide and sorbitol.

The method is applicable to a large range of aquatic animals such as, but not limited to an aquatic mammal, an aquatic bird, a fish, an aquatic reptile, an amphibian, and an aquatic invertebrate. In a preferred embodiment the method is applied on fish, e.g. in aquaculture. Large scale application of an improved method can result in economical benefits.

In a preferred embodiment the method is for the control of an infection in an aquatic environment. The infection can be caused by a microbe, bacterium or by algae.

The invention will be more readily understood by reference to the following examples, which are included merely for purposes of illustration of certain aspects and embodiments of the present invention and are not intended to limit the invention. Example 1 : preparation of a composition

Table 1 : examples of compositions according to the invention

Example 2: use as an algicide

A composition of around 60 ml of the 3% wt solution of example 1 is added to a tank filled with 250 I water infected with algae. The composition is added over a period of 5 minutes. A clump of algae is killed. Plants are not effected.

Example 3: control of aquatic parasites

Control of salmon lice with hydrogen peroxide and sorbitol of different concentrations is carried out in a fish breeding facility according to the following description. The water temperature is between 6° and 14 ⁰C. Tests 1-9 are performed in small string bags

(3x3x3 m) containing 100 salmon weighing 1-2 kg. The string bag is positioned so as to form a salmon holding bag, to which a 35 wt% hydrogen peroxide and sorbitol solution is supplied. The solution is supplied in less than about 5 minutes. Before and after each treatment, the number of lice is counted on 5-10 fish and the degree of delousing is calculated. The results of the tests appear in Table 2. The number of salmon lice before and after each treatment is given as a mean value. Table 2: control of salmon lice

Claims

1. Composition, whereby the weight ratio of hydrogen peroxide to sorbitol is comprised between 5:1 and 7:1.

2. Composition according to claim 1 , whereby the weight ratio of hydrogen peroxide to sorbitol is about 6.7

3. Composition according to claim 1 or 2, whereby sorbitol is D-sorbitol.

4. Use of a composition comprising hydrogen peroxide and sorbitol in an aqueous medium comprising an aquatic animal and/or aquatic plant.

5. Use according claim 4, whereby said aquatic animal is a fish.

6. Use according to any of the above claims, whereby the weight ratio of hydrogen peroxide to sorbitol is comprised between 1 :1 and 10:1.

7. Use of a composition comprising hydrogen peroxide and sorbitol for the control of an infection in an aquarium, wherein the composition is added directly to water in the aquarium without first removing aquatic animals or plants from the aquarium.

8. Use of a composition comprising hydrogen peroxide and sorbitol for controlling algae growth in aquaria.

9. Use of a composition comprising hydrogen peroxide and sorbitol for controlling parasites on fish.

10. Use of a composition comprising hydrogen peroxide and sorbitol for hatching Artemia cysts.

11. Use of a composition as in claims 1 to 3 for use as in claims 8-10.

12. Method for controlling an infection in an aquatic environment, comprising the steps of: a) placing an aquatic animal in water b) supplying the water with hydrogen peroxide or a hydrogen peroxide- producing substance and sorbitol

13. Method according to claim 12, whereby in the water the ratio of hydrogen peroxide to sorbitol is comprised between 1 :1 and 10:1.

14. Method according to claim 12 or 13, whereby said aquatic animal is a fish.

15. Method according to any of the above claims, whereby said infection is a microbial infection and/or a bacterial infection or and/or an infection with algae.