Claims:1. A method for enhancing the growth of a prokaryote by selectively controlling eukaryotic grazers and/or eukaryotic contaminants in an aquatic environment, said method comprising contacting the eukaryotic grazers and/or eukaryotic contaminants with a pre-determined amount of Cycloheximide, without affecting the growth of the prokaryotes.

2. The method as claimed in claim 1, wherein the prokaryote is cyanobacteria.

3. The method as claimed in claim 1, wherein the eukaryotic grazers and/or eukaryotic contaminants is at least one selected from the group consisting of diatoms, rotifers, ciliates and fungi.

4. The method as claimed in claim 1, wherein the pre-determined amount of Cycloheximide is in the range of 1 ppm to 25 ppm of the medium in the aquatic environment, preferably the amount of Cycloheximide is 10 ppm of the medium in the aquatic environment.

5. The method as claimed in claim 4, wherein the medium is at least one of fresh water and sea water.

6. The method as claimed in claim 1, wherein the aquatic environment is at least one selected from the group consisting of outdoor pond, tank for commercial aquaculture, pond for commercial aquaculture, aquarium, photo-bioreactor and combinations thereof.

7. The method as claimed in claim 1, wherein the pH of the aquatic environment is in the range of 6.5 to 7.5. , Description:FIELD
The present disclosure relates to a method for selectively controlling the growth of eukaryotes.
BACKGROUND
Prokaryotes, such as, cyanobacteria, are potential source for generation of renewable energy by converting sunlight into electricity. For the generation of sustainable energy from prokaryotes, large scale cultivation of prokaryotes is required. Eukaryotic grazers and contaminants are a major concern in the cultivation of prokaryotes. Ciliates, rotifers and diatoms compete with the prokaryotes, resulting in reduced production of the prokaryotic biomass. Various chemicals are known, which can be used to kill the eukaryotic grazers and contaminants, however, these chemicals have a deleterious effect on the prokaryotic growth also. Therefore, there is felt the need for a method for selectively killing/inhibiting the growth of eukaryotes in the cultivation of prokaryotes.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows.
It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
An object of the present disclosure is to provide a method for enhancing the growth of a prokaryote.
Another object of the present disclosure is to provide a method for enhancing the growth of a prokaryote by controlling eukaryotic grazers and/or eukaryotic contaminants in an aquatic environment.
Still another object of the present disclosure is to provide a simple and economical method for enhancing the growth of a prokaryote.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to a method for enhancing the growth of a prokaryote by selectively controlling eukaryotic grazers and/or eukaryotic contaminants in an aquatic environment. The method comprises contacting the eukaryotic grazers and/or eukaryotic contaminants with a pre-determined amount of Cycloheximide. Cycloheximide selectively kills the eukaryotes without affecting the prokaryotes therefore, application of Cycloheximide leads to elimination of eukaryotic grazers and/or eukaryotic contaminants and increased production of the prokaryotic biomass.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The disclosure will now be described with reference to the accompanying non-limiting drawings, wherein:
Figure 1 illustrates an image of Cyanobacterium aponinum cells prior to being added into an open pond;
Figure 2 illustrates an image of Cyanobacterium aponinum cells growing in the absence of Cycloheximide, contaminated with diatoms, in an open pond;
Figure 3 illustrates an image of Cyanobacterium aponinum cells growing in the presence of Cycloheximide in an open pond;
Figure 4A illustrates an image of Cyanobacterium aponinum cells growing in the absence of Cycloheximide, contaminated with rotifers, in an outdoor pond;
Figure 4B illustrates an image of Cyanobacterium aponinum cells growing in the absence of Cycloheximide, contaminated with ciliates, in an outdoor pond;
Figure 4C illustrates an image of Cyanobacterium aponinum cells growing in the absence of Cycloheximide, contaminated with diatoms, in an outdoor pond; and
Figure 4D illustrates an image of Cyanobacterium aponinum cells growing in the presence of Cycloheximide, in an outdoor pond.
DETAILED DESCRIPTION
The disclosure will now be described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
Prokaryotes are the source of various chemicals/compounds having useful commercial applications. Prokaryotes have been used traditionally for production of food, such as yogurt, sauerkraut, sausages, vinegar, and the like. Prokaryotes can be easily manipulated and therefore, genetic engineering has made it possible to obtain human insulin, antibiotics, plant hormones, and industrial solvents from prokaryotes. Recently, cyanobacteria have emerged as a potential source for the generation of renewable energy by converting sunlight into electricity. One major concern in the large scale cultivation of prokaryotes, such as, cyanobacteria is the eukaryotic contamination resulting in significant reduction in the growth of the prokaryotes.
Attempts have been made to kill the eukaryotes by application of chemicals, however, the chemicals used harm the prokaryotes also, which is not desired.
Accordingly, the inventors of the present disclosure have envisaged a method for enhancing the growth of a prokaryote by selectively controlling eukaryotic grazers and/or eukaryotic contaminants in an aquatic environment. The method comprises contacting the eukaryotic grazers and/or eukaryotic contaminants with a pre-determined amount of Cycloheximide, without affecting the growth of the prokaryotes.
Cycloheximide is an inhibitor of protein biosynthesis in eukaryotic organisms, produced by the bacterium Streptomyces griseus. Cycloheximide exerts its effect by interfering with the translocation step in protein synthesis (movement of two tRNA molecules and mRNA in relation to the ribosome) thus blocking translational elongation. Cycloheximide stops the translation of messenger RNA on cytosolic 80S ribosomes, but does not inhibit organelle or prokaryotic protein synthesis. Thus, Cycloheximide has the capacity to potentiate the control of eukaryotic grazers and/or eukaryotic contaminants in a prokaryotic cultivation environment.
The inventors of the present disclosure have, therefore, used the selective inhibition activity of Cycloheximide to control eukaryotic grazers and/or eukaryotic contaminants in an aquatic environment.
The amount of Cycloheximide used in the present disclosure is in the range of 1 ppm to 25 ppm of the medium in the aquatic environment. In an exemplary embodiment of the present disclosure, the amount of Cycloheximide is 10 ppm of the medium in the aquatic environment.
In an embodiment of the present disclosure, the prokaryote is cyanobacteria.
Cyanobacteria are capable of growing in fresh water and sea water. Accordingly, the medium used in the method of the present disclosure can be fresh water or sea water.
In accordance with the embodiments of the present disclosure, the eukaryotic grazers and/or eukaryotic contaminants is at least one selected from the group consisting of diatoms, rotifers, ciliates and fungi.
In accordance with the embodiments of the present disclosure, the aquatic environment is at least one selected from the group consisting of outdoor pond, tank for commercial aquaculture, pond for commercial aquaculture, aquarium, photo-bioreactor and combinations thereof.
The pH of the aquatic environment is maintained in the range of 6.5 to 7.5.
In an exemplary embodiment of the present disclosure, Cyanobacterium aponinum are grown in the absence and in the presence of Cycloheximide (10 ppm). The salinity in the pond is maintained at 4 % and the pH in the pond is maintained at 7.5. Figure 1 illustrates the image of Cyanobacterium aponinum cells prior to being added into the open pond; Line A indicates the Cyanobacterium aponinum cell. The biomass of Cyanobacterium aponinum is significantly reduced when cultivated in an open pond in the absence of Cycloheximide as illustrated in Figure 2; Line A indicates the Cyanobacterium aponinum cell and Line B indicates diatom. However, when Cyanobacterium aponinum cells are cultivated in the presence of Cycloheximide, the diatoms are selectively killed, resulting in a significant increase in the Cyanobacterium aponinum cells, as illustrated in Figure 3; Line A indicates the Cyanobacterium aponinum cell. Figures 4A, 4B and 4C illustrate the Cyanobacterium aponinum cells contaminated with rotifers, ciliates and diatoms respectively, when cultivated in the absence of Cycloheximide; Line A indicates the Cyanobacterium aponinum cell, Line C indicates ciliate cell, Line D indicates rotifer cell. Figure 4D illustrates the cultivation of Cyanobacterium aponinum in an outdoor pond in the presence of Cycloheximide.
It is clearly seen from the above mentioned figures that adding Cycloheximide to the pond results in efficient control of the eukaryotic grazers and/or eukaryotic contaminants. Further, the addition of Cycloheximide did not have any detrimental effect on Cyanobacterium aponinum cells and thereby resulting in an improved production of Cyanobacterium aponinum cell.
TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE
The method of the present disclosure described herein above has several technical advantages including, but not limited to, the realization of:
? outdoor cultivation of cyanobacterial without culture crashes due to contamination by ciliates, rotifers and diatoms;
? simple and economic method for enhancing the growth of a prokaryote by controlling the eukaryotic growth; and
? large scale production of cyanobacteria devoid of any eukaryotic contamination.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values ten percent higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.