KR101810782B1 - Method for massive culture of adhesive microalgae - Google Patents

Abstract

The present invention relates to a method of culturing a large amount of adhesive Bacillariophyta. The method includes: a step (a) of attaching adhesive Bacillariophyta such as Achnanthes brevipes var.intermedia, Achnanthes sancti-pauli, and Melosira octogona by forming an adhesive substrate on the floor of a water tank of a predetermined volume to be perpendicular to the surface of the floor and collecting and connecting seawater of Jeju-do to the water tank; a step (2) of moving the adhesive substrate attached with the adhesive Bacillariophyta to an outdoor water tank and culturing the adhesive Bacillariophyta with sunlight; a step (3) of separating the adhesive Bacillariophyta from the adhesive substrate by supplying bubbles from the bottom of the substrate; and a step (4) of floating the adhesive Bacillariophyta on the surface of the water by using phototaxis of the separated adhesive Bacillariophyta, and collecting the adhesive Bacillariophyta by using a water current. As such, the method is capable of culturing a large amount of adhesive Bacillariophyta, which is highly valuable as basic materials for various industries, with low energy and resources.

Description

METHOD FOR MASSIVE CULTURE OF ADHESIVE MICROALGAE FIELD OF THE INVENTION [0001]

The present invention relates to a method for separating and culturing adherent diatoms from seawater in a specific area. More particularly, the present invention relates to a process for separating adherent diatoms from lava seawater distributed on the east coast of Jeju Island, a method for mass culturing separated diatoms under certain conditions, and harvesting cultured adherent diatoms And a method for separating and culturing adherent diatoms.

In Korea, research on microalgae including phytoplankton began to be active in the late 1960s and spread to physiological ecology, biochemistry, genetic engineering and biotechnology since the late 1980s. Since then, it has been expanding to applications such as environment and life industry.

Microalgae is a producer of organic matter from minerals using solar energy in the ocean. It is an important food for marine ecosystems such as zooplankton and fish, Respectively. Microalgae can vary from green algae to red algae and cyanobacteria depending on the kind of chlorophyll contained.

The microalgae, which are currently being produced commercially, are mainly cultured using a photobioreactor capable of culturing at a high density. In a conventional photobioreactor, a culture medium is supplied according to the type of microalgae to be cultivated in a constant volume tank, microalgae are inoculated, and then pure culture is carried out by blocking the infestation of protozoa and molds harmful to the growth of microalgae The culture solution is filtered and sterilized.

A gas containing a carbon source such as carbon dioxide is aerated in the culture solution so that sufficient photosynthesis can be achieved, and the gas and the nutrients in the culture solution are stirred to be uniformly dispersed. For efficient photosynthesis, light of a certain wavelength is irradiated using an LED or the like depending on the characteristics of the microalgae to be cultured. Particularly, in a photoreactor, it is necessary to maintain a culture liquid at a constant temperature in order to cultivate microalgae in a large amount with a constant growth efficiency. Therefore, a heating apparatus, a heat exchanger, and the like are installed and cultivated according to the season.

Therefore, there is a problem that a large amount of energy is consumed in the mass cultivation of microalgae due to the supply and aeration of the culture medium, the irradiation of light through the light source, and the control of the water temperature. In particular, in the case of the four seasons in Korea, Is a problem in energy efficiency.

Meanwhile, as shown in Figure 1, the Lava Seawater is seawater flowing through the basalt layer of Jeju Island and flowing into the ground underground. Lava seawater is found in some parts of western part of Jeju Island and eastern part and contains high concentration of minerals. In addition, while general seawater is exposed to unstable environment such as domestic sewage, industrial wastewater, and port pollution, it takes a lot of cost to process industrial material, while lava seawater is subjected to natural purification and filtration by volcanic rock layer to block heavy metal adsorption and harmful substances Therefore, safety, stability, and economic efficiency are ensured, and the water intake cost is inexpensive as compared with deep seawater taken from the deep sea.

The inventors of the present application have confirmed that adherent diatoms are collected together with lava sea water in the process of culturing using Jeju lava seawater, and established a method of mass-culturing these adherent diatoms dominantly. Adhesive diatoms that have been identified in the present invention can be used as a feed alternative energy source in the aquaculture industry or as a valuable resource as a basis for various industrial fields such as medicine, environment, and life industry.

Korean Patent No. 10-1278146 discloses a hot water discharge pipe for discharging hot water from a power plant or a factory, a hot water pipe connected to the hot water discharge pipe for transferring hot water, a hot water pipe connected to one side, And a cooling water pipe connected to the other side of the water tub to transfer the cooling water from the water tub. Korean Patent Registration No. 10-1241393 discloses a photobioreactor having a culture panel body provided with a culture space, a culture medium supply unit adapted to supply the culture medium into the culture medium body, and a culture medium supply unit for withdrawing the culture medium from the culture medium body and diluting the culture medium with the diluent. A concentration detecting section for measuring the concentration of the diluted culture liquid diluted by the dilution section, and a dilution section and a concentration detection section are controlled to receive the concentration information of the dilution culture liquid. If the concentration of the received dilution culture liquid is not less than the set target concentration And a control unit for controlling the production of microalgae while controlling the medium to be supplied to the culture panel body by controlling the medium supply unit so that the culture liquid stored in the culture panel body is discharged through the storage line, Discloses an automated system for feeding a reactor medium. Korean Patent Laid-Open Publication No. 10-2012-0095826 discloses a method for treating carbon dioxide such as Scenedesmus sp., Chlorella sp., Spirulina sp., And the like, as well as treating biodiesel, feed additives, Discloses a photobioreactor for micro-algae high-density culture capable of realizing low-cost, high-quality, and mass-production of microalga useful in production, and a microalgae culture and harvesting method using the same. Korean Patent Registration No. 10-1256773 discloses a method for producing a wastewater treatment or biomass comprising culturing microalgae using mixed light of red light and blue light as a light source, And the amount of nitrogen and phosphorus removal can be increased. In particular, as the red light source and the blue light source, a wastewater treatment method using microscopic algae using wavelength selective LED light irradiation using a low power consumption type LED (light emitting diode) and a method for increasing productivity of microalgae biomass are disclosed. However, the above-mentioned inventions are different from the method of mass-culturing adherent diatoms of the present invention, which includes a step of attaching micro-algae in natural seawater and mass-culturing and then harvesting microalgae using daylighting.

It is necessary to establish the species selection and culture method which can be used as an excellent feed source in the aquaculture style with ease in large scale cultivation among the adherent diatoms. This study provides a method for identifying adherent diatoms contained in lava sea water during cultivation using Jeju Lava Seawater and mass-culturing these adherent diatoms as dominant species.

In order to solve the above-mentioned problems, the present invention provides a method for producing a water-soluble diatomaceous earth including the steps of (1) forming an adhering substrate horizontally on a bottom surface of a tank having a predetermined volume, (2) a step of moving the adhered substrate attached with the adhesive substrate to the outdoor water tank and culturing the adhesive substrate with sunlight; (3) removing the adherent diatoms cultured in the adhesive substrate by supplying air bubbles below the adhered substrate; (4) suspending the water-absorbing diatomaceous earth on the surface of the water by using the light-shielding property and recovering the water by using water currents.

According to the present invention, there is provided an eco-friendly large-scale cultivation method of sticky diatoms capable of separating adhering diatoms taken with Jeju lava seawater through a mass culture method of sticky diatoms according to the present invention and mass- Segregated diatoms that have been confirmed to be detached can be used as a feed alternative energy source for the aquaculture industry or as a valuable resource for various industrial fields such as medicine, environment, and life industry.

1 shows the location and general description of the distribution of lava water in Jeju Island. ()
Figure 2 shows the comparison of the characteristics of lava water distributed in Jeju Island with general sea water. (http://jejutp.or.kr/lavawater/whatis/what.htm)
Fig. 3 is a graph showing the distribution of the attached diatoms Achnanthes brevipes var. It is an optical microscope photograph of intermedia (A), Achnanthes sancti-pauli (B) and Melosira octogona (C).
Fig. 4 is a graph showing the distribution of Ahnanthes brevipes var. intermedia (A), Achnanthes sancti-pauli (B) and Melosira octogona (C).
FIG. 5 is a photograph showing the recovery process of attached diatoms using daylight.
6 is a photograph showing the recovery process of the attached diatoms using the net collecting device.

In general, adherent diatoms are the primary producers of organic matter from photosynthesis and are commonly used as food organisms in aquaculture. It is mainly fed from aquaculture water and grows attached to aquaculture tank or cultivated phalanx to be fed to aquatic animals. Especially, it is a food of abalone such as abalone, seashell, bivalve such as shellfish, echinoderm such as sea cucumber, sea urchin, It is used as an early food organism when raising larvae. These adherent diatoms are mainly grown in natural seawater by attaching them to wings for attachment of aquaculture animals such as polycarbonate or polyvinyl chloride.

However, the culture of adherent diatoms is difficult to mass-produce because of the adherent nature of the culture method of conventional floating microalgae. That is, as the microalgae grow by attachment and growth, the light transmission rate by self-shading decreases, the growth of microalgae becomes stagnant, and the number of dead cells increases, and there is a problem that microalgae There is also difficulty in collecting.

On the other hand, some parts of western part of Jeju Island and the eastern part are thickly distributed from the surface of the volcanic rock formed by hardening of lava to about 150m below the sea surface. The rock layer occupies a high percentage of pores capable of storing groundwater, (Fig. 1). The Seogwipo layer under the volcanic rock is supported by the thick lava seawater layer in the volcanic rock layer as a low permeable layer and the boundary and junction between the glassy clastic breccia and the lava flows in the volcanic rock layer are composed of saltwater groundwater It is easy to make it. Jeju Lava Seawater is buried at a depth of 70m or more underground and is completely isolated from germs, barns, and hazardous chemicals, but contains a larger amount of minerals than ordinary seawater (Fig. 2).

As shown in FIG. 2, the number of general microorganisms was found to be 60,000 CFU / ml in general seawater, but was not detected in lava seawater.

In the present invention, microorganisms collected with clean lava sea water are separated and identified, and thus , Fragilariopsis sp. And Melosira nummuloides and Melosira octogona and establishing a mass culture method in which the adherent diatoms can be cultivated as a dominant species. In application No. 10-2016-0042696, separation of adherent diatoms from lava seawater in Jeju Island, Ahnanthes brevipes var. From the Jeju Lava Seawater was investigated . intermedia , Achnanthes sancti-pauli and Melosira octogona were further separated and identified, and their mass culture methods and methods were established.

1. Acquisition of Adherent Diatoms from Lava Seawater

The temperature of cultured marine aquatic diatoms is 16-24 degrees and the salinity is 25 ‰ or higher. In the case of underground seawater distributed in Jeju Island, it maintains 17-18 and 25 ‰ during the year. Condition. In particular, when lava seawater is continually communicated, it is possible to maintain the water temperature change in the open hearth above 17 degrees in the winter season and below 24 degrees in the summer season. Therefore, considering that the marine- This is possible.

The inventors of the present invention have confirmed that phytoplankton is taken together with the lava waters in the process of biological examination, and as a result, it has been found that Achnanthes brevipes var. intermedia and Achnanthes sancti-pauli and Melosira octogona . These phytoplankton species are not well known in the country for industrial use and are only reported to be found in the UK, Taiwan, Australia, New Zealand and Alaska.

The above Achnanthes brevipes var. Intermedia , Achnanthes sancti-pauli and Melosira octogona are included in the adherent diatoms separated by 2-4 cells / L in the initial lava water inflow, and they can be visually confirmed by attaching them to the 5-period drawings through the attached substrate (nylon net) Do.

Fig. 3 is a graph showing the distribution of the attached diatoms Achnanthes brevipes var. intermedia (A), Achnanthes sancti-pauli (B) and Melosira octogona ( C) And FIG. 4 is a scanning electron micrograph thereof. Based on the trial and error, the identified adherent tidal algae could be cultured in the following manner.

(1) Preparation of water tanks (or nogi) with microalgae

Adherence Prepare a tank in a location where it is easy to supply lava water for diatom cultivation. The water tank should have a flat bottom of 3 ~ 6 m × 5 ~ 10 m × 0.5 ~ 1.5 m in width, length and depth so that lava seawater is poured at one end of the water tank and drained at the other end so that a constant water flow is formed in the water tank do. The velocity of lava seawater is determined by the volume of water received by the pump and the size of the tank, and is adjusted taking into account the amount of time that the adherent gypsum can attach to the adhered substrate sufficiently. Therefore, it takes 2 to 4 rounds of lava seawater per day, and it is adjusted to about 2 rotations in summer and about 4 rotations in winter.

It is preferable that a barrier membrane is laid on the hearth in order to prevent the inflow of pathogenic microorganisms from the bottom of the hearth when the adherent anchovy is adhered in the open hearth instead of the attachment bath.

(2) Attachment substrate

In order to obtain anchovy from the lava seawater, the adherent substrate to which the adherent algal algae can attach is placed on the bottom of the aquarium (or the ooze). The bonding efficiency of the nylon mesh (0.1 mm) was the best for the adhered substrate. The larger the mesh size, the lower the adherence efficiency of the adherent type algae. If the mesh size is smaller than that, It was not easy. Adhesive substrate material can be used as nylon, PP, or PE, but nylon has the highest attachment rate of sticky gypsy. The adhesive substrate spreads wide on the bottom of the attachment bath and the edge is fixed to the bottom of the wall. Or the attachment substrate may be fixed to the frame. After the adherence to the adherent substrate, the adherent adherent tyrosinase begins to multiply and oxygen generated by the photosynthetic action of the adherent adenovirus migrates into the water and collects below the bottom of the adhered substrate, causing the adherent substrate to float from the bottom surface do.

In this case, the adherent tidal algae in which the adhered substrate is exposed outside the seawater may dry out, or parasitism may propagate. Therefore, in order to prevent the adhered substrate from floating, a cross-shaped or straight-shaped incision is made in the attached substrate at an interval of 0.5 to 1 m so as to allow the gas produced by the adherent tidal flow to be discharged. A grid wire spaced 3 to 5 m apart on top of the adhered substrate prevents the adhered substrate from flooding. When the attachment substrate is installed and the attachment substrate is attached to the attachment substrate for about 4 to 5 days, attachment of the adhesion film is completed and the attachment substrate is transferred to the culture tank for mass culture.

2. Adherence Mass culture of diatoms

(1) Attachment Attachment Species composition

Adhesive diatoms have a wide variety of diatoms, among which adherent diatoms used in abalone culture are mainly Cocconeis sp., Melosira sp. Navicula britannica , Navicula sp. Navicula closterium , Navicula longissima , Navicula marina , Navicula sp. And it is divided into a crawling type, an upright type, and a Matrix type according to the growing position, and there is a kind which has a multiplicity of growth or a colony growth, a mobility and a lack thereof, and a very fast mobility.

Adult diatoms obtained from Lava Seawater in Cheju Island have been tested by Achnanthes brevipes var. Fragilariopsis sp., Melosira nummuloides , intermedia , Achnanthes sancti-pauli and Melosira octogona were dominant species, and thus it was advantageous to establish large-scale cultivation conditions of the adherent gusts obtained from lava seawater.

I have Achnanthes brevipes . intermedia , Achnanthes sancti-pauli and Melosira octogona were excellent in cold water, and were cultivated throughout the year and were well-nourished and suitable for feeding on abalone and sea cucumber.

(2) Attachment Attachment Large-scale culture of algae

Lava seawater distributed in Jeju Island maintains 17-18 degrees during the year, and it is possible to maintain more than 17 degrees in winter and 24 degrees in summer. Salinity is also maintained at least 25 ‰ throughout the year, so it is possible to cultivate attached diatoms throughout the year.

Table 1 shows the changes in the attached diatomaceous floatation state according to the measured daily illuminance and cloudiness in the spring.

Variation of the attached diatomic flotation condition with daily illuminance and cloudiness time Illumination (Lux) Attached diatomic floating state Cloudiness Remarks 07:00 4400 - 0 08:00 22700 - 0 09:00 21100 + One 09:40 59500 ++ 0 15:00 33500 +++ 4 16:30 22300 +++ 4 17:30 9700 +++ 18:30 2700 - July 17, 2013 07:30 9500 - One 08:30 31900 + One 09:30 67200 ++ One 10:30 90100 +++ One 14:00 105100 +++ One 17:00 56400 +++ One 18:00 49500 +++ One 19:00 27200 + One

1) cloudiness; 0 (cloud 100%), 1 (80-90%), 2 (60-80%), 3 (40-60%), 4 (10-40% condition ; + (Little), ++ (many), +++ (very many)

The mass culture of the attached diatoms according to the present invention is basically based on outdoor cultivation using sunlight. In the case of Jeju Island, natural light is generally maintained at more than 4,000Lux at sunrise and more than 2,000Lux at sunset, and the maximum daylighting capacity is 100,000Lux in Jeju Island. Considering that the sunrise time is 9 hours and 30 minutes for the winter time and 14 hours and 45 minutes for the winter time, sunlight is irradiated to the fine - grained diatomite more than 12 hours a day.

Considering that the life cycle of the common adhesive diatoms is up to 14 days, the life of fine algae is shortened during the summer when the growing conditions are better, and the production is increased.

3. Recovery of mass cultured adherent diatoms

(1) Separation of adherent adherent algae using air bubbles

Adherence to the adherent matrix As the biomass increases over time, the algae are detached from the adherent matrix and separated from the adherent matrix, forming colonies. The remaining adherent gradients that are not detached from the adhered substrate can be separated from the adhered substrate using an air compressor or compressed air. Adhesive agglomerates separated from the adhered substrate become suspended in the culture tank.

(2) Recovery of adherence to algae by using daylight

Adhesive agglomerates separated from the adherent matrix float in the water tank, and Fragilariopsis sp. And Melosira nummuloides and Achnanthes brevipes var. intermedia, Achnanthes sancti-pauli and Melosira octogona constitute more than 99%, and these species have light-shielding properties. I have Achnanthes brevipes . intermedia , Achnanthes sancti-pauli and Melosira octogona show strong daylight at higher than 30,000 Lux, so they float on top of the tank during daytime, as shown in Table 1. At this time, by installing the stand along the water stream, the attached diatom mass can be recovered by collecting the floating diatomaceous earth mass, thereby recovering the sticky gypsy algae without using any other energy source.

FIG. 5 is a photograph showing the recovery process of attached diatoms using daylight. Increase of Cloud Amount During Collection If the lightness of 30,000 Lux or more can not be obtained due to the weather change or the like, 30,000 Lux light as an external light source can float on the side of the upper part of the culture tank to float the floating sticky diatomaceous mass. When the wood or PCV pipe is cut along the length, the agglomerations of the agglutinated grains are gathered along the water stream continuously formed in the culture tank during the cultivation.

6 is a photograph showing the recovery process of the attached diatoms using the net collecting device. Adherable diatomaceous masses that flocculate along the water stream can be easily collected by filtering by a collection device including a nylon net (mesh size: 0.1 mm).

The collected adherent diatoms can be used as they are in wet form, or after drying and grinding, through feed and feed additives, or through secondary processes, in applications such as the environment and life industry.

(3) Annual adhesive diatom yield according to the present invention

Table 2 is a table showing the annual production of adherent diatoms by the mass culture method of the attached diatoms according to the present invention. According to one embodiment of the present invention, an adhering strain algae was adhered to a 54 m ² adherent substrate and cultured. As a result, the average amount of adhered diatomaceous annual production was as follows: fine adhered diatomic colony with a water content of less than 50% ) 85.6g / ㎡, which shows productivity of 31.1kg / ㎡ per year. This result is remarkably superior to other studies (Korea Research Institute of Marine Science and Technology, 14.4 kg / ㎡, 2012) using pseudo-adherent tyrosinous algae, and shows high productivity with very little energy by the large-scale culture of adhered diatoms according to the present invention Respectively.

The annual production of adherent diatoms by the mass culture method of the attached diatoms according to the present invention year month 2012.
10. 11 12 2013.
10. 2 3 4 5 6 7 8 9 Month total
Recovery (kg) 1,348 869 703 1,290 790 1,842 1,125 1,120 1,455 1,440 2,890 2,060 Daily average recovery (g /) 80.53 53.64 42.00 77.06 52.25 110.04 69.44 66.91 89.81 86.02 172.64 127.16

The present invention provides a method for mass-culturing adherable diatoms, which is capable of easily adhering adherent diatoms, multiplying adherent diatoms, and cultivating them in large quantities and recovering them easily, through a mass culture method of adherable diatoms according to the present invention. It is possible to use it in industry.

Claims (5)

Installing a nylon net having a cross or a straight cut at an interval of 0.5 to 1 m horizontally in an attaching water tank having a predetermined volume;
Ahnanthes brevipes var. Var. Anchovy, which is collected at 2-4 cells / L together with lava seawater in Jeju island, intermedia , or Achnanthes sancti-pauli or Melosira octogona to the nylon mesh ;
And a method of mass-culturing adherent diatoms by separating adherent diatoms from the lava waters of Jeju Island using the solar light. delete delete delete delete

Images