CN118064250A - A multifunctional microbial screening and cultivation system - Google Patents

Abstract

The present invention discloses a multifunctional microorganism screening and culturing system, which consists of a double-sided culture dish, a detachable photocopy plate and an in-situ culture tank. The system simulates the interaction process between two or more microbial strains in nature, simulates the natural growth environment, realizes the co-culture between microbial strains and the in-situ culture of microorganisms, and is easy to separate and purify target strains in the later stage, screen uncultured microorganisms, and explore the interaction mechanism between microbial strains.

Description

A multifunctional microbial screening and cultivation system

Technical Field

The invention relates to the technical field of microbial separation and cultivation, and in particular to a multifunctional microbial screening and cultivation system.

Background technique

Existing studies on microbial molecular ecology have shown that the ocean contains a large number of microbial resources, which are of great significance to the earth's material cycle, ecological balance and human health. However, the vast majority of microorganisms cannot be isolated and cultured using existing culture methods and technologies, and these microorganisms are called uncultured microorganisms.

Under traditional laboratory conditions, microorganisms are usually cultured under conditions of simple nutrient matrix, constant ventilation, temperature, pH and other parameters, ignoring the effects of interactions such as the exchange of metabolic products and signal transmission between microbial cells on the growth of other species. As a result, many microorganisms lose the necessary conditions for growth and appear to be uncultured.

Co-culture and in situ culture separation technologies have emerged. At present, domestic and foreign scholars have developed a variety of co-culture and in situ culture technologies. Most of them use microporous filter membranes, nanomaterials and nutrient matrices to achieve isolation between the environment and strains, and between strains, which has improved the exploration and research of uncultured microorganisms to a certain extent. However, there are still the following defects in general: (1) The technical operation is relatively complicated and difficult to repeat and popularize; (2) It is easy to cause pollution and it is difficult to separate and purify potential new strains to be separated; (3) The separation device is difficult to make or the cost is high, and the culture environment and equipment requirements are strict; (4) The embedding of microbial cells will change the gas environment around the cells, affect their growth state, and reduce or change the production of metabolites.

Summary of the invention

In view of the deficiencies in the prior art, the present invention provides a multifunctional microbial screening and cultivation system, which simulates the interaction process between two or more microbial strains in nature, simulates the natural growth environment, realizes co-cultivation between microbial strains and in situ cultivation of microorganisms, and is easy to separate and purify target strains in the later stage, screen uncultured microorganisms, and explore the interaction mechanism between microbial strains.

In order to achieve the above object, the technical solution adopted by the present invention is as follows:

A multifunctional microorganism screening and culture system: including a double-sided culture dish, a detachable photocopy plate and an in-situ culture tank, characterized in that: the double-sided culture dish is composed of a dish body, a blocking inner cover, a dish cover A, and a dish cover B; the dish body is composed of an outer rubber strip, a side wall, a fixing module, a support net, a limiting column, and a waterproof strip; the outer rubber strip is fixed to the middle position outside the side wall in a detachable manner; the support net is fixed to the middle position inside the dish body through the fixing module and is sealed with the side wall; the limiting column is located in the upper half of the side wall and is marked with a serial number; the waterproof strip is located in the lower half of the side wall near the supporting net; the blocking inner cover is located in the lower half of the dish body; the dish cover A is located above the dish body; The cover B is opposite to the dish cover A and is connected to the dish body through an outer rubber strip. The outer surface of the dish cover is provided with a circle of anti-slip rubber ring, and the inner surface of the dish cover is provided with a circle of water storage strip; the detachable photocopy plate is placed on the upper part of the dish body, and is composed of a handle, a supporting foot and a photocopy plate; the edge of the photocopy plate is provided with four limit grooves, which are marked with serial numbers and correspond to the limit columns one by one; the in-situ culture tank is used in conjunction with the double-sided culture dish, and is composed of a sealing cover, a tank body and a storage rack; the sealing cover is composed of a handle, a vent valve and a buckle; the inner and outer sides of the tank body are provided with water inlet holes and water outlet holes, respectively, and the side wall is provided with water inlet and outlet pipes for water flow to pass through; the top ends of the water inlet and outlet pipes in the side wall are located at the edge of the tank body opening and are sealed by screws;

Preferably, the outer rubber strip is detachably fixed to the middle position outside the side wall, and is divided into a sealing rubber strip and a breathable rubber strip. The breathable rubber strip has some vents to allow gas exchange inside and outside the device, while controlling the loss rate of water in the internal culture medium.

Preferably, the inner surface of the upper half of the side wall is numbered corresponding to the transverse and longitudinal grids of the support net, so as to facilitate the positioning of the bacterial colonies on the surface of the culture medium;

Preferably, the waterproof strip is annular and is embedded inside the culture medium after the culture medium solidifies to prevent liquid from leaking from the edge;

Preferably, the sealing inner cover is truncated cone-shaped, and its inner diameter is the same as the inner diameter of the dish body, and is divided into three types: sealing, breathable and replacement; the sealing type has a smooth inner surface, and the breathable type has an inner surface made of a support frame and a bacterial filter membrane or filter paper and other materials. The sealing and breathable sealing inner covers have various specifications, and the corresponding specifications of the sealing inner covers can be selected according to the thickness of the culture medium preparation, the amount of sample added, and the nature of the sample, according to the serial number indication on the lower half of the inner side wall; the replacement type sealing inner cover has two one-way water stop valves on the outer surface, which can be connected to an external circulation device to allow liquid samples to flow in from one side and out from the other side, and is mainly used for in situ culture; the three types of sealing inner covers are sealed and connected to the dish body through the card grooves on the edges, and there are sealing patterns in the card grooves to prevent leakage.

Preferably, the dish body and the dish cover are made of transparent materials that can be sterilized at high temperature, such as PC plastic, PP plastic and glass;

Preferably, the supporting net in the middle of the culture dish body is made of a material that can be sterilized at high temperature and has a certain supporting strength, such as nylon material, stainless steel, and high temperature resistant plastic.

Preferably, the fixing module can be made of high temperature resistant materials such as rubber, silicone, plastic, etc., which can play the role of fixing the middle support net.

Preferably, the anti-skid rubber ring on the outer surface of the dish cover can be made of high temperature resistant anti-skid materials such as silicone, rubber, etc., and is embedded in the card groove on the outer surface of the dish cover and is detachable.

Preferably, the water storage strip on the inner surface of the dish cover can be composed of sponge, absorbent paper, absorbent cloth, etc., and is embedded in the slot on the inner surface of the dish cover and is detachable.

Preferably, the dish cover B is divided into two types, with and without notches, according to whether there is a notch in the side wall. The dish cover with a notch is used in conjunction with the in-situ culture tank, and the side notches facilitate the connection of the water pipe to the replacement-type plugging inner cover and the water inlet and outlet inside the in-situ culture tank. At the same time, its height is slightly higher than that of the dish cover A, and it is inverted on the upper part of the double-sided culture dish to play a supporting role, so that multiple double-sided culture dishes can be stacked in the in-situ culture tank; the dish cover B without a notch has the same structure as the dish cover A, and is used during co-culture and partial in-situ culture.

Preferably, the detachable photocopy plate has five supporting feet, with magnetic materials at the top of the supporting feet, and a telescopic rod in the middle that is retractable. The bottom end of the telescopic rod is kept horizontal with the other four supporting feet in a static state, so that the photocopy plate can be evenly stressed when photocopying the bacterial colonies on the surface of the culture medium; the handle is connected to the supporting feet through screw holes, so that the supporting feet can be easily replaced when they are damaged; the support frame can be separated from the photocopy plate by pressing a button, so that the photocopy plate can be easily replaced.

Preferably, the diameter of the photocopy plate is the same as the inner diameter of the dish body, and is divided into an upper and lower surface. The edge of the upper surface has five slots, and the slots contain magnetic materials that are adsorbed and connected to the support feet. The lower surface is made of shorter cilia or gauze or other materials that are easy to adhere to bacteria.

Preferably, the sealing cover is sealed and connected to the tank body in a snap-fit manner, and a vent valve is provided on the sealing cover, which can not only seal the in-situ culture tank to achieve anaerobic culture, but also connect the inside and outside to perform aerobic culture. When the vent valve on the sealing cover is closed for anaerobic culture, it is best to use an anaerobic bag to remove oxygen in the tank, and do not use an instrument to extract the internal oxygen, so as to avoid damage to the double-sided culture medium due to excessive changes in internal and external pressures, thereby affecting subsequent culture, while ensuring that the hose is sealed and connected to each inlet and outlet.

Preferably, the water inlet and outlet holes on the outside of the tank body are respectively distributed on the upper edge and the bottom of the outside of the tank body, and are connected to the water inlet and outlet pipes of the side wall. Under the action of gravity, the water sample can flow out more easily to prevent the water flow from causing a large impact on the double-sided culture medium, causing edge leakage and affecting the growth of microorganisms; each in situ culture tank has only one water inlet and outlet hole, which are respectively connected to the external water circulation device and the water storage device.

Preferably, the tank body has multiple water inlet holes and water outlet holes, which are evenly distributed on the inner side of the side wall water flow channel from top to bottom, communicate with the water flow channel, and are respectively connected to the water inlet valve and water outlet valve of the double-sided culture dish replaceable sealing plug.

Preferably, the screws are located at the top of the water inlet pipe and the water outlet pipe respectively. This detachable sealing method facilitates regular cleaning of the water flow channel to avoid blockage.

The following beneficial effects can be obtained through the above technical solution:

1. Through the support net in the middle of the dish, after the culture medium solidifies, the solid culture medium can be fixed in the middle of the dish. After the sealed plugging inner cover at the bottom is removed, the upper and lower sides of the culture medium can be used for separation, cultivation and technical operations of microorganisms;

2. Through the aperture of the support net in the middle of the dish, the microbial strains growing on the upper and lower sides of the culture medium can achieve the exchange of metabolites and information, imitate the interaction phenomenon between microorganisms in nature, and explore the interaction mechanism between strains;

3. Through the support of the support net in the middle of the dish, different types or components of culture medium can be made on both sides according to the physiological and biochemical characteristics of the strains cultured on the upper and lower sides or the different research purposes, so as to coordinate the nutritional differences between different strains or achieve different research purposes;

4. When using growth-promoting strains to separate uncultured microorganisms in nature, the growth-promoting strains can be separated from the strains to be separated to avoid contamination and facilitate subsequent separate cultivation and separation and purification;

5. By culturing on both sides of the culture medium simultaneously, it is possible to culture, separate and study two or more co-growth combinations;

6. The upper and lower lids and the bottom plug of the device are detachable structures, making the device easy to operate, low cost, highly repeatable and easy to popularize;

7. Through the cultivation on the upper and lower sides, the changes in the physiological metabolic functions of the growth-promoting strains caused by embedding are avoided, making the growth-promoting phenomenon more obvious and easier to observe;

8. Because the device is thicker than traditional culture dishes, it is more likely to slip when stacked, causing the device to break and affecting the accuracy of the internal samples. The anti-slip rubber rings on the outer surfaces of the upper and lower dish covers can increase the friction between the upper and lower culture dishes and reduce the occurrence of slipping;

9. After the double-sided solid culture medium is prepared, the water loss rate is faster than that of the traditional culture dish. As the culture time increases, the internal water is lost, which easily causes the surface of the culture medium to crack. The water storage strip on the inner surface of the dish cover and the rubber strip on the outer side of the side wall can reduce the water loss rate of the culture medium and prolong the cracking time of the culture medium.

10. Because growth-dependent strains are dependent on growth-promoting bacteria, the detachable photocopy plate in the device can directly transfer the colonies of the entire culture medium to a new culture medium. Combined with the positioning effect of the grid lines, it is easier to screen and separate the growth-dependent strains to be separated, greatly reducing the workload of separation and purification;

11. Microbial strains have various nutritional types. In an aerobic environment, the dish cover and the dish body are connected by an outer rubber strip to ensure ventilation while maintaining internal humidity and avoiding cracking of the culture medium surface. In an anaerobic environment, the dish cover and the dish body are connected by a sealing rubber strip to facilitate anaerobic culture and the transfer of anaerobic bacteria. The two connection designs enhance the application scope of the device.

12. Because it is impossible to determine which physical and chemical factors or biological factors play a decisive role in the growth of specific microbial groups, many groups often cannot be cultured under laboratory conditions. Through this device, some environmental or biological samples, such as water samples, sediments, soil, animal and plant tissues, etc., can be placed on the culture medium surface in the lower half of the dish body, and fixed or sealed with a plugging inner cover. In combination with an in-situ culture tank, in-situ culture or co-culture can be achieved. When inverted culture is performed, unknown physical and chemical factors or biological metabolites in the sample can penetrate through the culture medium to the other side, which not only makes up for the gap in environmental factors, but also facilitates the separation and culture of microorganisms on the other side.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the combined structure of a double-sided culture dish and a detachable photocopy plate of a multifunctional microorganism screening and culture system of the present invention;

FIG2 is a partial top view of a double-sided culture dish body in the present invention;

FIG3 is a top view of a photocopy plate in a detachable photocopy plate of the present invention;

FIG4 is a structural diagram of a support frame in a detachable photocopy plate of the present invention;

FIG5 is a schematic diagram of the structure of a notched dish cover C in the present invention;

FIG6 is a schematic diagram of the structure of an in-situ culture tank in the present invention;

FIG7 is a schematic diagram of the use of the in-situ culture tank in the present invention;

FIG8 is a schematic diagram of a breathable double-sided culture dish according to the present invention;

FIG9 is a schematic diagram of a sealed double-sided culture dish according to the present invention;

10 is a schematic diagram of a double-sided culture dish with a notched dish C cover according to the present invention;

11 is a schematic diagram of the blocking inner cover structure of the present invention;

FIG12 is an enlarged schematic diagram of the structure at position E of the present invention;

FIG13 is an enlarged schematic diagram of the structure at position F of the present invention;

14 is an appearance diagram of the photocopy plate sterilization box of the present invention;

Among them: anti-slip rubber ring-1; water storage bar-2; dish cover A-3; button-4; handle-5; support foot-6; copy plate-7; positioning hole-8; magnetic head-9; side wall-11; limit strip-12; sealing outer rubber strip-13; breathable outer rubber strip-14; support net-15; fixing module-16; anti-seepage strip-17; ruler-18; breathable sealing inner cover-19; sealing strip-20; sealing inner cover-21; replacement inner cover-22; one-way water stop valve-23; dish cover B-24; dish cover C-25; telescopic rod-26; spring-27; threaded hole-28; notch-29; handle-30; vent valve-31; buckle-32; outer water inlet hole-33; outer water outlet hole-34; screw-35; culture dish holder-36; water inlet pipe-37; water outlet pipe-38; inner water inlet hole-39; inner water outlet hole-40; hose-41; tank body-42; sealing cover-43; ventilation hole-44; slot-45; disassembly tongue-46; slot-47; slot-48; photocopy plate sterilization box-49.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings:

As shown in Figure 1-14, a multifunctional microbial screening and culture system includes a double-sided culture dish, a detachable photocopy plate and an in-situ culture tank, wherein the double-sided culture dish is prepared by an integrated double-sided solid culture medium in the form of an embedded support mesh, and double-sided culture and in-situ culture of microbial strains are achieved under aerobic and anaerobic conditions; the detachable photocopy plate is used in conjunction with the double-sided culture dish to quickly screen out microbial strains with interactive functions; the in-situ culture tank is mainly used for the in-situ culture of liquid samples under laboratory conditions, and can be used for the separation and purification of aerobic and anaerobic bacteria.

The double-sided culture dish includes a culture dish body and a dish cover. The dish body is a cylindrical hollow structure. The top and bottom of the dish body are open. It is composed of a side wall 11, a limit strip 12, an outer rubber strip, a support net 15, a fixing module 16, an anti-seepage strip 17, a ruler 18 and a blocking inner cover. The side wall 11 is fixedly connected to the support net 15 through the fixing module 16. The limit strip 12, the anti-seepage strip 17, and the ruler 18 are all located on the inner side of the side wall, and the limit strip 12, the anti-seepage strip 17, and the ruler 18 are distributed on both sides of the support net 15.

The limit strip 12 is used to limit the position of the photocopy plate 7. The serial number next to the limit strip 12 corresponds one-to-one with the positioning holes on the photocopy plate 7, so that the positions of the growing colonies on the two solid culture medium surfaces before and after photocopying are consistent. By comparing the growth of the colonies before and after photocopying, the interaction of the strains on the two sides of the culture medium can be determined.

The outer rubber strips are divided into a sealing outer rubber strip 13 and a breathable outer rubber strip 14, both of which are connected to the side wall 11 through a slot 45 in the middle of the outer side wall; the sealing outer rubber strip 13 is an H-shaped rubber strip, which can be sealed and connected to the dish cover A3 and the dish cover B24 through two upper and lower slots to block the gas exchange between the inside and outside of the dish body, and facilitate the transfer of obligate anaerobic bacteria after cultivation in an anaerobic environment; the breathable outer rubber strip 14 is provided with ventilation holes 44 to ensure the gas exchange between the inside and outside of the double-sided culture dish while controlling the loss rate of water in the internal culture medium to avoid cracking on the surface of the culture medium.

The mesh density of the support net 15 will have different effects on the cracking of the double-sided solid culture medium surface. When the culture medium agar concentration is 2%, the mesh aperture must be greater than 2mm and less than 15mm. When the culture medium agar concentration increases, the minimum and maximum values of the mesh aperture will increase, but when the culture medium agar concentration decreases, the minimum and maximum values of the mesh aperture will decrease; when the detachable photocopy plate is used for colony photocopy transfer, the culture medium agar concentration should be higher than 1%; when the in-situ culture tank is used for in-situ culture, the agar concentration can be increased to about 4%, which can increase the pressure bearing capacity of the double-sided solid culture medium, improve the sealing degree between the culture medium and the side wall 11, and prevent leakage; in order to prevent bubbles from remaining inside the double-sided solid culture medium during the preparation process and to make the edges more tightly closed, the culture medium temperature should not be cooled too low when pouring, and it should not be shaken before pouring.

The anti-seepage strip 17 is annular and sealed with the side wall 11 and fixed between the support net 15 and the inner surface of the sealing plug. The solid culture medium can be embedded inside after solidification, and together with the fixing module 16, prevent the liquid from penetrating from the gap between the solid culture medium and the side wall 11 to the other side of the culture medium.

The scale 18 is located on the same side as the anti-seepage strip 17, extending from the support net 15 to the edge of the lower opening of the dish body, and is used to indicate the thickness of the culture medium and help select a sealing inner cover of appropriate thickness.

The blocking inner cover includes a breathable blocking inner cover 19, a sealed blocking inner cover 21, and a replaceable blocking inner cover 22, all of which are sealed and connected to the side wall 11 through a card groove G on the edge, and have a disassembly tongue 46 on the outer side to facilitate the installation and disassembly of the blocking inner cover; the inner diameter d of the blocking inner cover is the same as the inner diameter of the lower part of the dish body, and the outer diameter D of the blocking inner cover is smaller than the inner diameter of the dish cover B24 and the dish cover C25; the height H of the blocking inner cover is smaller than the height h of the dish cover 24 and the dish cover 25.

When preparing the culture medium, according to the required thickness of the culture medium, a sealed inner cover 21 of appropriate specifications is selected to seal the lower space of the dish body, and the culture medium that has not yet solidified is poured into the dish body from the upper part of the dish body. After solidification, the culture medium is embedded in the support net 15 and the waterproof strip 17 to form a double-sided solid culture medium, thereby realizing the cultivation of microorganisms on both the upper and lower surfaces at the same time.

When in situ culture is carried out, after the double-sided solid culture medium is prepared, the double-sided culture dish is inverted, the dish cover B24 is opened, and non-liquid samples such as soil, plant tissue, sediment, etc. are placed in it. The sample is sealed with a breathable inner cover 19 to ensure that the sample does not fall when the microbial strain on the other side is operated during the culture process. It is convenient to add moisture to the sample surface during the culture process so that the components in the sample can penetrate into the culture medium. At the same time, gas is allowed to pass through to avoid adverse effects of lack of oxygen on the sample.

Example 1: When performing in situ culture, after the double-sided solid culture medium is prepared, the double-sided culture dish is inverted, the dish cover B24 is opened, and after a liquid or a sample with a high water content is placed in it, it is sealed with a sealed inner cover 21 to prevent sample leakage when performing microbial operations on the other side.

Example 2: When in situ culture is carried out, after the double-sided solid culture medium is prepared, the double-sided culture dish is inverted, the dish cover B24 is opened, and the sample is placed. When the water sample needs to be replaced regularly, it is sealed with the replacement-type sealing inner cover 22, and the dish cover B24 is replaced with the dish cover C25. The in situ culture tank is used to simulate the natural environment to the maximum extent to separate and culture microorganisms.

The dish cover is composed of a dish cover A3, a dish cover B24 and a dish cover C25. The dish cover A3 is located at the upper port of the dish body, and the dish cover B24 and the dish cover C25 are located at the lower port of the dish body. They are all connected to the side wall 11 through an outer rubber strip. When there is no need to cooperate with the in-situ culture tank for sample replacement, the dish cover A3 and the dish cover B24 are used. If it is necessary to replace the sample inside the double-sided culture dish, the dish cover A3 and the dish cover C25 are used. The side wall of the dish cover C25 has a notch 29 to facilitate the passage of the hose 41. When the dish is inverted for culture, the dish cover C25 is on top to play a supporting role.

The detachable photocopy plate comprises a button 4, a handle 5, a supporting foot 6, a photocopy plate 7, a positioning hole 8, a magnetic head 9 and a photocopy plate sterilization box 49. When in use, multiple photocopy plates 7 are placed in the photocopy plate sterilization box 49 for sterilization. After sterilization, the magnetic head 9 is connected to the supporting foot 6. The handle 5 is held to align the photocopy plate positioning hole 8 with the limit strip 12 for photocopy inoculation of the colony. The handle 5 is pressed to replace the photocopy plate 7 for large-scale screening and cultivation.

The in-situ culture tank comprises a handle 30, a vent valve 31, a buckle 32, an outer water inlet hole 33, an outer water outlet hole 34, a screw 35, a culture dish support 36, a water inlet pipe 37, a water outlet pipe 38, a hose 41, a tank body 42 and a sealing cover 43, wherein the hose 41 is sealed and connected to each interface; when in-situ culture is carried out under aerobic conditions, the double-sided solid culture medium is prepared, the dish cover A3 is buckled, the dish is inverted and then a sample is added, the dish body of the double-sided culture dish is blocked with a replacement type blocking inner cover 22, the hose 41 is connected to the one-way water stop valve 23 on the replacement type blocking inner cover 22, the dish cover C25 is buckled, and the double-sided culture dish is stacked and placed in the in-situ culture tank for culture. The dish holder 36 is put into the tank body 42, and then the hose 41 is connected to the water inlet hole 39 and the water outlet hole 40 in the tank body 42, the screws 35 are used to seal the top of the water inlet pipe 37 and the water outlet pipe 38, and the sealing cover 43 is used to seal the tank body 42 through the buckle 32, the ventilation valve 31 is closed, and the outer water inlet hole 33 and the outer water outlet hole 34 are respectively connected to the water pump and the water storage device through the hose 41, and placed in a suitable environment for the cultivation of microorganisms; when the in-situ culture is carried out under anaerobic conditions, except that the anaerobic bag is added into the tank body 42 before the sealing cover 43 is used to close the tank body 42, the other operations are similar to the in-situ culture under aerobic conditions.

The above are all preferred embodiments of the present invention. For ordinary technicians in this technical field, without departing from the principle of the present invention, various equivalent modifications to the present invention belong to the protection scope of the claims attached to this application.

Claims (10)

1. A multifunctional microorganism screening and cultivation system, characterized in that: the cultivation system consists of a double-sided culture dish, a detachable photocopy plate and an in-situ cultivation tank; The double-sided culture dish is composed of a dish body, a blocking inner cover, and a dish cover; the dish body is composed of an outer rubber strip, a side wall, a fixing module, a support net, a limiting column, and a waterproof strip; the outer rubber strip is arranged at the middle position outside the side wall; the support net is fixed to the middle position inside the dish body through the fixing module and is sealed with the side wall; the limiting column is located in the upper inner half of the side wall; the waterproof strip is located near the support net in the lower inner half of the side wall; the blocking inner cover is located in the lower half of the dish body; the upper and lower dish covers are respectively located at the upper and lower positions of the dish body, connected to the dish body through the outer rubber strip, the outer surface of the dish cover is provided with a circle of anti-slip rubber ring, and the inner surface of the dish cover is provided with a circle of water storage strip; The detachable photocopy plate is placed on the upper part of the dish body, and is composed of a handle, a supporting foot and a photocopy plate. There are positioning holes on the edge of the photocopy plate, and the positioning holes are arranged correspondingly to the limiting strips. The in-situ culture tank is composed of a sealing cover, a tank body and a culture dish holder. A water inlet pipe and a water outlet pipe are arranged on the side of the tank body. An outer water inlet hole is arranged on the outer side of the water inlet pipe, a water inlet hole is arranged on the inner side of the water inlet pipe, an outer water outlet hole is arranged on the outer side of the water outlet pipe, and a water inlet hole is arranged on the inner side of the water outlet pipe. The double-sided culture is placed on the culture dish holder. 2. A multifunctional microorganism screening and cultivation system according to claim 1, characterized in that: the outer rubber strip is divided into a sealing rubber strip and a breathable rubber strip, and the breathable rubber strip has some ventilation holes, which can enable gas exchange inside and outside the device and control the loss rate of water in the internal culture medium. 3. A multifunctional microorganism screening and cultivation system according to claim 1, characterized in that: the plugging inner cover is truncated cone-shaped, and the inner diameter is the same as the inner diameter of the dish body, and is divided into three types: sealed plugging inner cover, breathable plugging inner cover and replaceable plugging inner cover; The inner surface of the sealed plugging inner cover is smooth, and the inner surface of the breathable plugging inner cover is made of a support frame, a bacterial filter membrane or filter paper material; the outer surface of the replacement type plugging inner cover has two one-way water stop valves, which can be connected to an external circulation device to allow liquid samples to flow in from one side and out from the other side, and is used for in situ culture; the three types of plugging inner covers are sealed and connected to the dish body through the edge grooves, and there are sealing patterns in the grooves to prevent leakage. 4. A multifunctional microorganism screening and cultivation system according to claim 1, characterized in that: the dish body and the dish cover are both made of transparent materials that can be sterilized at high temperatures, including but not limited to PC plastic, PP plastic and glass, the material of the fixed module is made of rubber, silicone, and plastic, and the anti-slip rubber ring on the outer surface of the dish cover is made of silicone or rubber high-temperature resistant and anti-slip material. 5. A multifunctional microorganism screening and culture system according to claim 1, characterized in that: the dish cover B is divided into two types, with and without a notch. The dish cover with a notch is used in conjunction with the in-situ culture tank, and the side notch facilitates the connection of the water pipe to the replacement-type plugging inner cover and the water inlet and outlet inside the in-situ culture tank. At the same time, its height is slightly higher than that of the dish cover A, and it is inverted on the upper part of the double-sided culture dish to play a supporting role, so that multiple double-sided culture dishes can be stacked in the in-situ culture tank; the dish cover B without a notch has the same structure as the dish cover A, and is used during co-culture and partial in-situ culture. 6. A multifunctional microorganism screening and cultivation system according to claim 1 is characterized in that: the detachable photocopy plate has five supporting feet, and there is a magnetic material at the top of the supporting feet. The telescopic rod in the middle is retractable, and its bottom end is kept horizontal with the other four supporting feet in a static state, so that when photocopying the bacterial colonies on the surface of the culture medium, the photocopy plate can be evenly stressed; the handle is connected to the supporting feet by a screw hole, which is convenient for replacement when the supporting feet are damaged; the support frame can be separated from the photocopy plate by pressing a button, which is convenient for replacing the photocopy plate. 7. A multifunctional microorganism screening and cultivation system according to claim 1 or 6, characterized in that: the diameter of the photocopy plate is the same as the inner diameter of the dish body, and is divided into an upper and lower surface. There are five slots on the edge of the upper surface, and the slots contain magnetic materials that are adsorbed and connected to the support feet. The lower surface is a material that adheres to the bacteria. 8. A multifunctional microorganism screening and cultivation system according to claim 1, characterized in that: the sealing cover is sealed and connected to the tank body in a snap-fit manner, and there is a vent valve on the sealing cover, which can not only seal the in-situ culture tank to achieve anaerobic culture, but also connect the inside and outside for aerobic culture. 9. A multifunctional microorganism screening and cultivation system according to claim 1, characterized in that: the water inlet and outlet holes on the outside of the tank body are respectively distributed on the upper edge and the bottom of the outside of the tank body, and are connected to the inlet and outlet pipes of the side wall; each in-situ culture tank has only one water inlet and outlet hole, which are respectively connected to the external water circulation device and the water storage device, and the number of water inlet and outlet holes inside the tank body is at least two, which are evenly distributed on the inner side of the side wall water flow channel from top to bottom, and are connected to the water flow channel, and are respectively connected to the inlet valve and the outlet valve of the double-sided culture dish replacement type sealing plug, and the screws are respectively located at the top of the inlet pipe and the outlet pipe. 10. A multifunctional microorganism screening and cultivation system according to claim 1, characterized in that: on the inner surface of the upper part of the side wall, the horizontal and vertical grids corresponding to the support net are numbered to facilitate the positioning of the colonies on the surface of the culture medium.