CN110669370B

CN110669370B - Application of beauvericin from marine fungi in preventing and removing marine fouling organisms

Info

Publication number: CN110669370B
Application number: CN201910992813.6A
Authority: CN
Inventors: 佘志刚; 蔡润林; 严涛; 曹文浩
Original assignee: South China Sea Institute of Oceanology of CAS; Sun Yat Sen University
Current assignee: South China Sea Institute of Oceanology of CAS; Sun Yat Sen University
Priority date: 2019-10-17
Filing date: 2019-10-17
Publication date: 2021-05-14
Anticipated expiration: 2039-10-17
Also published as: CN110669370A

Abstract

The invention discloses application of beauvericin derived from marine fungi in preventing and removing marine fouling organisms. The application of the beauvericin in preventing and removing marine fouling organisms is disclosed for the first time, the beauvericin has a remarkable inhibiting effect on the attachment of the marine fouling organisms on solids, and the beauvericin has a remarkable effect under the condition of low-content coating. Meanwhile, marine organisms are not killed when the marine organisms are inhibited from attaching, and the repellent effect is achieved. The compound is extracted from fermentation products of marine fungi, has reliable and stable sources, and has good application prospects in the prevention and removal of fouling organisms of various marine artificial facilities.

Description

Application of beauvericin from marine fungi in preventing and removing marine fouling organisms

Technical Field

The invention belongs to the field of marine antifouling paint, and particularly relates to application of beauvericin derived from marine fungi in prevention and removal of marine fouling organisms.

Background

In the historical process of developing and utilizing the ocean by human beings, biofouling is one of the major problems to be solved urgently in the industries of ocean transportation, ocean engineering, ocean fishery and the like. Marine biofouling refers to the phenomenon that marine microorganisms, plants or animals attach to ships or various artificial facilities immersed in seawater to adversely affect the economic activities of human beings, and the main harm is to increase the roughness and weight of the ships, thereby increasing the resistance, reducing the navigational speed, increasing the fuel consumption and the maintenance cost of the ship body; the normal work of various ocean facilities is hindered, and drifting, unbalance and even overturning are caused; in the aspect of marine aquaculture, the aquatic culture device can compete for attachment bases and baits with cultured shellfish or block net cages to cause unsmooth water flow and insufficient oxygen supply, thereby influencing the yield and quality of cultured aquatic products.

Currently, antifouling paints are most widely used in marine fouling organism control technologies and methods. The traditional antifouling paint, such as cuprous oxide, organic tin and the like, forms a poison concentration layer with toxic and killing effects on marine plant spores or marine animal larvae through releasing antifouling agents such as copper, mercury, tin, arsenic and the like in the paint, thereby achieving the antifouling purpose. However, due to teratogenic toxicity to marine organisms, organotin antifouling paints have been banned globally by the International Maritime Organization (IMO) from 2008/9/17. The copper oxide coating is listed in the product list of 'high pollution and high environmental risk' by the national environmental protection department of China, and is prohibited to be used in 2012. Therefore, the need for a nontoxic, environment-friendly and efficient alternative coating is urgently needed.

The competition of various species in the marine environment to the space is very violent, in order to avoid the possible harm caused by the attachment of other organisms, some organisms in the sea form a unique self-defense mechanism in the long-term evolution process, and the fouling and the attachment of other organisms can be prevented by generating secondary metabolites which are harmless to the environment and have antifouling activity, so that the marine environment is favorable for self survival. These natural antifouling compounds are a very desirable class of antifouling agents which achieve an antifouling effect by a repellent effect rather than a poisoning effect, which not only have excellent antifouling properties, but also do not cause environmental damage. Therefore, the method has important significance and value for searching novel, nontoxic, environment-friendly and efficient natural antifouling compounds from natural resources.

Beauverine is a hexamylopeptide fungal compound produced by a variety of fungi of the genus Fusarium, and many natural cyclic peptide compounds have defined biological activities. The literature (publication No. CN 101669939) discloses that a type of beauvericin is separated from marine-derived fungal metabolites, and reports strong drug-resistant tubercle bacillus resisting activity. However, at present, in the field of marine antifouling, no relevant report discloses the role of beauvericin in the prevention and control of fouling organisms.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides application of beauvericin which is derived from marine fungi and has good marine biofouling resisting activity in marine biofouling organism prevention and removal.

The invention realizes the aim through the following technical scheme:

the invention relates to application of beauvericin in preventing and removing marine fouling organisms, which has the chemical name of (3S,6R,9S,12R,15S,18R) -3,9,15-tribenzyl-6,12,18-triisopropyl-4,10, 16-trimethyl-1, 7, 13-triazine-4, 10, 16-triazacyclohexadecane-2, 5,8,11,14, 17-hexanone [ (3S,6R,9S,12R,15S,18R) -3,9,15-tribenzyl-6,12, 18-trisisoproyl-4, 10,16-trimethyl-1,7,13-trioxa-4,10,16-triazacycloocta decane-2,5,8,11,14,17-hexaone]The molecular formula is C₄₅H₅₇N₃O₉Molecular weight is 783, and the structural formula is as follows:

the beauvericin provided by the invention can be coated on a solid surface, so that the attachment of marine fouling organisms on the solid surface can be inhibited. However, the application to the solid surface is only one mode of applying the invention, and any application of the compound to preventing the attachment of marine fouling organisms belongs to the protection scope of the invention.

The coating amount of the beauvericin is 10 mu g/cm²In addition, the biological inhibitor has obvious inhibiting effect on the attachment of fouling organisms, can not kill marine organisms and has extremely low toxicity.

According to the invention, a large number of experiments show that the beauvericin has a good inhibition effect on the attachment of the tendrils. The marine fouling organisms comprise three major types of animals, plants and microorganisms, wherein the types which are harmful and difficult to remove after attachment are mainly organisms with calcareous shells, sessile stemmed leg (barnacles) living in campuses and bivalve mollusks (mussels and oysters) and the like. Among them, the stemless vine is represented by the reticulate barnacle. The balanus reticulatus is one of the main fouling organisms, is widely distributed in south China sea, and has absolute advantages in fouling organism communities. Therefore, the method has important representative significance in the verification test of the invention by selecting the balanus reticulatus as an experimental object.

Based on fouling organisms, the method can be generally divided into two life stages, namely a planktonic life stage from the development of larva out of an egg membrane to the intermittent exploration of the surface of an object to prepare for attachment and metamorphosis; the self-larvae are selected to settle at the positions, and after adhering to the surfaces of the self-larvae and being metamorphosed to form larvae, the larvae are in a fixed or adhering life stage. From a fouling point of view, the danger that fouling organisms pose to humans begins after their nutritional fixation or attachment life. If the settlement and metamorphosis of the larvae can be effectively inhibited, the purpose of preventing and removing fouling organisms can be achieved. Therefore, the method adopts the larvae of the balanus reticulatus as an experimental object to test the antifouling effect of the compound, and has scientific reasonability and representative significance.

The beauvericin of the present invention can be obtained by extraction from a fermentation product of marine fungi. The inventor obtains the beauvericin compound shown in the formula in an isocratic elution solution of petroleum ether/ethyl acetate (the volume ratio is 7/3) from an ethyl acetate extract concentrate of a fungus culture medium derived from mangrove through silica gel column chromatography.

Compared with the prior art, the invention has the following beneficial effects:

1. the beauvericin disclosed by the invention has a remarkable inhibiting effect on the attachment of marine fouling organisms on a solid, and when the surface of the solid is coated with a low content of the beauvericin, the beauvericin has an obvious effect of preventing the attachment of the marine fouling organisms.

2. The beauvericin disclosed by the invention does not contain heavy metal elements such as tin and copper and the like while effectively inhibiting the attachment of marine fouling organisms, is safe and non-toxic, does not kill marine organisms, plays a role in repelling, and has good social benefits from the aspect of environmental protection.

3. The beauvericin disclosed by the invention is a natural product, can be obtained by large-scale fermentation and extraction of fungi, has reliable and stable sources and large popularization and application potentials, and has good application prospects in prevention and removal of fouling organisms of various marine artificial facilities.

Detailed Description

The present invention is further explained with reference to the following examples, which are not intended to limit the scope of the present invention in any way.

Example 1

The beauvericin of the present invention can be separated from the thallus of mangrove-derived fungi. The method comprises the following specific steps:

fermenting and culturing mangrove endophytic fungi by adopting a rice culture medium, standing and culturing for 28 days, soaking a fermented product in ethyl acetate, concentrating an ethyl acetate crude extract by using a soaking solution under reduced pressure at the temperature of lower than 50 ℃, separating the ethyl acetate crude extract by using silica gel column chromatography, and obtaining the beauvericin compound shown in the formula in an isocratic elution solution of petroleum ether/ethyl acetate (the volume ratio is 7/3).

Example 2

The beauvericin of example 1 was subjected to an anti-biofouling activity experiment:

experimental groups A beauvericin compound was dissolved in methanol to prepare a solution with a concentration of 282.6. mu.g/mL. 1mL of this solution was added to a 6cm diameter dish and allowed to cover the bottom of the dish uniformly. After the solvent is completely volatilized, the content of beauvericin coated on the bottom of the culture dish is 10 mug/cm²。

Adding 1mL of methanol into the control group to uniformly distribute the solution at the bottom of the culture dish, and adding 10mL of seawater after the solvent is completely volatilized.

Only 10mL of seawater was added to the blank.

Each of the experimental, control and blank groups was provided with 3 replicates. 30 cyprids of balanus reticulates were added to each sample. Culturing in a constant temperature incubator at about 30 deg.C. The observation was performed every 24 hours. Statistical analysis of the final attachment and death status of each group of larvae was performed after 120 hours of culture.

Table 1 shows the attachment rate and mortality rate of cyprids of balanus reticulates in the experimental, control and blank groups. It can be seen that the attachment rate of larvae in the control group is 98.2% and that in the blank group is 98.1% after 120 hours of culture in the incubator, and there is no significant difference in the attachment rate of cyprids in the control group and the blank group (p)>0.05), indicating that methanol as a solvent does not leave harmful substances affecting the activity of the cyprids after volatilization, and is suitable for dissolving the compound. The attachment rate of the cyprids of the experimental group treated by the beauvericin compound is obviously lower than that of the control group, and the difference is obvious (p)<0.05), showing that beauvericin can effectively inhibit the attachment of cyprids of balanus reticulatus. In addition, the death rate of the cyprids in the experimental group, the control group and the blank group is 0, and the results of the three groups have no significant difference (p)>0.05), indicating that the beauvericin compound is present at a dose of 10. mu.g/cm²Has no toxic effect on cyprids of balanus reticulatus, does not kill marine organisms, and has anti-fouling activity on marine organismsThe beauvericin compound has a good application prospect in preventing and removing marine fouling organisms from the aspect of environmental protection.

TABLE 1 Beauverine anti-biofouling Activity results

Compound (I)	Percentage of adhesion%	The mortality rate is%
			Beauverine	11.2	0
Control group	98.2	0
			Blank group	98.1	0

Claims

1. Application of beauvericin derived from marine fungi in preventing and removing marine fouling organisms; the structural formula of beauvericin is shown as follows:

2. the use of claim 1, wherein: the beauvericin is applied to a solid surface.

3. Use according to claim 1 or 2, characterized in that: the coating amount of the beauvericin is 10 mu g/cm²。

4. Use according to claim 1 or 2, characterized in that: the marine fouling organism is reticulate barnacle.