Application of baicalin in preparation of marine antifouling composition
By using baicalin as the active ingredient in marine antifouling agents, combined with low-toxicity antifouling agents, an environmentally friendly coating was prepared, solving the ecotoxicity and failure problems of traditional antifouling agents and achieving a highly efficient, environmentally friendly, and economical marine antifouling effect.
Patent Information
- Application Number
- CN202511793301.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-01
- Publication Date
- 2026-02-27
AI Technical Summary
The use of heavy metals and organic compounds in existing marine antifouling agents leads to ecotoxicity and copper ion accumulation, affecting marine biosafety and human health. Furthermore, traditional antifouling agents suffer from initial release and subsequent failure.
Using baicalin as the active ingredient in marine antifouling compositions, combined with low-toxicity antifouling agents such as isothiazolinones and brominated pyrrolidones, environmentally friendly coatings, sprays, or impregnating agents are prepared by selectively inhibiting the secretion of byssal threads by large marine fouling organisms. Taking advantage of its excellent oleophilic and hydrophobic properties, it has good compatibility with base materials such as zinc acrylate resin, enabling controlled release.
It achieves the "zero pollution" goal of being free of heavy metal pollution such as copper, tin, and DDT. It is biodegradable, effectively inhibits the attachment of large marine fouling organisms, extends the coating's shelf life, reduces costs, meets international environmental standards, and has strong market adaptability.
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Figure CN121574584A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of marine antifouling materials technology, specifically relating to the use of baicalin in the preparation of marine antifouling compositions. Background Technology
[0002] The ocean is inextricably linked to human survival and development. Numerous human activities, including fishing, maritime transport, offshore oil and gas development, aquaculture, marine scientific research, and national defense, are highly dependent on the marine environment. However, the marine environment is complex and ever-changing, with factors such as temperature, salinity, current velocity, and sunlight all interacting. Among these factors, fouling organisms have a particularly significant and lasting impact on human marine economic activities. Large fouling organisms, such as barnacles, mussels, oysters, sea squirts, and polychaete tube worms, in particular, adhere firmly to the surfaces of various marine artificial facilities through byssal threads, gelatinous shells, or calcified exoskeletons. This results in a significant increase in the weight of these facilities and a sharp rise in surface roughness, leading to substantial additional costs and severe economic losses. For example, when fouling organisms cover nearly half of a ship's hull, navigation resistance increases dramatically, and fuel costs rise by nearly 80%, resulting in hundreds of billions of dollars in additional expenditures for the global shipping industry annually. Furthermore, fouling organisms can clog power plant cooling water pipes, subsea oil pipelines, and industrial cooling systems. These facilities are often located tens of meters or even deeper underwater, making cleaning or replacement extremely difficult and costly. In mariculture, large fouling organisms covering aquaculture cages and netting not only severely inhibit water flow and oxygen exchange and hinder feeding, but also significantly increase the weight of the nets, leading to structural fatigue. In more severe cases, this can cause localized hypoxia, disease outbreaks, and ultimately, large-scale mortality of farmed organisms and deterioration of the aquaculture environment. Therefore, developing truly environmentally friendly, efficient, and long-lasting marine antifouling technologies has become an urgent need to ensure the sustainable development of the marine economy and protect marine ecological security.
[0003] Antifouling coatings are currently the most widely used and cost-effective antifouling method globally. Their main mechanism of action involves the slow release of antifouling agents from the coating base, creating a concentration gradient on the material surface that inhibits or kills fouling organisms, thus preventing their adhesion and growth. However, for a long time, commercially available antifouling agents have generally used highly toxic heavy metal compounds or organic biocides to achieve this goal. The most typical examples are organotin compounds (such as tributyltin TBT) and cuprous oxide. The former was widely used from the 1960s and 70s to the 1990s, but due to its extremely high ecotoxicity (significant endocrine disruption, teratogenic, and lethal effects, and high accumulation in marine organisms), its use was completely banned by the International Maritime Organization (IMO) in 2008. Cuprous oxide, due to its broad-spectrum efficacy and relatively low price, still holds over 70% of the global marine antifouling coating market share. However, the continuous accumulation of copper ions in seawater and sediment has led to a year-on-year increase in copper concentration in nearshore waters, causing irreversible reproductive toxicity and genetic damage to marine organisms such as algae, shellfish, and fish, and causing long-term damage to the benthic community structure in coastal areas (especially ports and wharves). Furthermore, copper ions are amplified through the food chain, eventually accumulating in large quantities in fish, marine mammals, and even top predators, posing a potential threat to ecological security and human health. For these reasons, the EU, the US, Japan, and other countries have successively introduced strict regulations setting upper limits on the copper release rate of cuprous oxide-containing antifouling coatings and requiring a gradual reduction in their usage. Therefore, developing environmentally friendly marine antifouling coatings has become the most sought-after and strategically significant research direction and industrial upgrading direction in the international marine coatings field. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide the use of baicalin in the preparation of marine antifouling compositions.
[0005] The technical solution of the present invention is as follows:
[0006] Use of baicalin in the preparation of marine antifouling compositions for preventing the attachment of large marine fouling organisms.
[0007] The structural formula of baicalin is The molecular formula is C 21 H 18 O 11 , molecular weight 446.37.
[0008] In a preferred embodiment of the present invention, the active ingredients in the marine antifouling composition include baicalin and a complex antifouling component.
[0009] More preferably, the antifouling component is selected from at least one of isothiazolinone compounds, triazine compounds, N-2,4,6-trichlorophenylmaleimide, pyridine triphenylborane, bromopyrrolidone, and N-(fluorodichloromethyl sulfide)-phthalimide.
[0010] More preferably, the antifouling component is brominated pyrrolidone.
[0011] In a preferred embodiment of the present invention, the large marine fouling organism is the green mussel.
[0012] In a preferred embodiment of the invention, the marine antifouling composition is a coating, spraying agent, or impregnating agent.
[0013] More preferably, the marine antifouling composition is a coating, the raw materials of which include zinc acrylate resin, rosin, pigment, organobentonite, talc and organic solvent.
[0014] More preferably, the pigment is iron oxide red.
[0015] More preferably, the organic solvent is xylene.
[0016] More preferably, in the marine antifouling composition, the mass ratio of zinc acrylate resin, rosin, pigment, organobentonite, talc, baicalin, co-formulated antifouling components and organic solvent is 25-35: 10-15: 7-10: 1-3: 10-15: 10-20: 0-10: 15-20.
[0017] The beneficial effects of this invention are:
[0018] 1. The baicalin in this invention is derived from the dried root of Scutellaria baicalensis, a traditional Chinese medicine. It is a pure natural plant extract. When used as an active ingredient for marine antifouling, it is completely free of heavy metals such as copper, tin, and DDT, or persistent organic pollutants. It has no cumulative toxicity to marine water, sediment, and marine organisms. It is biodegraded rapidly and thoroughly, which can fundamentally eliminate the risks of bioaccumulation and food chain transmission caused by traditional antifouling agents, and truly achieve the goal of "zero pollution" in marine antifouling.
[0019] 2. The antifouling mechanism of baicalin in this invention against large marine fouling organisms is mainly through selective inhibition of byssal secretion, rather than the broad-spectrum toxicity of traditional antifouling agents. It exhibits highly efficient inhibition of target organisms while showing extremely low toxicity to non-target marine organisms, demonstrating high safety and meeting the highest environmental standards for novel antifouling agents under the International Maritime Organization (IMO) Convention on the Control of Hazardous Antifouling Systems on Ships and the EU REACH Regulation.
[0020] 3. The baicalin molecule in this invention contains multiple phenolic hydroxyl groups, which endow it with excellent oleophilic and hydrophobic properties. It is insoluble in seawater but readily soluble in commonly used organic solvents in coatings. It has excellent compatibility with self-polishing base materials such as zinc acrylate resin and rosin. Its release in the coating is stable and controllable, avoiding the problems of initial explosive release and late failure common in traditional antifouling agents. It can significantly extend the effective antifouling period of the coating, improve the utilization rate of active ingredients, and reduce the actual use cost.
[0021] 4. The baicalin in this invention can be used independently as a single effective antifouling ingredient to meet the demand for the most environmentally friendly products. It can also be flexibly compounded with other low-toxicity antifouling agents (such as isothiazolinones, brominated pyrrolidones, etc.). Through compound synergy, the antifouling spectrum can be further broadened and the ability to inhibit microfouling organisms can be improved. This allows the same technology platform to develop multiple series of products covering different price ranges, greatly enhancing market adaptability.
[0022] 5. The baicalin raw material in this invention is Scutellaria baicalensis, a traditional Chinese medicinal herb with an annual output of hundreds of thousands of tons. The resources are extremely abundant and stable, and the extraction process is mature (both water extraction and alcohol precipitation or macroporous resin method can achieve a purity of over 98%). The purchase price is much lower than that of mainstream imported antifouling agents such as Sea-Nine 211 and Econea, and the production cost can be reduced by 30%-50%. This is conducive to the rapid realization of large-scale industrialization and a significant reduction in maintenance costs for users of ships, offshore platforms, aquaculture facilities, etc. Attached Figure Description
[0023] Figure 1 This invention demonstrates the effect of scutellarin in Example 1 on byssal secretion and survival of jade mussels (**P<0.01).
[0024] Figure 2 This demonstrates the antifouling effect of the marine antifouling coating composition containing scutellarin in Example 2 of the present invention during marine testing.
[0025] Figure 3 This invention demonstrates the antifouling effect of the marine antifouling coating composition containing scutellarin and bromopyrrolidone in Example 3 of this invention during marine area testing. Detailed Implementation
[0026] The technical solution of the present invention will be further explained and described below with reference to specific embodiments and accompanying drawings.
[0027] Example 1: Detection of the inhibitory effect of scutellarin on the adhesion of jade mussels
[0028] Acquisition of Emerald Mussels: Adult Emerald Mussels are collected from the sea area and cultured overnight in an aerated room. Juvenile Emerald Mussels (shell length about 1 cm) with abundant byssal secretion are selected, and their byssal secretions are gently cut off. They are then cleaned and set aside for use.
[0029] Antifouling activity assay: Scutellaria baicalensis glycosides (purchased from Xi'an Linhe Biotechnology Co., Ltd., purity 90%) were dissolved in methanol. Experimental groups were set at 0, 1, 5, 10, 25, and 50 μg•mL. -1 A concentration gradient was used, with a control group consisting of membrane-filtered seawater (ck1) and a control group consisting of 1% methanol seawater solution (ck2). Each group had 10 replicates. A clean 24-well plate was used. 1980 μL of membrane-filtered seawater (filtered through a 0.22 µm membrane) was added to each well, followed by 20 μL of the prepared solution. One green mussel was gently placed into each well. After standing for 24 h, the green mussels were removed, and 3 mL of Coomassie brilliant blue staining solution was added for 1 h. The number of blue byssal discs in each well was observed and recorded, along with the mortality rate of the green mussels.
[0030] The inhibitory effect of baicalin on byssal secretion in *Mussel scutellariae* and its effect on the survival of *Mussel scutellariae* are shown in Figure 1. The calculated half-maximal inhibitory concentration (EC50) was 36.66 μg•mL. -1 The half-lethal concentration (LC50) is greater than 50 μg / mL. -1 This study confirmed that scutellarin has a good inhibitory effect on byssal secretion in jade mussels and has low toxicity.
[0031] Example 2: Detection of the antifouling effect of scutellarin in marine areas
[0032] In this embodiment, a marine antifouling coating composition is prepared, and the weight ratio of each raw material in its components is as follows:
[0033] 30 parts by weight of zinc acrylate resin
[0034] 12 parts by weight of rosin
[0035] Iron Red 8 parts by weight
[0036] 1 part by weight of organic bentonite
[0037] 13 parts by weight of talc
[0038] 20 parts by weight of scutellarin
[0039] 16 parts by weight of xylene
[0040] The specific preparation method includes the following steps:
[0041] (1) Add xylene to the container in proportion, start the high-speed disperser and stir at low speed (400 r / min).
[0042] (2) Slowly add rosin to the material obtained in step (1) and stir at low speed (400 r / min) until the rosin is completely dissolved. Then add zinc acrylate resin and continue stirring at low speed (400 r / min) until completely dissolved.
[0043] (3) Add organic bentonite, iron oxide red, talc powder and scutellarin to the material obtained in step (2) in sequence, increase the rotation speed to 1200 r / min, and stir for 10 min;
[0044] (4) Grind the material obtained in step (3) to a fineness of less than 60 μm using a basket mill. After testing the fineness and viscosity, the marine antifouling coating composition can be obtained.
[0045] The antifouling performance of the marine antifouling coating composition prepared in this embodiment is tested as follows:
[0046] The shallow-sea siding was tested in the Changjiang waters of Hainan, in accordance with the national standard GB / T 5370-2007. Figure 2 As shown, after 3 months of sea area plastering, the paint film was intact, with no peeling or blistering, and no obvious large-scale fouling organisms attached.
[0047] Example 3: Detection of the antifouling effect of scutellarin and bromoxypyrrolidone compound in marine areas
[0048] In this embodiment, a marine antifouling coating composition is prepared, and the weight ratio of each raw material in its components is as follows:
[0049] 30 parts by weight of zinc acrylate resin
[0050] 12 parts by weight of rosin
[0051] Iron Red 8 parts by weight
[0052] 1 part by weight of organic bentonite
[0053] 13 parts by weight of talc
[0054] 10 parts by weight of scutellarin
[0055] 10 parts by weight of bromopyrrolidinium
[0056] 16 parts by weight of xylene
[0057] The specific preparation method includes the following steps:
[0058] (1) Add xylene to the container in proportion, start the high-speed disperser, and stir at low speed (400 r / min);
[0059] (2) Slowly add rosin to the material obtained in step (1) and stir at low speed (400 r / min) until the rosin is completely dissolved. Then add zinc acrylate resin and continue stirring at low speed (400 r / min) until completely dissolved.
[0060] (3) Add organic bentonite, iron oxide red, talc, scutellarin and bromopyrrolidone to the material obtained in step (2) in sequence, increase the rotation speed to 1200 r / min, and stir for 10 min;
[0061] (4) Grind the material obtained in step (3) to a fineness of less than 60 μm using a basket mill. After testing the fineness and viscosity, the marine antifouling coating composition can be obtained.
[0062] The antifouling performance of the marine antifouling coating composition prepared in this embodiment is tested as follows:
[0063] The shallow-sea siding was tested in the Changjiang waters of Hainan, in accordance with the national standard GB / T 5370-2007. Figure 3 As shown, after 12 months of sea area plastering, the paint film was intact, with no peeling or blistering, and the coating surface was relatively clean with no obvious large-scale fouling organisms attached.
[0064] The above description is merely a preferred embodiment of the present invention, and therefore should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent and the contents of the specification should still fall within the scope of the present invention.
Claims
1. The use of baicalin in the preparation of marine antifouling compositions, characterized in that: This marine antifouling composition is used to prevent the attachment of large fouling organisms in the ocean.
2. The use as described in claim 1, characterized in that: The active ingredients in the marine antifouling composition include baicalin and synergistic antifouling components.
3. The use as described in claim 2, characterized in that: The antifouling component is selected from at least one of isothiazolinone compounds, triazine compounds, N-2,4,6-trichlorophenylmaleimide, pyridine triphenylborane, bromopyrrolidone, and N-(fluorodichloromethyl sulfide)-phthalimide.
4. The use as described in claim 3, characterized in that: The antifouling component is bromopyrrolidone.
5. The use as described in claim 1, characterized in that: The large marine fouling organism mentioned is the jade mussel.
6. The use as described in any one of claims 1 to 5, characterized in that: The marine antifouling composition is a coating, spraying agent, or impregnating agent.
7. The use as described in claim 6, characterized in that: The marine antifouling composition is a coating, the raw materials of which include zinc acrylate resin, rosin, pigment, organobentonite, talc and organic solvent.
8. The use as described in claim 7, characterized in that: The pigment is iron oxide red.
9. The use as described in claim 7, characterized in that: The organic solvent is xylene.
10. The use as described in any one of claims 6 to 9, characterized in that: In the marine antifouling composition, the mass ratio of zinc acrylate resin, rosin, pigment, organobentonite, talc, baicalin, co-formulated antifouling components, and organic solvent is 25-35: 10-15: 7-10: 1-3: 10-15: 10-20: 0-10: 15-20.