Grantee Research Project Results

2024 Progress Report: Natural approach in antifouling protection: remedy for safer water for fisherman, boaters, and cargo ships

EPA Grant Number: SU840585
Title: Natural approach in antifouling protection: remedy for safer water for fisherman, boaters, and cargo ships
Investigators: Volkis, Victoria V
Institution: University of Maryland Eastern Shore
EPA Project Officer: Cunniff, Sydney
Phase: I
Project Period: August 1, 2023 through May 13, 2025
Project Period Covered by this Report: August 1, 2023 through July 31,2024
Project Amount: $24,958
RFA: 19th Annual P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet Request for Applications (RFA) (2022) RFA Text |  Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Sustainable and Healthy Communities

Objective:

Objectives:

1)   To build a pilot aquarium for long-term testing of new antifouling formulations on different types of submerged surfaces.

2)   To demonstrate effectiveness and conduct a pilot study of the concept of the use of natural extracts encapsulated into biocompatible polymers for antifouling protection of submerged surfaces.

3)   To evaluate in long-term experiments how water type and parameters, as well as the type of plant materials, polymers, and solvents, influence the ability of the coating to protect against biofouling.

 

The University of Maryland Eastern Shore (UMES) is an 1890 land grant historically black college and university (HBCU) located on the rural Delmarva Peninsula, home to over 12,000 small farms and fishery businesses. The project aims to address the economically costly and environmentally concerning problem of biofouling, the formation of biofilm on submerged surfaces, faced by cargo and military ships, fisheries, and recreational boats, as well as some industries such as petroleum mining, water pipe systems, National Aeronautics and Space Administration (NASA) projects, and even dentistry. Along with rural communities of fishermen and recreational boaters, this project indirectly benefits small farmers, creating new markets for their medical herbs and specialty super fruits. Additionally, the project contributes to the environmental health of marine environments by reducing the transmission of biofilm-generating bacteria by boats and ships beyond their natural habitat to areas where it is invasive, causes uncontrolled algae bloom, and contribute to fish and crab mortality.

 

Based on preliminary positive results obtained in Navy-funded research, this proposed research screens different super fruits and medical herbs as antifouling agents and develops pilot devices to demonstrate our proof of concept of antifouling coatings in long-term experiments. Our testing platform is a demonstration aquarium equipped with water pumps, aerators, water quality sensors, and 3D-printed models of boats and platforms having submerged testing surfaces. Aquarium water is collected using UMES sampling boats in Assawoman Bay and local rivers and ponds.

 

In such a way, our challenge is to demonstrate the efficacy of natural extract formulations in antifouling protection using a custom-model aquarium.

 

The intellectual merit of the project is to advance knowledge and understanding within and across the role of phytochemicals of natural extracts in biofouling in long-term experiments using the model aquarium pilot, increasing the understanding of natural, environmentally friendly, and non- toxic solutions for biofilm prevention for boats, ships, submerged surfaces, pipes, autonomic water systems, and others, that will directly benefit communities of fishermen and rural small farmers. Graduate and undergraduate students from underrepresented minorities are involved in the research project, enhancing their preparation for scientific careers in science, technology, engineering, and math (STEM). The education, training, mentoring, and professional development for students, along with new capabilities for faculty, is strengthening the STEM disciplines at UMES, Maryland’s 1890 HBCU.

 

The broader impact includes antifouling solutions that, in the future, may also be used outside of the field of marine environments, such as dentistry, water pipe technology, and international space station water purification. The fundamental correlations found with the selective representation of plants can be applied to predict plants of interest better. This project creates new collaborations at UMES between our chemistry, biology, and engineering faculty. Local rural farmer communities will benefit from potentially new fields of application for produce from their farms, helping to sustain those communities. Local fishery and recreational boater communities will benefit from reduced expenses for their businesses and hobbies and the availability of healthier, nontoxic materials for their boats.

 

The project “input” includes an interdisciplinary team of faculty, graduate, and undergraduate students specializing in chemistry, phytochemistry, instrumental analysis, physics, technology, microbiology, and environmental science. The laboratory is equipped with organic synthetic glassware, spin coaters, optical and phase contrast microscopes, 3D Printers, atomic force microscopy (AFM), and modern instrumentation such as nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), ultraviolent-visible (UV/Vis) spectrometers, high-performance liquid chromatography (HPLC), gas chromatography mass spectrometry (GCMS), liquid chromatography mass spectrometry (LCMS), gravimetric analysis mass spectrometry (IGA/MS), differential scanning calorimetry (DSC), access to modern library and computing including professional software such as Spartan 10 and ChemOffice suite, support of an administrative assistant, department chair, librarian, mechanical and electronic shops and more.

 

The Project outcomes are:

1)             Results of the first round of long-term antifouling tests lasting three weeks, two months, and four months, with three plant materials. Full characterization of extracts from these plants, coating formulation, surface analysis before and after the test, and influence of sweet vs. salt water.

2)             Scientific findings presented in June 2024 at the 2024 EPA P3 National Design Expo and published in a peer-reviewed journal, as well as presented at conferences.

3)             Project results incorporated into undergraduate capstone experience courses of CHEM 498 and CHEM 499.

4)             The report and application for Phase II funding.

 

Additional outputs include building more interdisciplinary collaborations among faculty at UMES (Volkis, Weaver from UMES and Den-Ouden and Ristvey from collaborating UMES and UMD extensions), training underrepresented science students in the P3 and environmental justice approaches, and strengthening collaboration with local farmers and boater communities.

Progress Summary:

Progress to Date:

During phase I of the project, we proved our concept successfully. We developed non-toxic antifouling formulations and proved that the protection effect comes from the plant extract, not from the polymer or solvent used in the formulation. We were able to build test systems for longer tests, lasting between three weeks and four months.

 

We were able to pick the three most potent plants to work with for longer experiments by performing phytochemical characterization of the extract and three weeks of tests. We were able to run the first series of such experiences lasting up to four months. For these experiments, three different experiment-modeling aquariums were designed and built.

 

A)             Technical aspects of the project--both negative and positive. We built three different setups for long-term tests: (1) Shaker type of setup for up to three weeks long tests. We have analyzed how water parameters change with time for samples of water collected at different local sources. We found that significant changes in both water parameters and bacterial quota started after three weeks. As a result, three-week experiments do not require building special devices with a function to keep water at the same parameters. Our shaker-type model includes special holders for glass and metal microscopic slides. A series of stackable containers filled with sweet and salt water and water stained by methylene blue or fluoresceine (stain bacteria in water and allow to follow how bacteria precipitates and grows inside biofilms) with slides holders with samples inside are placed on the strong orbital shaker that makes slow motions imitating waves for three weeks. Then, microscopic and gravimetric analyses are performed and compared for protected vs. unprotected slides and controls. (2) Long-term aquariums for sweet water, and (3) long-term aquariums for salt water. Systems (2) and (3) consist of a core element - a 36-gallon rectangular glass aquarium outfitted with standard equipment to create a sustainable aquatic environment. This environment serves as the platform for introducing biofouling organisms and subsequently testing the effectiveness of various control methods in 2-4 months tests. 3D-printed sample holders were designed as submerged "boats" and printed using polylactic acid (PLA). These boats are configured to hold glass and metal substrate slides coated with anti-biofouling formulations. The 75mm x 25mm x 1mm slides are inserted into designated slots on the sides of the boats, ensuring they remain submerged within the aquarium water. Two identical boats are deployed within the aquarium using a motorized suspension system in each of the four lanes. Each boat is secured to a belt driven by a stepper motor. An Arduino UNO microcontroller equipped with a CNC Shield expansion board controls the stepper motor, allowing for precise positioning and movement of the sample holders within the aquarium.

Our three-week tests with the three best plants proved the concept and showed promising results. We have performed experiments with different concentrations of extract and the control that only had polymer but not an encapsulated extract. By increasing the extract concentration, we have shown that the amount of biofilm has significantly decreased for all three plants. While conducting long-term tests, we found that the fifth stage of biofilm formation- detachment of part of biofilm precipitate along with bacteria in it- starts already in the second month of the experiment. This negatively affects gravimetric analysis. To resolve the issue, we had to change the experimental design, and instead of running the experiments for a whole 2 or 4 months, we now run it with stops every two weeks for drying and weighing to find the exact time and extent of the detachment. These new experiments are in progress now and will be published by the end of the no-cost extension.

 

Additionally, we have performed a full phytochemical characterization of all extracts involved in this project.

B)            Technical effectiveness and economic feasibility of the methods and techniques. Our solution is not only effective but also environmentally friendly and not expensive. The formulation includes polymethyl methacrylate (PMMA), the polymer that is already used by the paint industry and, therefore, would be the easiest for technology transfer of our findings. This polymer is biocompatible. Plants are renewable and not expensive to grow. The coating technology is yet to be developed. In laboratory conditions, we use a spin coating. This is an easy technique but is not suitable for industrial coating. Current thermo-spray technologies available in the industry would need modification to reduce the temperature because temperatures higher than 75 degrees Celsius would cause decomposition of antioxidants and evaporation of some essential oils. Further development will be focused on simplification of formulations and adapting the coting process.

C)             Contribution to the solution of environmental problems. Biofilm causes tremendous economic and environmental damage - corrosion, extra fuel consumption, decreased boat performance, expensive cleaning of all submerged objects, and significant ecological damage. It directly affects rural communities of fishermen and recreational boaters and indirectly benefits small farmers, creating new markets for their medical herbs and specialty super fruits. The project contributes to the environmental health of marine environments by reducing the transmission of biofilm-generated bacteria by boats and ships beyond their natural habitat to areas where it is invasive. Our solution is totally biocompatible.

Future Activities:

Our concept-proving experiments have shown several steps that need further investigation before the project is ready for technology transfer. First, we need to investigate the possibility of working with synthetic antioxidants and essential oils that are identical to those found in our best plants yet commercially available. This will not only simplify technology and eliminate dependence on farming but will also allow for a significant increase in the concentration of active components in the formulations. Second, we need to develop or adopt one of the industrially acceptable coating technology. We will need to either focus on low-temperature processes or work with individual antioxidants and essential oils that are thermally more stable and allow coating at high temperatures. Another feasible direction is to try and expand the scope of used polymers – from currently used PMMA, which is biocompatible but not biodegradable, to polycyclic esters that are also biodegradable and would slowly decompose in naturally acidic ocean water to water and carbon dioxide and slow-release the active ingredient of the extract, similarly, to slow release of medications in the pharmaceutical industry. This would prolong the period between the re- coatings of ships. Finally, we need to investigate the process and mechanism of biofilm growth in real time. For this purpose, a custom-designed Open-Source Quartz Crystal Microbalance Platform should be engineered and used.

 

Proposed Phase II Objectives and Strategies:

Based on the conclusions above, we propose for phase 2:

·       Short- and long-term antifouling experiments with individual antioxidants and essential oils found in our best pants, such as (but not limited to) quercetin, gallic acid, eugenol, borneol, rosemaric acid, gingerol, and more.

·       Experiments with biodegradable polymers as a replacement for PMMA – polylactide, polycaprolactone, and more.

·       Experiments with different coting techniques used in industry, such as spray coating, dip coating, brush/roll coating, and flow coating, and studying how these techniques affect the protection quality of the surface.

·       Study biofilm growth dynamics in real-time for protected and unprotected surfaces using a custom-designed Open-Source Quartz Crystal Microbalance Platform.

·       Performing experiments with real boats over the fishing season (for such, we have an agreement with some boaters from the Nanticoke Marina at Nanticoke, MD)

Journal Articles:

No journal articles submitted with this report: View all 11 publications for this project

Supplemental Keywords:

  biofouling, antifouling protection, natural extracts, biocompatible polymers, protective coating materials, boat protection, invasive bacteria in water, long-term tests