SINTEF Ocean explore different marine raw materials to find and describe new lipids and AMP (antimicrobial proteins) which will be further used for the antimicrobial bio-based platform for nanoformulation of QQE (quorum quenching enzymes). SINTEF Ocean produced several fractions and ingredients from different marine raw materials included fish (salmon) rest raw materials, seaweeds (Alaria Esculenta, Saccharina latisima), jellyfish (Aurelia aurita, Periphylla periphylla), gammarids. Drying, fractionation and hydrolysis are the technological solutions that were tested in the project. In collaboration with UPC (Spanish partners and project coordinator) several bioactivity evaluation rounds were performed. Fractions from Periphylla Periphylla showed the best antimicrobial properties, while hydrolysates from salmon bones were defined as ingredients with the best antioxidant potential. Further fractions from Periphylla Periphylla and hydrolysates from salmon bones as well as hydrolysates from gammarids were used for bioactivity screening. Fractions from Periphylla Periphylla and hydrolysates from gammarids were chosen for further work.
SINTEF Ocean also extracted lipids and peptides from different microalgae species for use in fish feed. Since the fatty acids fractions containing higher quantities of ethyl ester (EPA) and docosahexaenoic acid (DHA) have the best antimicrobial properties, SINTEF Ocean have grown different microalgae with a potential to produce high amounts of EPA or DHA. N. oceanica produced the highest amount of lipids, while the highest amount of polyunsaturated fatty acids was produced by C. vulgaris. The optimal condition (i.e., algae type/harvest stage) for producing the higher values of EPA and DHA were defined. SINTEF is planning to continuo the optimisation of condition to obtain both fatty acids at the same time for higher antibacterial effect and to improve the extraction efficacy.
NTNU in cooperation with Bar-Ilan Institute of Nanotechnology & Advanced Materials (Israel) tested efficiency of antifouling coated nets. NTNU received sections of aquaculture net pen that were coated with different concentrations of antifouling coating, and a control section that were uncoated. The coated and uncoated net pen sections were placed into a closed aquarium simulating the environmental conditions from our aquaculture farm. Biofilters enriched with microbiome from our sea-based farm were added into the aquarium as an initial test of antifouling properties and biotoxicity in a controlled environment. Biofilm formation and microbiome diversity was recorded weekly, for three months.
Results show that uncoated net pen had a normal biofilm formation and as expected the microbiome diversity were equal to the biofilter microbiome after three months. Biofilm started forming on the uncoated net after one week, and were growing on a weekly basis, both in microbiome richness and as visual biomass on the net.
The antifouling coated net came in two conditions, one with a high concentration of antifouling coating and one with a low concentration. The net with high concentration had a high biotoxicity and the microbiome on the biofilters and aquarium were almost completely killed in less than a week. After three months a minimal number of microorganisms were present in the aquarium and biofilters, but the net had no biofilm on it. Some microbiome from the water phase could be detected on the net, but not as attached biofilm. This net section was not deployed to sea due to its biotoxicity. The net with low concentration of antifouling coating were able to delay biofilm attachment for 5-6 weeks, and after three months there were some biofilm on the net, but not nearly as much as on the uncoated section. The microbiome richness was lower than the uncoated net.
The antifouling experiment was conducted in collaboration with Biotechnology students from NTNU, and the full thesis report is published in NTNU Open.
Contaminant of emerging concern (CECs) such as antibiotics, pathogens and antimicrobial resistant (AMR) bacteria in water bodies associated to intensive ?sh and inland animal farming, represent a great threat to the environment and human health. AMROCE aims at reducing antibiotic pollution and spread of AMR bacteria in the entire water cycle through a platform of novel antibiotic-free antimicrobial products. AMROCE will develop antimicrobial/antibio?lm ?sh cage nets and wastewater ?ltration membranes through polymer bulk and surface nano-engineering. Marine-derived antimicrobial agents and antibio?lm enzymes will be nano-formulated as alternative to antibiotics for ?sh and animal feed supplement. Human and environmental nanosafety during the manufacturing and use of the novel nanotechnology-embedded products will be continuously evaluated to anticipate nanosafety issues.