Film of the Future - Producing an antiviral, antimicrobial, biodegradable plastic from seaweed

The increasing consumer concern about the impact of plastic pollution on the environment is neatly on trend. The government is promoting investment towards single-use plastic eradication and media attention is focused on alternatives to this material1,2. We are also facing COVID-19, declared global pandemic in 20203. This virus can survive on plastic packaging materials, and be transmitted to the consumer. Key sectors within the food supply chain rely on plastic packaging to ensure the food safety and quality. For example, Samworth Brothers (SB) produce prepared food products (e.g. sandwiches, ready meals, snacks) across the branded and 'own label' market and are keen to offer their consumers a more environmentally responsible packaging solution that could not only replace plastic packaging but also have further antibacterial and antiviral benefits.
Fully compostable films produced from the seaweed derivative alginate were first patented in 1949 using a cost-effective process involving CaCl2 and HCl4. These films can be enhanced with compounds to provide antiviral and antimicrobial properties like fucoidan, phloroglucinol and laminarin, also present in brown seaweeds5,6.

We hypothesise that fully compostable non-plastic films can be produced containing extracts from seaweeds with antibacterial and antiviral properties, minimising the risk of disease transmission through food contact materials; maintaining quality and safety of food products; and reducing the environmental impact of current packaging solutions.

Objectives
1: Substrate generation and desirable property analysis (AU)
Extracts formed of fucoidan and phloroglucinols will be extracted from brown seaweed species (Laminaria digitata, Laminaria hyperborea, Saccharina latissima, Fucus vesiculosus, Fucus serratus, Ascophyllum nodosum). An industrially scalable extraction method will be developed to enable fractional separation of different molecular weights in addition to whole extracts. The antibacterial properties of each extract will be tested in in vitro trials using standard aerobic test strains (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica subsp. enterica, Candida albicans). Antiviral properties will be examined 7 using viruses P100, MS2 and Phi6, models for non-enveloped DNA viruses; non-enveloped RNA viruses and enveloped RNA viruses respectively.
2: Existing and future packaging solution study (SB)
Placement to study existing packaging processes to better understand what the key parameters are within: prepared food packaging production, supply chain, quality control, and the packaging disposal process.

3: Film production (AU)
Films will be generated from commercially available alginate with products generated from Objective 1 and additional compounds with complementary properties addressing issues identified in Objective 2. Films will be screened for antibacterial and antiviral properties as per Objective 1.

4: Film property analysis (CU)
Selected films from Objective 3 will be characterised in terms of physical properties (e.g. gas permeability, flexibility, stability). Real-world supply chain conditions will be simulated to understand the response of food to novel packaging materials in terms of quality and safety.

5: Packaging production trial (AU/CU/SB)
Films identified with both positive packaging properties and antibacterial and antiviral qualities will be produced (AU), generating material sufficient for inclusion in a packaging trial (SB). Film samples will be taken throughout the process for physical property analysis (CU) and antimicrobial and antiviral property analysis (AU).

Justification:
Consumer demand for antiviral and antimicrobial packaging, especially those which are biodegradable, is anticipated to be high in future. The production of a viable seaweed-derived film fitting these requirements will generate highly impactful data for both industry and scientific communities