Discipline: Biomedical Science

Nowadays, plastic food packaging poses risks to the environment and human health. As a promising alternative, emulsion-based biodegradable film has attracted increasing attention. In this system, oil droplets are coated by the protein layers and suspended in the film homogenously to protect food products and extend their shelf life. Recently, the development of protein-phenolic conjugates as encapsulants has received much research interest due to potentially improved emulsifying, antioxidant, and antimicrobial properties, etc. Meanwhile, many literatures have proven the antioxidant and antimicrobial activities of essential oils.

This study investigates the reactions between food proteins and phenolic compounds. The effects of conjugation on proteins' solubility and emulsifying properties are determined. Then, the protein-phenolic compounds are used to encapsulate essential oil as an emulsion. Finally, emulsion-based films are prepared using the casting method, followed by measuring their functional properties. As an application, the fabricated film is applied to preserve cherry tomatoes. The quality and shelf life of the fruit are monitored to investigate the efficacy and effectiveness of protection.

Supervisor: Bo Wang (Principal Supervisor), Pre De Silva

Campus: North Sydney

Lipids rich in omega-3 fatty acids have been promoted as important dietary components to promote human health. However, these lipids are naturally susceptible and readily oxidised during food processing and storage. Therefore, they are commonly stabilised into protein-based powder form via the "microencapsulation" process to maximise their stability and facilitate the application. On the other hand, phenolic compounds are powerful antioxidants. In recent years, they have received increasing research interest due to their health benefits in preventing conditions like cognitive decline, cancer, and osteoporosis.

In this study, we aim to design a novel microencapsulation system to co-deliver omega-3 lipids using a protein-conjugate based system, followed by the bioaccessibility test. Omega-3 lipids are the "core material," while protein and phenolic compounds act as "wall materials". It is hypothesised that 1) The developed system can significantly enhance the oxidative stability of omega-3 lipids and 2) The designed microcapsules are digestible in the in-vitro gastrointestinal environment.

Targeted Cohort: Bachelor of Biomedical Science and Bachelor of Nutrition Science

Supervisor: Bo Wang (Principal Supervisor), Pre De Silva

Campus: North Sydney

Wasabi is a condiment used in Japanese cuisine that has some reported antibacterial activity against Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp. and Streptococcus spp. The active ingredient in Wasabi has been identified as 6-methylsufinylhexylisothiocyanate and there is some research evidence that it may have value as an additive to processed foods to limit potential food poisoning of these perishables.

Exploration of its use for medical conditions is limited and would benefit from further studies to elicit more precisely which bacterial organisms it might be effective in controlling growth together with an understanding of the concentration and formulation needed for use. For example, Wasabi at concentrations of 0.5% to 2% has previously been shown to limit the growth of both L. monocytogenes and Salmonella Typhimurium which is encouraging as this reduces the potential for unpleasant adverse effects likely at higher concentrations and favours its use clinically.

Possible applications include use as a disinfectant, topical cream for minor skin infections or as a component of an antibacterial mouth wash to control bacteria which contribute to dental caries, gingivitis, and periodontal disease.

This project aims to evaluate the antibacterial effects of Wasabi and its active ingredient (6-methylsufinylhexylisothiocyanate) against several available laboratory strains of bacteria together with the concentration required to reduce and/or prevent bacterial growth. This information will allow insight into the concentration and formulation of these agents to potentially manage bacterial growth of harmful organisms.

Techniques involved: agar plate preparation, culture of laboratory strains of bacteria, bacterial staining (including Gram stain) and microscopy, bacterial lawn culture and growth inhibition analysis. Formulation and serial dilution of compounds to be tested for antibacterial activity, inverted light microscopy for image analysis.

This study will be of interest to students with an interest in microbiology or development of antimicrobial compounds.

Supervisor: Roger Lord (Roger.Lord@acu.edu.au )

COVID-19 vaccination has involved a number of different vaccine constructs and with individuals receiving a varying number of doses and combinations of currently approved vaccines. Presently individuals from the age of 30 or more years can receive a 2^nd vaccine booster (4 doses) however effectiveness of available approved vaccines is challenged by the emergence of variants capable of eluding subsequent immunity.

Variants that are more easily transmitted between individuals, can cause reinfection, and promote changes associated with long COVID. The antibody response generated in response to vaccination, infection or reinfection will depend on several variables including age, gender, pre-existing medical conditions and medications along with the type of vaccine construct received and time since the last vaccination.

Currently there is much debate over how long protection following vaccination lasts and possible requirement for upgrades to current vaccines to protect against emerging variants. This project aims to gain insight into antibody responses in both vaccinated individuals and those who have had COVID-19 infection(s) via medical history and ELISA (micro drop) analysis of antibody responses against both S and N proteins.

This is a continuing project that is fully funded that began in 2022.

Techniques involved: clinical sampling for capillary blood from volunteers, processing of clinical samples, undertaking confidential medical history, ELISA (micro drop analysis) of antibody responses, statistical analysis.

This study will be of interest to students with an interest in immunology and clinical interaction with human volunteers.

Supervisors: Roger Lord and Francesca Fernandez

Magnesium is a mineral essential for healthy muscles, nerves, bones, and blood sugar levels. Normal plasma magnesium concentration is maintained by the kidney (0.8 to 1.10mml/L).

The Australian Department of Health (13 January 2023) reported that approximately 70% of the population are deficient in magnesium. Short-term magnesium deficiency can lead to muscle spasms and cramps and severe deficiency to arrhythmias and potentially cardiac arrest. Long-term deficiency increases the chances of developing hypertension, type 2 diabetes, osteoporosis, and migraine headaches.

Magnesium deficiency can be a result of poor diet but also includes those with digestive problems (e.g. Crohn's disease), persistent vomiting or diarrhoea or overuse of diuretics or drugs to treat Gastro-oesophageal reflux disease (GORD).

Magnesium levels in the body can be depleted by excessive consumption of processed foods, high sugar content and coffee and alcohol consumption and which may explain the apparently high prevalence of low magnesium intake in the Australian population.

In a university context, lower levels of magnesium may also offer insight into elevated levels of anxiety in students, increased stress, and student retention in degree programs.

This project seeks to gain a better understanding of measured magnesium levels in students over several time points during an academic semester via the use of saliva-based and or plasma ELISA measurement together with a confidential medical history covering elements that affect magnesium intake and absorption.

Supervisor: Dr Roger Lord

The honours' students involved in these projects will investigate new pathways involved in Alzheimer's Disease using human brain tissues, saliva and blood samples.

Supervisor: Associate Professor Francesca Fernandez (Francesca.Fernandez@acu.edu.au)

Campus: Brisbane