https://www.um.edu.mt/library/oar/handle/123456789/8430 2026-04-27T15:45:59Z https://www.um.edu.mt/library/oar/handle/123456789/145572 Title: A study of factors affecting fruit and vegetable consumption and a retail assessment in selected districts in Malta Abstract: Background: Fruit and vegetable (FV) consumption is a foundation of a healthy diet, with the World Health Organization and Food and Agriculture Organisation of the United Nations jointly recommending at least 400 g (roughly five portions) per day to reduce non-communicable disease risk. In Malta, over one in four adults live with obesity and only ~12 % meet the five-a-day intake. This study aimed to assess FV intakes and drivers, particularly barriers, among adults aged 18-65 years in Malta and explore the local FV retail environment across two selected districts. Methods: The study included two phases. The first phase consisted of a 33-question, cross-sectional, anonymised survey, which was adapted, translated and piloted for Malta, then distributed online via Google Forms using convenience sampling Questions covered FV consumption, local retail environment perceptions and socio-demographic characteristics. The second phase focused on the assessment of FV retail outlets selected in two selected districts, the Northern Harbour and South Eastern districts. This assessment included measuring the number of retail outlets in 4 different localities, mapping their locations using Geographic Information Systems (GIS), and collecting data on the quality and cost of selected FV in eleven conveniently selected outlets within 4 different localities. Results: Data from 315 respondents (mean age 44.5 years; 72.4 % female; mean BMI 26.4 kg/m2) were analysed using Chi-square or Fisher-Freeman-Halton exact tests, Spearman’s correlations and cross-tabulations. Mean daily intake was 1.7 fruit and 1.8 vegetable portions. Around 51.0% of participants were classified in the overweight and obese ranges. Fruit intake increased with age (p < .05) and decreased with higher BMI (p < .05). Cost barriers were significant among lower-income households (p = .001), non-EU nationals (44.4 %, p < .001) and younger adults (p < .001). Larger households consumed more vegetables (p=0.003), but no significant associations were found between consumption frequency and gender, education or taste preferences (p >.05). Regarding shopping habits, 64.7 % of respondents travelled to purchase FV by car, while 44.8 % went on foot. Main desired improvements to better FV intake included lower prices (57.5 %), better quality (37.5 %) and more variety (28.4 %). Comparing the two selected districts, tests showed no difference in FV intake (p>.20). Quality and price assessments revealed that visual defects, °Brix and pH influenced retail prices across multiple crops (p<0.05). Spatial analyses confirmed that there was good availability of FV outlets in two most populated towns of selected districts and most participants lived within a 5-minute walk of an FV outlet. Discussion: FV intake in Malta remains relatively low, particularly among younger, lower-income and non-EU groups, similar consumption across districts. Affordability emerged as the primary barrier. Targeted interventions, such as subsidies for vulnerable pockets and community-tailored educational campaigns, are needed to boost FV consumption and reduce chronic disease risk. Description: M.Sc.(Melit.) 2025-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/141775 Title: Prevalence of legionella pneumophila from water sources in the Maltese Islands Abstract: This project has dealt with the prevalence of Legionella pneumophila and other indicator organisms from water sources used in educational, industrial, health institution and recreational environment in Malta and Gozo. A previous study related to the detection of Legionella species in Health Institutional facilities had been performed in 2005 but it did not include the current General Acute Teaching Hospital (GATH) included in this study which accepted patients in late 2007. Another study involving testing of water samples for Legionella was carried out in 2013 and it involved testing of 27 samples from the Maltese Islands which included five water samples from water fountains (Blundell, 2014) . Other studies on Legionella recorded did not involve laboratory-based tests. According to the Annual Epidemiological Report published by the European Centre for Disease Prevention and Control (ECDC) for 2019, there were 5 cases of Legionnaires’ disease recorded in Malta but none resulting in death (ECDC, 2021) [...] Description: M.Phil.(Melit.) 2023-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/132385 Title: Evaluating the effect of plasma activated water on keratinocytes Abstract: Rising antimicrobial resistance has highlighted the need for alternative and novel disinfection technologies. Cold atmospheric plasma and its application to solutions such as plasmaactivated water (PAW) fulfil the requirement of a novel technique with antimicrobial characteristics. The suitability of such a product for use as a hand sanitiser would require a balance between antimicrobial efficacy and safety for dermal application. To this end, immortalised keratinocyte cell lines N/TERT1 and N/TERT2G were exposed to PAW for 5 minutes, and cytotoxic markers were evaluated. Specifically, post-exposure cellular viability was assessed using a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay, and the secretion of immune-response-related cytokines IL-1α, IL4, IL-6, and IL-8 was measured using ELISA. Membrane integrity was evaluated for lipid peroxidation via a TBARS assay, and potential mitochondrial dysregulation was assessed using JC-1 fluorescence. Cleaved caspase-3 was assessed as an apoptotic marker, and potential oxidative stress was evaluated by measuring Glutathione (GSH) concentrations and Superoxide Dismutase (SOD) activity. Exposure to PAW decreased viability similarly to water, to 90% in N/TERT1 and 80% in N/TERT2G; however, this was not statistically significant. No apoptotic induction or cellular dysregulation was indicated as a result of PAW exposure. The GSH concentration increased fivefold upon challenge with PAW in N/TERT2G (p < 0.05), but no such effect was observed in N/TERT1 keratinocytes. The SOD activity remained unaffected following exposure to PAW in both cell lines, indicating that the GSH pathway is sufficient to mitigate oxidative stress. No lipid peroxidation occurred in either N/TERT1 or N/TERT2G keratinocytes following exposure to PAW. Similarly, the mitochondrial membrane potential was also comparable to that of the untreated control cells. Together, these findings demonstrate that transient application of PAW is safe for dermal use. Slight variations in the responses from both cell lines highlight the potential biological variation that can be found in a non-clonal population, emphasising the need for further studies to account for such variation. Moreover, testing must also be carried out on in vitro models to further ensure the safe use of PAW as a topical disinfectant. Description: M.Sc.(Melit.) 2024-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/128697 Title: Microbiological analysis of Maltese dry sausages : isolation of lactic acid bacteria and assessment of their survival to low pH, as a basic in vitro probiotic attribute Abstract: Background: Fermented dry sausages are traditional food products, commonly consumed in the Mediterranean region. These products rely on natural fermentation processes driven by indigenous microbiota and have unique attributes influenced by local microbiota, ingredients, and processing methods. Traditional Maltese dry sausages have yet to be comprehensively studied for their microbial composition and probiotic potential. This dissertation aims to explore the microbial population dynamics of Maltese dry sausages and evaluate the acid tolerance of lactic acid bacteria (LAB) strains isolated from these products to assess their probiotic potential. Methodology: Five samples of traditional Maltese dry sausages, with no added starter cultures were collected, from different local butchers. Microbiological analysis was conducted to enumerate various bacterial groups, including Escherichia coli, Enterobacteriaceae, Total mesophilic count, Salmonella, Yeasts, and moulds, lactococci, and LAB. LAB strains were isolated using de Man, Rogosa, and Sharpe agar (MRS). Their resistance to low pH (pH 2.5) was tested to assess their acid tolerance. Resistance was assessed through viable colony counts at 0, 0.5, 1, 2, and 3 hours. Statistical analysis used the test of analysis of variance (ANOVA) to identify significant differences in survival rates (p < 0.05). Results: Microbial analysis revealed variations in microbial populations across different sausage samples, with LAB strains dominating on MRS and M17 media. This indicates the potential responsibility of LAB for fermentation processes. The acid tolerance test on isolates obtained from MRS showed a marked decrease in survival rates over a 3-hour incubation period, with none of the strains having a final population exceeding 103 CFU/mL at the 3-hour time point. This finding suggests potential limitations in the probiotic potential of the specific LAB isolates, since microorganisms classified as probiotics typically demonstrate robust acid tolerance. Conclusion: The study sheds light on the microbial composition of traditional Maltese dry sausages and underscores the importance of further research to elucidate the probiotic potential of LAB strains in these food products. Future research should address limitations such as small sample sizes and resource constraints, while also conducting comprehensive probiotic assessments to better understand the health benefits associated with LAB strains in traditional Maltese cuisine. Description: B.Sc. (Hons)(Melit.) 2024-01-01T00:00:00Z