Browsing by Author "Rodrigues, C."
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- Antimicrobial activity of organic acids against some common food spoilage and pathogenic microorganismsPublication . Sorathiya, K.; Melo, A.; Rodrigues, C.; Paulico, L.; Barracosa, R.; Correia, D.; Pintado, M.Background: In recent years, the food industry is challenged to produce high-quality products using natural preservative alternatives instead of synthetic ones, owing to the increasing consumer demand for clean-label food products. Organic acids have potential as an alternative due to their antimicrobial activity and high food safety (GRAS). Therefore, the objective of this work was to investigate the antimicrobial activity of organic acids against some common food spoilage and pathogenic microorganisms for use in food formulation. Method: The antimicrobial activity of the organic acids (lactic, citric, and propionic acid) was tested at different concentrations ranging from 0.06 to 4% by microdilution method in 96 well plates against Lactobacillus plantarum, Escherichia coli; Candida intermedia, Pichia fermentans, Penicillium glabrum, and Aspergillus niger. The minimum inhibitory concentration (MIC) was recorded as the lowest concentration at which complete inhibition of visible growth occurred. Results: The MICs of lactic, citric, and propionic acid for E. coli were 0.25, 0.25, and 0.125% respectively, while for L. plantarum, they were 0.25, 0.25, and 0.06% respectively. Regarding the yeasts, the MIC of lactic, citric, and propionic acid for C. intermedia were 1, 2, and 0.125%, respectively and for P. fermentans they were 1, 0.5, and 0.5%, respectively. Propionic acid also shows fungicidal potential against A. niger and P. glabrum with MIC values 0.5 and 0.25, respectively. Lactic acid displayed a MIC value of 4% representing the highest MIC value observed for both, while citric acid did not inhibit these fungi. Conclusion: The organic acids tested showed significant antimicrobial potential at low concentrations, particularly lactic and propionic acids. Future studies will incorporate the most promising acids as substitutes for synthetic preservatives to verify their ability to maintain antimicrobial effectiveness over time when incorporated into foods.
- Antimicrobial activity of potential essential oils to replace potassium sorbate in fruit preparationsPublication . Melo, A.; Sorathiya, K.; Rodrigues, C.; Paulico, L.; Barracosa, R.; Pintado, M.Introduction: In recent years, the food industry has faced the challenge of producing high-quality products using natural preservative alternatives instead of synthetic ones. Essential oils (EO), naturally present in various plants, have potential as alternatives due to their antimicrobial activity and high food safety (Generally Recognized as Safe, GRAS). This study aimed to investigate the antimicrobial activity of EO against common spoilage and pathogenic microorganisms in fruit preparations, to use as a substitute for potassium sorbate (PS). Methodology: The antimicrobial activity of lemongrass and lemon EO was tested using the microdilution method in 96-well plates against Lactobacillus plantarum, Escherichia coli; Candida intermedia, Pichia fermentans, Aspergillus niger and Penicillium glabrum.EO were tested at concentrations ranging from 1.56 to 50% and PS at 0.03 to 4%. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. Results: The MICs of lemongrass and lemon EO for E. coli were 3.12 and 12.5%, respectively, while for L. plantarum, they were 1,56 and 6.25% respectively. Regarding the yeasts, the MIC of lemongrass and lemon EO for C. intermedia were 1.56 and 3.12%, respectively, and for P. fermentans, they were 1.56 and 1.56%, respectively. Lemongrass EO showed the same MICs value of 6.25% against A. niger, and P. glabrum. Lemon EO also displayed the same MICs values of 25% for A. niger, and P. glabrum representing the highest MICs values observed. The MBCs values was similar the MICs values to all microorganisms except to L. plantarum that were 6.25 and 25% to lemongrass and lemon EO, respectively. PS showed MICs values of 1 and 2% for E. coli and L. plantarum, respectively, with MBCs values of 2% for both. For yeasts, the MIC was 0.06% for both with MBC values of 0.06% for E. coli and 0.5% for L. plantarum. The MIC and MBC values were the same of 0.06% for both fungi. Conclusion: The EO tested showed significant antimicrobial potential at low concentrations, particularly lemongrass EO. Future studies will incorporate this oil as substitutes for PS to verify their ability to maintain antimicrobial effectiveness over time when incorporated in fruit preparations.
- Effect of pH upon viability of probiotic strains in contact with fruit pulpsPublication . Rodrigues, C.; Sousa, S.; Pinto, A. L.; Brandão, Teresa R. S.; Silva, Joana; Pintado, Manuela E.; Silva, Cristina L. M.; Morais, Alcina M. M. B.; Teixeira, Paula; Almeida, Domingos; Gomes, Ana M. P.
- Effect of pH upon viability of probiotic strains when in contact with fruit pulpsPublication . Rodrigues, C.; Sousa, S.; Pinto, A.; Brandão, T.; Silva, J.; Pintado, M.; Silva, C.; Morais, A.; Teixeira, P.; Gomes, A.; Almeida, D.In recent years many probiotic-containing products have been developed, being dairy and dried products the main vehicles for probiotic intake. Fruit juices have also been studied, with less good results, probably due to their low pH values, as well as to the presence of other components, adverse to the survival of the probiotic strains. In order to pinpoint possible reasons therefore, in this study we tried to evaluate the effect of the fruit pulp pH upon the survival of Lactobacillus acidophilus LA-5 and Bifidobacterium animalis BB-12. Two fruit pulps, with different pH values, were used, namely lemon (pH=2.5) and avocado (pH=6.5), and their pH was adjusted (to 2.5, 4.5 and 6.5), in order to access the effect upon probiotic survival over one week storage. Viability was evaluated at 0, 3 and 7 days. Results showed that, although the pH value is indeed important, it is not the only reason for low viability of probiotics when incorporated in fruit pulps. Viability was, as expected, the highest when the pulps had a pH value of 6.5. At 4.5, avocado still had considerable viable cell numbers after one week contact with the pulp, while for lemon, at the same pH, no probiotics were detected after 3 days. At 2.5, for both pulps, no viable cells were detected after only 3 days. These results indicate that, although pH is important, other constituents of the fruits are also responsible for the degree of survival of probiotics in fruit matrices.
- Recommendations for the implementation of a national lung cancer screening program in Portugal - a consensus statementPublication . Fernandes, M. G. O.; Dias, M.; Santos, R.; Ravara, S.; Fernandes, P.; Firmino-Machado, J.; Antunes, J. P.; Fernandes, O.; Madureira, A.; Hespanhol, V.; Rodrigues, C.; Vicente, C. A.; Alves, S.; Mendes, G.; Ilgenfritz, R.; Pinto, B. S.; Alves, J.; Saraiva, I.; Bárbara, C.; Cipriano, M. A.; Figueiredo, A.; Uva, M. S.; Jacinto, N.; Curvo-Semedo, L.; Morais, A.Lung cancer (LC) is a leading cause of cancer-related mortality worldwide. Lung Cancer Screening (LCS) programs that use low-dose computed tomography (LDCT) have been shown to reduce LC mortality by up to 25 % and are considered cost-effective. The European Health Union has encouraged its Member States to explore the feasibility of LCS implementation in their respective countries. The task force conducted a comprehensive literature review and engaged in extensive discussions to provide recommendations. These recommendations encompass the essential components required to initiate pilot LCS programs following the guidelines established by the World Health Organization. They were tailored to align with the specific context of the Portuguese healthcare system. The document addresses critical aspects, including the eligible population, methods for issuing invitations, radiological prerequisites, procedures for reporting results, referral processes, diagnostic strategies, program implementation, and ongoing monitoring. Furthermore, the task force emphasized that pairing LCS with evidence-based smoking cessation should be the standard of care for a high-quality screening program. This document also identifies areas for further research. These recommendations aim to guarantee that the implementation of a Portuguese LCS program ensures high-quality standards, consistency, and uniformity across centres.
- Salivary calprotectin: a potential biomarker in inflammatory bowel disease?Publication . Rodrigues, C.; Gomes, A.; Leal, J.; Mendes, K.; Correia, M. J.; Pereira, P.; Martins, R.; Nélio, V.; Rosa, N.; Soares, C.; Ministro, P.
- Survival of Lactobacillus Strains When In Contact With Fruit PulpsPublication . Sousa, S.; Rodrigues, C.; Pinto, A. L.; Brandão, Teresa R. S.; Silva, Joana; Pintado, M. E.; Silva, Cristina L. M.; Morais, Alcina M. M. B.; Teixeira, Paula; Gomes, Ana M. P.