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- Microbiome and Microbiota Within Wineries: A ReviewPublication . Aires, Cristina; Maioto, Rita; Inês, António; Dias, Albino Alves; Rodrigues, Paula; Egas, Conceição; Sampaio, AnaThe main goal of this work is to review the winery’s microbiota, from the grape to the winery’s microbial niches (fermentation tanks, surfaces, air), and their risks to wine and human health. The impact of climate change on the winery microbiome and related challenges are also discussed. Microbial diversity in wineries depends on several factors, such as the grape variety and its ripeness, temperature, relative humidity and the diverse activities of the winemaking process. Winery surfaces and equipment allow the establishment of a microbial community that can impact wine quality, the health of winery workers and visitors and even wine consumers. In the context of climate change, changes in the sugar content, phenolic compounds and the profile of hexoses and amino acids are already evident. These changes interfere with the fermentation microbiota and the quality of the wines, which are more alcoholic and less acidic. Furthermore, periods of drought or heavy rain favor species associated with berry diseases, including some capable of producing mycotoxins or harmful biogenic amines. In order to understand the impact of these changes on microbial communities, the use of various techniques will be discussed, such as flow cytometry, fluorescence in situ hybridization (FISH), quantitative polymerase chain reaction (qPCR) and metagenomic methods.
- Mixture of bee bread with honey: nutritional and microbiological characterizationPublication . Fortes, Adriana; Tomás, Andreia; Rodrigues, Paula; Vilas-Boas, Miguel; Martins, Vitor Manuel RamalheiraBeebread is a hive product produced in the honeycomb, through the lactic fermentation of pollen collected and partially processed by bees. This hive product has a chemical composition that makes it an interesting product, not only because of its nutritional value, but also related with its biological properties, such as antiinflammatory, anticancer, antinociceptive, and antidiabetic. In fact, beebread has earned some attention from the scientific community, being reported as a functional food with nutritional benefits, healing and preventive effects of some diseases.
- Editorial: Microbial safety of animal-based food productsPublication . Andrade, María J.; Álvarez, Micaela; Rodrigues, PaulaThe studies gathered in this Research Topic focus on several key areas to ensure the safety of animal food products. Firstly, rapid pathogen detection is being improved through technologies like SWIR-HSI combined with advanced machine-learning techniques. Secondly, the use of natural antimicrobials, such as essential oils delivered via liposomes, is being explored to combat microbial development while minimizing negative impacts on food quality. Thirdly, investigations have revealed a link between high crayfish consumption and rhabdomyolysis, emphasizing the need to control the toxins in the food chain. Finally, studies on the relationship between diet and colorectal cancer have suggested a potential inverse association between high fish intake and risk of developing colorectal adenoma, suggesting a possible preventative role for fish consumption. These combined efforts aim to enhance the safety and quality of animal-derived foods through advanced detection methods, natural preservation strategies, and a broader understanding of foodborne threats.
- Effect of γ-radiation in the survival of Aspergillus parasiticus in chestnutsPublication . Calado, Thalita; Antonio, Amilcar L.; Rodrigues, Paula; Venâncio, ArmandoIn this study, the use of rays as an inactivation agent agains one of the most ubiquous and mycotoxigenic fungus - Aspergillus parasiticus - was studied. Chestnuts were previous incoulated with a spore suspension of one strain of A. parasiticus. After irradiation the growth of colonies were observed during 4 days. In general, the higher level of radiation the lower survival rate.
- Ecophysiology of Penicillium expansum and patulin production in synthetic and olive-based mediaPublication . Hamdi, Mohamed; Bejaoui, Hend; Morais, Jorge Sá; Rodrigues, PaulaOlives and their derivatives, in particular olive oil, represent one of the most significant agricultural products in the Mediterranean basin. Storage under inadequate conditions poses serious problems concerning fungal contamination, with consequent defects and potential mycotoxin production in olives and olive oils. Penicillium expansum represents one of the most significant postharvest pathogens in several fruits, including olives. Not only it causes blue mold but also is one of the most relevant patulin producing species of the genus Penicillium. The aim of this research was to evaluate the ecophysiological conditions governing growth and PAT production by P. expansum strains previously isolated from Tunisian olives. For this purpose, four P. expansum isolates were tested in a synthetic medium (Czapek Yeast Autolysate, CYA) and in olive-based medium (OM) for their ability to grow and produce PAT under different temperatures (4 °C, 15 °C and 25 °C) for 10 and 20 d. The mycotoxin was analysed by HPLC-UV. Results showed that all isolates were able to grow on tested media at different temperatures. Different PAT production profiles were found, showing that at 25 °C P. expansum isolates were able to produce PAT on CYA and OM medium. At 15 °C the production of PAT was only detected on CYA medium, while no PAT production was detected at 4 °C for the two media.
- Distribution of aflatoxin M1 during production of sheep and goat cheesesPublication . Vaz, Andreia; Mendonça, Álvaro; Rodrigues, Paula; Venâncio, ArmandoThe occurrence of Aflatoxin M1 (AFM1) in milk results from ingestion of contaminated feed with Aflatoxin B1 by dairy animals, its conversion into AFM1, and secretion in milk. The objective of this work was to investigate AFM1 fate along goat and sheep cheese production. Cheese production was carried out using spiked milk (levels between 0.08 and 0.10 μg/L). Samples were collected throughout the production and analyzed by immunoaffinity cleanup and chromatography. Higher concentration of AFM1 was always observed in curd rather than in whey; with a mean enrichment factor of 1.8. A strong and positive correlation was established between casein content and AFM1 percentage in curd. Throughout production, a significant increase in AFM1 concentration on a wet basis was observed. In turn, on a dry basis, there was no statistically significant reduction during ripening. These observations are justified by the loss of cheese moisture and the absence of AFM1 degradation. Practical applications: The distribution of aflatoxin M1 during the production of two different cheeses was studied, where the amount of the toxin was monitored on a wet and a dry basis. On the wet basis, there was a continuous increase in concentration; which has already been reported by different authors, without clarifying whether this increase is due exclusively to the loss of moisture during milk processing. The same study on a dry basis allowed us to conclude that under the tested conditions, there is no degradation of the toxin, and the concentration increase observed previously was in fact due to the loss of humidity.
- A polyphasic approach to the identification of aflatoxigenic and non-aflatoxigenic strains of Aspergillus section flavi isolated from portuguese almondsPublication . Rodrigues, Paula; Venâncio, Armando; Kozakiewicz, Zofia; Lima, NelsonA polyphasic approach consisting of morphological, chemical and molecular characterization was applied to 31 isolates of Aspergillus Section Flavi originating from Portuguese almonds, with the aim of characterizing and identifying aflatoxigenic and non-aflatoxigenic strains. On the basis of morphological characters (mainly colony color on Czapek-Dox agar and conidia morphology), we found two distinct groups among the population under study: 18 isolates (58%) had dark-green colonies and rough conidia, and were classified as A. parasiticus; the remaining 13 isolates (42%) had yellow-green colonies and smooth to finely rough globose conidia, and were classified as A. flavus. Chemical characterization involved the screening of the isolates for aflatoxins B (AFB) and G (AFG), and also for cyclopiazonic acid (CPA), by HPLC with fluorescence and UV detection, respectively. All A. parasiticus isolates were strong AFB and AFG producers, but no CPA production was detected, showing a consistent mycotoxigenic pattern. The A. flavus isolates showed to be more diversified, with 77% being atoxigenic, whereas 15% produced CPA and low levels of AFB and 8% produced the 3 groups of mycotoxins. Aflatoxin production was also screened on Coconut Agar Medium (CAM), and the results were consistent with the HPLC analysis. Sclerotia production showed no correlation to aflatoxigenicity. Molecularly, two genes of the aflatoxin biosynthetic pathway, aflD (= nor1) and aflQ (= ord1= ordA) were tested for presence and expression (by PCR and RT-PCR, respectively). The presence of both genes did not correlate with aflatoxigenicity. aflD expression was not considered a good marker for differentiating aflatoxigenic from non-aflatoxigenic isolates, but aflQ showed a good correlation between expression and aflatoxin-production ability.
- Bacterial cellulose biosynthesis in the presence of raw moist olive pomace: A green sustainable approach that enhances biopolymer production and propertiesPublication . Crugeira, Pedro; Khelifa, Halima; Barreira, Luísa; Halla, Noureddine; Barreiro, Filomena; Rodrigues, Paula; Peres, António M.; Schreiner, Tatiana B.; Schreiner, Tatiana B.In this study, the biosynthesis of bacterial cellulose (BC) by Komagataeibacter intermedius strain isolated from Kombucha tea in the presence of raw moist olive pomace (MOP) (concentration up to 40 % in the fermentation media) was studied. The BC membranes were characterized by their antioxidant activity, structural character- istics, crystallinity, thermal stability, and mechanical behavior. Using raw MOP activated the inherent activity of the phenolic compounds, leading to cellular adaptation under unfavorable conditions and increased BC pro- duction for all tested MOP concentrations (p < 0.0001). This led to a 166.61 % increase for the 20 % MOP group compared to the control (HS medium). For this sample, enhanced antioxidant activity (~40-fold higher than the control) was found, which might be associated with the molecular interactions established between hydroxyls of BC and phenolic compounds. Moreover, an increase of 603.03 % in strain capacity, and a 376.01 % improvement in stress at break compared to the control was observed. The study confirmed that BC can be synthesized using MOP in its natural state, supporting a sustainable circular economy while enhancing the biosynthesis of a value- added product. By reducing synthetic media and utilizing MOP, a greener bioprocess can be achieved, and BC’s applicability can be expanded.
- Tools to develop dairy ingredients: bioactive and preservative purposesPublication . Khouja, Dora; Fernandes, Filipa Alexandra; Carocho, Márcio; Calhelha, Ricardo C.; Rodrigues, Paula; Zaghdoudi, Khalil; Barros, Lillian; Heleno, Sandrina A.; Ferreira, Isabel C.F.R.Phytosterols can be ingested and consequently absorbed by the human body, leading to a direct absorption competition with cholesterol, thus reducing its absorption [1]. Mushrooms are described as having several bioactive components, such as mycosterols (ergosterol), which, similarly to phytosterols, exhibit a strong hypocholesterolemic potential [2]. Thus, the objective of this work was to obtain mycosterol enriched extracts from A. bisporus L. bio-waste for further incorporation in sheep cottage cheese, in order to develop a functional food with hypocholesterolemic effects. Sheep cottage cheeses with pure ergosterol, and a control cheese with no incorporation were prepared. The extracts were obtained by ultrasound assisted extraction (UAE) and the identification and quantification of their compounds was achieved through HPLC-UV. The toxicity and hypocholesterolemic activity were sought through a CaCo2 cell line. In terms of analysis, the nutritional value was analyzed according to AOAC procedures, the physical parameters included texture, external colour and water activity, and the microbial load (total aerobic mesophiles, enterobacteria, Psychrotrophic bacteria, yeasts, molds and Staphylococcus aureus) was also analyzed along a shelf life of 9 days according to the International Organization for Standardization (ISO) 6887-1:2003 [3,4]. No significant differences were verified for the nutritional parameters. The color of the cheeses incorporated with the extract hinted towards a browner tone when compared to the other two samples (cottage cheese with ergosterol and control cottage cheese). A dominance of palmitic acid followed by oleic and capric acids was detected, being the saturated fatty acids the predominant ones. Lactose and glucose were the two detected soluble sugars; being glucose only observed in cheese incorporated with A. bisporus, probably present in the extract. Also, the incorporations did not cause any significant alterations to normal microbial growth. Despite an increase of enterobacteria in the cheeses with the incorporation of the two agents, this increase was also verified for the control cottage cheese. CaCo2 cells absorbed 43.89% of cholesterol from the control cheese, while the cheese with pure ergosterol reduced cholesterol absorption by approximately 21.1%, and cheese with A. bisporus by approximately 30.24%. These results highlight the capacity of ergosterol to reduce the absorption of cholesterol, being an interesting candidate for the development of functional foods.
- In vitro interaction of Amanita muscaria and Phytophthora cinnamomi: possible biocontrol effectPublication . Rodrigues, Paula; Martins, AnabelaInk disease, caused by the Oomycetes Phytophthora cinnamomi Rands. and Phytophthora cambivora (Petri) Buism., is a major soilborne problem in European chestnut (Castanea sativa) stands all over South Europe. Chemical treatments are not effective and comprise serious environmental and economic costs, so biological control is under study as a possible solution for this problem. Ectomycorrhizal (ECM) fungi are generally considered as potential biocontrol agents, for several of them have shown a positive effect on growth and survival of infected plants. The mechanisms underlying these effects are, however, still unknown. It is possible that they result from a chemical antagonism or a physical barrier of the ECM fungus over the pathogen, but other hypotheses involve active responses by the plant. Amanita muscaria is an important ECM fungus of C. sativa in the Northeast of Portugal. The present study intended to investigate a possible antibiosis effect of A. muscaria (Am) over P. cinnamomi (Pc). For this purpose, we used isolates of Am and Pc collected from a local chestnut orchard. The interaction between the organisms was tested by the dual culture technique on Petri dish, using mycelial inoculum, in two different culture media: MMN and PDA. The following dual cultures were tested: Am + Am, Pc + Pc, Am + Pc (inoculated simultaneously) and Am7→Pc (Pc inoculated 7 days after the inoculation of Am). Interaction was analysed daily for a period of seven days (given the rapid growth of Pc), and was based on radial growth and morphological features of both organisms. The growth of P. cinnamomi was heavily constrained by the presence of A. muscaria (in both Am + Pc and Am7→Pc dual cultures), and more spores were formed, when compared with Pc + Pc cultures. The results suggest a heavy antagonistic effect of the ECM fungus over the pathogen. Other ECM fungi are currently under study for the analysis and comparison of possible different effects over P. cinnamomi.