Percorrer por autor "Dias, Albino A."
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- Enzymes and secondary metabolites profiles of Gnomoniopsis smithogilvyi are affected by chestnut mediumPublication . Sampaio, Ana; Camelo, Verónica; Fraga, Irene; Gomes, A.; Sulyok, Michael; Gomes-Laranjo, José; Dias, Albino A.; Rodrigues, PaulaChestnut tree (Castanea sativa Mill) is a crop with high economic and social importance in Trás-os-Montes Region. The pre and post-harvest quality of its nuts can be affected by many factors, being the lasses dueto fungi very large. During the last decade a new endophyte fungus, Gnomoniopsis smithogilvyi, causing brown rot, has been isolated from both rotten and healthy fruits, and its growth seems to be related with the increase of air temperatura and rainfall during spring. The present study aims to understand the influence of chestnut substrate on G. smithogilvyi biochemistry, in arder to develop strategies to reduce its incidence in the fruit and improve the contrai of brown rot. lnitially, the presence of the enzymes involved in the decomposition of chestnuts, such as amylase, proteases, carboxymethylcellulase (CMCase), ~-glucosidase, xylanase, among others, was investigated. Further, some hydrolase activities were evaluated in two isolates of G. smithogilvyi incubated in potato (PDB) and chestnut media (CM) along an incubation period (3, 7 and 14 days), in arder to study the effects "isolate", "medium" and "incubation period" on enzymes production. Also, the synthesis of secondary metabolites in fungai dry biomass was assessed by Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Ali isolates produced the enzymes screened and, in general, the enzyme production varied between the isolates (P< 0.0000), the media (P< 0.0000) and along the incubation period (P< 0.0000). Amylase activity was positively correlated with xylanase (P< 0.0001), CMCase (P< 0.0001), and Avicelase {P< 0.01), xylanase with CMCase (P< 0.01) and ~-glucosidase with Avicelase (P< 0.0001 ). By contrast, ~-glucosidase was negatively correlated with CMCase {P< 0.01 ). Twenty secondary metabolites were detected along the incubation: eight in both isolates and media, tive and three only in isolates grew in PD o r CM, respectively. Some of these metabolites had been associated with other fungi and have known biological activities.
- UV Radiation: Applications on Surfaces in the Food IndustryPublication . Maioto, Rita; Santos, Stefanie; Dias, Albino A.; Aires, Cristina; Inês, António; Sedrine, Nabiha Ben; Mendes, Paulo; Rodrigues, Paula; Sampaio, AnaUltraviolet radiation, particularly in the UVC sub-band 200–280 nm, is a non-thermal disinfection technology capable of inactivating a broad spectrum of microorganisms primarily through nucleic acid damage and protein oxidation. Its effectiveness depends on wavelength, irradiance, exposure time, environmental conditions, and microbial characteristics, such as species and repair capacity. In food processing environments, where equipment surfaces and packaging materials are critical control points for microbial contamination, UVC offers several advantages, including the absence of chemical residues, and compatibility with sustainable sanitization strategies. However, efficacy is strongly influenced by surface properties. Smooth, non-porous, reflective materials (stainless steel, glass), and photocatalytic metal coatings, enhance UVC performance, whereas rough, porous, or fibrous surfaces reduce penetration and create shadowing effects that limit microbial inactivation. This review synthesizes current evidence on UV-based decontamination in the food industry, highlighting both its potential and limitations. The findings emphasize that, although UVC radiation is effective in microbial control, its implementation must consider the complex interactions between surface properties, microorganisms and irradiation parameters, requiring optimization for each environment and application. Further research is therefore needed into: (i) wavelength-tuned systems, (ii) hybrid technologies (UV–plasma or UV-photocatalysis), (iii) material integrity and durability of materials under repeated exposure, and (iv) emerging alternative light sources.