Ana Sampaio

• PhD. Biology/Microbiology
• Associate Professor at University of Trás-os-Montes e Alto Douro - Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)

The 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, s...

Aflatoxins constitute a significant risk in staple foods produced in African countries. This research aimed to analyze the total aflatoxin (AFT) contamination of various staple foods in Angola and Mozambique. A total of 233 samples of corn, peanuts, beans, rice, and cassava flour collected from farmers or local markets from the province of Cuanza S...

Fungal flora in coastal/inland beach sand and recreational water is a neglected field of study, despite its potential impact on human health. A joint International Society for Human and Animal Mycology/European Confederation for Medical My cology (ISHAM/ECMM) w orking group w as formed in 2019 with the task to set up a vast international initiative...

BACKGROUND Gnomoniopsis smithogilvyi is the major chestnut pathogen, responsible for economic losses and recently described as a 3‐nitropropionic acid and diplodiatoxin mycotoxin producer. Bacillus amyloliquefaciens QST 713 (Serenade® ASO), B. amyloliquefaciens CIMO‐BCA1, and the fungicide Horizon® (tebuconazole) have been shown to reduce the growt...

Sweet chestnut (Castanea sativa Miller) is a nutritious food with high social and economic impacts in Portugal. The fungus Gnomoniopsis smithogilvyi (syn. Gnomoniopsis castaneae) is the causal agent of chestnut brown rot, and is currently considered one of the major threats to the chestnut production chain worldwide. Considering the lack of knowled...

Mycotoxins are toxic metabolites produced by various moulds that frequently contaminate food worldwide, being significant contributors to food losses in developing countries. In Mozambique, there is no comprehensive knowledge of the risk of mycotoxins in the country, nor structured actions to reduce the impacts of mycotoxins and promote health and...

Gnomoniopsis smithogilvyi (Gs) is a relevant pathogen of chestnut since it provokes significant losses worldwide. The aim of this study was to screen the effect of a new biocontrol agent (BCA) against Gs isolated from chestnut (CIMO-BCA1) on the mould’s growth as well as on the production of secondary metabolites. The chemical fungicide Horizon® (t...

Gnomoniopsis smithogilvyi is the main causal agent of chestnut brown rot in post-harvest nuts, a threat to the sustainability in the European market. With the objective of reducing the infection levels in chestnuts, the impact of commercial products application in G. smithogilvyi control was evaluated at the field. Trees with 8-years-old of the 'Bo...

Sweet chestnut fruits are popular fruits commercialized as fresh or processed ready-to-eat products. The major post-harvest problems associated with stored chestnut fruits are fungal rots, which cause major losses in fruit quality. The aims of this work were to determine the incidence, abundance and diversity of rots and fungi in three chestnut var...

The present study employed data collected during the Mycosands survey to investigate the environmental factors influencing yeasts and molds distribution along European shores applying a species distribution modelling approach. Occurrence data were compared to climatic datasets (temperature, precipitation, and solar radiation), soil datasets (chemic...

In general, the assessment of microbiological quality in aquatic systems focuses on the presence of some bacterial groups or species. Although quantification of fungi presence is not a mandatory parameter, recently the WHO advises its detection/quantification. Its concentration and diversity varies greatly among the various types of aquatic systems...

Há cerca de 2,0 x 10^9 anos surgiram os primeiros Eucariotas. A teoria Endossimbiótica, formalmente apresentada pela microbióloga Lynn Margulis, postula que os Eucariotas atuais se formaram a partir de endossimbioses com bactérias, que permaneceram no interior das células ao longo do tempo, originando as mitocôndrias e cloroplastos — estes últimos...

In this study, chestnut shells (CNS), a recalcitrant and low-value agro-industrial waste obtained during the peeling of Castanea sativa fruits, were subjected to solid-state fermentation by six white-rot fungal strains (Irpex lacteus, Ganoderma resinaceum, Phlebia rufa, Bjerkandera adusta and two Trametes isolates). After being fermented, CNS was s...

Vibrios are ubiquitous bacteria in aquatic systems, especially marine ones, and belong to the Gammaproteobacteria class, the most diverse class of Gram-negative bacteria. The main objective of this review is to update the information regarding the ecology of Vibrio species, and contribute to the discussion of their potential risk in a changing envi...

Natural aquatic environments represent one of the most important vehicles of bacterial dissemination. Therefore, we aimed to isolate staphylococci from surface waters and to investigate the presence of antimicrobial resistance genes and virulence factors as well as the genetic lineages of all Staphylococcus aureus isolates. Staphylococci were recov...

Staphylococcus aureus (S. aureus) are one of the best-known opportunistic pathogens capable of causing different types of infections in animals. Furthermore, it has the ability to acquire resistance to various antibiotics very easily. Methicillin-resistant S. aureus (MRSA) are currently of great concern as they are the leading cause of infections i...

This work intends to promote the growth of microalgae biomass with simultaneous remediation of an agro-industrial wastewater. Winery wastewater (WW) was used as growth media for the cyanobacteria Arthrospira maxima and the green microalgae Scenedesmus obliquus, Auxenochlorella protothecoides and Chlorella vulgaris, under mixotrophic and heterotroph...

The purpose of paper was to study the antibacterial activity of 2-methyl-1-hydroxymethylimidazole, the hemiaminal of 2-methylimidazole (HIM) by using macrodilution broth method and time-kill assay. Average inhibitory activity of HIM was moderate and its ability to kill bacteria was variable, and displayed a concentration-dependent pattern. Most evi...

The goal of most studies published on sand contaminants is to gather and discuss knowledge to avoid faecal contamination of water by run-offs and tide-retractions. Other life forms in the sand, however, are seldom studied but always pointed out as relevant. The Mycosands initiative was created to generate data on fungi in beach sands and waters, of...

Candida albicans is a commensal yeast that may become pathogenic and even lethal to the host. Over the last few decades, antifungal resistance has increased, promoting screening of the antifungal potential of old and new substances. This study investigates the antifungal potential of isothiocyanates (ITCs) against C. albicans oral isolates. A preli...

Grape stalks, an inedible lignocellulosic residue from winemaking and agro-industrial grape juice production, can be valorized as a source of bioactive compounds and as feedstock for the saccharification and bioconversion of soluble sugars. Solid-state fermentation (SSF) by six white-rot fungi was applied as pretreatment. Fiber composition, free ra...

The wastewaters from distilleries of winemaking by-products, a scarcely studied type of vinasse, were treated by white-rot fungal strains from species Irpex lacteus, Ganoderma resinaceum, Trametes versicolor, Phlebia rufa and Bjerkandera adusta. The main objectives of this study were to evaluate fungal performance during vinasse biodegradation, the...

Polyphenols are widely spread in the plant kingdom as products of secondary metabolism. They are known for a series of biological properties that influence human health, and evidence exists that people can benefit from plant phenolics obtained either from diet or through skin application, because they can alleviate symptoms and inhibit the developm...

Vinasses obtained from the distillation of winemaking by-products (WDV) are complex effluents with variable physicochemical properties. Frequently, WDVs are used to irrigate agricultural soil, and/or discharged into aquatic bodies, which may result in serious environmental pollution, due to the presence of organic acids and recalcitrant compounds (...

Forested wetlands are interfaces between terrestrial and aquatic environments. These ecosystems play an important role in the hydrology, chemistry and biodiversity maintenance. Despite their high microbial diversity, there has been a lack of attention to the potential of their yeast communities. The purpose of this study is to evaluate the potentia...

The occurrence of fungi in water samples from five sites in three streams (Olo-station Lamas de Olo, OL; Corgo-stations Zimão CZ, Benagouro CB and Flores CF; and Pinhão-station Balsa, PB) located in Douro river basin (NE Portugal) was followed over time 2.5 years, in winter and summer, in order to study its dynamics and relations with environmental...

The production of grapes is an important socioeconomic activity being the major part addressed to alcoholic fermentation in order to obtain different types of wine. Huge amounts of biodegradable winery wastes (mainly solid residues) are generated annually by winemaking industries. Taking into account the incorporation of recent concepts included in...

Freshwater disinfection using photolytic and catalytic activation of peroxymonosulphate (PMS) through PMS/UV-A LED and PMS/Mⁿ⁺/UV-A LED [Mⁿ⁺ = Fe²⁺ or Co²⁺] processes was evaluated through the inactivation of three different bacteria: Escherichia coli (Gram-negative), Bacillus mycoides (sporulated Gram-positive), Staphylococcus aureus (non-sporulat...

Fundamental niche prediction of Cryptococcus neoformans and C. gattii in Europe is an important tool to understand where these yeasts have a high probability to survive in the environment and therefore to identify the areas with high risk of infection. In the present study occurrence data for C. neoformans and C. gattii were compared by MaxEnt soft...

Objective An instrument-free assay was developed for simultaneous detection of laccase activity in a large number of samples as diverse as screening of laccase-producing microbial cultures or chromatographic fractions. Method Dried paper discs previously impregnated with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) were placed on a flat-...

Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made. The two varieties within C. neoformans were raised to species level, and the same was...

Higher plants produce secondary metabolites involved in defense mechanisms against herbivores, pests and pathogens. These phytochemicals have also potential healthy properties on human organism, including antioxidant, antiinflammatory and anti-microbial. The pressure to discover and develop new and effective anti-infectious substances has grown due...

The inactivation of four different microorganisms, Escherichia coli, Bacillus mycoides, Staphylococcus aureus and Candida albicans, inoculated in simulated (SWW) and real winery wastewaters (RWW), was assessed by the first time using free sulphate and hydroxyl radicals from photolytic (UV-A LED radiation; 370 nm) and metal [Fe(II) or Co(II)] activa...

Solid lipid nanoparticles (SLNs) are used as carriers for drug delivery, and are high biocompatible and designed to endure in the host organism. Despite its current industrial production is low, many of these substances are available on the market, and much more are in the production pipeline. As a result, many of them will end in aquatic systems r...

Background: In Europe, Acacia and Eucalyptus, originate large amounts of biomass, due to their need by industries and other biological control, that can be used to extract antimicrobial substances. Materials and Methods: Foliar aqueous, ethanolic and methanolic extracts of Acacia baileyana (Cootamundra wattle), Acacia dealbata (silver wattle), Acac...

In order to elucidate the distribution of Cryptococcus neoformans and C. gattii in the Mediterranean basin, an extensive environmental survey was carried out during 2012–15. A total of 302 sites located in 12 countries were sampled, 6436 samples from 3765 trees were collected, and 5% of trees were found to be colonized by cryptococcal yeasts. Crypt...

In order to elucidate the distribution of Cryptococcus neoformans and C. gattii in the Mediterranean basin, an extensive environmental survey was carried out during 2012-2015. A total of 302 sites located in 12 countries were sampled, 6436 samples from 3765 trees were collected and 5% of trees were found to be colonized by cryptococcal yeasts. Cryp...

Leguminous cover crops improve the profitability and the sustainability of rainfed olive (Olea europaea L.) orchards: from soil biology to physiology of yield determination Abstract The olive sector has a crucial economic, social, cultural and ecological relevance in the Mediterranean region, where tillage and herbicides application still are gener...

Winery wastewaters (WW) have high levels of organic matter, resulting in high COD and BOD and suspended solids. This paper studies the combination of biological and chemical processes in WW treatment. Among 10 yeast isolates, Filobasidium sp. (AGG 577) and Cryptococcus laurentii (AGG 726) were selected due to their superior performance in COD remov...

This study evaluated a combination of biological and physical–chemical processes for pulp mill wastewater (PMW) treatment. Biological tests were performed with various yeasts to find out their capacity for growth at different temperatures in the effluent under study. Of the 8 yeast isolates, Cryptococcus podzolicus (AGG 691) proved to be the most a...

The Cryptococcus neoformans/C. gattii species complex members are the main agents of systemic cryptococcosis. This disease is believed to be acquired from the environment via fungal cell inhalation. Often, isolates recovered from environmental and clinical sources have proven to be genotypically similar. We assessed the occurrence of C. neoformans...

Objetivos: Avaliar se a colonização por microrganismos em brackets auto-ligáveis e brackets convencionais de aparelhos ortodônticos fixos é diferente nas mesmas condições de utilização e higiene oral. Materiais e métodos: Os participantes foram cinco pacientes da clínica de ortodontia da Faculdade de Medicina Dentária da Universidade do Porto em tr...

We conducted a microcosm study to assess the preferences of Procambarus clarkii (Girard, 1852), an invasive and successful crayfish species, for conditioned leaf litter from alder, oak, and plane with and without feces access. Some chemical foliar characteristics were determined at the beginning and at the end of the experiment. Alder and plane lea...

Solid state and submerged fermentations in the presence of white-rot basidiomycetes (Bjerkandera adusta, Fomes fomentarius, Ganoderma resinaceum, Irpex lacteus, Phanerochaete chrysosporium, Trametes versicolor and basidiomycete Euc-1) and the litter-decomposing basidiomycete Lepista nuda were evaluated as a pretreatment to increase enzymatic saccha...

Olive mill wastewaters (OMW) resulting from the extraction of olive oil possess high organic loads and elevated contents in phenolic compounds, which are usually toxic and recalcitrant to biological wastewater treatments. In this work, a strain of Candida oleophila isolated from olive wastewaters was used for biological detoxification treatments of...

Forty Candida albicans strains isolated from patient's mouth with fixed orthodontic appliances were analyzed to their susceptibilities to antifungal agents, mouth rinses and essential oils. Susceptibility to fluconazole, econazole, miconazole and ketoconazole, amphotericin B and nystatin was assessed by the disk diffusion (DD) method based on the C...

Na região Mediterrânea ocorrem várias formações vegetais arbustivas que surgiram como resultado das condições ambientais e pelas acções humanas. As plantas mediterrânicas, como o medronheiro (Arbutus unedo L.) e o sumagre (Rhus coriaria L.), apresentam adaptações estruturais e fisiológicas que lhes permitem sobreviver às condições ambientais desfav...

Na região Mediterrânica ocorrem várias formações vegetais arbustivas que surgiram como resultado das condições ambientais e pelas acções humanas. O medronheiro (Arbutus unedo L.) é um arbusto da família das Ericáceas com ampla distribuição na região mediterrânica. A sua capacidade de adaptação a condições de stresse faz dela uma espécie altamente c...

Uma das características das plantas é a existência de metabolismo secundário, onde são sintetizados vários compostos, alguns dos quais com aptidões terapêuticas. No presente trabalho prepararam-se extractos etanólicos de folhas, casca de caules e de raízes de sumagre (Rhus coriaria), com o objectivo de avaliar a sua acção em Bacillus cereus, Bacill...

Wheat straw was submitted to a pre-treatment by the basidiomycetous fungi Euc-1 and Irpex lacteus, aiming to improve the accessibility of cellulose towards enzymatic hydrolysis via previous selective bio-delignification. This allowed the increase of substrate saccharification nearly four and three times while applying the basidiomycetes Euc-1 and I...

Water resources are being, over decades, intensively over explored and polluted, and it is estimated that in a few years, it is reached highly values of water stress in Europe. Portugal is already in the ranking of countries with medium water stress (10-20%). To avoid the deterioration of this situation it is imperative to consider different approa...

Fluorescence in situ hybridisation (FISH) is a suitable technique for the rapid, reliable and cultivation-independent identification of microbial pathogens. This study describes the development of fluorescently labelled rRNA-targeted oligonucleotides and a FISH assay to detect and identify Cryptococcus neoformans in culture and biological samples....

Azo dyes are synthetically produced organic molecules and represent the largest group of commercial dyes. Industrial use for coloring purposes generates huge volumes of dyed effluents, which are of environmental concern. Color removal has been achieved by using microorganisms such as filamentous fungi, especially white rot fungi, and bacterial spec...

Water samples of 5 sites belonging to 3 streams of Douro River Basin (Portugal, NE) were analyzed regarding their hydrogeochemical and microbiological parameters. Two of the studied streams (Corgo and Pinhão) were strongly influenced by agricultural practices and construction pressures while the other stream (Olo) has low human impact. The study wa...

La descomposici´on de hojarasca se utiliza frecuentemente para medir la integridad estructural y funcional en los sistemas acu´aticos. Los humedales arbolados son sistemas de transici´on que han recibido escasa atenci´on especialmente en la Península Ibérica. El presente trabajo compara la descomposici´on de la hojarasca de aliso y sauce en dos sis...

Here we report on the results of a survey of the yeast populations occurring on submerged leaves (alder, eucalyptus and oak) in a natural mountain stream, during different phases of their decomposition and through two consecutive years. Leaf litter mass loss, total yeast counts, Shannon-Weiner index (H'), yeast community structure and physiologic a...

This work presents the results of our studies on the decolorization of aqueous azo dye Reactive black 5 (RB5) solution combining an advanced oxidation process (Fenton's reagent) followed by an aerobic biological process (mediated by the yeast Candida oleophila). Under our conditions, initial experiments showed that Fenton's process alone, as well a...

Wastewater treatment plants, such as activated sludge and methanogenic reactors, are not the natural habitat of WRF, since these organisms prefer solid substrates and well-aerated environments. The fact, that constructed wetlands (e.g. sub-surface flow systems with rooted emergent macrophytes), are transitional environments, i.e. are intermediate b...

This work looks for a better understanding of the biodegradation of xenobiotic azo dyes mediated by yeasts. During a screening program of phenolic acid assimilating capacities it was found that a non-conventional ascomycetous yeast isolate, identified as Candida oleophila, efficiently decolorizes agar plates supplemented with the commercial textile...

The composition of yeast and macroinvertebrate communities was studied on black alder, blue gum eucalyptus and English oak leaves decaying in a stream during a six-month period. ANOVA analysis showed significantly different values (p < 0.0001) of yeast and macroinvertebrate densities among the three leaf litters. Some yeast species such as Cryptoco...

Decomposition of three leaf species (Alnus glutinosa, Eucalyptus globulus and Quercus robur) were examined in a headstream. During two months decomposing leaves were periodically analysed for nutrient content, soluble sugars, phenols, protein precipitation capacity, total fiber, weight loss, microbial and macroinvertebrate colonisation. The leaves...

Decomposition of three leaf species (Alnus glutinosa, Eucalyptus globulus and Quercus robur) were examined in a headstream. During two months decomposing leaves were periodically analysed for nutrient content, soluble sugars, phenols, protein precipitation capacity, total fiber, weight loss, microbial and macroinvertebrate colonisation. The leaves...

A construção de estruturas hidráulicas fluviais transversais altera os processos físicos, químicos e biológicos dos ecossistemas lóticos. Com o objectivo de avaliar a influência de pequenas estruturas deste tipo desenvolveu-se um estudo em vários troços de rios regularizados no Norte (rios, Corgo, Sabor, Alvadia e Balsemão) e Sul (ribeiras de Tera,...