Os cogumelos contêm vários compostos antioxidantes nomeadamente, compostos fenólicos (e.g. ácidos fenólicos), tocoferóis e carotenóides. Entre as substâncias biologicamente ativas presentes nos cogumelos, os compostos fenólicos têm atraído muita atenção devido às suas excelentes propriedades como antioxidantes e ao seu potencial anti-inflamatório ou antitumoral [1,2]. Neste trabalho, foi avaliado o potencial antioxidante de seis espécies silvestres comestíveis do género Agaricus: Agaricus bisporus (Lange) Imbach, Agaricus campestris (L.), Agaricus comtulus Fries, Agaricus lutosus (Møller) Møller, Agaricus silvicola (Vittadini) Peck e Agaricus sivaticus Schaeff, obtidos no Nordeste de Portugal. Estudou-se a sua atividade captadora de radicais livres, poder redutor e inibição da peroxidação lipídica. Foram ainda analisadas algumas moléculas, nomeadamente açúcares e tocoferóis por cromatografia líquida de alta eficiência acoplada a deteção por índice de refração e fluorescência, respetivamente. Ácido ascórbico, carotenóides e fenóis foram obtidos por técnicas espectrofotométricas. O estudo realizado revelou que a espécie com maior teor de açúcares (20,87 g/100 g massa seca) e tocoferóis (160,43 μg/mL) foi A. bisporus e A. comtulos, respetivamente. Este último destacase, também, na atividade captadora de radicais livres (EC50= 2,22 mg/mL). A. lutosus demonstrou maior poder redutor (EC50= 0,91 mg/mL) e maior capacidade de inibição da peroxidação lipídica (EC50= 0,90 mg/mL). Esta mesma espécie revelou, ainda, a maior concentração de fenóis e ácido ascórbico. A presença de β-caroteno e licopeno não foi detetada em todas as espécies estudadas, mas A. silvaticus apresentou os maiores valores (5,42 e 2,63 mg/100 g, respetivamente). Com base no seu potencial antioxidante e compostos bioativos (vitaminas, carotenóides e fenóis), os cogumelos podem ser utilizados como fonte de nutracêuticos.

Natural products which grow in adverse conditions, such as fungi, are a possible rich source of biologically active compounds with potential for drug discovery [1,2]. We have recently reported the growth inhibitory activity of extracts from Clitocybe alexandri, a wild mushroom collected from the northwest of Portugal, in human tumour cell lines (NCI-H460, MCF-7, HCT-15 and AGS) [3]. The ethanolic extract was the most potent one, particularly in NCI-H460 cells (GI50 24.8 ± 2.3 μg/ml) [3]. The aim of this work was to further study the potential of this extract as a possible source of cytotoxic compounds. In order to understand the mechanism of action of this extract in the NCI-H460 cells, the effects on cell cycle (following PI labelling) and apoptosis (following AnnexinV/PI labelling) were evaluated by flow cytometry. Furthermore, the involvement of proteins related to cellular apoptosis was investigated by Western blot. The ethanolic extract was characterized regarding its phenolic composition by HPLC-DAD/ESI. The isolated compounds were also studied regarding their growth inhibitory activity, by SBR assay. The effect of isolated or combined compounds on viable cell number was also evaluated using the Trypan blue exclusion assay. It was observed that the Clitocybe alexandri extract induced an S-phase cell cycle arrest and increased the percentage of apoptotic cells. In addition, treatment with the GI50 concentration for 48h caused an increase in the levels of wt p53, cleaved caspase-3 and cleaved PARP. The main components identified in this extract were protocatechuic acid (16.4 ± 2.2 mg/kg dw), p-hydroxybenzoic acid (8.3 ± 0.4 mg/kg) and cinnamic acid (6.4 ± 0.3 mg/kg). Cinnamic acid was found to be the most potent compound regarding cell growth inhibition. Finally, it was verified that their concomitant use provided the strongest decrease in viable cell number.

Sterols are important molecules of the unsaponifiable fraction in several matrices. In mushrooms, ergosterol, which is an important vitamin D2 precursor, is clearly the main sterol. Hierarchical cluster analysis (HCA) is an unsupervised learning method to standardized data, checking for similarities between sample groups. This method calculates the distances (or correlation) between all samples using a defined metric such as squared Euclidean distance or Chebychev distance. Hierarchical clustering is the most common approach in which clusters are formed sequentially. The most similar objects are first grouped, and these initial groups are merged according to their similarities. Eventually as the similarity decreases all subgroups are fused into a single cluster. Herein, ergosterol was quantified by high performance liquid chromatography, coupled with an ultraviolet detector, in some of the most appreciated mycorrhizal edible mushrooms (Amanita caesarea, Boletus edulis, Cantharellus cibarius, Lactarius deliciosus and Morchella esculenta). Considering fat content (percentage) and ergosterol contents in mg/g fat and mg/100 g of dry weight, two main groups were formed in the HCA: one aggregating A. caesarea and B. edulis and another constituted by C. cibarius, L. deliciosus and M. esculenta. These two groups derived from the higher contents presented by B. edulis and A. caesarea. The detected values indicate that mushrooms might act as a potential source of this vitamin D2 precursor, with special relevance for diets deprived of food products of animal origin.

Our research group has an extensive work in the chemical characterization of wild mushroom species from the Northeast of Portugal. This region is one of the European regions with higher wild edible mushrooms diversity, some of them with great gastronomic relevance. In Europe, they are collected for consumption being a good source of digestible proteins, carbohydrates, fibers and vitamins. The present work reports the nutrients {fatty acids and sugars) and non-nutrients {phenolic acids) present on the wild species most appreciated in the Northeast of Portugal: Boletus edulis, Cantharellus cibarius, Lactarius deliciosus and Macrolepiota procera. Fatty acids and sugars were obtained by GC-FID and HPLC-RI, respectively [1-3]; Phenolic acids were analysed by HPLC-DAD-ESI/MS [4]. Furthermore their nutritional value was accessed through the composition in macronutrients and energetic value. Boletus edulis gave the highest energetic contribution and MUFA {mainly oleic acid) content; Cantarellus cibarius revealed the highest moisture and proteins levels; Lactarius deliciosus showed the highest ash, fat, SFA {mainly due to the specific contribution of stearic acid), sugars (total contribution of mannitol and trehalose) and phenolic acids {mainly p-hydroxybenzoic acid) contents; Macrolepiota procera gave the highest levels of total carbohydrates and PUFA. It was concluded that the most appreciated wild mushrooms have different nutrients and non-nutrients profiles and concentrations. This report contributes to the elaboration of nutritional data bases of the most consumed species, allowing comparison between them.

The implication of oxidative and nitrosative stress in the etiology and progression of several acute and chronic clinical disorders such as cancer, cardiovascular and neurodegenerative diseases, has led to the suggestion that natural antioxidants may have health benefits as prophylactic agents. Against this background, the possibility of including mushrooms, which contain significant amounts of bioactive phytochemicals, in our diets may provide desirable health benefits, beyond that of basic nutrition. Phenolic compounds might provide health benefits associated with reduced risk of chronic diseases which may relate to their ability to reduce agents by donating hydrogen and quenching singlet oxygen. It is our interest to characterize the phenolic composition of mushroom species and to understand if differences exist between the phenolic profile of edible and non edible species.

The objective of this study was to analyse the lipid peroxidation inhibition in beef burgers after incorporation of Boletus edulis extracts in different concentrations. Beef burgers samples were stored for 8 days, and chemical and nutritional parameters, including the profile in free fatty acids, were evaluated. Furthermore, the inhibition of thiobarbituric acid reactive substances (TBARS) formation, free radical scavenging activity and reducing power were determined. Polyunsaturated fatty acids arachidonic (C20:4n6) and cis-5,8,11,14,17-eicosapentaenoic (C20:5n3) acids were protected in the presence of mushroom extract. The antioxidant potential increased with the amount of extract added to beef burgers, giving higher radical scavenging properties and TBARS inhibition capacity. These findings indicated that beef burgers patties were protected from lipid peroxidation in the presence of mushroom extract.

Mushrooms are a vast and yet largely untapped source of powerful new pharmaceutical products. In particular, and most importantly for modern medicine, they represent an unlimited source of compounds with antitumor and immunostimulating properties [1). Particularly, the intake of some wild mushrooms has shown to reduce the risk of breast cancer in Chinese women [2] and inhibited the proliferation of human tumour cell lines [3].

The main objective of the present work was to evaluate the capacity of wild mushroom extracts to potentiate the action of standard antibiotics, through synergisms that allow a decrease in their therapeutic doses and ultimately contribute to the reduction of resistances. Methods and Results: Wild mushroom extracts were applied to different multi-resistant microorganisms (Escherichia coli, Extended-spectrum beta-lactamase-producing (ESBL) Escherichia coli and Methicillin-resistant Staphylococcus aureus (MRSA), combined with commercial antibiotics (Penicillin, Ampicillin, Amoxicillin/Clavulanic acid, Cefoxitin, Ciprofloxacin, Cotrimoxazol, Levofloxacin). Microdilution method was used to determine minimum inhibitory concentrations (MICs). The results obtained showed higher synergistic effects against MRSA than against E. coli. Mycena rosea and Fistulina hepatica were the best extracts for synergistic effects against MRSA. The efficiency of Russula delica extract against E. coli 1 (resistant to Ampicillin, Ciprofloxacin and Trimethoprim/Sulfasoxazole) and E. coli 2 (resistant to Amoxicillin/Clavulanic acid and Ampicillin) was higher than that of Leucopaxillus giganteus extract; nevertheless the latter extract exhibited better synergistic effects against ESBL E. coli. Conclusions: This study shows that, similarly to plants, some mushroom extracts can potentiate the action of antibiotics extensively used in clinical practice for Gram-positive or Gram-negative bacteria, with positive action even against multi-resistant bacteria. Significance and Impact of the Study: Mushroom extracts could decrease therapeutic doses of standard antibiotics and reduce microorganism’s resistance to those drugs.

Ganoderma lucidum is one of the most extensively studied mushroom species due to its medicinal properties. It has been used as functional food and as chemopreventer in some countries for thousands of years, and became a popular dietary supplement ingredient in Western countries [1]. Some of its pharmacological properties have been related to antitumour properties, attributed to a wide variety of bioactive components such as polysaccharides, triterpenes, sterols, lectins and some proteins [2,3]. Nevertheless, the bioactive properties of its phenolic compounds have not been studied. The aim of this work was to study the potential antitumor activity of the methanolic extract of this mushroom. This extract of Ganoderma lucidum, collected in Northeast Portugal, was characterized in phenolic compounds, by high performance liquid chromatography coupled to photodiode array detection and mass spectrometry (HPLC-DAD-MS). The extract was further submitted to evaluation of growth inhibitory activity in four human tumour cell lines (MCF-7, NCI-H460, HCT15 and AGS), by the sulforhodamine B assay. The extract presented a moderate growth inhibitory activity in all the cell lines tested (values of GI50 between 93.3±18.1 and 112.6±11.7μg/mL).The following compounds were identified in the extract: p-hydroxybenzoic acid (0.58 ± 0.04 mg/100 g dw), p-coumaric acid (0.38 ± 0.03 mg/100 g dw) and cinnamic acid (0.28 ± 0.03 mg/100 g dw). Future work will elucidate the mechanism of action of the studied extract leading to the observed cell growth inhibition.

Ectomycorrhizal (ECM) symbiosis plays a major role in nutrient cycling and the functioning of forest ecosystems. Trees with well developed ectomycorrhizas are more resistant to environmental stresses such as drought and to biotic stresses such as root pathogens. The establishment of ECM symbiosis is triggered by signals produced by both partners. These signals lead to morphological changes and a complex development of specific structures in both the plant root and the fungus. The development of the ECM fungi, Paxillus involutus and Pisolithus arhizus, in presence and absence of the symbiont – Pinus pinaster- was evaluated, as well as their antioxidant properties and phenolic compounds composition in response to the symbiotic association. ECM fungi grew less in the presence of Pinus pinaster, with Pisolithus arhizus being less affected in growth and thus being more adapted to this association. Protocatechuic acid was found only in Paxillus involutus, while Pinus pinaster roots, both in association and isolated, proved to have other phenolic acids, such as p-hydroxybenzoic and p-coumaric acids. The symbiosis between Paxillus involutus and Pinus pinaster had no major effects on the symbionts, while the association between Pisolithus arhizus and Pinus pinaster seems to generally decrease the antioxidant effects of both symbionts, despite the increase in p-coumaric and cinnamic acids in the ECM fungi.