Phenolic acids are present in our diet in different foods, for example mushrooms. Due to their bioactive properties, phenolic acids are extensively studied and there is evidence of their role in disease prevention. Nevertheless, in vivo, these compounds are metabolized and circulate in the organism as glucuronated, sulphated and methylated metabolites, displaying higher or lower bioactivities. To clarify the importance of the metabolism of phenolic acids, knowledge about the bioactivity of metabolites is extremely important. In this review, chemical features, biosynthesis and bioavailability of phenolic acids are discussed, as well as the chemical and enzymatic synthesis of their metabolites. Finally, metabolite bioactive properties are compared with that of the corresponding parental compounds.

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Cosmetics, like any product containing water and organic/inorganic compounds, require preservation against microbial contamination to guarantee consumer’s safety and to increase their shelf-life. The microbiological safety has as main goal of consumer protection against potentially pathogenic microorganisms, together with the product’s preservation resulting from biological and physicochemical deterioration. This is ensured by chemical, physical, or physicochemical strategies. The most common strategy is based on the application of antimicrobial agents, either by using synthetic or natural compounds, or even multifunctional ingredients. Current validation of a preservation system follow the application of good manufacturing practices (GMPs), the control of the raw material, and the verification of the preservative effect by suitable methodologies, including the challenge test. Among the preservatives described in the positive lists of regulations, there are parabens, isothiasolinone, organic acids, formaldehyde releasers, triclosan, and chlorhexidine. These chemical agents have different mechanisms of antimicrobial action, depending on their chemical structure and functional group’s reactivity. Preservatives act on several cell targets; however, they might present toxic effects to the consumer. Indeed, their use at high concentrations is more effective from the preservation viewpoint being, however, toxic for the consumer, whereas at low concentrations microbial resistance can develop.

Phenolic compounds are natural bioactive molecules found mainly in plant tissues that have shown interesting bioactivities, such as antioxidant, antimicrobial, anti-inflammatory, antiproliferative activities, among others, which has led to great...

This review aims to contribute to the growing knowledge on bioactive (antioxidant, antitumor and antimicrobial) properties of polysaccharides, glycoproteins and polysaccharidic extracts obtained from Ganoderma species. The chemical features were analyzed and related to correspondent bioactivities. ____________________________________________________________________ 2 Research highlightsChemical features of Ganoderma bioactive polysaccharides were discussed.Methods for extraction, isolation and identification were evaluated.Bioactivity of polysaccharidic extracts and purified compounds were discussed.Integration of data allowed deduction of structure-activity relationships.

Abbreviations CATCatalase DAD Diode array detector DPPH 2,2-Diphenyl-1-picrylhydrazyl EC 50Extract concentration providing 50% antioxidant activity or 0.5 absorbance in the reducing power assay FB Fruiting body GAE Gallic acid equivalents GPx Glutathione peroxidase GSH Reduced glutathioneHPLC High-performance liquid chromatography IS Internal standard M Mycelium MMN Melin-Norkans medium MS Mass spectrometry PDA Potato dextrose agar medium PE Polysaccharides equivalents Ph Phenolic extract Ps Polysaccharidic extract RI Refraction index RSA Radical scavenging activity S Spores SOD Superoxide dismutaseTBARS Thiobarbituric acid reactive substances v/v ml/100 ml w/v g/100 ml ABSTRACTGanoderma lucidum is one of the most extensively studied mushrooms due to its medicinal properties. Herein, a systematic study was carried out in order to compare the antioxidant activity of phenolic and polysaccharidic extracts from fruiting body, spores and mycelium, obtained in three different culture media, of G. lucidum from NortheastPortugal. Phenolic extracts were characterized using high-performance liquid chromatography coupled to photodiode array detection, while polysaccharidic extracts were hydrolysed and further characterized using HPLC and refraction index detection.In general, the phenolic extracts (Ph) proved to have higher antioxidant potential than their corresponding polysaccharidic extracts (Ps). Amongst phenolic extracts, FB-Ph provided the highest antioxidant activity (EC 50 ≤ 0.6 mg/ml) and the highest content in total phenolics (~29 mg GAE/g extract) and phenolic acids (p-hydroxybenzoic and pcoumaric acids). S-Ps was the polysaccharidic extract with the best antioxidant activity (EC 50 ≤ 2 mg/ml); nevertheless, the highest levels of total phenolics were obtained in FB-PS (~56 mg GAE/g extract), while the highest levels of total polysaccharides (~14 mg PE/g extract) and individual sugars were observed in mycelia obtained from solid culture media, M-PDA-Ps and M-sMMN-Ps. The free radical scavenging properties, reducing power and lipid peroxidation inhibition of G. lucidum seemed to be correlated with phenolic compounds mostly in a free form, but also linked to polysaccharides.

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Ergosterol, a molecule with high commercial value, is the most abundant mycosterol in Agaricus bisporus L. To replace common conventional extraction techniques (e.g. Soxhlet), the present study reports the optimal ultrasound-assisted extraction conditions for ergosterol. After preliminary tests, the results showed that solvents, time and ultrasound power altered the extraction efficiency. Using response surface methodology, models were developed to investigate the favourable experimental conditions that maximize the extraction efficiency. All statistical criteria demonstrated the validity of the proposed models. Overall, ultrasound-assisted extraction with ethanol at 375 W during 15 min proved to be as efficient as the Soxhlet extraction, yielding 671.5 ± 0.5mg ergosterol/100 g dw. However, with n-hexane extracts with higher purity (mg ergosterol/g extract) were obtained. Finally, it was proposed for the removal of the saponification step, which simplifies the extraction process and makes it more feasible for its industrial transference.