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There have been growing interests in microalgal biotechnology for the biorefining of bioactive compounds such as carotenoid pigments, ω-3 fatty acids, antioxidants or antimicrobials for sectoral applications in the pharmacology, nutraceutical and cosmetic fields. This study focused on the unicellular marine rhodophyte Porphyridium purpureum CCAP 1380/1 A, which was cultivated via a two-stage batch growth mode for 10 days using hydrogen peroxide (H 2 O 2 ), the phytohormone methyl jasmonate (MJ) and three plant extracts (Passiflora incarnata, Panax ginseng and Valeriana officinalis). The microalgal biomass was then analysed for its protein, phycoerythtin, carbohydrate and pigment composition together with its pigment content and antioxidant activity. Of note, MJ increased the protein and phycoerythtin content (up to 225 µg BSA eq./mg DW and 15 mg/ml, respectively) while both the MJ and H 2 O 2 treatments increased carotenoid pigment yields (β-carotene and zeaxanthin, up to 5 and 4 mg/g, respectively). Carbohydrates were enhanced ∼10 fold by the Valeriana officinalis treatment (up 192 μg starch eq./mg). Overall, neutral lipids and antioxidants were mostly negatively affected by the plant extracts. The greatest antioxidant activity registered was obtained with the H 2 O 2 treatment (15 μmol Trolox eq./g DW with TEAC assay). P. purpureum contains multiple valuable compounds of commercial interest. These results indicate that they can be favorably modulated using specific cultivation regimes and chemical enhancers, thereby facilitating the exploitation of the biomass by applying a suitable co-refinery pipeline., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Abstract: In addition to the implications that this pandemic has had on physical health, there are other circumstances that threaten the mental health of the population, such as lockdown measures to prevent the spread of the virus, uncertainty, and the increase in infections and deaths. For this reason, this study explored indicators of psychological distress in the Argentine population, as well as its relationship with sociodemographic and health variables.Cross-sectional observational study, with data collection from May to August 2020. A total of 1112 people over the age of 18 who responded to various measurement instruments through an online questionnaire participated. A bivariate analysis and logistic regression were carried out in order to determine predictive factors of psychological distress.The data revealed that 60.9% of the sample presented psychological distress. A greater number with this condition was observed in women, apart from younger people, with a greater number of symptoms associated with the disease and with worse self-perceived health. There was no evidence of association between psychological distress and contact with people infected with coronavirus disease 2019 or with material suspicious of being infected.This research provided an overview of the mental health status of a significant population sample in Argentina, months after the onset of the coronavirus disease 2019 pandemic. These findings complement those found in other national and international studies, allowing the accumulation of evidence that states the need to demand to draw attention to the mental health of the population, especially the most vulnerable groups, on behalf of the public authorities., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Microalgae have received growing interest for their capacity to produce bioactive metabolites. This study aimed at characterising the antimicrobial potential of the marine dinoflagellate Amphidinium carterae strain LACW11, isolated from the west of Ireland. Amphidinolides have been identified as cytotoxic polyoxygenated polyketides produced by several Amphidinium species. Phylogenetic inference assigned our strain to Amphidinium carterae subclade III, along with isolates interspersed in different geographic regions. A two-stage extraction and fractionation process of the biomass was carried out. Extracts obtained after stage-1 were tested for bioactivity against bacterial ATCC strains of Staphylococcus aureus , Enterococcus faecalis , Escherichia coli and Pseudomonas aeruginosa . The stage-2 solid phase extraction provided 16 fractions, which were tested against S. aureus and E. faecalis. Fractions I, J and K yielded minimum inhibitory concentrations between 16 μg/mL and 256 μg/mL for both Gram-positive. A targeted metabolomic approach using UHPLC-HRMS/MS analysis applied on fractions G to J evidenced the presence of amphidinol type compounds AM-A, AM-B, AM-22 and a new derivative dehydroAM-A, with characteristic masses of m/z 1361, 1463, 1667 and 1343, respectively. Combining the results of the biological assays with the targeted metabolomic approach, we could conclude that AM-A and the new derivative dehydroAM-A are responsible for the detected antimicrobial bioactivity.

Cellular, inter-organismal and cross kingdom communication via extracellular vesicles (EVs) is intensively studied in basic science with high expectation for a large variety of bio-technological applications. EVs intrinsically possess many attributes of a drug delivery vehicle. Beyond the implications for basic cell biology, academic and industrial interests in EVs have increased in the last few years. Microalgae constitute sustainable and renewable sources of bioactive compounds with a range of sectoral applications, including the formulation of health supplements, cosmetic products and food ingredients. Here we describe a newly discovered subtype of EVs derived from microalgae, which we named nanoalgosomes. We isolated these extracellular nano-objects from cultures of microalgal strains, including the marine photosynthetic chlorophyte Tetraselmis chuii , using differential ultracentrifugation or tangential flow fractionation and focusing on the nanosized small EVs (sEVs). We explore different biochemical and physical properties and we show that nanoalgosomes are efficiently taken up by mammalian cell lines, confirming the cross kingdom communication potential of EVs. This is the first detailed description of such membranous nanovesicles from microalgae. With respect to EVs isolated from other organisms, nanoalgosomes present several advantages in that microalgae are a renewable and sustainable natural source, which could easily be scalable in terms of nanoalgosome production., Competing Interests: The authors report no conflict of interest., (© 2021 The Authors. Journal of Extracellular Vesicles published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.)