Vitor Vasconcelos

University of Porto | UP · Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR)

Cyanobacteria strains have the potential to produce bioactive compounds that can be used in therapeutics and bioremediation. Therefore, compiling all information about these compounds to consider their value as bioresources for industrial and research applications is essential. In this study, a searchable, updated, curated, and downloadable databas...

Created in BioRender. Essadki, Y. (2024) a01t546/https://BioRender.com

Lichens are symbiotic organisms with unique secondary metabolism. Various metabolites from lichens have shown antimicrobial activity. Nevertheless, very few studies have investigated the antimicrobial potential of the volatile compounds they produce. This study investigates the chemical composition and antimicrobial properties of volatile compounds...

Opuntia is a well-known plant for its folkloric use and nutritional composition. This work aimed to evaluate the physicochemical characteristics, as well as the mineral composition realized by inductively coupled plasma-mass spectrometry (ICP-MS) for cultivated and wild Algerian Opuntia species. The results showed a significant difference in length...

Neurodegenerative diseases are linked to the process of neurodegeneration. This can be caused by several mechanisms, including inflammation and accumulation of reactive oxygen species. Despite their high incidence, there is still no effective treatment or cure for these diseases. Cyanobacteria have been seen as a possible source for new compounds w...

Culture collections such as the Blue Biotechnology and Ecotoxicology Culture Collection (LEGE‐CC) hold approximately 1200 cyanobacterial strains and are critical community resources. However, many isolates in this and other collections have not been described with a polyphasic approach, and this limits further study. Here, we employed a polyphasic...

Cyanobacteria are rich producers of secondary metabolites, excreting some of these to the culture media. However, the exometabolome of cyanobacteria has been poorly studied, and few studies have dwelled on its characterization and bioactivity assessment. In this work, exometabolomes of 56 cyanobacterial strains were characterized by HR-ESI-LC-MS/MS...

In Morocco, red fruit production has thrived, primarily utilizing hydroponic methods to control crops, increase fruit yield and quality, and avoid soil-related problems. However, the irrigation of these expansive hydroponic farms relies heavily on water sourced from dams, many of which are contaminated with Microcystins (MCs). To address this conta...

Cyanobacteria are cosmopolitan organisms; nonetheless, climate change and eutrophication are increasing the occurrence of cyanobacteria blooms (cyanoblooms), thereby raising the risk of cyanotoxins in water sources used for drinking, agriculture, and livestock. This study aimed to determine the presence of cyanobacteria, including toxigenic cyanoba...

Introduction: Biofouling poses a significant economic threat to various marine industries, leading to financial losses that can reach billions of euros annually. This study highlights the urgent need for effective alternatives to traditional antifouling agents, particularly following the global ban on organotin compounds. Material and methods: Stre...

Opuntia plants are abundant but still underexplored edible resources of the Algerian region. This work chemically characterizes extracts of different parts of the fruit of the commercial Opuntia ficus-indica (L.) Mill. and the wild Opuntia stricta (Haw.) Haw. growing in Bejaia, and evaluates their anti-inflammatory potential through different cell...

In this paper we present a bibliographical review of the newly described Brazilian cyanobacterial genera, based on 16S rDNA analysis. Moreover, we discuss their position according to the current classification system of Cyanobacteria. Additionally, in order to comprehend the diversity of Brazilian 16S rDNA sequences deposited in GenBank (NCBI), we...

Metals are important cofactors in the metabolic processes of cyanobacteria, including photosynthesis, cellular respiration, DNA replication, and the biosynthesis of primary and secondary metabolites. In adaptation to the marine environment, cyanobacteria use metallophores to acquire trace metals when necessary as well as to reduce potential toxicit...

Cyanobacterial outgrowths are naturally occurring processes in eutrophic aquatic ecosystems. Furthermore, as a result of climate change and anthropogenic pollution, cyanobacteria harmful algal blooms (CyanoHABs) are expanding worldwide. CyanoHABs are considered a threat to human health and environment due to the production of potent toxic substance...

Cyanobacteria are ancient and prolific microorganisms for which the current knowledge remains limited. The present work constitutes the first report on the presence of the cyanobacteria Tolypothrix sp. LEGE 221228, Nostoc sp. LEGE 221229, Scytonema sp. LEGE 221230 and Drouetiella sp. LEGE 221231 in the volcanic crater lake in Chichonal (Chiapas-Mex...

Microcystins (MCs), natural hepatotoxic compounds produced by cyanobacteria, pose significant risks to water quality, ecosystem stability, and the well-being of animals, plants, and humans when present in elevated concentrations. The escalating contamination of irrigation water with MCs presents a growing threat to terrestrial plants. The customary...

The present study demonstrates the presence of the neurotoxin β-N-methylamino-L-alanine and its cyanobacterial producers in irrigation water and grains of some cereal plants from farmlands irrigated with Nile River water in Egypt. BMAA detected by LC–MS/MS in phytoplankton samples was found at higher concentrations of free form (0.84–11.4 μg L⁻¹) t...

The Tolypotrichaceae is a well-defined family within the filamentous heterocyst-forming cyano-bacteria. However, the morphological and genetic similarity of some of its genera is very high, making the taxonomic assessment and the description of new taxa in this family challenging. Here we describe six strains of Tolypothrix-like cyanobacteria that...

Cyanobacteria are among the oldest organisms colonizing Earth. Their great biodiversity and ability to biosynthesize secondary metabolites through a variety of routes makes them attractive resources for biotechnological applications and drug discovery. In this pioneer study, four filamentous cyanobacteria (Cephalothrix lacustris LEGE 15493, Leptoly...

Metals are important co-factors in the metabolic processes of cyanobacteria including photosynthesis, cellular respiration, DNA replication, and the biosynthesis of primary and secondary metabolites. In adaptation to the marine environment, cyanobacteria use metallophores to acquire trace metals when necessary as well as reduce potential toxicity f...

The venom of cone snails has been proven to be a rich source of bioactive peptides that target a variety of ion channels and receptors. α-Conotoxins (αCtx) interact with nicotinic acetylcholine receptors (nAChRs) and are powerful tools for investigating the structure and function of the various nAChR subtypes. By studying how conotoxins interact wi...

Addressing pressing health concerns, modern medical research seeks to identify new antimicrobials to combat drug resistance, novel molecules for cancer treatment, and antioxidants for inflammation-related diseases. Pisolithus (Basidiomycota) is a ubiquitous and widely distributed fungal genus in forest ecosystems, known for establishing ectomycorrh...

An appealing strategy for finding novel bioactive molecules in Nature consists in exploring underrepresented and -studied microorganisms. Here, we investigated the antimicrobial and tumoral anti-proliferative bioactivities of twenty-three marine and estuarine bacteria of the fascinating phylum Planctomycetota. This was achieved through extraction o...

This study investigates the presence of the neurotoxin β-N-methylamino-L-alanine (BMAA) and its cyanobacterial producers in irrigation water as wells its potential accumulation in nine commonly consumed vegetables from Egyptian farmlands. The HPLC–MS/MS analysis revealed that phytoplankton samples contained higher concentrations of free BMAA (0.6–1...

The interest in microalgae as food in Europe is growing due to its remarkable features that can foster a sustainable economy. The lack of tradition on their use among Europeans is changing and a demand for more sustainable products is increasing. The legal framework from the microalgae stakeholders' point of view has been consistently identified as...

Chemistry identification on cyanotoxins on the most reliable and traditional method on toxic cyanobacteria research, namely on water and bloom matrices. On study a new tool concerning ecosystem net plankton samples (approx. 10 L concentration volume) coupled on chemistry identification on six cyanotoxins (MCLR, MCRR, MCYR, CYN, ATX and SXT) and on...

Coccoid cyanobacteria represent an important part of cyanobacterial freshwater diversity, with many studied strains in public databases identified as Synechococcus. This is a diverse genus, both morphologically and ecologically, with a global distribution. However, many of the so-called Synechococcus-like cyanobacteria strains could represent sever...

Monitoring water supply requires, among other quality indicators, the identification of the cyanobacteria community and taking into account their potential impact in terms of water quality. In this work, cyanobacteria strains were isolated from the Cheffia Reservoir and identified based on morphological features, the 16S rRNA gene, phylogenetic ana...

The taxonomy of cyanobacteria has advanced quickly with the use of molecular methods in combination with well-defined morphological and ecological characters. Using this approach, many taxonomical changes have occurred in the Synechococcales and Oscillatoriales, with the description of new families, genera and species. Here we present the study of...

Simple filamentous cyanobacteria comprise a diverse and polyphyletic group of species, primarily in the orders Leptolyngbyales and Oscillatoriales, that need more sampling to improve their taxonomy. Oceanic islands, such as the Azores archipelago, present unique habitats and biogeographic conditions that harbor an unknown range of diversity of micr...

Neurodegenerative diseases (NDs) are characterized by progressive and irreversible neuronal loss, accompanied by a range of pathological pathways, including aberrant protein aggregation, altered energy metabolism, excitotoxicity, inflammation, and oxidative stress. Some of the most common NDs include Alzheimer’s Disease (AD), Parkinson’s Disease (P...

Although a range of disinfecting formulations is commercially available, hydrogen peroxide is one of the safest chemical agents used for disinfection in aquatic environments. However, its effect on cyanobacterial biofilms is poorly investigated. In this work, biofilm formation by two filamentous cyanobacterial strains was evaluated over seven weeks...

Cyanobacterial exopolysaccharides (EPS) are potential candidates for the production of sustainable biopolymers. Although the bioactive and physicochemical properties of cyanobacterial-based EPS are attractive, their commercial exploitation is limited by the high production costs. Bioprospecting and characterizing novel EPS-producing strains for ind...

Alzheimer’s disease (AD) is well-known among neurodegenerative diseases for the decline of cognitive functions, making overall daily tasks difficult or impossible. The disease prevails as the most common form of dementia and remains without a well-defined etiology. Being considered a disease of multifactorial origin, current targeted treatments hav...

The extensive use of nanomaterials, including titanium dioxide nanoparticles (TiO2 NPs), raises concerns about their persistence in ecosystems. Protecting aquatic ecosystems and ensuring healthy and safe aquaculture products requires the assessment of the potential impacts of NPs on organisms. Here, we study the effects of a sublethal concentration...

Cyanobacteria are a rich source of secondary metabolites, and they have received a great deal of attention due to their applicability in different industrial sectors. Some of these substances are known for their notorious ability to inhibit fungal growth. Such metabolites are very chemically and biologically diverse. They can belong to different ch...

The health risks linked to the consumption of microcystin-accumulating crops have been increasing worldwide in toxic cyanobloom-occurring regions. The bioaccumulation of microcystins (MCs) in agricultural produce at environmentally realistic concentrations is poorly investigated. In this field study, we assessed the health risks of MCs in raw water...

[This corrects the article DOI: 10.3389/fonc.2019.00224.].

The incidence and interest of cyanobacteria are increasing nowadays because they are able to produce some toxic secondary metabolites known as cyanotoxins. Among them, the presence of cylindrospermopsin (CYN) is especially relevant, as it seems to cause damage at different levels in the organisms: the nervous system being the one most recently repo...

Organisms with distinctive biological features and cellular organization constitute the bacterial phylum Planctomycetota. In this study, we formally describe a novel isolate, strain ICT_H6.2T, isolated from sediment samples collected in the brackish environment of the Tagus River estuary (Portugal) using an iChip-based culturing technique. The 16S...

As a producer of pigments with known bioactive potential, cyanobacteria are a great source of active ingredients for cosmetics (i.e., carotenoids and phycobiliproteins). Multiple phases in the cyanobacteria-based bioprocess led to the obtention of these compounds. The marine Cyanobium sp. LEGE 06113 has been proposed as a promising source for pigme...

Cyanobacteria produce a wealth of secondary metabolites. Since these organisms attach fatty acids into molecules in unprecedented ways, cyanobacteria can serve as a novel source for bioactive compounds acting as ligands for Peroxisome Proliferator-Activated Receptors (PPAR). PPARs (PPARα, PPARβ/δ and PPARγ) are ligand-activated nuclear receptors, i...

Cyanobacteria are new sources of value-added compounds but also ubiquitous and harmful microfoulers on marine biofouling. In this work, the isolation and identification of two cyanobacterial strains isolated from Cape Verde and Morocco, as well as their biofilm-forming ability on glass and Perspex under controlled hydrodynamic conditions were perfo...

The reports of cyanobacterial blooms and their impact on ecosystems and human health have increased in the last two decades, becoming of emerging concern for the World Health Organization (WHO). Most of these blooms are non-specific, although a few species showed more dominance, frequently, toxin-producing strains of Microcystis. Likewise, in Cuba,...

Vitamin K isoforms are known as co-factors for the synthesis of blood-clotting proteins, but several other bioactivities were reported. In this work, we isolated a vitamin K1-analogue (OH-PhQ) from the cyanobacterium Tychonema sp. LEGE 07196 with lipid reducing activity. OH-PhQ reduced neutral lipid reservoirs with an EC50 value of 31 μM after 48 h...

Cyanobacteria have long attracted market interest as a source of natural compounds such as pigments with proven bioactivity (carotenoid and phycobiliproteins). The cultivation and extraction processes for such compounds have been developed at different levels, from laboratory trials to photobioreactors on a demonstration scale. Based on this experi...

Nature-based and sustainably sourced cosmetics have been dominating the area of skincare products worldwide. Due to their antioxidant and antiaging properties, compounds from cyanobacteria, such as carotenoids and phycobiliproteins, may replace synthetic ingredients in cosmetic formulations and may be used in products such as sunscreens, skincare c...

The progress of nanotechnology has prompted the development of novel marine antifouling coatings. In this study, the influence of a pristine graphene nanoplatelet (GNP)-modified surface in cyanobacterial biofilm formation was evaluated over a long-term assay using an in vitro platform which mimics the hydrodynamic conditions that prevail in real ma...

The 1,2,3-triazole ring has been gaining increased attention in medicinal chemistry over the past few years since it has been associated with metabolic stability and several biological activities, including antifouling. Therefore, the hybridization of this heterocycle with other pharmacophores which showed ability to prevent marine biofouling can b...

The phylum Planctomycetota is known for having uncommon biological features. Recently, biotechnological applications of its members have started to be explored, namely in the genus Stieleria. Here, we formally describe a novel Stieleria isolate designated as strain ICT_E10.1T, obtained from sediments collected in the Tagus estuary (Portugal). Strai...

An unreported isocoumarin, (3S,4R)-4-hydroxy-6-methoxymellein (2), an undescribed propylpyridinium anthraquinone (4), and an unreported C-glucosyl resorcinol derivative, acetyl carnemycin E (5c), were isolated, together with eight previously reported metabolites including p-hydroxybenzaldehyde (1), 1,3-dimethoxy-8-hydroxy-6-methylanthraquinone (3a)...

Opuntia species are well-known for their use in folk medicine and richness in many bio-active compounds. This study aims to realize a taxonomic study and to evaluate the polyphenols content and antioxidant potential of edible parts of cultivated and wild Opuntia sp. fruits, using different in-vitro bioassays. The phylogenetic analysis confirmed the...