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- Ionic Liquids Synthesis – MethodologiesPublication . Ferraz, Ricardo; Prudêncio, Cristina; Vieira, Mónica; Fernandes, Rúben; Noronha, João Paulo; Petrovski, ZeljkoIonic Liquids (IL) are salts with at least one organic cation. The term “Ionic Liquid” has been restricted to salts with melting point below 100° C [1]. In the recent years, (ILs) have gained popularity in science and technology. The large number of possible cation/ anion combinations allows a great variety of tunable interactions; also their unique properties and characteristics make it a promising and an attractive to work with in several fields. However, how ILs are produced? This editorial pretends to make a brief commentary of some of the main methodologies of ILs synthesis
- Evaluation of valproic acid toxicity in duckweed, Lemna minorPublication . Machado, Beatriz; Prudêncio, Cristina; Ferraz, Ricardo; Barros, PiedadeIn the last years the contamination of water caused by drugs has increased significantly. The main cause is the increase of the number and quantities of drugs that is being used. Many of these compounds cannot be removed effectively by wastewater treatment plants. This problem affects the water cycle and, consequently, all the environment as well as the human health, so it is important to find new methods that can help the removal of drugs from the water. This research is aimed to understand the influence of different concentrations of valproic acid on the growth of the duckweed Lemna minor. After 7 days of exposure it was analysed the number of fronds, the length of the root and the chlorophylls content. The chlorophylls of the Lemna minor samples were analysed by spectrophotometry. The number of fronds was influenced by the concentration of valproic acid. The higher concentrations (0,1 mg/mL; 0,05 mg/mL; 0,025 mg/mL) showed an inhibitory effect while the lower concentrations (0,005 mg/mL; 0,0001 mg/mL) showed a stimulating effect. Relative to the control, the number of fronds was lower in the higher concentrations and higher in the lower concentrations. The root length was affected in all the concentrations. Comparative to the control the higher concentrations presented a diminution of the root’s length while the higher ones had an increase. Like the other parameters the concentration of chlorophylls was affected in all the samples. In the higher concentrations (0,1 mg/mL; 0,05 mg/mL; 0,025 mg/mL) the quantity was lower, comparatively to the control, and in the lower ones (0,01 mg/mL; 0,005 mg/mL; 0,0001 mg/mL) it was higher. In general, the valproic acid influenced all the parameters evaluated: number of fronds, length of the root and concentration of chlorophylls. In the higher concentrations it is notable an inhibitory effect while the lower concentrations have a stimulating one.
- Antitumor Activity of Ionic Liquids Based on AmpicillinPublication . Ferraz, Ricardo; Costa-Rodrigues, Joao; Fernandes, Maria H.; Santos, Miguel M.; Marrucho, Isabel M.; Rebelo, Luís Paulo N.; Prudêncio, Cristina; Noronha, João Paulo; Petrovski, Željko; Branco, Luís C.Significant antiproliferative effects against various tumor cell lines were observed with novel ampicillin salts as ionic liquids. The combination of anionic ampicillin with appropriate ammonium, imidazolium, phosphonium, and pyridinium cations yielded active pharmaceutical ingredient ionic liquids (API-ILs) that show potent antiproliferative activities against five different human cancer cell lines: T47D (breast), PC3 (prostate), HepG2 (liver), MG63 (osteosarcoma), and RKO (colon). Some API-ILs showed IC50 values between 5 and 42 nm, activities that stand in dramatic contrast to the negligible cytotoxic activity level shown by the ampicillin sodium salt. Moreover, very low cytotoxicity against two primary cell lines—skin (SF) and gingival fibroblasts (GF)—indicates that the majority of these API-ILs are nontoxic to normal human cell lines. The most promising combination of antitumor activity and low toxicity toward healthy cells was observed for the 1-hydroxyethyl-3-methylimidazolium–ampicillin pair ([C2OHMIM][Amp]), making this the most suitable lead API-IL for future studies.
- New ionic liquids and salts derived from β-Lactam antibioticsPublication . Ferraz, Ricardo; Branco, Luís; Marrucho, Isabel; Fernandes, Rúben; Prudêncio, Cristina; Noronha, João Paulo; Petrovski, ZeljkoIn recent years ionic liquids (ILs) have been increasing the popularity and the number of applications. Ionic liquids were used mainly as solvent in organic synthesis, but in recent years they are also used in analytical chemistry, separation chemistry and material science. Additional to significant developments in their chemical properties and applications, ionic liquids are now bringing unexpected opportunities at the interface of chemistry with the life sciences. Ionic liquids (ILs) are currently defined as salts that are composed solely of cations and anions which melt below 100ºC. Our goal in this work is to explore the dual activity of the ionic liquids, due to the presence of two different ions, an anion with bacterial activity as β-lactam antibiotics and different kinds of cations. In this work the anions of ILs and salts were derived from three different antibiotics: ampicillin, penicillin and amoxicillin. The cations were derived from substituted ammonium, phosphonium pyridinium and methylimidazolium salts, such as: tetraethyl ammonium, trihexiltetradecilphosphonium, cetylpyridinium, choline (an essential nutrient), 1-ethyl-3-methylimidazolium, and 1-ethanol-3-methyl imidazolium structures. Commercial ammonium and phosponium halogen salts were first transformed into hydroxides on ionic exchange column (Amberlite IRA-400) in methanol. The prepared hydroxides were then neutralized with β-lactam antibiotics. After crystallization we obtained pure ILs and salts containing β-lactam antibiotics. This work presents a novel method for preparation of new salts of antibiotics with low melting point and their chemistry and microbiological characterization.
- Steroselective synthesis of imidazolidin-4-ones from α-amino amides of the antimalarial primaquine and substituted benzaldehydesPublication . Ferraz, Ricardo; Gomes, José R. B.; Passo, Joana; Oliveira, Eliandre; Moreira, Rui; Gomes, PaulaImidazolidin-4-ones are commonly employed as skeletal modifications in bioactive oligopeptides, either as proline surrogates or for protection of the N-terminal amino acid against aminopeptidase-catalysed hydrolysis . We have been working on the synthesis of imidazolidin-4-ones of the antimalarial primaquine , through acylation of primaquine with an α-amino acid and subsequent reaction of the resulting α-aminoamide with a ketone or aldehyde. Thus, when using racemic primaquine, an optically pure chiral α-amino acid and an aldehyde as starting materials, four imidazolidin-4-one diastereomers are to be expected (Scheme 1). However, we have recently observed that imidazolidin-4-one synthesis was stereoselective when 2-carboxybenzaldehyde (2CBA)* was used, as only two diastereomers were produced2. Computational studies have shown that the imine formed prior to ring closure had, for structures derived from 2CBA, a quasi-cyclic rigid structure2. This rigid conformation is stabilized by an intramolecular hydrogen bond involving the C=O oxygen atom of the 2-carboxyl substituent in 2CBA and the N-H group of the α-amino amide moiety2. These findings led us to postulate that the 2-carbonyl substituent in the benzaldehyde moiety was the key for the stereoselective synthesis of the imidazolidin-4-ones2.
- Use of agricultural wastes to design natural products for the prevention of cardiovascular diseasesPublication . Costa, Mariana; Grosso, Clara; Ramalhosa, Maria João; Ferraz, Ricardo; Soares, CristinaCardiovascular diseases (CVDs), or risk factors for CVD, such as diabetes, hypertension and hypercholesterolemia, are the leading cause of death worldwide. Therefore, the use of agricultural by-products as a source of functional ingredients, particularly those from crop plants, has received significant interest. For example, the banana (Musa spp.) is a common food crop worldwide and is the primary production on Madeira Island in Portugal. In this work, banana peels and puree were incorporated into sweet food products as butter and sugar substitutes, enhancing the nutritional content. The results show that the final product’s dietary fibre and phenolic content increased, while the lipidic and total sugar content decreased. The obtained results show that banana peels have a great potential to be developed into beneficial functional foods and nutraceuticals.
- Estudo de novos compostos sintéticos para o tratamento do cancro da mamaPublication . Magalhães, Ângela; Vieira, Filipa Quintela; Vieira, Mónica; Ferraz, Ricardo; Prudêncio, Cristina; Jerónimo, Carmen; Silva, ReginaO cancro da mama (CaM) apesar dos avanços no tratamento e deteção precoce desta neoplasia, permanece como uma das principais causas de morte por cancro nas mulheres devido à progressão e disseminação sistémica. Cerca de 80% dos CaM invasivos são positivos para o recetor de estrogénios sendo candidatos à terapia de bloqueio. No entanto, 30- 40% das doentes desenvolvem recidiva, evoluindo para um fenótipo hormono-resistente. Nestes estadios, as opções terapêuticas apresentam uma reduzida eficácia. Assim, é importante a descoberta de novos agentes anti-neoplásicos. Os líquidos iónicos e as quinoxalinas são sais orgânicos com potencial anti-tumoral que têm vindo a ser alvo de estudo na indústria farmacêutica devido às suas propriedades medicinais e composição flexível no caso dos líquidos iónicos.
- Cyanobacteria for skin care and cosmeceutical formulationsPublication . Melo, Luísa; Morone, Janaína; Silva, Margarida; Ferraz, Ricardo; Martins, RosárioSkin acts as a barrier from external stimulus such as pollutants and ultraviolet radiation. Disturbs in the skin are involved in skin aging, which mostly results on a thinner epidermis, dryness, wrinkles, and loss of elasticity. Synthetic ingredients in cosmetics are known to be more toxic and to cause negative impact on the environment. In a society increasingly worried with human and environment health, natural skin care products gain special attention and boosted the search for natural sources. Due to the production of bioactive compounds, cyanobacteria emerged as an excellent source for cosmetic ingredients. Cyanobacteria strains of CIIMAR culture collection (LEGE-CC) have already proven to be interesting for cosmetic purposes [1,2]. In this project we aimed to evaluate the potential of four LEGE-CC cyanobacteria strains for skin care purposes. The cytotoxicity of acetonic and aqueous extracts was evaluated in keratinocytes (HaCAT), fibroblasts (3T3L1) and endothelial cells (hCMEC/D3) along with the total phenolic content and antioxidant properties. Cytotoxic assays revealed toxicity of acetonic extracts to keratinocytes in the higher concentrations tested. Aqueous extracts revealed low or non-cytotoxicity. Mainly in low concentrations of extracts, cellular proliferation was registered. Aqueous extracts from strain JM/RS021A and acetone extracts from strain JM/RS035B revealed higher values for total phenolic compounds. The acetone extracts of strain JM/RS021A showed the greatest scavenging activity values on the DPPH assay.
- Repurposing antiplasmodial leads for cancer: Exploring the antiproliferative effects of N-cinnamoyl-aminoacridinesPublication . Fonte, Mélanie; Rôla, Catarina; Santana, Sofia; Ferraz, Ricardo; Prudêncio, Miguel; Almeida, Joana; Ferraz, Ricardo; Prudêncio, Cristina; Teixeira, Cátia; Gomes, PaulaDrug repurposing and rescuing have been widely explored as cost-effective approaches to expand the portfolio of chemotherapeutic agents. Based on the reported antitumor properties of both trans-cinnamic acids and quinacrine, an antimalarial aminoacridine, we explored the antiproliferative properties of two series of N-cinnamoyl-aminoacridines recently identified as multi-stage antiplasmodial leads. The compounds were evaluated in vitro against three cancer cell lines (MKN-28, Huh-7, and HepG2), and human primary dermal fibroblasts. One of the series displayed highly selective antiproliferative activity in the micromolar range against the three cancer cell lines tested, without any toxicity to non-carcinogenic cells.
- Stalling the course of neurodegenerative diseases: could cyanobacteria constitute a new approach toward therapy?Publication . Ramos, Vitória; Reis, Mariana; Ferreira, Leonor; Silva, Ana Margarida; Ferraz, Ricardo; Vieira, Mónica; Vasconcelos, Vitor; Martins, RosárioNeurodegenerative 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 (PD), Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), and Huntington’s Disease (HD). There are currently no available cures; there are only therapeutic approaches that ameliorate the progression of symptoms, which makes the search for new drugs and therapeutic targets a constant battle. Cyanobacteria are ancient prokaryotic oxygenic phototrophs whose long evolutionary history has resulted in the production of a plethora of biomedically relevant compounds with anti-inflammatory, antioxidant, immunomodulatory, and neuroprotective properties, that can be valuable in this field. This review summarizes the major NDs and their pathophysiology, with a focus on the anti-neurodegenerative properties of cyanobacterial compounds and their main effects.