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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.
- 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.
- Ensino e aprendizagem da Bioquímica em Ciências da Saúde: retenção de conhecimentos adquiridos e sucesso académico versus tipo de exame preferido, sua preparação e stress associadoPublication . Prudêncio, Cristina; Fernandes, Rúben; Ferraz, Ricardo; Vieira, Mónica; Fonte, RosáliaNum contexto de reestruturação da formação em Ciências da Saúde baseada em competências, torna-se necessário estudar as diferentes formas de avaliação e o stress que lhe está associado, observando de que forma estas poderão interferir no sucesso académico dos alunos e real aquisição de competências. O objectivo do trabalho foi avaliar estas questões no âmbito da Bioquímica de diferentes cursos de Tecnologias da Saúde. A metodologia foi adaptada de controlled pre-test-postest, e os resultados obtidos apontam para que os alunos que mais estudam, ao longo do ano e não no “sprint final”, parecem possuir menor stress e serem melhor sucedidos.
- New therapeutic approaches based on ionic liquidsPublication . Ferraz, Ricardo; Teixeira, Cátia; Prudêncio, Cristina; Teixeira, Dulce; Vieira, Mónica; Gomes, PaulaIonic liquids (ILs) are currently defined as salts (with at least one organic ion) stable above their melting point. They began to be used mainly as solvents, but quickly drew the attention of the Life Sciences, as some of the characteristics of those compounds may be relevant in therapeutic applications. ILs can show more interesting physicochemical properties at the level of active pharmaceutical ingredients such as water solubility, in addition to the fact that ILs (liquids at room temperature and/or human body temperature) do not present polymorphism, an aspect which often limits the conditions of use and therapeutic efficacy of solid active pharmaceutical ingredients. This line of research seeks, through a careful choice of the ions, to fine-tune some of these properties, and to study the combination of two bioactive molecules that have ionizable groups of opposite charge, forming ionic liquids with a dual therapeutic effect.