Browsing by Author "Monteiro, Diana"
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- Atividade antifúngica da Acacia tortilis e Lactobacillus reuteri em Candida albicansPublication . Brêa, Carlos; Monteiro, Diana; Martins, Tânia; Alves, Maria José; Heleno, Sandrina A.; Ferreira, Isabel C.F.R.O aumento da resistência fúngica a terapias com antimicóticos tem gerado preocupação e como consequência tem sido proposta uma abordagem alternativa para controlar estas infeções, que passa pela utilização de probióticos e produtos naturais no combate a espécies patogénicas. Há um interesse crescente na utilização destes produtos para prevenir e combater infeções vaginais e urogenitais. O Lactobacillus reuteri é um probiótico que produz substâncias antimicrobianas como ácidos orgânicos e etanol bem como bacteriocinas de largo espectro, a reuterina, capazes de inibir a síntese de ADN em agentes patogénicos e remodelar a composição da microbiota comensal no hospedeiro de forma a beneficiar o sistema imunológico e a saúde em geral
- Investigation of olive mill wastewaters treatment by immobilized microalgaePublication . Martins, Bruna da Silva; Monteiro, Diana; Fernandes, ConceiçãoOlive mill wastewater (OMW) is characterized by minimum levels of nitrogen compounds and low pH, as well as very high organic load, due to high levels of phenolic compounds and sugars [1,2]. OMW direct disposal may pollute both, land and aquatic environments [1], therefore is one of the most serious environmental problems in producers countries. Although the two-phase method is a most innovative technique, in Portugal still exist the three-phase process. In this work, immobilized microalgae were tested to treat OMW, in order to reduce phyto-toxicity. From our knowledge it appears that OMW treatment methods with microalgae is a pioneering technique.
- Investigation of olive mill wastewaters treatment by immobilized microalgaePublication . Martins, Bruna da Silva; Monteiro, Diana; Fernandes, ConceiçãoDuring the extraction process of olive oil a large quantity of liquid and solid residues are produced. Nowadays, two-phase and three-phase centrifugation systems are most commonly used. The two-phase centrifugation system reduces the water consumption during the process and practically integrates the three-phase mill wastewater, nevertheless in smaller quantities. The two-phase olive-mill waste presents a slightly acidic pH and a very high content of organic matter, comprising relatively large amounts of lignin, hemicellulose and cellulose, fats, carbohydrates, as well as phenolic compounds [1, 2]. Despite the fact that degradation of olive mill effluents was exhibited in the past [1-3], two-phase olive-mill waste still pose serious problems related with its effective management and safe disposal. Biotreatment of wastes water using living organisms is an environmentally friendly, relatively simple and cost-effective alternative to physico-chemical processes. Previous work was shown that Chlorella vulgaris, a single-cell Chlorophyceae, was the ability to growth in medium supplemented with several plant extracts rich in phenolic compounds [5]. Therefore, the aim of this work was evaluate the ability of immobilized C. vulgaris to remove phenolics compounds from olive mill wastewaters and assess their potential bioremediation by evaluating toxicity on final treated effluent.
- Modelação matemática para identificar o valor de T-ScorePublication . Monteiro, Diana; Pereira, Ana I.; Baptista, Maria do Carmo; Fonseca, E.M.M.A osteoporose é uma patologia esquelética sistémica, caracterizada pela diminuição da massa óssea, provocando uma diminuição da resistência do osso e, consequentemente um aumento do risco de fraturas no indivíduo. Neste estudo pretende-se prever o valor que permite determinar se um paciente tem ou não osteoporose, denominado de T-Score. Normalmente este valor é obtido através de um exame de densitometria óssea, a absorciometria de raios-X de dupla energia (DEXA). Além disso, pretendeu-se converter os valores de T-Score e a densidade mineral óssea (DMO) (ou bone mineral density - BMD) para os vários equipamentos existentes para este exame. Para finalizar, criou-se um documento PDF com as previsões e as conversões alcançadas.
- Preliminary results of olive mil wastewater treatment by immobilized microalgaePublication . Martins, Bruna da Silva; Monteiro, Diana; Fernandes, ConceiçãoThe olive mill wastewater (OMW) is the principal industry residue extraction of olive oil. Generally is characterized by very high organic load, due to high levels of phenolic compounds and sugars, and have minimum levels of nitrogen compounds and low pH. A variety of biological processes and microorganisms have been tested to treat OMW, including bacteria, yeasts and fungi, where the effectiveness in reducing the toxicity varies greatly. Taking this into account, the aim of this work is to assess the potential of microalgae in the decrease of phenolic compounds in OMW. For this purpose, the effect of immobilized Chlorella vulgaris in OMW biotreatments has been tested in batch cultures. The effectiveness of the process has also been assessed by phytotoxicity, in germination trials of Lactuca sativa. Biotreatments have been performed with OMW dilutions of 35%, 50% and 60%. Results showed that C. vulgaris has the ability to remove phenolic compounds, achieving a final Phenolic Loss Index (PLI) of 73%. Regarding the phytotoxicity after biotreatment we can conclude that microalgae can reduce the toxicity of olive mill wastewaters also having the ability to degrade the phenolic compounds that inhibit the germination and growth of Lactuca sativa. Furthermore, the algae biomass obtained in this process could be valorized in other applications.