4 research outputs found
Enzymatic Potential of Filamentous Fungi as a Biological Pretreatment for Acidogenic Fermentation of Coffee Waste
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials (UIDB/50011/2020, UIDP/50011/2020, and LA/P/0006/2020), and the Associate Laboratory for Green Chemistry-LAQV (UIDB/50006/2020 and UIDP/50006/2020). It was financed by national funds through the FCT/MCTES (PIDDAC) and, when appropriate, co-financed by FEDER under the PT2020 Partnership Agreement. Paulo C. Lemos acknowledges the support of FCT/MCTES for contract IF/01054/2014/CP1224/CT0005 and Joana Pereira thanks FCT/MCTES for her Ph.D. grant SFRH/BD/130003/2017.Spent coffee grounds (SCGs) are a promising substrate that can be valorized by biotechnological processes, such as for short-chain organic acid (SCOA) production, but their complex structure implies the application of a pretreatment step to increase their biodegradability. Physicochemical pretreatments are widely studied but have multiple drawbacks. An alternative is the application of biological pretreatments that include using fungi Trametes versicolor and Paecilomyces variotii that naturally can degrade complex substrates such as SCGs. This study intended to compare acidic and basic hydrolysis and supercritical CO 2 extraction with the application of these fungi. The highest concentration of SCOAs, 2.52 gCOD/L, was achieved after the acidification of SCGs pretreated with acid hydrolysis, but a very similar result, 2.44 gCOD/L, was obtained after submerged fermentation of SCGs by T. versicolor. This pretreatment also resulted in the best acidification degree, 48%, a very promising result compared to the 13% obtained with the control, untreated SCGs, highlighting the potential of biological pretreatments.publishersversionpublishe
Mediadores inflamatórios na saliva: associação entre obesidade e doença periodontal
Resumo do poster apresentado no XXXV Congresso Anual SPEMD (Sociedade Portuguesa de Estomatologia e de Medicina Dentária), 9 a 10 de Outubro de 2015, Centro de Congressos Lagoas Park, Lisboa.Sob uma Licença Creative Commons (CC BY-NC-ND 4.0): http://creativecommons.org/licenses/by-nc-nd/4.0
Potencial enzimático de fungos filamentosos em pré-tratamento de borras de café para fermentação acidogénica
With resource depletion and increasing waste production, lignocellulosic
biomass has been studied as biorefinery substrates. Due to its
characteristics, spent coffee grounds (SCG) can be applied in numerous
bioprocesses, such as the production of short-chain organic acids (SCOA).
SCOA are versatile and high valued metabolites that can be produced by
Acidogenic Fermentation (AF) as an alternative to the petrochemical
process. To enhance AF competitiveness is necessary to improve the
hydrolysis rate which can be achieved by enzymatic or chemical
hydrolysis. Enzymatic hydrolysis is considered a more sustainable
alternative. However, enzymes are costly, and consequently, chemical
hydrolysis is the preferred option. Since the used substrate represents a
huge cost in enzyme production, new strategies are necessary. One
possibility is the use of organic wastes. These cheap substrates can
contribute to reducing production costs. In this work, the sole effect of
SCG (0.4 and 1.0% w/v) and the combined effect of SCG and pineapple
peel (PP) (0.4 + 0.2% w/v and 1.0 + 0.4% w/v) were studied as inducers
for enzyme production by Trametes versicolor and Paecilomyces variotii.
In the assay with 0.4% SCG, a laccase activity in T. versicolor of 350 U/L
was recorded. Posteriorly, the enzymatic extracts obtained were used for
SCG pretreatment. To select the best pretreatment for SCOA production,
AF was performed with SCG submitted to different physicochemical and
biological pretreatments. Generally, the main SCOA produced were
acetic, and propionic acids. Acid hydrolysis led to the highest SCOA
concentration (2.52 g COD/L) but submerged fermentation by T.
versicolor led to a similar SCOA concentration (2.44 g COD/L) and
higher acidification degree (48.0%). The obtained results showed the great
potential of T. versicolor enzymes for SCG pretreatment. The experiments
performed allowed us to conclude that SCG can be potentially used as a
laccase inducer and as a substrate for SCOA production, however, these
processes must be optimized to become more competitive.Com a depleção de recursos e o aumento da produção de resíduos, vários
materiais lenhocelulósicos, têm sido estudados como potencias substratos
para biorrefinarias. Pelas suas características, as borras de café (SCG),
podem ser aplicadas em vários processos tais como a produção de ácidos
orgânicos de cadeia curta (SCOA). Os SCOA são metabolitos versáteis e
de elevado valor, que podem ser produzidos por fermentação acidogénica
(AF) em alternativa à produção petroquímica. Para aumentar a
competitividade da AF é necessário melhorar a taxa de hidrólise do
substrato, seja ela química ou enzimática. A hidrólise enzimática é a
escolha mais sustentável, no entanto, as enzimas estão associadas a
elevados custos e, consequentemente, a hidrólise química é a opção
preferida. Dado que os custos de produção de enzimas estão
maioritariamente associados à matéria prima utilizados, têm sido
estudadas novas estratégias. Uma delas é a utilização de resíduos
orgânicos como substratos baratos com o intuito de reduzir os custos de
produção e otimizar os processos. Neste trabalho, estudou-se o efeito
individual de SCG (0.4 e 1.0% w/v) e o efeito combinado de SCG e casca
de ananás (PP) (0.4 + 0.2% w/v e 1.0 + 0.4% w/v) para a produção de
enzimas por Trametes versicolor e Paecilomyces variotii, tendo sido
obtida atividade máxima de lacase 350 U/L no ensaio de T. versicolor com
0.4% (w/v) SCG. Posteriormente, os extratos enzimáticos obtidos foram
utilizados no pré-tratamento de SCG. Realizou-se AF com SCG
submetidas a diferentes pré-tratamentos físico-químicos e biológicos de
modo a selecionar o melhor pré-tratamento para a produção de SCOA. De
uma forma geral, os SCOA maioritariamente produzidos foram os ácidos
acético e propiónico. A maior concentração de SCOA (2.52 g COD/L) foi
obtida com hidrólise ácida, mas a fermentação submersa de T. versicolor
levou a uma concentração similar de SCOA (2.44 g COD/L) e maior grau
de acidificação (48.0%). Os resultados obtidos permitiram concluir que as
SCG têm potencial como indutores e substratos para a produção de lacase
e de SCOA, no entanto estes processos deverão ser otimizados para que
se tornem mais competitivos.Mestrado em Biotecnologi
Pallet labelling and ASN - Advanced Shipping Notification
Relatório do Estágio Curricular do DEMEGI 2001, sob a orientação do Professor J. A. Sarsfield Cabral e Eng. Daniela Lavíni