Browsing by Author "Costa, Cristina"
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- Agrocybe cylindracea bio-residues: a sustainable source of ergosterol-rich bioactive extractsPublication . Silva, Ana Rita; Pinela, José; Caleja, Cristina; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Barros, Lillian; Ferreira, Isabel C.F.R.The world production of edible mushrooms has increased more than 30‐fold since 1978 and, on average, each customer consumes 5 kg of mushrooms per year [1]. Depending on the dimension of the mushroom industry, the amount of obtained by-products may range from 20 to 35% in weight of fresh mushroom [2]. Indeed, 38% of the 90 million tonnes of food waste produced by the European Union every year has its origin in the food manufacturing sector [3]. However, there are several strategies of transforming these wastes into high value-added products based on the cascade use principle, and this is exactly what the MicoBioExtract project aims to perform. Thus, the bio-residues of a popular edible mushroom in southern Europe, Agrocybe cylindracea, were studied as a sustainable source of bioactive extracts [4]. Ergosterol has been reported to be one of the most important compounds, contributing to the health-promoting benefits, associated with mushrooms’ consumption [2]. Its extraction was performed using a heat-assisted technique and applying the response surface methodology, in order to optimize the combined effects of the variables time, temperature and solvent percentage, using a circumscribed central composite design with 16 independent combinations and 4 replicated centre points. At the optimum condition predicted by the model, the bioactivity of the extract was tested, evaluating the antioxidant (TBARS assay) and cytotoxic (in a porcine liver primary cell culture, PLP2) activities. The results obtained from the optimization study showed a significant interaction between temperature and extraction time, with an 8.24% extraction yield. The global optimum condition for ergosterol extraction predicted by the model was 150 min at 90 °C, with 329 mg of ergosterol per 100 g of dry weight sample. Regarding the bioactive potential, namely the antioxidant activity, this extract was capable of preventing the formation of malondialdehyde, a secondary product of lipid peroxidation in the TBARS assay. Concerning the cytotoxicity of the extracts against the PLP2 cell line, the results showed no significant cytotoxic effect, with GI50 values higher than 400 μg/mL. Thus, the extraction of molecules with a high nutritional and bioactive value from mushroom bio-residues and the goal to incorporate them in functional foods and nutraceuticals could boost the circular bio-economy, and help developing strategies towards promoting sustainability.
- Agrocybe cylindracea bio-residues: a sustainable source of ergosterol-rich bioactive extractsPublication . Silva, Ana Rita; Pinela, José; Caleja, Cristina; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Barros, Lillian; Ferreira, Isabel C.F.R.The world production of edible mushrooms has increased more than 30‐fold since 1978 and, on average, each customer consumes 5 kg of mushrooms per year [1]. Depending on the dimension of the mushroom industry, the amount of obtained by-products may range from 20 to 35% in weight of fresh mushroom [2]. Indeed, 38% of the 90 million tonnes of food waste produced by the European Union every year has its origin in the food manufacturing sector [3]. However, there are several strategies of transforming these wastes into high value-added products based on the cascade use principle, and this is exactly what the MicoBioExtract project aims to perform. Thus, the bio-residues of a popular edible mushroom in southern Europe, Agrocybe cylindracea, were studied as a sustainable source of bioactive extracts [4]. Ergosterol has been reported to be one of the most important compounds, contributing to the health-promoting benefits, associated with mushrooms’ consumption [2]. Its extraction was performed using a heat-assisted technique and applying the response surface methodology, in order to optimize the combined effects of the variables time, temperature and solvent percentage, using a circumscribed central composite design with 16 independent combinations and 4 replicated centre points. At the optimum condition predicted by the model, the bioactivity of the extract was tested, evaluating the antioxidant (TBARS assay) and cytotoxic (in a porcine liver primary cell culture, PLP2) activities. The results obtained from the optimization study showed a significant interaction between temperature and extraction time, with an 8.24% extraction yield. The global optimum condition for ergosterol extraction predicted by the model was 150 min at 90 °C, with 329 mg of ergosterol per 100 g of dry weight sample. Regarding the bioactive potential, namely the antioxidant activity, this extract was capable of preventing the formation of malondialdehyde, a secondary product of lipid peroxidation in the TBARS assay. Concerning the cytotoxicity of the extracts against the PLP2 cell line, the results showed no significant cytotoxic effect, with GI50 values higher than 400 μg/mL. Thus, the extraction of molecules with a high nutritional and bioactive value from mushroom bio-residues and the goal to incorporate them in functional foods and nutraceuticals could boost the circular bio-economy, and help developing strategies towards promoting sustainability.
- Enhanced extraction of ergosterol from Pleurotus ostreatus using response surface methodology (RSM)Publication . Taofiq, Oludemi; Heleno, Sandrina A.; Carocho, Márcio; Costa, Cristina; Prieto Lage, Miguel A.; Barros, Joana; Ferreira, Inês; Nunes, João; Barros, Lillian; Ferreira, Isabel C.F.R.Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm., is one of the most widely consumed mushrooms in the world with interesting health-promoting benefits, mainly due to its richness in several bioactive compounds [1]. Mushrooms produce ergosterol as one of their main sterols, which has been considered a contributor to their anti-inflammatory, antioxidant, and antitumor properties [2]. Obtaining an ergosterol enriched extract depends on different variables, such as the extraction method, solvent type, temperature, extraction time, and the solid-liquid ratio [3]. Therefore, it is essential to define the main variables and relevant response criteria to maximize the extraction yield and purity, combining the economic competitivity. In the present work, response surface methodology (RSM) was applied to optimize a heat assisted extraction system (HAE), combining time (t) and temperature (T) effects, and using a circumscribed central composite design (CCCD) for the recovery of ergosterol from the fruiting bodies of P. ostreatus produced with lignocellulose substract. The obtained responses were the quantification of ergosterol by HPLC-UV (Y1: mg of ergosterol per g of extract residue and Y2: mg of ergosterol per 100 g of dry weight mushroom), and the extraction yield (Y3: %). The CCCD consist of 16 response combinations and 4 centre points. Response surface models were fitted by using the following second order polynomial equation. The results obtained showed a significant interaction between the variables. For all the three responses (Y1, Y2, and Y3), the model successfully explained more than 80% variation in the experimental data (i.e. R2˃8). The individual optimum conditions and responses were as follows; Y1 (10 min, 30°C, 57.6 mg/g), Y2 (150 min, 61°C, 246.3 mg/100 g dw), and Y3 (10 min, 80.9°C, 9.3%). The global optimum conditions predicted by the model were: 150 min and 54.3 °C, capable of yielding 7.3 %, 33.3 mg/g and 244.3 mg/100 g dw. The values predicted by the model are in close agreement with the experimental observations with very low residual distribution, proving the validity of the applied model. The results also showed the usefulness of the predictions for future scale up based on the desired responses. The obtained ergosterol enriched extract can be considered as a bioactive ingredient for pharmaceutical, cosmeceutical and nutraceutical purposes.
- Ergosterol rich-extracts from Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm: a comparative study between mushroom and its bio-residuesPublication . Oludemi, Taofiq; Silva, Ana Rita; Costa, Cristina; Prieto Lage, Miguel A.; Barros, Joana; Ferreira, Inês; Nunes, João; Barros, Lillian; Ferreira, Isabel C.F.R.Edible, medicinal, and wild mushrooms are the three major components of the global mushroom industry, recently accounted for US$ 38.13 billion, and expanding at a compound annual growth rate (CAGR) of 7.9% from 2018 to 2026 [1]. Depending on the mushroom industry size, a large amount of bio-residues is generated and often discarded (20 to 35% in weight of fresh mushrooms), even though their content in biomolecules is not necessarily compromised [2]. Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm is one of the most produced edible mushrooms worldwide due to its ability to colonize and degrade a large variety of lignocellulosic substrates [3]. In the present work, P. ostreatus bio-residues (POR) and intact mushrooms (POG) were compared for their ergosterol content. Response Surface Methodology (RSM) was applied using heat-assisted extraction methodology. The combined effect of time (10-150 min) and temperature (30-90°C) was performed using a circumscribed central composite design (CCCD), and the response criteria determined using the HPLC-UV were ergosterol content in mg/g (ergosterol purity) and mg/100g dw (ergosterol extraction yield)
- O gado asinino na área do Parque Natural do Douro Internacional. Razões da sua importância no meio ruralPublication . Samões, Luisa; Barbosa, José Carlos; Costa, CristinaIntegrado nos "Estágios do Instituto da Conservação da Natureza" temos vindo a realizar um trabalho de estudo do gado asinino na área do Parque Natural do Douro Internacional (PNDI). Este trabalho permitiu-nos conhecer, entre outros, o papel social, económico e cultural destes animais no meio rural. Assim, procuramos explicitar as principais razões da sua importância nesta área geográfica. Tido como uma espécie pecuária menor e desde sempre afastado das prioridades pecuárias nacionais, o asinino (Equus asinus) desempenhou, e continua a desempenhar, um papel fundamental na frágil economia das populações rurais das regiões desfavorecidas, como é o caso das abrangidas pela área do PNDI. Sobrevivendo como nenhum outro à mecanização agrícola, ao êxodo e envelhecimento da população rural, graças à sua rusticidade, polivalência e docilidade, não só conseguiu assegurar as tarefas que anteriormente desempenhava, como adquiriu novas funções e demonstra potencialidades para ser explorado de futuro em muitas outras, não sendo, como é habitual julgá-lo, um animal obsoleto e sem préstimo.
- Mastitis diagnosis in dairy goats through somatic cell counts and California mastitis test. Preliminary resultsPublication . Mendonça, Álvaro; Nunes, Mário Armada; Valentim, Ramiro; Correia, Teresa Montenegro; Trigo, Margarida; Maurício, Raimundo; Costa, Cristina; Coelho, AlípioThe aim of this work was to evaluate somatic cell count (SCC) and Californian mastitis test (CMT) reliability as methods to survey mastitis in Serrana goats. Microbiological diagnosis, SCC and CTM were performed on 2028 samples, collected from individual glands during a lactation period. According to results CMT (predictive negative value = 69.5%) may be used as a cheap and practical method for sub clinical mastitis survey in Serrana goats. Decision on SCC use will depend on additional research works, since its values were very high even for bacteriological negative samples.
- Mastitis diagnosis in dairy goats through somatic cell counts and Californian Mastitis Test. Preliminary resultsPublication . Mendonça, Álvaro; Valentim, Ramiro; Nunes, Manuel; Correia, Teresa Montenegro; Trigo, Margarida; Maurício, Raimundo; Costa, Cristina; Coelho, AlípioThe aim of this work was to evaluate somatic cell count (SCC) and Californian mastitis test (CMT) reliability as methods to survey mastitis in Serrana goats. Microbiological diagnosis, SCC and CTM were performed on 2028 samples, collected from individual goat glands during a lactation period. According to results CMT (predictive negative value = 69.5%) may be used as a cheap and practical method for sub clinical mastitis survey in Serrana goats. Decision on SCC use will depend on additional research works, since its values were very high even for bacteriological negative samples.
- Mushrooms bio-residues valorisation: Optimisation of ergosterol extraction using response surface methodologyPublication . Silva, Ana Rita; Oludemi, Taofiq; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Simal-Gandara, Jesus; Barros, Lillian; Ferreira, Isabel C.F.R.The bio-residues of Pleurotus ostreatus, Agrocybe cylindracea, and Pleurotus eryingii were stud-ied as sustainable sources of ergosterol. Its extraction was performed by a heat-assistedextraction technique and optimised using response surface methodology. The responseswere: extraction yield of the residual material (R) from the mushroom bio-residues driedweight (%), the quantification of ergosterol in the M dw (mg E/100 g M dw), and in the R (mgE/g R). The most feasible responses for industrial transference were obtained for P. ostreatusbio-residues, at the optimal conditions of 65.6 min at 30◦C and 43.7 min at 90◦C producing43.72 mg E/g R and 290.90 mg E/100 g M dw, respectively. The model satisfactorily fitted theexperimental data for all responses, thus implying a good agreement between the experi-mental values and those predicted by the model. The study proposes a simple and efficientmethod to produce an ergosterol rich extract from mushroom bio-residues.
- Optimization of ergosterol extraction from Pleurotus mushrooms using response surface methodology (RSM)Publication . Taofiq, Oludemi; Silva, Ana Rita; Costa, Cristina; Prieto Lage, Miguel A.; Barros, Joana; Ferreira, Inês; Nunes, João; Barros, Lillian; Ferreira, Isabel C.F.R.Pleurotus genus represents one of the most widely consumed mushrooms in the world with interesting healthpromoting benefits, mainly due to their richness in several bioactive compounds [1]. Mushrooms produce ergosterol as one of their main sterols, which has been considered a contributor to their anti-inflammatory, antioxidant, and antitumor properties [2]. Obtaining an ergosterol enriched extract depends on different variables, such as the extraction method, solvent type, temperature, extraction time, and the solid-liquid ratio [2]. Therefore, it is essential to define the main variables and relevant response criteria to maximize the extraction yield and purity, taking into account cost functions. In the present work, response surface methodology (RSM) was applied to optimize a heat assisted extraction system (HAE), combining time (t) and temperature (T) effects, and using a circumscribed central composite design (CCCD) for the recovery of ergosterol from the fruiting bodies of P. ostreatus and P. eryngii produced with lignocellulose substrate. Both mushrooms (POG and PEG for P. ostreatus and P. eryngii) and their byproduct (POR and PER for P. ostreatus and P. eryngii) were used in the present work. The obtained responses were the quantification of ergosterol by HPLC-UV (Y1: mg of ergosterol per g of extract residue and Y2: mg of ergosterol per 100 g of dry weight mushroom).
- Optimization of ergosterol extraction from: Pleurotus mushrooms using response surface methodologyPublication . Taofiq, Oludemi; Silva, Ana Rita; Costa, Cristina; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Simal-Gandara, Jesus; Barros, Lillian; Ferreira, Isabel C.F.R.In this study, heat-assisted extraction (HAE) was used to maximize ergosterol extraction from Pleurotus ostreatus (PO) and Pleurotus eryngii (PE) using response surface methodology (RSM). Different temperature (T) and time (t) conditions were applied to understand their influence on the extraction yield (Y1), ergosterol purity in the extracted material (mg g-1 R, Y2) and ergosterol content in the two Pleurotus species (mg per 100 g dw, Y3). A circumscribed central composite design was used to evaluate the interactive effects of extraction variables and the optimal conditions were determined using second-order polynomial mathematical models to describe the responses obtained. In all cases, the predicted responses showed satisfactory fitting between the predicted and experimental values (R2 values >0.8). The global optimum conditions predicted by the models were for PO at T = 54.3 °C and t = 150 min (yielded 7.25%, 33.32 mg E per g R and 244.25 mg E per 100 g dw), while for PE at T = 61.8 °C and t = 150 min (yielded 8.02%, 43.63 mg E per g R and 360.58 mg E per 100 g dw). The obtained results from the two Pleurotus mushroom species using HAE show the possibilities of using them as a production source of enriched extracts in ergosterol.