Produção de lipase a partir de Candida rugosa NRRL Y-95 utilizando meio de cultura contendo resíduos agroindustriais

As lipases (E.C. 3.1.1.3) são um grupo de enzimas capazes de catalisar a hidrólise da ligação éster de triacilgliceróis, gerando ácidos graxos livres e glicerol. As lipases microbianas são muito utilizadas nas aplicações industriais nas áreas de alimentos, síntese orgânica e farmacêutica. Neste trabalho, visando à produção de lipase a partir da levedura Candida rugosa foram utilizados meios de cultura alternativos compostos por melaço, milhocina e águas russas. As fermentações foram conduzidas em agitador rotatório a 30 °C e 170 rpm. Testaram-se quatro meios contendo diferentes combinações dos resíduos acima mencionados. O meio contendo melaço 10 g/L, milhocina 4 g/L e águas russas 1,0 %(v/v) foi o que propiciou a produção de enzima com maior atividade intracelular 269 ± 10 U/L frente ao substrato pNFL (p-nitrofenil laurato). Esses resultados demonstram que o referido meio alternativo contendo resíduos agroindustriais é adequado para a produção de lipase

Proposta para automatizar o mapa de telefonema interurbano para a Embrapa.

O objetivo deste trabalho é descrever uma proposta de Mapas de Telefonemas Interurbanos (MTIs) automatizada, a qual foi implementada com sucesso na Embrapa Informática Agropecuária e pode, com algumas adaptações, servir para outras unidades da Embrapa usarem.bitstream/CNPTIA/9873/1/comuntec19.pdfAcesso em: 29 maio 2008

Monitoring fructooligossacharides production using Aspergillus aculeatus by HPLC ELSD

Fructooligosaccharides (FOS) are present in plants and fruits at low concentrations, thus their extraction from natural sources may not be economically viable for a large scale industrial application. Therefore, FOS production by fermentation using fungi can be an alternative. In this work, FOS were produced using Aspergillus aculeatus at different sucrose initial concentrations (88 to 265 g/L) and at temperatures from 22 to 32ºC. FOS production was monitored by HPLC-ELSD, allowing to confirm that the initial sucrose concentration significantly influenced biomass growth (a maximum value of 16 ± 2 g was achieved) although it did not significantly affect the maximum FOS yield (amount of FOS produced per initial sucrose) obtained, which varied from 51 to 59 g/g) obtained, which varied from 51 to 59 g/g. Finally, the preliminary results enabled verifying that depending on the fermentation conditions, slightly different FOS production profiles were obtained (Figure 1), revealing differences in the individual FOS concentrations (i.e., 1-kestose, nystose and fructofuranosylnystose), which could be of interest since it has been reported that the beneficial health effects of FOS may depend on the relative FOS composition.This work was also financially supported by Project POCI-01–0145-FEDER-006984–Associate Laboratory LSRE-LCM, UID/AGR/00690/2013 –CIMO and UID/BIO/04469/2013 funded by FEDER - Fundo Europeu de Desenvolvimento Regional through COMPETE2020-Programa Operacional Competitividade e Internacionalização (POCI) – and by national funds through FCT - Fundação para a Ciência e a Tecnologia, Portugal.info:eu-repo/semantics/publishedVersio

Prediction of drug targets in human pathogens

The identification of new and druggable targets in bacteria is a critical endeavour in pharmaceutical research of novel antibiotics to fight infectious agents. The rapid emergence of resistant bacteria makes today's antibiotics more and more ineffective, consequently increasing the need for new pharmacological targets and novel classes of antibacterial drugs. A new model that combines the singular value decomposition technique with biological filters comprised of a set of protein properties associated with bacterial drug targets and similarity to protein-coding essential genes of E. coli has been developed to predict potential drug targets in the Enterobacteriaceae family [1]. This model identified 99 potential target proteins amongst the studied bacterial family, exhibiting eight different functions that suggest that the disruption of the activities of these proteins is critical for cells. Out of these candidates, one was selected for target confirmation. To find target modulators, receptor-based pharmacophore hypotheses were built and used in the screening of a virtual library of compounds. Postscreening filters were based on physicochemical and topological similarity to known Gram-negative antibiotics and applied to the retrieved compounds. Screening hits passing all filters were docked into the proteins catalytic groove and 15 of the most promising compounds were purchased from their chemical vendors to be experimentally tested in vitro. To the best of our knowledge, this is the first attempt to rationalize the search of compounds to probe the relevance of this candidate as a new pharmacological target

In vitro fermentation of raffinose to unravel its potential as prebiotic ingredient

Supplementary data to this article can be found online athttps://doi.org/10.1016/j.lwt.2020.109322.Until now the prebiotic potential of pure trisaccharide raffinose on human health assessed through high-throughput sequencing remains poorly investigated. In this work, an in vitro model using human fecal inocula of two healthy volunteers (D1 and D2) was used to study the prebiotic potential of raffinose and compare it with the well-stablished and commercial prebiotic lactulose. The intestinal microbiota showed preference for raffinose as substrate showing the highest consumption value at 48h (96.0±0.9% D1 and 95.3±0.7% D2). The fermentation of raffinose decreased the medium pH, the ammonia concentration and the relative amount of Proteobacteria, while increasing the total production of lactate and short chain fatty acids (129.9±2.6mmol/L D1 and 179.6±0.6mmol/L D2), CO2 (10.8±0.8 mmol/Lmedium D1 and 5.2±0.3 mmol/Lmedium D2) and the relative amount of Bifidobacterium and Lactobacillus. This study suggests that raffinose holds potential functional properties for human health.CA an BBC acknowledge her grants (UMINHO/BPD/4/2019 and SFRH/BD/132324/2017) from Portuguese Foundation for Science andTechnology (FCT). The study receivedfinancial support from FCT underthe scope of the strategic funding of UID/BIO/04469/2020 unit;COMPETE 2020 (POCI-01-0145-FEDER-006684), through nationalfunds and where applicable co-financed by the FEDER, within thePT2020 Partnership Agreement; the Projects FoSynBio (POCI-01-0145-FEDER-029549) and NewFood–Food Technologies Valorization(NORTE-324 01-0246-FEDER-000043). The authors also acknowledgeBioTecNorte operation (NORTE-01-0145-FEDER-000004) funded bythe European Regional Development Fund under the scope ofNorte2020 -Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Sustainable lipase production by Diutina rugosa NRRL Y-95 through a combined use of agro-industrial residues as feedstock

The potential use of alternative culture media towards the development of a sustainable bioprocess to produce lipases by Diutina rugosa is clearly demonstrated. First, a synthetic medium containing glucose, peptone, yeast extract, oleic acid, and ammonium sulfate was proposed, with lipase activity of 143 U/L. Then, alternative culture media formulated with agro-industrial residues, such as molasses, corn steep liquor (CSL), and olive mill waste (OMW), were investigated. An experimental design was conducted, and only CSL concentration was found to have a positive effect in lipase production. The highest lipase activity (561 U/L) was produced on a mixture of molasses (5 g/L), CSL (6 g/L), OMW (0.5\\% v/v), 0.5 g/L of ammonium sulfate, and 3 g/L of peptone at 24 h of cultivation. Lipase production was also carried out in a 1-L bioreactor leading to a slightly higher lipase activity at 24 h of cultivation. The semi-purified enzyme exhibits an optimum temperature and pH of 40 \textdegreeC and 7.0, respectively. Finally, the media cost per unit of lipase produced (UPC) was influenced by the medium components, specially by the inducer used. The lowest UPC was obtained when the agro-industrial residues were combined and used at the improved concentrations.The study is funded by CAPES, CNPq, and FUNCAP (from Brazil) for the financial support that made this work possible. In addition, the study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, the BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte, and the Project LIGNOZYMES (POCI-01-0145- FEDER-029773).info:eu-repo/semantics/publishedVersio

Designing a functional rice muffin formulated with prebiotic oligosaccharides and sugar reduction

Innovation of pastry products towards higher nutritional and commercial value remains a challenge to the growing field of healthy food. In this study, the prebiotic supplementation and sugar reduction were explored in a widely consumed pastry product with a low level of innovation. The prebiotic potential of commercial agave inulin and galacto-oligosaccharides (GOS) was evaluated and compared by an in vitro model using human fecal inocula. Rice muffins containing 100% of sugar or 75% of sugar supplemented with 0.8% GOS were produced and compared with commercial rice muffins regarding their physical and textural properties. GOS fermentation led to the highest production of lactate and short-chain fatty acids, besides the most significant reduction of the final pH value and of the ammonia and methane production. Inulin presented a higher selectivity towards Lactobacillaceae (51 ± 1% of all), while GOS are more efficient to stimulate Bifidobacteriaceae growth (65 ± 7% of all).This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte; COMPETE 2020 (POCI-01-0145-FEDER-006684), FoSynBio (POCI-01-0145-FEDER-029549) and NewFood (NORTE-01-0246-FEDER000043). CA and BBC acknowledge their grants (UMINHO/BPD/4/2019 and SFRH/BD/132324/2017) from FCT. RM acknowledges the financial support to the Xunta de Galicia and FEDER by the project (EDD431B 2019/01).info:eu-repo/semantics/publishedVersio

The effect of salts on the liquid–liquid phase equilibria of PEG600 + salt aqueous two-phase systems

Six new ATPSs were prepared by combining polyethylene glycol PEG600 with potassium citrate, dipotassium hydrogen phosphate, sodium formate, potassium formate, sodium sulfate, and lithium sulfate. Complete phase diagrams, including the binodal curve and three tie-lines, were determined at 23 °C. The experimental data obtained for the binodal curve were successfully adjusted to the Merchuk equation, and the reliability of tie-line data was confirmed using the equations suggested by Othmer–Tobias and Bancroft. The ability of each ion to induce ATPS formation was investigated. Na+ proved to be more effective in ATPS formation than K+ and Li+. For potassium salts, the order observed for the effectiveness of the anions was: HPO42– > C6H5O73– > HCO2–. Regarding the sodium salts, it was found that SO42– is clearly more effective than HCO2–. The position of the ions in the Hofmeister series and their free energy of hydration (ΔGhyd) were used to explain the ability of the ions to induce PEG salting-out. Furthermore, the effective excluded volume (EEV) of the salts was determined and the following order was found: Na2SO4 > K2HPO4 > Li2SO4 > K3C6H5O7 > NaCHO2 > KCHO2. Similar order was obtained when analyzing the size of the heterogeneous regions, suggesting the practical use of EEV as a comparison parameter between different ATPSs.This work is partially supported by project PEst-C/EQB/LA0020/2011, financed by FEDER through COMPETE-Programa Operacional Factores de Competitividade and by FCT-Fundacao para a Ciencia e a Tecnologia. Sara Silverio acknowledges her Ph.D. grant from FCT (SFRH/BD/43439/2008)