Search

Your search keyword '"Medeiros, Fábio Gonçalves Macêdo"' showing total 3 results
Start Over Author "Medeiros, Fábio Gonçalves Macêdo" Topic yeast
3 results on '"Medeiros, Fábio Gonçalves Macêdo"'

1. Potential of "coalho" cheese whey as lactose source for β-galactosidase and ethanol co-production by Kluyveromyces spp. yeasts.

Author

de Carvalho, Catherine Teixeira, de Oliveira Júnior, Sérgio Dantas, de Brito Lima, Wildson Bernardino, de Medeiros, Fábio Gonçalves Macêdo, de Sá Leitão, Ana Laura Oliveira, dos Santos, Everaldo Silvino, de Macedo, Gorete Ribeiro, and de Sousa Júnior, Francisco Caninde

Subjects
LACTOSE, WHEY, KLUYVEROMYCES marxianus, YEAST, ETHANOL, CHEESE
Abstract

The present study evaluated the co-production of β-galactosidase and ethanol by Kluyveromyces marxianus ATCC 36907 and Kluyveromyces lactis NRRL Y-8279 using as carbon source the lactose found on "coalho" cheese whey. Cheese whey was subjected to partial deproteinization, and physicochemical parameters were assessed. Cultivations were carried out in an shaker to evaluate two carbon/nitrogen (C:N) ratios. The best C:N ratio (1.5:1) was carried to 1.5-L bioreactor cultivation in order to increase co-production yields. The stability of β-galactosidase was assessed against different temperatures and pH, and in the presence of metal ions. Concerning the co-production of β-galactosidase and ethanol, K. lactis proved to be more efficient in both the C:N ratios, reaching 21.09 U·mL−1 of activity and 7.10 g·L−1 of ethanol in 16 h. This study describes the development of a viable and value-adding biotechnological process using a regional cheese by-product from Northeast Brazil for co-production of biomolecules of industrial interest. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

2. Effects of process variables on fermentation time and vicinal diketones concentration for beer production

Author

Medeiros, Cláudio Dantas, Medeiros, Fábio Gonçalves Macêdo, and Pedrini, Márcia Regina da Silva

Subjects
Pilsen beer, Fermentation, Saccharomyces cerevisiae, Diketones, Yeast
Abstract

High quality market supplying is decisive for the beer industry due to the increasing competition and diversity in the sector. The beer-fermentation step represents 70% of all time spent on industrial beer production and it requires highly rigorous control instrumentation so it is not to become a process’ bottleneck. Numerous by-products are formed during the fermentation step and when they are not under strict control, their excess may turn into unpleasant scent and flavour on the final product. Among the sub products formed during the fermentation stage, total vicinal diketones (diacetyl and 2,3pentanedione) are the main components, since they are limiting for subsequent processing steps, besides having a low perception threshold by the consumer and giving undesirable taste and odor. On this particular work, the effects of three process variables were analysed aiming to reduce vicinal diketones concentration on the final product, and to reduce fermentation time. After yeast acidification, with Phosphoric acid, a 50% increase on cell concentration on the fermentation stage, and 0.5 °C changes on fermentation temperature, the results showed a 38% reduction on fermentation hours and 66.3% reduction on vicinal diketones production over fermentation

Published
2016

3. Efficient stabilisation of curcumin microencapsulated into yeast cells via osmoporation.

Author

de Medeiros, Fábio Gonçalves Macêdo, Dupont, Sebastien, Beney, Laurent, Roudaut, Gaëlle, Hoskin, Roberta Targino, and da Silva Pedrini, Márcia Regina

Subjects
*YEAST, *DIFFERENTIAL scanning calorimetry, *MELTING points, *CURCUMIN, *SACCHAROMYCES cerevisiae
Abstract

This study proposes the investigation of curcumin encapsulation into Saccharomyces cerevisiae cells through osmoporation as an efficient way of increasing curcumin stability. The influence of three process parameters (cell, ethanol and curcumin concentrations) on the encapsulation process was evaluated, and the obtained biocapsules were characterised for physical and photochemical stabilisation. Results showed that encapsulation efficiency was favoured by the increase of cells/curcumin ratio and ethanol concentration up to 60%. Differential scanning calorimetry (DSC) curves revealed that yeast encapsulation delayed the curcumin melting point up to 207 °C. Encapsulated curcumin retained over 80% of antioxidant activity after thermal treatment (150 °C) and over 70% after a 50-day exposure to artificial light. Photochemical stability of yeast-encapsulated curcumin was increased by 5.7-fold, and half-life time reached 181 days under illumination conditions. Overall, osmoporation-produced yeast biocapsules confirmed the versatility of osmoporation as an encapsulation technique and successfully improved curcumin stability. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results