Repositório Colecção: CEB - Painéis em Conferências / Posters in ConferencesCEB - Painéis em Conferências / Posters in Conferenceshttps://hdl.handle.net/1822/563662024-03-28T14:41:33Z2024-03-28T14:41:33ZDevelopment of a cost-effective media for biosurfactants production by Pseudomonas aeruginosaBraga, Adelaide CorreiaCardoso, Beatriz Alexandra BatistaFernandes, MargaridaCosta, João Manuel RainhaSilva, CarlaRodrigues, L. R.https://hdl.handle.net/1822/888292024-02-19T11:54:03Z2024-02-19T11:54:02ZTítulo: Development of a cost-effective media for biosurfactants production by Pseudomonas aeruginosa
Autor: Braga, Adelaide Correia; Cardoso, Beatriz Alexandra Batista; Fernandes, Margarida; Costa, João Manuel Rainha; Silva, Carla; Rodrigues, L. R.
Resumo: In the last years, the textile industry has shown a growing interest in biosurfactants due to their
biocompatibility , biodegradability , and versatility at various pH and temperature ranges . These
compounds have found applications as softeners, wetting agents, lubricants, foam stabilizers, and
even in the scouring of wool. This study aims to develop an economically efficient medium for
biosurfactant production by Pseudomonas aeruginosa #112. Firstly , waste cooking oils after
treatment (WCOT), a residue rich in lipids, was evaluated as an inducer of biosurfactants
production . Different concentrations of these substrates (1, 2.5, 5, and 10 % w/v) were tested,
and glucose was used as a carbon source. In the experiments with 1 % of WCOT it was observed
a significant (p 0.05) reduction in the surface tension from 48.4 mN/m to 34.8 mN/m, suggesting
the biosurfactant production . Furthermore , rice husk (RH) and vine pruning (VP) residues were
identified as alternative carbon sources for biosurfactants production, when combined with WCOT
. Both residues are rich in cellulose, which can be broken down into free glucose. An enzymatic
pre- treatment that combines xylanase and cellulase was used to hydrolyze residues and release
free glucose . The obtained results demonstrate that the combination of 1 % OUAT with
hydrolyzed RH or VP resulted in a substantial (53 %) reduction in surface tension. At the end of
the fermentation, 1.65 g/L and 0.26 g/L of biosurfactant were recovered for the experiments with
hydrolyzed PV and RH, respectively. Additionally, the critical micelle dilution results demonstrate
that the two tested media allow biosurfactant production and effective reduction of the surface
tension of distilled water , even at low concentrations . This is the first report of biosurfactant
production using a mixture of these three agro-industrial residues , which can be very useful for
the sustainable production of these promising molecules.
<b>Tipo</b>: conferencePoster2024-02-19T11:54:02ZLipid production from non-detoxified lignocellulosic biomass hydrolysate by Ashbya gossypii precision fermentationFrancisco, Miguel Duarte DiasAguiar, Tatiana QuintaDomingues, LucíliaAbreu, Gabriel FerreiraMarques, SusanaGírio, Franciscohttps://hdl.handle.net/1822/882662024-01-24T08:30:27Z2024-01-24T08:30:25ZTítulo: Lipid production from non-detoxified lignocellulosic biomass hydrolysate by Ashbya gossypii precision fermentation
Autor: Francisco, Miguel Duarte Dias; Aguiar, Tatiana Quinta; Domingues, Lucília; Abreu, Gabriel Ferreira; Marques, Susana; Gírio, Francisco
Resumo: Single-cell oil production from renewable and abundant feedstocks offers a sustainable and ecofriendly
alternative to fossil-fuels consumption, an issue that has gained more attention throughout
the years and needs to be addressed in the following ones. Xylose-utilizing oleaginous A. gossypii
strains have the ability to accumulate lipids using detoxified industrial wastes as feedstock. Their
performance using non-detoxified Eucalyptus bark hydrolysate (EBH) as a substrate was evaluated
in this work. A. gossypii strains were cultivated in synthetic medium mimicking the composition of
non-detoxified EBH (SM) supplemented with 10 g/L yeast extract (YE). All strains exhibited similar
growth in SM-10YE up to 48 hours but later exhibited autolysis, which influenced their growth
dynamics. Despite this, more than 90% of glucose in the culture was consumed within 120 hours.
Notably, strain A877 reached superior lipid accumulation, especially as oleic acid. Lipid production
optimization was then performed by testing different nitrogen and micronutrient sources and
quantities. At this stage, oxygen availability was also investigated as a potential cause for autolysis
onset, and it became clear that a balance between biomass production, lipid accumulation and
autolysis was needed to achieve maximum lipid yield. Corn steep liquor (CSL), a low-cost
sustainable supplementation for EBH, showcased the best balance between all factors. In
bioreactor fermentations using non-detoxified EBH and CSL, a lipid titer of 1.42 g/L was achieved
at 78 hours, suggesting potential for high lipid production using low-cost and renewable substrates
[1].
<b>Tipo</b>: conferenceAbstract2024-01-24T08:30:25ZEvaluation of ochratoxin a (OTA) interaction with recombinant domain II of bovine serum albumin toward the development of new OTA extraction platformsAguiar, Tatiana QuintaLeal, TâniaRodrigues, Diana Isabel GomesAbrunhosa, LuísOliveira, CarlaDomingues, Lucíliahttps://hdl.handle.net/1822/882652024-01-24T08:22:47Z2024-01-24T08:22:45ZTítulo: Evaluation of ochratoxin a (OTA) interaction with recombinant domain II of bovine serum albumin toward the development of new OTA extraction platforms
Autor: Aguiar, Tatiana Quinta; Leal, Tânia; Rodrigues, Diana Isabel Gomes; Abrunhosa, Luís; Oliveira, Carla; Domingues, Lucília
Resumo: Ochratoxin A (OTA) is a mycotoxin that raises food and feed safety concerns, existing legal limits
worldwide for its presence in foodstuffs and beverages. Immuno-affinity columns (IACs) are
typically used to capture, clean-up and pre-concentrate OTA from food samples before
quantification by high- performance liquid chromatography, but their price limits their application.
Serum albumins form stable complexes with OTA, emerging as cheaper alternatives to the
antibodies used in IACs. They are composed of three globular domains, being the principal OTA
binding site located within the domain II. Containing only 6 of the 17 disulfide bonds present in
albumins, this domain should be more efficiently produce by bacteria than entire albumins.
This work envisioned the recombinant production of the bovine serum albumin (BSA) domain II in
Escherichia coli, the study of is interaction with OTA and its evaluation as ligand receptor for
developing new OTA extraction platforms. For that, this domain was cloned in fusion with His6 tag
(BDII) or with thioredoxin A (Trx)-His6 tag-TEV cleavage site (TrxBDII), and produced using BL21
and Origami 2 DE3 strains. The improved cytoplasmic oxidizing environment of Origami 2 allowed
the best production yield (18-24 mg purified protein/L culture) and fusion with Trx slighlty improved
the stability of BDII. Fluorescence quenching studies indicated weaker interaction of OTA with
TrxBDII than with the entire BSA, but no significant differences between TrxBDII and BDII. Circular
dichroism spectroscopy confirmed that OTA induced conformational changes in TrxBDII, leading
to a slight loss in the -helical content. Immobilized TrxBDII was finally used to capture OTA from
buffered solutions, allowing full retention of the mycotoxin followed by recovery upon elution.
<b>Tipo</b>: conferenceAbstract2024-01-24T08:22:45ZToward cost-effective production of recombinant human serum albumin for use in mycotoxin capture devicesRodrigues, Diana Isabel GomesAdalsteinsson, Heidar MárPinto, LavíniaAguiar, Tatiana QuintaOliveira, CarlaAbrunhosa, LuísDomingues, Lucíliahttps://hdl.handle.net/1822/882642024-01-24T08:17:43Z2024-01-24T08:17:41ZTítulo: Toward cost-effective production of recombinant human serum albumin for use in mycotoxin capture devices
Autor: Rodrigues, Diana Isabel Gomes; Adalsteinsson, Heidar Már; Pinto, Lavínia; Aguiar, Tatiana Quinta; Oliveira, Carla; Abrunhosa, Luís; Domingues, Lucília
Resumo: Human serum albumin (HSA) is a monomeric multidomain macromolecule with wide clinical and
biotechnological applications. Thus, there is a high demand for HSA, which is increasing due to
new emerging applications. Among these, the extraordinary ligand binding capacity of HSA has
been recently explored to capture mycotoxins from food and feed matrices. However, HSA is
currently produced commercially primarily from human plasma, which conveys supply limitations.
Recombinant production may be a solution to overcome this obstacle. Among the expression
systems explored for HSA production, the yeast Pichia pastoris has drawn attention for its simplicity
of genetic manipulation and high-cell density in low-priced medium, along with efficient secretory
capacity and ability to form disulfide bonds, which are major advantages over bacterial systems.
Envisioning cost-effective production of recombinant HSA for its widespread use in mycotoxin
capture devices, P. pastoris KM71H was transformed with the pPICZ9ssHSAH6 vector to produce
recombinant HSA in fusion with the His6 tag at the C-terminal (rHSA). After selecting the bestperforming
clones, minimal and complex media were tested for rHSA production in shake-flask.
The best production of stable extracellular rHSA was achieved in complex medium within 96 h of
methanol induction at nearly 0.5 g/L culture. Following rHSA purification by immobilized metal ion
affinity chromatography, fluorescence quenching studies were used to assess the suitability of the
produced rHSA for the capture of different mycotoxins. The binding constants (Ksv, L/mol) obtained
for rHSA and commercial HSA were: 8.29x105 and 6.22x105 for ochratoxin A, 6.02x104 and
2.97x104 for zearalenone, and 1.26x104 and 9.50x103 for patulin, respectively. rHSA thus displayed
results that matched those of native HSA, forming strong complexes with these mycotoxins.
<b>Tipo</b>: conferenceAbstract2024-01-24T08:17:41ZEngineered Ashbya gossypii for single-cell oil production from non-detoxified Eucalyptus bark hydrolysateFrancisco, MiguelAguiar, Tatiana QuintaMarques, S.Gírio, F.Domingues, Lucíliahttps://hdl.handle.net/1822/865292023-09-21T16:24:58Z2023-09-21T16:21:49ZTítulo: Engineered Ashbya gossypii for single-cell oil production from non-detoxified Eucalyptus bark hydrolysate
Autor: Francisco, Miguel; Aguiar, Tatiana Quinta; Marques, S.; Gírio, F.; Domingues, Lucília
Resumo: [Excerpt] Ashbya gossypii is a filamentous fungus industrially used for riboflavin production, a bioprocess in which downstream product recovery is facilitated by the ability of this fungus to undergo autolysis during the late stationary phase of growth or at low temperature [1]. In addition to
riboflavin, engineered A. gossypii strains are capable of producing other compounds of interest for the food and feed industry, among which Single-Cell Oils (SCOs) from media containing mixed formulations of detoxified corn-cob hydrolysate, sugarcane molasses or crude glycerol
[2]. [...]
<b>Tipo</b>: conferencePoster2023-09-21T16:21:49Z