Search results for "Yarrowia"

Biosorption of nickel (II) and zinc (II) from aqueous solutions by the biomass of yeast Yarrowia lipolytica

2017

Abstract This study examined the biosorption process of Ni(II) and Zn(II) from an aqueous solution by dead biomass of Yarrowia lipolytica. Optimum biosorption conditions were determined as a function of pH, biomass dosage, contact time, and temperature. The biosorbent was characterized by FTIR, which indicated the participation of hydroxyl, carboxyl, amide and amine groups in the process of binding the metal ions. The results showed that the biosorption processes of both metal ions closely followed pseudo-second order kinetics. The equilibrium data of Ni(II) and Zn(II) ions at 20, 30 and 40°C fitted the Langmuir and Freundlich isotherm models. Langmuir isotherm provided a better fit to the …

Aroma production by solid state fermentation

2018

The adaptation of the production of γ-decalactones from submerged fermentation (SmF) to solid state fermentation (SSF) by Yarrowia lipolytica was investigated in this work. First of all, different solid matrices (corncob, cellulose sponge, luffa sponge, and castor seeds) were used for the first adaptation of the production of γ-décalactones. Luffa sponge appeared to be the most interesting solid support on which lactones were produced in higher concentrations than in the other solid matrices used. Then, the production of lactones using luffa sponge as the solid support was carried out in three types of SSF reactors to monitor different aeration conditions (without aeration, with a static ae…

Toxicity of fatty acid hydroperoxides towards Yarrowia lipolytica: Implication of their membrane fluidizing action

2007

Abstract Linoleic acid hydroperoxide (HPOD), substrate of hydroperoxide lyase, an enzyme of the lipoxygenase pathway, can be transformed into many aromatic compounds, the so-called “green notes”. The presence of linoleic acid hydroperoxide in the culture medium of Yarrowia lipolytica, the yeast expressing the cloned hydroperoxide lyase of green bell pepper, undoubtedly exerted an inhibition on the growth and a toxic effect with 90% of yeast cells died after 120 min of exposition in 100 mM HPOD solution. The increase in cell membrane fluidity evaluated by measuring fluorescence generalized polarization with the increasing concentration of HPOD in the medium confirmed the fluidizing action of…

Increased electron donor and electron acceptor characters enhance the adhesion between oil droplets and cells of Yarrowia lipolytica as evaluated by …

2003

The adhesion of methyl ricinoleate droplets to cells of the yeast Yarrowia lipolytica was investigated. A new cytometric method, relying on the double staining of fatty globules with Nile Red and of cells with Calcofluor, enabled us to quantify methyl ricinoleate droplet adhesion to cells precultured on a hydrophilic or on a hydrophobic carbon source. In this last case, droplet adsorption was enhanced and a MATS (microbial adhesion to solvents) test revealed that this increase was due to Lewis acid-base interactions and not to an increase in the hydrophobic properties of the cell surface. These preliminary results demonstrate that the developed cytometric method is promising for various app…

Physiologic and biologic mechanisms induced in Yarrowia lipolytica in response to physico-chemical modifications of cells environment

2010

Hydrophobe compounds are known as carbon source which could be used by yeast like Yarrowia lipolytica for multi purposes. These compounds may cause disturbance in yeast but also reported as confer some resistance to cells towards environmental stress. Here, we study the role of methyl oleate as carbon source on resistance of Y. lipolytica in response to stress of an amphiphilic compound, -dodecalactone, and to heat shock. Results show that cells grown in oleate are more resistant to these stresses than cells grown in glucose. This work reveals the role of the lipids bodies in cells response to stress and that cells manifest in different ways in response to these stresses. An accumulation o…

Biosorpcja niklu (II) i cynku (II) z roztworów wodnych przez biomasę drożdży Yarrowia lipolytica

2016

Stymulacja rozkładu substancji ropopochodnych w skażonej glebie z wykorzystaniem nadtlenku wodoru i szczepionki Yarrowia lipolytica A101

2016

Skażenia substancjami ropopochodnymi stanowią ogromny problem, nie tylko w rolnictwie, ponieważ negatywnie wpływają na właściwości fizyko-chemiczne i aktywność biologiczną gleb. Związki te mogą się również akumulować w roślinach lub wraz z pyłem osiadać na ich zielonych częściach. Większość z nich to substancje karcenogenne, dlatego ich usuwanie ze środowiska wymaga zastosowania efektywnych, tanich i bezpiecznych metod. W warunkach laboratoryjnych oceniono przydatność łącznego wykorzystania techniki stymulacji nadtlenkiem wodoru i bioaugmentacji szczepionką drożdżową Yarrowia lipolytica A101 do oczyszczania gleby z substancji ropopochodnych oraz wpływ na dynamikę zmian mikrobioty gleby. Wyk…

Increased electron donor and electron acceptor characters enhance the adhesion between oil droplets and cells of Yarrowia lipolytica as evaluated by …

2003

International audience; The adhesion of methyl ricinoleate droplets to cells of the yeast Yarrowia lipolytica was investigated. A new cytometric method, relying on the double staining of fatty globules with Nile Red and of cells with Calcofluor, enabled us to quantify methyl ricinoleate droplet adhesion to cells precultured on a hydrophilic or on a hydrophobic carbon source. In this last case, droplet adsorption was enhanced and a MATS (microbial adhesion to solvents) test revealed that this increase was due to Lewis acid-base interactions and not to an increase in the hydrophobic properties of the cell surface. These preliminary results demonstrate that the developed cytometric method is p…

Etude des mécanismes physiologiques et moléculaires permettant la prise en charge des substrats hydrophobes par la levure Yarrowia lipolytica au nive…

2012

Yarrowia lipolytica can grow on many hydrophobic substrates and metabolize them via the β-oxidation pathway or store them into lipid bodies. The first contact between the cell and the hydrophobic substrates is by the cell wall. In this step, cell-wall proteins (CWP), β-glucane and chitin of the cell wall could play an important role for the adhesion and uptake of hydrophobic substrates. The aim of this work was to study the effect of a hydrophobic carbon source (compared with glucose) and the culture medium composition on the cell wall composition and the melanin production by Y. lipolytica. The results of our biochemical and molecular analysis showed that the presence of methyl oleate and …

A singleFKShomologue inYarrowia lipolyticais essential for viability

2002

The synthesis of β-1,3-glucan, the structural component of the yeast cell wall which gives shape to the cell, occurs at the plasma membrane and is the result of the activity of at least a two-component complex. Fks1p is the catalytic subunit directly responsible for the synthesis of β-1,3-glucan, whilst the second subunit, Rho1p, has a GTP-dependent regulatory role. FKS1 has been characterized in Saccharomyces cerevisiae, where its function is at least partially redundant with that of FKS2/GSC2. FKS homologues have also been identified in several other fungal species, including Candida albicans, Schizosaccharomyces pombe, Aspergillus nidulans, Cryptococcus neoformans and Paracoccidiodes bra…