Yarrowia lipolytica Extracellular Lipase Lip2 as Biocatalyst for the Ring-Opening Polymerization of ε-Caprolactone

Lipase from Yarrowia lipolytica: Production, characterization and application as an industrial biocatalyst

Yarrowia lipolytica lipase (YLL) was used as catalyst in the enzymatic ring-opening polymerization (ROP) of ε-caprolactone. This low-cost solid-state lipase produces low-molecular-weight polyesters with unique multiphase morphology as determined by carbon-13 NMR. YLL attaches sugar head groups to polycaprolactone in a one-pot biocatalytic pathway. Synthesis of α-ω-telechelic (polymer with two reactive hydroxyl end groups) PCL diols is achieved by enzymatic ROP with YLL immobilized on the macroporous resin Lewatit VPOC 1026, and in the presence of diethylene glycol or poly(ethylene glycol). Biodegradable linear polyester urethanes are prepared by polycondensation between synthesized PCL diols and hexamethylene-diisocyanate.

Surface properties and biofilm formation on resins for subtractively and additively manufactured fixed dental prostheses aged in artificial saliva: Effect of material type and surface finishing

Biodegradable polymers have emerged as fascinating materials due to their non-toxicity, environmentally benign nature and good mechanical strength. The toxic effects of non-biodegradable plastics paved way for the development of sustainable and biodegradable polymers. The engineering of biodegradable polymers employing various strategies like radical ring opening polymerization, enzymatic ring opening polymerization, anionic ring opening polymerization, photo-initiated radical polymerization, chemoenzymatic method, enzymatic polymerization, ring opening polymerization and coordinative ring opening polymerization have been discussed in this review. The application of biodegradable polymeric nanoparticles in the biomedical field and cosmetic industry is considered to be an emerging field of interest. However, this review mainly highlights the applications of selected biodegradable polymers like polylactic acid, poly(ε-caprolactone), polyethylene glycol, polyhydroxyalkanoates, poly(lactide-co-glycolide) and polytrimethyl carbonate in various fields like agriculture, biomedical, biosensing, food packaging, automobiles, wastewater treatment, textile and hygiene, cosmetics and electronic devices.

Improved performance of Yarrowia lipolytica lipase-catalyzed kinetic resolution of (R,S)-2-octanol by an integrated strategy of interfacial activation, bioimprinting and immobilization

“Water-like” ammonium-based ionic liquids for lipase activation and enzymatic polymerization

Biodegradable or bioresorbable polymers are commonly used in various pharmaceutical fields (e.g., as drug delivery systems, therapeutic systems or macromolecular drug conjugates). Polyesters are an important class of polymers widely utilized in pharmacy due to their biodegradability and biocompatibility features. In recent years, there has been increased interest in enzyme-catalyzed ring-opening polymerization (e-ROP) of cyclic esters as an alternative method of preparation of biodegradable or bioresorbable polymers. Ionic liquids (ILs) have been presented as green solvents in enzymatic ring-opening polymerization. The activity, stability, selectivity of enzymes in ILs and the ability to catalyze polyester synthesis under these conditions are discussed. Overall, the review demonstrates that e-ROP of lactones or lactides could be an effective method for the synthesis of useful biomedical polymers.

Lipase/esterase-catalyzed ring-opening polymerization: A green polyester synthesis technique

Here, the synthesis of polyglobalide (PGl) by enzymatic ring-opening polymerization (e-ROP) is investigated, using pressurized carbon dioxide (CO2), pressurized CO2+ dichloromethane (DCM), and pressurized propane as solvents. Particularly, the effects of phase equilibrium on the course of e-ROP and PGl final properties are discussed. The partition coefficients of CO2, DCM, propane, globalide and PGl were calculated with help of thermodynamic models, providing proper understanding of monomer partitioning in the reaction system. Reactions performed in pure CO2 resulted in monomer conversions of 100%. Besides, when only one liquid phase was present inside the reactor, PGl samples presented low polydispersities and high average molecular weights. When carried out in CO2+ DCM, e-ROP resulted in lower monomer conversions and PGl samples with higher polydispersities and lower average molecular weights. Finally, reactions carried out in pressurized propane (200 bar) produced PGl samples with the highest average molecular weights among the analyzed products.

Poly(ε-caprolactone) (PCL) macromonomers comprising acrylate end-functionality were synthesized via enzymatic ring-opening polymerization (eROP) by utilizing commercially availableCandida antarcticaLipase B (CALB), Novozyme-435. 2-Hydroxyethyl methacrylate (HEMA) was purposed to be the nucleophilic initiator in eROP. The side reactions generated due to the cleavage of ester bonds in HEMA and the growing polymer chains were investigated through altering polymerization period, initiator concentration, temperature, and enzyme concentration.1H NMR evaluations showed that minimum quantities of side reactions were in lower temperatures, initiator concentration, enzyme concentration, and lower monomer conversions. Gel permeation chromatography (GPC) results revealed that lower polydispersity along with number-average molecular weight of end-functionalized PCL macromonomers was obtained depending on higher initiator/monomer ratios, lower temperature (60°C), enzyme concentration (100 mg), and/or polymerization time (2 h). Furthermore, 0.1 HEMA/ε-caprolactone (CL) ratio had higher molecular weight than 0.5 HEMA/CL ratio, while keeping a close value of methacrylate transfer, total methacrylate end-groups, and lower polyester transfer.

Objective: Yarrowia lipolytica is an aerobic dimorphic yeast that produces various metabolites such as enzymes, organic acids, proteins, surfactants and has industrial potential in some biotransformation and bioremediation reactions. To be a preliminary study to industrial productions, in present study it was aimed to isolate Y. lipolytica strain from yoghurt cream, perform its molecular characterization and investigate the lipolytic activity.Material and Method: A total of 10 samples were taken from the homemade yoghurt cream obtained by fermented milk from local dairy producers in Ankara. Yeast-Peptone-Glycerol (YPG) broth and Yarrowia lipolytica Distinctive (YLD) agar media were used for isolation of the species. Species-level identification was carried out by ITS-Polymerized chain reaction analysis. Lipolytic activity was determined with Rhodamine-B/Olive Oil Agar nutrient medium procedure.Result and Discussion: Yeast colonies were isolated from homemade yoghurt creams by growing in YPG broth. Yeasts were stained with Gram staining method and Gram-positive stained ones were inoculated on YLD agar. At the end of the incubation period, the brown pigmented colony growing on YLD agar was selected as Yarrowia species. According to the molecular characterization results the brown pigmented colony was identified as Yarrowia lipolytica with a total of 358 bases, 100% sequence matching ratio and 100% similarity ratio and the strain was determined as lipase positive. The development of the Y. lipolytica strain isolated in our study as a producer culture that can be used in industrial production should be supported by further studies to benefit from its various properties.

Yarrowia lipolytica lipase has been assumed to be a good candidate for the treatment of fat malabsorption in patients with pancreatic insufficiency. Nevertheless, no systematic studies on its stability under physiological conditions pertaining to the human GI (gastrointestinal) tract have been published. Stability of various Y. lipolytica lipase powder formulations at various physiological pH values as well as the effect of digestive proteases and bile salts on enzyme activity were investigated. Results were compared with those obtained from another competing fungal lipase sourced from Candida rugosa. Among the studied formulations, Y. lipolytica lipase stabilized with gum arabic and skimmed milk powder was the most promising powder formulation. Under acidic conditions (pH 3-5), this formulation showed higher stability than those observed with the other Y. lipolytica lipase formulations and C. rugosa lipase. In addition, in the presence of gum arabic and skimmed milk powder as additives, Y. lipolytica lipase exhibited markedly higher resistance to pepsin, trypsin and chymotrypsin actions. Resistance to proteolytic degradation by digestive proteases was also by far higher than that observed with C. rugosa lipase. Similar behaviour was, however, observed when these two fungal lipases were incubated with increased concentrations of bile salts. Residual lipase activity of both fungal lipases showed a slight decrease in NaTDC (sodium taurodeoxycholate) concentration above 4 mM. Consequently, Y. lipolytica lipase formulated with gum arabic and milk powder seemed to have great potential for use as a therapeutic tool for patients with pancreatic insufficiency.

In this research, it was found that in Yarrowia lipolytica Lipase 2 (YLLIP2)-catalyzed biodiesel production, the content of fatty acid methyl esters (FAMEs) was increased by about 10% with the addition of d(+)-glucose. The result indicated that the d(+)-glucose could be used as an effective additive in YLLIP2-catalyzed biodiesel production. In accordance with the results above, the single factor experiments of key parameters in the process were first carried out. On the basis of the single factor experiment results, a five-factor, three-level response surface method was adopted to obtain the optimal reaction conditions: lipase dosage 40 IU/g oil, d(+)-glucose to lipase 1:1.05 (w/w), water content 1.95%, and reaction temperature 39.4 °C. A stoichiometric amount of methanol (11.5%, methanol/waste oil) was added in 6 times (every 4 h for each addition). A subsequent pilot scale production in a 5-ton reactor was carried out to check the performance of this method, and a good biodiesel content of 91.4% was obt...

Yarrowia lipolytica Lipase 2 Is Stable and Highly Active in Test Meals and Increases Fat Absorption in an Animal Model of Pancreatic Exocrine Insufficiency

To evaluate the effects of ionic liquids (ILs) on the microstructural features of aliphatic polyesters for biomedical applications, a series of copolymers were synthesized by lipase ring opening polymerization of rac-lactide (rac-LA) and ε-caprolactone (CL). The chemical structures of resulting polymers were characterized by 1H- and 13C-NMR and the average molecular weight (Mn) and dispersity index were characterized by gel permeation chromatography. The structure of the copolymers confirms the presence of linear polymer chains with end-functional hydroxyl groups allowing covalent coupling of the therapeutic agents. Chain microstructure of copolymers indicates the presence of both random and block copolymers depending on the synthesis conditions. Moreover, it was found that CL is the most active co-monomer during copolymerization which enhances the polymerizability of rac-LA and allows to obtain higher Mn of the copolymers. The results demonstrate that ILs could be promising solvents in synthesis of aliphatic esters for biomedical applications.