Articles de revues : « Bio-Based fatty acids »

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Stavila, Erythrina, Frita Yuliati, Azis Adharis, Joddy Arya Laksmono et Muhammad Iqbal. « Recent advances in synthesis of polymers based on palm oil and its fatty acids ». RSC Advances 13, n^o 22 (2023) : 14747–75. http://dx.doi.org/10.1039/d3ra01913f.

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Frihart, Charles R. « Chemistry of Dimer Acid Production from Fatty Acids and the Structure–Property Relationships of Polyamides Made from These Dimer Acids ». Polymers 15, n^o 16 (9 août 2023) : 3345. http://dx.doi.org/10.3390/polym15163345.

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While there is abundant literature on using a wide range of biomaterials to make polymers for various adhesive applications, most researchers have generally overlooked developing new adhesives from commercially available bio-based dimerized fatty acids. Some of the literature on the chemistry taking place during the clay-catalyzed dimerization of unsaturated fatty acids is generally misleading in that the mechanisms are not consistent with the structures of these dimers and a by-product isostearic acid. A selective acid-catalyzed interlayer model is much more logical than the widely accepted model of clay-catalyzed Diels–Alder reactions. The resulting dimers have a variety of linkages limiting large crystal formation either as oligomeric amides or polyamides. These highly aliphatic fatty acid dimers are used to make a wide range of hot melt polyamide adhesives. The specific structures and amounts of the diacids and diamines and their relative ratios have a big effect on the bio-based polyamide mechanical properties, but analysis of the structure–property relationships has seldom been attempted, since the data are mainly in the patent literature. The diacids derived from plant oils are valuable for making polyamides because of their very high bio-based content and highly tunable properties.

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Mensah, Joel B., Adrian H. Hergesell, Sebastian Brosch, Christiane Golchert, Jens Artz et Regina Palkovits. « Catalytic deoxygenation of bio-based 3-hydroxydecanoic acid to secondary alcohols and alkanes ». Green Chemistry 22, n^o 11 (2020) : 3522–31. http://dx.doi.org/10.1039/d0gc00691b.

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McDowall, Stewart Charles, Maria Braune et Roy Nitzsche. « Recovery of bio-based medium-chain fatty acids with membrane filtration ». Separation and Purification Technology 286 (avril 2022) : 120430. http://dx.doi.org/10.1016/j.seppur.2021.120430.

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Beller, Harry R., Taek Soon Lee et Leonard Katz. « Natural products as biofuels and bio-based chemicals : fatty acids and isoprenoids ». Natural Product Reports 32, n^o 10 (2015) : 1508–26. http://dx.doi.org/10.1039/c5np00068h.

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Narra, Naganna, Badari Narayana Prasad Rachapudi, Sahithya Phani Babu Vemulapalli et Padmaja V. Korlipara. « Lewis-acid catalyzed synthesis and characterization of novel castor fatty acid-based cyclic carbonates ». RSC Advances 6, n^o 31 (2016) : 25703–12. http://dx.doi.org/10.1039/c6ra00880a.

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Simar-Mentières, S., F. Nesslany, M. L. Sola, S. Mortier, J. M. Raimbault, F. Gondelle, L. Chabot, P. Pandard, D. Wils et A. Chentouf. « Toxicology and Biodegradability of a Phthalate-Free and Bio-Based Novel Plasticizer ». Journal of Toxicology 2021 (12 juillet 2021) : 1–15. http://dx.doi.org/10.1155/2021/9970896.

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Phthalate esters, mainly di-ethylhexylphthalate (DEHP), represent a class of chemicals primarily used as plasticizers for polyvinyl chloride in a wide range of domestic and industrial applications. These phthalate esters are low-toxicity environmental contaminants. To address these drawbacks, POLYSORB® ID 37, a blend of diesters obtained from esterification of isosorbide with plant-based fatty acids, was developed. The company can now offer PVC manufacturers a new product which competes with phthalates and other such chemicals. The market for plasticizers is very important, and ROQUETTE intends to provide a more sustainable and safer product. Isosorbide diester is bio-based (made from glucose and vegetable fatty acids). This plasticizer is registered in REACH regulation for high volumes (>1000 T/year). Risk assessment was obtained by conducting a wide range of biodegradability and toxicological protocols, using rodent models, according to established guidelines. Overall, all of the toxicological and biodegradability studies demonstrated that POLYSORB® ID 37 is nontoxic to mammalian life and is readily biodegradable.

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Lamarzelle, Océane, Geoffrey Hibert, Sébastien Lecommandoux, Etienne Grau et Henri Cramail. « A thioglycerol route to bio-based bis-cyclic carbonates : poly(hydroxyurethane) preparation and post-functionalization ». Polymer Chemistry 8, n^o 22 (2017) : 3438–47. http://dx.doi.org/10.1039/c7py00556c.

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He, Songbo, Thomas Sjouke Kramer, Dian Sukmayanda Santosa, Andre Heeres et Hero Jan Heeres. « Catalytic conversion of glycerol and co-feeds (fatty acids, alcohols, and alkanes) to bio-based aromatics : remarkable and unprecedented synergetic effects on catalyst performance ». Green Chemistry 24, n^o 2 (2022) : 941–49. http://dx.doi.org/10.1039/d1gc03531b.

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Synergetic effects between glycerol and various co-feeds (including alkanes, alcohols, and free fatty acids) lead to higher catalytic activity, prolonged catalyst life-time, and improved catalyst regenerability for bio-based aromatics formation.

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Kulomaa, Tuomas, Jorma Matikainen, Pirkko Karhunen, Mikko Heikkilä, Juha Fiskari et Ilkka Kilpeläinen. « Cellulose fatty acid esters as sustainable film materials – effect of side chain structure on barrier and mechanical properties ». RSC Advances 5, n^o 98 (2015) : 80702–8. http://dx.doi.org/10.1039/c5ra12671a.

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Bio-based films were prepared by acylation of cellulose with saturated, unsaturated and branched fatty acids. The products showed increased thermal stability, low water vapour transmission rates and enhanced tensile and elastic properties.

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Fridrihsone, Anda, Arnis Abolins et Mikelis Kirpluks. « Screening Life Cycle Assessment of Tall Oil-Based Polyols Suitable for Rigid Polyurethane Foams ». Energies 13, n^o 20 (9 octobre 2020) : 5249. http://dx.doi.org/10.3390/en13205249.

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A screening Life Cycle Assessment (LCA) of tall oil-based bio-polyols suitable for rigid polyurethane (PU) foams has been carried out. The goal was to identify the hot-spots and data gaps. The system under investigation is three different tall oil fatty acids (TOFA)-based bio-polyol synthesis with a cradle-to-gate approach, from the production of raw materials to the synthesis of TOFA based bio-polyols at a pilot-scale reactor. The synthesis steps that give the most significant environmental footprint hot-spots were identified. The results showed the bio-based feedstock was the main environmental hot-spot in the bio-polyol production process. Future research directions have been highlighted.

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Yang, Zhe, Yan Bin Zhu, Fang Peng et Chang Qing Fu. « Preparation and Application of Undecylenate Based Diol for Bio-Based Waterborne Polyurethane Dispersion ». Advanced Materials Research 955-959 (juin 2014) : 88–91. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.88.

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The undecylenate based diol (UAD) has been synthesized from undecylenate by esterification and thiol-ene click reaction sequently, and then it was used as a diol to prepare bio-based waterborne polyurethane (WPU) reacting with isophorone diisocyanate (IPDI) and castor oil-based carboxyl hydrophilic chain extender. The structure of undecylenate based diol was verified by hydrogen proton nuclear magnetic resonance (1H NMR). Fourier transform infrared spectroscopy (FT-IR) was used to characterize the structure of WPU film. Furthermore, particle size and viscosity were used to character apparent properties of the bio-based waterborne polyurethane dispersion. The result shows that: bio-based waterborne polyurethane dispersion is transparent and very stable under room temperature. This work provides a simple and efficient method for the preparation of fatty acids based polyols and bio-based waterborne polyurethanes.

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Benítez, José J., Paula M. Castillo, José C. del Río, Manuel León-Camacho, Eva Domínguez, Antonio Heredia, Susana Guzmán-Puyol, Athanassia Athanassiou et José A. Heredia-Guerrero. « Valorization of Tomato Processing by-Products : Fatty Acid Extraction and Production of Bio-Based Materials ». Materials 11, n^o 11 (7 novembre 2018) : 2211. http://dx.doi.org/10.3390/ma11112211.

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A method consisting of the alkaline hydrolysis of tomato pomace by-products has been optimized to obtain a mixture of unsaturated and polyhydroxylated fatty acids as well as a non-hydrolysable secondary residue. Reaction rates and the activation energy of the hydrolysis were calculated to reduce costs associated with chemicals and energy consumption. Lipid and non-hydrolysable fractions were chemically (infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC-MS)) and thermally (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)) characterized. In addition, the fatty acid mixture was used to produce cutin-based polyesters. Freestanding films were prepared by non-catalyzed melt-polycondensation and characterized by Attenuated Total Reflected-Fourier Transform Infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (NMR), DSC, TGA, Water Contact Angles (WCA), and tensile tests. These bio-based polymers were hydrophobic, insoluble, infusible, and thermally stable, their physical properties being tunable by controlling the presence of unsaturated fatty acids and oxygen in the reaction. The participation of an oxidative crosslinking side reaction is proposed to be responsible for such modifications.

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Ivdre, Aiga, Mikelis Kirpluks, Arnis Abolins, Laima Vevere, Beatrise Sture, Aigars Paze, Daniela Godina, Janis Rizikovs et Ugis Cabulis. « Rigid Polyurethane Foams’ Development and Optimization from Polyols Based on Depolymerized Suberin and Tall Oil Fatty Acids ». Polymers 16, n^o 7 (29 mars 2024) : 942. http://dx.doi.org/10.3390/polym16070942.

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The utilization of polyols derived from renewable sources presents an opportunity to enhance the sustainability of rigid polyurethane (PUR) foams, thereby contributing to the advancement of a circular bioeconomy. This study explores the development of PUR rigid foams exclusively using polyols sourced from second-generation renewable biomass feedstocks, specifically depolymerized birch bark suberin (suberinic acids) and tall oil fatty acids. The polyols achieved a total renewable material content as high as 74%, with a suberinic acid content of 37%. Response surface modeling was employed to determine the optimal bio-polyol, blowing agents, and catalyst content, hence, optimizing the bio-based foam formulations. In addition, response surface modeling was applied to rigid PUR foam formulations based on commercially available petroleum-based polyols for comparison. The results, including apparent density (~40–44 kg/m3), closed cell content (~95%), compression strength (>0.2 MPa, parallel to the foaming direction), and thermal conductivity (~0.019 W/(m·K)), demonstrated that the suberinic acids-based rigid PUR foam exhibited competitive qualities in comparison to petroleum-based polyols. Remarkably, the bio-based rigid PUR foams comprised up to 29% renewable materials. These findings highlight the potential of suberinic acid-tall oil polyols as effective candidates for developing rigid PUR foams, offering promising solutions for sustainable insulation applications.

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Rajappan, Sinu C., Brad J. Davis, Isaiah T. Dishner, Travis L. Thornell, John J. Peyrefitte et Yoan C. Simon. « Reversible hetero-Diels–Alder amine hardener as drop-in replacement for healable epoxy coatings ». Polymer Chemistry 13, n^o 6 (2022) : 741–47. http://dx.doi.org/10.1039/d1py00917f.

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Replacing commercial hardeners with bio-sourced fatty acids linked by hetero Diels–Alder (HDA) motifs enabled epoxy-amine coatings with intrinsic self-healing properties. The HDA-based coatings demonstrate scratch healing at 95 °C within 15 min.

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Kocetkovs, Vjaceslavs, Vitalijs Radenkovs, Karina Juhnevica-Radenkova et Sandra Muizniece-Brasava. « Variation in the Fatty Acid and Amino Acid Profiles of Pasteurized Liquid Whole Hen Egg Products Stored in Four Types of Packaging ». Animals 12, n^o 21 (30 octobre 2022) : 2990. http://dx.doi.org/10.3390/ani12212990.

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This study aimed to determine the ability of high-density polyethylene, polyethylene terephthalate, Tetra Rex® Bio-based packaging, and Doypack (stand-up pouches) packaging to maintain the nutritional quality and safety of liquid whole egg products for 35 days of refrigerated storage. High-grade hen eggs were used for the preparation of liquid whole egg products (LWEPs). The conformity of eggs quality to grade A was supported by the initial screening of the raw materials’ physical–chemical attributes, which remained unchanged during the 25 days of storage. The obtained results indicated that the content of fatty acids in LWEPs was affected by both storage time and packaging material. However, the better preservation of monounsaturated fatty acids was achieved by polyethylene terephthalate, followed by high-density polyethylene packaging. Meanwhile, a statistically significant advantage of polyethylene terephthalate over other packaging materials was also confirmed regarding the maintenance of polyunsaturated fatty acids during 35 days of LWEPs storage. Relative fluctuations in the number of fatty acids in Tetra Rex® Bio-based and Doypack-stored LWEPs revealed their disadvantages manifested by exfoliation of composite layers, which perhaps was the main cause of extensive moisture loss. Overall, due to superior barrier properties, polyethylene terephthalate packaging demonstrated better preservation of amino acids. Only as much as a 2.1% decrease was observed between the initial value and the 35th day of LWEP storage. From a microbiological standpoint, all materials demonstrated the ability to ensure the microbiological safety of products during 35 days of storage, as the maximum allowed limit of 105 CFU g−1 was not exceeded.

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Pomilovskis, Ralfs, Inese Mierina, Anda Fridrihsone et Mikelis Kirpluks. « Bio-Based Polymer Developments from Tall Oil Fatty Acids by Exploiting Michael Addition ». Polymers 14, n^o 19 (28 septembre 2022) : 4068. http://dx.doi.org/10.3390/polym14194068.

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In this study, previously developed acetoacetates of two tall-oil-based and two commercial polyols were used to obtain polymers by the Michael reaction. The development of polymer formulations with varying cross-link density was enabled by different bio-based monomers in combination with different acrylates—bisphenol A ethoxylate diacrylate, trimethylolpropane triacrylate, and pentaerythritol tetraacrylate. New polymer materials are based on the same polyols that are suitable for polyurethanes. The new polymers have qualities comparable to polyurethanes and are obtained without the drawbacks that come with polyurethane extractions, such as the use of hazardous isocyanates or reactions under harsh conditions in the case of non-isocyanate polyurethanes. Dynamic mechanical analysis, differential scanning calorimetry, thermal gravimetric analysis, and universal strength testing equipment were used to investigate the physical and thermal characteristics of the created polymers. Polymers with a wide range of thermal and mechanical properties were obtained (glass transition temperature from 21 to 63 °C; tensile modulus (Young’s) from 8 MPa to 2710 MPa and tensile strength from 4 to 52 MPa). The synthesized polymers are thermally stable up to 300 °C. The suggested method may be used to make two-component polymer foams, coatings, resins, and composite matrices.

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Sung, Jonggeun, et Xiuzhi Susan Sun. « Cardanol modified fatty acids from camelina oils for flexible bio-based acrylates coatings ». Progress in Organic Coatings 123 (octobre 2018) : 242–53. http://dx.doi.org/10.1016/j.porgcoat.2018.02.008.

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Usman, Faruk, Aminu Muhammad Bayawa, Abdullahi Muhammad Sokoto et Abdullahi Bako Rabah. « Nickel-Based Catalysts for Deoxygenation of Biorefinery Products to Renewable Fuels : A Mini Review ». Dutse Journal of Pure and Applied Sciences 10, n^o 2b (17 juillet 2024) : 210–21. http://dx.doi.org/10.4314/dujopas.v10i2b.22.

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Nickel-based catalysts have shown decent performance in deoxygenation reactions. Although palladium catalyst is very effective for this reaction, its high cost increases the cost of production. This review concerns the deoxygenation reactions of higher fatty acids, vegetable oils, bio-oil and its model compounds to fuels using nickel-based catalysts. The hydrodeoxygenation and decarboxylation of model fatty acids and vegetable oils over nickel-based catalysts have been found to produce appreciable hydrocarbons that can be used directly as fuel in diesel engines. Similarly, bio-oil and its model compounds produce hydrocarbons in the presence of various nickel-based catalysts, but the yield is not as prominent as in vegetable oils. In general, the catalytic performance of nickel in such reactions depends on the co-metal, support and the reaction conditions. Like palladium and platinum, the electronic properties of nickel-metal have been shown to significantly contribute to the cleavage of the C–C or C–H bonds during the reactions. It has been reported that hydrogen molecule is stuck in the defect sites of the nickel=metal surface resulting in a decrease in the activation energy of hydrogen dissociation. Nickel, is, therefore, one of the most promising metals for catalyzing hydrodeoxygenation of bio-oils into hydrocarbons.

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Kirpluks, Mikelis, Edgars Vanags, Arnis Abolins, Slawomir Michalowski, Anda Fridrihsone et Ugis Cabulis. « High Functionality Bio-Polyols from Tall Oil and Rigid Polyurethane Foams Formulated Solely Using Bio-Polyols ». Materials 13, n^o 8 (24 avril 2020) : 1985. http://dx.doi.org/10.3390/ma13081985.

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High-quality rigid polyurethane (PU) foam thermal insulation material has been developed solely using bio-polyols synthesized from second-generation bio-based feedstock. High functionality bio-polyols were synthesized from cellulose production side stream—tall oil fatty acids by oxirane ring-opening as well as esterification reactions with different polyfunctional alcohols, such as diethylene glycol, trimethylolpropane, triethanolamine, and diethanolamine. Four different high functionality bio-polyols were combined with bio-polyol obtained from tall oil esterification with triethanolamine to develop rigid PU foam formulations applicable as thermal insulation material. The developed formulations were optimized using response surface modeling to find optimal bio-polyol and physical blowing agent: c-pentane content. The optimized bio-based rigid PU foam formulations delivered comparable thermal insulation properties to the petro-chemical alternative.

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Abolins, Arnis, Ralfs Pomilovskis, Edgars Vanags, Inese Mierina, Slawomir Michalowski, Anda Fridrihsone et Mikelis Kirpluks. « Impact of Different Epoxidation Approaches of Tall Oil Fatty Acids on Rigid Polyurethane Foam Thermal Insulation ». Materials 14, n^o 4 (13 février 2021) : 894. http://dx.doi.org/10.3390/ma14040894.

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A second-generation bio-based feedstock—tall oil fatty acids—was epoxidised via two pathways. Oxirane rings were introduced into the fatty acid carbon backbone using a heterogeneous epoxidation catalyst-ion exchange resin Amberlite IR-120 H or enzyme catalyst Candida antarctica lipase B under the trade name Novozym® 435. High functionality bio-polyols were synthesised from the obtained epoxidated tall oil fatty acids by oxirane ring-opening and subsequent esterification reactions with different polyfunctional alcohols: trimethylolpropane and triethanolamine. The synthesised epoxidised tall oil fatty acids (ETOFA) were studied by proton nuclear magnetic resonance. The chemical structure of obtained polyols was studied by Fourier-transform infrared spectroscopy and size exclusion chromatography. Average molecular weight and polydispersity of polyols were determined from size exclusion chromatography data. The obtained polyols were used to develop rigid polyurethane (PU) foam thermal insulation material with an approximate density of 40 kg/m3. Thermal conductivity, apparent density and compression strength of the rigid PU foams were determined. The rigid PU foams obtained from polyols synthesised using Novozym® 435 catalyst had superior properties in comparison to rigid PU foams obtained from polyols synthesised using Amberlite IR-120 H. The developed rigid PU foams had an excellent thermal conductivity of 21.2–25.9 mW/(m·K).

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Masrukan, Masrukan, Sri Raharjo, Rini Yanti et Widiastuti Setyaningsih. « Dual Response Optimization of Ultrasound-Assisted Oil Extraction from Milkfish By-Products using D-Limonene as A Bio-Based Solvent ». Trends in Sciences 21 (18 juillet 2024) : Manuscript. http://dx.doi.org/10.48048/tis.2024.8016.

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Fish oil has been reported to have positive health effects because it is rich in n-3 essential fatty acids. This study aimed to determine the optimal conditions for achieving a high oil yield and omega-3 content from milkfish by-products using ultrasound-assisted extraction (UAE) combined with a d-limonene solvent. The Box-Behnken design (BBD) combined with response surface methodology was successfully used to determine the optimum extraction conditions for omega-3 fatty acids based on several factors: Temperature (30, 60 and 90 °C), solvent-to-sample ratio (2:1, 4:1 and 6:1 mL/g) and time (6, 38 and 70 min). The ANOVA results showed that sonication time (p < 0.05) and temperature (p < 0.05) had a significant influence on omega-3 fatty acids and the yield of extracted oil. The optimal extraction conditions for UAE were 68 min, 84 °C, and a solvent-to-sample ratio of 3:1 mL/g resulting in high oil recovery (21.95 %) containing omega-3 compounds (12.50 %). Additionally, the resulting oil was also further characterized by quality parameters (acid, peroxide, anisidine-total oxidation and iodine values) as well as the fatty acid composition. The developed milkfish oil met the IFOS™ (International Fish Oil Standards) criteria hence applicable for industrial oil production.

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Magalhães, Solange, María José Aliaño-González, Pedro F. Cruz, Rose Rosenberg, Dirk Haffke, Magnus Norgren, Luís Alves, Bruno Medronho et Maria da Graça Rasteiro. « Customising Sustainable Bio-Based Polyelectrolytes : Introduction of Charged and Hydrophobic Groups in Cellulose ». Polymers 16, n^o 22 (5 novembre 2024) : 3105. http://dx.doi.org/10.3390/polym16223105.

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Cellulose has been widely explored as a sustainable alternative to synthetic polymers in industrial applications, thanks to its advantageous properties. The introduction of chemical modifications on cellulose structure, focusing on cationic and hydrophobic modifications, can enhance its functionality and expand the range of applications. In the present work, cationization was carried out through a two-step process involving sodium periodate oxidation followed by a reaction with the Girard T reagent, yielding a degree of substitution for cationic groups (DScationic) between 0.3 and 1.8. Hydrophobic modification was achieved via esterification with fatty acids derived from commercial plant oils, using an enzyme-assisted, environmentally friendly method. Lipase-catalysed hydrolysis, optimised at 0.25% enzyme concentration and with a 1 h reaction time, produced an 84% yield of fatty acids, confirmed by FTIR and NMR analyses. The degree of substitution for hydrophobic groups (DShydrophobic) ranged from 0.09 to 0.66. The molecular weight (MW) of the modified cellulose derivatives varied from 1.8 to 141 kDa. This dual modification strategy enables the creation of cellulose-based polymers with controlled electrostatic and hydrophobic characteristics, customisable for specific industrial applications. Our approach presents a sustainable and flexible solution for developing cellulose derivatives tailored to diverse industrial needs.

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Sethi, Deepak, Thomas O. Butler, Faqih Shuhaili et Seetharaman Vaidyanathan. « Diatoms for Carbon Sequestration and Bio-Based Manufacturing ». Biology 9, n^o 8 (10 août 2020) : 217. http://dx.doi.org/10.3390/biology9080217.

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Carbon dioxide (CO2) is a major greenhouse gas responsible for climate change. Diatoms, a natural sink of atmospheric CO2, can be cultivated industrially in autotrophic and mixotrophic modes for the purpose of CO2 sequestration. In addition, the metabolic diversity exhibited by this group of photosynthetic organisms provides avenues to redirect the captured carbon into products of value. These include lipids, omega-3 fatty acids, pigments, antioxidants, exopolysaccharides, sulphated polysaccharides, and other valuable metabolites that can be produced in environmentally sustainable bio-manufacturing processes. To realize the potential of diatoms, expansion of our knowledge of carbon supply, CO2 uptake and fixation by these organisms, in conjunction with ways to enhance metabolic routing of the fixed carbon to products of value is required. In this review, current knowledge is explored, with an evaluation of the potential of diatoms for carbon capture and bio-based manufacturing.

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Singh, Ram Kumar, Avijit Dey, Shubham Thakur, Mala Singh et Puran Chand Lailer. « Modulation of Murrah Buffalo (Bubalus bubalis) Rumen Functions for In Vitro Fatty Acid Bio-Hydrogenation, Methane Production and Fermentation Pattern of Total Mixed Ration Supplemented with Allium sativum (Garlic) Essential Oils ». Fermentation 9, n^o 7 (29 juin 2023) : 615. http://dx.doi.org/10.3390/fermentation9070615.

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The potential for plant-origin essential oils to modulate rumen functions for reducing bio-hydrogenation of fatty acids and methane production has been a significant area of research in recent times. This study investigated the effects supplementation of garlic (Allium sativum) essential oils have on in vitro bio-hydrogenation of fatty acids, methanogenesis and fermentation characteristics of total mixed ration in buffalo with the aim of enhancing conjugated linoleic acid (CLA) content in animal products as well as reducing environmental pollution. Allium sativum (AS) essential oils were examined at four levels [0 (Control), 33.33 µL (AS-1), 83.33 µL (AS-2) and 166.66 µL (AS-3) per litre of buffered rumen fluid] in a radio-frequency based automatic gas production system (ANKOM-RF). Two bottles per treatment per run over two incubation runs were undertaken to gain representative results. Oats hay and concentrate mixture (1:1) was used as a substrate (500 ± 5 mg) and incubated with 60 mL of buffered rumen fluid in 250 mL ANKOM bottles fitted with automatic an gas recording system at 39 °C for 24 h, following standard in vitro gas production protocols. The results demonstrated a reduction (p < 0.01) in lipid bio-hydrogenation, measured by lowered saturated fatty acids and enhanced unsaturated fatty acids on the supplementation of AS essential oils, irrespective of the dose levels. Moreover, the increased (p < 0.01) production of trans vaccenic (trans C18:1) acid (TVA) following graded dose supplementations of the AS essential oils increased the production of conjugated linoleic acids (CLA) in animal products. Although, reduced methane production (p < 0.01) was evidenced, the decrease in total gas production and feed digestibility (TDDM) demonstrated the strong antimicrobial properties of AS at all dose levels. The study reveals that the Allium sativam (Garlic) essential oils have the potential to be an agent for the reduction of the rumen biohydrogenation of fatty acids and methanogenesis. However, in vivo examination is necessary to validate the findings and confirm its suitability for use as an additive to enhance nutraceutical and organoleptic properties in animal products.

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Jeliani, Zahra Zarei, Nasrin Fazelian et Morteza Yousefzadi. « Introduction of macroalgae as a source of biodiesel in Iran : analysis of total lipid content, fatty acid and biodiesel indices ». Journal of the Marine Biological Association of the United Kingdom 101, n^o 3 (mai 2021) : 527–34. http://dx.doi.org/10.1017/s0025315421000382.

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AbstractThe aim of this work was to describe and compare the main fatty acids and biodiesel indices of some green and brown macroalgae (seaweeds) collected from the Persian Gulf, as an alternative raw material for renewable biodiesel production. The macroalgae showed low lipid content (< 10% DW) but marine macroalgae with total lipid content > 5% DW are a good source for biodiesel production. The total lipid content and saturated fatty acids (SFAs) of green algae were higher than that of brown algae, while higher accumulation of unsaturated fatty acids (USFAs) was observed in brown seaweeds. Further, the main fatty acid in all studied seaweeds was palmitic acid (C16:0), which was followed by oleic acid (C18:1). The results of this work showed that three of the green algae, especially C. sertularioides, could be a potential source of fatty acids for biodiesel production owing to their high total lipid content, high cold flow indices (long chain saturated factor, cold filter plugging point and cloud point) and a fatty acid profile rich in SFAs with a high amount of C18:1, which is suitable for oil-based bio products. In contrast, the brown seaweeds Sargassum boveanum and Sirophysalis trinodis lipid content had a high proportion of polyunsaturated fatty acids (PUFAs), which makes them suitable for replacing fish oil.

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Bueno-Ferrer, Carmen, Elodie Hablot, Florence Perrin-Sarazin, M. Carmen Garrigós, Alfonso Jiménez et Luc Averous. « Structure and Morphology of New Bio-Based Thermoplastic Polyurethanes Obtained From Dimeric Fatty Acids ». Macromolecular Materials and Engineering 297, n^o 8 (7 février 2012) : 777–84. http://dx.doi.org/10.1002/mame.201100278.

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Cellat, Kemal, Beyza Beyhan, Caner Güngör, Yeliz Konuklu, Okan Karahan, Cengiz Dündar et Halime Paksoy. « Thermal enhancement of concrete by adding bio-based fatty acids as phase change materials ». Energy and Buildings 106 (novembre 2015) : 156–63. http://dx.doi.org/10.1016/j.enbuild.2015.05.035.

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Palanti, Sabrina, Ali Temiz, Gaye Köse Demirel, Gökhan Hekimoğlu, Ahmet Sarı, Meysam Nazari, Mohamed Jebrane, Thomas Schnabel et Nasko Terziev. « Bio-Based Phase Change Materials for Wooden Building Applications ». Forests 13, n^o 4 (12 avril 2022) : 603. http://dx.doi.org/10.3390/f13040603.

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Solid wood can serve multifunctionality for energy savings in buildings. The study reveals the results of biodeterioration and degradation of solid Scots pine wood used to incorporate single or multicomponent fatty acid mixtures as bio-based phase change materials (BPCMs). The sapwood samples were impregnated with capric acid (CA), methyl palmitate (MP), lauryl alcohol (LA) and a mixture of coconut oil fatty acids and linoleic acid (CoFA-LA). The samples were tested against subterranean termites by an Italian species (Reticulitermes lucifugus), the wood boring beetle Hylotrupes bajulus and mold through a discoloration test. Tested against termites, the impregnated samples were significantly less susceptible to the attack than the controls, i.e., the tested BPCMs were resistant to R. lucifugus. The only test with MP terminated at the moment against H. bajulus showed positive results with no larvae surviving. The mold discoloration test revealed that the wood impregnated with CoFA-LA was identically susceptible to mold discoloration when compared to the control, nonimpregnated samples. This pioneer study verifies that solid wood employed for the encapsulation of BPCMs for building purposes can serve identically or somewhat better than similar wooden building elements regarding attacks of the above microorganisms and insects. Such multifunctional building elements will be tested further in a pilot scale building to characterize better the durability aspects of the new materials.

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Pomilovskis, Ralfs, Inese Mierina, Hynek Beneš, Olga Trhlíková, Arnis Abolins, Anda Fridrihsone et Mikelis Kirpluks. « The Synthesis of Bio-Based Michael Donors from Tall Oil Fatty Acids for Polymer Development ». Polymers 14, n^o 19 (30 septembre 2022) : 4107. http://dx.doi.org/10.3390/polym14194107.

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In this study, the synthesis of a Michael donor compound from cellulose production by-products—tall oil fatty acids—was developed. The developed Michael donor compounds can be further used to obtain polymeric materials after nucleophilic polymerization through the Michael reaction. It can be a promising alternative method for conventional polyurethane materials, and the Michael addition polymerization reaction takes place under milder conditions than non-isocyanate polyurethane production technology, which requires high pressure, high temperature and a long reaction time. Different polyols, the precursors for Michael donor components, were synthesized from epoxidized tall oil fatty acids by an oxirane ring-opening and esterification reaction with different alcohols (trimethylolpropane and 1,4-butanediol). The addition of functional groups necessary for the Michael reaction was carried out by a transesterification reaction of polyol hydroxyl groups with tert-butyl acetoacetate ester. The following properties of the developed polyols and their acetoacetates were analyzed: hydroxyl value, acid value, moisture content and viscosity. The chemical structure was analyzed using Fourier transform infrared spectroscopy, gel permeation chromatography, size-exclusion chromatography and nuclear magnetic resonance. Matrix-assisted laser desorption/ionization analysis was used for structure identification for this type of acetoacetate for the first time.

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Santoro, Ilaria, Monica Nardi, Cinzia Benincasa, Paola Costanzo, Girolamo Giordano, Antonio Procopio et Giovanni Sindona. « Sustainable and Selective Extraction of Lipids and Bioactive Compounds from Microalgae ». Molecules 24, n^o 23 (28 novembre 2019) : 4347. http://dx.doi.org/10.3390/molecules24234347.

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The procedures for the extraction and separation of lipids and nutraceutics from microalgae using classic solvents have been frequently used over the years. However, these production methods usually require expensive and toxic solvents. Based on our studies involving the use of eco-sustainable methodologies and alternative solvents, we selected ethanol (EtOH) and cyclopentyl methyl ether (CPME) for extracting bio-oil and lipids from algae. Different percentages of EtOH in CPME favor the production of an oil rich in saturated fatty acids (SFA), useful to biofuel production or rich in bioactive compounds. The proposed method for obtaining an extract rich in saturated or unsaturated fatty acids from dry algal biomass is disclosed as eco-friendly and allows a good extraction yield. The method is compared both in extracted oil percentage yield and in extracted fatty acids selectivity to extraction by supercritical carbon dioxide (SC-CO2).

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Sonnabend, Maresa, Suzanne G. Aubin, Annette M. Schmidt et Marc C. Leimenstoll. « Sophorolipid-Based Oligomers as Polyol Components for Polyurethane Systems ». Polymers 13, n^o 12 (18 juin 2021) : 2001. http://dx.doi.org/10.3390/polym13122001.

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Due to reasons of sustainability and conservation of resources, polyurethane (PU)-based systems with preferably neutral carbon footprints are in increased focus of research and development. The proper design and development of bio-based polyols are of particular interest since such polyols may have special property profiles that allow the novel products to enter new applications. Sophorolipids (SL) represent a bio-based toolbox for polyol building blocks to yield diverse chemical products. For a reasonable evaluation of the potential for PU chemistry, however, further investigations in terms of synthesis, derivatization, reproducibility, and reactivity towards isocyanates are required. It was demonstrated that SL can act as crosslinker or as plasticizer in PU systems depending on employed stoichiometry. (ω-1)-hydroxyl fatty acids can be derived from SL and converted successively to polyester polyols and PU. Additionally, (ω-1)-hydroxyl fatty acid azides can be prepared indirectly from SL and converted to A/B type PU by Curtius rearrangement.

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Bahadi, Murad, Jumat Salimon et Darﬁzzi Derawi. « Synthesis of ISO Grade 46 and 68 Biolubricant from Palm Kernel Fatty Acids ». Sains Malaysiana 51, n^o 8 (31 août 2021) : 2507–29. http://dx.doi.org/10.17576/jsm-2022-5108-13.

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Bio-based lubricant is crucial to be developed considering the toxicity risk, climate change, energy security, and green-environmental approach. Palm kernel fatty acids based biolubricants were synthesized by the homogeneous acid-catalyzed esterification reaction between palm kernel fatty acids with selected polyhydric alcohols; trimethylolpropane (TMP), di-trimethylolpropane (Di-TMP), and pentaerythritol (PE). The reaction optimization is done using a D-optimal design based on four parameters; the ratio of reactants, reaction time, reaction temperature, and catalyst loading. The optimum yield range between 80 and 87%, with more than 93% the selectivity of biolubricant products. The chemical structures of synthesized Palm kernel fatty acids-based biolubricants were characterized and confirmed using FTIR, NMR (1H and 13C) spectroscopies, and GC-FID chromatography. The FTIR spectra of palm kernel fatty acids-based biolubricants products clearly showed the peaks of C=O and C–O of the ester group at 1741-1740 cm-1 and 1234-1152 cm-1, respectively. Furthermore, 1H NMR spectra confirmed the ester group's proton chemical shift (-CH2-O-) at 3.96-4.11 ppm. The 13C NMR spectra confirmed the carbon chemical shifts of ester carbonyl (C=O) signals at 173.5-173.2 ppm. The results for lubrication properties have shown that the palm kernel fatty acids based biolubricants have low-temperature properties with pour points value in the range of -5 to -10 °C, a high flash point of 320-360 °C, a high viscosity index (VI) of 140.86-154.8, the kinematic viscosity of 41.76-87.06 cSt (40 °C), 8.73-14.77 cSt (100 °C), and thermal stability over 210 °C. All synthetic lubricants are categorized as ISO 46 (TMP triester) and ISO 68 (Di-TMP tetraester and PE tetraester).

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Botturi, Alice, Federico Battista, Marco Andreolli, Filippo Faccenda, Salvatore Fusco, David Bolzonella, Silvia Lampis et Nicola Frison. « Polyhydroxyalkanoated-Rich Microbial Cells from Bio-Based Volatile Fatty Acids as Potential Ingredient for Aquaculture Feed ». Energies 14, n^o 1 (23 décembre 2020) : 38. http://dx.doi.org/10.3390/en14010038.

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In this study, the production of polyhydroxyalkanoated PHA-rich microbial biomass as a novel feed additive in aquaculture was investigated at a lab-scale. Bio-based volatile fatty acids (VFAs), obtained from the acidogenic fermentation of agricultural residues in existing anaerobic digestion plants, were used as carbon and energy to cultivate the PHA-rich microbial biomass. The experimental activities were carried out using Thauera sp. Sel9 as pure strain, which was grown in a continuous stirred-tank reactor (CSTR) operated at three different hydraulic retention times (HRT). The highest productivity obtained of biomass cells was 0.69 g/L day, operating at one day HRT while the observed PHAs production yield was 0.14 gPHA/g soluble COD removed. At these conditions, the PHA concentration in the microbial cells was 41%. Although the sulfur amino acids were available at high concentrations and above the typical concentration found in fishmeal, the amino acids profile of the obtained biomass revealed a lack of histidine and threonine. A preliminary economic analysis showed that the production of a novel source of feed additive from the conversion of agro-residues could give higher benefits in terms of revenues compared to the production of biogas production through anaerobic digestion.

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Ionescu, Mihail, et Zoran Petrovic. « Phenolation of vegetable oils ». Journal of the Serbian Chemical Society 76, n^o 4 (2011) : 591–606. http://dx.doi.org/10.2298/jsc100820050i.

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Novel bio-based compounds containing phenols suitable for the synthesis of polyurethanes were prepared. The direct alkylation of phenols with different vegetable oils in the presence of superacids (HBF4, triflic acid) as catalysts was studied. The reaction kinetics was followed by monitoring the decrease of the double bond content (iodine value) with time. In order to understand the mechanism of the reaction, phenol was alkylated with model compounds. The model compounds containing one internal double bond were 9-octadecene and methyl oleate and those with three double bonds were triolein and high oleic safflower oil (82% oleic acid). It was shown that the best structures for phenol alkylation are fatty acids with only one double bond (oleic acid). Fatty acids with two double bonds (linoleic acid) and three double bonds (linolenic acid) lead to polymerized oils by a Diels Alder reaction, and to a lesser extent to phenol alkylated products. The reaction product of direct alkylation of phenol with vegetable oils is a complex mixture of phenol alkylated with polymerized oil (30-60%), phenyl esters formed by transesterification of phenol with triglyceride ester bonds (<10 %) and unreacted oil (30%). The phenolated vegetable oils are new aromatic-aliphatic bio-based raw materials suitable for the preparation of polyols (by propoxylation, ethoxylation, Mannich reactions) for the preparation of polyurethanes, as intermediates for phenolic resins or as bio-based antioxidants.

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Santos-Merino, María, Raquel Gutiérrez-Lanza, Juan Nogales, José Luis García et Fernando de la Cruz. « Synechococcus elongatus PCC 7942 as a Platform for Bioproduction of Omega-3 Fatty Acids ». Life 12, n^o 6 (29 mai 2022) : 810. http://dx.doi.org/10.3390/life12060810.

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Alpha-linolenic acid and stearidonic acid are precursors of omega-3 polyunsaturated fatty acids, essential nutrients in the human diet. The ability of cyanobacteria to directly convert atmospheric carbon dioxide into bio-based compounds makes them promising microbial chassis to sustainably produce omega-3 fatty acids. However, their potential in this area remains unexploited, mainly due to important gaps in our knowledge of fatty acid synthesis pathways. To gain insight into the cyanobacterial fatty acid biosynthesis pathways, we analyzed two enzymes involved in the elongation cycle, FabG and FabZ, in Synechococcus elongatus PCC 7942. Overexpression of these two enzymes led to an increase in C18 fatty acids, key intermediates in omega-3 fatty acid production. Nevertheless, coexpression of these enzymes with desaturases DesA and DesB from Synechococcus sp. PCC 7002 did not improve alpha-linolenic acid production, possibly due to their limited role in fatty acid synthesis. In any case, efficient production of stearidonic acid was not achieved by cloning DesD from Synechocystis sp. PCC 6803 in combination with the aforementioned DesA and DesB, reaching maximum production at 48 h post induction. According to current knowledge, this is the first report demonstrating that S. elongatus PCC 7942 can be used as an autotrophic chassis to produce stearidonic acid.

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Mollica, Fabio, Marco Lucarini, Cinzia Passerini, Claudio Carati, Silvia Pavoni, Lucia Bonoldi et Riccardo Amorati. « Effect of Antioxidants on High-Temperature Stability of Renewable Bio-Oils Revealed by an Innovative Method for the Determination of Kinetic Parameters of Oxidative Reactions ». Antioxidants 9, n^o 5 (8 mai 2020) : 399. http://dx.doi.org/10.3390/antiox9050399.

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Bio-oils employed for various industrial purposes, such as biodiesel production, undergo extensive oxidation and degradation during transformation processes. Therefore, it is extremely important to predict their stability at high temperature. We report herein a new procedure based on the optically detected profile of headspace O2 concentration during isotherms at 130 °C for evaluating the oxidation kinetic parameters of several bio-oil feedstocks. The slope of O2 consumption and the induction period duration were related to the oil characteristics (molecular structure, acidity, and presence of intrinsic antioxidants or metals). The increase of the induction time caused by a standardized propyl gallate addition yielded a semiquantitative value of radical generation rate. Investigated oils included used cooking oils; mono-, di-, and triglycerides from natural sources; free fatty acids; transesterified oils; and their blends. With respect to other methods, this characterization presents the advantage of disentangling and evaluating the role of both fatty acids composition and naturally occurring antioxidants, and allows the development of rational strategies for antioxidant protection of oils and of their blends.

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Ferreira, Raphael, Paulo Gonçalves Teixeira, Verena Siewers et Jens Nielsen. « Redirection of lipid flux toward phospholipids in yeast increases fatty acid turnover and secretion ». Proceedings of the National Academy of Sciences 115, n^o 6 (22 janvier 2018) : 1262–67. http://dx.doi.org/10.1073/pnas.1715282115.

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Bio-based production of fatty acids and fatty acid-derived products can enable sustainable substitution of petroleum-derived fuels and chemicals. However, developing new microbial cell factories for producing high levels of fatty acids requires extensive engineering of lipid metabolism, a complex and tightly regulated metabolic network. Here we generated a Saccharomyces cerevisiae platform strain with a simplified lipid metabolism network with high-level production of free fatty acids (FFAs) due to redirected fatty acid metabolism and reduced feedback regulation. Deletion of the main fatty acid activation genes (the first step in β-oxidation), main storage lipid formation genes, and phosphatidate phosphatase genes resulted in a constrained lipid metabolic network in which fatty acid flux was directed to a large extent toward phospholipids. This resulted in simultaneous increases of phospholipids by up to 2.8-fold and of FFAs by up to 40-fold compared with wild-type levels. Further deletion of phospholipase genes PLB1 and PLB2 resulted in a 46% decrease in FFA levels and 105% increase in phospholipid levels, suggesting that phospholipid hydrolysis plays an important role in FFA production when phospholipid levels are increased. The multiple deletion mutant generated allowed for a study of fatty acid dynamics in lipid metabolism and represents a platform strain with interesting properties that provide insight into the future development of lipid-related cell factories.

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Huang, Kun, Xuetong Fan, Richard Ashby et Helen Ngo. « Structure-activity relationship of antibacterial bio-based epoxy polymers made from phenolic branched fatty acids ». Progress in Organic Coatings 155 (juin 2021) : 106228. http://dx.doi.org/10.1016/j.porgcoat.2021.106228.

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Nazari, Meysam, Mohamed Jebrane et Nasko Terziev. « Multicomponent bio-based fatty acids system as phase change material for low temperature energy storage ». Journal of Energy Storage 39 (juillet 2021) : 102645. http://dx.doi.org/10.1016/j.est.2021.102645.

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Da Ros, Cinzia, Vincenzo Conca, Anna Laura Eusebi, Nicola Frison et Francesco Fatone. « Sieving of municipal wastewater and recovery of bio-based volatile fatty acids at pilot scale ». Water Research 174 (mai 2020) : 115633. http://dx.doi.org/10.1016/j.watres.2020.115633.

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Campos Flexa Ribeiro Filho, Paulo Roberto, Matheus Rocha do Nascimento, Silvia Shelly Otaviano da Silva, Francisco Murilo Tavares de Luna, Enrique Rodríguez-Castellón et Célio Loureiro Cavalcante. « Synthesis and Frictional Characteristics of Bio-Based Lubricants Obtained from Fatty Acids of Castor Oil ». Lubricants 11, n^o 2 (31 janvier 2023) : 57. http://dx.doi.org/10.3390/lubricants11020057.

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The depletion of oil reserves and concerns about the environmental impact of the use and incorrect disposal of mineral lubricants have been promoting the development of bio-based lubricants. In this study, biolubricants obtained from fatty acids of castor oil were synthesized by esterification (>wt.%93), epoxidation (>wt.%92), and oxirane ring opening reactions using water (>wt.%92) or 2-ethylhexanol (>wt.%94) as nucleophilic agents. The frictional characteristics of the synthesized samples were obtained through tribological tests performed in a four-ball tester and compared with a commercial mineral oil. The sample obtained through oxirane ring opening with water showed the best frictional performance (FC = 0.0699 ± 0.0007) among the prepared samples, with equivalent wear rate (WSD = 281.2 ± 5.54 μm) and ca. 20% lower friction coefficient when compared to the commercial mineral oil, indicating its great potential for replacing mineral fossil oils.

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Burelo, Manuel, Araceli Martínez, Josué David Hernández-Varela, Thomas Stringer, Monserrat Ramírez-Melgarejo, Alice Y. Yau, Gabriel Luna-Bárcenas et Cecilia D. Treviño-Quintanilla. « Recent Developments in Synthesis, Properties, Applications and Recycling of Bio-Based Elastomers ». Molecules 29, n^o 2 (12 janvier 2024) : 387. http://dx.doi.org/10.3390/molecules29020387.

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In 2021, global plastics production was 390.7 Mt; in 2022, it was 400.3 Mt, showing an increase of 2.4%, and this rising tendency will increase yearly. Of this data, less than 2% correspond to bio-based plastics. Currently, polymers, including elastomers, are non-recyclable and come from non-renewable sources. Additionally, most elastomers are thermosets, making them complex to recycle and reuse. It takes hundreds to thousands of years to decompose or biodegrade, contributing to plastic waste accumulation, nano and microplastic formation, and environmental pollution. Due to this, the synthesis of elastomers from natural and renewable resources has attracted the attention of researchers and industries. In this review paper, new methods and strategies are proposed for the preparation of bio-based elastomers. The main goals are the advances and improvements in the synthesis, properties, and applications of bio-based elastomers from natural and industrial rubbers, polyurethanes, polyesters, and polyethers, and an approach to their circular economy and sustainability. Olefin metathesis is proposed as a novel and sustainable method for the synthesis of bio-based elastomers, which allows for the depolymerization or degradation of rubbers with the use of essential oils, terpenes, fatty acids, and fatty alcohols from natural resources such as chain transfer agents (CTA) or donors of the terminal groups in the main chain, which allow for control of the molecular weights and functional groups, obtaining new compounds, oligomers, and bio-based elastomers with an added value for the application of new polymers and materials. This tendency contributes to the development of bio-based elastomers that can reduce carbon emissions, avoid cross-contamination from fossil fuels, and obtain a greener material with biodegradable and/or compostable behavior.

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Santoro, Orlando, Lorella Izzo et Francesco Della Monica. « Recent Advances in RO(CO)P of Bio-Based Monomers ». Sustainable Chemistry 3, n^o 2 (31 mai 2022) : 259–85. http://dx.doi.org/10.3390/suschem3020017.

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Synthetic polymers have a key role in modern society as they have allowed for great technological advancement since their discovery. However, the use of fossil-fuel-based raw materials and the pollution derived from plastics accumulation in the environment raised enormous concern, driving research efforts toward the identification of more sustainable alternatives. Bio-based functional molecules susceptible to ring-opening (co)polymerisation [RO(C)OP], such as lactones, cyclic carbonates, and oxiranes, represent an attractive source of monomers for the synthesis of more sustainable polymers. In this review, we describe the main advancement in this research field reported during the last seven years. In particular, we describe the preparation of monomers from (renewable) bio-sources such as sugars, terpenes, fatty acids, and carbon dioxide with a focus on structurally novel substrates. Both metal-mediated and organo-catalytic RO(CO)P methods are described, and the properties of derived functional polymers are discussed when relevant.

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Hamza, Hammadi, Walid Elfalleh et Kameleddine Nagaz. « Date Palm Seed Oil (Phoenix dactylifera L.) Green Extraction : Physicochemical Properties, Antioxidant Activities, and Phenolic and Fatty Acid Profiles ». Journal of Food Quality 2021 (6 octobre 2021) : 1–9. http://dx.doi.org/10.1155/2021/2394220.

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Date palm seed oil is among the precious vegetable oils with low yield, whose extraction is commonly done with organic solvents which cause serious problems. This study aims to assess the effectiveness of orange peel essential oil as biosolvent for date seed oil extraction. Green extraction was conducted by Soxhlet apparatus as well as by soaking and compared with the Soxhlet method using petroleum ether. The GC-MS analysis of orange peel essential oil confirmed its richness with limonene (94.31%), which justifies its usefulness as green solvent. The latter gave higher yields, the extracted bio-oil was light brown with pleasant odor, and the characteristics were consistent with international standards. Based on the GC profiles, obtained oils were similar using both solvents, and the major compounds were oleic and lauric acids. The bio-oil phenolic content and the antioxidant activity were high, and the major compounds were the protocatechuic, chlorogenic, and 4-O-caffeoylquinic acids. Gallic and p -coumaric acids were the major compounds for oil extracted by petroleum ether.

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Yoon, Jung-Hoon, Jong Hyun Choi, So-Jung Kang, Nack-Shick Choi, Jung-Sook Lee et Jae Jun Song. « Jeongeupia naejangsanensis gen. nov., sp. nov., a cellulose-degrading bacterium isolated from forest soil from Naejang Mountain in Korea ». International Journal of Systematic and Evolutionary Microbiology 60, n^o 3 (1 mars 2010) : 615–19. http://dx.doi.org/10.1099/ijs.0.012591-0.

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A Gram-stain-negative, motile, rod-shaped, cellulose-degrading bacterial strain, BIO-TAS4-2T, which belongs to the Betaproteobacteria, was isolated from forest soil from Naejang Mountain, Korea, and its taxonomic position was investigated by using a polyphasic study. Strain BIO-TAS4-2T grew optimally at pH 7.0–8.0, at 30 °C and in the presence of 0–1.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences showed that strain BIO-TAS4-2T clustered with members of the genera Andreprevotia, Silvimonas and Deefgea of the family Neisseriaceae, with which it exhibited 16S rRNA gene sequence similarities of 93.5–94.2 %. Strain BIO-TAS4-2T contained Q-8 as the predominant ubiquinone and summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH) and C16 : 0 as the major fatty acids. The DNA G+C content was 63.8 mol%. Strain BIO-TAS4-2T could be differentiated from members of phylogenetically related genera by differences in fatty acid composition, DNA G+C content and some phenotypic properties. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain BIO-TAS4-2T is considered to represent a novel species in a new genus, for which the name Jeongeupia naejangsanensis gen. nov., sp. nov. is proposed, with BIO-TAS4-2T (=KCTC 22633T=CCUG 57610T) as the type strain.

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Gao, Cheng-Long, Xin Wang, Hong-Ze Gang, Jin-Feng Liu, Bo-Zhong Mu et Shi-Zhong Yang. « The optimization of heterogeneous catalytic conditions in the direct alkylation of waste vegetable oil ». Royal Society Open Science 7, n^o 7 (juillet 2020) : 192254. http://dx.doi.org/10.1098/rsos.192254.

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Alkylated waste vegetable oil is a versatile intermediate product in the synthesis of bio-based materials. Heterogeneous catalytic condition with high conversion rate in the direct alkylation of waste vegetable oil was reported and the deactivation mechanism of catalyst was revealed. The total exchange capacity, elemental composition and pyrolysis product of catalyst before and after the alkylation reaction were analysed by back titration, elemental analysis, electrospray ionization mass spectrometry, gas chromatography mass spectrometry and pyrolysis-gas chromatography/mass spectrometry, respectively. The results indicated that the metallic and non-metallic (C, H) elements contents of the catalyst have very much increased with great changes in pyrolysis product and a slight decrease in the total exchange capacity. The formation of insoluble polymers through Diels–Alder cycloaddition between triglycerides was proved to be the major factor causing the dysfunction of the catalytic centre. The metal ions from corrosion of the reactor were the minor factor causing about 2.56% loss of the catalytic centre. Moreover, the catalyst was able to maintain high catalytic efficiency when replacing the raw materials with other waste vegetable oil having low concentration of polyunsaturated fatty acids, which is significant for producing not only the aryl fatty acids derivatives but also the bio-based surfactants.

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Boutry-Regard, Claire, Gerard Vinyes-Parés, Denis Breuillé et Toshio Moritani. « Supplementation with Whey Protein, Omega-3 Fatty Acids and Polyphenols Combined with Electrical Muscle Stimulation Increases Muscle Strength in Elderly Adults with Limited Mobility : A Randomized Controlled Trial ». Nutrients 12, n^o 6 (23 juin 2020) : 1866. http://dx.doi.org/10.3390/nu12061866.

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Age-related sarcopenia is a progressive and generalized skeletal muscle disorder associated with adverse outcomes. Herein, we evaluate the effects of a combination of electrical muscle stimulation (EMS) and a whey-based nutritional supplement (with or without polyphenols and fish oil-derived omega-3 fatty acids) on muscle function and size. Free-living elderly participants with mobility limitations were included in this study. They received 2 sessions of EMS per week and were randomly assigned to ingest an isocaloric beverage and capsules for 12 weeks: (1) carbohydrate + placebo capsules (CHO, n = 12), (2) whey protein isolate + placebo capsules (WPI, n = 15) and (3) whey protein isolate + bioactives (BIO) capsules containing omega-3 fatty acids, rutin, and curcumin (WPI + BIO, n = 10). The change in knee extension strength was significantly improved by 13% in the WPI + BIO group versus CHO on top of EMS, while WPI alone did not provide a significant benefit over CHO. On top of this, there was the largest improvement in gait speed (8%). The combination of EMS and this specific nutritional intervention could be considered as a new approach for the prevention of sarcopenia but more work is needed before this approach should be recommended. This trial was registered at the Japanese University Hospital Medical Information Network (UMIN) clinical trial registry (UMIN000008382).

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Kolář, Martin, Jana Machotová, Martin Hájek, Jan Honzíček, Tomáš Hájek et Štěpán Podzimek. « Application of Vegetable Oil-Based Monomers in the Synthesis of Acrylic Latexes via Emulsion Polymerization ». Coatings 13, n^o 2 (22 janvier 2023) : 262. http://dx.doi.org/10.3390/coatings13020262.

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In this work, two bio-based raw materials, rapeseed oil and technical-grade oleic acid, were modified to yield acrylated monomers. Polymeric latexes designed for coating applications were synthesized using emulsion polymerization. Methyl methacrylate and butyl acrylate were copolymerized with various ratios of the acrylated bio-based monomers (0–20 wt. % in the monomer mixture). The polymerization with high monomer conversion and low coagulum content was successfully performed up to the content of 15 wt. % of the bio-based monomers, leading to long-term stable latexes. The asymmetric flow field flow fractionation coupled with a multi-angle light scattering detector was used to describe the molar mass distribution of the synthesized copolymers. Ultra-high molar mass fractions were detected in copolymers comprising the bio-based monomers due to the presence of multi-acrylated bio-based ingredients originating from linoleic and linolenic fatty acids. This phenomenon became more pronounced for the rapeseed oil-originated monomer. The prepared latexes comprising copolymerized bio-based monomers showed comparable or even better coating performance in terms of gloss and water resistance in comparison with the reference acrylic coating, which makes the acrylated vegetable oil-based monomers attractive for the manufacturing of sustainable water-borne materials in the coating industry.

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Laurichesse, Stéphanie, Cédric Huillet et Luc Avérous. « Original polyols based on organosolv lignin and fatty acids : new bio-based building blocks for segmented polyurethane synthesis ». Green Chem. 16, n^o 8 (2014) : 3958–70. http://dx.doi.org/10.1039/c4gc00596a.

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