3681-78-5Relevant articles and documents
Tunable aryl imidazolium ionic liquids (TAIILs) as environmentally benign catalysts for the esterification of fatty acids to biodiesel fuel
Ho, Wen-Yueh,Lin, Wesley,Lin, Yi-Jyun,Luo, Shun-Yuan,Pantawane, Amit,Su, Po-Fang,Thul, Mayur,Tseng, Shao-An,Wu, Hsin-Ru
, (2020/12/02)
Herein, we describe the synthesis of tunable aryl imidazolium ionic liquid catalysts and tested for esterification of fatty acids to biodiesel. In this work, six tunable aryl imidazolium ionic liquids (TAIILs) 1a-1f were prepared. These ionic liquids were used as the economical and reusable catalysts for the synthesis of biodiesel fuels. The reaction has been preceded in a monophase at 80 °C for 4 h, after which the product was separated from the catalyst system by a simple liquid/liquid phase separation at room temperature with excellent yields. With the simple post-process, the catalyst is reusable at least 6 times. This novel method offers a short reaction time, good yields, and environmentally benign characteristics.
Electrophysiological responses of bactrocera kraussi (Hardy) (tephritidae) to rectal gland secretions and headspace volatiles emitted by conspecific males and females
Holgate, Danielle,Jamie, Ian M.,Jamie, Joanne F.,Mendez, Vivian,Noushini, Sally,Park, Soo Jean,Perez, Jeanneth,Taylor, Phillip W.
, (2021/08/27)
Pheromones are biologically important in fruit fly mating systems, and also have potential applications as attractants or mating disrupters for pest management. Bactrocera kraussi (Hardy) (Diptera: Tephritidae) is a polyphagous pest fruit fly for which the chemical profile of rectal glands is available for males but not for females. There have been no studies of the volatile emissions of either sex or of electrophysiological responses to these compounds. The present study (i) establishes the chemical profiles of rectal gland contents and volatiles emitted by both sexes of B. kraussi by gas chromatography–mass spectrometry (GC–MS) and (ii) evaluates the detection of the identified compounds by gas chromatography–electroantennogram detection (GC–EAD) and –electropalpogram detection (GC–EPD). Sixteen compounds are identified in the rectal glands of male B. kraussi and 29 compounds are identified in the rectal glands of females. Of these compounds, 5 were detected in the headspace of males and 13 were detected in the headspace of females. GC–EPD assays recorded strong signals in both sexes against (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, 2-ethyl-7-mehtyl-1,6-dioxaspiro[4.5]decane isomer 2, (E,Z)/(Z,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, and (Z,Z)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane. Male antennae responded to (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, 2-methyl-6-pentyl-3,4-dihydro-2H-pyran, 6-hexyl-2-methyl-3,4-dihydro-2H-pyran, 6-oxononan-1-ol, ethyl dodecanoate, ethyl tetradecanoate and ethyl (Z)-hexadec-9-enoate, whereas female antennae responded to (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane and 2-methyl-6-pentyl-3,4-dihydro-2H-pyran only. These compounds are candidates as pheromones mediating sexual interactions in B. kraussi.
A Fed-Batch Synthetic Strategy for a Three-Step Enzymatic Synthesis of Poly-?-caprolactone
Scherkus, Christian,Schmidt, Sandy,Bornscheuer, Uwe T.,Gr?ger, Harald,Kara, Selin,Liese, Andreas
, p. 3446 - 3452 (2016/11/28)
A three-step enzymatic reaction sequence for the synthesis of poly-?-caprolactone (PCL) was designed running in a fed-batch operation. The first part of the cascade consisted of two oxidation steps starting with alcohol dehydrogenase catalyzed oxidation from cyclohexanol to cyclohexanone and further oxidation to ?-caprolactone (ECL) by means of a Baeyer–Villiger monooxygenase. As a third step, lipase-catalyzed hydrolysis of the lactone to 6-hydroxyhexanoic acid (6-HHA) was designed. With this biocatalytic multistep process reported herein, severe substrate surplus and product inhibition could be circumvented by the fed-batch operation by adding the cyclohexanol substrate and by in situ product removal of ECL by hydrolysis, respectively. Up to 283 mm product concentration of 6-HHA was reached in the fed-batch operated process without loss in productivity within 20 h. After extraction and subsequent polymerization catalyzed by Candida antarctica lipase B, analysis of the unfractionated polymer revealed a bimodal distribution of the polymer population, which reached a mass average molar mass (Mw) value of approximately 63 000 g mol?1 and a dispersity (Mw/Mn) of 1.1 for the higher molecular weight population, which thus revealed an alternative route to the conventional synthesis of PCL.
Immobilization of lipase on biocompatible co-polymer of polyvinyl alcohol and chitosan for synthesis of laurate compounds in supercritical carbon dioxide using response surface methodology
Badgujar, Kirtikumar C.,Bhanage, Bhalchandra M.
, p. 1224 - 1236 (2015/07/08)
Biocompatible co-polymer matrix has great importance for enzyme immobilization and subsequent biocatalytic applications to synthesize important organic moieties. Citronellyl laurate is a fatty-acid-ester having pleasant fruity aroma and widely used as/in emulsifier, lubricant in textile, paint or ink-additives, surfactants, perfumery and food-flavouring ingredient. In present study, Burkholderia cepacia lipase (BCL) was immobilized on biodegradable co-polymer of chitosan (CHI) and polyvinyl alcohol (PVA). The synthesized bio-catalyst {PVA:CHI:BCL (6:4:2.5)} was characterized by SEM, TGA, lipase assay and protein-content analysis. This biocatalyst was applied to synthesize citronellyl laurate in supercritical carbon-dioxide (SC-CO2) using response surface methodology with five-factor-three-level Box-Behnken-design to optimize reaction parameters (citronellol: 8.5 mmol; vinyl laurate: 19.87 mmol; biocatalyst: 175.6 mg; temperature: 46.02 °C; pressure: 8.81 MPa) which provided 94 ± 1.52% yield. The protocol is extended to synthesize various important 12 laurate compounds with excellent yield (90-98%) and noteworthy recyclability (upto studied 5 recycles). Interestingly, immobilized PVA/CHI/lipase biocatalyst showed 4-fold higher bio-catalytic activity than free lipase in SC-CO2. Moreover, the biocatalyst activity assessment study showed remarkable activity-stability of immobilized biocatalyst in SC-CO2 media as compared to free enzyme. Thus, present protocol demonstrated potential biocatalytic applications for synthesis of important laurate compounds with excellent recyclability in SC-CO2 as greener biocatalyst and reaction medium.
METHOD FOR CONTINUOUSLY PREPARING CARBOXYLIC ACID ESTER
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Paragraph 0024; 0026, (2013/11/19)
A method for continuously preparing a carboxylic acid ester is disclosed. In the method of the present invention, a vertical reactor is filled with a solid catalyst, a carboxylic acid and an alcohol are introduced into a lower part of the vertical reactor, esterification is performed to form an esterized mixture, the esterized mixture is output from an upper part of the vertical reactor, and distillation is performed to isolate the carboxylic acid ester. The method of the present invention is simple, easily controlled and environmental friendly, and has significantly high conversion rate and selectivity.
Poly(3-hydroxyoctanoate) depolymerase from Pseudomonas fluorescens GK13: Catalysis of ester-forming reactions in non-aqueous media
Santos, Marta,Gangoiti, Joana,Llama, Maria J.,Serra, Juan L.,Keul, Helmut,Moeller, Martin
experimental part, p. 81 - 86 (2012/06/29)
Several industrial processes based on lipase catalysis have been established. However, since there are still a vast number of catalytic processes that lack a suitable enzyme, the discovery of new biocatalysts is required to fulfil this purpose. The potential of using the medium-chain-length (mcl)-PHA depolymerase from Pseudomonas fluorescens GK13 in anhydrous media to catalyze ester-forming reactions has been investigated and compared with that of Novozyme 435. The mcl-PHA depolymerase catalyzes the ring-opening polymerization of racemic β-butyrolactone (β-BL), l- and d-lactide (LLA, DLA) with high yield resulting in low molecular weight polymers. On the other hand, ε-caprolactone and pentadecalactone, which show high polymerizability using Novozyme 435 as catalyst, were not polymerized by mcl-PHA depolymerase. Besides, the activity of mcl-PHA depolymerase toward transesterification and esterification of ethyl-3-hydroxyoctanoate, lauric acid, (R,S)-β-BL, LLA and DLA has been studied.
Specific enzyme-catalyzed hydrolysis and synthesis in aqueous and organic medium using biocatalysts with lipase activity from Aspergillus niger MYA 135
Romero, Cintia M.,Pera, Licia M.,Loto, Flavia,Baigori, Mario D.
, p. 1361 - 1368 (2013/01/15)
In the present study, the specific hydrolytic activity of three biocatalysts such as the constitutive mycelium-bound lipase, the induced mycelium-bound lipase and the lyophilized induced supernatant from A. niger MYA 135 was evaluated in both aqueous and organic media.A direct correlation between activity in water and n-hexane was not observed for the same hydrolytic reaction. The n-hexane/water activity ratio (RO/A) was applied to characterize the activity in organic medium. The three biocatalysts showed RO/A values higher than 1 for hydrolysis of long-chain fatty acid esters, demonstrating a higher specific hydrolytic activity in organic solvent than in water. A different behavior was observed during hydrolysis of middle-chain fatty acid esters, which was higher in aqueous medium (R O/Adw) observed in a reaction mixture containing propanol and p-nitrophenyl laurate. Finally, both p-nitrophenyl caprate (C10) and p-nitrophenyl laurate (C12) were preferentially methanolized by the lyophilized induced supernatant, being this lipase activity the most specific biocatalyst preparation under transesterification conditions. A selectivity-based analysis of each lipase preparation toward transesterification or hydrolysis in organic medium was evaluated as well. Springer Science+Business Media, LLC 2012.
Dodecanoic acid derivatives: Synthesis, antimicrobial evaluation and development of one-target and multi-target QSAR models
Sarova, Devinder,Kapoor, Archana,Narang, Rakesh,Judge, Vikramjeet,Narasimhan, Balasubramanian
experimental part, p. 769 - 781 (2012/05/20)
In this study a series of dodecanoic acid derivatives (1-30) were synthesized and evaluated for in vitro antimicrobial activity against the panel of Gram positive, Gram negative bacterial and fungal strains. 4-Nitro phenyl dodecanoate (4) and quinolin-8-yl dodecanoate (5) emerged as most effective antibacterial agents, and 1-(4-benzylpiperazin- 1-yl) dodecan-1-one (15) was found to be the most effective antifungal agent amongst the synthesized dodecanoic acid derivatives. Quantitative structure activity relationship (QSAR) studies performed by the development of one-target and multi-target models indicated that multitarget model was effective in describing the antimicrobial activity of dodecanoic acid derivatives as well demonstrated the importance of topological parameter, zero-order molecular connectivity index (0X). Springer Science+Business Media, LLC 2010.
Enabling industrial biocatalytic processes by application of silicone-coated enzyme preparations
Nieguth,Eckstein,Wiemann,Thum,Ansorge-Schumacher
experimental part, p. 2522 - 2528 (2011/11/29)
Composite particles of the commercial lipase preparation NZ435 and silicone (silcoat-NZ435) have recently been described as promising biocatalysts for synthetic use. In this study, their actual potential for enhanced performance in industrial applications was evaluated, focusing on scenarios where carrier disintegration and catalyst leaching constitute key limitations. All three investigated model reactions, the syntheses of myristyl myristate, poly(ethylene glycol) 400-coconut fatty acid monoester and ethylene oxide and propylene oxide copolymer (EO/PO)-oleic acid diester, were considerably improved in terms of the maximal number of reaction cycles performed with the same batch of catalyst, and consequently in terms of the obtainable product amount. The total turnover numbers (TTN) increased by a factor up to 50, making the realization of this type of reactions in an industrial process more feasible. The utility of silcoat-NZ435 for stereoselective transformations was demonstrated with the enantioselective acylation of 1-phenylethanol with vinyl butyrate, in which full retention of the excellent stereoselectivity of native NZ435 was observed. Moreover, it was demonstrated for the first time that the methodology by which silcoat-catalysts are obtained can be successfully transferred to alternative carriers and enzymes (e.g., protease, esterase and laccase), opening a broad field for the implementation and advancement of biocatalysis in industrial processes. Copyright
Solid acid catalysts for biodiesel production - Towards sustainable energy
Kiss, Anton A.,Dimian, Alexandre C.,Rothenberg, Gadi
, p. 75 - 81 (2007/10/03)
The advantages of biodiesel as an alternative fuel and the problems involved in its manufacturing are outlined. The pros and cons of making biodiesel via fatty acid esterification using solid acid catalysts are examined. The main problem is finding a suitable catalyst that is active, selective, and stable under the process conditions. Various solid acids (zeolites, ion-exchange resins, and mixed metal oxides) are screened as catalysts in the esterification of dodecanoic acid with 2-ethylhexanol, 1-propanol, and methanol at 130-180°C. The most promising candidate is found to be sulphated zirconia. The catalyst's stability towards thermal decomposition and leaching is tested and the effects of the surface composition and structure on the catalytic activity are discussed.