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Ramírez N, Ubilla C, Campos J, Valencia F, Aburto C, Vera C, Illanes A, Guerrero C. Enzymatic production of lactulose by fed-batch and repeated fed-batch reactor. BIORESOURCE TECHNOLOGY 2021; 341:125769. [PMID: 34416660 DOI: 10.1016/j.biortech.2021.125769] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
The effects of the most significant operational variables on reactor performance of fed-batch and repeated fed-batch were evaluated in the lactulose production by enzymatic transgalactosylation. Feed flowrate in the fed stage (F) and fructose to lactose molar ratio (Fr/L) were the variables that mostly affected the values of lactulose yield (YLu), lactulose productivity (πLu) and selectivity of transgalactosylation (SLu/TOS). Maximum YLu of 0.21 g lactulose per g lactose was obtained at 50% w/w inlet carbohydrates concentration (IC) of, 50 °C, Fr/L 8, F 1 mL⋅min-1, 200 IU∙gLactose-1 reactor enzyme load and pH 4.5. At these conditions the selectivity was 7.4, productivity was 0.71 gLu∙g-1∙h-1and lactose conversion was 0.66. The operation by repeated fed batch increases the efficiency of use of the biocatalysts (EB) and the accumulated productivity compared to batch and fed batch operation with the same biocatalyst. EB obtained was 4.13 gLu∙mgbiocatalyst protein-1, 10.6 times higher than in fed-batch.
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Affiliation(s)
- Nicolás Ramírez
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile
| | - Claudia Ubilla
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile
| | - Javiera Campos
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile
| | - Francisca Valencia
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile
| | - Carla Aburto
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile
| | - Carlos Vera
- Department of Biology, Faculty of Chemistry and Biology, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Andrés Illanes
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile
| | - Cecilia Guerrero
- School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso (PUCV), Valparaíso, Chile.
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Gupta J, Agarwal M, Dalai A. An overview on the recent advancements of sustainable heterogeneous catalysts and prominent continuous reactor for biodiesel production. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2020.05.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Hosney H, Mustafa A. Semi-continuous Production of 2-Ethyl Hexyl Ester in a Packed Bed Reactor: Optimization and Economic Evaluation. J Oleo Sci 2020; 69:31-41. [PMID: 31902893 DOI: 10.5650/jos.ess19229] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The aim of this work was to investigate the technical as well as the economic feasibility of producing 2-ethyl hexyl oleate (2-EHO), a non-phthalate plasticizer in a solvent free medium. The esterification reaction between oleic acid and 2-ethyl hexyl alcohol was carried out in a packed bed reactor (PBR) using Candida antarctica lipase B (Novozym 435; Novozymes; Copenhagen-Denmark) as biocatalyst. RSM was employed to optimize the esterification reaction conditions. The optimum reaction conditions were found to be flow rate of 1.5 mL/min, No. of cycles of 12 and molar ratio of 4:1 2-ethyl hexanol to oleic acid. The maximum experimental and predicated conversions were found to be 95.8% and 95.61% respectively. Formation of 2-EHO was approved by FTIR, 1HNMR and 13CNMR. From the economic prospective, PBR was capable of producing 2-EHO with a purity of more than 94% over 480 h without remarkable reduction of enzyme activity. This revealed an economic production of 2-EHO at a yield of 2 tons kg-1 lipase. The manufacturing cost was found to be $ 1.88 /kg 2-EHO, this contributed to a profit of about 30% compared to the commercial price of 2-EHO. Such results approve the technical and economic feasibility for this sustainable method in esters production.
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Affiliation(s)
- Hadeel Hosney
- Chemical Engineering Department, Faculty of Engineering, Minia University.,Environmental Engineering program, Zewail City of Science and Technology
| | - Ahmad Mustafa
- Faculty of Engineering, October University for Modern Sciences and Arts.,Centre of Excellence, October University for Modern Sciences and Arts
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Abstract
Enzyme catalyzed reactions are rapidly becoming an invaluable tool for the synthesis of many active pharmaceutical ingredients. These reactions are commonly performed in batch, but continuous biocatalysis is gaining interest in industry because it would allow seamless integration of chemical and enzymatic reaction steps. However, because this is an emerging field, little attention has been paid towards the suitability of different reactor types for continuous biocatalytic reactions. Two types of continuous flow reactor are possible: continuous stirred tank and continuous plug-flow. These reactor types differ in a number of ways, but in this contribution, we focus on residence time distribution and how enzyme kinetics are affected by the unique mass balance of each reactor. For the first time, we present a tool to facilitate reactor selection for continuous biocatalytic production of pharmaceuticals. From this analysis, it was found that plug-flow reactors should generally be the system of choice. However, there are particular cases where they may need to be coupled with a continuous stirred tank reactor or replaced entirely by a series of continuous stirred tank reactors, which can approximate plug-flow behavior. This systematic approach should accelerate the implementation of biocatalysis for continuous pharmaceutical production.
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Jamil F, Al-Haj L, Al-Muhtaseb AH, Al-Hinai MA, Baawain M, Rashid U, Ahmad MN. Current scenario of catalysts for biodiesel production: a critical review. REV CHEM ENG 2017. [DOI: 10.1515/revce-2016-0026] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Due to increasing concerns about global warming and dwindling oil supplies, the world’s attention is turning to green processes that use sustainable and environmentally friendly feedstock to produce renewable energy such as biofuels. Among them, biodiesel, which is made from nontoxic, biodegradable, renewable sources such as refined and used vegetable oils and animal fats, is a renewable substitute fuel for petroleum diesel fuel. Biodiesel is produced by transesterification in which oil or fat is reacted with short chain alcohol in the presence of a catalyst. The process of transesterification is affected by the mode of reaction, molar ratio of alcohol to oil, type of alcohol, nature and amount of catalysts, reaction time, and temperature. Various studies have been carried out using different oils as the raw material; different alcohols (methanol, ethanol, butanol); different catalysts; notably homogeneous catalysts such as sodium hydroxide, potassium hydroxide, sulfuric acid, and supercritical fluids; or, in some cases, enzymes such as lipases. This article focuses on the application of heterogeneous catalysts for biodiesel production because of their environmental and economic advantages. This review contains a detailed discussion on the advantages and feasibility of catalysts for biodiesel production, which are both environmentally and economically viable as compared to conventional homogeneous catalysts. The classification of catalysts into different categories based on a catalyst’s activity, feasibility, and lifetime is also briefly discussed. Furthermore, recommendations have been made for the most suitable catalyst (bifunctional catalyst) for low-cost oils to valuable biodiesel and the challenges faced by the biodiesel industry with some possible solutions.
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Affiliation(s)
- Farrukh Jamil
- Department of Petroleum and Chemical Engineering , College of Engineering, Sultan Qaboos University , Muscat, 123 , Oman
| | - Lamya Al-Haj
- Department of Biology, College of Science , Sultan Qaboos University , Muscat 123 , Oman
| | - Ala’a H. Al-Muhtaseb
- Department of Petroleum and Chemical Engineering , College of Engineering, Sultan Qaboos University , Muscat, 123 , Oman
| | - Mohab A. Al-Hinai
- Department of Biology, College of Science , Sultan Qaboos University , Muscat 123 , Oman
| | - Mahad Baawain
- Department of Civil and Architectural Engineering , College of Engineering, Sultan Qaboos University , Muscat 123 , Oman
| | - Umer Rashid
- Institute of Advanced Technology, Universiti Putra Malaysia , 43400 UPM Serdang , Selangor-Malaysia
| | - Mohammad N.M. Ahmad
- Department of Chemical and Petroleum Engineering , Faculty of Engineering and Architecture, American University of Beirut , Beirut , Lebanon
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Canet A, Bonet-Ragel KÍ, Benaiges MD, Valero F. Biodiesel synthesis in a solvent-free system by recombinant Rhizopus oryzae: comparative study between a stirred tank and a packed-bed batch reactor. BIOCATAL BIOTRANSFOR 2017. [DOI: 10.1080/10242422.2016.1278211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Albert Canet
- Chemical Engineering Department, School of Engineering, Universitat Autònoma de Barcelona, Bellaterra Barcelona, Spain
| | - KÍrian Bonet-Ragel
- Chemical Engineering Department, School of Engineering, Universitat Autònoma de Barcelona, Bellaterra Barcelona, Spain
| | - M. Dolors Benaiges
- Chemical Engineering Department, School of Engineering, Universitat Autònoma de Barcelona, Bellaterra Barcelona, Spain
| | - Francisco Valero
- Chemical Engineering Department, School of Engineering, Universitat Autònoma de Barcelona, Bellaterra Barcelona, Spain
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7
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Ramos L, Martin LS, Santos JC, de Castro HF. Combined Use of a Two-Stage Packed Bed Reactor with a Glycerol Extraction Column for Enzymatic Biodiesel Synthesis from Macaw Palm Oil. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.6b03811] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Lucas Ramos
- Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12602-810, Brazil
| | - Lucas S. Martin
- Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12602-810, Brazil
| | - Júlio C. Santos
- Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12602-810, Brazil
| | - Heizir F. de Castro
- Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12602-810, Brazil
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8
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Enzymatic methanolysis reaction of canola oil using capillary channel reactor: Determination of the kinetic constants-involved. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.06.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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9
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Norjannah B, Ong HC, Masjuki HH, Juan JC, Chong WT. Enzymatic transesterification for biodiesel production: a comprehensive review. RSC Adv 2016. [DOI: 10.1039/c6ra08062f] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Biodiesel catalyzed by enzyme is affected by many factors. This review will critically discuss the three major components of enzymatic production of biodiesel and the methods used to improve the reaction.
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Affiliation(s)
- B. Norjannah
- Department of Mechanical Engineering
- Faculty of Engineering
- University of Malaya
- 50603 Kuala Lumpur
- Malaysia
| | - Hwai Chyuan Ong
- Department of Mechanical Engineering
- Faculty of Engineering
- University of Malaya
- 50603 Kuala Lumpur
- Malaysia
| | - H. H. Masjuki
- Department of Mechanical Engineering
- Faculty of Engineering
- University of Malaya
- 50603 Kuala Lumpur
- Malaysia
| | - J. C. Juan
- Nanotechnology & Catalysis Research Centre (NanoCat)
- Institute of Postgraduate Studies
- University of Malaya
- 50603 Kuala Lumpur
- Malaysia
| | - W. T. Chong
- Department of Mechanical Engineering
- Faculty of Engineering
- University of Malaya
- 50603 Kuala Lumpur
- Malaysia
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Nordblad M, Pedersen AK, Rancke-Madsen A, Woodley JM. Enzymatic pretreatment of low-grade oils for biodiesel production. Biotechnol Bioeng 2015; 113:754-60. [DOI: 10.1002/bit.25846] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/12/2015] [Accepted: 09/21/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Mathias Nordblad
- Department of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs. Lyngby Denmark
| | - Anders K. Pedersen
- Department of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs. Lyngby Denmark
| | | | - John M. Woodley
- Department of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs. Lyngby Denmark
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11
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Poppe JK, Fernandez-Lafuente R, Rodrigues RC, Ayub MAZ. Enzymatic reactors for biodiesel synthesis: Present status and future prospects. Biotechnol Adv 2015; 33:511-25. [PMID: 25687275 DOI: 10.1016/j.biotechadv.2015.01.011] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/28/2015] [Accepted: 01/29/2015] [Indexed: 12/16/2022]
Abstract
Lipases are being extensively researched for the production of biodiesel as a "silver bullet" in order to avoid the drawbacks of the traditional alkaline transesterification. In this review, we analyzed the main factors involved in the enzymatic synthesis of biodiesel, focusing in the choice of the immobilization protocol, and the parameters involved in the choice and configuration of the reactors. An extensive discussion is presented about the advantages and disadvantages of each type of reactor and their mode of operation. The current scenario of the market for enzymatic biodiesel and some future prospects and necessary developments are also briefly presented.
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Affiliation(s)
- Jakeline Kathiele Poppe
- Biotechnology, Bioprocess, and Biocatalysis Group, Food Science and Technology Institute, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, PO Box 15090, ZC 91501-970 Porto Alegre, RS, Brazil
| | | | - Rafael C Rodrigues
- Biotechnology, Bioprocess, and Biocatalysis Group, Food Science and Technology Institute, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, PO Box 15090, ZC 91501-970 Porto Alegre, RS, Brazil.
| | - Marco Antônio Záchia Ayub
- Biotechnology, Bioprocess, and Biocatalysis Group, Food Science and Technology Institute, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, PO Box 15090, ZC 91501-970 Porto Alegre, RS, Brazil.
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12
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Price J, Hofmann B, Silva VTL, Nordblad M, Woodley JM, Huusom JK. Mechanistic modeling of biodiesel production using a liquid lipase formulation. Biotechnol Prog 2014; 30:1277-90. [DOI: 10.1002/btpr.1985] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 06/26/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Jason Price
- Dept. of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs Lyngby Denmark
| | - Björn Hofmann
- Dept. of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs Lyngby Denmark
| | - Vanessa T. L. Silva
- Dept. of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs Lyngby Denmark
| | - Mathias Nordblad
- Dept. of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs Lyngby Denmark
| | - John M. Woodley
- Dept. of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs Lyngby Denmark
| | - Jakob K. Huusom
- Dept. of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs Lyngby Denmark
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13
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Luna C, Verdugo C, Sancho ED, Luna D, Calero J, Posadillo A, Bautista FM, Romero AA. Production of a biodiesel-like biofuel without glycerol generation, by using Novozym 435, an immobilized Candida antarctica lipase. BIORESOUR BIOPROCESS 2014. [DOI: 10.1186/s40643-014-0011-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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14
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Nordblad M, Silva VTL, Nielsen PM, Woodley JM. Identification of critical parameters in liquid enzyme-catalyzed biodiesel production. Biotechnol Bioeng 2014; 111:2446-53. [DOI: 10.1002/bit.25305] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 05/23/2014] [Accepted: 05/27/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Mathias Nordblad
- Department of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs. Lyngby Denmark
| | - Vanessa T. L. Silva
- Department of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs. Lyngby Denmark
| | | | - John M. Woodley
- Department of Chemical and Biochemical Engineering; Technical University of Denmark; DK-2800 Kgs. Lyngby Denmark
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Lotti M, Pleiss J, Valero F, Ferrer P. Effects of methanol on lipases: molecular, kinetic and process issues in the production of biodiesel. Biotechnol J 2014; 10:22-30. [PMID: 25046365 DOI: 10.1002/biot.201400158] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Revised: 04/05/2014] [Accepted: 06/11/2014] [Indexed: 01/05/2023]
Abstract
The biotechnological production of biodiesel is based on transesterification/esterification reactions between a source of fatty acids and a short-chain alcohol, usually methanol, catalysed by enzymes belonging to the class known as lipases. Several lipases used in industrial processes, although stable in the presence of other organic solvents, are inactivated by methanol at or below the concentration optimal for biodiesel production, making it necessary to use stepwise methanol feeding or pre-treatment of the enzyme. In this review article we focus on what is currently know about methanol inactivation of lipases, a phenomenon which is not common to all lipase enzymes, with the goal of improving the biocatalytic process. We suggest that different mechanisms can lead to inactivation of different lipases, in particular substrate inhibition and protein unfolding. Attempts to improve the performances of methanol sensitive lipases by mutagenesis as well as process engineering approaches are also summarized.
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Affiliation(s)
- Marina Lotti
- Department of Biotechnology and Biosciences, State University of Milano Bicocca, Milano, Italy.
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17
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Influence of feedstock source on the biocatalyst stability and reactor performance in continuous biodiesel production. J IND ENG CHEM 2014. [DOI: 10.1016/j.jiec.2013.06.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Šinkūnienė D, Adlercreutz P. Effects of Regioselectivity and Lipid Class Specificity of Lipases on Transesterification, Exemplified by Biodiesel Production. J AM OIL CHEM SOC 2014; 91:1283-1290. [PMID: 25045169 PMCID: PMC4070466 DOI: 10.1007/s11746-014-2465-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 02/26/2014] [Accepted: 03/25/2014] [Indexed: 12/01/2022]
Abstract
Lipase-catalyzed ethanolysis of triolein was studied as a model for biodiesel production. Four lipases were immobilized on porous polypropylene, and ethanolysis reactions were carried out in methyl t-butyl ether. The reaction products were analyzed using gas chromatography. Three of the four lipases studied were efficient in the conversion of triolein to 2-monoolein, but slow in the final step of producing glycerol. However, Candida antarctica lipase B was slow in the conversion of triolein, but more efficient in the subsequent two steps than the other lipases. The 1,3-selectivity of the lipases was less pronounced for the monooleins than for triolein. Silica gel was investigated as a catalyst for acyl migration, showing an increase in biodiesel yield with three of the lipases, but a reduction in yield when C. antarctica lipase B was used. The highest biodiesel yield (96 %) was obtained with a combination of Rhizopus arrhizus lipase and C. antarctica lipase B.
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Affiliation(s)
- Dovilė Šinkūnienė
- Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
- Present Address: Department of Biochemistry and Molecular Biology, Vilnius University, M. K. Čiurlionio g. 21, 03101 Vilnius, Lithuania
| | - Patrick Adlercreutz
- Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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Brault G, Shareck F, Hurtubise Y, Lépine F, Doucet N. Short-chain flavor ester synthesis in organic media by an E. coli whole-cell biocatalyst expressing a newly characterized heterologous lipase. PLoS One 2014; 9:e91872. [PMID: 24670408 PMCID: PMC3966760 DOI: 10.1371/journal.pone.0091872] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 02/16/2014] [Indexed: 11/18/2022] Open
Abstract
Short-chain aliphatic esters are small volatile molecules that produce fruity and pleasant aromas and flavors. Most of these esters are artificially produced or extracted from natural sources at high cost. It is, however, possible to 'naturally' produce these molecules using biocatalysts such as lipases and esterases. A gene coding for a newly uncovered lipase was isolated from a previous metagenomic study and cloned into E. coli BL21 (DE3) for overexpression using the pET16b plasmid. Using this recombinant strain as a whole-cell biocatalyst, short chain esters were efficiently synthesized by transesterification and esterification reactions in organic media. The recombinant lipase (LipIAF5-2) showed good affinity toward glyceryl trioctanoate and the highest conversion yields were obtained for the transesterification of glyceryl triacetate with methanol. Using a simple cetyl-trimethylammonium bromide pretreatment increased the synthetic activity by a six-fold factor and the whole-cell biocatalyst showed the highest activity at 40°C with a relatively high water content of 10% (w/w). The whole-cell biocatalyst showed excellent tolerance to alcohol and short-chain fatty acid denaturation. Substrate affinity was equally effective with all primary alcohols tested as acyl acceptors, with a slight preference for methanol. The best transesterification conversion of 50 mmol glyceryl triacetate into isoamyl acetate (banana fragrance) provided near 100% yield after 24 hours using 10% biocatalyst loading (w/w) in a fluidized bed reactor, allowing recycling of the biocatalyst up to five times. These results show promising potential for an industrial approach aimed at the biosynthesis of short-chain esters, namely for natural flavor and fragrance production in micro-aqueous media.
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Affiliation(s)
- Guillaume Brault
- INRS-Institut Armand-Frappier, Université du Québec, Laval, Québec, Canada
| | - François Shareck
- INRS-Institut Armand-Frappier, Université du Québec, Laval, Québec, Canada
| | - Yves Hurtubise
- Innu-Science Canada, Inc., Local 119, Trois-Rivières, Québec, Canada
| | - François Lépine
- INRS-Institut Armand-Frappier, Université du Québec, Laval, Québec, Canada
| | - Nicolas Doucet
- INRS-Institut Armand-Frappier, Université du Québec, Laval, Québec, Canada
- PROTEO, the Québec Network for Research on Protein Function, Structure, and Engineering, Québec, Canada
- GRASP, Groupe de Recherche Axé sur la Structure des Protéines, Québec, Canada
- * E-mail:
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