- Lipase-catalyzed synthesis of isoamyl butyrate: Optimization by response surface methodology
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Immobilized lipase from Mucor miehei (Lipozyme IM-20) was employed in the esterification of butyric acid and isoamyl alcohol to synthesize isoamyl butyrate in n-hexane. Response surface methodology based on five-level, five-variable central composite rotatable design was used to evaluate the effects of important variables - enzyme/substrate (E/S) ratio (5-25 g/mol), acid concentration (0.2-1.0 M), alcohol concentration (0.25-1.25 M), incubation period (12-60 h), and temperature (30-50 °C) - on esterification yield of isoamyl butyrate. In the range of parameters studied, the extent of esterification decreased with temperature, lower E/S ratios, and incubation periods. Excess acid and alcohol concentrations (i.e., acid/alcohol>1.4 or alcohol/acid>1.4) were found to decrease yield probably owing to inhibition of the enzyme by acid or alcohol, the former being more severe. The optimal conditions achieved are as follows: E/S ratio, 17 g/mol; acid concentration, 1.0 M; incubation period, 60 h; alcohol concentration, 1.25 M; and temperature, 30 °C. With these conditions, the predicted value was 1.0 M ester, and the actual experimental value was 0.98 M.
- Krishna, S. Hari,Manohar,Divakar,Karanth
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- Enzymatic synthesis optimization of isoamyl butyrate
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Lipozyme TL IM was used to catalyse the esterification of isoamyl alcohol and butyric acid. A fractional factorial design was employed to evaluate the effects of temperature (30, 40, 50 °C), alcohol:acid molar ratio (1:1, 2:1, 3:1), enzyme concentration (0.003, 0.0115, 0.020 g mL-1), butyric acid concentration (0.1, 0.3, 0.5 mol L-1) and shaking rate (50, 115, 180 rpm) on the ester yield. With these results, the levels were redefined to a 23 factorial design. The maximum yield of ester was obtained at 30 °C, 180 rpm, alcohol:acid molar ratio of 1:1, enzyme concentration of 0.021 g mL-1 and butyric acid concentration of 0.5 mol L-1. Under the optimal conditions, 92% esterification was attained with an ester concentration of 0.9 mol L-1. Isoamyl alcohol from fusel oil was used under the same conditions and resulted in 93% esterification and an ester concentration of 1.0 mol L-1.
- Anschau, Andreia,Aragao, Vitor C.,Porciuncula, Barbara D.A.,Kalil, Susana J.,Burkert, Carlos A.V.,Burkert, Janaina F.M.
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- Efficient Enzymatic Preparation of Flavor Esters in Water
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A straightforward biocatalytic method for the enzymatic preparation of different flavor esters starting from primary alcohols (e.g., isoamyl, n-hexyl, geranyl, cinnamyl, 2-phenethyl, and benzyl alcohols) and naturally available ethyl esters (e.g., formate, acetate, propionate, and butyrate) was developed. The biotransformations are catalyzed by an acyltransferase from Mycobacterium smegmatis (MsAcT) and proceeded with excellent yields (80-97%) and short reaction times (30-120 min), even when high substrate concentrations (up to 0.5 M) were used. This enzymatic strategy represents an efficient alternative to the application of lipases in organic solvents and a significant improvement compared with already known methods in terms of reduced use of organic solvents, paving the way to sustainable and efficient preparation of natural flavoring agents.
- Perdomo, Igor Chiarelli,Gianolio, Stefania,Pinto, Andrea,Romano, Diego,Contente, Martina Letizia,Paradisi, Francesca,Molinari, Francesco
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p. 6517 - 6522
(2019/06/20)
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- Synthesis of butyrate using a heterogeneous catalyst based on polyvinylpolypyrrolidone
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A heterogeneous polyvinylpolypyrrolidone supported Br?nsted acidic catalyst ([PVPP-BS]HSO4) was used to synthesize butyrate in this paper. The prepared catalysts were characterized by FT-IR, TG, and FESEM and their catalytic activity in butyric acid esterification with benzyl alcohol was investigated. The influencing factors such as the amount of catalyst, reaction temperature, and reaction time were carefully studied. Under the optimized condition with the butyric acid to benzyl alcohol mole ratio of 1 : 1.2 and the reaction temperature of 130°C, the yield of benzyl butyrate reached 96.8 % within 4 h in the presence of 8 mass % of catalyst. Moreover, the catalyst could be reused six times without noticeable drop in activity. This catalyst was also used to synthesize other kinds of butyrates achieving the butyrate yield above 90 %.
- Wang, Song,Chang, Qian-Qian,Shawgi, Nazar,Li, San-Xi,Zhang, Lin-Nan
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p. 538 - 544
(2016/03/05)
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- The combine use of ultrasound and lipase immobilized on co-polymer matrix for efficient biocatalytic application studies
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In this work, we have investigated the combine use of ultrasound and lipase (Pseudomonas cepacia: PCL) immobilized on co-polymer of polyvinyl alcohol (PVA) and chitosan (CHI) for biocatalytic applications. Initially, we have screened different free and immobilized biocatalysts to find-out the robust biocatalyst. The immobilized biocatalyst PVA:CHI:PCL (5:5:2.5) worked as a robust biocatalyst to provide superior conversion (99%) for the synthesis of model ultrasound assisted reaction. Subsequently, various reaction parameters were optimized in details to obtain the higher yield. Besides this, developed biocatalytic protocol was used to synthesize various industrially important butyrate compounds which provided excellent conversion of 99% under ultrasonic conditions. The developed biocatalyst showed excellent recyclability upto studied five cycles under ultrasonic condition. The immobilized PVA:CHI:PCL biocatalyst displayed 2.4 folds higher activity as compared to free lipases in ultrasonic condition. Moreover, PVA:CHI:PCL biocatalyst in ultrasound media showed 4.5 folds higher activity as compared to free lipases in conventional media. The energy assessment was performed which demonstrated feasibility of combine use of immobilization and ultrasonication to carry out efficient biocatalytic process.
- Badgujar, Kirtikumar Chandulal,Bhanage, Bhalchandra Mahadeo
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p. 255 - 264
(2015/10/28)
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- Solvent stability study with thermodynamic analysis and superior biocatalytic activity of Burkholderia cepacia lipase immobilized on biocompatible hybrid matrix of poly(vinyl alcohol) and hypromellose
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In the present study, we have synthesized a biocompatible hybrid carrier of hypromellose (HY) and poly(vinyl alcohol) (PVA) for immobilization of Burkholderia cepacia lipase (BCL). The immobilized biocatalyst HY:-PVA:BCL was subjected to determination of half-life time (τ) and deactivation rate constant (KD) in various organic solvents. Biocatalyst showed higher τ-value in a nonpolar solvent like cyclohexane (822 h) as compared to that of a polar solvent such as acetone (347 h), which signifies better compatibility of biocatalyst in the nonpolar solvents. Furthermore, the KD-value was found to be less in cyclohexane (0.843 × 10-3) as compared to acetone (1.997 × 10-3), indicating better stability in the nonpolar solvents. Immobilized-BCL (35 mg) was sufficient to achieve 99% conversion of phenethyl butyrate (natural constituent of essential oils and has wide industrial applications) using phenethyl alcohol (2 mmol) and vinyl butyrate (6 mmol) at 44 °C in 3 h. The activation energy (Ea) was found to be lower for immobilized-BCL than crude-BCL, indicating better catalytic e fficiency of immobilized lipase BCL. The immobilized-BCL reported 6-fold superior biocatalytic activity and 8 times recyclability as compared to crude-BCL. Improved catalytic activity of immobilized enzyme in nonpolar media was also supported by thermodynamic activation parameters such as enthalpy (ΔH?), entropy (ΔS?) and Gibb 's free energy (ΔG?) study, which showed that phenethyl butyrate synthesis catalyzed by immobilized-BCL was feasible as compared to crude-BCL. The present work explains a thermodynamic investigation and superior biocatalytic activity for phenethyl butyrate synthesis using biocompatible immobilized HY:PVA:BCL in nonaqueous media for the first time. (Graph Presented).
- Badgujar, Kirtikumar C.,Bhanage, Bhalchandra M.
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p. 14808 - 14819
(2015/02/19)
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- A clean enzymatic process for producing flavour esters by direct esterification in switchable ionic liquid/solid phases
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A clean biocatalytic approach for producing flavour esters using switchable ionic liquid/solid phases as reaction/separation media has been developed. The phase behaviour of different IL/flavour acetyl ester (geranyl acetate, citronellyl acetate, neryl acetate and isoamyl acetate) mixtures was studied at several concentrations, resulting for all cases in fully homogeneous liquid media at 50 °C, and solid systems at room temperature. By using an iterative centrifugation protocol on the solid IL/flavour ester mixtures at controlled temperatures, the solid IL phase and the liquid flavour ester phase can be easily separated. The excellent suitability of an immobilized Candida antarctica lipase B (Novozym 435) catalyst in the esterification reaction between an aliphatic carboxylic acid (acetic, propionic, butyric or valeric) and a flavour alcohol (isoamyl alcohol, nerol, citronellol or geraniol) in N,N′,N′′,N′′′-hexadecyltrimethyl-ammonium bis(trifluoromethylsulfonyl)imide ([C16tma][NTf2])IL has been demonstrated, the product yield being improved up to 100% under appropriate reaction conditions (enzyme amount, dehydrating molecular sieves, etc.) at 50 °C. The enzymatic synthesis of sixteen different flavour esters was carried out in [C16tma][NTf2] by means of this approach, providing products of up to 0.757 g mL-1 concentration after IL separation. The residual activity of the enzyme/IL system during seven consecutive operation cycles was shown to be practically unchanged after reuse.
- Lozano, Pedro,Bernal, Juana M.,Navarro, Alicia
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p. 3026 - 3033
(2013/01/15)
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- Rapeseed lipase catalyzed synthesis of butyl butyrate for flavour and nutraceutical applications in organic media
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Butyl butyrate, a short chain ester with fine fruity pineapple odour, is a significant flavour compound. Recent investigations show that butyrate esters also have anticancer activity. Factors influencing the synthesis of butyl butyrate by organic phase biocatalysis were investigated. Maximum ester yield of 89% was obtained when 0.25 M butanol and butyric acid were reacted at 25 °C for 48 h in the presence of 250 mg rape seed lipase acetone powder in hexane. Addition of water did not affect synthesis, while a water activity of 0.45 was found optimum. Of 15 different alcohols evaluated, isoamyl and (Z)-3- hexen-1-ol were esterified most effectively with molar conversion yields of 92.2 and 80.2%. Short chain primary alcohols such as methanol and medium-long chain alcohols, such as heptanol and octanol were esterified more slowly. The results show that rape seed lipase is versatile catalyst for ester synthesis with temperature stability range 5-50 °C.
- Liaquat, Muhammad
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experimental part
p. 6 - 13
(2012/06/18)
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- Characterization of aroma compounds of Chinese "Wuliangye" and "Jiannanchun" liquors by aroma extract dilution analysis
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Aroma compounds in Chinese "Wuliangye" liquor were identified by gas chromatography-olfactometry (GC-O) after fractionation. A total of 132 odorants were detected by GC-O in Wuliangye liquor on DB-wax and DB-5 columns. Of these, 126 aromas were identified by GC-mass spectrometry (MS). Aroma extract dilution analysis (AEDA) was further employed to identify the most important aroma compounds in "Wuliangye" and "Jiannanchun" liquors. The results showed that esters could be the most important class, especially ethyl esters. Various alcohols, aldehydes, acetals, alkylpyrazines, furan derivatives, lactones, and sulfur-containing and phenolic compounds were also found to be important. On the basis of flavor dilution (FD) values, the most important aroma compounds in Wuliangye and Jiannanchun liquors could be ethyl butanoate, ethyl pentanoate, ethyl hexanoate, ethyl octanoate, butyl hexanoate, ethyl 3-methylbutanoate, hexanoic acid, and 1,1-diethoxy-3-methylbutane (FD ≥ 1024). These compounds contributed to fruity, floral, and apple- and pineapple-like aromas with the exception of hexanoic acid, which imparts a sweaty note. Several pyrazines, including 2,5-dimethyl-3-ethylpyrazine, 2-ethyl-6-methylpyrazine, 2,6-dimethylpyrazine, 2,3,5-tri-methylpyrazine, and 3,5-dimethyl-2-pentylpyrazine, were identified in these two liquors. Although further quantitative analysis is required, it seems that most of these pyrazine compounds had higher FD values in Wuliangye than in Jiannanchun liquor, thus imparting stronger nutty, baked, and roasted notes in Wuliangye liquor.
- Fan, Wenlai,Qian, Michael C.
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p. 2695 - 2704
(2007/10/03)
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- Preparation of salicylic acid resin supported FeCl3 lewis acid catalyst and its application in organic synthesis
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The catalytic effects of salicylic acid resin supported FeCl3 catalyst on the esterification of alcohol and carboxylic acid and on the acetalization (ketal formation) of aldehyde (ketone) and alcohol have been investigated.This catalyst is convenient to use, noncorrosive, easy to be separated from reactants and can be repeatedly used.
- Huirong, Yang,Yingde, Li Bina Cui
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p. 1233 - 1238
(2007/10/03)
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- A study on synthesis of esters by superacid resin catalysts
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Superacid resin as catalyst, instead of the strong acid cation exchange resin and sulfuric acid was used to synthesis n-butyl lactate. Some factors affection reaction, such as time, moles ratio of reactants and catalyst amount were studied. Results made known that time was shorten very much. Under our optimum conditions the ester yield was over 99.5%. In the other hand, superacid resin as catalyst was used to synthesis other esters, had result of raise ester yield and shorten the time of esterification.
- Yang,Li,Fang
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p. 3269 - 3275
(2007/10/02)
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- Schiff base reaction products of aldehydes and alkyl anthranilates and organoleptic uses thereof
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Described are schiff base reaction products of alkyl anthranilates having the structure: STR1 wherein R3 represents methyl or ethyl and aldehydes of the generic structure: STR2 wherein R represents unsaturated hydrocarbyl and alkoxy hydrocarbyl moieties or mixtures of aldehydes having the structures: STR3 wherein R1 and R2 are different alkoxy hydrocarbyl moieties and hydrocarbyl moieties including the aldehydes: (a) bergamal having the structure: STR4 (b) floralozone having the structure: STR5 (c) pino acetaldehyde having the structure: STR6 (d) pino isobutyraldehyde having the structure: STR7 (e) melonal having the structure: STR8 and (f) canthoxal having the structure: STR9 and organoleptic uses thereof in augmenting or enhancing the aroma or taste of consumable materials including perfume compositions, colognes, perfumed articles, foodstuffs, chewing gums and beverages.
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- Ether carbinols and process for preparing same
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Described are ether carbinols defined according to the generic structure: STR1 wherein X1 represents a moiety selected from the group consisting of: STR2 and wherein Y1 represents C4 or C5 alkylene or C4 or C5 alkenylene or C4 or C5 alkynylene; processes for preparing such ether carbinols by means of first reacting allyl ethers with a mixture of carbon monoxide and hydrogen by means of an oxoreaction to produce ether carboxaldehydes and then reducing the thus formed ether carboxaldehydes to ether carbinols; or reacting camphene with appropriate diols; as well as methods for augmenting or enhancing the aroma or taste of consumable materials including perfumes, colognes and perfumed articles; foodstuffs, chewing gums, chewing tobaccos, medicinal products and toothpastes; and smoking tobaccos and smoking tobacco articles by adding thereto an aroma or taste augmenting or enhancing quantity of the thus produced ether carbinols. Also described are two ether carboxaldehydes having one of the structures: STR3 processes for preparing such ether carboxaldehydes by means of reacting out an appropriate allyl ether with a mixture of carbon monoxide and hydrogen by means of an oxo-reaction as well as methods for augmenting or enhancing the aroma or taste of consumable materials including perfumes, colognes and perfumed articles; foodstuffs, chewing gums, chewing tobaccos, medicinal products and toothpastes; smoking tobaccos and smoking tobacco articles by adding thereto an aroma or taste augmenting or enhancing quantity of the thus produced ether carboxaldehydes.
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- Ether carboxaldehydes
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Described are ether carboxaldehydes defined according to the generic structure: STR1 wherein X represents aryl, alkaryl, hydroxyalkyl, alkenyl, cycloalkenyl, lower alkyl or bicycloalkyl; wherein Y represents C1 -C3 lower alkylene; wherein Z completes an alkyl substituted C6 cycloalkyl ring or represents no moiety; wherein R represents hydrogen or methyl; wherein m represents 0 or 1; wherein n represents 0 or 1; wherein p represents 0 or 1 and wherein q represents 0 or 1 with the provisos that when m is 1, Z completes the alkyl substituted or unsubstituted C6 cycloalkyl ring; that p is 1 when q is 0; and that when p is 0, q is 1, processes for producing same by reacting allyl ethers defined according to the structure: STR2 wherein x, y, z, m, n and r are as defined above with a mixture of carbon monoxide and hydrogen by means of an oxo reaction products produced according to said oxo reaction which are mixtures which contain the above-mentioned ether carboxaldehydes as well as methods for augmenting or enhancing the aroma or taste of consumable materials, including perfumes, colognes and perfumed articles; foodstuffs, chewing gums, chewing tobaccos, medicinal products and toothpastes; and smoking tobaccos and smoking tobacco articles by adding thereto aroma or taste augmenting or enhancing quantities of the thus produced ether carboxaldehydes or ether carboxaldehyde-containing mixtures. Also described are perfume compositions, colognes, perfumed articles (including solid or liquid anionic, cationic, nonionic or zwitterionic detergents, fabric softener compositions, drier-added fabric softener articles, hair preparations, deodorant compositions, bleaching compositions and perfumed polymers), foodstuffs, chewing gums, toothpastes, medicinal products, chewing tobaccos, smoking tobaccos and smoking tobacco articles containing the products thus produced.
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- Alkyl esters of 1-alkanoyl cycloalkanols and organoleptic uses thereof
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Described is a process for preparing several substituted or unsubstituted cycloalkyl acyl alkanoates defined according to the generic structure: STR1 wherein R1 and R2 taken together complete a cycloalkyl moiety or methyl, dimethyl or trimethyl substituted cycloalkyl moiety containing five or six carbon atoms in the ring and wherein R3 is C1 -C3 lower alkyl and R4 is methyl or hydrogen by reacting a compound having the generic structure: STR2 in an aqueous silver-ion containing solution having a weakly acidic pH at elevated temperatures. The compounds so produced are useful for their organoleptic properties in consumable materials, such as foodstuffs, foodstuff flavorants, chewing gums, chewing gum flavorants, toothpastes, toothpaste flavorants, medicinal products, medicinal product flavorants, chewing tobaccos, chewing tobacco flavorants, smoking tobaccos, smoking tobacco flavorants, perfume compositions, perfumed articles, such as cationic, anionic, nonionic and zwitterionic detergents, fabric softener compositions, drier-added fabric softener articles, textile sizing agents and optical brighteners for textiles as well as colognes.
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