Xi:Irritant;
106-29-6Relevant articles and documents
Covalently immobilized lipase catalyzing high-yielding optimized geranyl butyrate synthesis in a batch and fluidized bed reactor
Damnjanovic, Jasmina J.,Zuza, Milena G.,Savanovic, Jova K.,Bezbradica, Dejan I.,Mijin, Dusan Z.,Boskovic-Vragolovic, Nevenka,Knezevic-Jugovic, Zorica D.
, p. 50 - 59 (2012)
Three commercially available polymers (Sepabeads EC-EP, Sepabeads EC-HA and Purolite A-109) were tested for potential application as supports for covalent immobilization of lipase from Candida rugosa by analyzing some critical properties of immobilized enzymes such as enzyme loading, activity and activity immobilization yield. Among them, lipase covalently immobilized on Sepabeads EC-EP via epoxy groups appeared to show the best performance in a standard hydrolytic reaction. Therefore, it was selected and assayed in the esterification of butyric acid and geraniol to produce geranyl butyrate, first in a batch system followed by continuous geranyl butyrate synthesis in a fluidized bed reactor, as one being potentially applicable for large-scale production. Based on statistical analysis, optimal conditions for the production of geranyl butyrate by selected, immobilized lipase in the batch system are recommended as: temperature at 25-30°C, water concentration at 3.6% (v/v) and acid/alcohol molar ratio at 2.5. A set of optimal conditions for the ester synthesis in a fluidized bed reactor system has also been determined, specifically, flow rate at 10 mL min-1, temperature at 35°C, water concentration at 2% (v/v), substrate concentration at 0.1 M and acid/alcohol ratio at 2.0. Implementation of the optimized parameters in a batch system and in a fluidized bed reactor enabled production of target ester with high molar conversion, at > 99.9% for 48 h in the batch process, and 78.9% for 10 h in fluidized bed reactor. Although when assayed at their optimal conditions, lower molar conversion was achieved in the fluidized bed reactor system compared to the batch system, the volumetric productivity in fluidized bed reactor was more than five fold higher than that obtained in the batch system.
Efficient Enzymatic Preparation of Flavor Esters in Water
Perdomo, Igor Chiarelli,Gianolio, Stefania,Pinto, Andrea,Romano, Diego,Contente, Martina Letizia,Paradisi, Francesca,Molinari, Francesco
, p. 6517 - 6522 (2019/06/20)
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.
The potential use of geraniol esters from citronella oil as anticancer agent
Widiyarti, Galuh,Megawati, Megawati,Hanafi, Muhammad
, p. 987 - 996 (2019/07/12)
Geraniol which is mainly contained in citronella oil is one of the Indonesian natural products with anticancer potential. In this study, synthesis of geranyl butyrate, geranyl caproate, and geranyl caprylate from geraniol was conducted using sodium hydroxide as a catalyst.The aim was to enhance the anticancer activity of geraniol as a starting material. In order to achieve this, its esters were identified through the use of Gas Chromatography-Mass Spectroscopy (GCMS), Fourier Transform Infra Red (FTIR), Thin Layer Chromatography (TLC), and Proton Nuclear Magnetic Resonance (1H-NMR).They were analyzed for their potential as anticancer agents through Brine Shrimp Lethality Test (BSLT) against Artemia salina Leach, Mosmann method against murine leukemia (P388) cells and normal (Vero) cells. It was found that geraniol esters have the potential to be anticancer compounds. This was indicated by LC50 values of 0.96-1.46 μg/ml against A. salina L, IC50 values of 22.34-32.29 μg/ml against P388 cells, and very less cytotoxic effect on Vero cells with IC50 values of 116.08-172.93 μg/ml. Therefore, there is an expectation that acyclic ester compounds should be used in treating cancer.
A clean enzymatic process for producing flavour esters by direct esterification in switchable ionic liquid/solid phases
Lozano, Pedro,Bernal, Juana M.,Navarro, Alicia
, p. 3026 - 3033 (2013/01/15)
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.
Rapeseed lipase catalyzed synthesis of butyl butyrate for flavour and nutraceutical applications in organic media
Liaquat, Muhammad
experimental part, p. 6 - 13 (2012/06/18)
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.
Catalytic generation of activated carboxylates from enals: A product-determining role for the base
Sohn, Stephanie S.,Bode, Jeffrey W.
, p. 3873 - 3876 (2007/10/03)
(Chemical Equation Presented) N-Heterocycle carbenes generated in situ from imidazolium or triazolium salts and bases react with enals, leading to the catalytic generation of homoenolates. The fate of these intermediates is determined by the catalytic base: strong bases such as tBuOK lead to carbon-carbon bond formation, while weaker bases allow protonation of the homoenolate and subsequent generation of activated carboxylates. This discovery, along with the design of a new triazolium precatalyst, enables the catalytic, atom-economical redox esterification of enals.
Identification of presumed pheromone blend from Australasian predaceous bug, Oechalia schellenbergii (Heteroptera: Pentatomidae)
Aldrich, Jeffrey R.,Oliver, James E.,Waite, Geoff K.,Moore, Chris,Waters, Rolland M.
, p. 729 - 738 (2007/10/03)
Oechalia schellenbergii is one of the most common predatory insects in Australia and the islands of the South Pacific. Adult males of this predaceous "true bug" collected during March near Gatton, Queensland, Australia, had a pair of enlarged exocrine glands opening underneath their wings that presumably produce an artractant pheromone. The two major components of the secretion are 3-methylenehexyl acetate and 9-hydroxygeranyl diacetate [2,6-dimethyl-2(E),6(E)-octadien-1,8-diol diacetate].
STEREOSELECTIVE LIPASE-CATALYSED ACYLATION OF TERPENIC ALLYLIC ALCOHOLS BY FATTY ACID ANHYDRIDES
Foumeron, Jean-Dominique,Chiche, Melissa,Pieroni, Gerard
, p. 4875 - 4878 (2007/10/02)
Lipase from pancreatic powder preferentially catalyses the acylation of the E isomer of terpenic allylic alcohols using fatty acid anhydrides as the acylating agent.The course of the reaction can be described by a first-order equation.
Synthesis of Fatty Acid Ester by Corynebacterium sp. S-401
Seo, Chull Won,Yamada, Yasuhiro,Okada, Hirosuke
, p. 405 - 410 (2007/10/02)
Resting cells and acetone-dried cells of Corynebacterium sp.S-401 catalyzed the fatty acid ester synthesis of various alcohols and fatty acids.These reactions were carried out in phosphate buffer and/or organic solvents.In some cases synthetic reactions of esters in nonpolar solvents, such as n-hexane and benzene, gave better results compared with those obtained in phosphate buffer.
