In this paper, Lipozyme TLIM-catalyzed synthesis of ethyl cinnamate through esterification of cinnamic acid with ethanol was studied. In order to increase the yield of ethyl cinnamate, several media, including acetone, isooctane, DMSO and solvent-free medium, were investigated in this reaction. The reaction showed a high yield by using isooctane as reaction medium, which was found to be much higher than the yields reported previously. Furthermore, several parameters such as shaking rate, water activity, reaction temperature, substrate molar ratio and enzyme loading had important influences on this reaction. For instance, when temperature increased from 10 to 50 degrees C, the initial reaction rate increased by 18 times and the yield of ethyl cinnamate increased by 6.2 times. Under the optimum conditions, lipase-catalyzed synthesis of ethyl cinnamate gave a maximum yield of 99%, which was of general interest for developing industrial processes for the preparation of ethyl cinnamate.
        
Title: Insight into microwave-assisted lipase catalyzed synthesis of geranyl cinnamate: optimization and kinetic modeling Shinde SD, Yadav GD Ref: Appl Biochem Biotechnol, 175:2035, 2015 : PubMed
Cinnamate esters have gained importance due to their unique antioxidant, flavor, and fragrance properties. Synergism of microwave irradiation and enzyme catalysis was investigated in transesterification of ethyl cinnamate and geraniol. Effects of different operating parameters such as biocatalyst, solvent, and temperature were first studied. An increase in initial rates up to 4.2-fold was observed under microwave irradiation vis-a-vis conventional heating. Further, the Taguchi L16 (4*4) orthogonal array design with four level-four variables and 16 run was employed for the optimization of parameters including enzyme loading, temperature, speed of agitation, and substrate mole ratio. Optimal conditions obtained via the Taguchi approach were as follows: enzyme loading, 60 mg; temperature, 65 degreesC; speed of agitation, 300 rpm; and substrate mole ratio, 1:2. The analysis of initial rate data established the validity of the ternary complex ordered bi-bi mechanism with inhibition by geraniol. The experimental data fitted very well with the model predictions.
The release of polysaccharide from the plant cell wall is a key process to release the stored energy from plant biomass. Within the ruminant digestive system, a host of commensal microorganisms speed the breakdown of plant cell matter releasing fermentable sugars. The presence of phenolic compounds, most notably ferulic acid (FA), esterified within the cell wall is thought to pose a significant impediment to the degradation of the plant cell wall. The structure of a FA esterase from the ruminant bacterium Butyrivibrio proteoclasticus has been determined in two different space groups, in both the apo-form, and the ligand bound form with FA located in the active site. The structure reveals a new lid domain that has no structural homologues in the PDB. The flexibility of the lid domain is evident by the presence of three different conformations adopted by different molecules in the crystals. In the FA-bound structures, these conformations show sequential binding and closing of the lid domain over the substrate. Enzymatic activity assays demonstrate a broad activity against plant-derived hemicellulose, releasing at least four aromatic compounds including FA, coumaric acid, coumarin-3-carboxylic acid, and cinnamic acid. The rumen is a complex ecosystem that efficiently degrades plant biomass and the genome of B. proteoclasticus contains greater than 130 enzymes, which are potentially involved in this process of which Est1E is the first to be well characterized.
https://www.researchsquare.com/article/rs-3196380/latest.pdf
Polyethylene terephthalate (PET) is a commodity polymer known to globally contaminate marine and terrestrial environments. Today, around 80 bacterial and fungal PET-active enzymes (PETases) are known, originating from four bacterial and two fungal phyla. In contrast, no archaeal enzyme has been identified to degrade PET. Here we report on the structural and biochemical characterization of PET46, an archaeal promiscuous feruloyl esterase exhibiting degradation activity on semi-crystalline PET powder comparable to IsPETase and LCC (wildtypes), and higher activity on bis-, and mono-(2-hydroxyethyl) terephthalate (BHET and MHET). The enzyme, found by a sequence-based metagenome search, was derived from a non-cultivated, deep-sea Candidatus Bathyarchaeota archaeon. Biochemical characterization demonstrated that PET46 is a promiscuous, heat-adapted hydrolase. Its crystal structure was solved at a resolution of 1.71 A. It shares the core alpha/beta-hydrolase fold with bacterial PETases, but contains a unique lid common in feruloyl esterases, which is involved in substrate binding. Thus, our study widens the currently known diversity of PET-hydrolyzing enzymes, by demonstrating PET depolymerization by a plant cell wall-degrading esterase.
        
Title: Acaricidal potential of active components derived from Alpinia galanga rhizome oils and their derivatives against Haemaphysalis longicornis (Acari: Ixodidae) Kang MS, Park JH, Lee HS Ref: Exp Appl Acarol, :, 2022 : PubMed
Acaricidal activities and acetylcholinesterase (AChE) inhibitory activities were evaluated of active constituents of the essential oil extracted from Alpinia galanga rhizomes cultivated from India and their derivatives against Haemaphysalis longicornis nymphs. In addition, the effect was investigated of active components of A. galanga oil on egg laying of adult females of H. longicornis and egg hatchability. Of the volatile components identified in A. galanga oil, ethyl cinnamate, ethyl methoxycinnamate, and methyl cinnamate at 0.32 mg/cm(2) resulted in 100% mortality, respectively, indicating that the acaricidal activity of the A. galanga oil against H. longicornis nymphs could be attributed to these compounds. To evaluate the structure-activity relationship between cinnamate derivatives and their acaricidal activities, allyl cinnamate, benzyl cinnamate, isopropyl cinnamate, isobutyl cinnamate, and isoamyl cinnamate were selected. Among cinnamate derivatives tested, allyl cinnamate exhibited the most potent toxicity (LC(50) = 0.055 mg/cm(2)) against H. longicornis nymphs. The allyl cinnamate was also tested for AChE activity in vivo in H. longicornis nymphs and was found to affect the AChE activity. Allyl cinnamate at 10-50 mg/mL inhibited egg laying of adult females of H. longicornis by 10-43%. Egg hatching was suppressed completely by treatment with allyl cinnamate at 50 mg/mL, whereas allyl cinnamate was minimally toxic against non-target earthworms, Eisenia fetida. These results suggest that allyl cinnamate can be used as an active ingredient for the development of eco-friendly tick acaricides against H. longicornis, a vector for Sever fever with thrombocytopenia syndrome (SFTS) virus.
        
Title: High-yield synthesis of bioactive ethyl cinnamate by enzymatic esterification of cinnamic acid Wang Y, Zhang DH, Zhang JY, Chen N, Zhi GY Ref: Food Chem, 190:629, 2016 : PubMed
In this paper, Lipozyme TLIM-catalyzed synthesis of ethyl cinnamate through esterification of cinnamic acid with ethanol was studied. In order to increase the yield of ethyl cinnamate, several media, including acetone, isooctane, DMSO and solvent-free medium, were investigated in this reaction. The reaction showed a high yield by using isooctane as reaction medium, which was found to be much higher than the yields reported previously. Furthermore, several parameters such as shaking rate, water activity, reaction temperature, substrate molar ratio and enzyme loading had important influences on this reaction. For instance, when temperature increased from 10 to 50 degrees C, the initial reaction rate increased by 18 times and the yield of ethyl cinnamate increased by 6.2 times. Under the optimum conditions, lipase-catalyzed synthesis of ethyl cinnamate gave a maximum yield of 99%, which was of general interest for developing industrial processes for the preparation of ethyl cinnamate.
        
Title: Insight into microwave-assisted lipase catalyzed synthesis of geranyl cinnamate: optimization and kinetic modeling Shinde SD, Yadav GD Ref: Appl Biochem Biotechnol, 175:2035, 2015 : PubMed
Cinnamate esters have gained importance due to their unique antioxidant, flavor, and fragrance properties. Synergism of microwave irradiation and enzyme catalysis was investigated in transesterification of ethyl cinnamate and geraniol. Effects of different operating parameters such as biocatalyst, solvent, and temperature were first studied. An increase in initial rates up to 4.2-fold was observed under microwave irradiation vis-a-vis conventional heating. Further, the Taguchi L16 (4*4) orthogonal array design with four level-four variables and 16 run was employed for the optimization of parameters including enzyme loading, temperature, speed of agitation, and substrate mole ratio. Optimal conditions obtained via the Taguchi approach were as follows: enzyme loading, 60 mg; temperature, 65 degreesC; speed of agitation, 300 rpm; and substrate mole ratio, 1:2. The analysis of initial rate data established the validity of the ternary complex ordered bi-bi mechanism with inhibition by geraniol. The experimental data fitted very well with the model predictions.
The release of polysaccharide from the plant cell wall is a key process to release the stored energy from plant biomass. Within the ruminant digestive system, a host of commensal microorganisms speed the breakdown of plant cell matter releasing fermentable sugars. The presence of phenolic compounds, most notably ferulic acid (FA), esterified within the cell wall is thought to pose a significant impediment to the degradation of the plant cell wall. The structure of a FA esterase from the ruminant bacterium Butyrivibrio proteoclasticus has been determined in two different space groups, in both the apo-form, and the ligand bound form with FA located in the active site. The structure reveals a new lid domain that has no structural homologues in the PDB. The flexibility of the lid domain is evident by the presence of three different conformations adopted by different molecules in the crystals. In the FA-bound structures, these conformations show sequential binding and closing of the lid domain over the substrate. Enzymatic activity assays demonstrate a broad activity against plant-derived hemicellulose, releasing at least four aromatic compounds including FA, coumaric acid, coumarin-3-carboxylic acid, and cinnamic acid. The rumen is a complex ecosystem that efficiently degrades plant biomass and the genome of B. proteoclasticus contains greater than 130 enzymes, which are potentially involved in this process of which Est1E is the first to be well characterized.
        
Title: Radical scavenging activity of lipophilized products from lipase-catalyzed transesterification of triolein with cinnamic and ferulic acids Choo WS, Birch EJ Ref: Lipids, 44:145, 2009 : PubMed
Lipase-catalyzed transesterification of triolein with cinnamic and ferulic acids using an immobilized lipase from Candida antarctica (E.C. 3.1.1.3) was conducted to evaluate the antioxidant activity of the lipophilized products as model systems for enhanced protection of unsaturated oil. The lipophilized products were identified using ESI-MS. Free radical scavenging activity was determined using the DPPH radical method. The polarity of the solvents proved important in determining the radical scavenging activity of the substrates. Ferulic acid showed much higher radical scavenging activity than cinnamic acid, which has limited activity. The esterification of cinnamic acid and ferulic acid with triolein resulted in significant increase and decrease in the radical scavenging activity, respectively. These opposite effects were due to the effect of addition of electron-donating alkyl groups on the predominant mechanism of reaction (hydrogen atom transfer or electron transfer) of a species with DPPH. The effect of esterification of cinnamic acid was confirmed using ethyl cinnamate which greatly enhances the radical scavenging activity. Although, compared to the lipophilized cinnamic acid product, the activity was lower. The radical scavenging activity of the main component isolated from lipophilized cinnamic acid product using solid phase extraction, monocinnamoyl dioleoyl glycerol, was as good as the unseparated mixture of lipophilized product. Based on the ratio of a substrate to DPPH concentration, lipophilized ferulic acid was a much more efficient radical scavenger than lipophilized cinnamic acid.