Synthesis of citronellol laurate in organic media catalyzed by immobilized lipases: kinetic studies

Yadav, Ganapati D.; Lathi, Piyush S.

doi:10.1016/j.molcatb.2003.10.004

Cited by 126 publications

(76 citation statements)

References 17 publications

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“…Other advantages include increased solubility of nonpolar substrate, elimination of side reactions, ease of enzyme and product recovery, and increased enzyme thermostability. 11 Various nucleophiles, such as hydroxylamines, 12 oximes 13 and hydrazine, 12 and hydrogen peroxide 14 have been studied for lipasecatalyzed reaction. Reactions of hydroxylamine and hydrazine with octanoic acid and also ethyloctanoate in the presence of lipase have been reported.…”

Section: Introductionmentioning

confidence: 99%

Synergism of microwave irradiation and enzyme catalysis in synthesis of isoniazid

Yadav

Sajgure

2007

J of Chemical Tech & Biotech

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Isoniazid is a useful antitubercular drug widely employed in combination therapy with rifampicin. The synthesis of isoniazid from ethyl isonicotinate and hydrazine hydrate was studied in non-aqueous media via lipase-catalyzed hydrazinolysis under both conventional heating and microwave irradiation by using different supported lipases. Among three different commercial lipases used, namely Novozym 435 (Candida antarctica lipase), Lipozyme RM IM (Rhizomucor miehei lipase) and Lipozyme TL IM (Thermomyces lanuginosus lipase), Novozym 435 was found to be the most effective, with conversion of 54% for equimolar concentrations at 50• C in 4 h. The rate of reaction as well as final conversion increased synergistically under microwave irradiation in comparison with conventional heating, which showed 36.4% conversion, even after 24 h, for the control experiment. Effects of various process parameters such as speed of agitation, catalyst loading, substrate concentration, product concentration and temperature were studied. A kinetic model is also described.

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Section: Introductionmentioning

confidence: 99%

Synergism of microwave irradiation and enzyme catalysis in synthesis of isoniazid

Yadav

Sajgure

2007

J of Chemical Tech & Biotech

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“…Sá et al (2007) também utilizaram a resina Amberlyst 15 para a acetilação de α-metileno-β-hidróxi ésteres e obtiveram conversões de 100% em 30 minutos de reação. No estudo da cinética para a síntese do éster laurato de citronelila via catálise enzimática, na presença do solvente heptano, a melhor conversão obtida foi de 53% em 2 horas de reação, além da baixa conversão e do uso de solvente foi necessária a agitação do sistema reacional Lathi, 2004). Chiaradia et al (2012) também estudaram a síntese de acetato de eugenila, porém catalisada enzimaticamente.…”

Section: Resultsunclassified

Seleção De Catalisadores E Sistema Reacional Para a Síntese De Acetato De Eugenila via Catálise Heterogênea Em Sistema Livre De Solvente

Laroque¹,

Loss²,

Silva³

et al. 2015

Anais Do XX Congresso Brasileiro De Engenharia Química

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RESUMO -Acetato de eugenila é um éster que apresenta propriedades interessantes do ponto de vista industrial, porém, pequena disponibilidade na natureza. O presente trabalho objetivou avaliar diferentes sistemas reacionais e catalisadores na síntese do éster via catálise heterogênea a partir de óleo essencial de cravo-da-índia (85% de eugenol) e anidrido acético, na razão molar 1:3, com 20% (m/m de substratos) dos catalisadores: peneira molecular 4Å, resinas de troca iônica (Amberlyst 15, Amberlyst 15 H + e Amberlyst 36) e resina não iônica (Amberlite XAD-16) em 2 h de reação a 55 °C. Foram testados 3 sistemas reacionais: agitação com ultrassom e shaker e sem agitação. Todos os catalisadores testados foram eficazes para a síntese do éster, com conversões acima de 80%, porém as reações com as resinas de troca iônica apresentaram coloração escura, necessitando de etapa subsequente de purificação. Desta forma, peneira molecular 4Å e resina não iônica Amberlite XAD-16, em sistema sem agitação, foram selecionados como catalisadores e sistema reacional para trabalhos futuros. Além disso, as reações estudadas empregaram condições reacionais simples e uso de tecnologia limpa, com potencial para aplicação em processos industriais. INTRODUÇÃOOs óleos essenciais são líquidos oleosos aromáticos obtidos a partir de material vegetal (flores, brotos, sementes, folhas, galhos, cascas, ervas, madeira, frutas e raízes) (Guenther, 1948). São conhecidos por suas propriedades aromáticas e medicinais, sendo largamente utilizados como conservantes de alimentos, antimicrobianos, analgésicos, sedativos, antiinflamatórios e anestésicos. Dentre os óleos essenciais, o de cravo-da-índia apresenta propriedades biológicas interessantes para aplicação na indústria de alimentos, farmacêutica e de cosméticos. Alguns autores atribuem as atividades benéficas ao seu composto majoritário, o eugenol, caracterizado pela baixa solubilidade e estabilidade (He et al., 2007; Campaniello et al., 2010;Devi et al., 2010). Porém, para contornar esses problemas, é possível a aplicação de metodologias de proteção de grupos, como por exemplo, através da acetilação por esterificação, produzindo assim, o éster acetato de eugenila, composto de pequena disponibilidade na natureza e com diversas propriedades de interesse industrial: atividade Área temática: Engenharia de Reações Químicas e Catálise 1

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“…This can be explained because at this agitation speed the external mass transfer rates between the bulk phase of the reaction mixture and the surface of enzymes decreased. Furthermore, the activity of enzymes at higher speed was also lower due to perturbation of protein structure by the shear effect during hydrolysis process and then, it will inactivate the catalytic power of enzymes [14], [15]. IV.…”

Section: Activity Of Encapsulated Enzymesmentioning

confidence: 99%

Effect of Agitation Speed for Enzymatic Hydrolysis of Tapioca Slurry Using Encapsulated Enzymes in an Enzyme Bioreactor

Rahim¹,

Sulaiman²,

Hamid³

et al. 2015

IJCEA

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Abstract-Agitation speed is an important factor in the industrial application for the mixing efficiency in order to increase productivity. In this study, the effect of agitation speed was investigated in a stirred bioreactor for hydrolysis of tapioca slurry into glucose by using encapsulated enzymes within calcium alginate-clay (alg-clay) beads. The hydrolysis process was tested at various agitation speeds from 40 to 200 rpm. The stability of alg-clay beads was examined in term of morphology of beads, enzyme leaching behavior and enzymes activity. The morphology of the alg-clay beads was investigated by Field Emission Scanning Electron Microscopy (FESEM). It was found that vigorous speed ruptured the beads structure. The result also showed that by increasing the agitation speed, the leakage of enzymes also increased. Therefore, it can be concluded that there was a strong correlation between the speed of agitation and the beads morphology. The optimum agitation speed which gave the highest amount of enzymes activity was 120 rpm.

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Synthesis of citronellol laurate in organic media catalyzed by immobilized lipases: kinetic studies

Cited by 126 publications

References 17 publications

Synergism of microwave irradiation and enzyme catalysis in synthesis of isoniazid

Synergism of microwave irradiation and enzyme catalysis in synthesis of isoniazid

Seleção De Catalisadores E Sistema Reacional Para a Síntese De Acetato De Eugenila via Catálise Heterogênea Em Sistema Livre De Solvente

Effect of Agitation Speed for Enzymatic Hydrolysis of Tapioca Slurry Using Encapsulated Enzymes in an Enzyme Bioreactor

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