Ispitivanje specifičnosti lipaze iz Candida rugosa u reakciji esterifikacije u organskom rastvaraču
| Autor: | Z Dusan Mijin, Nevena Ognjanovic, Ivana Karalazic, I Dejan Bezbradica, Zorica Knezevic, Slavica Šiler-Marinković |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2006 |
| Předmět: |
0106 biological sciences
esterification specificity 01 natural sciences Catalysis lcsh:Chemistry chemistry.chemical_compound 010608 biotechnology candida rugosa lipase Organic chemistry Lipase Hexanoic acid biology 010405 organic chemistry Substrate (chemistry) General Chemistry Decanoic acid Enzyme assay 0104 chemical sciences Candida rugosa chemistry lcsh:QD1-999 Pentyl propanoate biology.protein |
| Zdroj: | Journal of the Serbian Chemical Society, Vol 71, Iss 1, Pp 31-41 (2006) Journal of the Serbian Chemical Society |
| ISSN: | 1820-7421 0352-5139 |
| Popis: | In this study, the feasibility of the synthesis of various flavor esters catalyzed by a commercial lipase from Candida rugosa was investigated and the process parameters were optimized. Lipase from C. rugosa successfully catalyzed the synthesis of 19 esters. The highest yields, of more than 90 % after 20 h, were observed in the synthesis of short-chain esters, pentyl propanoate, isopentyl butanoate, and butyl butanoate. Increasing the number of carbon atoms of both substrates above 8 caused a significant decrease of the initial reaction rates and the final yields. The enzyme showed surprisingly low affinity towards pentanoic acid and hexanoic acid, compared with the higher homologues, octanoic acid and decanoic acid. In addition to the number of carbon atoms, the structure of the substrates had a significant influence on the enzyme activity. Namely, the activity of the enzyme towards isopropanol was significantly lower compared with n-propanol. Additionally, cis-9-octadecenoic acid was a better substrate than octadecanoic acid, its saturated analogue. Cilj ovog rada je bio ispitivanje mogućnosti sinteze različitih estara pomoću lipaze iz Candida rugosa kao i optimizacija procesnih parametara. Pokazano je da se data lipaza može koristiti kao efikasan biokatalizator za dobijanje devetnaest različitih estara. Najveći prinosi, veći od 90%, dobijeni su u slučaju sinteze nižih estara kao što su pentil-propanoat, 2-metilbutil-butanoat i butil-butanoat. Početna brzina sinteze estara i krajnji prinosi bili su znatno niži sa supstratima koji sadrže više od 8 ugljenikovih atoma. Enzim je pokazao iznenađujuće mali afinitet prema pentanskoj i heksanskoj kiselini, u poređenju sa višim homolozima, oktanskom i dekanskom.Pored broja ugljenikovih atoma, na aktivnost enzima značajno je uticalo prisustvo dvostruke veze u molekulu supstrata i razgranatost supstrata. Naime, lipaza iz C. rugosa ispoljila je mnogo manju aktivnost u reakciji sa izopropanolom nego sa propanolom, dok je pokazala mnogo veći afinitet prema 9-cis-oktadecenskoj kiselini u odnosu na njen zasićeni analog, oktadekansku kiselinu. |
| Databáze: | OpenAIRE |
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