Lipases are hydrolytic enzymes that catalyze hydrolysis reactions of triacylglycerols in the
presence of water and esterification and transesterification reactions in the absence of water,
having great prominence and importance for applications in the food sector. This work aimed
to select carbon and nitrogen sources for the submerged cultivation of the yeast Candida
viwanathii for the production of lipase, to optimize the nutritional conditions of the culture
medium by the experimental DCCR planning, to apply the optimized conditions in STR
bioreactor and to immobilize the enzyme in magnetic chitosan nanoparticles functionalized
with different activators (glutaraldehyde, epichlorohydrin and ionic liquid) to test the viability
in the production of isoamyl esters with different fatty acids. Under the conditions tested, the
yeast extract obtained the best results, with a production of 7,70 U.mL-1
and as a non-lipid
carbon source, sorbitol stood out with an enzymatic production of 13,66 U.mL-1
. The vegetable
oil selected as an inducing carbon source was soybean oil (12,69 U.mL-1
) in the presence of
sorbitol and yeast extract. After the DCCR, the nutritional parameters sorbitol, yeast extract and
soybean oil obtained the best condition, for the conditions tested, with the use of 7,5 g.L-1
, 10
g.L-1
and 23,4 g.L-1
, respectively , achieving a production of 13,56 U.mL-1
. The best condition
in the bioreactor showed a production similar to that observed after the experimental planning
(13,75 U.mL-1
). Immobilizations performed with different activators reached yields of 96,56%,
93,19%, and 83,5% for nanoparticles activated with epichlorohydrin, glutaraldehyde and ionic
liquid respectively. The highest esterification yields after 24 h of reaction, when octane was
used as solvent, were 12,29% for lauric acid using enzyme immobilized with ionic liquid,
14,5% for myristic acid using enzyme immobilized with glutaraldehyde, 6,65% and 6,61% for
palmitic acid using enzyme immobilized with glutaraldehyde and ionic liquid, and 12,75% for
stearic acid using enzyme immobilized with ionic liquid. With the use of dimethyl sulfoxide as
a solvent, the esterification yields after 24 h were 40% for lauric acid using enzyme immobilized
with glutaraldehyde, 50,53% for myristic acid using enzyme immobilized with ionic liquid,
66,25% for palmitic acid using enzyme immobilized with glutaraldehyde and 68,35% for stearic
acid using enzyme immobilized with glutaraldehyde. Thus, crop optimization to increase
enzyme production was shown to be efficient using a low-cost vegetable oil. In addition, the
immobilization of lipase in magnetic chitosan nanoparticles showed potential for applications
in the synthesis of esters using long-chain fatty acids as substrates. Finally, lipase immobilized
on magnetic chitosan nanoparticles functionalized with glutaraldehyde, epichlorohydrin and
ionic liquid have shown to be promising biocatalysts with high potential for use in the food
industry.
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