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Biosynthesis of Oleyl Oleate Wax Ester by Non-commercial Lipase
Danielle Branta Lopes,Marta Cristina Teixeira Duarte,Gabriela Alves Macedo 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.5
Oleyl oleate can be considered a synthetic analogue of jojoba oil. This one has been the main natural source of wax esters for commercial applications since the global ban on whale hunting. Lipase catalyzed production of this ester was carried out using oleic acid and oleyl alcohol in a solvent-free system. Lipase from Rhizopus sp. CBMAI 1127 was used as the biocatalyst and commercial enzyme Lipozyme TL IM^® was used to compare results. The acid/alcohol molar ratio showed significant effects for both lipases and the amount of enzyme had a significant effect just for Lipozyme TL IM^®. The rate of the esterification reaction using lipase from Rhizopus sp. CBMAI 1127 was very similar to that obtained with commercial lipase. The present study also evaluated antimicrobial and emulsifying properties of this ester. Emulsifying capacity of the synthesized oleyl oleate was lower than Tween 80 and sodium dodecyl sulfate, and no antimicrobial activity was observed.
Caroline Alves Breda,Daniella Lury Morgado,Odílio Benedito Garrido Assis,Marta Cristina Teixeira Duarte 한국고분자학회 2017 Macromolecular Research Vol.25 No.11
Chitosan is a polysaccharide with excellent film forming ability widely evaluated as active packaging and edible coatings. Chitosan has good antimicrobial activity in gel form; however, in a solid state (film format), a reduction in this activity can occur due to spatial arrangement of the chains in the polymer matrix. Small amounts of natural compounds could then be added to the film formulations to improve both antifungal and antibacterial properties. One possible additive is the “pequi” (Caryocar brasiliense Comb.) peel ethanolic extract (PPE), which forms homogenous blend with chitosan and has proved antimicrobial activity. In this study the preparation of chitosan-PPE was evaluated concerning the effect promoted in the film structure due PPE incorporation. Films processed by casting were analyzed by Fourier transform infrared spectroscopy (FTIR), microscopy, X-ray diffraction, mechanical and thermal properties, water vapor permeability (WVP) and surface wettability. FTIR analysis indicates interactions between the phenolic compounds in the extract and the hydroxyl and amine groups present in the chitosan structure, by establishing a possible ester bonding between constituents. The presence of PPE resulted in a decrease of WVP and an increasing in hydrophobicity. The extract addition also reduced the film’s crystallinity along with a slight decrease of plasticity and lowering of the initial polymeric degradation temperature. However, the blend was characterized by a homogeneous matrix with smooth topography. The results suggest that PPE has good compatibility with chitosan, introducing small changes that do not alter the potential for medical or foodstuff applications.