Enzymatic hydrolysis of salmon oil by native lipases: optimization of process parameters

In an attempt to concentrate the content of n-3 polyunsaturated fatty acids (n-3 PUFA) in the residual acylglycerol, salmon oil (n-3 PUFA content of 30.1%) was hydrolyzed with three kinds of native microbial lipases (Aspergillus niger, Rhizopus javanicus and Penicillium solitum). For each lipase, a response surface methodology was used to obtain maximum PUFA content and to optimize the parameters of enzymatic reactions with respect to important reaction variables; temperature (X1), amount of lipases (X2) and water/oil ratio (X3). Based on these results, optimal reaction conditions were established. Aspergillus niger lipase was the most effective in concentrating n-3 PUFA. The degree of hydrolysis (60%) led to an increase in the docosahexaenoic acid (DHA) content from 14.4% in the original oil to 34.0% (2.4-fold enrichment) in the residual acylglycerol under optimum conditions: enzyme concentration of 500 U g-1 oil, reaction temperature of 45 ºC and water/oil mass rate of 2:1 (m/m) after 24 h reaction.Três lipases microbianas nativas (Aspergillus niger, Rhizopus javanicus e Penicillium solitum) foram utilizadas na hidrólise do óleo de salmão (teor de AGPI n-3 de 30,1%) com o objetivo de concentrar o conteúdo de ácidos graxos poliinsaturados n-3 (AGPI n-3) nos acilgliceróis residuais. A metodologia de planejamento experimental e análise de superfície de resposta foi usada para se chegar às condições otimizadas de cada reação enzimática, utilizando as seguintes variáveis; temperatura (X1), quantidade de lipase (X2) e taxa de água/óleo (X3). Com base nos resultados do planejamento, a lipase de Aspergillus niger foi a mais eficiente na concentração dos AGPI n-3, sendo que as condições ótimas de reação foram: concentração de enzima de 500 U g-1 óleo, temperatura 45 ºC e taxa de água/óleo de 2:1 m/m após 24 h de reação. O grau de hidrólise (60%) conduziu a um aumento do conteúdo de ácido docosahexaenóico (DHA) de 14,4% para 34,0% (enriquecimento de 2,4 vezes) nos acilgliceróis residuais após a hidrólise do óleo de salmão.117124Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Restricted skew-morphisms on matrix algebras

LBK

Gender Dynamics in a Masculine Professional Context: The Case of the Portuguese Air Force

This article aims to understand the experiences of women working in the Portuguese Air Force, a traditionally male professional environment, and the perspectives of their male counterparts on the subject, considering women’s minority status and symbolic gender asymmetries in the military. This study draws on 16 semi-structured interviews with Air Force personnel, evenly split by gender. Findings reveal four main themes that convey awareness that the Air Force is still a masculine world, perceptions of gender dynamics in the Air Force, barriers to equality, and strategies to address the situation. Although gender equality is formally in place in the Air Force, women continue to face obstacles that hinder their career advancement and ensure that their professional experiences differ from those of their male counterpartsinfo:eu-repo/semantics/publishedVersio