Abstract Empty fruit bunch fiber (EFBF) is a lignocellulosic waste generated by the palm oil agribusiness. The amount of EFBF produced is equal to the oil obtained, and it can be used as raw material to obtain biocomposites. The objective of this work is to fragment the EFBF employing pressurized fluids in a semi-continuous system to obtain different biocomposites. For this, pure water and a mixture of water/carbon dioxide were employed as solvent to obtain sugar monomers and a mixture of compressed water/ethanol (1:1 vol.) to obtain crystalline cellulose. The experiments were conducted in the temperature range of 120 to 240 ºC, using reaction times between 5 and 15 min at 60 bar, and solvent flow rate of 0.75 mL.min-1. A maximum of 30.47 mg.mL-1 of xylose was obtained at 210 ºC for 15 min of reaction with pure water as solvent. The best condition to obtain crystalline cellulose was 240 ºC for 30 minutes of reaction, obtaining 38.2% of cellulose from palm oil EFBF.

Abstract Considering the microbial safety of consumption of raw foods (Asian food), this study aimed to explore the inactivation S. aureus in raw salmon by supercritical CO2 treatment (SC-CO2). For this purpose, experimental design methodology was employed as a tool to evaluate the effects of pressure (120-220 bar), the depressurization rate (10 to 100 bar.min–1) and the salmon:CO2 mass relation (1:0.2 to 1:1.0). It was observed that the pressure and the depressurization rate was statistically significant, i.e. the higher the system pressure and depressurization rate, the greater the microbial inactivation. The salmon: CO2 mass relation did not influence the S. aureus inactivation in raw salmon. There was a total reduction in S. aureus with 225 bar, a depressurizing rate of 100 bar.min–1, a salmon: CO2 mass relation of 1:0.6, for 2 hours at 33 °C.

Mesoporous silica supports (aerogels) were used to immobilize Burkholderia cepacia lipase (BC) by encapsulation (EN or ENIL), physical adsorption (ADS or ADSIL) and covalent binding (CB or CBIL) into or onto the aerogel modified with protic ionic liquid (PIL). Yield immobilization (Ya) and operational stability were determined by the hydrolytic reaction of olive oil. Ya (37% to 83% by physical adsorption) and operational stability (2 to 23 batches by encapsulation) increased when the support was modified with PIL. For immobilized derivates observed by the BET method, in this case ADS and CB for ADSIL and CBIL, increased pores size was observed, possibly due to the higher amount of BC immobilized conferring Ya and operational stability. This effect was probably attributed to the entry of the enzyme into the pores of the silica aerogel structure. SEM images showed a change in the structure and properties of immobilized lipase derived with PIL. A characteristic FTIR band was obtained for the silanol groups and amides I, IV and V, demonstrating the efficiency of immobilization of BC. The most efficient biocatalysts were ADSIL with regard to yield immobilization and ENIL for operational stability.

Lipase from Burkholderia cepacia was immobilized in a silica matrix and dried in high pressure carbon dioxide media (aerogel). The protic ionic liquid (PIL) was used in the immobilization process by encapsulation. The objective of this work was to evaluate the influence of the drying technique using supercritical carbon dioxide in biocatalysts obtained through the sol-gel technique by evaluating temperature and pressure and, after selecting the best drying conditions, to investigate the application of the technique for the biocatalyst using ionic liquid as an additive in the immobilization process. The results for immobilized biocatalysts showed that the best conditions of pressure and temperature were 100 bar and 25 ºC, respectively, giving a total activity recovery yield of 37.27% without PIL (EN) and 44.23% with PIL (ENLI). The operational stability of the biocatalysts showed a half-life of 11.4 h for ENLI and 6 h for EN. Therefore, solvent extraction using supercritical CO2, besides shortening drying time, offers little resistance to the immobilization of lipases, since their macropores provide ample room for their molecules. The use of the ionic liquid as an additive in the process studied for the immobilization of enzymes produced attractive yields for immobilization and therefore has potential for industrial applications in the hydrolysis of vegetable oils.

5-(Oxiran-2-ilmetil)-1,3-benzodioxol ou epóxi-safrol (SO) vem sendo estudado ao longo dos anos devido a suas propriedades dependentes da concentração, como indução à apoptose e transdiferenciação celular. A coprecipitação do SO com um polímero biodegradável e biocompatível, poli(3-hidroxibutirato-co-3-hidroxivalerato) (PHBV), foi realizada utilizando a técnica de dispersão de solução aumentada por fluídos supercríticos (SEDS). Um planejamento fatorial 2(4-1) foi realizado para investigar os efeitos das condições experimentais (pressão, vazão de solução e de antissolvente e concentrações de PHBV e SO) na eficiência do processo e na morfologia dos coprecipitados. Para o material obtido SO/PHBV, foram observadas formas esféricas e fibrosas, sendo as morfologias dependentes das condições experimentais. Os mecanismos de liberação controlada de epóxi-safrol para os materiais esféricos foram diferentes dos materiais fibrosos. Análise térmica mostrou uma diminuição na temperatura de máxima velocidade de degradação (Tmax) em relação ao PHBV, atribuída à presença de SO e à morfologia da amostra.

In recent years, 5-(oxiran-2-ylmethyl)-1,3-benzodioxole or safrole oxide (SO) has been widely studied due to its concentration dependent properties, such as cellular apoptosis inducing activity and cell transdifferentiation. Coprecipitation of SO with a biodegradable and biocompatible polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), were performed using solution enhanced dispersion by supercritical fluids technique (SEDS). A 2(4-1) factorial design was carried out to investigate the effect of processing parameters (pressure, solution flow, anti-solvent flow and concentrations of PHBV and SO) on the process efficiency and microparticle morphology. Both fibrous and spherical shapes were observed for coprecipitated SO/PHBV, which were dependent on the experimental-processing conditions. Controlled release mechanisms of SO to spherical materials were different from fibrous materials. Thermal analysis showed a decrease in the temperature of maximum weight loss rate (Tmax) of PHBV, attributed to the presence of SO and sample morphology.