Characterization of novel thermostable polygalacturonases from Penicillium brasilianum and Aspergillus niger.

The aim of this research was the partial characterization of polygalacturonase (PG) extracts produced by a newly isolated Penicillium brasilianum and Aspergillus niger in submerged fermentation. The partial characterization of the crude enzymatic extracts showed optimum activity at pH 5.5 and 37 °C for both extracts.

Control of sp. on the Surface of Italian Salami Using Essential Oils.

The goal of this study is to evaluate the effects of rosemary, salvia, oregano and clove oils at volume fractions of 1000, 750, 500, 250, 100, 50, 26, 10 and 5 µL/mL (100, 75, 50, 25, 10, 5, 3, 1 and 0.5%) on the growth of contaminating fungi in salami. The effect of the oils against fungal growth was indicated by zones of inhibition.

Synthesis of a hybrid polymer-inorganic biomimetic support incorporating in situ pectinase from Aspergillus niger ATCC 9642.

The hybrid alginate/gelatin/calcium oxalate (AGOCa) support was successfully synthesized through the biomimetic mineralization method for immobilization in situ of a pectinolytic extract from Aspergillus niger ATCC 9642 via entrapment technique. The efficiency of immobilization reached 72.7%.

Comparative lethality kinetic curves and predictive models of F-value for Listeria monocytogenes using different sanitizers.

The objective of this work was to evaluate the kinetic of inactivation of Listeria monocytogenes using peracetic acid, chlorhexidine, and organic acids as active agent, determining the respective D-, Z-, and F-values. From our knowledge, these important results from an industrial view point are not available in the current literature, mainly for organic acids, pointing out the main contribution of the present work. Lower D-values were obtained for peracetic acid and chlorhexidine, compared with the organic acids.

Ultrasound-assisted enzymatic transesterification of methyl benzoate and glycerol to 1-glyceryl benzoate in organic solvent.

The aim of this work is to report the enzymatic transesterification production of 1-glyceryl benzoate under ultrasound irradiation, using a commercial immobilized lipase, Novozym 435. Firstly, a preliminary evaluation was carried out at 2, 4 and 6h, at constant temperature of 50 °C, methyl benzoate to glycerol molar ratio of 1:1 and 5.5 wt% of enzyme concentration.

Enzymatic synthesis of ascorbyl palmitate in ultrasound-assisted system: process optimization and kinetic evaluation.

This work is focused on the optimization of reaction parameters for the synthesis of ascorbyl palmitate catalyzed by Candida antarctica lipase in different organic solvents under ultrasound irradiation. The sequential strategy of experimental design proved to be useful in determining the optimal conditions for reaction conversion in tert-butanol system using Novozym 435 as catalyst. The optimum production was achieved at 70°C, ascorbic acid to palmitic acid molar ratio of 1:9, enzyme concentration of 5 wt% at 3h of reaction, resulting in an ascorbyl palmitate conversion of about 27%.

Optimization of α-Terpineol production by the biotransformation of R-(+)-limonene and (-)-β-pinene.

The main objective of this work is to present the optimization of the biotransformation of R-(+)-limonene and (-)-β-pinene aiming at the production of α-terpineol by strains of fungal and yeasts previously isolated by our research group using the methodology of experimental design. New optimized experimental data on α-terpineol production by the biotransformation of R-(+)-limonene and (-)-β-pinene using newly isolated microorganisms are reported in this work. Conversion of about 1,700 mg/L was achieved when R-(+)-limonene was used as substrate and the newly isolated strain 05.

Insecticidal and repellency activity of essential oil of Eucalyptus sp. against Sitophilus zeamais Motschulsky (Coleoptera, Curculionidae).

Background: The objective of this work was to evaluate the insecticidal and repellent effect of essential oils of Eucalyptus dunnii, E. saligna, E. benthamii, E.

Screening of pectinase-producing microorganisms with polygalacturonase activity.

The aim of this work was to perform the screening of microorganisms, previously isolated from samples of agro-industrial waste and belonging to the culture collection of our laboratory, able to produce polygalacturonases (PG). A total of 107 microorganisms, 92 newly isolated and 15 pre-identified, were selected as potential producers of enzymes with PG activity. From these microorganisms, 20 strains were able to synthesize PG with activities above 3 U mL(-1).

Microbial oxidation of (-)-α-pinene to verbenol production by newly isolated strains.

Verbenol is a bicyclicbicycle secondary allylic alcohol, with pronounced camphor and mint flavor notes, mainly used as food flavoring. This compound is also used to control harmful insects, and hence has potential for using in agriculture, and is an intermediate in the synthesis of valuable perfume and medicinal substances. This work is focused on the microbial oxidation of (-)-α-pinene to verbenol production.

Enzyme-catalyzed production of 1-glyceryl benzoate in compressed n-butane.

The aim of this work is to report the enzymatic transesterification production of 1-glyceryl benzoate in compressed n-butane, using a commercial immobilized lipase, Novozym 435. For this purpose, reaction experiments were performed on the basis of phase equilibrium data of the system methyl benzoate/n-butane, measured using the static synthetic method with a variable-volume view cell in the temperature range of 313.15-343.

Isolation and screening of microorganisms for R-(+)-limonene and (-)-beta-pinene biotransformation.

This work is focused on the biotransformation of R-(+)-limonene and (-)-beta-pinene to bioflavor production. To carry out the present study, 405 microorganisms were tested for their ability to bioconvert the substrates. From the isolated microorganisms, 193 were selected in the prescreening using mineral medium for limonene degradation.

Microorganism screening for limonene bioconversion and correlation with RAPD markers.

The use of microorganisms for biotransformations of monoterpenes has stimulated the biotechnological market. Aiming at the highest efficiency in the process of strains screening, the application of molecular biology techniques have been proposed. Based on these aspects, the objective of this work was to select different strains able to convert limonene using fermentative process and random amplified polymorphic DNA (RAPD) markers.

Biotransformation of (-)beta-pinene by Aspergillus niger ATCC 9642.

The main objective of this work was to investigate the biotransformations of (-)alpha-pinene, (-)beta-pinene, and (+) limonene by Aspergillus niger ATCC 9642. The culture conditions involved--concentration of cosolvent (EtOH), substrate applied, and sequential addition of substrates were--investigated. Adaptation of the precultures with small amounts of substrate was also studied.