Beauveria bassiana submerged spores for control of two-spotted spider mite (Tetranychus urticae Koch (Acari: Tetranychidae)): production, stability, and virulence.

In this study, IBCB 66, IBCB 868, and CBMAI 1306 isolates of Beauveria bassiana were grown in liquid culture for 4 days, leading to elevated submerged spores (SS) levels. The influence of the addition of different glycerol concentrations (0, 3, and 6%) (v/v) in the liquid culture was investigated regarding the stability (at 4 and 27 °C) of dried formulations. The virulence of SS was compared with aerial spores (AS) against Tetranychus urticae (Koch) (Acari: Tetranychidae). The results demonstrate the potential of using SS to control T. urticae. CBMAI 1306 and IBCB 868 isolates caused T. urticae mortality rates of 91.11% and 88.89% 5 days after treatment, respectively, when applied at concentrations of 1 × 108 SS mL-1. The median Lethal Time (LT50) values for these strains were 2.64 and 2.61 days, respectively. The dried formulations showed potential acaricidal activity. Higher glycerol concentrations in the liquid culture medium reduced formulation stability at 27 °C.

Upscale and characterization of lignin-modifying enzymes from Marasmiellus palmivorus VE111 in a bioreactor under parameter optimization and the effect of inducers.

Testing different pHs, dissolved oxygen concentrations and temperatures, plus the addition of inducers, to optimize ligninolytic enzyme activity, resulted in increased production of laccases, total peroxidases and manganese peroxidases on the order of 2.1-fold, 4.6-fold and 10-fold, respectively; laccases reached 6588 U/mL, total peroxidases reached 3533 U/mL and manganese peroxidase achieved 60 U/mL. Furthermore, an increase in laccase volumetric productivity and in its specific activity was verified. The addition of inducers, such as copper sulphate and manganese sulphate, improved enzymatic activity. In addition, a new previously unidentified laccase isoform was documented by zymography. The present work successfully increased the production of ligninolytic enzymes.

Phenol removal by laccases and other phenol oxidases of Pleurotus sajor-caju PS-2001 in submerged cultivations and aqueous mixtures.

In this work, phenol removal from aqueous solutions by Pleurotus sajor-caju PS-2001 phenol oxidases was assessed under different conditions. In stirred-tank reactor (STR), 77, 82, 92 and 36% of removal were attained when initial concentrations of 1.0, 2.0, 3.0 and 4.0 mmol L-1 phenol, respectively, were used. Among the different enzymes produced by this fungus, phenol removal seems to be related to the activity of laccases that attained maximum values between 33 and 91 U mL-1 in STR. With an internal-loop airlift reactor (ILAR), phenol concentrations of 1.0, 2.0, 3.0, 4.0 and 5.0 mmol L-1 were evaluated, and removal of 70, 76, 82, 77 and 82%, respectively, were observed. In ILAR, however, superior maximum titres of laccases were quantified (80-285 U mL-1). Crude enzyme broths have also been tested for phenol removal from 3.0 mmol L-1 aqueous solutions, the best result (55% of removal) being obtained at pH 3.2 and 30 °C, without agitation, using 60 U mL-1 laccases. According to the data presented, phenol can be efficiently removed from liquid media in submerged cultures of P. sajor-caju PS-2001 even when carried out in a simple pneumatic reactor, whereas significantly less amount of the pollutant is degraded when a crude enzyme broth is used.