Flow cytometry as a rapid analytical tool to determine physiological responses to changing O2 and iron concentration by Magnetospirillum gryphiswaldense strain MSR-1

Magnetotactic bacteria (MTB) are a diverse group of bacteria that synthesise magnetosomes, magnetic membrane-bound nanoparticles that have a variety of diagnostic, clinical and biotechnological applications. We present the development of rapid methods using flow cytometry to characterize several aspects of the physiology of the commonly-used MTB Magnetospirillum gryphiswaldense MSR-1. Flow cytometry is an optical technique that rapidly measures characteristics of individual bacteria within a culture, thereby allowing determination of population heterogeneity and also permitting direct analysis of bacteria. Scatter measurements were used to measure and compare bacterial size, shape and morphology. Membrane permeability and polarization were measured using the dyes propidium iodide and bis-(1,3-dibutylbarbituric acid) trimethine oxonol to determine the viability and ‘health’ of bacteria. Dyes were also used to determine changes in concentration of intracellular free iron and polyhydroxylakanoate (PHA), a bacterial energy storage polymer. These tools were then used to characterize the responses of MTB to different O2 concentrations and iron-sufficient or iron-limited growth. Rapid analysis of MTB physiology will allow development of bioprocesses for the production of magnetosomes, and will increase understanding of this fascinating and useful group of bacteria

Improvement of lignocellulosic biomass conversion by optimization of fungal ligninolytic enzyme activity and molasses stillage supplementation

Fungal treatment of lignocellulose is an ecologically and economically acceptable method. However, it needs improvement to increase the hydrolysis rate. A novel combination of multiple response optimization of ligninolytic activity ofTrametes hirsutaF13 and supplementation of the lignocellulosic substrate (beechwood sawdust) with sugar beet molasses stillage was employed to improve and manage the desired type of fungal ligninolytic activity leading to a significant enhancement of biomass saccharification. Obtained optimal cultivation conditions (molasses stillage concentration, 13%; substrate moisture, 63%; and temperature, 25 degrees C) provided the desired combination of laccase and manganese-dependent peroxidase activity, and maintained the activities longer and at higher values (51.5 +/- 3.5 U/L and 91 +/- 4.24 U/L, respectively) than the conditions without molasses stillage (21.5 +/- 2.12 U/L and 31.5 +/- 4.9 U/L, respectively). Enzyme hydrolysis of the substrate treated for 7 days in the presence of molasses stillage released 20.54 +/- 0.80 mg/mL fermentable sugars, and 63.58 +/- 1.47 mg/mL from 18-days treated substrate, while sugar concentrations released from the substrates pretreated without the supplementation were 16.84 +/- 0.30 mg/mL and 53.63 +/- 2.16 mg/mL, respectively. The proposed new approach of the lignocellulose supplementation with sugar beet molasses stillage and manipulation and improvement of fungal ligninolytic activity proved to be a promising solution for the enhancement of lignocellulose bioconversion

Investigación educativa en las aulas de primaria

Reúne trabajos derivados de la experiencias de diversos docentes en educación primaria en los siguientes temas: Tecnología de Información y Comunicación, educación inclusiva, enseñanza de la música, educación física, enseñanza de la historia, acoso escolar, auto-evaluación, métodos de enseñanza, inteligencia emocional, percepción del alumno, marco cognitivo en comprensión lectora y comunicación escuela-familia

Opportunities for new-generation Ganoderma boninense biotechnology

Plant pathogenic fungi are significantly impacting global food security, causing a tremendous decline in crop yield and production. Strategies to identify fungal pathogenicity/virulent factors remain a grand challenge in biotechnology especially in the quest for an effective solution involving resistance, protection and management. The basidiomycete, Ganoderma boninense, causes basal stem rot (BSR) in oil palm trees involving lignin biodegradation. In Southeast Asia, BSR severely affects oil palm production with ongoing economic losses. The disease is deemed a serious agricultural threat to developing, or newly industrialized, countries such as Malaysia, Papua New Guinea and Indonesia. In this chapter, we discuss the biology and pathogenic nature of G. boninense with respect to its host defence response, lignification. We present an explicit overview of the G. boninense-oil palm pathosystem and thereby provide critical information on feasible strategies available for G. boninense control. In addition, current improvements and future prospective for new-generation biotechnology in respect to G. boninense are discussed.(undefined)info:eu-repo/semantics/publishedVersio