Particular challenges exist for science education in the developing world, where limited resources require curricula designed to balance state-of-the-art knowledge with practical and political considerations in region-specific contexts. Project-based biology teaching is especially difficult to execute due to high infrastructural costs and limited teacher training. Here, we report the results of implementing short, challenging, and low-cost biology courses to high school and college students in Bolivia, designed and taught in collaboration between scientists from developed nations and local science instructors. We find our approach to be effective at transmitting advanced topics in disease modeling, microscopy, genome engineering, neuroscience, microbiology, and regenerative biology. We find that student learning through this approach was not significantly affected by their background, education level, socioeconomic status, or initial interest in the course. Moreover, participants reported a heightened interest in pursuing scientific careers after course completion. These results demonstrate efficacy of participatory learning in a developing nation, and suggest that similar techniques could drive scientific engagement in other developing economies.

The interaction between quinoa proteins isolate (QP isolate) and the negatively charged polysaccharide ι-Carragennan (Carr) as a function of pH was studied. Experimental measurements as turbidity, hydrophobic surface, ζ-potential, and hydrodynamic size were carried out. Associative interaction between QP and Carr was found in the pH range between 1 and 2.9. When both molecules are negatively charged (pH>5,5), a pure Coulombic repulsion regime is observed and the self-association of QP due to the Carr exclusion is proposed. In the intermediate pH range, the experimental data suggests that the charge regulation mechanism can overcome the electrostatic repulsion that may take place (and an attraction between QP and Carr can still be observed). Computational simulations by means of free energy derivatives using the Monte Carlo method were carried out to better understand the interaction mechanism between QP and Carr. QP was modeled as a single protein using one of the major proteins, Chenopodin (Ch), and Carr was modeled as a negatively charged polyelectrolyte (NCP) chain, both in the cell model framework. Simulation results showed attractive interactions in agreement with the experimental data.

The effect of carrageenan on the acid-induced aggregation and gelation conditions of quinoa proteins

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Orange peels, soybean hulls, Ilex paraguariensis and Platanus x hispanica were evaluated as solid substrates in order to produce peptidases from Aspergillus niger NRRL3 (PAN) under solid-state fermentation. The mixture of soybean hulls and orange peels enabled fungal development and showed the highest peptidase production. The optimal conditions for PAN production were found to be as follows: soybean hulls/orange peels mass ratio, 0.25; initial pH, 7.05; K 2 HPO 4 43.5 g/L and 4.03 g/L NaNO ; inoculation with 5000 conidia per 3g of solid substrate; incubation conditions, 30°C for 5 days. Under these conditions, the peptidase activity was 1000 ± 100 AU/mL. PAN concentration was performed by adsorption on a DEAE-cellulose matrix. The subsequent purification was carried out by gel filtration on Sephadex G-100, with a global purification factor of about 9. PAN proved to belong to the serinetype of peptidases, its highest peptidase activity being at 65 °C. However, proteolysis at 60 °C proved more suitable due to the differences in the inactivation rate. Besides, PAN showed high stability over a pH range of 4 to 11. Taking all this into account, we herein describe the production and purification of a serine peptidase from Aspergillus niger NRRL3 for the first time.

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Project-based learning (PBL) has long been recognized as an effective way to teach complex biology concepts. However, not all institutions have the resources to facilitate effective project-based coursework for students. We have developed a framework for facilitating PBL using remote-controlled internet-connected microscopes. Through this approach, one lab facility can host an experiment allowing simultaneous interaction by many students worldwide. Experiments on this platform can be run on long timescales and with materials that are typically unavailable to high school classrooms. This allows students to perform novel research projects rather than just repeat standard classroom experiments. To investigate the impact of this program, we designed and ran six user studies with students worldwide. All experiments were executed in Santa Cruz and San Francisco, California, with observations and decisions made remotely by the students using their personal computers and cellphones. In surveys gathered after the experiments' conclusion, students reported increased excitement for science and a greater desire to pursue a career in STEM. This framework represents a novel, scalable, and effective PBL approach that has the potential to democratize biology and STEM education around the world.