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Green synthesis of silver nanoparticles (AgNPs) provides the alternative method with cost effectiveness and the eco-friendly process by using natural biomolecules as reducing and stabilizing agents. Alternative to the most studies of plant extracts, this work demonstrated a use of egg extract of apple snail (Pomacea canaliculata) for an eco-friendly production of AgNPs. The extract contained at least six proteins with the molecular weight in a range of 24-65 kDa that exhibited the reducing activity. The dispersive AgNPs were produced in the reaction containing only the extract and silver nitrate, as determined by the characteristic surface plasmon resonance peak of silver at 412 nm. The synthesized AgNPs were spherical with the average diameter of 9.0 ± 5.9 nm. The X-ray diffraction pattern and selected area electron diffraction (SAED) analyses confirmed the face-cubic centre (fcc) unit cell structure of AgNPs. The synthesized AgNPs exhibited the antibacterial activity against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Results of this work clearly showed the potential use of the egg extract of apple snail for a green synthesis of small size AgNPs exhibiting the antibacterial activity.

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Technology and validation methods for producing biodiesel have been updated and have kept advancing. Creative raw materials used in producing environmentally friendly biodiesels have also attracted interest from scientists. Thus, learning and teaching methods on biodiesel production at the high school level need to be up to date. However, there are expensive instruments required in performing experiments. This limitation reduces students' chances in integrating their chemical knowledge with the current situation. This study aims to develop a STEAM activity on biodiesel production by using waste vegetable cooking oil (WVCO) for high school students in Thailand. A simple and inexpensive experiment is described. The produced biodiesel was qualitatively analyzed by using thin-layer chromatography (TLC) and compared with a standard biodiesel. The basic science process skills (BSPS) and the learning achievement on biodiesel production of 60 students from a high school in Nakhon Phanom province were assessed. The findings of this study revealed that there were benefits to including art in this STEAM activity, including encouraging effectiveness in communicating scientific ideas of the students with the lowest BSPS score and encouraging creative thinking of the students while practicing their science laboratory skills. The satisfaction of the students toward the STEAM activity was at a good level. Guidance for teachers to further implement the STEAM activity in schools is provided.