This volume contains peer-reviewed full-text papers, short reports of which were presented on the 2nd International Seminar on Science and Technology (ISSTEC), November 25, 2019, in Yogyakarta, Indonesia. Published articles cover a wide range of scientific research results and engineering solutions in the area of materials science, materials chemistry, chemical technologies for environmental protection, pharmacology, the food and perfume industry, synthesis of nanoparticles.