More than 1,000 primary and secondary school students from northern Portugal took part in the 4th edition of International Microorganism Day, organized by the Faculty of Biotechnology (ESB) of the Universidade Católica Portuguesa, in Porto. The initiative invited young people to explore the invisible world of microbiology through scientific experiments, playful activities, and outdoor laboratory demonstrations.
Featuring around 30 experimental activities, the event was led by professors and students from ESB’s undergraduate, master’s, and doctoral programmes, as well as researchers from the Centre of Biotechnology and Fine Chemistry (CBQF). Over its four editions, International Microorganism Day has already engaged more than 1,600 students.
“This initiative is now in its fourth year, and we see more and more young people joining us to explore the invisible world of microorganisms — tiny beings that shape our planet, our health, and even the food we eat,” says Paula Castro, Director of the Faculty of Biotechnology. “This faculty has a long-standing history in this field: the first undergraduate degree in Microbiology in Portugal was created here, and in our research centre, biotechnology and microbiology are part of daily life.”
Science in action
In an outdoor laboratory setting, participants discovered the essential role of microorganisms in the environment, food production and safety, human health, and the development of innovative products with industrial and scientific applications. Among the most popular activities were the Foldscope, a paper microscope accessible to everyone, and Bio&Tec, a card game designed to challenge students on microbiology concepts.
Students also engaged in rapid identification tests (“Who am I?”), microscopic observation of microorganisms in yogurt, and demonstrations of microorganisms’ role in wastewater treatment, soil health, and aquaponics systems where fish and plants are cultivated together.
Gastronomy meets science
Gastronomy was another highlight, with yogurt encapsulation experiments inspired by molecular gastronomy and sensory analyses that revealed the role of fungi in producing different types of cheese. Students also observed baker’s yeast under the microscope and tested its cell viability, understanding the crucial contribution of microorganisms to food production.
Learning through play
The playful dimension included games such as Cluedo: Micro Edition, presented by Frulact S.A., where participants identified the microorganism responsible for food contamination; Mission Antibiotic, which focused on the correct use of antibiotics; and microbiology-themed versions of classic games like Tic-Tac-Toe and Guess Who?
“It was a day of awareness and hands-on contact with different microorganisms in a laboratory context, but in a relaxed outdoor environment,” highlighted Joana Barbosa and Joana Cristina Barbosa, researchers and members of the organizing committee.
At the end of each session, students received gifts offered by ESB, BlueDesignAliance (BDA), and the participating companies Frulact S.A. and MicroHarvest, both of which work with microorganisms in their processes. They also took home Foldscopes, Bio&Tec games, and even plush microorganisms offered by GiantMicrobes.
“By opening the faculty to primary and secondary school students, we fulfil our mission of promoting scientific literacy among younger generations. In STEM areas, which the country urgently needs, we cannot wait until students arrive at university to spark their interest and motivation for high-quality knowledge,” emphasizes Paula Castro.
“We aim to show how microorganisms, although invisible to the naked eye, are an integral part of our lives, playing essential roles in our food, health, and environment. In fact, only 43% of the cells in the human body are human – the rest are microorganisms,” the researchers add.
The 4th International Microorganism Day took place on 24 September, as part of the celebration of International Microorganism Day (17 September), marking the date in 1683 when Antonie van Leeuwenhoek first described these organisms to the Royal Society of London.
