Oregano against fungi

Aromatic compounds in oregano can stop food spoilage from fungi.

Every year up to 25% of fruits and vegetables are thrown away due to fungal diseases. In agricultural production, mainly synthetic fungicides are used against fungi, but they can cause serious damage to human health and the environment. Fortunately, plants have developed many methods of fighting disease, and nature has many great recipes for our health and to ensure a good harvest of agricultural crops.

This activity helps to explain how the cell wall of mold can be disturbed by the action of a biofungicide.

1. Start y explaining that every living organism is made up of cells and every cell is made up of a cell wall and the inside of the cell. If the cell wall is broken, the cell dies. This also applies to mold that we do not like to see, for example, on fruit or on food in the refrigerator. However, nature can disrupt the wall of mold cells by the action of various substances found in various aromatic herbs (oregano, motherwort, mint).
2. Divide pupils into two groups: two thirds of the pupils will represent the cell wall of the mold, hold hands and form a line. The rest of the pupils, representing the ethereal/volatile substances of the biofungicide, get one or two paper balls each. They form a line and stand 5 to 10 metres (depending on age) from the first line, “the cell wall”.
3. Pupils from the 2nd group try to hit the children from the 1st group one by one with paper balls. The pupils from the first group who are hit are eliminated from the game and step aside - the remaining pupils hold hands again.
4. If more than half of the pupils, representing the cell wall, are eliminated, the cell breaks up and the group of pupils - throwers (representing the biofungicide) wins. If more than half of the pupils remain unaffected, the biofungicide has 'failed.
5. Pupils change roles and repeat the activity.
6. Discuss the results. The pupils in the cell wall represented particles that dissolve during the reaction with the biofungicidal substance, causing the cell wall to be damaged and its death. The paper balls represented molecules of volatile substances that only had one or two opportunities to attack the cell wall (they 'it' only the sensitive part of the cell wall (lipid) that they can break down). This sensitive component of the cell wall was represented by the pupils in the row.

Plants cannot run away from danger like animals, so they have developed other defense strategies. Oregano, thyme and other plants contain active substances that help them defend themselves. For example, oregano essential oil has been shown to be effective against fungi, bacteria and viruses. Due to the high content of volatile aromatic organic compounds thymol and carvacrol, it destroys molds (a type of fungus) by breaking down their cell membranes.

Simple explanation

There is probably no one among us who does not like strawberries. Maybe some of you grow them in the garden or on the balcony. Strawberries are very healthy and tasty, but they are prone to fungal diseases, especially when it rains a lot. That's when they need our help. Fortunately, instead of harmful chemical preparations, we can use biological ones that use antifungal substances from plants, for example oregano (natural gardeners have long used various plant extracts or natural sprays to protect crops).

More detailed explanation

Do you know which spice gives pizza its typical taste? You can probably guess that it is fragrant oregano. But oregano is more than just a spice. Imagine, even in ancient Greece and Rome, warriors rubbed their wounds with medicinal oregano oil to prevent infection. Phytochemicals (such as thymol or carvacrol) in oregano oil are so powerful that they can destroy viruses, bacteria and fungi. Antifungal property of oregano is used in gardening, farming and for medicinal purposes.

Scientists are exploring the possibilities of using the antibacterial and antifungal effects of plants to develop smart antifungal formulas. For example, the Turkish company NANOMIC has developed a biofungicide in capsules unsing nanotechnology, which makes it easy to apply. Since the capsule only opens when the pH drops i.e. when the plant is attacked by a fungal disease, the natural fungicide works when it is most needed and effective.

New studies from the USA show that an integrated pest control system using modern preparations containing carvacrol can effectively protect vegetables from bacterial, fungal and viral pathogens. (Read more).

Some STEAM opportunities include:

• Broadening the scientific view of the world around.
• Testing and developing ideas about everyday phenomena.
• Asking questions.
• Observe life-cycle changes of plants in the local environment.
• Using straightforward scientific evidence to answer questions or to support their findings.

Read about different ways to avoid fungal diseases on plants (read more here).

Is moldy food safe to eat? (read more here).