Why does garlic repel mosquitoes and prevent them from breeding?

It was garlic It is considered normal Mosquitoes Haunted for centuries. It is believed in popular culture that its pungent scent repel these things InsectsWhich, in addition to causing sleepless nights, transmit diseases such as dengue fever or malaria. Now, this belief has a scientific explanation.

A group of scientists from Yale University conducted a phytochemical analysis of 43 types of fruits and vegetables to identify natural compounds capable of interfering with the reproductive behavior of flying insects. To do this, the team used fruit flies, a species that often mates for food, as a model organism.

Based on this behavior, researchers hypothesized that some fruits and vegetables may contain substances capable of altering the reproductive processes of these insects. After exposing different samples to the pureed foods included in the experiment, they noticed that none of the products had an aphrodisiac effect. However, they found that garlic completely prevented mating and egg laying.

After this initial result, the researchers sought to determine the source of the effect and focused their attention on the effect of garlic on the flies’ senses of taste and smell. To this end, they conducted two experiments. In the first, they put the garlic puree in such a way that insects can only smell it; The second they let them taste it too. The results showed that taste was the factor that actually inhibited reproductive behaviors.

The team then conducted a chemical analysis of garlic to identify the compound responsible for this effect. They determined that diallyl disulfide was the element that caused the inhibition. In practice, this substance acts on a sensory receptor found in the fly’s taste organs, known as TrpA1.

The TrpA1 receptor acts as a sensor that triggers immediate rejection responses when it detects potentially harmful tastes. According to an article published In the Cell Journal, garlic specifically activates a group of bitter taste-sensitive neurons that contain this receptor. This activation not only leads to a physical avoidance response, but also changes it at the molecular level by modifying the expression of various genes.

Among the identified changes, a gene closely linked to the feeling of fullness stands out, suggesting that contact with garlic compounds directly interferes with biological processes that regulate appetite and feeding in these insects. The authors hypothesize that increased satiety appears to lead to behaviors that limit mating and reproduction, especially in females.

A natural repellent for many species

In addition to fruit flies, the experiments were repeated on other flying insects, including two species of mosquitoes that transmit diseases such as yellow fever, dengue and Zika virus, as well as the tsetse fly. In all cases, tests have shown that garlic can serve as an effective treatment for inhibiting reproduction.

The researchers’ findings indicate that this plant, Allium sativum It can be used as a tool to control various insect pests harmful to human health and agriculture.

“It is inexpensive and grows all over the world.” He said John Carlson, a professor at Yale University and co-author of the study. “The idea of ​​using it to ward off bloody creatures was suggested in 1897 by Bram Stoker in his novel Dracula“Maybe he was right.”

This story originally appeared on WIRED in Spanish It was translated from Spanish.