In ancient times, Russians put frogs in milk barrels to prevent milk from spoiling quickly when exposed to air.

It can be said that the refrigerator is one of the greatest inventions of mankind. With this box that is almost as tall as a person's head, it has replaced almost all food preservation methods that are quite expensive in terms of both economy and space. Before the refrigerator was invented, ancient people used all kinds of preservation methods such as pickling, salting, pickling, smoking, etc. However, perhaps few people know about the rather strange way of preserving milk of ancient Russians: putting frogs in milk barrels.

Why did they do that? To find out the reason, chemist at Moscow University, Mr. A.T. Lebedev, has researched and discovered antibacterial chemicals on the skin of Russian Brown frogs that make milk difficult to be affected by bacteria. The above research has been published in the American Chemical Society's Journal of Proteome Research.

It is known that amphibians secrete antibacterial chemicals called peptides through their skin, helping them fight the growth of bacteria in humid environments. In previous studies, scientists have discovered 21 compounds that help with antibiotics and kill bacteria on frog skin. However, using modern techniques, Mr. Lebedev and his colleagues have found 76 more compounds with similar effects.

In the laboratory, the above compounds have resisted salmonella bacteria that cause cholera and staphylococcus (staphylococcus that causes infection and poisoning) quite well, even equivalent to current antibiotics. "These peptides could be useful in preventing antibiotic-resistant bacteria in future medicine," said Lebedev.