Students make hemostatic bandages from perilla leaf

Perilla leaf extracts has been used by two students from Nhan Viet High School to make bandages to stop bleeding.

Perilla leaf, a herb of the mint family, Lamiaceae, is familiar to Vietnamese. In Vietnamese cuisine, it is usually eaten as a garnish in rice vermicelli and some other dishes. 

People believe that the leaf has many medical uses. Sources said perilla oil is a very rich source of the essential nutritional omega-3 fatty acid alpha-linolenic acid. Vietnamese drink the leaf extract when they catch a cold. They believe that perilla leaf contains a substance that can help stop bleeding.

Nguyen Tran Nhat Tan and Doan Nguyen Vien Than, the two students of Nhan Viet High School in Tan Phu district, HCM City, decided to exploit the styptic of perilla leaf.

According to Tan, the first-aid bandages available in the market are used mostly to stop bleeding for small and not serious wounds. There is no effective product for large wounds.


“An idea flashed through our mind that we needed to create a kind of bandage which can help stop bleeding for open wounds, while they still must be handy, compact and easily carried away in bag, wallet, or first aid box,” he said.

Tan and Than then bought perilla leaves, cleaned them and ground them in a blender. After that, they put 5 percent into the well-kneaded perilla leaves, put the mixture in a 5-liter tank and left the tank for two days in dry and cool place.

Two days later, they filtered the mixture to get extracts, changed the solvent and soaked for another two days.

They had two choices for the next step. They could to let the solvent evaporate within 10 days until they could get highly condensed solution. This was a simple method, but it took time.

They could also use pressure and heat to make solvent evaporate. This allowed speeding up of the evaporation process, but it required rotary evaporator.

After they got the extract, they pumped the extract into bandage and tested the hemostasis capability.

According to Tan, experiments showed that the bandage with perilla extracts prevented bleeding after 10-20 seconds on a glass surface and sterile gauze.
The figure was 1-3 minutes in normal conditions or alcohol.

Bui Gia Hieu, headmaster of Nhan Viet High School, said using perilla leaf’s extract was an original idea, and the product would be useful in the healthcare sector.

“The bandage uses materials from nature, so it is safe and environment friendly,” he said.

Nhan Viet has promised to help the students to develop the product commercially.