Team:CIEI-BJ/Description
Description
There is a stunning amount of mosquito repellents on sale in the market, but are they safe enough?
1)Repellent incense:
In common repellent incense, the effective ingredients comprise of permethrin pesticide, organic filler, binding agent, dye, and other addition agent. Therefore, the smoke produced in the combustion of repellent incense contains many compounds that are harmful to the human body. Asthma can be caused in a brief period of intake, cancer is also possible with a longer interval of exposure. Furthermore, incomplete combustion of repellent incense’ backing material can produce carcinogen and other upper respiratory stimulant, which will result in poisoning the nervous system.
2)Floral water:
A great amount of floral water on sale added mosquito-repellent ingredients which are mostly diethyltoluamide (DEET) and Dimethyl phthalate (BAAPE). They affect mosquitoes’ smell sensing mechanism. This jams the mosquitoes’ ability to locate their “prey”. However, DEET’s negative devastating effect on human nervous system is now being discovered. On the other hand, most factories didn’t publicly state the alcohol content percentage (the Internet says it to be about 70%). There are risks of alcohol being lit up with fire.
3)Mosquito repellent band:
This bands use high-grade silica gel combined with natural oils extracted from lemongrass, lavender, lilac and other plants. It gives off a pleasant odor. The effective repellent ingredient is citronellal from citronellal essence oil. It has strong effect in repelling mosquitoes and insects, but irritates eyes, skin and respiratory system.
Explaination
Our team is working on a way to produce citronellol in a synthetic biology way. Citronellol is a rose-scented, harmless compound. It is often used as edible essence (the safety of this compound can be clearly seen from this). Currently, producing citronellol biologically are broken into two parts. The first step is planting geraniol-synthase gene (GES) into engineering bacteria. Provided with glucose, the bacteria will produce geraniol. Second, citronellol synthase gene (old yellow enzyme, OYE) is planted into yeast, where geraniol will be transformed to citronellol. Due to the transferring of material between different organisms, efficiency is hard to achieve. In our project, we will plant both GES and OYE into yeast, saving the trouble of transferring between organisms, which will mitigate the losses of material and greatly reduce the cost of production. We hope to create a simple and effective approach to the production of citronellol for its the promotion as a mosquito repellent.
