BAMBOO PYROLIGNEOUS ACID AS A NOVEL INSECTICIDE, ITS MOSQUITO REPELLENCY ACTIVITY, CHEMICAL COMPONENTS AND SAFETY TOWARDS ANIMALS

Mosquitoes transmit pathogens which cause human and mammalian diseases. We employed several practical and multidisciplinary approaches to discover a new natural mosquito repellent. The active ingredient tests revealed that bamboo vinegar (BV) showed 91% protective efficacy. The forearm skin landing test showed that 9% acetic acid water solution (AAWS) and BV had strong protective efficacy against Aedes albopictus. The limb skin landing test also showed that BV and AAWS had protective efficacy. The sugar-feeding behavioral bioassay showed that mosquitoes were repelled by the smell of AAWS. There was no significant difference between the number of mosquitoes that landed on the two Petri dishes treated with BV (6.6% acetic acid (AA)), 4.5% AAWS, 9% AAWS, and 4.5% DEET, but a significant difference was found among BV (6.6% AA), 4.5% AAWS, 9.0% AAWS, DEET, and distilled water. The arm-in-cage tests showed that there was a descending order for the duration of complete protection was DEET (75-90 min) = BV (75-90 min) > formic acid (60-75 min) > AA (45-60 min) > propanoic acid (30-45 min) > butanoic acid (15-30 min) > water (0 min). The safety tests showed that the acute oral toxicity (LD50) of BV (6.6% AA) was > 5000 mg/kg for mice and produced no red spots or edema symptoms. Furthermore, the dermal sensitization rate was zero for rabbits, and the marrow micronucleus rates for mice were negative. In summary, BV can be safely used for volatilization and skin applications.