Bamboo pyroligneous acid as a novel insecticide, its mosquito repellency activity, chemical components and safety towards animals was written by Li, Zhikun;Maliang, Huidong;Liu, Qing;Chen, Anliang;Liu, Hongbo;Lin, Haiping;Ma, Jianyi;Wang, Pinwewi. And the article was included in Fresenius Environmental Bulletin in 2022.Reference of 626-64-2 This article mentions the following:
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% DEBT, but a significant difference was found among BV (6.6% AA), 4.5% AAWS, 9.0% AAWS, DEBT, and distilled water. The arm-in-cage tests showed that there was a descending order for the duration of complete protection was DEBT (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 neg. In summary, BV can be safely used for volatilization and skin applications. In the experiment, the researchers used many compounds, for example, Pyridin-4-ol (cas: 626-64-2Reference of 626-64-2).
Pyridin-4-ol (cas: 626-64-2) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Reference of 626-64-2