Search

Alexandre-Léon Étard (1852-1919) was a French chemist who studied alkaloids in general and nicotine in particular. Together with Cahours he investigated the reaction of nicotine with sulfur, synthesized tetrapyridine and studied its reaction with a variety of reagents. The results indicated that nicotine could be considered a combination of bipyridine and hydrogen, which upon reaction with sulfur transformed into tetrapyridine and thiotetrapyridine. The latter reacted with nitric acid yielding isobipyridine. The reaction with selenium and other reagents led to the formation of hydrocollidine and isopyridin, and the proposal of the possible formula of pyridine. Étard also studied the phenomenon of putrefaction and hydrolysis of tissues. He found that the release of nitrogen signaled the beginning of putrefaction, accompanied by the replacement of large bacilli by smaller ones. In the absence of air, putrefaction split the albumen molecule and proceeded by simple hydration. He studied in detail the substances that accompanied the chlorophyll present in vegetables and concluded that the green matter present in leaves contained a fundamental nucleus, very stable, that carried the function of optical absorption connected to the biological work. To this nucleus different chemical groups could be attached, giving place to chlorophylls that differed in their composition, molecular mass, isomerism etc. and the role they played in living plants. Étard and Vila separated a benzoyl derivative from the products of the hydrolysis of tissues and claimed that it was the cause of the many accidents that occurred during the eating of muscles. [ABSTRACT FROM AUTHOR]

The betel nut or areca nut is the seed of the palm tree of bétele (areca catechu), one of the most popular plants of the world. Asians, by cultural influence, have the custom of chew the seed of this sort of vegetable. Between its active principles: arecaine and arecoline, they are alkaloids comparable to the nicotine in the neural stimulation effects. The active substance causes a pleasant relaxion sensation in the mouth, sensation that is extended to the central nervous system. However, chewing regularly betel nut dryes of red the saliva and blackens the teeth being extremely harmful to the mouth health causing early the loss of the teeth. Despite of the harmful effects, the difficulty to eliminate this habit is due to its deep cultural character. Chewing bétel nuts and have the teeth stained it's a motive of proud. The International Agency of Research of the Cancer (IARC) classifies the bétel nut as carcinogenic acquaintance, and the literature have many studies that relate this custom with the oral cancer. The study has as goal to do a critical analysis of the utilization of this substance, searching to inform to the community their bad effects. [ABSTRACT FROM AUTHOR]