This is a photomicrograph of Clostridium botulinum bacteria. A possible antitode to botulism, considered the most poisonous proteins known to mankind, have been itentified. Image courtesy Centers for Disease Control and Prevention

Nov. 5 (UPI) -- Researchers have identified a possible antidote to botulism, which is considered the most poisonous compound known to mankind.

The new compound , nitrophenyl psoralen, can reduce paralysis induced by botulinum neurotoxin, which is considered a potential bioweapon because there is no antidote approved for use by the U.S. Food and Drug Administration. The findings were published last week in the journal Environmental Microbiology.


There are fewer than 200 botulism cases worldwide annually.

"These cost more to treat than the millions of salmonella outbreaks that occur, making botulism the most expensive form of food poisoning," corresponding author Dr. Bal Ram Singh, a professor and director of the Botulinum Research Center at Dartmouth, said in An American Society for Microbiology press release.

Botulism can be acquired by food poisoning, from soil or through other methods such as wound contamination and colonization of the digestive tracts of children and infants.

The toxin is produced by Clostridium botulinum, which is hard to kill -- spores can even survive being boiled.

For the new finding, researchers screened 300 small natural compounds and their analogues extracted from Indian plants against botulinum neurotoxins.

The researchers then tested NPP's activity in vitro, as well as in cell culture, against botulinum neurotoxin type A -- the most potent serotype among the seven serotypes of botulinum toxin.

NPP type A possessed powerful anti-botulinum toxin activity and low toxicity to human cells.

In addition, NPP reversed muscle paralysis in mice induced by botulinum neurotoxin type A.

Because psoralen-derived drugs have already been approved by FDA, Singh expects a quick approval process for NPP.

The study on botulism was an outgrowth of work on biochemical basis of Ayurveda, an herbal medicine system widely used in India. Natural products have more diversified structures, lower toxicity and better drug-like properties than synthetics, the researchers noted.