Fire Ants Strike a Good Note
1
ψ ι e n : *.:-*.- _ ^„ in fir»e ant venom antibiotic and insecticide BANE or BLESSING? Venom from the fire ant shows strong antibiotic activity i HE HE is some good in everything—ap- parently even in fire ants. Researchers at Loaiisiariici State University set out to find 'M way to eliminate the fire ant (a multiirnillion dollar project in eight southern srtates) and learned that the ant's A'enorsi shows strong antibiotic ac- tivity against several bacteria and molds. Most antibiotics now available comb»ateitlier bacteria or molds, seldom both, says I^SU's Murray Blum. Tine venom, says Blum, is also a very potent insecticide; no known insect is immune t o it. It acts much like a tran- quilizer. "While other insecticides make insects nervous and jittery, fire ant venoirn makes triem calm. But exactly how it attacks trie nervous system is un- known so far. THe venom is highly toxic to the fruitfly, housefly, termite, boll weevil, and rice weevil. Even two species of mites are riiglily susceptible to it, though most conimeicial insecticides don't kill mites. TTie lire ant itself, though, is not very sensitive to its own venom whesi it is "painted on." S o far, the exact chemical nature of the 'venom is a mystery. But if it can be synthesized, says Blum, it will pro- duce? a very effective insecticide. In- sects shoijild not become immune to a substance produced by themselves, he adds. Tliougln the LSU scientists know ther«e is an antibiotic present in the venom, trney still have to isolate it and test its activity in the human body. It's poss-ible, says Arthur F. Novak, direc- tor of the antibiotic research, that the fire ants poison itself may be antibiotic, a general protoplasmic poison which is nonselective and multipurpose. In tests, the venom has proved effec- tive against ^Micrococcus pyt9gvtn'\. Streptococcus pyogenes. Escherichia coli, Lactobacillus crt.se/, and a variety of molds. The venom's antibiotic activity probably explains why pustules arising at the site of sting are antiseptic. E. O. Wilson of Harvard University finds that the fire ant lays a trail with its venom which othei ants follow. If a man-made trail is laid, the ants will also follow that. This may pa\e the \\.i\ to selectively destroying the ant. Insecti- cide traps could be laid, and the ant led to them by trails of its own venom. This probably woidd not attract other insects, and it is unlikely that the ant would become resistant to its own trail- lay ing substance. In the long run, says Blum, it may be possible to practice in- sect control by using material which the ants themselves produce without harm- ing beneficial insects. • Properties Pinpointed. Though the venom's composition hasn't yet been unraveled, a lot is known about tlie ma- terial. The venom is soluble in most organic solvents, «and is insoluble in and less dense than water, in which it dis- perses as fine, milk-colored globules. It is also non-proteolytic The venom lias fwrm phases—an alkaline carrier and dro'pleb», wiiivrii «uc lie·»vie-Γ than îJuC «ΜΓΒΠΡΓ. The researchers find onî v ' :*îînhiitie C!-H chains; tfiis shows thiit the veiaom is nonaromatie. It contains both methyl and methylene groups*, a possible ether linkage, and a carbony! gr>up which rlop^s nr>r appear to be an ope*n chain, simple ketone. The C-H C = 0 ratio is much higher when the sample contains small amounts of suspended globules. This indicates tliit-t the globular component contributes niosst or all of tîie carbonyi-con tain ing compound. ^Ants Milked. The LSU research tcAin gets its venom samples by "uiilk- inpr" the ants, teasing them with a glass capillary into \\Tiich poison is ejected- Tlaey collect ants by picking up an ant hill with a postriole digger ^»d putting it in a garbage can filled with water. Tlie dirt sinks and the ants, clinging to- gether, float to trie top. Then the scien- tists collect them in clusters. One member of th~ research group^ J amies G. Trayfiam, is working on a faster and less painful way to get the venom. The ants are killed by deep- freezing, then stirred with water in a blender. This makes a thick soup, wtiich is then steam-distilled. Tra\ ham then mixes the distillant with ether to separate it from water. ANT SOUP. LSU's J. G. Trayham adds fnozen ants to a blender as first step to recover venomous products. Ants are then* mixed with water and steam-distilled MARCH 3 0, 1959 C&EN 35 New Text Fire Ants Strike a Good Note
Transcript of Fire Ants Strike a Good Note
ψ
ι e n : *.:-*.- _ ^„
i n fir»e ant venom antibiotic and insecticide
BANE or BLESSING? Venom from the fire a n t shows strong antibiotic activity
i H E HE is some good in everything—apparently e v e n in fire ants . Researchers at Loaiisiariici State University set out to find 'M way to eliminate the fire ant (a multiirnillion dollar project in eight southern srtates) and learned that the ant's A'enorsi shows strong antibiotic activity against several bacteria and molds. M o s t antibiotics now available comb»ateitlier bacteria or molds, seldom both, says I^SU's Murray Blum.
Tine venom, says Blum, is also a very potent insecticide; no known insect is immune t o it. I t acts much like a tranquilizer. "While other insecticides make insects nervous and jittery, fire ant venoirn makes triem calm. But exactly how it attacks tr ie nervous system is un-known so far.
THe venom is highly toxic to the fruitfly, housefly, termite, boll weevil, and rice weevil. Even two species of mites are riiglily susceptible to it, though most conimeicial insecticides don't kill mites . TTie l ire ant itself, though, is not very sensitive to its own venom whesi it is "painted on."
S o far, the exact chemical na ture of the 'venom is a mystery. But if it can be synthesized, says Blum, it will produce? a v e r y effective insecticide. Insects shoijild n o t become immune to a substance produced by themselves, h e a d d s .
Tliougln the LSU scientists know ther«e is an antibiotic present in the venom, trney still have t o isolate it and test its activity in the human body. It's poss-ible, says Arthur F . Novak, direc
tor of the antibiotic research, that the fire a n t s poison itself may be antibiotic, a general protoplasmic poison which is nonselective and multipurpose.
In tests, the venom has proved effective against ^Micrococcus pyt9gvtn'\. Streptococcus pyogenes. Escherichia coli, Lactobacillus crt.se/, and a variety of molds. The venom's antibiotic activity probably explains why pustules arising at the site of sting are antiseptic.
E. O. Wilson of Harvard University finds that the fire ant lays a trail with its venom which othei ants follow. If a man-made trail is laid, the ants will also follow that. This may pa \e the \\.i\ to selectively destroying the ant. Insecticide traps could be laid, and the ant led to them b y trails of its own venom. This probably woidd not attract other insects, and it is unlikely that the ant would become resistant to its own trail-lay ing substance. In the long run, says Blum, it may be possible to practice insect control by using material which the ants themselves produce without harming beneficial insects.
• Proper t ies Pinpointed. Though the venom's composition hasn't yet been
unraveled, a lot is known about tlie material. The venom is soluble i n most organic solvents, «and is insoluble in and less dense than wate r , in which it disperses a s fine, milk-colored globules. It is also non-proteolyt ic T h e venom lias fwrm phases—an alkaline carrier and dro'pleb», wiiivrii «uc lie·»vie-Γ than îJuC «ΜΓΒΠΡΓ.
The researchers find onîv ' :*îînhiitie C!-H chains; tfiis shows thiit the veiaom is nonaromatie. It contains both methyl and methylene groups*, a possible ether linkage, and a carbony! gr>up which rlop^s nr>r appear t o be an ope*n chain, s imple ketone.
The C-H C = 0 ratio is much higher when the sample contains small amounts of suspended globules. This indicates tliit-t the globular component contributes niosst or all of t î ie carbonyi-con tain ing compound.
^ A n t s Milked. The LSU research tcAin gets its venom samples by "uiilk-inpr" the ants, teasing them with a glass capillary into \\Tiich poison is ejected-Tlaey collect ants by picking u p an ant hill with a postriole digger ^»d putting it in a garbage can filled with water. Tlie dirt sinks and the ants , clinging together, float to trie top. Then t h e scientists collect t hem in clusters.
One member of th~ research group^ J amies G. Trayfiam, is working o n a faster and less painful way to get the venom. T h e ants are killed b y d e e p freezing, then stirred with water in a blender. This makes a thick soup , wtiich is then steam-distilled. Tra\ h a m then mixes the distillant with e ther t o separate it from water.
ANT SOUP. LSU's J. G. Trayham adds fnozen ants to a blender as first step t o recover venomous products . Ants are then* mixed with w a t e r and steam-distilled
M A R C H 3 0, 1 9 5 9 C & E N 3 5
New TextFire Ants Strike a Good Note
