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"Arachnicillin" by: Vicki L. Glembocki (Research/Penn State,
Vol. 16, no. 3 (September, 1995))
An advertisement a few years ago in Parade Magazine caught the
attention of Penn State biologist Don McKinstry: "Learn how a
cobweb can help you when you get a cut in the woods."
Medical folklore, he wondered, akin to rubbing butter on a
burn? Or a bona fide folk remedy?
Spider webs have been used for wound dressings since the
first century A.D. -- perhaps because spiders were thought to be
"lucky," McKinstry says. The custom remained popular through
Shakespeare's day: "I shall desire you of more acquaintance, good
master cobweb," said the character Bottom in A Midsummer Night's
Dream. "If I cut my finger, I shall make bold of you."
Not so today. Out of 100 biology students surveyed at Penn
State Erie--The Behrend College, only 10 had ever heard of using
spider webs on cuts. One had actually tried this remedy . . .
reportedly, with success.
Yet most people, given the choice, opt for a glob of
Neosporin and a Band-Aid. They're inexpensive. They're effective.
They involve no creepy crawlies.
Neosporin may not always do the trick, asserts one of
McKinstry's biology students, Lori Springer. "Different strains
of bacteria are becoming resistant to the antibiotics we have
now," she explains, "so there's been a drive in recent years to
find natural sources of antibiotics -- new ones."
It's not the webs themselves that supposedly protect against
microbial attack. It's a chemical coating on the silk, much like
the sticky coating for prey capture, which is released from one
of many glands as the spider spins the web. Arachnologist Rainer
Foelix notes in his book, Biologie der Spinnen, that the coating
may protect old and abandoned webs from fungal and bacterial
attack.
"This antiseptic quality of the spider web," writes Foelix'
colleague Fritz Vollrath in Scientific American, "may account for
its renown as a folk remedy for dressing wounds."
In spite of the literary and scientific references to spider
web remedies, no clinical or laboratory studies on the subject
have yet been documented. Springer has found research on the
structure of spider webs, on their geometry, on the way they
capture prey, on spider biology, on superstitions and folklore.
But she has found nothing that examines the antimicrobial effects
of the webs.
Currently she is testing for such effects in known spider
web chemicals -- choline, betaine, isethionic acid, lysine, and
cysteic acid. She takes a small paper disk, like the cut-out from
a paper punch, saturates it with one of the chemicals, and places
it in a petri dish that contains a bacterial strain -- one of the
four reference strains routinely used for antibiotic testing.
(The most common is Escherichia coli or E. coli, a human
intestinal bacterium often the cause of water pollution.) If the
only change in the dish after an 18-hour incubation period is
bacteria growth, the chemical has had no effect. But if there is
a sizable clear zone around the disk, the chemical has
successfully inhibited the growth of the bacteria and is,
therefore, antimicrobial. So far, Springer has had only marginal
success with one of the chemicals.
But Springer's test chemicals were extracted from the webs
of fairly few species of spider. The chemical she's looking for
may not be on those particular webs from those particular
spiders: It may be on webs spun by other spiders, of which there
are more than 35,000 species worldwide. Springer is starting
small. ("The truth is," she admits, "I'm not too crazy about
spiders.") She's planning to collect spiders -- around 50 in all
-- from Presque Isle State Park on Lake Erie and from the Behrend
College campus. Each will be housed in its own glass box where
each will spin its own web -- all stored (sans tuffet, curds, and
whey) in Springer's tiny basement lab at Behrend. She will
harvest the webs, soak them in solvents, and then test the
chemicals left in the resulting solutions, using the same disk-procedure as before.
"They've found antibiotics in sharks and in frogs," she
says. "Spider webs could be another source."
Lori Springer is an undergraduate student in biology. Don
McKinstry, Ph.D., is associate professor of biology, Penn State
Erie--The Behrend College, Station Road, Erie, PA 16563; 814-898-6402.
Springer's research is funded by an undergraduate student
research grant from The Behrend College.
Vicki L. Glembocki is a former writing R/PS intern and current
associate editor at Pitt Magazine.
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