by April McCarthy
A significant finding from Washington State University shows that garlic is 100 times more effective than two popular antibiotics at fighting disease causing bacteria commonly responsible for foodborne illness.
Their work was published recently in the Journal of Antimicrobial Chemotherapy a follow-up to the author's previous research in Applied and Environmental Microbiology which conclusively demonstrated that garlic concentrate was effective in inhibiting the growth of C. jejuni bacteria.
Garlic is probably nature's most potent food. It is one of the reasons people who eat the Mediterranean diet live such long healthy lives. Garlic is also a powerful performer in the research lab.
"This work is very exciting to me because it shows that this compound has the potential to reduce disease-causing bacteria in the environment and in our food supply," said Xiaonan Lu, a postdoctoral researcher and lead author of the paper.
One of the most interesting of the recent findings is that garlic increases the overall antioxidant levels of the body.
Scientifically known as Allium sativa, garlic has been famous throughout history for its ability to fight off viruses and bacteria. Louis Pasteur noted in 1858 that bacteria died when they were doused with garlic. From the Middle Ages on, garlic has been used to treat wounds, being ground or sliced and applied directly to wounds to inhibit the spread of infection. The Russians refer to garlic as Russian penicillin.
"This is the first step in developing or thinking about new intervention strategies," saif Michael Konkel, a co-author who has been researching Campylobacter jejuni for 25 years.
"Campylobacter is simply the most common bacterial cause of food-borne illness in the United States and probably the world," Konkel said. Some 2.4 million Americans are affected every year, according to the U.S. Centers for Disease Control and Prevention, with symptoms including diarrhea, cramping, abdominal pain and fever.
The bacteria also are responsible for triggering nearly one-third of the cases of a rare paralyzing disorder known as Guillain-Barre syndrome.
Diallyl disulfide is an organosulfur compound derived from garlic and a few other genus Allium plants. It is produced during the decomposition of allicin, which is released upon crushing garlic
Lu and his colleagues looked at the ability of diallyl sulfide to kill the bacterium when it is protected by a slimy biofilm that makes it 1,000 times more resistant to antibiotics than the free floating bacterial cell. They found the compound can easily penetrate the protective biofilm and kill bacterial cells by combining with a sulfur-containing enzyme, subsequently changing the enzyme's function and effectively shutting down cell metabolism.
The researchers found the diallyl sulfide was as effective as 100 times as much of the antibiotics erythromycin and ciprofloxacin and often would work in a fraction of the time.
Two previous works published last year by Lu and WSU colleagues in Applied and Environmental Microbiology and Analytical Chemistry found diallyl sulfide and other organosulfur compounds effectively kill important food-borne pathogens, such as Listeria monocytogenes and Escherichia coli O157:H7.
"Diallyl sulfide may be useful in reducing the levels of the Campylobacterin the environment and to clean industrial food processing equipment, as the bacterium is found in a biofilm in both settings," Konkel said.
"Diallyl sulfide could make many foods safer to eat," said Barbara Rasco, a co-author on all three recent papers and Lu's advisor for his doctorate in food science. "It can be used to clean food preparation surfaces and as a preservative in packaged foods like potato and pasta salads, coleslaw and deli meats."
"This would not only extend shelf life but it would also reduce the growth of potentially bad bacteria," she said.
The natural substance could also be derived without artificially introducing harmful chemicals to disruptive its disease-reducing abilities.
Ironically, many researchers think that antibiotics may be just one of several factors that contribute to intestinal blockage in young children.