Garlic beats antibiotics in quelling food-borne illness

Researchers have isolated a compound in garlic that is a 100 times more potent than popular antibiotics in combating Campylobacter bacteria, one of the commonest causes of intestinal illness. Some 2.4 million Americans alone are affected by Campylobacter every year, according to the Centers for Disease Control and Prevention, with symptoms including diarrhoea, cramping, abdominal pain and fever. “This work is very exciting to me because it shows that this compound (diallyl sulphide) has the potential to reduce disease-causing bacteria in the environment and in our food supply,” says Xiaonan Lu, postdoctoral researcher at the Washington State University, who led the study. Lu and colleagues looked at the ability of the garlic compound, diallyl sulphide, to kill the bacteria when it is protected by a slimy biofilm that makes it 1,000 times more resistant to antibiotics, the Journal of Antimicrobial Chemotherapy reports. They found the compound can easily penetrate the protective biofilm and kill bacterial cells by combining with a sulphur-containing enzyme, changing the enzyme’s function and effectively shutting down cell metabolism, according to a Washington statement. The researchers found that diallyl sulphide was as much as 100 times effective than much of the antibiotics erythromycin and ciprofloxacin and would often work in a fraction of the time. “This is the first step in developing or thinking about new intervention strategies. Campylobacter is simply the most common bacterial cause of food-borne illness in the United States and probably the world,” says Michael Konkel, study co-author who has been researching Campylobacter jejuni for 25 years. Previously, Lu and colleagues found that diallyl sulphide effectively kills important foodborne pathogens, such as listeria monocytogenes and Escherichia coli O157:H7.