The plant compound tryptanthrin reduces the food poisoning bacteria Campylobacter in the chicken gut at low concentration

Updated:November 10, 2023 (Friday)

-Towards the development of chicken feed that controls Campylobacter infection-

Food poisoning due to Campylobacter, with chicken meat as main causative food, has become a major issue. It is thought that the chicken meat gets contaminated by the existence of large amounts of Campylobacter in the intestinal tract of infected chickens, and the contamination of edible parts during the poultry processing. The National Agriculture and Food Research Organization (NARO) has revealed for the first time that the plant compound tryptanthrin is effective in reducing the number of Campylobacter in the chicken intestinal tract, even at low concentrations. It is expected that the development of plant-based feed using tryptanthrin will lead to a significant reduction in food poisoning caused by Campylobacter.


The main food that causes food poisoning via Campylobacter is raw or undercooked chicken meat. Chickens infected with Campylobacter are often asymptomatic, but their intestines harbor significant bacterial loads. It is thought that contamination spreads in the food chain due to infection to other chickens through feces, contamination of intestinal content with edible parts and cross-contamination during poultry processing. Therefore, there is a need to develop technologies and materials that can reduce the amount of Campylobacter in the chicken intestinal tract to produce safe and secure chicken meat.

NARO has revealed for the first time that tryptanthrin, a type of plant alkaloid found in high concentrations in plants such as indigo, exhibits antibacterial activity at low concentrations against Campylobacter, which causes food poisoning. It was found that tryptanthrin has a stronger antibacterial effect on Campylobacter than other plant compounds that have been reported so far, and it significantly reduced the number of bacteria in the chicken intestinal tract even when administered at low concentrations in drinking water. Also, no negative effects on chicken weight gain were confirmed.

In the current poultry industry, feed products that focus on the various functionalities of herbs and other plant-based ingredients are widely used for the improvement of health and productivity of chickens, as well as the taste and safety of chicken and eggs. In the future, it is expected that the development of plant-based feed and veterinary drugs that uses tryptanthrin to control Campylobacter infection in chickens, will lead to a significant reduction in the occurrence of food poisoning due to Campylobacter.


Tryptanthrin reduces Campylobacter jejuni colonization in the chicken gut by a bactericidal mechanism. Iwata T, Watanabe-Yanai A, Tamamura-Andoh Y, Arai N, Akiba M and Kusumoto M. Applied and Environmental Microbiology DOI:

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