FULL COMMUNICATION Identification and Characterization of Phytohemagglutinins from White Kidney Beans (Phaseolus vulgaris L., var. Beldia) in the Rat Small Intestine Nader Nciri, 1–3 Namjun Cho, 3 Faic ¸al El Mhamdi, 1 Abderraouf Ben Mansour, 1 Fayc ¸al Haj Sassi, 1 and Fatma Ben Aissa-Fennira 1 1 Intestinal Immunophysiology-Research Unit (02/RU/09-02), Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia. 2 Department of Animal Resources, Fisheries, and Food Technology, National Institute of Agronomy of Tunisia, Tunis, Tunisia. 3 School of Energy, Materials, and Chemical Engineering, Korea University of Technology and Education, Cheonan, Chungnam, Korea. ABSTRACT Although kidney bean (Phaseolus vulgaris L.) lectin toxicity is widely known, its effects in the gastrointestinal tract require further study. This investigation aimed to identify and characterize phytohemagglutinins (PHAs) in the small intestine and sera of rats following oral challenge with ground white beans. Twenty young, adult male rats were divided randomly into two groups of 10 animals each. The control group underwent gavage with a suspension of 300 mg of rodent pellet flour. The experimental group was administered a 300 mg Beldia bean flour suspension (BBFS). After 10 days of daily treatment, jejunal rinse liquid ( JRL) and ileum rinse liquid and secretions, as well as sera, were collected. All biological fluids were screened for lectin reactivity using competitive inhibition ELISA, Ouchterlony double immunodiffusion, and immu- noelectrophoresis techniques. The results revealed the presence of immunogenic intraluminal PHAs 3–4 h after the oral intake of the BBFS in the JRLs as well as in the jejunal and ileal secretions; however, no PHA was detectable in the rat sera. Ingestion of raw Beldia beans may lead to interaction between PHAs and the mucosa of the small intestine, potentially resulting in an inflammatory response. KEY WORDS:  ileum  jejunum  Phaseolus vulgaris L.  phytohemagglutinins  white kidney beans INTRODUCTION P haseolus vulgaris L. beans contain various anti- nutritional factors (ANFs). 1 The main ANFs in these beans are lectins, trypsin inhibitors, and, in the colored flowering varieties, tannins. It is well established that the lectins in P. vulgaris are highly toxic and are the main factors responsible for the negative effects that manifest following ingestion by livestock or humans. 2–4 P. vulgaris lectins, also referred to as phytohemaggluti- nins (PHAs), are carbohydrate-binding glycoproteins found in many species of beans. One of the striking biological features of PHAs is their ability to survive digestion in the alimentary canal of consumers. This feature allows PHAs to bind to the glycosylated membrane of the cells that line the digestive tract. 5–7 This interaction triggers a cascade of detrimental local and systemic reactions, making this class of molecules antinutritional and/or toxic. Locally, they ad- versely influence the turnover and loss of gut epithelial cells, damage the epithelial lumen, and impede digestion and absorption processes. 8,9 Systemically, they disturb protein, carbohydrate, and lipid metabolism, 10–12 promote enlarge- ment and/or atrophy of key internal organs and tissues, and cause altered hormonal and immunological status. 13,14 At high intake amounts, PHAs can gravely threaten the growth and health of the animal or human who consumes them. 2–4 The fact that PHAs are so widely distributed in food items that are commonly consumed by humans raises the impor- tant question of whether they pose any significant risk to human health. Fortunately, most PHAs are easily destroyed by the traditional methods of household cooking. Never- theless, under special conditions, complete detoxification may not always be achieved, especially if ground seeds are used or industrial processes for quick cooking are applied. Because PHAs are resistant to inactivation by dry heat, 15 practices such as the use of raw bean flours in baked goods should be viewed with caution. The presence of nutritionally significant amounts of ac- tive PHAs in fresh and processed foods and the lack of public knowledge concerning the deleterious effects of di- etary lectins on the gut and general health have led to several cases of human intoxication. For example, an outbreak of what appeared to be food poisoning occurred in England in 1976. A party of school- boys on holiday ate kidney beans that had been soaked in Manuscript received 19 December 2014. Revision accepted 19 September 2015. Address correspondence to: Nader Nciri, PhD, Intestinal Immunophysiology-Research Unit (02/RU/09-02), Faculty of Medicine of Tunis, University of Tunis El Manar, 15, Street Djebel Akhdhar, Bab Saaˆdoun 1007, Tunis, Tunisia. E-mail: nciri_nader@yahoo.fr JOURNAL OF MEDICINAL FOOD J Med Food 00 (0) 2015, 1–13 # Mary Ann Liebert, Inc., and Korean Society of Food Science and Nutrition DOI: 10.1089/jmf.2014.0194 1