ORIGINAL ARTICLE Reduction of aflatoxin level in aflatoxin-induced rats by the activity of probiotic Lactobacillus casei strain Shirota E. Nikbakht Nasrabadi 1 , R. Jamaluddin 1 , M.S. Abdul Mutalib 1 , H. Khaza’ai 2 , S. Khalesi 1 and S. Mohd Redzwan 1 1 Department of Nutrition and Dietetics,Faculty of Medicine and Health Sciences,Universiti Putra Malaysia,Selangor, Malaysia 2 Departments of Biomedical Sciences,Faculty of Medicine and Health Sciences,Universiti Putra Malaysia,Selangor, Malaysia Keywords aflatoxin B 1 , chronic aflatoxicosis, probiotic Lactobacillus casei Shirota. Correspondence Rosita Jamaluddin, Department of Nutrition and Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia. E-mail: rosi- ta@medic.upm.edu.my 2013/2084: received 22 November 2012, revised 17 January 2013 and accepted 17 January 2013 doi:10.1111/jam.12148 Abstract Aims: Aflatoxin B 1 (AFB 1 ) is considered as the most toxic food contaminant, and microorganisms, especially bacteria, have been studied for their potential to reduce the bioavailability of mycotoxins including aflatoxins. Therefore, this research investigated the efficacy of oral administration of Lactobacillus casei Shirota (LcS) in aflatoxin-induced rats. Methods and Results: Sprague Dawley rats were divided into three groups of untreated control, the group induced with AFB 1 only, and the group given probiotic in addition to AFB 1 . In the group induced with AFB 1 only, food intake and body weight were reduced significantly. The liver and kidney enzymes were significantly enhanced in both groups induced with AFB 1 , but they were lower in the group given LcS. AFB 1 was detected from all serum samples except for untreated control group’s samples. Blood serum level of AFB 1 in the group induced with AFB 1 only was significantly higher than the group which received probiotic as a treatment (P < 005), and there was no significant difference between the control group and the group treated with probiotic. Conclusions: LcS supplementation could improve the adverse effect of AFB 1 induction on rats’ body weight, plasma biochemical parameters and also could reduce the level of AFB 1 in blood serum. Significance and Impact of the Study: This study’s outcomes contribute to better understanding of the potential of probiotic to reduce the bioavailability ofAFB 1 . Moreover, it can open an opportunity for future investigations to study the efficacy of oral supplementation of probiotic LcS in reducing aflatoxin level in human. Introduction Toxins are regularly ingested. A number of toxins come from foods eaten every day. As one of the main groups of toxicants that naturally occur in food, mycotoxins are said to pose a considerable health risk (Shetty and Jesper- sen 2006). The most important mycotoxin is aflatoxin (Pitt 2000). Aflatoxin is a fungal toxin and commonly found to contaminate a variety of food commodities such as maize and other types of crop especially during the process of production, harvesting, storage or processing (Logrieco et al. 2003). It can often be found in staple food, including groundnuts and oil seeds, like maize. Aspergillus flavus and Aspergillus parasiticus, which are both from Aspergillus species of fungi and are both classi- fied as group one carcinogen by the International Agency for Research on Cancer (IARC), can produce aflatoxin B 1 (AFB 1 ). The exposure to aflatoxin is linked to chronic disease such as liver cancer. Among many aflatoxin metabolites, AFB 1 is a very strong carcinogen in many Journal of Applied Microbiology 114, 1507--1515 © 2013 The Society for Applied Microbiology 1507 Journal of Applied Microbiology ISSN 1364-5072