Cytotoxicity of Bulgarian spring water probiotics (probiotic Laktera Nature®) on colon carcinoma cell line


Colorectal carcinoma is a malignant disease, from which more than 1 million people worldwide suffer. Over the past two decades, its social significance attracts more attention. Colorectal cancer is the second leading cause of death from malignancy and the third most frequently diagnosed malignancy. It has been estimated that nutrition is the main reason for the high incidence of cancer. Probiotics are live microorganismswith proven health benefits in a variety of gastrointestinal diseases, and disorders outside the gastrointestinal tract. In this study, we wanted to explore cytotoxicity and anti-proliferative activity of the new probiotic Laktera Nature® on non-cancerous cell lines – 3T3 and BJ and colon adenocarcinoma cell line – HT-29. Probiotic Laktera Nature® has weak direct cytotoxicity against 3T3 and BJ cells, but inhibits their proliferation in a dose-dependent manner. On carcinoma cell line – HT-29, in low concentration range (2-125 µg/ml) probiotic Laktera Nature® stimulates proliferation; at high concentrations (250-1000 µg/ml) we detected concentration-dependent inhibition of proliferation. Probiotic Laktera Nature® has shown promising primary screening results, which should be clarified as mechanisms in further works.

Kaloyan Georgiev – Department of Preclinical and Clinical Sciences, Sector Pharmacology and Toxicology, Faculty of Pharmacy, Medical University Varna, Marin Drinov str. 55, 9002 Varna, Bulgaria. Correspondence to Dr. KaloyanGeorgiev, Department of Preclinical and Clinical Sciences, Sector Pharmacology and Toxicology, Medical University, Marin Drinov 55, 9002 Varna, Bulgaria. Phone: +359898343274, E-mail:

Marieta Georgieva – Institute of Experimental Morphology, Pathology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria

Maria Peneva – Medical Centre “Evrozdrave” Sofia, Sofia, Bulgaria

Georgi Alexandrov – Military Medical Institute Academy – Sofia, Sofia, Bulgaria