title: Application of microalgal fucoxanthin for the reduction of colon cancer risk: inhibitory activity of fucoxanthin against beta-glucuronidase and DLD-1 cancer cells.
abstract: Intestinal bacterial beta-glucuronidases are capable of retoxifying compounds that have been detoxified by liver glucuronidation and are also known to accelerate colon cancer invasion and metastasis. In this study, fucoxanthin extracted from the microalga Phaeodactylum tricornutum was investigated for its inhibitory activity against Escherichia coli beta-glucuronidase and DLD-1 cancer cells. Fucoxanthin inhibited beta-glucuronidase in a concentration-dependent manner with an IC50 value of 2.32 mM and a mixed inhibition type. Fucoxanthin had more potent inhibitory activity on beta-glucuronidase at 37 degrees C and in alkaline conditions. Fucoxanthin also inhibited the beta-glucuronidase activity of DLD-1 cancer cells at a concentration of 20-50 microM. The presence of beta-glucuronidase and substrate in the medium decreased the inhibitory activity of fucoxanthin against DLD-1 cancer cells. Therefore, microalgal fucoxanthin might prevent colon cancer because of its strong beta-glucuronidase inhibitory activity and could be utilized as a novel functional ingredient of food and pharmaceutical supplements.
authors.forename: Arthitaya
authors.initials: A
authors.lastname: Kawee-Ai
authors.forename: Sang Moo
authors.initials: SM
authors.lastname: Kim
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000188:drug therapy*; D005966:Glucuronidase / Q000037:antagonists & inhibitors*; D006801:Humans; D058086:Microalgae / Q000737:chemistry*; D024341:Xanthophylls / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D024341:Xanthophylls; C025164:fucoxanthin; D005966:Glucuronidase