Thirteen-week oral dose toxicity study of Oligonol containing oligomerized polyphenols extracted from lychee and green tea

• Published in: Regulatory toxicology and pharmacology 2014-02, Vol.68 (1), p.140-146
• Main Authors: Kitadate, Kentaro, Homma, Kohei, Roberts, Ashley, Maeda, Takahiro
• Format: Article
• Language: English
• Subjects: Animals; Camellia sinensis; Catechin; Catechin - analogs & derivatives; Catechin - toxicity; Female; Fruit; Litchi; Low molecular polyphenols; Male; Nasal cavity; Nasal Cavity - anatomy & histology; Nasal Cavity - drug effects; No-Observed-Adverse-Effect Level; Oligonol; Phenols - toxicity; Plant Extracts - chemistry; Rats; Rats, Sprague-Dawley; Toxicity Tests, Subchronic; Toxicology
• ISSN: 0273-2300; 1096-0295
• DOI: 10.1016/j.yrtph.2013.12.001

•The safety of Oligonol was confirmed by 13-week repeated oral dose toxicity study in rat.•It was confirmed that Oligonol has no subchronic toxicity.•The nasal cavity was not affected by Olignol administration.•It was shown that Oligonol is a safety ingredient at recommended dose. Oligonol is a functional food containing catechin-type monomers and proanthocyanidin oligomer converted from polymer forms via a novel manufacturing process. The catechin component of green tea extract has been associated with nasal toxicity in rats following subchronic exposure. To assess the potential for Oligonol to induce nasal toxicity a 13-week repeated oral dose toxicity study was conducted in rats using doses of 100, 300, and 1000mg/kg/d. Clinical signs and mortality were not affected by Oligonol treatment. Compound-colored stools and an increase in food consumption were observed in some treated groups; however, there were no treatment-related differences in terminal body weights or with respect to the results of the gross postmortem examinations. Histopathological evaluation of the nasal cavity tissues revealed no treatment-related lesions. The results from this toxicity study indicate that Oligonol does not induce nasal toxicity and further supports the results of previous studies demonstrating the safety of Oligonol for human consumption.