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

Regul Toxicol Pharmacol. 2014 Feb;68(1):140-6. doi: 10.1016/j.yrtph.2013.12.001. Epub 2013 Dec 8.

Abstract

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 1000 mg/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.

Keywords: ANOVA; Catechin; EGCG; GTE; H&E; Hematoxylin & Eosin; IACUC; Institutional Animal Care and Use Committees; LD(50); LFP; LOAEL; Low molecular polyphenols; MOS; NOAEL; Nasal cavity; Oligonol; Toxicology; UV; body weight; bw; epigallocatechin gallate; green tea extract; lowest-observed-adverse-effect level; lychee fruit extract; margin-of-safety; median lethal dose; no-observed-adverse-effect level; one-way analysis of variance; ultraviolet; v/v; volume to volume.

MeSH terms

  • Animals
  • Camellia sinensis*
  • Catechin / analogs & derivatives*
  • Catechin / toxicity
  • Female
  • Fruit
  • Litchi*
  • Male
  • Nasal Cavity / anatomy & histology
  • Nasal Cavity / drug effects*
  • No-Observed-Adverse-Effect Level
  • Phenols / toxicity*
  • Plant Extracts / chemistry
  • Rats
  • Rats, Sprague-Dawley
  • Toxicity Tests, Subchronic

Substances

  • Phenols
  • Plant Extracts
  • oligonol
  • Catechin