Toxicological evaluation of pure hydroxytyrosol.

Of all the phenolic constituents of olives and extra virgin olive oil, hydroxytyrosol is currently being actively exploited as a potential supplement or preservative to be employed in the nutraceutical, cosmeceutical, and food industry. In terms of safety profile, hydroxytyrosol has only been investigated as the predominant part of raw olive mill waste water extracts, due to the previous unavailability of appropriate quantities of the pure compound. We report the toxicological evaluation of hydroxytyrosol and, based on the results, propose a No Observed Adverse Effects Level (NOAEL) of 500mg/kg/d.

Genotoxicity, acute and subchronic toxicity studies in rats of a rooster comb extract rich in sodium hyaluronate.

The toxicity of a rooster comb extract (IB0004) that contains mainly sodium hyaluronate was assessed in acute and subchronic studies and in a bacterial reverse mutation assay. In a single dose acute study, male and female rats were administered 2000 mg/kg body weight (bw) of the product and observed for 14 days. No mortality was recorded, thus it was considered that the minimum lethal dose for rats by oral route was greater than 2000 mg/kg bw. A 90-day subchronic study (5, 55 and 600 mg/kg bw/day, oral gavage) with 50 male and 50 female Wistar-Hannover rats produced no significant adverse effects on food consumption, body weight, mortality, clinical biochemistry, hematology, gross pathology, and histopathology. Although some differences were observed between the treated and control animals in body weight gain (%) and some hematological parameters, these changes were generally minor in nature and, are considered to be of no toxicological significance. The no-observable-adverse-effects level was established at 600 mg/kg bw/day. There was no evidence of mutagenic activity in Salmonella typhimurium TA98, TA100, TA1535 and TA1537 or in Escherichia coli WP2 uvra pkM101. In conclusion, the results from these safety studies support the safety of rooster comb extract IB0004 in food.