Safety assessment of aqueous olive pulp extract as an antioxidant or antimicrobial agent in foods

• Published in: Food and chemical toxicology Vol. 44; no. 7; pp. 903 - 915
• Main Authors: Soni, M.G., Burdock, G.A., Christian, M.S., Bitler, C.M., Crea, R.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-07-2006; New York, NY Elsevier Science
• Subjects: Animals; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - toxicity; Antimicrobial; antimicrobial agents; antimicrobial properties; Antioxidant; antioxidant activity; antioxidants; Antioxidants - chemistry; Antioxidants - pharmacokinetics; Antioxidants - toxicity; Biological and medical sciences; embryotoxicity; food preservatives; Food Preservatives - chemistry; Food Preservatives - pharmacokinetics; Food Preservatives - toxicity; Food safety; genotoxicity; HIDROX; Humans; Hydroxytyrosol; intestinal absorption; literature reviews; Medical sciences; nutrient availability; Olea; Olea - chemistry; Olive; olive pulp; oral administration; plant extracts; Plant Extracts - chemistry; Plant Extracts - toxicity; Polyphenols; safety testing; toxicity testing; Toxicology; ORAC; Antimicrobial; FDA; MIC; Antioxidant; Olive; Hydroxytyrosol; RBC; CFU; CAS; NOAEL; Polyphenols; WBC; HIDROX; Food safety; USDA; Toxicity; Extract; Antimicrobial agent; Polyphenol; Plant origin; Phenols; Food
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2006.01.008

The olive fruit, its oil and the leaves of the olive tree have a rich history of nutritional, medicinal and ceremonial uses. Olive oil, table olives and olive products are an important part of the Mediterranean diet, the greatest value of which may be due to olive polyphenols that contribute to the modulation of the oxidative balance in vivo. The objective of this review is to examine the available safety/toxicity literature on olive polyphenols, particularly hydroxytyrosol, to determine the safety-in-use of a standardized aqueous olive pulp extract (HIDROX
®). Among the polyphenols found in the extract, the major constituent of biological significance is hydroxytyrosol (50–70%). In oral bioavailability studies, urinary excretion of hydroxytyrosol and its glucuronide was found to be associated with the intake of hydroxytyrosol. Oral bioavailability of hydroxytyrosol in olive oil and in an aqueous solution was reported as 99% and 75%, respectively. In comparative studies, urinary excretion of hydroxytyrosol was greater in humans than in rats. The LD
50 of the extract and hydroxytyrosol was reported to be greater than 2000
mg/kg. In a subchronic study, the no observed adverse effect level (NOAEL) of the extract in rats was found to be 2000
mg/kg/day. In developmental and reproductive toxicity studies, HIDROX
® did not cause toxicity at levels up to 2000
mg/kg/day. In an in vivo micronucleus assay, oral exposure of rats to HIDROX
® at dose levels up to 5000
mg/kg/day for 29 days did not induce increases in polychromatic erythrocytes in bone marrow. Based on the available studies of the extract and polyphenols, and a history of exposure and use of components of the extract through table olives, olive products and olive oil, the consumption of HIDROX
® is considered safe at levels up to 20
mg/kg/day.