Safety assessment of a standardized polyphenolic extract of clove buds: Subchronic toxicity and mutagenicity studies

Abstract

Despite the various reports on the toxicity of clove oil and its major component eugenol, systematic evaluations on the safety of polyphenolic extracts of clove buds have not been reported. Considering the health beneficial pharmacological effects and recent use of clove polyphenols as dietary supplements, the present study investigated the safety of a standardized polyphenolic extract of clove buds (Clovinol), as assessed by oral acute (5 g/kg b.wt. for 14 days) and subchronic (0.25, 0.5 and 1 g/kg b.wt. for 90 days) toxicity studies on Wistar rats and mutagenicity studies employing Salmonella typhimurium strains. Administration of Clovinol did not result in any toxicologically significant changes in clinical/behavioural observations, ophthalmic examinations, body weights, organ weights, feed consumption, urinalysis, hematology and clinical biochemistry parameters when compared to the untreated control group of animals, indicating the no observed-adverse-effect level (NOAEL) as 1000 mg/kg b.wt./day; the highest dose tested. Terminal necropsy did not reveal any treatment-related histopathology changes. Clovinol did not show genotoxicity when tested on TA-98, TA-100 and TA-102 with or without metabolic activation; rather exhibited significant antimutagenic potential against the known mutagens, sodium azide, NPD and tobacco as well as against 2-acetamidoflourene, which needed metabolic activation for mutagenicity.

Effects of clove powder supplementation on performance, blood biochemistry, and immune responses in broiler chickens

“…Hoseini et al (2011) used 300, 500, and 700 mg/L of CLP and observed no effect on serum levels of AST, ALT, and ALP in beluga sturgeon (Huso huso). Moreover, Vijayasteltar et al (2016) reported that CLP inclusion at 0.25, 0.50, and 1.0 g/kg in the diet of rats did not affect AST, ALT, and ALP activity. In another study, Velisek et al (2005) used clove oil at 0.3, 0.5, 0.7, 0.9, and 1.1 g/L and reported unchanged AST, ALT, and ALP in carp.…”

“…The European Union (EU) issued a ban on the use of antibiotics in animal feed in 2006 (Belal et al, 2018). However, researchers contend that herbs, medicinal plants and spices may be alternatives to antibiotics for promoting animal health (Vijayasteltar et al, 2016;Al-Shammari et al, 2017). Cloves, cardamom, anise, ginger, black pepper, and cumin are a group of aromatic plants that are used widely due to their positive effects on growth and health of poultry, probably as a result of their immune stimulatory properties (Chowdhury et al, 2018;Kunnumakkara et al, 2018).…”

Syzygium aromaticum L. (Myrtaceae): Traditional Uses, Bioactive Chemical Constituents, Pharmacological and Toxicological Activities

“…Food and Drug Administration (FDA) has confirmed the safety of clove buds, clove oil, eugenol, and oleoresins as a food supplement; however, there has been considerable attention regarding its toxicity recently [123]. Prashar et al [21] have examined the cytotoxic activities of CEO and eugenol in vitro against human fibroblasts and endothelial cells, and they documented they recognized them as safe.…”

Evaluation of the systemic toxicity and mutagenicity of OLIGOPIN®, procyanidolic oligomers (OPC) extracted from French Maritime Pine Bark extract

“…Given the similarity of Oligopin® to other FMPBE, it is considered reasonable to assume that Oligopin® would have similar properties for each of these toxicological endpoints. It is also of interest to compare the toxicity of Oligopin® with that of proanthocyanidins extracted from grape seeds [ 21 ], and Clovinol, a standardized polyphenolic extract of clove buds [ 25 ], which are also used as nutritional supplements.…”