The present study evaluates the acute toxicity study of methanolic extracts of green grapes and black grapes. Although humans have ingested both green and black grapes for centuries and are continuing to do so without reported adverse effects, the current toxicology study presents somewhat little formal evidence regarding their safety.
In present study mice were divided into three groups with three mice per group. First group was kept as control i.e. mice of first group were given only distilled water orally while second and third group’s mice were administered orally with methanolic extracts of black grapes and green grapes respectively. As the accessible literature on Vitis vinifera L. reveals that it is nontoxic and mortality is unlikely at highest starting dose level (2000mg/kg body weight), so according to OECD 423 guidelines limit test was conducted deciding the dose based on 2000mg/kg body weight.
According to the results methanolic extracts of both green and black grapes were well tolerated by mice and they did not produce any kind of adverse effects and no mortalitily was recorded at a dose level as high as 2000mg/kg. No other changes in morphological appearance, body weight or food consumption was found. As far as control group is concerned, no changes were seen in mice belonging to that group too.
Present study can be correlated with the study of Geetha S. and Devaraj A. (2014) on acute toxicity of organic grapes (Vitis vinifera L.). In their study they proved methanolic extract of Vitis vinifera L. fruits as safe and non toxic to be administered orally.
Zeghad N. et al. (2016) also assessed acute oral toxicity of Vitis vinifera L. Fruit’s exract and acknowledged it toxicologically safe without any adverse effects at a high dose level up to 1000gm/kg. Likewise, in a study conducted by Bhaumik A. et al. (2015) ethanolic extracts of black grapes showed no adverse effects on WISTAR rats when administered orally at a dose level of 2000mg/kg.
Similarly, a dietary concentration of 2.0-2.5% Grape Seed Extract and Grape Skin Extract has been proved to be toxicologically safe in the studies conducted by Yamakoshi J. et al. (2002), Wren Allison F. et al. (2002), Bentivegna S.S. and Whitney K.M. (2002). Similar results were documented in several parts of the plant of Vitis vinifera L. Sharma Surendra K.R. et al. (2012) and Suralkar A.A. et al. (2015) reported non toxic properties of ethanolic extracts of Vitis vinifera L. roots and its leaves in their studies respectively.
An assessment report on Vitis vinifera L., folium by European Medicines Agency (2010) states that vine leaf aqueous extract had no toxicological adverse effect when tested upon WISTAR rats as well as on CFI mice. Draksh (Fruits of Vitis vinifera L.) failed to show any signs of adversity or toxicity up to 2000mg/kg body weight in the studies of Hadaginhal R.V. et al. (2011) and Kumar D. et al. (2009).
Kanagarla N.S.S.A.V. et al. (2013) studied that Vitis vinifera L. and its bioactive components have many pharmacological properties and their use does not cause any kind of harmful effect. Moreover, consumption of grape seed extract at the levels of up to 2.0% doesn’t induce any significant toxicological effects. Similar results were obtained in the study of Singh J. et al. (2009) where methanolic extracts of Vitis vinifera L. leaves didn’t show any adverse effect up to maximum dose level of 2000gm/kg of body weight.
In present study acute toxicity was evaluated by ‘Acute toxic class methods (OECD guidelines-423)’. During the surveillance period of 14 days, no significant toxicity occurred. No mortality with minute non-considerable behavioural changes was observed. So, the No-Observed-Adverse-Effect-Level (NOAEL) of methanolic extracts of both green and black grapes was recorded 2000mg/kg. Even a dose higher than 2000mg/kg is expected to be non toxic and safe. This indicates a lack of toxicity and supports the use of both extracts for further pharmacological and biological investigations.