Modulating and opposite actions of two aqueous extracts prepared from Cinnamomum cassia L. bark and Quercus ilex L. on the gastrointestinal tract in rats

Cinnamon bark and evergreen oak acorns, natural sources of functional ingredients, are effective for those suffering from diarrhea, constipation and irritable bowel syndrome. This study aimed to evaluate the dissimilar phytochemical composition and the opposite potential actions of Cinnamomum cassia bark (ACCE) and Quercus ilex aqueous extracts (GIAE) on gastrointestinal (GI)-physiological activities and disruptions. An HPLC-PDA/ESI-MS assay was used to identify the distinctive qualitative and quantitative profiles of phenolic compounds. The GI-physiological action of both extracts on gastric emptying (GE) and gastrointestinal transit time (GIT) were evaluated using the phenol-red colorimetric method and a test meal containing charcoal/gum arabic in water. Loperamide (LOP)-induced colonic constipation and delayed emptying of the stomach were used to explore the reverse effects of ACCE/GIAE on GI disorders. HPLC-PDA/ESI-MS showed that the main phenolic compounds detected in ACCE are trans-cinnamic acid, quinic acid, protocatechuic acid and rosmarinic acid, while gallic acid, quinic acid and protocatechuic acid are the major chemical constituents found in GIAE. GIAE at two doses (150 and 300 mg kg(−1)) exerted a reduction of GE (66.40% and 60.87%, respectively) compared to a control group (70.25%). However, ACCE at the same concentrations induced contradictory actions on GE/GIT in comparison to GIAE and antagonistic synthetic pharmacological drugs in rats. The protective effect of CCAE against constipation induced by LOP in rats was accompanied by a strong antioxidant property related to moderation of intracellular-mediator disorders. An absence of toxic actions was revealed in the case of the hematological profile and biochemical parameters. Hence, in-depth investigations of these nutrients of both extracts may help future researchers to derive the underlying mechanisms and potential molecular targets for the development of physiologically functional foods and future therapies.