Combination of response surface methodology and UPLC‑QTOF‑MSE for phenolic compounds analysis from Cinnamomum cassia bark as a novel antifungal agent

Abstract

Using the microwave-assisted extraction process, the presented study reports an economic optimization of total phenolic content (TPC) extraction from Cinnamomum cassia bark. Moreover, the investigation on the phenolic profile of extract and the antifungal activity on spoilage pathogens has been performed to boost new applications in the food and pharmaceutical industries. The generated model successfully fits the experimental data, indicating the suitability of response surface methodology in optimizing the extraction of secondary metabolites from cinnamon bark. The optimal TPC output of 153.09 mg gallic acid equivalent/g dry weight (DW) obtained at 400 W, 65 s radiation time, 54% (v/v) acetone concentration and 1:89 liquid to solid ratio was very consistent with the predicted values (151.62 mg GAE/g DW). The phenolic profile of the analyzed extract was investigated by UPLC-QTOF-MSE in the positive electrospray ionization mode and 24 molecules were tentatively identified for the first time in C. cassia. The obtained extract showed strong antifungal activity. The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) ranged from 0.15 to 6.25 mg/ml and 9.37 to 50 mg/ml, respectively. Candida apicola was the most sensitive strain to the cinnamon extract, followed by Alternaria alternata and Aspergillus niger.