Enhancement of extraction parameters for bioactive substances from ocimum basilicum leaves through sonotrode-assisted ultrasonic extraction

Abstract

Sweet basil (Ocimum basilicum) leaves are rich in bioactive compounds that present therapeutical benefits for human health. Ultrasonic-assisted extraction (UAE) is frequently used to obtain phenolic compounds in plants. However, few works have developed multivariable studies to find the optimal conditions to extract the maximum amount of compounds, especially applied to UAE via sonotrode. The purpose of this work was to perform a multi-variable study employing a Box–Behnken design to collect the highest active compound content from Ocimum basilicum leaves. The efficacy of the design was endorsed by ANOVA. The studied parameters for UAE via sonotrode were ethanol/water ratio, amplitude and time. The analyzed responses were the rosmarinic acid, sum of phenolic acids and sum of phenolic compounds content. Optimal conditions were found to be 50% ethanol/water, 50% amplitude and 5 min. 27 bioactive compounds were identified by HPLC-ESI-TOF-MS, when the extract was collected by applying the optimal conditions. Ocimum basilicum may be appreciated as a valuable source of important bioactive substances for pharmaceutical use.