Optimization of the Extraction Conditions of Bioactive Compounds from Ocimum basilicum Leaves Using Ultrasound-Assisted Extraction via a Sonotrode

Sweet basil (Ocimum basilicum) leaves are rich in bioactive compounds that present therapeutic benefits for human health. Ultrasonic-assisted extraction (UAE) is frequently used to obtain phenolic compounds from plants/herbal sources. However, few works have developed multi-variable studies to find the optimal conditions to extract the maximum amount of compounds, especially when applied to UAE via a sonotrode. The purpose of this work was to perform a multi-variable study by 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 a sonotrode were the ethanol/water ratio, amplitude, and time. The analyzed responses were the rosmarinic acid, the sum of phenolic acids, and the sum of phenolic compounds content. The optimal conditions were found to be 50% ethanol/water, 50% amplitude, and 5 min. Twenty 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.

Automated summary

This study conducted a multi-variable study using a Box-Behnken design to extract the highest active compound content from sweet basil leaves. The efficacy of the design was confirmed through ANOVA. The studied parameters for ultrasonic-assisted extraction via a sonotrode were the ethanol/water ratio, amplitude, and time, while the analyzed responses were the content of rosmarinic acid, the sum of phenolic acids, and the sum of phenolic compounds. The optimal conditions were found to be 50% ethanol/water, 50% amplitude, and 5 minutes. When the extraction was conducted under the optimal conditions, 20 bioactive compounds were identified using HPLC-ESI-TOF-MS. Sweet basil may be considered a valuable source of important bioactive substances for pharmaceutical use.