Green extraction optimization of bioactive compounds from rosemary (Rosmarinus officinalis L.) using response surface methodology

Abstract

Rosemary (Rosmarinus officinalis L.) is known for its bioactive compounds with high antioxidant potential and pharmacological properties, such as antibacterial, antidepressant and anti-inflammatory. These properties are attributed to the presence of (poly)phenolic compounds. In the literature there is no extraction of these compounds with a totally non-toxic solvent, capable of applying the extract directly to the food. This work aimed to optimize the extraction conditions of bioactive compounds from the rosemary leaves using water as solvent. According to the analysis of variance parameters, a cubic model of high order of significance was obtained with adjusted R2 (R squared) > 0.947. The optimal conditions of the antioxidant potential for conventional and ultrasonic agitation were: Temperature 70 °C, 30 min of extraction and the solvent/solute ratio of 25, resulting in an antioxidant potential of 6861 and 7126 ìmol L.1 Trolox, respectively. The electrospray ionization mass spectrometry (ESI(.)-MS/MS) analysis showed the presence of antioxidant compounds such as: Carnosol (m/z 329.20), rosmanol (m/z 345.03) and rosmarinic (m/z 359.14) acids. The response surface methodology evaluated the influence of the main parameters of the bioactive compounds extraction from rosemary using only water as solvent, in addition to the use of less time and sample mass, resulting in lower cost.