Optimisation of phytochemical characteristics and antioxidative properties of Foeniculum vulgare Mill. seeds and Ocimum basilicum L. leaves superfine powders using new parting process.

Abstract

Fennel (Foeniculum vulgare Mill.) and basil (Ocimum basilicum L.) are two aromatic medicinal plants. Recently, a new parting process which is named CDS "Comminution and to control Diffraction Sieving" is taken into consideration and its positive effect on the extraction of bioactive compounds from the plants, without any solvent, is reported. Study the effect of CDS on phytochemical properties of superfine powders of fennel seeds and basil leaves. Fennel seeds and basil leaves superfine powders were fractionated as follows: 100-180μm, 180-315μm, 315-500μm, > 500μm and unsieved superfine powders. Extraction of polyphenols was carried out using hydromethanolic maceration. The essential oils were extracted by maceration with dichloromethane. The antioxidant activities were evaluated by DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Using liquid chromatography ultraviolet electrospray ionisation mass spectrometry (LC-UV-ESI-MS), concentrations of characterised phenolic compounds were measured. The essential oils compositions were characterised using gas chromatography mass spectrometry (GC-MS). In fennel seeds, the 100-180μm fraction had maximum antioxidant activity and LC-UV-ESI-MS analyses proved that the best extraction of certain polyphenols was obtained in the 100-180μm fraction. In basil leaves, the best antioxidant activity corresponded to the 315-500μm fraction and LC-UV-ESI-MS analyses showed that the polyphenols were concentrated in the < 315μm fractions. For both plants, GC-MS presented that the essential oils were concentrated in the 315-500μm fraction. CDS as a new green parting process leads to improve the phytochemical properties of these two superfine plant powders in the specific granulometric classes.