Assessment of phytochemical screening, total phenolic content, antioxidant activity of leaves and stems extract from Adenocarpus bacquei and its essential oil antioxidant activity

Abstract

The researchers’ focus has recently been directed towards finding new natural antioxidants especially those originated from plants. This work is about the screening of phytochemical constituents and the variation of total phenolic and flavonoid content for different parts of Adenocarpus bacquei (leaves and stems) harvested from Morocco. It regards also extracting its essential oil , analyzing its chemical composition by gas chromatography-mass spectrometry (GC/MS) which reveals the presence of 25 compounds where the major one is the (+)-2-Bornanone (38.26%) followed by Eucalyptol (27.74%).Yet, this essential oil proved great antioxidant capacities measured with TAC and DPPH assays. On the other hand, the phytochemical analysis of Adenocarpus bacquei‘s leaves and stems showed the existence of principal groups of secondary metabolites (tannins, flavonoids, mucilage, oses and holosides sterols and triterpenes and combined antraquinons). Quantifying total phenolic and flavonoid content of different crudes extracts of leaves and stems of Adenocarpus bacquei was done using solvents with different polarity (hexane, dichloromethane, ethyl-acetate, ethanol and water). These crude extracts’ total antioxidant activity and radical scavenging activity were respectively evaluated with the phosphomolybdenum and DPPH assays. Therefore, the results showed a simultaneous increasing in total phenolic content of crude extract and the solvent polarity. Yet, the aqueous leaves extract indicates the highest TPC. Also, the results show a significant positive correlation between TAC and DPPH assay in relation with the total phenolic and flavonoid content. These results revealed the powerful capacity of Adenocarpus bacquei’s essential oil and crudes extracts which comes to conclude that Adenocarpus bacquei can be a natural resource of antioxidants.