Phytochemical analysis, in vitro antioxidant and antifungal activities of extracts and essential oil derived from Artemisia herba-alba Asso

Abstract

Artemisia herba-alba Asso is an endemic plant from North-East Morocco offering a diverse range of pharmacological, cosmetic, and agro-ecological uses. However, Artemisia herba-alba has not been well exploited in the field of plant protection (post-harvest diseases). This is why the main objective of the present study is to evaluate the antifungal and antioxidant activities of extracts or the essential oil of this plant. Antifungal activity was assessed against Botrytis cinerea, Penicillium expansum, and Penicillium digitatum using the agar dilution method for the aqueous extracts and fumigation for the essential oil. Antioxidant activity was assessed using the DPPH scavenging test and the FRAP ferric ion reduction capacity. The chemical composition of the extracts was determined by HPLC and that of the essential oil by GC-MS/MS. In addition, the polyphenol, flavonoid, and tannin content was determined using colorimetric methods. The results of this study showed that the total content of polyphenols (217.60 mg GAE/g E), flavonoids (43.59 mg QE/g E), and tannins (32.58 mg GAE/g E) was significantly higher (p ≤ 0.05) in the ethanolic extract than in the aqueous and hexanoic extracts. Moreover, the HPLC analysis of the aqueous extract revealed the presence of six compounds, namely, catechin, gallic acid, hydroxybenzoic acid, syringic acid, caffeic acid, and rutin. In addition, the ethanolic extract was found to contain seven phenolic compounds. On the one hand, 35 compounds were identified in the essential oil of Artemisia herba-alba, representing 99.7% of the total. According to this study, the dominant compounds in the essential oil of Artemisia herba-alba Asso are camphor (46.57%), endo-borneol (5.65%), eucalyptol (5.64%), and thymol (3.85%). Furthermore, the biological evaluation showed that the extracts and essential oil of Artemisia herba-alba have significant antioxidant and antibacterial activities. The findings show that Artemisia herba-alba is a plant that can be used as a source of antifungal chemicals to prevent putrefaction of foodstuffs and, more specifically, postharvest diseases.