Chemical composition and antioxidant potential of essential oil and methanol extract from Tunisian and French fennel ( Foeniculum vulgare Mill.) seeds

Abstract

This study was designed to examine the effect of provenance on the phytochemical and antioxidant properties of essential oil and methanolic extract from Tunisian and French fennel seeds (FFS). Analysis of the essential oil showed that although the same main compounds were found in Tunisian and FFS cultivars, some differences were present in their proportions allowing to classify them in two chemotypes. The first class was composed by trans‐anethole (63.41%–78.26%) for Tunisian cultivars and the second one by estragole (44.72%–88.92%) for French cultivars. The phenolic composition of all fennel seed extracts was characterized by its richness in quinic acid, 4‐O‐caffeoylquinic acid, p‐coumaric acid, and 4‐O‐caffeoylquinic acid. All fennel seed extracts showed a better antioxidant potential than their essential oils depending on the origin. Principal component analysis showed a dispersion of the cultivars on three groups depending on the chemotype diversity. Practical applications Recently, much attention has been focused on fennel due to the nutritional and health‐protective value of their seeds. Several studies have highlighted the importance of fennel seed extracts and essential oils as key ingredients rich in bioactive compounds serving in formulation of new functional food products. This investigation designed to examine the effect of provenance on phytochemical and antioxidant potentials of Tunisian and French fennel seed extracts and essential oils.

Chemical composition and biological activities of fennel ( Foeniculum vulgare Mill.) essential oils and ethanolic extracts of conventional and organic seeds

“…In addition, there were great differences among the free radical scavenging activities of different extracts and EOs fennel samples, the present result was in agreement with the findings of Ahmed et al., (2019) and Kalleli et al. (2019), suggesting that the free radical scavenging activity of ethanol extracts was superior to that of EOs.…”

“…Also, research conducted by Kalleli et al. (2019) showed that the yield of EO Tunisian fennel seeds ranged from 3.24% to 5.26%). However, concerning ethanolic extract yields, results are similar to the finding of Oktay et al., (2003) since these authors reported 10.95% yield of ethanolic extracts from conventional fennel seeds.…”

“…Kalleli et al. (2019) reported that fennel seed methanol extract from Tunisia (Djerba cultivar) showed the highest amount of phenolic compounds (15.69 mg GAE/g DW). Although, Dua et al., (2013) obtained 16.50 mg GAE/g DW of TPC.…”

“…Recently, Kalleli et al. (2019) evaluated methanol extracts and essential oil F. vulgare seeds from Tunisian and French regions for their radicals scavenging activity by DPPH• assay, β‐carotene assay, and reducing power; they also determined the total phenolic and flavonoid contents in plant extracts. The data obtained showed that both Tunisian and French fennel extracts have strong radical quenching activity which was expressed as IC 50 (defined as the concentration required inhibiting 50% the formation of DPPH radicals) and a considerable content of phenolic flavonoid components.…”

Phytochemicals and bioactive analysis of different sweet tea ( Lithocarpus litseifolius [Hance] Chun ) varieties

“…Due to its broad medical values, L. litseifolius is also called "Guanyin Tea," which means maintaining healthy in Chinese. Similar to other plants, such as kiwifruit and fennel (Kalleli et al, 2019;Saeed et al, 2019), the secondary metabolites and bioactivities of L. litseifolius are significantly affected by the plant genetic variation, geographic location, and cultivars. However, there remain limited studies focusing on the phytochemicals and bioactivities of different L. litseifolius cultivars.…”