Hops (Humulus lupulus L.) is a species that grows spontaneously in Corsica, but the characterization of this species in this territory has not yet been investigated. The main objectives of this study are to explore the features of wild hops from Corsica and to determine the effect of the island terroir on some cultivars in the first year of growth. A multidisciplinary approach consisting of the genetic analysis, morphological comparison and chemical characterization of essential oils was carried out on four wild Corsican hops and three hop cultivars grown in Tettnang, Germany and Corsica, France. The morphological and GC-MS analysis of Corsican wild hops, set cluster coastal samples apart from the one far from the coast. This dissimilarity is supported by the SSR analysis by two of the three coastal accessions. The genetics demonstrate a proximity between the European noble cultivar Tettnanger and the mountain Corsican wild hop from Corte. The morphological comparison between German hops cultivated in Tettnang and in Corsican soil, and the GC-MS characterization of their essential oils’ chemical profiles, show different features between year 0 and year +1 for each sample. This multidisciplinary approach highlights an acclimatization of hop cultivars to the Corsican terroir one year after planting.

Beekeeping directly depends on the floral biodiversity available to honey bees. In tropical regions, where nectar and pollen resources are numerous, the botanical origin of some honey is still under discussion. A precise knowledge of plants foraged by honey bees is useful to understand and certify the botanical origin of honey. In this study, attention was paid to honey samples from the French Guiana Atlantic coast where beekeepers generally place their hives in four types of biotopes: seaside vegetation, mangrove, savannah, and secondary forest. Pollen analysis of 87 honey samples enabled the identification of major plants visited by Africanized honey bees during the dry season (approximately from July to January). Through melissopalynologic analysis, 51 pollen types were identified and classified according to their relative presence. Frequently observed pollens (with relative presence > 50%) in French Guiana kinds of honey were those from Mimosa pudica, Cocos sp., Rhyncospora sp., Avicennia germinans, Paspalum sp., Spermacoce verticillata, Tapirira guianensis, Cecropia sp., Myrtaceae sp., Mauritia flexuosa sp., Solanum sp., and Protium sp. In many honeys, only M. pudica was over-represented (relative frequency > 90%). Color and electrical conductivity in French Guiana honeys exhibit significant variations, with color ranging from 27 mm to 110 mm Pfund, and electrical conductivity ranging from 0.35 to 1.22 mS/cm.

Aspergillus flavus is a cosmopolitan saprophytic fungus that infests several foodstuffs and is associated with adverse effects in humans. In Senegal, significant losses of groundnut production are mainly due to contamination caused by this species. This study evaluated in vitro antifungal activities of Cyperus articulatus, Cyperus rotundus and Lippia alba essential oils against A. flavus isolated from peanut seeds. Essential oils obtained by hydrodistillation of rhizomes of the two Cyperus species and leaves of L. alba were analyzed with GC-DIF and GC-MS. The essential oil yields from C. articulatus, C. rotundus and L. alba were 1.1%, 1.3% and 1.7%, respectively. These three samples had the following chemotypes: (i) mustakone (21.4%)/eudesma-4(15)-7-dien-1β-ol (8.8%)/caryophyllene oxide (5.9%), (ii) caryophyllene oxide (25.2%)/humulene epoxyde 2 (35.0%) and (iii) geranial (46.6%)/neral (34.6%). The three oils tested inhibited the growth of A. flavus at concentrations between 100 and 1000 ppm. The L. alba oil was the most effective with total clearance of A. flavus on PDA. For the essential oils of C. rotundus (93.65%) and C. articulatus (78.11%), the highest inhibition rates were obtained with a 1000 ppm dose. Thus, L. alba oil could be used safely as an effective protector of groundnuts against A. flavus.

The study aimed to investigate the chemical composition and antimicrobial and antioxidant activities of the essential oil from dried seeds of Xylopia aethiopica. The essential oil was obtained by hydrodistillation and analyzed by GC/FID and GC/MS. The essential oil yield was 1.35. Forty-nine compounds were identified in the essential oil with 1,8-cineole (16.3), β-pinene (14.8), trans-pinocarveol (9.1), myrtenol (8.3), α-pinene (5.9), and terpinen-4-ol (5.6) as major components. The antimicrobial activity of this essential oil was studied using disk diffusion and broth microdilution methods on four bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and one fungus (Candida albicans). The essential oil exhibited excellent activity against S. aureus, E. faecalis, and C. albicans and moderate activity against E. coli. Among all strains tested, C. albicans showed the best sensitivity with a MIC of 50mg/mL. The antioxidant activity was examined using a DPPH-free radical scavenging assay. The essential oil of X. aethiopica showed low antioxidant activity (IC₅₀=784.604±0.320mg/mL) compared to that of ascorbic acid and the reference compound (IC₅₀=0.163±0.003mg/mL). The results indicate that consumption of X. aethiopica seeds can reduce the virulence of food-borne pathogens and their resistance to antibiotics.

This study aimed to investigate the variation in the chemical composition of Origanum compactum essential oils (EOs) from four geographically distinct locations. Additionally, we evaluated their antioxidant properties and potential inhibitory effects on acetylcholinesterase (AChE), tyrosinase, and α-glucosidase enzymes and their insecticidal proprieties. Notably, this research also marks the first examination of the mineral composition of O. compactum. The chemical composition was determined using gas chromatography–mass spectrometry (GC-MS), which identified thymol (28.72–80.39%), carvacrol (6.54–61.84%), p-cymene (0.27–8.64%), linalool (1.44–1.96%), and caryophyllene oxide (1.34–1.56%) as the major constituents. Concurrently, inductively coupled plasma atomic emission spectroscopy (ICP-AES) revealed significant levels of macro and microelements, including calcium (295.50–512.20 mg/kg), potassium (195.99–398.45 mg/kg), magnesium (59.70–98.45 mg/kg), and iron (43.55–112.60 mg/kg). The EOs demonstrated notable antiradical activities through DPPH (1,1-diphenyl-2-picrylhydrazyl), FRAP (ferric reducing antioxidant power), and β-carotene bleaching assays. Regarding the insecticidal effect, all studied essential oils showed a significant toxicity against C. capitata adults, and the toxicity was dose and time dependent. The highest insecticidal effect was observed for O. compactum essential oils collected from Gouman (LC₅₀ = 2.515 µL/mL, LC₉₀ = 5.502 µL/mL) after 48 h of treatment. Furthermore, at a concentration of 1 mg/mL, the EOs exhibited strong inhibitory effects against AChE (84.75–94.01%), tyrosinase (84.75–94.01%), and α-glucosidase (79.90–87.80%), highlighting their potential as natural inhibitors of these enzymes. The essential oils of O. compactum contain components that could be used as a basis for synthetizing derivatives or analogs with potential medicinal applications and pest control properties.

Volatiles metabolites from the liverwort Plagiochila porelloides harvested in Corsica were investigated by chromatographic and spectroscopic methods. In addition to already reported constituents, three new compounds were isolated by preparative chromatography and their structures were elucidated by mass spectrometry (MS) and NMR experiments. Hence, an atypic aliphatic compound, named 1,2-dihydro-4,5-dehydronerolidol and two isomers, (E) and (Z), possessing an unusual humbertiane skeleton (called p-menth-1-en-3-[2-methylbut-1-enyl]-8-ol) are newly reported and fully characterized in this work. The in vitro antiprotozoal activity of essential oil and extract of P. porelloides against Trypanosoma brucei brucei and Leishmania mexicana mexicana and cytotoxicity were determined. Essential oil and Et₂O extract showed a moderate activity against T. brucei with IC₅₀ values: 2.03 and 5.18 μg/mL, respectively. It is noteworthy that only the essential oil showed a high selectivity (SI = 11.7). Diethyl oxide extract exhibited moderate anticancer (cancerous macrophage-like murine cells) activity and also cytotoxicity (human normal fibroblast) with IC₅₀ values: 1.25 and 2.96 μg/mL, respectively.