Background There is increasing interest in the pharmaceutical and food industries to substitute synthetic chemicals with naturally occurring compounds possessing bioactive properties. Plants are valuable sources of bioactive compounds. The present study investigates the chemical composition and antioxidant, antimicrobial, and anticancer activities of ethanolic extracts (EEs) and essential oils (EOs) from two species in the Lamiaceae family, Ocimum basilicum L. and Thymus algeriensis Boiss. & Reut., cultivated in the Algerian Saharan Atlas. Methods The total flavonoid contents of the plants’ ethanolic extracts were determined by the aluminium chloride method, while the total phenols were determined using the Folin-Ciocalteu method. Essential oils were obtained by hydrodistillation of the aerial parts of the plants and were analysed by GC-MS. The free radical-scavenging ability and antioxidant potential of the plants’ EEs and EOs were probed using the 2, 2-diphenyl-picrylhydrazyl radical-scavenging, ABTS radical-scavenging, ferric-reducing power and phosphomolybdenum assays. The antimicrobial activities were evaluated against several pathogens characteristic of gram-negative bacteria (three species), gram-positive bacteria (three species) and fungi (two species). The microdilution method was used to estimate the minimum inhibitory concentrations (MICs). The oils’ anticancer potential against several cancer types was also studied using the MTT assay and reported as the toxic doses that resulted in a 50% reduction in cancer cell growth (LD 50 ). Results Phenolic compounds in the EEs from both plants were analysed by HPLC and demonstrated a rich flavonoid content. Chemical analysis of the essential oil from Ocimum basilicum revealed 26 unique compounds, with linalool (52.1%) and linalyl acetate (19.1%) as the major compounds. A total of 29 compounds were identified in the essential oil from Thymus algeriensis , with α-terpinyl acetate (47.4%), neryl acetate (9.6%), and α-pinene (6.8%) as the major compounds. The ethanolic extracts and essential oils from both plants exhibited moderate antioxidant activities and moderate to weak antimicrobial activities. Furthermore, anticancer activities against the examined human cancer cell lines were associated with only the EOs from both plants, with LD 50 values ranging between 300 and 1000 μg/mL. Conclusion The results suggest that the bioactive compounds found in the ethanolic extracts and essential oils from Ocimum basilicum and Thymus algeriensis , with diverse antioxidant, antimicrobial and anticancer activities, may have beneficial applications in nutraceutical and pharmaceutical technologies.

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Over the past several decades, there has been a resurgence of interest in industrial hemp (Cannabis sativa L., Cannabaceae) cultivation. Besides fibre, seeds and oil, hemp contains high quantity of essential oil (EO). Hop (Humulus lupulus L., Cannabaceae) is a high-climbing, perennial vine, largely utilized in the brewing industry to add flavour and bitterness to beer. While it is known that hop also contains α- and ß-acids, and terpenes that have been found to be toxic, anti-feedant, and repellent for insects and mites, little is known about the bioactivity against problematic species of the hemp EO. In this study, the chemical composition of the EOs from C. sativa and H. lupulus was evaluated by GC-MS, and their acute toxicity was assessed against the Asian tiger mosquito Aedes albopictus (Skuse) (Diptera Culicidae) and, the freshwater bladder snail Physella acuta (Draparnaud) (Mollusca Physidae), two problematic invasive species. Furthermore, we evaluated the toxicity of both EOs against a non-target insect, the mayfly Cloeon dipterum L. (Ephemeroptera Baetidae). Both EOs were toxic against the three tested species. The most effective EO was the C. sativa, able to kill 100% of P. acuta snails starting from 100 μL L-1. C. sativa LC50 were 301.560, 282.174 and, 35.370 μL L-1, while H. lupulus LC50 were 330.855, 219.787 and, 118.653 μL L-1 against A. albopictus, C. dipterum and P. acuta, respectively. Relative median potency analysis showed that the C. sativa EO was more toxic than H. lupulus against A. albopictus and P. acuta, while H. lupulus was more toxic than C. sativa EO against C. dipterum. The most susceptible species to the two EOs was P. acuta, while A. albopictus resulted the least susceptible one

The nutraceutical properties of extra-virgin olive oil (EVOO) can be further improved by the addition of olive leaves during olive pressing. However, while Citrus leaves are rich sources of bioactive substances, no data are available in the literature about the effect of Citrus leaf addition on the nutraceutical and sensorial profiles of olive oil. This study aimed at comparing the chemical and sensorial qualities of olive oils obtained from ripe olives pressed together with either Olea or Citrus spp. (lemon or orange) cryomacerated leaves. General composition parameters as well as major antioxidants and antioxidant activity were measured. A panel test evaluation, as well as headspace volatile characterization (headspace solid phase microextraction, HS-SPME), were also performed. All data were compared with an EVOO extracted from the same olive batch used as control. It was possible to obtain Leaf Olive Oils (LOOs) characterized by a higher (p < 0.05) content of antioxidants, compared to the control sample, and the highest oleuropein concentration was detected in the olive oil extracted in presence of olive leaf (+50% in comparison with the control). All the LOOs showed a higher smell complexity and the scent of ripe fruit was generally mitigated. Lemon and olive LOOs showed the best smell profile.

BackgroundSynanthropic flies play a considerable role in the transmission of pathogenic and non-pathogenic microorganisms. In this work, the essential oil (EO) of two aromatic plants, Artemisia annua and Artemisia dracunculus, were evaluated for their abilities to control the blowfly Calliphora vomitoria. Artemisia annua and A. dracunculus EOs were extracted, analysed and tested in laboratory bioassays. Besides, the physiology of EOs toxicity and the EOs antibacterial and antifungal properties were evaluated.ResultsBoth Artemisia EOs deterred C. vomitoria oviposition on fresh beef meat. At 0.05 μl cm-2 A. dracunculus EO completely inhibited C. vomitoria oviposition. Toxicity tests, by contact, showed LD50 of 0.49 and 0.79 μl EO per fly for A. dracunculus and A. annua, respectively. By fumigation, LC50 values were 49.55 and 88.09 μl l-1 air for A. dracunculus and A. annua, respectively. EOs AChE inhibition in C. vomitoria (IC50 = 202.6 and 472.4 mg l-1, respectively, for A. dracunculus and A. annua) indicated that insect neural sites are targeted by the EOs toxicity. Finally, the antibacterial and antifungal activities of the two Artemisia EOs may assist in the reduction of transmission of microbial infections/contaminations.ConclusionsResults suggest that Artemisia EOs could be of use in the control of C. vomitoria, a common vector of pathogenic microorganisms and agent of human and animal cutaneous myiasis. The prevention of pathogenic and parasitic infections is a priority for human and animal health. The Artemisia EOs could represent an eco-friendly, low-cost alternative to synthetic repellents and insecticides to fight synanthropic disease-carrying blowflies.