Chemical Composition, Repellent, and Phytotoxic Potentials of the Fractionated Resin Essential Oil from Araucaria heterophylla Growing in Tunisia.

The resin essential oil (REO) of the Tunisian Araucaria heterophylla trunk bark was investigated for its chemical composition. Then, it was evaluated for its insecticidal and allelopathic activities. The REO was obtained by hydrodistillation for 9 h (yield of 4.2 % w/w). Moreover, fractional hydrodistillation was carried out at 3-hour intervals, resulting in 3 fractions (R1-R3), to facilitate chemical identification and localization of the aforementioned biological activities. GC/MS analysis of the obtained samples allowed the identification of 25 compounds, representing between 91.2 and 96.3 % of their total constituents, which consisted predominantly of sesquiterpene hydrocarbons, oxygenated sesquiterpenes and diterpene hydrocarbons. α-Copaene (10.8 %), γ-muurolene (5.8 %), α-copaen-11-ol (7.8 %), spathulenol (10.5 %), 15-copaenol (8.2 %), ylangenal (10.3 %), dehydrosaussurea lactone (7.7 %), and sandaracopimaradiene (11.4 %) were identified as major compounds. The second part aimed to assess the impact of the A. heterophylla EO and its three fractions for their insecticidal and repellent activity against Tribolium castaneum (Herbst), a stored grain pest, of which a strong repellent activity was noted. In addition, the studied samples showed high phytotoxic effects against Lactuca sativa. The third fraction (R3) performed a total inhibitory potential on seed germination and seedling growth of the target plant. Furthermore, alongside this discovery, an estimation was conducted through molecular docking analysis. Wherein the main compounds of the studied samples were docked into the active pocket of protoporphyrinogen IX oxidase (PDB: 1SEZ), a key enzyme in chlorophyll biosynthesis. Thus, it is recommended to use the REO of A. heterophylla as a natural herbicide.

Characterization of Volatile Organic Compounds and Essential Oil Profile of Pittosporum tobira (Thunb.) W.T. Aiton Cultivated in Tunisia.

The chemical compositions of the essential oils of Pittosporum tobira organs and of the volatile organic compounds emitted were identified. The EOs are extracted by hydrodistillation and the VOCs by head space. The main EOs compounds are α-neoclovene, ß-caryophyllene and limonene in roots. Viridiflorol in young stems, flowers and young leaves (34.90, 31.60, and 24.60%, respectively), α-cadinol in young stems and leaves, and flowers (13.80, 10.40, and 9.10%, respectively) and (E)-nerolidol in flowers (13.30%). The major detected VOCs are n-undecane, n-nonane, α-cubebene, and α-gurjunene and ß-gurjunene. Principal Component Analysis carried out on the 26 main volatile compounds (relative content exceeding 6%) identified both by HS and in the EOs allowed their classification into two groups; compounds specific to roots and those specific to aerial parts. We can notice that the two methods used to extract P. tobira volatile compounds and identify them are complementary. This study defines and differentiates, for the first time, the specific aroma profile of P. tobira from Tunisia. In addition to its ornamental value, all the organs of this species, could be valued as a source of volatile compounds useful in perfume, cosmetics and as food flavoring products.

Chemical Composition and Insecticidal Activity against Tribolium Castaneum of Thapsia garganica L. Seed Essential Oil.

Due to the several side effects of synthetic pesticides, including environmental pollution, threats to human health, and the development of pest resistance to insecticides, the use of alternative healthy, available and efficient agents in pest management strategies is necessary. Recently, the use of essential oil obtained from aromatic plants has shown significant potential for insect pest management. For this reason, the essential oil isolated from seeds of Thapsia garganica L. was investigated for the first time for its chemical profile, and its toxicity and repellency effects against Tribolium castaneum adults. Qualitative and quantitative analyses of the chemical composition by gas chromatography coupled to mass spectrometry (GC/MS) revealed the presence of 18 organic volatiles representing 96.8 % of the total constituents. The main compounds were 1,4-dimethylazulene (51.3 %) followed by methyl palmitate (8.2 %), methyl linoleate (6.2 %) and costol (5.1 %). Concerning the repellent effect, results revealed that SEO (Seed Essential Oil) was very repellent towards T. castaneum adults, with 100 % repellency after 2 h of exposure. Furthermore, the essential oil exhibited remarkable contact toxicity against T. castaneum (93.3 % of mortality) at the concentration of 10 % (v/v). The median lethal dose (LD50 ) of the topical application of the seed essential oil was 4.4 %. These encouraging outcomes suggested that the essential oil from T. garganica seeds could be considered a potent natural alternative to residual persistent and toxic insecticides.

Wild Vitex agnus-castus L.: Phytochemical Characterization, Acute Toxicity, and Bioactive Properties.

Wild Vitex agnus-castus (VAC) is a Mediterranean plant that is rich in bioactive metabolites. This study aimed to validate, for the first time, the beneficial use of VAC fruits and fruit decoctions (VFDs) through in vitro and in vivo trials. Forty-one volatile components were detected in VAC fruits, with 1,8-cineole (30.3%) comprising the majority. The antioxidant activity of VFD was measured by using different in vitro methods (EC50 of 0.16 mg/mL by ß-carotene bleaching inhibition assay) and by measuring the DNA protection power. Using the disc diffusion assay, the antimicrobial activity of VFD was evaluated, and it exhibited a noticeable anticandidal activity. VFD did not cause any toxicity or mortality in rats treated with doses > 200 mg/kg. Using the acetic acid writhing test, the antinociceptive activity of VFD was measured. Our results showed that VFD at 200 mg/kg exhibited a higher analgesic activity (81.68%) than acetylsalicylic acid used as a positive control (74.35%). Its gastroprotective ability was assessed by HCl/ethanol-induced gastric lesions, which were remarkably inhibited (84.62%) by intraperitoneal administration of VFD. This work helps to validate the popular use of VAC to treat nociceptive, inflammatory, and gastric disorders and encourages researchers to further investigate the identification of pharmacological compounds from this species.

Resilience of Stevia rebaudiana (Bertoni) Bertoni in the Underwater Biospheres of Nemo's Garden®: Adaptation to New Cultivation Systems.

The Nemo's Garden® project is an alternative production system for areas with scarce cultivable land but significant presence of water; thus, it is an interesting intervention to address the climate crisis. This work aimed to evaluate the micromorphological, biochemical, and phytochemical characteristics of Stevia rebaudiana (Bertoni) Bertoni grown underwater compared to the terrestrial specimens. The micromorphological analyses, performed on the leaves using light microscopy, fluorescence microscopy, and scanning electron microscopy, evidenced a general uniformity of the trichome morphotype and distribution pattern. The histochemical investigation indicated the simultaneous presence of terpenes and polyphenols in the trichome secreted material from the underwater samples and a prevailing polyphenolic content in the terrestrial specimens; this was also confirmed by biochemical analyses (26.6 mg GAE/g DW). The characterization of non-volatile components, performed using HPLC-MS, showed similar chemical profiles in all the samples, which were characterized by phenolic compounds and steviol glycosides. The volatile compounds, evaluated using HS-SPME coupled with GC-MS, showed sesquiterpene hydrocarbons as the main class in all the analyzed samples (80.1-93.9%). However, the control plants were characterized by a higher content of monoterpene hydrocarbons (12.1%). The underwater biosphere environment did not alter S. rebaudiana micro-morphological characters, although slight qualitative changes were evidenced for the compounds produced as a response to the growth conditions.

Chemical Composition and Cytotoxic Activity of Eucalyptus torquata Luehm. and Eucalyptus salmonophloia F.†Muell. Trunk Bark Essential Oils against Human SW620 and MDA-MB-231 Cancer Cell Lines.

In recent years, there has been a growing interest in the screening of natural active ingredients from Eucalyptus essential oils because of their evident importance in practical utility and their undeniable therapeutic properties. Based on this, the aim of the present study was to investigate the chemical profile of the essential oils of the trunk bark of Eucalyptus torquata Luehm. (ETEO), and E. salmonophloia F. Muell. (ESEO), growing in Tunisia. The in vitro cytotoxic properties of the extracted EOs were also evaluated against two human cancer cell lines: breast carcinoma cell lines MDA-MB-231 and colorectal cancer cell lines SW620. The analysis by gas chromatography coupled with mass spectrometry (GC/MS) led to the identification of 32 compounds from the ETEO, with the dominant constituents being the monoterpenes trans-myrtanol (73.4 %) and myrtenol (4.7 %), and the apocarotene (E)-ß-ionone (3.9 %). In the case of ESEO, 29 compounds were identified with trans-myrtanol (25.0 %), decanoic acid (22.1 %), nonanoic acid (9.8 %), γ-elemene (6.5 %), γ-maaliene (5.5 %), and α-terpineol (5.3 %) as the main components. The cytotoxicity of EOs against the two chosen cell lines was tested using Crystal Violet Staining (CVS) assay and 5-fluorouracil as a reference drug. The two EOs exhibited a significant dose-dependent inhibition against the viability of the used cell lines. Their inhibitory effects were particularly observed towards SW620 colon carcinoma cells with IC50 values of 26.71±1.22 and 22.21±0.85 µg/mL, respectively, indicating that both oils were more cytotoxic for SW620 cells compared to MDA-MB-231 one.

Volatolomics of Three South African Helichrysum Species Grown in Pot under Protected Environment.

Helichrysum decorum DC, Helichrysum lepidissimum S. Moore, and Helichrysum umbraculigerum are three species traditionally used in the South African medicine. The present work deals with the investigation of the spontaneous emission and the essential oils obtained from these plants cultivated in open field under uniform conditions. Fractions of the volatile organic compounds of the three species were rich in monoterpene hydrocarbons, representing more than 70% of the total composition. Pinene isomers were the most representative compounds: ß-pinene in H. decorum (53.0%), and α-pinene in H. lepidissimum (67.9%) and H. umbraculigerum (54.8%). These latter two species evidenced an important amount of sesquiterpene hydrocarbons (SH) especially represented by γ-curcumene (H. lepidissimum) and α- and ß-selinene (H. umbraculigerum). On the contrary, in the EOs, sesquiterpenes compounds prevailed, representing more than 64% of the identified fraction to reach more than 82 and 87% in H. umbraculigerum and H. lepidissimum, respectively. Although the chemical classes and their relative abundances were comparable among the three species, the individual compounds of EOs showed large differences. In fact, caryophyllene oxide (26.7%) and γ-curcumene (17.4%) were the main constituents in H. decorum, and H. lepidissimum respectively, while neo-intermedeol (11.2%) and viridiflorol (10.6%) characterized H. umbraculigerum.

Influence of the Use of an Ionic Liquid as Pre-Hydrodistillation Maceration Medium on the Composition and Yield of Cannabis sativa L. Essential Oil.

Cannabis sativa L. is a multi-purpose crop, whose resilience, adaptability and soil-enriching properties make it a low-impact production. In the last years, the cultivation of the "industrial" hemp varieties (THC < 0.2%) has been promoted by many Countries, opening a whole new market of hemp-derived products, such as its essential oil (EO). Its distillation might represent an effective method to exploit a residue of the hemp fiber production (flowers), complying with the guidelines of the circular economy. In the present work, different concentrations of an ionic liquid (IL; 1,3-dimethyl-1H-imidazol-3-ium dimethylphosphate) have been studied as a pre-hydrodistillation maceration medium. The EO yields have been evaluated, and their compositions have been analyzed by GC-EIMS. The use of 100% and 90% IL concentrations gave a hydrodistillation yield increment of 250% and 200%, respectively. The 200% yield increase was maintained when the 100% IL was recycled after the hydrodistillation. The lower IL concentrations incremented the cannabinoid and oxygenated sesquiterpene contents, while the opposite was true for sesquiterpene hydrocarbons. The proposed IL-enhanced hydrodistillation medium applied to hemp, studied for the first time in the present work, might be used to both (i) noteworthy increment the hydrodistillation yield and (ii) modulate the obtained EO composition based on the desired final product.

Essential Oil Analysis and Antimicrobial Evaluation of Three Aromatic Plant Species Growing in Saudi Arabia.

Arabian flora is a rich source of bioactive compounds. In this study, we investigated three aromatic plant species with the aim of finding valuable sources of antimicrobial agents against common pathogenic microorganisms. We focused especially on microorganisms, which cause outbreaks of infectious disease during mass gatherings and pilgrimages season in Saudi Arabia. The essential oils of three aromatic plant species were hydrodistilled from flowering aerial parts of Lavandula pubescens Decne. and Pulicaria incisa subsp. candolleana E.Gamal-Eldin, and from leaves, stems, ripe and unripe fruits of Juniperus procera Hochst. Ex Endl. They were subsequently analyzed by gas chromatography-mass spectrometry (GC-MS). The main constituents of L. pubescens were found to be carvacrol (55.7%), methyl carvacrol (13.4%), and ß-bisabolene (9.1%). P. incisa subsp. Candolleana essential oil was rich in linalool (33.0%), chrysanthenone (10.3%), eugenol (8.9%), and cis-chrysanthenol (8.0%); the major components of J. procera essential oil were α-pinene (31.3-62.5%) and δ-3-carene (7.3-30.3%). These essential oils were tested against thirteen American Type Culture Collection (ATCC) strains of Gram-positive and Gram-negative bacteria using the agar diffusion assay. The only effective essential oil was that of L. pubescens and the most sensitive strains were Acinetobacter baumannii, Salmonella typhimurium, Shigella sonnei, Enterococcus faecalis and Staphylococcus epidermidis. Carvacrol, the major constituent of L. pubescens, was tested on these strains and was compared with vancomycin, amikacin, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays of L. pubescens essential oil and carvacrol revealed that Gram-negative strains were more susceptible than the Gram-positive ones.

Essential Oil of Cannabis sativa L: Comparison of Yield and Chemical Composition of 11 Hemp Genotypes.

Cannabis sativa L. is an annual species cultivated since antiquity for different purposes. While, in the past, hemp inflorescences were considered crop residues, at present, they are regarded as valuable raw materials with different applications, among which extraction of the essential oil (EO) has gained increasing interest in many fields. The aim of the present study is the evaluation of the yield and the chemical composition of the EO obtained by hydrodistillation from eleven hemp genotypes, cultivated in the same location for two consecutive growing seasons. The composition of the EOs was analyzed by GC-MS, and then subjected to multivariate statistical analysis. Sesquiterpenes represented the main class of compounds in all the EOs, both in their hydrocarbon and oxygenated forms, with relative abundances ranging from 47.1 to 78.5%; the only exception was the Felina 32 sample collected in 2019, in which cannabinoids predominated. Cannabinoids were the second most abundant class of compounds, of which cannabidiol was the main one, with relative abundances between 11.8 and 51.5%. The statistical distribution of the samples, performed on the complete chemical composition of the EOs, evidenced a partition based on the year of cultivation, rather than on the genotype, with the exception of Uso-31. Regarding the extraction yield, a significant variation was evidenced among both the genotypes and the years of cultivation.

Chemical Composition and Cytotoxic Activity of the Fractionated Trunk Bark Essential Oil from Tetraclinis articulata (Vahl) Mast. Growing in Tunisia.

The aim of the present research was to determine the chemical composition and the cytotoxic effects of Tetraclinis articulata trunk bark essential oil (HEE) obtained by steam distillation and five fractions obtained by normal phase silica chromatographic separation. Chemical analysis allowed the identification of 54 known compounds. Relatively high amounts of oxygenated sesquiterpenes (44.4-70.2%) were detected, mainly consisting of caryophyllene oxide (13.1-26.6%), carotol (9.2-21.2%),14-hydroxy-9-epi-(E)-caryophyllene (3.2-15.5%) and humulene epoxide II (2.6-7.2%). The cytotoxic activity against human mammary carcinoma cell lines (MDA-MB-231) and colorectal carcinoma cell lines (SW620) of the essential oil and its fractions were assessed. All the samples displayed moderate to weak activity compared to 5-fluorouracil. The colorectal carcinoma cell line was relatively more sensitive to the essential oil and its fractions compared to the breast cancer cell line, showing IC50 values from 25.7 to 96.5 µg/mL. In addition, the essential oil and its fraction E.2 revealed a cytotoxic activity against colorectal carcinoma cell line, with IC50 values lower than 30 µg/mL. This is the first report on the chemical composition and cytotoxic activity of the trunk bark essential oil of T. articulata.

Spontaneous emission of volatiles from the male flowers of the early-branching angiosperm Amborella trichopoda.

MAIN CONCLUSION: Volatile emissions were detected for the first time in male flowers of the early-branching angiosperm Amborella trichopoda, suggesting a defensive and attractive double role of these compounds. Flower volatile emissions were detected for the first time in male flowers of the early-branching angiosperm Amborella trichopoda. A mixture of seven volatile compounds is found in flower buds, with limonene resulting as the most abundant compound (67%). Further five volatiles are found in freshly opened flowers, with limonene contributing to 31.7%, followed by decanal (15.5%) and by ethyl octanoate (10.3%). While monoterpene hydrocarbons dominate in flower buds (73.6%), their emission in freshly opened flowers is reduced to 41.1%, while non-terpene derivatives are the most abundant (47.1%) chemical class. These compounds, emitted in low amounts, are possibly linked to pollen, which is considered the only reward offered for insect-pollination in this species.

"Help is in the air": volatiles from salt-stressed plants increase the reproductive success of receivers under salinity.

MAIN CONCLUSION: Salinity alters VOC profile in emitter sweet basil plants. Airborne signals by emitter plants promote earlier flowering of receivers and increase their reproductive success under salinity. Airborne signals can prime neighboring plants against pathogen and/or herbivore attacks, whilst little is known about the possibility that volatile organic compounds (VOCs) emitted by stressed plants alert neighboring plants against abiotic stressors. Salt stress (50 mM NaCl) was imposed on Ocimum basilicum L. plants (emitters, namely NaCl), and a putative alerting-priming interaction was tested on neighboring basil plants (receivers, namely NaCl-S). Compared with the receivers, the NaCl plants exhibited reduced biomass, lower photosynthesis, and changes in the VOC profile, which are common early responses of plants to salinity. In contrast, NaCl-S plants had physiological parameters similar to those of nonsalted plants (C), but exhibited a different VOC fingerprint, which overlapped, for most compounds, with that of emitters. NaCl-S plants exposed later to NaCl treatment (namely NaCl-S + NaCl) exhibited changes in the VOC profile, earlier plant senescence, earlier flowering, and higher seed yield than C + NaCl plants. This experiment offers the evidence that (1) NaCl-triggered VOCs promote metabolic changes in NaCl-S plants, which, finally, increase reproductive success and (2) the differences in VOC profiles observed between emitters and receivers subjected to salinity raise the question whether the receivers are able to "propagate" the warning signal triggered by VOCs in neighboring companions.

Lavandula dentata from Italy: Analysis of Trichomes and Volatiles.

This study presented a micromorphological and phytochemical survey on Lavandula dentata L. cultivated at the Ghirardi Botanic Garden (Toscolano Maderno, BS, Italy). The morphological investigation revealed the presence of peltate, short- and medium-stalked capitate trichomes. The histochemical survey showed terpene production by peltates and medium-stalked capitates, hydrophilic secretions by short-stalked capitates. The phytochemical survey was developed on leaf and flower volatile organic compounds (VOCs) and on the essential oil (EO) from the flowering aerial parts. The VOC profiles represented an element of novelty and were dominated by oxygenated monoterpenes, among which 1,8-cineole and ß-pinene were the most abundant (77.40 %, 7.11 % leaves; 81.08 %, 10.46 % flowers). The EO of L. dentata was dominated by oxygenated monoterpenes with a high percentage of 1,8-cineole (69.08 %), followed by ß-pinene, trans-pinocarveol and myrtenal. Evaluations about the ecological role, the potential biological activity and the sensory attributes were proposed, based on literature contributions.

Chemical Composition Analysis, Antioxidant, and Antibacterial Activities of Eggplant Leaves.

Agricultural by-products represent one of the biggest pollutants for the environment, therefore, investigating new sources for the extraction of bioactive compounds is a topic of great interest for the entire scientific community. This work is aimed at studying the chemical composition (pigments, phenolics, volatile compounds) and biological activities (antioxidant and antimicrobial properties) of young and mature leaves of five eggplant cultivars (Solanum melongena L.) grown in Tunisia (Tizona, A1014, Nawel, A336, and Mirval). Pigment analysis showed no statistical variations between the two types of leaves, whereas higher levels of anthocyanins were recorded in young leaves of three out of five cultivars (24.7-52.8 mg 100 g-1 ). Total phenolic compounds (966.5-2072.6 mg 100 g-1 ) and o-diphenols (343.9-741.2 mg 100 g-1 ) contents varied significantly according to leaf age and cultivar. However, no statistically significant variation between young and mature leaves was found in flavonols and tannins content. As for volatile profiles, 62 constituents were characterized with non-terpene derivatives (52.0-61.6 %) and apocarotenes (19.9-35.6 %) as major chemical classes. Regarding the antioxidant activity, methanol extracts of Tizona cultivar mature leaves displayed important antiradical properties using DPPH, ABTS, and phosphomolybdenum assays (IC50 0.1, 0.2 and 0.01 mg mL-1 , respectively). With regards to reducing power determination, the most active extract was obtained from mature A1014 leaves. Further, young Mirval leaves proved to be significantly active from a bactericidal point of view against Candida albicans and Staphylococcus aureus of 3.1 mg mL-1 and 0.2 mg mL-1 MBC, respectively. In conclusion, eggplant leaves are a noteworthy source of antioxidant and antimicrobial compounds with potential use in the pharmaceutical, the cosmetics and the food industries.

Chemical Composition and Insecticidal Activity of Crithmum Maritimum L. Essential Oil against Stored-Product Beetle Tribolium Castaneum.

Several plant essential oils have been used against diverse insect pests since, unlike conventional pesticides, they pose almost no risk to humans and the environment. For this reason, the essential oil (EO) isolated from the fresh leaves of Crithmum maritimum L. and its fractions (F1 -F5 ) obtained by chromatographic simplification were investigated for their chemical profile, as well as for their toxicity and repellency effects against Tribolium castaneum (Herbst) adults. The analysis by GC/MS allowed the identification of 92.8-99.1 % of the compositions of the total oil (EO) and of its fractions (F1 -F5 ). The EO and its fractions F3 -F5 were characterized by the presence of a high amount of phenylpropanoids (94.4, 94.8, 93.6, and 88.7 %, respectively): in all the samples, dill apiole was the most abundant component (EO: 94.1 %, F3 : 94.6 %, F4 : 93.4 %, and F5 : 83.3 %). In addition, the repellency assay results showed that the volatile fraction F5 and the complete EO exhibited a higher repellency towards T. castaneum (97 % and 93 %, respectively) after 2 h of exposure at the dose of 0.04 µL/cm2 . The median lethal dose of the topical application of the EO was 9 %. Furthermore, the fraction F1 possessed interesting contact toxicity against T. castaneum (80 % of mortality) at the concentration of 10 %. These results suggested that the essential oil of C. maritimum leaves might be used as an alternative to synthetic insecticides in order to prevent insects from damaging the stored products.

Leek or Garlic? A Chemical Evaluation of Elephant Garlic Volatiles.

"Aglione della Valdichiana" is listed among the Traditional Agronomic and Edible Products of Italy, as it is a typical product of the Chiana Valley (Tuscany, Italy). It is also known as "elephant garlic", due to the dimension of its cloves, and, other than in the Italian Mediterranean area, its presence is also reported in North Africa and Southwest Asia. The current botanical classification identifies it as a leek variety (Allium ampeloprasum L.), although its appearance, except for its larger dimensions, resembles that of garlic. In the present study, the spontaneous volatile emission of whole and cut cloves of "Aglione della Valdichiana" (elephant garlic), garlic, and leek has been profiled by headspace solid phase micro-extraction. The results have been subjected to statistical analyses (analysis of variance, hierarchical cluster, and principal component analysis) to assess whether the chemical profile confirmed the botanical proximity of elephant garlic and leek, rather than garlic. The phytochemical volatiles evaluation indicated a higher proximity of elephant garlic to garlic, rather than leek, at least for the Chiana Valley specimen analyzed in this study.

Biological Activities of Aqueous Extracts from Carob Plant (Ceratonia siliqua L.) by Antioxidant, Analgesic and Proapoptotic Properties Evaluation.

The present work describes the volatile compounds profile and phytochemical content of Ceratonia siliqua L. Fifty different components have been identified. Among them, three constituents are shared i.e., 2-methlybutanoic acid, methyl hexanoate and limonene by different common carob preparations: pulp decoction (PD), seeds decoction (SD) and Rob, a sweet syrup extracted from the pulp of the carob pod. Each extract exhibits different volatile aromatic emission profiles. The antioxidant activity of the extracts was evaluated using three methods, DPPH, ABTS and FRAP, producing a dose-dependent response. The IC50, when determined by FRAP, gave the lowest values (0.66 ± 0.01, 0.73 ± 0.05 and 0.55 ± 0.00 mg/mL PD, SD and Rob, respectively). The nociception essay, after intraperitoneal injection of acetic acid in mice, demonstrated that Rob, pulp and seeds decoction extracts showed an efficient inhibition of writhes over time, with persistence over 30 min. The SD decoction revealed the highest efficacy in decreasing the writhing reflex (90.3 ± 1.2%; p < 0.001). Furthermore, the proapoptotic activity of SD against three human cell line, THP-1, MCF-7 and LOVO, evaluated by flow cytometry, showed a significantly stronger proapoptotic activity on colon cancer (LOVO) than on the other cell lines, a phenomenon known as phenotypic selectivity.

Chemical Composition, Antioxidant, Anti-Tyrosinase, Anti-Cholinesterase and Cytotoxic Activities of Essential Oils of Six Algerian Plants.

In this study, the essential oils (EOs) of six Algerian plants (Artemisia campestris L., Artemisia herba-alba Asso, Juniperus phoenicea L., Juniperus oxycedrus L., Mentha pulegium L. and Lavandula officinalis Chaix) were obtained by hydrodistillation, and their compositions determined by GC-MS and GC-FID. The antioxidant activity of the EOS was evaluated via 2,2'-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing/antioxidant power (FRAP) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Moreover, their cytotoxic effect was evaluated-as well as their tyrosinase, acetyl- and butyryl-cholinesterase (AChE and BuChE) inhibitory activities. The chemical analyses detected 44, 45, 51, 53, 26 and 40 compounds in EOs of A. campestris, A. herba-alba, J. phoenicea, J. oxycedrus, M. pulegium and L. officinalis, respectively. A. campestris EO was mainly composed of ß-pinene (20.7%), while A. herba-alba EO contained davanone D (49.5%) as the main component. α-Pinene (41.8%) was detected as the major constituent in both J. phoenicea (41.8%) and J. oxycedrus (37.8%) EOs. M. pulegium EO was characterized by pulegone as the most abundant (76.9%) compound, while linalool (35.8%) was detected as a major constituent in L. officinalis EO. The antioxidant power evaluation revealed IC50 values ranging from 2.61 to 91.25 mg/mL for DPPH scavenging activity, while the FRAP values ranged from 0.97-8.17 µmol Trolox equivalents (TX)/g sample. In the ABTS assay, the values ranged from 7.01 to 2.40 µmol TX/g sample. In the presence of 1 mg/mL of the samples, tyrosinase inhibition rates ranged from 11.35% to 39.65%, AChE inhibition rates ranged from 40.57% to 73.60% and BuChE inhibition rates ranged from 6.47% to 72.03%. A significant cytotoxic effect was found for A. herba-alba EO. The obtained results support some of the traditional uses of these species in food preservation and for protection against several diseases.

Botanical and Genetic Identification Followed by Investigation of Chemical Composition and Biological Activities on the Scabiosa atropurpurea L. Stem from Tunisian Flora.

Scarce information about the phenolic composition of Scabiosa atropurpurea L. is available, and no carotenoid compounds have been reported thus far. In this study the phenolic and carotenoid composition of this plant was both investigated and associated bioactivities were evaluated. Aiming to obtain extracts and volatile fractions of known medicinal plants to valorize them in the pharmaceutical or food industries, two techniques of extraction and five solvents were used to determine the biologically active compounds. Gas chromatography coupled to flame ionization and mass spectrometry and liquid chromatography coupled to photodiode array and atmospheric pressure chemical ionization/electrospray ionization mass spectrometry highlighted the presence of 15 volatiles, 19 phenolic, and 24 natural pigments in Scabiosa atropurpurea L. stem samples; among them, the most abundant were 1,8-cineole, chlorogenic acid, cynaroside, and lutein. Bioactivity was assessed by a set of in vitro tests checking for antioxidant, antibacterial, antifungal, and allelopathic (against Brassica oleracea L. and Lens culinaris Medik) effects. Scabiosa atropurpurea L. stem extracts presented a considerable antioxidant, antibacterial, and allelopathic potential, with less antifungal effectiveness. These results indicate that the volatile fractions and extracts from S. atropurpurea L. stem could be considered as a good source of bioactive agents, with possible applications in food-related, agriculture, and pharmaceutical fields. Genetic investigations showed 97% of similarity with Scabiosa tschiliensis, also called Japanese Scabiosa.