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Callitris glaucophylla Joy Thomps. & L.A.S. Johnson is a coniferous forest species of the Cupressaceae family native to Australia. This species is rich in essential oils (EOs) but few studies about variability and biological activity of these EOs are available in the literature. The purpose of this study was to evaluate the variability of production of C. glaucophylla EOs in relation to the different plant parts (needles, cones and stems) and to investigate their antioxidant, anti-enzymatic and herbicidal properties. EOs were obtained by hydro distillation and analyzed by GC and GC-MS. The antioxidant potential of EOs was assessed by ABTS, FRAP and DPPH assays, their phytotoxic activities were evaluated against germination and shoots and radical growth of Sinapis arvensis, Trifolium campestre, Lepidium sativum and Lolium rigidum. The EOs were evaluated for their possible anti-enzymatic effects with spectrophotometric assay. EOs resulted rich in monoterpenes hydrocarbons (61.04–77.82 %) and oxygenated monoterpenes (19.52–25.26 %). The main compounds were α-pinene as major compound in all plant parts (36.99–59.84 %), 1,8-cineole (19.88 % in stems) and limonene (18.94 % in needles). Herbicidal assays showed that all EOs have remarkable and significant phytotoxicity towards germination, roots, and aerial parts growth of the tested plants, depending on the EO, the doses and tested species. The EOs showed significant free radical scavenging potential and resulted more active against cholinesterases than α-glucosidase and α-amylase. The data obtained constitute an important contribution in selecting and valorizing appropriate forestry tree biomass as sources of antioxidant and phytotoxic molecules for sustainable application in food preservation and weeds control. The activities against the tested enzymes confirmed a possible use of these EOs as natural pesticides.

In continuation of the search of eco-friendly and safe alternatives for chemical pesticide for weeds management, essential oils (EOs) of forestry tree may be a good candidate. Here, the EOs of Eucalyptus maculata were extracted by hydrodistillation and the study of their chemical composition was carried out by GC and GC/MS analysis. The allelopathic effects of E. maculata EOs was tested against two common weeds in Tunisia: Sinapis arvensis (dicot) and Phalaris canariensis (monocot) and Triticum durum as cereal monocot cultivated crop. The application of EOs has been carried out in two stages of growth: pre-emergence and post emergence. Analysis of the EOs resulted in the identification of 46 components representing 97.7% of the total oil. 1.8-Cineole was detected as the principal compound accounted for 42% of the oil totality and oxygenated monoterpenes (61.5%) was the major subclass that characterize E. maculata growing in Tunisia. On pre-emergence stage, Eucalyptus EOs significantly reduced germination and seedling growth of all tested species in a dose dependent manner and the phytotoxic effect of the EOs was differently effective depending on doses and tested species. On post-emergence stage, volatile oil induces a phytotoxic effect against all tested plants, a decrease in relative water content, an increase of relative electrolyte leakage percentage and levels of proline and malondialdehyde contents which explain their significant phytotoxic potential. Thus, E. maculata EOs inhibits germination and seedling growth of tested herbs in pre-emergence stage and post emergence stage, therefore E. maculata EOs shows potential towards weed management.

Chemicals and antibiotics are serious problems that cause the resistance of bacteria and the persistence of chemical residues in food. These chemical products affect human health and promote diseases. Therefore, the use of natural resources, especially plants, appears as an alternative to avoid the harmful impacts of such products. Plant active substances such as essential oils, alkaloids and phenols are of great interest to scientists and have been studied for their biological activities. Essential oils (Eos) from the stems of Santolina africana were extracted by hydrodistillation and analyzed by Gaz Chromatography/Mass Spectrometry (GCMS). The antioxidant activity of crude extracts and Eos was evaluated by the DPPH assay and the antibacterial activity was evaluated by the disc diffusion method and the broth microdilution method against Gram-positive strains (Bacillus subtilis, Staphylococcus aureus) and Gram-negative strains (Escherichia coli, Salmonella paratyphi, and Pseudomonas aeruginosa). S.africana Eos from Morocco and Tunisia were found to be rich in artemisia ketone (35.4% and 44.3%, respectively), santolina alcohol (16.2%and 3.2%, respectively) and isoborneol (6.1% and 26.6%, respectively). Methanol extracts were rich in phenolic and flavonoids contents and showed the highest DPPH radical scavenging activity. Results exhibited the sensitivity of the strains to essential oils from S. africana especially against Grampositive bacteria. This current research will provide new information about this plant that can be used as a natural antioxidant and antibacterial for industrial purposes. [ABSTRACT FROM AUTHOR]

This study focuses on different chemo-types of Tunisian Eucalyptus essential oils (EOs) and their potential for controlling aphids, phytopathogenic fungi, weed germination and seedling growth. The EOs, obtained from Eucalyptus astringens (Maiden) Maiden and Eucalyptus lehmannii (Schauer) Benth. leaves through hydrodistillation, were analyzed using GC-MS. The chemical analysis revealed a significant presence of oxygenated monoterpenes (ranging from 41.0% to 83.0%), primarily 1,8-cineole (ranging from 30.5% to 58.5%), and oxygenated sesquiterpenes, mainly globulol (19.0%) for E. astringens. In contrast, α-pinene (7.0%) was the second most abundant chemical class for E. lehmannii. Statistical analysis demonstrated that both EOs were effective against aphids, fungi, and weeds based on their composition. E. lehmannii showed high efficacy against aphids, causing complete mortality in Aphis fabae Scopoli and an 87.28 ± 0.65% mortality rate in Aphis nerii Fonscolombe at a concentration of 0.6 mg/mL. E. astringens exhibited antifungal activity with consistent inhibitory effects exceeding 50.59 ± 0.87% against Fusarium oxysporum Schltdl., and Sclerotinia sclerotiorum (Lib.) de Bary displayed even higher susceptibility with an inhibition rate of 83.33 ± 1.10%. Similarly, E. lehmannii inhibited fungal growth by nearly 50%, with Fusarium culmorum Schltdl. exhibiting a minimum inhibition rate of 45.59 ± 0.71%. Both EOs also displayed significant herbicidal potential by impeding weed germination and seedling growth. Sinapis arvensis L. was particularly susceptible, with complete inhibition observed at a concentration of 2 mg/mL. Overall, these findings highlight the potential application of these Eucalyptus EOs for bio-control, underscoring their diverse characteristics. [ABSTRACT FROM AUTHOR]

Several foods are used in both the nutraceutical and health sectors; vegetable oils, for example, can prevent the onset of numerous diseases. The properties of these oils are related to their chemical composition and primarily to the presence of fatty acids. The present work aimed to determine the chemical profiles of Argania spinosa, Pinus halepensis, and Pistacia altantica oils, used in traditional Tunisian foods, and to evaluate some biological properties. We evaluated their antioxidant, anti-enzymatic, antimicrobial, and anti-inflammatory properties. Linoleic acid was the main component of the three oils. P. atlantica oil showed more significant inhibitory activity against the enzymes studied than A. spinosa and P. halepensis. All three oils showed similar antioxidant and anti-inflammatory activity. Furthermore, A. spinosa and P. halepensis oils showed antibiofilm activity against P. aeruginosa, with 30–40% inhibition. These results focus on the possible use of these oils in the nutraceutical and healthcare sectors. [ABSTRACT FROM AUTHOR]

Background: While mental work has been shown to favor overconsumption, the present study compared the effect of a cognitive task alone, followed by acute exercise, or performed on a cycling desk, on short-term food intake and appetite in adults. Methods: A total of 19 normal-weight adults randomly completed: resting session (CON), 30-minute cognitive task (CT), 30-minute cognitive task followed by a 15-minute high-intensity interval exercise bout (CT–EX), and 30-minute cognitive task performed on a cycling desk (CT-CD). Energy expenditure was estimated (heart rate–workload relationship), and energy intake (EI; ad libitum) and appetite (visual analog scales) were assessed. Results: Energy expenditure was higher in CT-EX (P <.001) compared with the other conditions and in CT-CD compared with CON and CT (P <.01). EI was higher in CON (P <.05) and CT-CD compared with CT (P <.01). Relative EI was higher in CON compared with CT (P <.05) and lower in CT-EX compared with CT, CT-CD, and CON (all Ps <.001). Area under the curve desire to eat was higher in CON compared with CT (P <.05) and CT-EX (P <.01). Area under the curve prospective food consumption was higher in CON compared with CT-EX (P <.01). Overall composite appetite score was not different between conditions. Conclusion: While cycling desks are recommended to break up sedentary time, the induced increase in energy expenditure might not be enough to significantly reduce overall short-term relative EI after mental work. [ABSTRACT FROM AUTHOR]

Eucalyptus species have been widely employed in the projects of reforestation in Tunisia. Although their ecological functions are controversial, these plants are indeed important to counteract soil erosion, and represent a fast-growing source of fuelwood and charcoal wood. In the present study, we considered five Eucalyptus species, namely Eucalyptus alba, E. eugenioides, E. fasciculosa, E. robusta, and E. stoatei cultivated in the Tunisian Arboreta. The aim was to carry out the micromorphological and anatomical characterization of the leaves, the extraction and phytochemical profile of the essential oils (EOs), and the evaluation of their biological properties. Four of the EOs showed the prevalence of eucalyptol (1,8-cineole) varying from 64.4 to 95.9%, whereas a-pinene predominated in E. alba EO (54.1%). These EOs showed in vitro antioxidant activity, and reduced the oxidative cellular stress as shown by their activity on reactive oxygen species (ROS) production, and modulation of the expression of antioxidant enzymes, such as glutamate-cysteine ligase (GCL) and heme oxygenase-1 (Hmox-1). Moreover, the EOs inhibited the production of nitric oxide (NO), showing anti-inflammatory activity. The data collected suggest that these EOs may be considered a promising therapeutic strategy for inflammation-based diseases and may represent an additional value for the economy of Tunisia. [ABSTRACT FROM AUTHOR]

Lemon balm (Melissa officinalis L.) is one of the rare medicinal plants in Tunisia. It was found only in two sites in the north of Tunisia with a small number of plants. The study of germination under the NaCl and PEG effect showed that Tunisian lemon balm seeds were sensitive to saline and osmotic stress. Morphological and biochemical characterizations of Tunisian M. officinalis were performed. Results showed that the Tunisian populations presented plants with long, broad leaves and weak branching. The major constituent in leaf essential oil was germacrene-D with a percentage ranging from 29.17 to 24.6%, and the major fatty acids were polyunsaturated fatty acids, linoleic acid, ranging from 73.93 to 66.74%. The phenolic content of M. officinalis extract varied significantly among origins which could explain the high variation in antiradical scavenging activity. The evaluation of allelopathic activities showed that the extract of the lemon balm leaves presented an allelopathic effect with the majority of the tested seeds. [ABSTRACT FROM AUTHOR]

Effects of endurance running methods on hematological profile are still poorly known. This study aimed to compare the effects of 2 training regimes; high-intensity interval training (HIIT) and moderate-intensity continuous training (MCT) performed at the same external load on hematological biomarkers in active young men. Sixteen men aged 18-20 years were randomly assigned to HIIT or MCT group. Aerobic capacity and hematological biomarkers were assessed before and after 9 weeks of interventions. At baseline, aerobic and hematological parameters were similar for the 2 groups. After intervention, no significant change was observed in maximal aerobic velocity and estimated VO2max in both groups. Leukocyte (p < 0.01), lymphocyte (p < 0.05), neutrophil (p < 0.05), and monocyte (p < 0.01) count showed significant improvements in response to the MCT compared with the HIIT intervention. The MCT intervention favored an increase in the number of immune cells, whereas the opposite occurred as a result of the HIIT intervention. These findings suggest that MCT interventions might be superior to HIIT regimes in improving immune function in active young men. [ABSTRACT FROM AUTHOR]

Abstract: Chemical composition, antioxidant, and antimicrobial activities of essential oils from 16 wild edible Tunisian Foeniculum vulgare populations were evaluated. The essential oil yields of fennel seeds ranged from 1.2 to 5.06%. GC‐MS analysis revealed the presence of 20 compounds. Except one sample, essential oils from different locations were mainly composed of phenylpropanoid and the major compound was estragole with a percentage ranging from 66.09 to 85%. The phenolic content of fennel oils varied significantly among populations which could explain the high variation in antiradical scavenging activity. Furthermore, essential oils presented antimicrobial activity against several strains. Results showed that the Gram‐positive strains of bacteria were most sensitive to fennel oils. This study encourages the use of wild fennel as a potential source of natural antioxidants and antimicrobial agents and supports an assessment of this species in several application domains. Practical applications: The growing interest in the use of medicinal plants in food and pharmaceutical industries has led to a systematic examination of plant extracts for their biological properties. Wild fennel is one of aromatic and medicinal plant known for its biological and pharmaceutical activities. In this study, chemical composition, antioxidant, and antimicrobial activities of fennel essential oil were analyzed with a view of their industrial applications. The variations in essential oil composition and their biological activities in different populations may provide baseline data for breeding programs and large scale multiplication for commercial cultivation of the best fennel population. [ABSTRACT FROM AUTHOR]