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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]

Ceratonia siliqua L. plant (carob tree) is a Mediterranean species. In Tunisia, the natural distribution of this species is situated in humid zones in the north to the driest ones in the south of the country. Ceratonia siliqua regeneration depends on seeds quality and performances as well as on the practical vegetative propagation tools. Nowadays, carob tree cultivation is limited by the seedlings quality behind the juvenile stage caused by the deterioration of plant root system. This study investigates the effect of lone and mutual root excision technique and mycorrhization on carob seedlings growth performance. Two carob seeds origins were germinated then excised and/or mycorrhized using a sterile substate. For control seedlings, experiment was made without excision nor mycorrhization application. Mycorrhizae applied with excision ameliorated significantly plant length, leaf number, dry and fresh weight of external plant part and roots, collar root diameter and roots branching numbers. Survey of mycorrhizae effects proved also amelioration on carob growth and biomass production but indiscernibly than use of mycorrhization and excision techniques together. Excision alone does not take a part on seedling increasing performance. Mycorrhization of carob species applied with excision increased morphological plant status. Results highlighted the efficiency to use this process to promote plants behaviour by enhancing plant roots and growth in forest areas and agricultural lands. [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]