This study was conceived to evaluate the essential fatty acids, secondary metabolites, antiradical and antimicrobial activities of unexploited Tunisian Ziziphus lotus L. The obtained results indicated that the major components of fatty acids were oleic acid (88.12%) and elaidic acid (7.88%). Leaves contained higher amount of total phenols, flavonoids and tannins than fruits, although both methanolic extracts had significant antioxidant activities. Significant correlations were observed between the total phenol or flavonoid contents in methanolic extracts and antioxidant activity estimated by using both 2,2'-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic radical-scavenging methods. In addition, both methanolic extracts exhibited strong antibacterial and antifungal activities. The inhibition zone diameters and the minimal inhibition concentration values were in the range of 10-17 mm and 3.1-50 mg/mL, respectively.

The chemical composition and the biological activities of Mentha pulegium leaves extracts were evaluated. The main components of M. pulegium EO were menthone (41.7%), cis‐isopulegone (31.71%) and isomenthone (15.03%). The methanol extract of M. pulegium was rich in phenols and flavonoids. The EO showed much better antioxidant activity than the methanol extract against the DPPH and ABTS radicals scavenging. The EO showed strong antibacterial and antifungal activities against 10 tested microorganisms (Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa, Aeromonas hydrophila, Listeria monocytogenes, Bacillus cereus, Aspergillus niger, Aspergillus flavus, Candida albicans) tested whereas the methanol extract almost remained inactive. The IZ diameters and minimal inhibitrice concentration values for tested microorganisms were in the range of 15–30 mm and 0.05–0.8% (v/v), respectively. Future studies should focus on to determine the usage ability of M. pulegium EO in foods as natural preservative in effective dose. Practical Applications The replacement of synthetic additives by natural active compounds fosters research on the screening of medicinal plants as sources of new antioxidants. Moreover, such compounds can be used for extension of product shelf life by inhibiting the growth of foodborne spoilage bacteria. This study focused on the evaluation of biological activities of M. pulegium EO because of its application in food industries as a reasonably safe agent. Thus, this species might be a good candidate for further investigation in developing new antioxidants, as well as preservatives in food against the well‐known causal agents of foodborne diseases and food spoilage, particularly E. coli, S. typhimurium, L. monocytogenes, P. aeruginosa and S. aureus.

Ziziphus jujuba pulps are very much appreciated by the inhabitants and have been recently exported. This article reports on the chemical composition (amino acids, polyphenols and sugars) of the pulps of four Z. jujuba ecotypes (Choutrana, Mahdia, Mahres and Sfax). The major amino acids identified were proline, aspartic acid and glutamic acid. Among these, proline was the most abundant amino acid (17.4 mol). Considerable differences in total phenolic contents (15.85 mg/L) were found. Predominant phenols identified by using HPLC were rutin (1.09 mg/L) and chlorogenic acid (2.57 mg/100 g). Sugars isolated from Ziziphus pulps were found at a rate of 43.52%. Using HPLC method, three sugars from the pulp extract were identified: glucose, galactose and sucrose. The Mahdia ecotype was the richest in these sugars with 0.45, 136.51 and 113.28 mg/L, respectively.

To our knowledge, this study is the first to investigate the biological activities of the methanolic extracts of leaves, roots and stems of Ruta chalepensis L. (Rutaceae) in Tunisia. The chemical composition of the essential oil extracted from R. chalepensis leaves was determined by GC-MS. The antioxidant activities of tested essential oil and the methanolic extracts of leaves, stems and roots of R. chalepensis were evaluated using DPPH and ABTS radicals scavenging tests. Their antimicrobial activities were achieved by disc diffusion method and broth dilution assay. The main components of the selected essential oil were menthol (43.92 %) and linalool (42.10 %). Significant differences were found between the total phenol contents and biological activities of the different parts of R. chalepensis. In addition, significant correlations were observed between antioxidant activities and phenolic contents for methanol extracts. In fact, leaves extract presented higher total phenol content than stems and roots extracts. The tested oil showed better antioxidant activity than methanolic extracts. The highest antioxidant activity was recorded in leaves methanolic extract. The latter showed strong antibacterial activity against tested microorganisms, whereas the evaluated oil remained almost inactive. The inhibition zones diameters and minimal inhibitrice concentration values for tested bacteria, which were sensible to different methanolic extracts, were in the range of 8-35 mm and 0.78-25 mg/ml, respectively. This study demonstrated that the R. chalepensis extract can be regarded as promising candidate for natural plant source of antioxidant and antimicrobial agents.

The present study aimed to determine the phytoconstituent compositions of the leaves of four Ziziphus jujuba ecotypes (Choutrana, Mahdia, Mahres and Sfax). The chromatographie peaks of 18 compounds, including nine major fatty acids, live sterols, two triterpene alcohols and two methysterols, were quan tified by the capillary gaseous chromatography method. The major fatty acids identified were linolenic (42.04%) and palmitic (23.04%). Unsaturated fatty acids ranged between 53% and 60%. The predominant sterols (mg/100 g) were 13-sitosterol (4036) and stigmasterol (24. 18). Cycloartenol (68.55 mg/100 g) and citrostadienol (12.27 mg/lOOg) were the major metylsterols. Methylene cydoartanol ranged between 1.2 mg/100 g (Sfax) and 1.5 mg/100 g (Mahdia). Total phenolic content measured by Folin-ciocalteux ranged from 3.97 mg GAE/g to 6.04 mg GAE/g. The predominant flavonoids identified by HPLC were apigenin (6.1 mg/g) and rutin (1.91 mg/g). The fatty acids and flavonoids in the Z. jujuba leaves were responsible for their therapeutic and phar maceutical effects. This could explain whyTunisian people traditionally use it as medicine to treat several pathologies.