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Plants have been seen to possess the potential to be excellent biological matrices to serve as a basis for investigating the presence of promising therapeutic agents for cancer treatment. Several successful anti-cancer medicines - or their analogues - nowadays in use are plant derived and many more are under clinical trials. Under current circumstances, the purpose of this work was to test aqueous and ethanolic extracts of five aromatic and medicinal plants from arid zones on some tumor cell lines. These plants, Cymbopogon schoenanthus (L.) Spreng, Crithmum maritimum (L.) Spreng, Hammada scoparia (Pomel) Iljin, Retama raetam (Forssk.) and Zizyphus lotus (L.) Desf., widely used in Tunisian ethnomedicine, were assessed for their phenolic compounds, antioxidants and anticancer activities in aqueous and ethanol extracts. Total polyphenols, flavonoid and tannin contents were determined colorimetrically and some of these molecules were identified using RP-HPLC. A significant difference on phenolic contents and composition were found among the investigated plants. Cymbopogon schoenanthus was the richest in phenolic compounds (approx. 72%) with quercetine-3-o-rhamnoside (approx. 33%) as main contributor. For all the tested plants, the highest antioxidant capacity was detected in the ethanolic extracts rather than in the aqueous ones. The highest antiproliferative potential was observed for the ethanolic extracts. Hammada scoparia, Retama raetam and Zizyphus lotus exhibited important antiproliferative effect that reached 67% at a 1% extract concentration. Taken together, the present study supports the potential development of chemotherapeutic agents from, at least, four of the five studied Tunisian ethnomedicinal plants.

The fruits of Rhus tripartita had recently attracted great attention due to its notable therapeutic effects. Their potential effects are attributed to the richness of diverse classes of secondary metabolites. The objective of this research was to access the determination of chemical composition and antioxidant properties of R. tripartita fruit extracts and its partitioned fractions (absolute petroleum ether, 70% aqueous ethanol, absolute ethyl acetate and water). LC–ESI-MS/MS and FTIR–ATR were used to assess the potential of R. tripartita fruits as a source of health-promoting constituents. A total of 38 phenolics, including flavones, flavonols, flavanones, organic acids, hydroxycinnamic acids and hydroxybenzoic acids, 26 of them were reported for the first time in R. tripartita. The main compounds were apigenin7-O-glucoside, apigenin and p-coumaric acid. The FTIR–ATR analysis results revealed the presence of characteristic functional groups such as − OH, C–O, − C = C and C–H of phenolic compounds, carboxylic acids, carbohydrates, lipophilic components and proteins in R. tripartita fruits. Furthermore, the ethyl acetate fraction showed the highest level of phenolic contents and strong antioxidant activities. The present study recommends R. tripartita fruits as source of natural antioxidants which can be used as bioactive ingredient for functional foods and nutraceuticals.

Allium roseum L., a spontaneous comestible species in North Africa, presented a nutraceutical potential in terms of essential nutrients and phytonutrients responsible for health benefits. In the present study, growth parameters, soluble sugars, principal secondary metabolites contents (total polyphenols, vitamin C) and their antioxidant properties were determined in A. roseum subjected to salt or drought stresses during 30 days. Plants were subjected to drought stress by suspending watering, while other plants were submitted to salt stress through irrigation with a nutrient solution containing 50, 100, 150 and 200 mM NaCl. The obtained results reveal that salt and drought stress did not significantly affect the growth parameters (p ≥ 0.05), while these stressful conditions increased the bulbs dry matter. Moreover, the applied salt and drought stresses increased the soluble sugars, total polyphenols and vitamin C contents of the plant. Cultivating A. roseum under drought or salt stresses could be a good alternative to valorize antioxidant molecules from this species in industrial applications.

Context The present study deals with new biological properties of the wild edible Diplotaxis simplex (Viv.) Spreng (Brassicaceae). Objectives The current study evaluates the antioxidant, the anti-inflammatory and the anti-cancer properties of ethyl acetate and ethanol extracts from D. simplex flowers. Materials and methods The anti-proliferative activity of the extracts (10-70 μg/mL) was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) against human colon cancer cell line Caco-2. The anti-inflammatory potential was evaluated by the inhibitory effect of the extracts (1.5-7.5 mg/mL) on phospholipase A2 activity as well as on carrageenan-induced paw oedema in mice. Extracts (200 mg/kg) or indomethacin (50 mg/kg) as positive control were injected intraperitoneally for albino mice prior to the induction of the oedema by carrageenan. Antioxidant activities were investigated using various complementary methods. Results Flower extracts contained a high level of polyphenolics (17.10-52.70 mg GAE/g) and flavonoids (74.20-100.60 mg QE/g), which correlate with its appreciable antioxidant potential in β-carotene peroxidation (IC50 value: 12.50-27.10 μg/mL), DPPH(•) radical-scavenging (IC50 value: 0.20-0.40 mg/mL), Fe(3+ )reducing (EC50 value: 0.10-0.14 mg/mL) and Fe(2+ )chelating (IC50 value: 0.20-0.60 mg/mL) assays. These extracts were effective in inhibiting cancer cell growth (IC50 value: 62.0-63.25 μg/mL). Besides, the ethyl acetate extract inhibited phospholipase A2 activity (IC50 value: 2.97 mg/mL) and reduced the paw oedema in mice (from 0.38 ± 0.01 to 0.24 ± 0.01 cm), 4 h post-carrageenan challenge. Conclusion These data suggest that D. simplex may be useful as a candidate in the treatment of inflammation and the colon cancer.

This study deals with the phytochemical analyses, antioxidant and antimicrobial activities screening of Erodium glaucophyllum root bark. Organic extracts (Chloroformic Acid and Ethyl acetate) were screened for their biochemical composition as well as antioxidant and antibacterial activities. Phytochemical screening of Erodium glaucophyllum root bark showed the presence of flavonoids, coumarins, saponins, tannins, antracenosides, phenolics compounds and mucilage. Biochemical screening of the two organic extracts show a highest total polyphenolic content of the two solvent (78.022 ± 0.28 mg GAE/g DM in Chloroform extract and 95.468 ± 0.078 mg GAE/g methyl acetate extract). These values were recorded in the proportion of 70% MeOH. The antioxidant activity was evaluated using DPPH tests, chelation, and the total antioxidant capacity. The antibacterial activity was evaluated by the diffusion test agar vis-a-vis of six bacterial strains. The results show that the levels of polyphenolic content influenced these activities.

Allium roseum leaves were subjected to thin layer convective drying at three temperatures (40, 50 and 60C) and two air velocities (1.0 and 1.5 m/s). The effects of the drying conditions on drying characteristics, color, phenolic compounds and antioxidant properties of A. roseum leaves were assessed. Convective drying induces a considerable moisture removal from fresh leaves (more than 96%) and requires 7 and 28 h at 60 and 40C, respectively. Fresh A. roseum leaves have a water activity higher than 0.9, which had been reduced after drying to a value of about 0.5. Drying resulted in color modifications and drastic declines in total polyphenol content (between 60 and 69%), total flavonoid content (between 17 and 29%) and radical-scavenging capacity (between 72 and 88%). Drying temperature showed a significant effect on drying rate, moisture loss, water activity, total polyphenol content, total flavonoid content and radical-scavenging activity of A. roseum leaves. Practical Applications Allium roseum, also known as rosy garlic, and called in Tunisia “Lazoul,” is a spontaneous plant that grows in the southern part of the country during the rainy years. Local indigenous communities traditionally use Lazoul leaves as a condiment in various meals. The specific taste attributed to these leaves is highly appreciated, but moreover their therapeutic properties, due to antibacterial, antifungal and antioxidant activities, are now well known. However, the short vegetative presence of Lazoul limits its availability and renders it rare. Traditional food prepared with fresh A. roseum leaves tend to disappear, and thus, preparation of such foods, which has been inherited from one generation to the other within a traditional knowledge, is now threatened. Drying may be a solution for A. roseum preservation throughout the year. Moreover, bringing small-scale technologies to local people may revitalize biodiversity and protect traditional food from disappearance.

Total polyphenolic contents (TPC), antioxidant and antibacterial activities of bulb, leaf and flower extracts of the North African endemic plant Allium roseum were studied using three different solvents. Flower and leaf TPCs were found significantly higher than that of bulb with the highest values in methanolic extracts reaching 736.65 ± 88.67 and 749.54 ± 129.15 mg catechol equivalent/100 g of dry material, respectively. The same trend was observed for antioxidant potentials using DPPH. and ABTS.+ scavenging methods. Moreover, the A. roseum phenolic extracts strongly inhibited the growth of a range of microorganisms. Multivariate analysis showed that the extraction solvent and the plant material significantly affected the quantity and bioactivity of the phenolics. Almost all extracts exhibited antioxidant and antibacterial activity; however, the highest values were found in the methanolic extracts of leaves and flowers. These results provide the basis for the use of this edible spontaneous species for fu...

This study deals with the valorisation of medicinal and aromatic Allium to find new bioactive natural products. The phytochemical analyses of A. roseum and A. ampeloprasum powders and their aqueous and organic extracts are achieved. The results show that these species are characterized by the presence, among their components, of three precursors of organosulphurous volatile compounds. They are methiin, isoalliine and alliine in A. roseum and isoalliin and methiin in A. ampeloprasum. These differences in their flavours can correlated with the vicinity of A. roseum with garlic and A. ampeloprasum with onion. Phytochemical screening of Allium roseum shows the presence of active agents such as saponins, tannins, flavonoids, coumarins, steroids, cardiac glycosides, free quinone and iridoids.

This study was conceived to examine the antimicrobial and antioxidant activities of four essential oil types extracted by hydrodistillation from the aerial parts of Artemisia herba-alba cultivated in southern Tunisia. The chemical composition was investigated using both capillary GC and GC/MS techniques. β-thujone, α-thujone, α-thujone/β-thujone and 1,8-cineole/camphor/α-thujone/β-thujone were respectively, the major components of these oil types. The antimicrobial activity of different oils was tested using the diffusion method and by determining the inhibition zone. The results showed that all examined oil types had great potential of antimicrobial activity against strains. In addition, antioxidant capacity was assessed by different in vitro tests and weak activity was found for these A. herba-alba oils.

Melanin performs a crucial role in protecting the skin against harmful ultraviolet light. However, hyperpigmentation may lead to aesthetic problems and disorders such as solar lentigines (SL), melasma, postinflammatory hyperpigmentation and even melanoma. Arthrophytum scoparium grows in the desert in the North African region, and given this type of environment, A. scoparium exhibits adaptations for storing water and produces useful bioactive factors. In this study, the effect of A. scoparium ethanol extract (ASEE) on melanogenesis regulation in B16 murine melanoma cells was investigated. Cells treated with 0.017% (w/v) ASEE showed a significant inhibition of melanin biosynthesis in a time-dependent manner without cytotoxicity. To clarify the mechanism behind the ASEE-treated melanogenesis regulation, the expressions of tyrosinase enzyme and melanogenesis-related genes were determined. Results showed that the expression of tyrosinase enzyme was significantly decreased and Tyr, Trp-1, Mitf and Mc1R mRNA expressions were significantly down-regulated. LC-ESI-TOF-MS analysis of the extract identified the presence of six phenolic compounds: coumaric acid, cinnamic acid, chrysoeriol, cyanidin, catechol and caffeoylquinic acid. The melanogenesis inhibitory effect of ASEE may therefore be attributed to its catechol and tetrahydroisoquinoline derivative content. We report here that ASEE can inhibit melanogenesis in a time-dependent manner by decreasing the tyrosinase protein and Tyr, Trp-1, Mitf and Mc1R mRNA expressions. This is the first report on the antimelanogenesis effect of A. scoparium and on its potential as a whitening agent.

Extracts of aerial parts and roots of wild Astragalus gombiformis Pomel were tested for their antibacterial, antioxidant, and insecticidal activities and contents of phenolic compounds. Antibacterial activity was tested by the paper disk agar diffusion method and determination of the minimal inhibitor concentration. Among the tested extracts, three extracts (methanol, chloroform, and ethyl acetate) from aerial parts and two extracts (water, methanol) from roots exhibited diameters of inhibition zone equal or above 12 mm (at 150 μg/ disk) and minimal inhibitor concentrations ranging between 233 and 1250 μg/ml. Spectrophotometric and HPLC analyses showed that contents of both total polyphenols and flavonoids, as well as antioxidant activity were higher in the methanolic extract of aerial parts as compared to roots. No insecticidal activity of the extracts of the aerial parts was found against Culex pipiens.