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We investigated the relative contributions of the environment and development stage on total polyphenols, flavonoids and condensed tannins contents, as well as 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide scavenging activities in four Tunisian Mentha pulegium. Shoot total phenolics and antioxidant capacities were significantly dependent on environment, development stage and their interaction. Environment effects were considerably larger than development stage effects for total phenolics, flavonoids, DPPH and superoxide scavenging capacities, whereas development stage was much stronger than environment for tannin content and, although small, interaction effects of the two factors (environment and development stage) were significant for all antioxidant properties analyzed. The highestantioxidant activities were related to high phenolic contents. Three behaviors were revealed; the best antioxidant capacities in Soliman at floral bud stage, followed by Takelsa and the lowest potentialities (Bouarada and Jdeida). These findings indicate that antioxidant properties of M. pulegium were respectively influenced by environment, development stage and their interaction. PRACTICAL APPLICATION Mentha pulegium L. belonging to the Lamiaceae family, which is a highly advanced and homogeneous family, is largely used in food preparation, perfumery, pharmaceutical products and as an insect repellent. In traditional medicine, M. pulegium essential oil is used for digestive, liver and gallbladder disorders, for gout colds and increased micturition and externally for skin diseases ( Gruenwald et al. 1998 ). M. pulegium is a folkloric medicinal plant with interesting shoot antioxidant properties. According to our results, high antioxidant properties of the leaves of M. pulegium might be beneficial to the antioxidant activity. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present work was to study salt effect on the yield and composition of shoot essential oil (EO) and the structures responsible for its biosynthesis in Mentha pulegium L. Shoot EO was extracted by hydrodistillation and composition was determined by GC–MS method. Apical and basal leaves were taken for microscopy analyses; small fresh samples were observed directly without fixation or metallisation with environmental scanning electron microscope (ESEM) and stereomicroscope (SM). Fresh separate epidermis was used for light microscopy (LM). Salt stress enhanced EO yield by about 2.75 times and affected the percentage of menthone, which is the major compound (∼51%), increasing that of pulegone. Menthone, pulegone, and neomenthol constituting the monoterpene class were found to be the principal components. The anatomical study showed three types of trichomes: (i) non-glandular, multicellular, simple hairs; (ii) small, capitate glandular trichomes; (iii) and peltate glandular trichomes. In control plants, the density and size of trichomes varied with leaf side (abaxial or adaxial) and developmental stage. Salt stress results in significant modifications affecting trichome distribution and size on both sides. [Copyright &y& Elsevier]

In this study, Asparagus stipularis was characterized concerning its phytochemical composition, antioxidant potential, cytotoxicity, and pancreatic lipase inhibitory activities. Twenty-seven compounds were identified and quantified by HPLC-DAD-MS in the leaf, stem, pericarp, and rhizome of ethanolic extracts. Seven steroidal saponins were detected, and the highest content was quantified in rhizome and pericap. A. stipularis also contained significant amounts of flavonoids in the aerial part. Isorhamnetin tetra-glycoside, quercetin-3-glucosyl-rutinoside, and rutin were the main flavonoid derivatives in leaf, stem, and pericarp extracts, respectively. In addition, eleven phenolic acids were also detected; among them, caffeic acid, protocatechuic acid, p-hydroxybenzoic acid, and ferulic acid were the predominant phenolics, with these having the highest amounts quantified in the rhizome extracts. All the tested extracts possessed antioxidant capacities, with pericarp and rhizome extracts exhibiting the highest activity in DPPH, ABTS, and FRAP assays. The extracts from pericarp and rhizome were revealed to also be the strongest inhibitors of pancreatic lipase. The rhizome extracts exhibited potent cytotoxic activity against HCT-116 and HepG2 with IC50 values of 30 and 54 µg/mL after 48 h of treatment. The present study demonstrated that A. stipularis can be used as a new source of natural antioxidants and potential anticancer and antiobesity compounds. [ABSTRACT FROM AUTHOR]

Changes in the antioxidant defence systems were investigated in many aromatic and medicinal plants grown under salinity; however, no study is available about its effects on Solanum villosum Mill. In this study, we investigated the response of S. villosum to sodium chloride (NaCl), especially the impacts of NaCl on secondary metabolites production (phenolic compounds, carotenoids, and glycol-alkaloids). For this purpose, a hydroponic culture experiment was conducted on seedlings subjected to 0, 50, 100, or 150 mM NaCl. NaCl affected the growth of S. villosum in terms of plant height and dry weight, however, it increased the water content of the leaves. Although leaf Na+ concentration was significantly increased under salt stress, the leaves K+, Ca2+ and Mg2+ concentration were enhanced and/ or not significantly affected. The adaptation of S. villosum to NaCl stress was also reflected by the maintain of chlorophyll levels under different NaCl treatments. Additionally, leaf caffeic acid, lutein, and beta-carotene contents were considerably increased under 100 mM NaCl treatment, along with the up regulation of some related phenolic (phenylalanine ammonialyase and flavonol synthase), and carotenoid genes (phytoene synthase 1, phytoene synthase 2, and b-lycopene cyclase). The leaf contents of β-solamargine and α-solasonine also increased significantly with increasing salinity. The present study is the first to through some light on the medicinal quality of S. villosum that would be quite helpful for production of secondary metabolites under salt-stressed conditions. [ABSTRACT FROM AUTHOR]

Highlights • CaCl 2 induced osmotic, nutritional, and toxic effects in C. tinctorius plants. • Root Mg uptake efficiency was maintained constant in all treatments. • The uptake selectivity of Mg over Ca substantially increased under CaCl 2 stress. • Mg use efficiency for chlorophyll synthesis was noticeably enhanced under CaCl 2 stress. • CaCl 2 salinity was the dominant stress that oriented plant physiological responses. Abstract CaCl 2 effects on growth, photosynthesis, and Mg nutrition were investigated in safflower ( Carthamus tinctorius L.) plants at low and optimal Mg availability. After seed germination on sand, obtained seedlings were grown under greenhouse conditions and subjected to 3 treatments for 4 weeks: control ( C: 1.5 mM Mg), CaCl 2 salinity ( S: 40 mM CaCl 2 ), and combined effects of CaCl 2 salinity and Mg deficiency ( DS: 0.1 mM Mg and 40 mM CaCl 2 ). The application of 40 mM CaCl 2 severely affected root, stem, young leaf, and old leaf growth. This was due to a combination of the three types of effects (osmotic, toxic, and nutritional). Indeed, in response to CaCl 2 presence under both Mg-sufficient and deficient conditions, photosynthetic activity was reduced by stomatal closure to prevent cell dehydration. As a consequence, plant water status was not severely affected in S treatment and this osmotic effect disappeared under Mg-deficient conditions (DS treatment). Membrane integrity was slightly impaired in both S and DS treatments. Mg and Ca imbalances were also detected although plants exhibited adaptive responses to cope with Mg deficiency coupled or not with excessive Ca accumulation. Treated plants substantially increased Mg/Ca uptake selectivity, which allowed them to maintain Mg uptake efficiency unaffected. They also markedly increased their Mg use efficiency for chlorophyll synthesis. Nevertheless, amongst the three salt effects, nutritional imbalances seem to be the most harmful component. As a whole, the responses of the plant to the combined effects of CaCl 2 application and Mg deficiency were dominated by salinity stress responses. [ABSTRACT FROM AUTHOR]

Abstract: The antioxidant and hepatoprotective activities of hot aqueous extract from Asparagus albus (A. albus) leaf against CCl4‐induced liver damage in rats were investigated. The total phenolic, flavonoid, and condensed tannin contents of hot aqueous extract from A. albus leaf were determined. The antioxidant activity of hot aqueous extract from A. albus leaf was evaluated using the antioxidant capacity, DPPH free radical‐scavenging ability and reducing power assays. Different polyphenolic compounds, namely gallic acid, vanillic acid, 3,4 dimethoxybenzoic acid, catechin, rutin, and quercetin were identified. Oral administration of hot aqueous extract from A. albus leaf to male Wistar, intoxicated with CCl4, demonstrated a significant protective effect by lowering the levels of hepatic marker enzymes (aspartate and lactate transaminases) and by improving the histological architecture of the rat liver. The hot aqueous extract from A. albus leaf attenuated oxidative stress by restoring the activities of superoxide dismutase, catalase, and glutathione peroxidase. This study demonstrated that the hot aqueous extract from A. albus leaf protects rat liver from CCl4‐induced injury and suggests a potential therapeutic use for A. albus plant. Practical applications: The hepatoprotective effects of plant extracts are mainly related to their richness in phenolic compounds. Phenolic compounds are secondary metabolites widely found in plants, mostly represented by phenolic acids and flavonoids. The growing interest in these bioactive antioxidant components is principally due to their antioxidant potential and the association between their consumption and the prevention of some diseases. In this study, a remarkable hepatoprotective effect of the hot aqueous leaf extract obtained from Asparagus albus was detected against CCl4‐induced liver injury in rat and its mechanism was related, at least in part, to its free radical scavenging and antioxidant activity on account of the presence of polyphenols. [ABSTRACT FROM AUTHOR]

The ethanolic extracts from the leaves, pericarps and rhizomes of Asparagus albus L. were investigated for their phytochemical composition, antioxidant (DPPH and FRAP assays), anti-microbial against human pathogenic isolates and cytotoxic (human colon carcinoma HCT-116 cells) activities. The highest flavonoid content was obtained in the leaf extract followed by the pericarp but there were no flavonoids detected in the rhizome. However, the rhizome had a high concentration of saponins. Flavonoid and saponin profiles were similar to those previously described for the triguero Huetor Tajar asparagus landrace. It was found that the pericarp ethanolic extract exhibited higher antioxidant activity than rhizome and leaf extracts. Moreover, the rhizome possessed more evident cytotoxic activity against HCT-116 cells in comparison to leaf and pericarp. All extracts showed varying degrees of antimicrobial activity against most of the human pathogenic isolates. In addition, the leaves showed more powerful inhibitory activities against the maximum number of bacteria and all the fungai isolated and the highest activity was in the pericarp extract against multidrug resistant Pseudomonas aeruginosa (MDR) and Erythromycin resistant Streptococcus agalactiae (ER) with an inhibition zone of 21 mm and 19 mm, respectively. The results show that A. albus could be a new crop with pharmaceutical interest because its richness in bioactive compounds provides considerable benefits for human health. [ABSTRACT FROM AUTHOR]

The agriculture industry is frequently affected by various abiotic stresses limiting plant productivity. To decrease the negative effect of salinity and improve growth performance, some strategies have been used, such as exogenous application of plant growth regulators (i.e. gibberellic acid, GA 3 ), or arbuscular mycorrhizal fungi (AMF) inoculation. To gain insights about the cross-talk effect of exogenous GA 3 application and AMF inoculation on growth under salinity conditions, tomato plants ( Solanum lycopersicum, cv. TT-115) were inoculated or not with the AMF Rhizophagus irregularis and exposed to different treatments during two weeks: 0 M GA 3 + 0 mM NaCl, 10 −6 M GA 3 + 0 mM NaCl, 0 M GA 3 + 100 mM NaCl and 10 −6 M GA 3 + 100 mM NaCl. Results have revealed that AMF inoculation or GA 3 application alone, but especially their interaction, resulted in growth improvement under salinity conditions. The growth improvement observed in AMF-inoculated tomato plants under salinity conditions was mainly associated to ionic factors (higher K concentration and K/Na ratio) while the alleviating effect of GA 3 application and its interaction with AMF appear to be due to changes in the hormonal balance. Foliar GA 3 application was found to increase the active gibberellins (GAs), resulting in a positive correlation between GA 3 and the growth-related parameters. Furthermore, cytokinins, indoleacetic acid and abscisic acid concentrations increased in AMF inoculated or GA 3 treated plants but, notably, in AMF plants treated with GA 3 , which showed improved growth under salinity conditions. This suggests that there is an interactive positive effect between GAs and AMF which alleviates growth impairment under salinity conditions by modifying the hormonal balance of the plant. [ABSTRACT FROM AUTHOR]

Salinity effects on growth and essential oil composition of Tunisian safflower (Carthamus tinctorius) shoots grown in hydroponic medium were investigated. Plants treated with 25 mM NaCl showed remarkable morphological modifications and decrease in shoot dry matter. Under 50 and 75 mM NaCl, plants showed a withering and a drastic reduction in dry matter (50% and 70%, respectively). Under NaCl 25 mM, essential oil yield increased significantly (p<0.05) up to 70% and 27% respectively in plants from Tazarka and Kairouan provenances compared with the control. The major compound in Tazarka essential oil was found to be 1,8-cineole (23.5%) followed by methyl eugenol (18.0%), 1-pentadecene (9.1%) and camphene (9.0%). In plants from Kairouan provenance, the major compounds were 1-pentadecene (22.9%), methyl-eugenol (11.8%), linalool (8.1%) and camphene (7.9%). Whatever the origin, the application of 25 mM resulted in remarkable changes in the content and the percentage of the main oil components with the effect being more pronounced in plants from Tazarka. [ABSTRACT FROM AUTHOR]

Abstract: Diplotaxis species are edible and medicinal plants. This study investigates phenolic contents and biological activities in stems, leaves, and flowers of Diplotaxis harra and Diplotaxis simplex. Flowers exhibited the highest polyphenol content and D. harra was significantly more phenol-rich than D. simplex. Similarly, the highest antioxidant activities were found in D. harra flowers. Fractionation of D. harra extract revealed that 60% MeOH fraction showed the best antioxidant activities. Indeed, flower fractions were assayed for their activity against human pathogenic bacteria and the inhibitory percentages reached 100%. As regards fraction polarity, 60% and 80% MeOH fractions were the most active ones. Moreover, HPLC analysis showed that the main phenolic compound was cafeic acid for the two species, whereas p-Coumaric and 3,4-dimethoxybenzoic acids were identified only in D. simplex and sinapic acid was exclusive to D. harra. Overall, our findings indicate that Diplotaxis flowers could be used as a potent source of natural antioxidants and antibiotics. [Copyright &y& Elsevier]

Abstract: Polyphenols are bioactive molecules exhibiting a lot of scientific attention due to their multiple biological activities. This study compared phenolic contents and antioxidant activity in Cynara cardunculus L. organs and focus on leaf phenolic compounds identification by RP-HPLC and their antibacterial activity. The analyzed organs exhibited different total polyphenol contents (7–14.8 mg GAE g−1 DW). Leaf and seed phenolic contents were similar and two times higher than those in flowers. The same tendency was observed for the amount of flavonoids and tannins. However, seed extracts displayed the highest DPPH ⋅ scavenging ability with the lowest IC50 value (23 μg ml−1), followed by leaves and flowers (over 50 μg ml−1). In contrast, leaves showed the highest capacity to quench superoxide (IC50: 1 μg ml−1) as compared to seeds (6 μg ml−1). In addition, cardoon leaves were efficient to inhibit growth of pathogenic bacteria mainly against Staphylococcus aureus and Escherichia coli. The identification of phenolic compounds from leaves revealed that syringic and trans-cinnamic acids were the major molecules. To cite this article: H. Falleh et al., C. R. Biologies 331 (2008). [Copyright &y& Elsevier]

The phytochemical composition of leaves, stems, pericarps and rhizomes ethanolic extracts of Asparagus acutifolius were characterized by HPLC-DAD-MS. A. acutifolius samples contain at least eleven simple phenolics, one flavonon, two flavonols and six steroidal saponins. The stem extracts showed the highest total phenolic acid and flavonoid contents, where cafeic acid and rutin were the main compounds. No flavonoids were detected in the leaf, pericarp or rhizome while caffeic acid and ferulic acid were the predominant. Steroidal saponins were detected in the different plant parts of A. acutifolius, and the highest contents were found in the rhizome extracts. The stem extracts exhibited the highest antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) and the highest 2,2-azino-bis (3 ethylbenzothiazoline-6-sulphonic acid) (ABTS) scavenging activity was found in the pericarp extracts. The rhizome and leaf extracts showed a potent cytotoxic activity against HCT-116 and HepG2 cell lines. Moreover, the pericarp and rhizome extracts revealed a moderate lipase inhibitory activity. The leaf and rhizome extracts were screened for their antimicrobial activity against human pathogenic isolates. The leaf extract exhibited a powerful inhibitory activity against all the bacteria and fungi tested. [ABSTRACT FROM AUTHOR]