Antioxidant capacity and total phenols richness of Cistanche violacea hosting Zygophyllum album

Cistanche violacea is an Orobanchaceae holoparsite hosting chenopodiaceous, including Zygophyllum album. While Cistanche violacea, is known to have edible uses in the folk medicine, no data have been reported before. In the present study, chemical assays were undertaken in order to emphasize the Cistanche violacea antioxidant capacity and total phenols richness. Our data showed higher phenolic contents were measured in Cistanche flowers and Zygophyllum leaves, however Cistanche bulb was the most enriched in flavonoïds. Antioxidant activities were evaluated in methanolic extract of Cistanche violacea flowers and bulb among the host Zygophyllum album leaves. Cistanche flowers and Zygophyllum leaves exhibited the strongest scavenging 2,2-diphenyl-2-picrylhydrazyl radical (DPPH) activity. The metal chelating activity was the highest in Cistanche bulb and Zygophyllum leaves compared to Cistanche flowers. Conversely, the ferric reducing power was significantly higher in Cistanche flowers relative to its bulb and Zygophyllum leaves

Nitrogen Source Differently Regulates Barley (Hordeum vulgare) Response to NaCl Stress At Seed Germination and Early Seedling Development Stages

Nitrogen (N) acts as nutrient and signaling molecule in plants all over their development stages. The involvement of various N forms in the regulation of seed germination response to salt stress was assessed in the present work. Nitrogen sources (NO, NO2−, NO3−, NH4+, glutamine and glutamate) were added at 1mMto the germination medium of barley (Hordeum vulgare, cv Ardhaoui) in combination or not with NaCl stress (14 g.L−1). The application of nitrogen monoxide (NO) alleviated by about 20% the NaCl-induced germination capacity decrease. However, the addition of ammonium ions (NH4+) and glutamic acid (Glu) accentuated the inhibitory effects of NaCl, decreasing germination capacity by about 50% compared to the control. The levels of malondialdehyde (MDA), which is an indicator of membrane lipid peroxidation by stresses, were increased by salinity in seeds treated with nitrite (NO2−), NO3−, Glu and Gln. In N-free medium, NaCl stress induced a severe nitrate reductase activity (NR, EC 1.6.1.6) inhibition. Such an effect was alleviated by the application of N treatments. Glutamate dehydrogenase (GDH, EC 1.4.1.2) aminating activity (NADH-GDH) of seedlings was inhibited by NaCl stress in the presence of NO, Glu and Gln. Conversely, there was stimulation by salt stress of NADH-GDH activity in seedlings treated with NaCl and NH4+. Deaminating GDH activity (NAD-GDH) was found to be enhanced by salt stress in NO2− and NO3− treatments. The differential effects of applied N forms on germination and early seedling development processes in this grass probably underlines different regulatory actions within N mobilization and assimilation

African mustard ( Brassica tournefortii ) as source of nutrients and nutraceuticals properties

Brassica tournefortii is an annual herbaceous plant, native to the North Africa and Middle East. It is considered as an excellent medicinal plant due to its richness by antioxidant like isothiocyanates and polyphenols. The present study is the first phytochemical investigation on Brassica tournefortii organs (leaves, stems, and roots) in terms of nutraceutical, chemical composition, and bioactivity. Brassica tournefortii leaves exhibited the highest values of nutraceutical contents. Interestingly, gas chromatograph‐y‐mass spectrometry (GC‐MS) analysis enabled to identify three new isothiocyanates: iberverin nitrile and iberin detected only in roots, and iberin nitrile detected in all organs. HPLC chromatograms displayed different profiles depending on organic solvent and extracted organ. Icariin and 5,7‐dihydroxy 4‐propylcoumarin showed the highest concentrations with 2.3 and 1.3 mg/g of dr among other molecules identified by high performance liquid chromatography (HPLC). Some phenolic compounds were identified in more than one organ extracts such as phenoxodiol and 4‐hydroxy‐3‐propylbenzoic acid methyl ester. Brassica tournefortii extracts showed a moderate total phenolic contents and anti‐15‐LOX activity, while they exhibited a good anti‐α‐glucosidase activity ranging from 40% to 60%. Furthermore, leaves‐MeOH and root‐dichloromethane (DCM) extracts induced the highest cytotoxicity against MCF‐7 cell lines, while roots‐cyclohexane (CYHA) extract highlighted the highest inhibition activity against, both, HCT‐116 and OVCAR cell lines

Protective effect of Atriplex halimus extract against benzene-induced haematotoxicity in rats

Benzen (BZ) is a ubiquitous environmental pollutant with a toxic effect mainly aimed at the hematopoietic­ and immune systems. Atriplex halimus L. (Amaranthaceae) is a Mediterranean halophytic shrub traditionally used in North Africa as medicinal plant for several therapeutic uses. The present study aimed to estimate the preventive and curative effects of Atriplex halimus L. (Ah) aqueous extract against BZ-induced hematotoxici­ty in rats. Analysis of the extract by the method of LC-MS revealed the presence of 7 vitamins, among which vitamin C content was the highest. Adult rats were divided into five groups as follow: Group 1 received water (control); Group 2 received orally Ah aqueous extract (200 mg/kg) 3 days/week for 15 weeks; Group 3 received BZ (100 mg/kg b.w) daily in drinking water for 15 weeks; Group 4 received concomitantly BZ (100 mg/kg) and preventive treatment with Ah (200 mg/kg) for 15 weeks (AhP+BZ); Group 5 first received BZ (100 mg/kg) for 11 weeks and then curative treatment with Ah extract (300 mg/kg) daily for 30 days (BZ+AhC). It was shown that sub-chronic exposure to benzene induced leukopenia, lymphocytopenia, granulocytopenia and massive degeneration of the bone marrow tissue. The level of GSH and activity of GST and CAT were significantly lowered and the level of MDA was increased in the blood and bone marrow in rats of BZ-intoxicated group compared to the control rats. Administration of Ah extract recovered the bone marrow structure, dramatically decreased MDA content and increased GSH and CAT activity and GST level in the blood and bone marrow as compared with the indices in BZ-treated group. These observations demonstrate that curative and, to a lesser extent, preventive treatment with Atriplex halimus extract have therapeutic potential against hematotoxicity induced by benzene

Réponse à un stress salin croissant de la germination des graines et de la croissance des pousses d’une poacée menacée, Cenchrus ciliaris L.

Cenchrus ciliaris L. (Buffel Grass), a perennial Poaceae, is a threatened species in arid regions of Tunisia. In the present work, involvement of soil salinization on its scarcity is evaluated through studying seeds germination and shoot growth ability under NaCl stress (0, 50, 100, 200 and 300 mM). Our results showed that at moderate stress including 50 and 100 mM NaCl, C. ciliaris sustained sufficient germination capacity (GC ), adequate germination mean time (GMT ) and recovery aptitude (13 %) after transferring seeds to distilled water. Shoot growth was reduced to 50 % by 50 and 100 mM NaCl treatments relative to control, inducing neither lipid oxidation nor tissues dehydration. Salt-induced stimulation of gaïacol peroxidase (GPX, EC. 1.11.1.7) activity seemed to be efficient against oxidative stress. Severe stress, including 200 and 300 mM NaCl, lengthened seeds dormancy, decreased GC and germination rate (increasing GMT) with low germination recovery. While plant growth was not severely affected, increasing malonydialdehyde (MDA) production indicated that 200 and 300 mM NaCl provoked lipid oxidation and that GP X could no longer overcome oxidative stress. It seems that soil salinization with doses greater than 100 mM NaCl may contribute to C. ciliaris scarcity by lowering germination capacity and seedlings growth and establishmentCenchrus ciliaris L. (Cenchrus cilié) est une poacée pérenne cataloguée parmi les espèces menacées dans les régions arides de la Tunisie. Dans le présent travail, l'implication de la salinisation des sols dans la rareté de cette espèce est évaluée par l'étude de la germination des graines et la croissance de la partie aérienne sous stress NaCl (0, 50, 100, 200 et 300 mM). Nos résultats montrent qu'au cours d'un stress salin modéré (50 et 100 mM NaCl), C. ciliaris manifeste une bonne capacité germinative (CG), un temps moyen de germination adéquat (TMG) et une reprise de la germination (13 %) après le transfert de semences à l'eau distillée. La production de biomasse de la partie aérienne est réduite de 50 % pour les traitements 50 et 100 mM NaCl par rapport au témoin, sans toutefois induire l'oxydation des lipides, ni la déshydratation des tissus. L'induction de l'activité gaïacol peroxydase (GPX, EC. 1.11.1.7) semble être efficace dans la lutte contre le stress oxydatif éventuellement provoqué par les doses 50 et 100 mM NaCl. Pour un stress salin sévère (200 et 300 mM NaCl), on constate une augmentation de la dormance des graines, une diminution de la CG, une augmentation du TMG et une faible reprise de la germination après transfert à l'eau distillée. Bien que la production de biomasse aérienne se maintienne à 50 % par rapport au témoin, on a mesuré une augmentation des teneurs en malonydialdehyde (MDA), suggérant que la GPX n'est plus efficace pour lutter contre l'oxydation des lipides membranaires. Il semble qu'une salinisation du sol supérieure à 100 mM NaCl peut contribuer à la raréfaction de C. ciliaris par une diminution de la capacité germinative et de la croissance et de l'implantation des jeunes plants

Kombucha fermentation of African mustard (Brassica tournefortii) leaves: Chemical composition and bioactivity

Brassica tournefortii is an edible vegetable formerly consumed by North African populations. Nowadays, this plant has been neglected and is less used. The present study aims to give an extra nutraceutical value to B. tournefortii using a 2-wk kombucha fermentation process. At the end of incubation, fermented and unfermented (control) B. tournefortii aqueous extracts were successively fractionated with ethyl acetate (EtOAc) and n-butanol to measure their chemical composition and bioactivity. Results showed that kombucha fermentation significantly increased total phenolic content, with the highest amounts in the EtOAc fraction. The antioxidant potential of B. tournefortii leaves was improved by fermentation of EtOAc extracts and conversely lowered in aqueous ones. Anti-acetylcholinesterase activity was increased with fermentation to reach ∼8-fold higher value in B. tournefortii EtOAc and aqueous extracts relative to unfermented samples. Kombucha fermentation was found to reduce cytotoxicity and xanthine oxidase inhibitory effects of B. tournefortii leaves. The findings suggested that fermentation is a promising, simple and safe bioprocess that could improve the food proprieties of less-used edible plan

Volatile and non-volatile profiles of olive pomace and its potential uses

Olive pomace is an environmentally harmful waste from the olive oil industry, containing large amounts of bioactive compounds that could be used in several areas. In the present study, the olive pomace, by-products, was fractionated successively using organic solvents of increasing polarity (cyclohexane (CYHA), ethanol (EtOH) and distilled water) to determine their biochemical composition (total phenolic content, total flavonoid content, HPLC, and GC-MS) and biological activities (antioxidant and antibacterial activities). In addition, the olive pomace was extract directly by the distilled water to determine its physicochemical characteristics (pH, humidity and quantity of oil). The study proved that olive pomace has a low content of total phenolic content in the three extracts (from 0.81 to 2.24 mg GAE/g dry residue). Likewise, for the content of total flavonoids, it presents in the CYHA and EtOH extracts of 0.5 and 0.4 mg QE/g dry residue, respectively. GC-MS data showed the detection of 6 volatile compounds in the cyclohexane extract which contains two major compounds were hexadecanoic acid (2.23%) and 9-octadecenoic acid (8.67%). Moreover, HPLC data showed that chrysin compound was the major one among the four detected ones in the organic extracts of olive pomace. The results showed that the CYHA extract exhibited the best antioxidant power exceeds 50% on the other hand, it is less than 25% for the ethanoic and aqueous extract. In the aqueous extract there is a stronger antibacterial activity against the strain L. monocytogenes (13 mm) than the reference (ampicillin) and the bacterial strain B. cereus (11 mm) associated with their phenolic activity

The Cys-Arg/N-end rule pathway is a general sensor of abiotic stress in flowering plants

Abiotic stresses impact negatively on plant growth, profoundly affecting yield and quality of crops. Although much is known about plant responses, very little is understood at the molecular level about the initial sensing of environmental stress. In plants, hypoxia (low oxygen, which occurs during flooding) is directly sensed by the Cys-Arg/N-end rule pathway of ubiquitin-mediated proteolysis, through oxygen-dependent degradation of group VII Ethylene Response Factor transcription factors (ERFVIIs) via amino-terminal (Nt-) cysteine [1, 2]. Using Arabidopsis (Arabidopsis thaliana) and barley (Hordeum vulgare), we show that the pathway regulates plant responses to multiple abiotic stresses. In Arabidopsis, genetic analyses revealed that response to these stresses is controlled by N-end rule regulation of ERFVII function. Oxygen sensing via the Cys-Arg/N-end rule in higher eukaryotes is linked through a single mechanism to nitric oxide (NO) sensing [3, 4]. In plants, the major mechanism of NO synthesis is via NITRATE REDUCTASE (NR), an enzyme of nitrogen assimilation [5]. Here, we identify a negative relationship between NR activity and NO levels and stabilization of an artificial Nt-Cys substrate and ERFVII function in response to environmental changes. Furthermore, we show that ERFVIIs enhance abiotic stress responses via physical and genetic interactions with the chromatin-remodeling ATPase BRAHMA. We propose that plants sense multiple abiotic stresses through the Cys-Arg/N-end rule pathway either directly (via oxygen sensing) or indirectly (via NO sensing downstream of NR activity). This single mechanism can therefore integrate environment and response to enhance plant survival