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

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

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

Potential distribution and the habitat suitability of the African mustard (Brassica tournefortii) in Tunisia in the context of climate change

The global warming resulting from anthropogenic activities is considered a major threat for the biodiversity in arid and semi-arid regions worldwide. North African countries in western Mediterranean basin, including Tunisia, are expected to experience strong rainfall drop and temperature increase in the next few decades, interrogating the geographical distribution of many plant species in the context of future climate change. Here, ecologically based quantitative climatic envelope model was developed using Maximum Entropy (MaxEnt) to predict current and future distribution of Brassica tournefortii in Tunisia. The data inputs were composed of the species occurrence data and nineteen climatic layers varied over time in line with the predictions created from the global warming scenarios (RCP 4.5 and RCP 6.0) by 2050 and 2070. Using nine uncorrelated variables fitting very well our MaxEnt model, results revealed that the distribution of B. tournefortii was mainly influenced by precipitation-related variables, which contributed with 79.58% in the model, whereas a small contribution was attributed to temperature-related variables (18.20%). Moreover, a noticeable reduction in the current species’ range was recorded, compared with that observed during Last Glacial Maximum (LGM). However, the results suggested a small increase in the areas of very highly, highly, and moderately suitable habitats for the species (0.2, 0.28, and 2.41%, respectively) by 2070 under RCP 6.0. Importantly, we found that the habitat suitability of the species, when applying a climate envelope model, was optimal both along the coastal and the dry South-Western zones of the study area. Overall, the results indicated that B. tournefortii exhibits a great tolerance to severe abiotic constraints of southern Tunisia and seemed to be able to survive under future environmental conditions of its adaptation range. These findings can be used to design reasonable exploitation strategies in order to benefit from the ecological and economical values of B. tournefortii.SCOPUS: ar.jDecretOANoAutActifinfo:eu-repo/semantics/publishe

Brassica Genus Seeds: A Review on Phytochemical Screening and Pharmacological Properties

Traditionally, Brassica species are widely used in traditional medicine, human food, and animal feed. Recently, special attention has been dedicated to Brassica seeds as source of health-promoting phytochemicals. This review provides a summary of recent research on the Brassica seed phytochemistry, bioactivity, dietary importance, and toxicity by screening the major online scientific database sources and papers published in recent decades by Elsevier, Springer, and John Wiley. The search was conducted covering the period from January 1964 to July 2022. Phytochemically, polyphenols, glucosinolates, and their degradation products were the predominant secondary metabolites in seeds. Different extracts and their purified constituents from seeds of Brassica species have been found to possess a wide range of biological properties including antioxidant, anticancer, antimicrobial, anti-inflammatory, antidiabetic, and neuroprotective activities. These valuable functional properties of Brassica seeds are related to their richness in active compounds responsible for the prevention and treatment of various chronic diseases such as obesity, diabetes, cancer, and COVID-19. Currently, the potential properties of Brassica seeds and their components are the main focus of research, but their toxicity and health risks must also be accounted for

Comparative study of local and introduced chard (Perpetual spinach) varieties grown under salt stress. Mehdaoui, M., Mhamdi, R., Mhadhbi, H., Gouia, H., and Debouba, M. (Tunisia)

Unfortunately, many traditional crop germplasms are being abandoned by local farmers and newly introduced varieties are used instead, without any rigorous ecophysiological study regarding their adaptive potential to local environment. In Tunisian arid regions, where salt water is often used for irrigation, a commercial chard (Perpetual spinach) variety Sais has been introduced and is currently replacing an inherited one Arbi of Medenine. In the present work, we aimed to assess the differential response of these two chard varieties (Arbi, Medenine and Sais, Italy) to two salt treatments (7 and 14 g NaCl/l). In both Arbi and Sais shoots, salinity increase led to an endogenous accumulation of sodium and proline associated with a decrease in potassium levels. The lipid peroxidation products (Malondialdehyde, MDA) accumulation in Arbi was considerably greater than in Sais, indicating a higher degree of lipid peroxidation at 14 g/l salt treatment. Salinity stimulated the superoxide dismutase (SOD, E.C. 1.15.1.1), catalase (CAT, EC 1.11.1.6) and guaïacol peroxidase (GPX, EC 1.11.1.7) activities in Arbi shoot, even under severe salt stress (14 g/l). In contrast, these antioxidant enzymes were inhibited by NaCl in Sais shoots. It could be concluded that introduced chard (Sais) exhibited better growth and displayed similar metabolite levels relative to local one (Arbi), but the local chard seems to have stronger antioxidant system that may insure better adaption to water salinity