Identification of divergent isolates of Banana Mild Mosaic Virus and development of a new diagnostic primer to improve detection

This study aims to describe the identification and genome sequencing of two isolates of Banana Mild Mosaic Virus, and, based on the virus sequences available in GenBank, to design and test a new diagnostic primer for a routine indexing use

Green Solvent to Substitute Hexane for Bioactive Lipids Extraction from Black Cumin and Basil Seeds

A comparative study of bioactive lipids extraction from black cumin (Nigella sativa L.) and basil (Ocimum basilicum L.) seeds using conventional petroleum-based solvent and green solvent 2-methyltetrahydrofuran (MeTHF) was performed. MeTHF extraction allowed obtaining the highest oil yield in black cumin (34%). Regarding fatty acids composition, linoleic acid (61%) and α-linolenic (78%) were relevant in black cumin and basil green and conventionally extracted oils, respectively. Besides, MeTHF allowed obtaining higher tocopherols and total phenolics contents in black cumin (400 mg/kg of oil and 12 mg EGA/g oil) and basil (317 mg/kg oil and 5 mg EGA/g oil) compared to hexane-extracted ones. The content of major phenolic compounds in the two seed oils, trans-hydroxycinnamic acid, rosmarinic acid, and thymol was enhanced by MeTHF extraction. Furthermore, MeTHF-extracted oils possess stronger antioxidant activities (radical scavenging, total antioxidant, and β-carotene bleaching activities) and high and similar anti-inflammatory capacity to hexane-extracted oils. In conclusion, the results revealed that MeTHF is efficient to replace hazardous solvents to extract oil from black cumin and basil seeds rich in compounds relevant to the human diet, including essential polyunsaturated fatty acids (n-6 and n-3), tocopherols, and phenolic compounds with improved biological activities.Peer reviewe

copper induced changes in nutrient uptake enzymatic and non enzymatic antioxidant systems in horehound marrubium vulgare l

Background: The effect of different concentrations (80, 200 and 300 mg/L) of copper (Cu2+) on physiological parameters of horehound (Marrubium vulgare L.) was studied. Once Horehound was cultivated in pots, element uptake and antioxidant system efficiency have been evaluated.Questions: What is the effect of copper on the physiological parameters of Marrubium vulgare? What are the defense strategies developed by this plant to overcome cupric stress?Species study: horehound (M. vulgare) medicinal plant from the family of Lamiaceae.Study site and dates: Seeds of M. vulgare were issued from a non contaminated wild population in the region of Béja (Northwestern Tunisia). Culture of M. vulgare was conducted in 1 August 2014 and lasted 4 months.Methods: The Cu, Fe, K, Mg and Ca contents have been determined. Total phenolic and flavonoid contents have been determined. The free radical scavenging activity (DPPH test) together with SOD, CAT and APX antioxidant enzymatic activity have been evaluated.Results: In the aerial part extracts, Copper stress reduced the uptake and translocation of the cationic elements Fe2+, K+ and Ca2+, in a Cu2+ concentration-dependent manner. The treatment with copper gives rise to positive effects on antioxidant enzymes activities (SOD and CAT enzymes) and to an increase of total phenol and flavonoid contents. Unexpectedly, no correlation with the anti-radical scavenging activity was observed.Conclusions: M. vulgare possess an intrinsic capability to cope with the Cu stress by activation of the enzymatic and non-enzymatic antioxidant systems.</p

On the effect of initial drying techniques on essential oil composition, phenolic compound and antioxidant properties of anise (Pimpinella anisum L.) seeds

The efect of drying methods (sun, oven and shade drying) on aniseeds was investigated in terms of their essential oils, phenolics and antioxidant activities. The optimum yield of essential oil was found in shade drying (2.62%). Fourteen volatile compounds were determined in all samples with variation of the main component proportions depending on drying methods. Thus, trans-anethole (84.21%) and estragole (3.82%) proportions signiicantly increased in shade drying. The highest total phenol and lavonoid contents of aniseeds were recorded in shade drying (42.70 mg of GAE/g and 53.55 mg of QE/g, respectively) while the lowest contents in oven drying at 60 °C (31.15 mg of GAE/g and 46.20 mg of QE/g, respectively). In all drying methods, naringin (41.04–43.76%), chloroginic acid (23.13–27.19%) and rosmarinic acid (12.26–15.95%) were the predominant phenol compounds. Although shade drying increased the antioxidant activity, aniseed extracts exhibited higher radical scavenging (IC50 = 10.15 μg/mL), reducing power (EC50 = 187.24 μg/mL) and chelating (IC50 = 6.85 mg/mL) capacities than essential oils (IC50 = 114.87 μg/mL, EC50 = 548.05 μg/mL and IC50 = 58.65 mg/mL, respectively). In conclusion, Shade drying method was found to enhance essential oils, phenols and antioxidant activities in aniseeds

Rosmarinus officinalis essential oil as an effective antifungal and herbicidal agent

In order to reduce the use of chemical pesticides, great interest has been focused on environment-friendly biological control agents and botanicals that preserve biodiversity. In this context, our study aimed to assess the antifungal and herbicidal activities of Rosmarinus officinalis essential oil (EO) to find an alternative to synthetic pesticides. The chemical composition of R. officinalis essential oil was determined by gaz chromatography-mass spectrometry analysis (GC-MS). Results showed that R. officinallis EO was rich in monoterpenes and the major constituents were 1,8-cineole (54.6%), camphor (12.27%) and α-pinene (7.09%). However, under laboratory conditions, two tests were carried out. The first one consisted on the study of EO antifungal activity using ELISA microplates and the second one consisted on evaluating the effect of EO on seedling growth of weeds. It was confirmed that this EO significantly inhibits spore germination of Fusarium oxysporum, Fusarium culmorum, Penicillium italicum and at 6 mM, the percentage of inhibition reached 100% on Fusarium oxysporum. Indeed, EO slows down seedling growth of Trifolium incarnatum, Silybum marianum, and Phalaris minor. In fact, EO at 5 mM completely inhibits seed germination. On the other hand, another experiment was carried out to evaluate the herbicidal activity by spraying EO on weeds. This showed that a novel herbicide formulation was set up for the first time to improve the activity of R. officinalis EO on post-emergence. Overall, R. officinalis EO can be suggested as a potential eco-friendly pesticide and suitable source of natural compounds potentially usable as natural pesticides

Evaluation of the Effect of Two Volatile Organic Compounds on Barley Pathogens

This study aimed to determine the effect of Volatile Organic Compounds (VOCs) on some pathogens, these VOCs were emitted during interactions of barley with Fusarium culmorum Schltdl and/or Cochliobolus sativus Shoemaker, two common root rot pathogens. Our work shows that two organic esters: methyl propanoate (MP) and methyl prop-2-enoate (MA) significantly reduced the development of fungi in vitro. Additional tests showed that the esters significantly inhibited spore germination of these pathogens. The activity of these VOCs on a wide range of fungal and bacterial pathogens was also tested in vitro and showed inhibitory action. The effect of the VOCs on infected barley seeds also showed plantlets growing without disease symptoms. MA and MP seem to have potential value as alternative plant protection compounds against barley bioagressors