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Abstract

The aim of this work was to establish the antioxidant and antimicrobial activity of hydro-alcoholic and aqueous extracts prepared from the leaves of Globularia alypum L. The quantitative estimation of total polyphenols (by the Folin-Ciocalteu method) and total flavonoids (by the method of aluminium trichloride) showed that the aqueous and ethyl acetate extracts had the highest content of phenolic and flavonoid compounds. Moreover, the results of antioxidant power assessed by both method DPPH and phosphomolybdenum indicated that leaves extracts of G. alypum expressed a considerable activity. The evaluation of the antimicrobial effects, using the disc diffusion method from antibacterial screening and the direct contact method from the antifungal activity, indicated strong antibacterial and antifungal activity.

Abstract

This study was conducted to evaluate the insecticidal activity of the endophytic fungus Isaria fumosorosea Wize isolated from Ricinus communis L. against Locusta migratoria L. and Acanthoscelides obtectus Say. To evaluate the insecticidal activity, a mixture of fungal extract and spore suspensions (1x107, 1x106 and 1x105 spores/ml of dissolved extract) were applied against the insects. It was found that I. fumosorosea had a good insecticidal activity, positively proportional to concentration and time after exposure (24, 48, 72 hours). A maximum mortality rate of 80% for A. obtectus and 70% for L. migratoria at 1x107 spores/ml of dissolved extract was recorded. Preliminary phytochemical analyses of the fungal extract revealed the presence of alkaloids, flavonoids and phenols. Additionally, a fungal development on the insects bodies has also been noticed; that is undoubtedly explained the recorded insecticidal activity.

Abstract

This work investigates the interactive effect of six culture media and three photoperiods (darkness, 16h/8h, 8h/16h) on the microtuberization of four potato varieties (Spunta, Désirée, Kondor and Bartina). The objective is to determine the best tuberization under these growing conditions. The measured parameters which are related to the suitability of the tuberization characteristics are: the morphological aspects (shape, position) and the biometric ones (number and diameter of tubers). The obtained results permit to valorize the meristems that constitute the starting explant, and their good organogenetic skills to provide the first generation of micropropagation with healthy vitroplants in a sufficient quantity. Thus, the grown vitroplants on the medium (MS/2+BAP+COU) presented the best values which are related to the percentage of tuberization, the number of microtubercles / vitroplants and weight of tubers. Moreover, the Bartina genotype showed a remarkable superiority over its media and under a 16h/8h photoperiod except for the diameter of the tubers, where this genotype had the best diameter over the medium (MS/2+KIN) under an 8h photoperiod.

Abstract

This short communication presents a second version of the program SpectraView (SV2). The Second Version of SpectraView for Spectra Analysis is based on data collected with 2-m RCC telescope at Rozhen National Astronomical Observatory. This version is equipped with new user interface and other features unavailable in its previous versions. It has also been created using modern programming language and is now compatible with the latest operating systems. The program has been tested on the observations of the five short-period variable stars.

Abstract

The aquatic ecosystem of the Meskiana Valley (wilaya of Oum El Bouaghi) covers a large area with a permanent flow and a semi-arid climate characterized by a strong evapotranspiration. In order to determine the Physico-chemical quality, pollution and salinity of the water of the river of Meskiana and more particularly in its downstream part which is exposed to wastewater discharges, analyses were carried out at the level of three sampling points: witness, the upstream (before spill), downstream (after spill)). In order to prevent the risk of alkalization and salinization of soil, the sodium absorption rate (SAR) and the percentage of sodium were determined and represented on the Wilcox and Riverside diagram. The high concentrations of polluting chemical elements and excessive salinity obtained at the downstream site show a high risk of pollution and salinization.

Abstract

The studies on the marine and freshwater testate amoebae of the Bulgarian Black Sea littoral and some related coastal brackish lakes are briefly reviewed. So far, a total of 184 species and subspecies of testate amoebae from 18 families and 45 genera from orders of Arcellinida and Euglyphida were published in national and international journals. The underground waters of the Bulgarian marine sand supralittoral are better studied than the related continental lakes. A total of about 45 species of marine interstitial testate amoebae are known, so far, and a big part of them were for the first time described from the Black Sea littoral. It’s interesting to note the presence in the marine underground waters of the Black Sea littoral of many freshwater testate amoebae also, considered by us as eurybionts. That is due of the low and variable salinity of the littoral Black Sea waters during the year. The presence of some psammobiotic testate amoebae as Psammonobiotus lineare and Corythionella georgiana in some related brackish lakes is also of ecological interest. The general conclusion of the present synthesis is that the testate amoebae fauna of the Bulgarian Black Sea coast and the related with it many brackish and freshwater littoral lakes is few known yet and need more active researches.

Abstract

The essential oil of the aerial parts of Thymus ciliatus (Desf.) belonging to the Lamiaceae family, was obtained by steam distillation and analyzed by GC-FID and GC-MS. 75 components were identified corresponding to 95.57% of the total oil. The major constituents of the oil were: elemol (6.80%), carvacrol (5.86%), γ-muurolene (5.18%), β-sesquiphellandrene (5.09%), bicyclogermacrene (5.04%), β-pinene (4.49%) and curcumene (4.20%), together with other compounds at relatively low levels: 1,8-cineol (3.66%), β-eudesmol (2.92%), β-bisabolene (2.81%), β-silinene (2.75%), camphor (2.64%), germacrone (2.34%), α-zingiberene (2.12%), δ-cadinene (2.08%), caryophyllene oxide (1.90%), spathulenol (1.88%), □-caryophyllene (1.88%), ar-turmerone (1.79%), α-pinene (1.52%), limonene (1.52%), selina-4,11-diene (1.46%), curzerenone (1.41%), germacrone B (1.37%), bornyl acetate (1.31%), β-farnesene (1.28%), borneol (1.23%), myrtenal (1.16%), zingiberenol (1.15%) and sabinene (1.13%). These results differ from those of previous studies reported on this species collected from other regions of Algeria and Morocco.

Abstract

The present work focuses on an ethnobotanical study of medicinal plants in the Belezma National Park (BNP), which is located in Batna city. It was conducted to precise on the medicinal plants in the park and gathers all the information on the therapeutic practice used by the local inhabitants of the study area. Using 300 questionnaire cards, ethnobotanical surveys of BNP were conducted during two campaigns (2017 and 2018). The obtained results allowed us to identify 50 medicinal plants used by the population of the region, which are divided into 27 families and 46genus.

The obtained results show both leaves and stems are mostly used for diseases’ treatment in the form of a decoction with a rate of 42.34%. For the treated diseases, the digestive disorders occupy the first place with a rate of 34.01%, followed by uro-genital diseases with a rate of 17.56%, 11.20% for respiratory diseases, 11.84% for orthopedic diseases and 6.23% for cardiovascular.

The founded results could be a database for research on phytochemistry and pharmacology for the national medicinal flora and the population of the BNP region. Also, they constitute a very valuable source of information.

Abstract

The objective of the present study was the optimization of the parameters affecting the hydrodistillation of Ruta chalepensis L. essential oil using response surface design type Box-Behnken. After an appropriate choice of three parameters, 15 experiments were performed leading to a mathematical second-degree model relating the response function (yield of essential oil) to parameters and allowing a good control of the extraction process. The realization of the experiments and data analysis was carried out by response surface methodology (RSM). A deduced second-order polynomial expression was used to determine the optimal conditions necessary to obtain a better essential oil yield. These optimized operating conditions were: a granulometry of 2 mm, a condensation-water flow rate of 3.4 mL/min and an extraction time of 204 min. Analysis of variance (ANOVA) indicates that the generated second-order polynomial model was highly significant with R2=0.9589 and P<0.006. The gas chromatography-mass spectrometry analysis of essential oil extracted from the Ruta chalepensis L. aerial parts revealed the presence of 2-undecanone, 2-nonanone and 2-decanone as major components.