In this study, we evaluated the chemical composition and antibacterial activity of the methanolic and aqueous extracts of Eucalyptus blakelyi and Eucalyptus cladocalyx leaves collected from Bainem ...(Algeria). The phytochemical screening results showed that both extracts of these species contained tannins, flavonoids, quinones, coumarines, glycosides, and anthraquinones, in addition to these, methanolic extract was found to contain saponins and alkaloids. Antibacterial activity of the leaf extracts was evaluated against seven bacterial strains. E. blakelyi methanolic and aqueous extracts inhibited the growth of the majority of bacterial strains with significant inhibition against Bacillus subtilis (19.56 mm and 15.13 mm respectively). E. cladocalyx methanolic extract had good inhibitory activity against Micrococcus luteus (14.33 mm). Based on these results, E. blakelyi could be used as a significant source for the secondary metabolites with interesting medicinal properties
In recent years, due to the dramatic increase of the bacteria resistance to antibiotics and chemotherapeutic drugs, an increasing importance is given to the discovery of novel bioactive molecules, ...more potent than those in use. In this contest, methanol extracts of different parts of the medicinal plant Limoniastrum monopetalum (L.) Boiss. (Plumbaginaceae), widely occurring in Tunisia, were prepared to evaluate the antimicrobial and antiproliferative activities. The methanol extract of the roots showed the highest antibacterial activity against E. coli, S. aureus and E. faecalis, whereas the stem extract exhibited the highest antiproliferative effects towards a Hela cell line. Analysis of volatile fractions, using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID) techniques, led to the identification of camphor as the most abundant constituent, which represented from 84.85 to 99.48% of the methanol extracts. Multiple chromatographic separation of the methanol leaf extract afforded the flavonoid maeopsin-6-O-glucoside (S1) and a few fractions that were subjected to biological activity assays. One fraction exhibited interesting antibacterial activity against E. coli and E. faecalis (MIC values of 62.5 and 78.12 µg/mL, respectively), and antiproliferative effects against Hela and A549 cells (IC
= 226 and 242.52 μg/mL, respectively). In addition, in silico studies indicated that maesopsin-6-O-glucoside, which was moderately active against Staphylococcus aureus, strongly interacted with the active site of the accessory gene regulator protein A (AgrA) of Staphylococcus aureus.
The South American tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), invaded Algeria in 2008 and caused severely significant devastation to tomato plants. This study designed to ...evaluate the thermal requirements and assess the influence of temperature on the life cycle of this devastating pest under controlled greenhouse environment. Through a series of experiments, we observed four generations of T. absoluta at various temperatures and relative humidity levels. We chased the population dynamics by using pheromone traps and revealed four overlapping generations, each of which corresponded to peaks in adult flying activity. These peaks were influenced by the greenhouse's temperature and humidity levels. The development of successive and overlapping generations of T. absoluta requires temperatures ranging from 25 to 30 °C, coupled with humidity levels between 58.5 % and 69.33 %. Additionally, the morphometric analysis of T. absoluta larvae allowed the identification of four larval stages characterized by lengths of 2.5 mm for the first instar, 2.5 to 4 mm for the second instar, 4.5 to 5.5 mm for the third instar, and 6 to 7 mm for the fourth instar. By studying the biology of T. absoluta and its thermal and hygrometric requirements, we can develop an integrated pest management strategy that efficiently battles against this destructive pest.
Durum wheat is used predominantly for pasta and couscous but the use of durum wheat for breads is also common in Mediterranean countries. High molecular weight (HMW-GS) and Low molecular weight ...glutenin subunits (LMW-GS) play an important role in determining the bread quality of durum wheat. In this study we used twenty one local and introduced durum wheat varieties cultivated in Algeria, that were grown in the same environmental conditions. These cultivars were evaluated for their variability in several traits related to technological qualities. The present study showed the presence of significant differences within our genetic resources for several traits. Indeed, by SDS-PAGE, a low diversity was shown among genotypes used at Glu-A1 locus, confirming the dominance of (c) allele, however Glu-B1 present a high diversity with the superiority of (b) and (e) alleles. Based on mixing time (MT) and bandwidth at peak dough resistance (BWPDR) values, Mixograph test indicated a mean score of 6.5 suggesting a good bread making ability of Algerian durum wheat. In fact, Ofanto, Mexicali75, Vitron, Chen’s and Saoura held the top of the rank scoring a value of 8, followed by Hedba03, Simeto and Marzak (used as check) showing a score of 7.5. This is due to the presence in their flours a high gluten strength according to the test of SDS sedimentation. These results are very motivating to be used in local durum wheat improvement program.
The stinging nettle (Urtica dioïca L.) has been used as a traditional remedy to treat an important range of diseases due to its therapeutic virtues. This work was undertaken to valorize the ...prospective of extracts of wild Urtica dioica of Algeria as sources of polyphenols and natural antioxidants, as well as the effectiveness of diverse extraction techniques (Soxhlet and maceration) and solvents (ethanol and hexane) on the content of secondary metabolites, and their antioxidant activity were examined by Folin-Ciocalteu, DPPH, FRAP and TAC essays, respectively. The phytochemical screening of aerial part of Urtica dioïca revealed the presence of bioactive compounds: flavonoids, phenols, tannins, anthocyanins and saponosides. Soxhlet with ethanol extracts of Urtica dioica indicated the highest values of total phenolic (13.35 ± 1.06 mg GAE / g DW), flavonoids (3.61 ± 0.46 mg QE / g DW), and tannin (5.37 ± 0.59 mg CE / g DW). Similarly, In terms of IC50, the results clearly showed that the technique of Soxhlet with ethanol was the strongest radical scavenger (0.343 ± 0.012 mg/ml). On another hand, maceration with hexane extracts represented the lowest contents of polyphenols compounds and the antioxidant activity. Subsequently, Soxhlet associated with ethanol exhibited the highest extraction ability for isolation of bioactive ingredients from wild Urtica dioica.
In the present study, we are interested to investigate the biological activities and nutritive values of Limoniastrum guyonianum leaves and stems. Chemical analysis showed that the most abundant ...constituent of the volatile fractions identified was the camphor. The evaluation of the antioxidant activities demonstrated great differences depending on the tested organ. Indeed, methanolic leaves extract was more effective to inhibit DPPH radical and to reduce Fe3+. However, stems extract exhibited the highest radical scavenging of ABTS+. Stems and leaves extracts showed similar antibacterial effects against E. coli, S. aureus, and E. faecalis (MIC = 0.156, 3.12 and 0.156 mg/mL, respectively). Stems extract was the best inhibitor of P. aeruginosa growth (MIC = 0.156 mg/mL). The nutritive values showed that leaves and flowers contained the highest levels of protein that varying between 11.55 % for leaves and 12.6 % for flowers. The lipid content ranged from 14.2 0% for leaves and 12.66 % for flowers. This species can have economic potentiality and may be developed as forage for animals or industrial ingredients for various uses in cosmetic and alimentary industries.
Selection for higher yield and wider adaptability are the most important tasks in crop breeding programs. (GE) interactions are commonly seen as one of the major barriers in plant breeding. The ...present work aims to assess the effects of GE interaction for the grain yield of 14 durum wheat varieties grown in rain-fed environments during 2014-2017 cropping seasons, and to analyze the relationships between 15 traits intra and inter-environments. Field trials were carried out in a randomized complete block design with four replicates. Grain yield data were analyzed using AMMI model. The combined analysis of variance showed that the effects of genotype, environment and their interactions were highly significant on the grain yield. Using CV and Pi index, GTA dur was the high yielding (32.5 q ha-1) and most stable variety across all the environments. Based on the inter-character correlation, the indirect selection of grain yield via the number of grains per m2 would be effective. Moreover, the inter-environment correlation of the studied variables confirms there was GE interaction and suggests that the best varieties should be chosen according to their specific adaptation. Cold environments differed from warm and moderate ones in the ranking of varieties. Indeed, Sétif site offers better possibilities for producing the Ofanto variety (39.9 q ha-1). Whereas, GTA dur and Simeto (30.9 q ha-1 and 29.7 q ha-1, respectively) prove to be the most efficient in terms of grain yield at Oued Smar and Khemis Miliana sites together.
Several species of Eucalyptus are used in folk medicine as an antiseptic, anti-inflammatory, and against respiratory infections, such as colds, sinus congestion and influenza. These species have ...shown potential antioxidant properties in addition to antimicrobial activities. In the present paper, we were interested in Eucalyptus blakelyi Maiden, a species belonging to the Myrtaceae family. Our study can be considered as the first detailed report on the chemical composition, antioxidant and antimicrobial activity of different extracts. The aim of the current study is to evaluate the biological activities of essential oils, methanolic and aqueous extracts of this plant. The present work was realized on leaves collected from National Institute for Forest Research (INRF) of Baïnem (Algiers, Algeria), and the results showed that essential oil's yield obtained by hydrodistillation was 2.13 %. Actually, 15 compounds were identified by GC-MS profile, and the major compound was 1.8-cineole with 62.74 %. Indeed, the antiradical activity using the DPPH method has shown that methanolic and aqueous extracts had an interesting antioxidant ability with an IC
50
of 0.33 and 0.39 mg/ ml respectively. The antimicrobial activity of the essential oil, methanolic and aqueous extracts on eleven microbial strains was evaluated using the aromatogram method. Thus, the methanolic extract proved to be the most active compared to the aqueous extract and the essential oil by inducing a maximum inhibition zones of 19.66 mm for Staphylococcus aureus ATCC29213 and 25.66 mm for Candida albicans. The results suggest potential applications of essential oil in food and extracts in pharmaceutical industry.
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