African Journal of Agriculture

African Journal of Agriculture ISSN 2375-1134 Vol. 6 (1), pp. 001-006, January, 2019. © International Scholars Journals

Full Length Research Paper

Seasonal variations of Cd, Cu, Pb and Zn in the edible mollusc Donax trunculus (Mollusca, Bivalvia) from the gulf of Annaba, Algeria

Hayette Beldi¹, Frédéric Gimbert², Samuel Maas², Renaud Scheifler², Noureddine Soltani¹*

¹Laboratory of Applied Animal Biology Department of Biology, University of Annaba 23000-Annaba, Algeria.

²University of Franche-Comté, Department of Environmental Biology, EA 3184 MR USC INRA, Place Leclerc 25030-Besançon Cedex, France.

Accepted 10 November, 2018

Abstract

Seasonal variations in the concentrations of four trace heavy metals (cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn)) were determined in Donax trunculus (Mollusca, Bivalvia) at two contaminated sites in the gulf of Annaba (East of Algeria): El Battah and Sidi Salem . The average concentrations of the metals exhibited the following order: Zn>Cu> Pb>Cd for the two sites. The statistical analysis revealed a significant effect of seasons for all metals measured, the highest values being recorded in winter for Zn and in summer for the other metals. Contrary to expectation, both sites were contaminated with trace heavy metals analysed. Although the highest levels were detected in Sidi Salem beach, there was no significant difference on trace heavy metal concentrations between sites, except for Cd. The implication of this metal contamination for local population was discussed.

Keywords: Bivalve Molluscs; Donax trunculus; Environmental contamination; Trace heavy metals, Biomonitoring.

Key words: Zooplankters, rotifers, Omi River, Nigeria.

African Journal of Agriculture ISSN 2375-1134 Vol. 6 (1), pp. 001-004, January, 2019. © International Scholars Journals

Full Length Research Paper

Determination of residues of deltaméthrin in wheat and potato by HPLC

Rachdi BOUSSAHEL* ¹ , Khadija M. MOUSSAOUI ² , Djamila HARIK ²

¹H. C. A., Service de Toxicologie, BP 240 Kouba 16050, Algeria.

²Ecole Nationale Polytechnique, El Harrach 16200, Algeria

Accepted 2 November, 2018

Abstract

Residues of deltamethrin, a pyrethroid insecticide commonly used to protect stored grains, have been determined in wheat and potato by high -performance liquid chromatography with UV detection at 233 nm after extraction by chloroform and a silica gel clean-up. Recoveries from fortified samples spiked with 1 ppm of deltamethrin exceeded 75% for both products. The control carried out on imported products showed the presence of this insecticide that sometimes exceeded the maximum limits of residues authorized by the OMS/FAO (0.10 ppm in potatoes and 1.00 in wheat).

Key words: deltamethrin, residues, wheat, potato, HPLC.

African Journal of Agriculture ISSN 2375-1134 Vol. 6 (1), pp. 001-010, January, 2019. © International Scholars Journals

Full Length Research Paper

Impact of acid and oxgall on antibiotic susceptibility of Probiotic Lactobacilli

Ehab Essa Kheadr

Nutraceuticals and Functional Foods Institute (INAF), University of Laval, Quebec, PQ, Canada, G1K 7P4 and Department of Dairy Science and Technology, Faculty of Agriculture, University of Alexandria, Alexandria, Egypt. Current mailing Address: Nutraceuticals and Functional Foods Institute (INAF), University of Laval, Quebec, PQ, Canada, G1K 7P4. E-mail: [email protected].

Accepted 09 November, 2018

Abstract

The present study was conducted to determine the susceptibility of 13 Lactobacillus strains to 14 antibiotics and to evaluate the impact of some gastrointestinal stressful conditions, particularly acid and bile stress, as well as acid adaptation on their antibiogram profiles. The strains tested were 2 of Lactobacillus acidophilus, 1 Lb. delbrueckii subsp. bulgaricus, 2 Lb. casei, 1 Lb. casei paracasei subsp. paracasei, 1 Lb. delbrueckii subsp. lactis, 4 Lb. plantarum and 2 Lb. rhamnosus. In control trails, the majority of the strains tested were susceptible to ampicillin, penicillin, chloramphenicol, erythromycin, novobiocin and nisin A, but resistant to vancomycin, kanamycin, neomycin, paromomycin, streptomycin and nalidixic acid. Lactobacilli strains showed variable susceptibility to cloxacilline and tetracycline. Acid-adaptation (strains adapted to grow at pH 4.0) resulted in increased resistance to cloxacilline, erythromycin and tetracycline, in strain dependent manner. Acid- stressed (exposure to pH 2 for 90 min at 37˚C) lactobacilli appeared to be more resistant to ampicillin, cloxacilline, chloramphenicol and tetracycline compared with un-stressed strains. In the presence of 0.3% (w/v) oxgall, lactobacilli became more susceptible to aminoglycosides and slightly resistant to cell wall-targeted antibiotics. However, oxgall stress (exposure to 0.3% (w/v) oxgall for 90 min at 37˚C) slightly modified antibiogram profile depending on the strain tested. Results reported in this study showed that acid and oxgall stresses could substantially modify antibiotic susceptibility/resistance profile of lactobacilli, which may thus affect their probiotic capacity especially when used along with antibiotics.

Keywords: Probiotics, lactobacilli, antibiotic susceptibility, acid, oxgall.

African Journal of Agriculture ISSN 2375-1134 Vol. 5 (2), pp. 318-330, February, 2018. © International Scholars Journals

Full Length Research Paper

Assessment of microarray analysis of genes affected by salt stress in tomato

*William Bernard¹, Linda Ayers² and Abott Galloway²

¹Institute of Agricultural and Environmental Research, Tennessee State University, 3500 John A Merritt Blvd, Nashville, TN37209, USA.

²Plant Biology Department, University of Minnesota, St Paul, MN 55108. USA.

*Corresponding author. E-mail: [email protected]

Accepted 02 April, 2014

Abstract

Large-scale gene expression affected by salt stress was analyzed with tomato seedlings (Lycoperson esculentum Mill cv. Money Maker) by a cDNA microarray (Tom1). The significantly differentially expressed genes (5% Benjamini-Hochberg false discovery rate) consisted of 1757 sequences in the analyzed tissues (cotyledons + shoot tip). Genes with over 2 fold difference were selected from the list and further categorized into different function and cellular processes. Tomato homologous genes for the chaperone proteins, antioxidant enzymes (catalase and peroxidase), and ion transporters (Na⁺-driven multidrug efflux pump, vacuolar ATPase, and others) were induced. The ACC oxidase and ethylene-responsive gene tomato homologs had higher transcript level after salt treatment. Multiple members with different expression patterns were identified for the bZIP, WRKY, and MADS-box transcription regulator. Different genes in the signal transduction pathway, such as the protein kinases (Shaggy kinase, mitogen-activated protein kinase, ethylene receptor neverripe, and others), protein phosphatases, calmodulin, G -protein, and the N - myristoyltransferase were regulated by salt stress. Most of the protease and the inhibitor homologs were suppressed by salt stress. In addition, different isoforms of cytochrome P450, genes for polyamine biosynthesis (putrescine and proline) and detoxification compounds (glutathione and thioredoxin), several key enzyme genes in the metabolic pathways of carbohydrates, amino acids, and fatty acids, were also affected by salt treatment. This study has provided a set of candidate genes, especially those in the regulatory machinery that can be further investigated to define salt stress in tomato and other plant species.

Key words: Antioxidants, cellular metabolism, cell wall, chaperonine, ethylene, protein kinase, tomato, transcription regulator, translation regulator, salt stress.