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Rhyzopertha dominica (F.) is considered as a major stored product pest. Conventional insecticides induce adverse effects on the environment. Plant derivative products constitute a promising alternative for pest control. The purpose of our research was to identify the chemical profile of essential oil (EO) extracted from Schinus molle L. (Anacardiaceae) and to evaluate the fumigant and the contact toxicity, and the repellent activity of this oil on adults of Rhyzopertha dominica F. (Coleoptera), a major pest in products that are stored around the world. The effects of this oil were examined on biochemical profile (energy reserves and Proteins), selective biomarkers like acetylcholinesterase (AChE), glutathione S-transferases (GST) and glutathione (GSH), and nucleic acids (DNA and RNA). Digestive enzymes were also investigated. The major chemical compounds identified by the GC-MS were α-phellandrene (16.613%), ß-phellandrene (12.104%), elemol (9.028%) and β-eudesmol (5.872%). Then, we evaluated the repellent activity, and also the effects in nutritional reserves and some biomarkers. This EO exhibited an insecticidal and repellent activity as a function of the exposure time and concentrations. Contact (LC50 at 24 h: 19.99 μL/mL) is the most effective mode of application compared to fumigation (LC50 at 24h: 174.30 μL/L air). S. molle EO was also investigated in digestive enzymes' activities (α-amylase, lipase, chitinase and protease). Our results revealed a decrease in both α-amylase, lipase, protease and chitinase activities in treated adults compared to controls. In addition, we noticed a neurotoxic activity of S. molle EO traduced by a decrease of AChE. An induction of the detoxification system was observed via a decrease in GSH rate and an increase in GST activity. Moreover, the treatment induces an alteration of biochemical profile of R. dominica adults. Lastly, essential oil was examined on nucleic acids. Results showed an increase in DNA and RNA amount in treated adults when compared with control. Due to their effective source of bioactive compounds, the EO from the studied plant could be used as an alternative strategy for the management of stored product pests. [ABSTRACT FROM AUTHOR]

Cadmium is a non-essential heavy metal in the biological system. In this study, we have highlighted to evaluate of the effect toxicity of cadmium chloride (CdCl2) against Marine Bivalve Donax trunculus L. (Mollusca, Bivalvia) under laboratory conditions. The acute bioassay tests at various gradient concentrations of cadmium (5, 7.6, and 10 mg/L) were performed to estimate lethal concentrations 50 (LC50 Concentration estimated that produces a 50% mortality in a test population over a specific period) and 90 (LC90) for 24, 48, 72, and 96 hours of exposure. 96h-LC50 and 96h-LC90 values are: 2.59 and 9.25 mg/L respectively. In addition, the sublethal concentrations (LC10 and LC25) at acute exposure (96 h) which are: 0.72 mg/L and 1.32 mg/L respectively, and their fiducial limits were investigated. The results obtained indicate that cadmium causes mortality in the species studied with a Concentration-response relationship. Thus, specimens of this marine bivalve were experimentally exposed to CdCl2 at concentrations corresponding to 96h-LC10 and 96h-LC50, to evaluate the effect of toxicity on catalase (CAT) and acetylcholinesterase (AChE) activities, followed by a recovery period during 4 days. Results showed that Cd inhibited AChE activity suggesting neurotoxicity disturbances. In addition, we observed a stimulation of the detoxification system as shown by an increase in catalase activity. Additionally, the transfer of individuals exposed to CdCl2 in untreated water showed a gradual restoration of the initial state. The data obtained from this study will provide useful information for understanding the toxicological process of CdCl2 in Donax trunculus. [ABSTRACT FROM AUTHOR]

Biological control is a means of preserving biodiversity and eradicating vector species of diseases such as Anopheles, which cause Malaria. The freshwater fish Gambusia affinis has been introduced into rivers around the world to control Culex larvae. This study aims to evaluate the responses of G. affinis from different sites due to their proximity to polluting sources by measuring growth (total height and weight), metric indices:gonadal-somatic index (GSI), hepato-somatic index (HSI) and condition index (K). It, also, investigated the response of two biomarkers: glutathion-S-transferase (GST) in the liver and acetylcholinesterase (AChE) in the head of adults females and males of G. affinis (Cyprinodontiforme: Poeciliidae). The species was collected during the reproduction period (sexual activity) in three sites different by their level of exposure to pollution sources: Messida River, a reference site located in a protected area, and two other site near to anthropogenic activities, El Karma and Sidi Brahim. The results obtained reveal that the Messida river site shows a better growth with the highest GSI and K compared to the other study sites. The data of the HSI revealed lower values at the same site. Biomarker measurements revealed higher GST induction, AChE inhibition, and a level higher MT at the Sidi Brahim. We conclude that the Sidi Brahim site is the most polluted followed by El Karma and finally the Messida River. The study of the different parameters in the two sexes revealed that the females of G. affinis were more robust than the males. [ABSTRACT FROM AUTHOR]

Biopesticides from botanicals are nowadays strongly encouraged for use in the program of controlling insect vectors of diseases and other harmful insects. The present study had the objective of determining the chemical composition of the essential oil of Mentha x piperita L. (Lamiaceae). We also evaluated the larvicidal and ovicidal activities of EO against Culex pipiens L. according to the World Health Organization (WHO) protocol. The chemical composition of EO from the aerial parts of peppermint was analyzed by gas chromatography-mass spectrometry GC/MS. The main components were menthol (28.66 %), limonene (19.01 %), and p-cymene (15.82 %). Also, this research found that M. x piperita EO showed larvicidal activity against fourth-instar larvae. Mortalities were recorded after 24, 48, and 72 h of treatment. It has potent larvicidal activity with increasing concentration and exposure time (LC50 values were 448.74; 181.97 and 152.05 ppm). Besides, EO showed excellent ovicidal activity, the results of which indicated that the hatchability of eggs treated with LC50 and LC25 is 18.13 % and 53.67 %, respectively. Furthermore, the study examines the efficacy of this oil on the glutathione S-transferase (GST) and acetylcholinesterase (AChE) activity of Cx. pipiens larvae treated with LC50 and LC90. This experiment has led to neurotoxic activity and stimulation of the detoxification system, as shown by AChE inhibition and GST induction respectively. In conclusion, M. x piperita EO is a natural larvicide and promising ovicide against Cx. pipiens. Therefore, it is recommended for use as a natural biocide in the implementation of effective mosquito control programs. [ABSTRACT FROM AUTHOR]

The dry aerial part of Rosmarinus officinalis, collected from Djebel Belkfif (Tébessa, North- Eastern, Algeria), were hydrodistilled in a Clevenger type apparatus and analyzed by GC and GC-MS. The larvicidal activity of the R. officinalis essential oil (EO) against the fourth instar larvae of Culex pipiens L. was determined after 24 hours of exposure according to the World Health Organization procedure. The R. officinalis EO effects, via application of two lethal concentrations (LC25 and LC50), were examined on morphometric parameters (weight and body volume) and main biochemical components (proteins, lipids, carbohydrates) at different exposure periods. Furthermore, glutathione-S-transferase (GST) activity and glutathione (GSH) rate were assessed as biomarkers of the detoxification system. The GC and GC-MS analysis led to the identification of 36 components representing 99.97 % of the total oil, in 1.9 % yield, with 1,8-cineole (44.34 %), camphor (16.74 %), α-pinene (10.07 %) and borneol (5.02 %) as the main components. Bioassay test revealed that R. Officinalis EO exhibited a larvicidal activity against fourth instar larvae at 24 hours (LC25, LC50 and LC90 values were 39.47, 51.33 and 86.77 ppm, respectively). When applied to its LC25 and LC50, EO induced a significant decrease of larvae morphometric parameters and disturbed energy reserves with a marked lipid decrease at different periods. Also, treatment-induced stimulation of the detoxification system is highlighted by GST activity increase and GSH level decrease. [ABSTRACT FROM AUTHOR]

Previous works has shown that the heavy metal pollution is major in the region of Annaba (Northeast Algeria). The aim of this study was to assess the impact of anthropogenic activities on soil quality using Lumbricus terrestris as a bioindicator. Soil samples and earthworms were collected during the autumn and spring at two sites: Sidi Amar located near to several industrial factories, while El Tarf situated in a rural area far from any anthropogenic contamination. The activities of glutathione S-transferase (GST) and acetylcholinesterase (AChE), biomarkers of oxidative stress and neurotoxicity, respectively were measured in earthmorms. The concentrations of heavy metals (Pb, Zn, Mn, and Fe) in soils and earthworm tissues were analyzed using atomic absorption spectrophotometry. The GST and AChE activities and the heavy metal concentrations were found to vary between sites and by season. Marked biomarker responses are noticed during the automn at the site closest to potential sources of pollution. These bioindicative stress response correlated with increasing metal concentration detected in soil and tissue samples. Thus, the difference recorded between the two sites is linked to their level of pollution. while the effect of seasons may be due to rains which promote leaching of heavy metals in soils. L. terrestris could serve as an useful biological indicator of soil contamination. [ABSTRACT FROM AUTHOR]

Actara® 25 WG belongs to neonicotinoids, which is the most widely used insecticide class for controlling various insect pests in the world. The present study was aimed to assess the potential hazards of this insecticide on the mosquitofish Gambusia affinis following a chronic exposure. The female adults were collected during the reproduction period and exposed to various concentrations (10, 20 and 40 mg.L−1) during 28 days. The effect of actara was investigated on morphometric and selected biomarker measurements. Results showed that the compound was found to affect significantly the condition factor at days 21 and 28 of exposure with the highest concentration. However, the treatment had no effect on hepato-somatic and gonado-somatic indices. Biochemical analyses revealed an increase in glutathione S-transferase activity and carbonylated protein content, and a decrease in acetylcholinesterase activity for the three tested concentrations while the vitellin level was reduced only for the highest concentration. Thus, this product can pose side-effects on this non-target freshwater fish. [ABSTRACT FROM AUTHOR]

Our study was aimed to assess the responses of three biomarkers, Acetylcholinesterase (AChE), Glutathi­one S-transferase (GST) and Malondialdehyde (MDA) in various tissues (gonad, mantle, digestive gland) of Donax trunculus (Bivalvia, Donacidae), a Mollusk Bivalve bioindicator of pollution in the Gulf of Annaba (Algeria). The samples were collected during the four seasons (winter, spring, summer, au-tumn) of 2016 year in three sites of Annaba gulf; Sidi Salem, site exposed to various sources of industrial and harbor pollution; Echatt, site subject to urban and agricultural wastes; and El Battah site distant from any source of pollution. The results showed a significant inhibition of AChE and induction of GST and MDA in individuals of Sidi Salem and Echatt as compared to El Battah with significant effects of both site and season. Indeed, the season effect was showed an inhibition of AChE and an induction of GST and MDA more pronounced during summer and spring compared to the other seasons. In addi­tion, the comparison between tissues revealed a more marked response in gonad than mantle and di­gestive gland. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the chemical composition of the leaf essential oil of Thymus vulgaris cultivated in Tebessa (Northeast Algeria) and to evaluate its potential larvicidal activity against fourth instar larvae of Culex pipiens L., 1758. A total of 20 fourth instar larvae of C. pipiens were exposed to a variety of concentrations (25-200 ppm) in laboratory according to the standard procedure portrayed by World Health Organization. The effects were examined on the mortality, the activities of acetylcholinesterase (AChE), glutathione S-transferase (GST), gluhatione (GSH) rate and the biochemical composition (proteins, lipids, carbohydrates) of larvae body, respectively. The EO yield calculated from the dry matter of the aerial part of the plant was 1.58 %. Its chemical composition has been analyzed by the GC and GC-MS systems. A chemical constituent of 18 compounds was identified in the oils of T. vulgaris compounds representing to 99.94 %. Bioassay test revealed that this essential oil exhibited larvicidal properties as they could induce 100 % mortality in the larvae of C. pipiens at the concentrations of 200 ppm. Biomarker measurments in treated larvae (LC25 and LC50) revealed no effect on AChE activity, activation of detoxification system as showed by an increase in GST activity and a decrease in GSH rate. The biochemical compositions show that the essential oil affected the energy reserves with a marked effect on proteins and lipids. Lastly, our results proved the potential use of this natural material as an alternative to synthetic insecticides for controlling mosquitoes. [ABSTRACT FROM AUTHOR]

Objective To evaluate the activity of spiromesifen against the most abundant and investigated mosquito species, Culiseta longiareolata Aitken, 1954 (Diptera, Culicidae). Methods Culiseta longiareolata larvae were collected from untreated areas located at Tébessa (Northeast Algeria). A commercial formulation of spiromesifen (Oberon ® 240 SC) was tested at different concentrations ranging between 238 and 1 428 μg/L on newly molted fourth-instar larvae under standard laboratory conditions according to Word Health Organization recommendations. The effects were examined on the mortality, the morphometric measurements, two biomarkers (catalase and malondialdehyde), and the biochemical composition of larvae, respectively. Results The compound exhibited insecticidal activity. Moreover, it disturbed growth and several morphological aberrations were observed. It also affected body volume, biomarkers and contents of carbohydrates, lipids and proteins. A marked effect on lipids and malondialdehyde was noted, confirming its primary mode of action on lipid synthesis. Conclusions Spiromesifen appears less potent than other insecticides tested such as the insect growth disruptors. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the water quality in the gulf of Annaba in Algeria using selected biomarkers in the edible mollusc Donax trunculus (D. trunculus). The biomarker responses in the mollusc are said to be associated with environmental pollution. Variables measured in D. trunculus are mentioned including seasonal variations of the rate of malondialdehyde (MDA) and the specific activity of specific enzymes. Seasonal variations found in relation to environmental factors are discussed.