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The objective of this work is to investigate the insecticidal activity of Vitex agnus castus (VAC; Lamiales: Lamiaceae) essential oils and organic extracts against the species Ceratitis capitata L. adults (Diptera: Tephritidae). Extraction of the essential oils from the leaves and seeds of the plant was carried out using hydrodistillation while organic extracts were obtained using the Soxhlet apparatus. The principal compounds of essential oils were 1, 8-cineol, a-pinene, ß-farnesene and ß-caryophyllène for leaves and 1, 8-cineole, sabinene, a-pinene, and ß-farnesene for seeds. The insecticidal activity was determined by evaluating the adulticidal effect using direct contact application methods. Our extracts from leaves and seeds of VAC presented toxicity in Ceratitis capitata adults. Responses varied based on the type of extract, plant part, and exposure time. The good insecticidal activity was achieved by essential oils from leaves and seeds. The lethal concentration values (LC50) were 0.660 mg mL-1 and 6.170 mg mL-1 after 24 h of incubation respectively. Thus, the essential oils from The VAC leaves and seeds exhibited insecticidal activity in Ceratitis capitata and can be used as an alternative to the control of these dipterans. Organic extracts from The VAC leaves and seeds showed moderate insecticidal activity against Ceratitis capitata after a long time of incubation. Prospective studies of these oils are needed on cytotoxicity, mutagenicity, and genotoxicity in human cells, in addition to the in vitro safety of these essential oils in human cells for safe use. [ABSTRACT FROM AUTHOR]

Introduction: Most recurrently available organic solvents are toxic and inflammable and pose high risks to human health. Natural deep eutectic solvents (NADESs) have been developed as promising green alternatives. Objective: We aimed to extract polyphenolic compounds from Mentha pulegium using lactic acid‐based deep eutectic solvents. Extraction parameters were optimized by response surface methodology. Material and Methods: Combined with ultrasound‐assisted extraction, three different lactic acid‐based deep eutectic solvents were investigated for the extraction of polyphenols. Methanol (80%, v/v) was used for comparison. The optimized influencing factors were: water content in solvent, extraction time, and temperature. The design was adopted including 17 experiments with three center points. Results: All NADESs tested showed an excellent extraction efficacy compared to 80% methanol. Under the optimized conditions, with 45% of water, at 30°C, and for extraction 90 min, the highest extraction yields were recorded using lactic acid:sodium acetate (3:1), achieving 173.35 ± 0.02 mg gallic acid equivalents (GAE)/g dry weight (dw) of polyphenols and 95 ± 0.09% antioxidant activity. After extraction for 90 min at 80°C with 18% of water, we obtained 164.06 ± 0.01 mg GAE/g dw and 94 ± 0.02% antioxidant activity using lactic acid:glucose (5:1). Efficient recovery (64.92 ± 0.01 mg GAE/g dw and 97 ± 0.1% antioxidant activity) was achieved using lactic acid:glycine (3:1) with 31% of water, at 35°C, and extraction for 30 min. Conclusion: Our results indicate that with optimized parameters, the proposed natural solvents are excellent alternatives to chemical ones for the extraction of phenolic compounds. Combined with ultrasonic‐assisted extraction, three different lactic acid‐based deep eutectic systems were investigated to extract polyphenolic compounds from Mentha pulegium. The influencing factors optimized were water content in solvent, extraction time, and temperature. The design was adopted including 17 experiments with three center points. Our data illustrate that all natural deep eutectic solvents (NADESs) tested have an excellent efficacy of extraction compared with methanol 80%, ranging under specified extraction conditions from 164.06 to 173.35 mg GAE/g dw, with an excellent antioxidant activity achieving over 90%. [ABSTRACT FROM AUTHOR]

The present work aims to isolate actinomycete bacteria with antagonistic abilities towards Botrytis cinerea, the causal agent of gray mold, from a soil sample collected from the rhizosphere of a healthy tomato grove. In vitro confrontation led to the isolation of 104 actinomycete isolates; fifteen isolates have shown the most significant mortality rate of the mycelial growth of B. cinerea (>50%). Based on the results of this screening, representative strains were selected to verify their in vivo antagonistic activity on tomato fruits; the reduction of B. cinerea has a percentage ranging from 52.38% to 96.19%. Furthermore, the actinomycete isolates were evaluated for their plant growth-promoting (PGP) properties and their ability to produce biocontrol-related extracellular enzymes viz., amylase, protease, cellulase, chitinase, esterases, and lecithinase. Indeed, Ac70 showed high β-1,3-glucanase activity and siderophore production (17U/ml and 43% respectively), and the highest chitinase activity (39μmol/ml) was observed for Ac24. These results indicated that these actinomycetes might potentially control gray mold caused by B. cinerea on tomato fruits. Investigations on enhancing the efficacy and survival of the biocontrol agent in planta and finding out the best formulation are recommended for future research. [ABSTRACT FROM AUTHOR]

Plants are often subject to attack by fungi, nematodes and insects, which generate immense yield losses. Hence, the quest for crop protection solutions is ongoing, concurrent with greater awareness towards the use of synthetic chemicals in agricultural practice. Scientific research has shifted towards the use of natural products, which possess good efficacy and are environment friendly. This review details two classes of natural products. The first one is the plant essential oils with their volatile constituents, which have been proven to possess antifungal, nematicidal and insecticidal activities. The second class is the lipopeptides produced by antagonistic microorganisms. Their biological activities are discussed, as they have been shown effective against plant fungi and pests. Essential oils and lipopeptides have huge potential to be used as biopesticides. The combinatorial approach between essential oils, antagonistic microorganisms and lipopeptides for crop protection is discussed, potentially both can produce a synergistic effect, resulting from their combination against plant fungi, nematodes and pests. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite (Tetranychus urticae Koch) is an important pest of many horticultural crops. A study was conducted to evaluate the effect of three fluorescent Pseudomonas isolates obtained from rhizospheric soil of tomato (Solanum lycopersicon) in Agadir, Morocco: Q110B, Q036B and Q172B, as potential biological control agents for T. urticae. Both acaricide and repellent activities were assessed on homogenous adult mites. The acaricidal activity test evaluated five concentrations of bacterial suspensions: 0 (control), 102, 104, 106, 108, and 1010 cfu · ml-1, while only the 1010 cfu · ml-1 concentration of each bacterium was used for the repellent bioassay. The mortality rate and repellentindex were recorded 24, 48 and 72 h after application. Results indicated that the survival rate of T. urticae was reduced (p = 0.01) by all three bacterial isolates compared to control. Within the 24-72 h time period the mortality rates ranged from 8 to 87%, 16 to 99%, and 13 to 89%, for Q110B, Q036B and Q172B isolates, respectively. The isolate Q036B (LC50 = 0.598 cfu · ml-1) provided higher mortality rates than Q172B and Q110B with LC50 values of 90,846 and 169,585 cfu · ml-1, respectively. Repellent activity was also the highest with Pseudomonas Q036B having a 71% repellence index at 48 h after application. Regarding the mechanism of action, all three isolates produced hydrogen cyanide, and exhibited protease and cellulose activities, although only Q036B and Q172B had potential chitinase action. Identification analysis showed that the isolates were either Pseudomonas putida (Q172B) or P. fluorescens (Q110B and Q036B). Our results indicate that the P. fluorescens isolate Q036B is a promising candidate for biological control of T. urticae, and has potential to contribute to an integrated pest management program to control this important pest. Then the fruits produced will be qualified as safe for consumers and the environment. The present work was customized to give support for policy decision makers as an agroecological potential meeting needs of industries and ecological balance. [ABSTRACT FROM AUTHOR]

Thymus satureioides (TS) oil was hydrodistillated and analyzed by chromatography. The natural oil was tested as a green inhibitor for tinplate in 0.5 M HCl solution. Electrochemical parameters of different concentrations of TS oil and the corresponding corrosion inhibition efficiencies were reported. Polarization data indicated that the studied oil acts as a mixed type inhibitor without changing the mechanism of hydrogen evolution reaction. The effect of temperature (25-60°C) on the inhibition efficiency at different concentrations of the oil studied was investigated. The data revealed that the TS oil might exhibit good inhibition even at moderate to high temperatures. The corrosion activation parameters (Ea, ΔH*, ΔS*, and ΔG*) were estimated and discussed. It was found that the Ea values for tinplate corrosion in the inhibited solutions were higher than that for the uninhibited solution, indicating good inhibitor characteristics with a physical adsorption mechanism. [ABSTRACT FROM AUTHOR]

This study deals with the physico-chemical characterization of wastewaters from the fish industry in Agadir city, Morocco. Seven samples were collected at every two hours from 8 a.m until 8 p.m. Three samplings were carried in this study accordingly: the first, on November 23rd, 2005; the second, on February 23rd 2006 and the last one, on June 23rd, 2006. The results indicated that the effluents show great variations in terms of conductivity (3.36-96.3 mS/cm) and temperature (17-35 °C). The wastewaters were generally characterized by high amounts of chlorides, with average values of 9951.8 mg.L-1, and had BOD5 values between 1500-20500 mg.L-1, as well as COD values between 3500-26000 mg.L-1. Additionally, high amounts of total phosphor (total P), ammonium nitrogen (N-NH4), and total suspended solids (TSS) were observed. From the overall results, it can be said that the wastewaters from fish industry constitute a major environmental problem and must be taken into careful consideration. [ABSTRACT FROM AUTHOR]