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This study aimed to examine the anti-termite potential of four Saharan plant extracts, namely, the apple of Sodom or rubber bush, Calotropis procera; pergularia, Pergularia tomentosa; jimsonweed, Datura stramonium, and Egyptian henbane, Hyoscyamus muticus from Bechar (southwest of Algeria) on workers of the harvester termite, Anacanthotermes ochraceus (Isoptera: Hodotermitidae). A direct contact application test was conducted with five fractions from aqueous extracts of each part of plant species (leaves, stems) using hexane, dichloromethane, ethyl acetate, butanol, and exhausted fraction. A repellent test was realized with aqueous extracts (10%) of plant species leaves and stems. According to the direct contact application test, all tested plants fractions showed termiticidal activities with different degrees. Butanolic fractions presented the best effects from leaves of C. procera and P. tomentosa with median lethal time (LT50) = 231.03 and 244.96 min, respectively. In the second test, wood samples were exposed to termite attack for four weeks, and the weight loss percentage was determined. The weight loss ranged from 0.034 to 16.90% at concentrations of 10% of plant extracts. The best repellent effect was obtained from leaves of C. procera (weight loss = 0.034%) and leaves of D. stramonium (weight loss = 1.29%). It was concluded that some Saharan plants are a good source of anti-termite compounds, especially C. procera. [ABSTRACT FROM AUTHOR]

In this study, Limoniastrum feei extracts were evaluated for management of Fusarium oxysporum f. sp. albedinis (Foa) through antifungal tests and cellulases inhibition (cellulases are cell wall degrading enzymes "CWDE"). Antifungal activity evaluation was realized by direct bioautography. Cellulases inhibition test was realized by contact bioautography. In addition, a phytochemical screening has been done for these extracts on TLC plates (extraction with solvents of increasing polarity: hexane, ethyl acetate, dichloromethane, and methanol). Phytochemical screening was intended to know which metabolite is responsible for the antifungal activity through correlation with antifungal and anti-cellulases effect. The phytochemical study revealed the presence of saponins, flavonoids, tannins, coumarins, and alkaloids in these extracts. The different extracts showed high variability in their phenolic and flavonoids contents as well as antifungal capacity, as the case of ethyl acetate extract. Detection of inhibition zones was revealed with ethanolic Gram's iodine. Inhibition zones were determined as dark brown spots. The results of enzymatic activity -by contact bioautography technique-showed that certain extracts of L. feei present a significant effect on cellulases of Foa. The best effect was presented by methanolic extract of aerial part (inhibition zone diameter in chromatogram is higher than 2 mm). Best antifungal effect was presented by compounds with high probability to be phenolic compounds. [ABSTRACT FROM AUTHOR]

Summary: The present study reports a methodology for the synthesis of symmetrical and unsymmetrical thiourea derivatives 1-9, which have been prepared in good overall yields from condensation reactions between phenylisothiocyanate and different primary amines. The structures of all products were confirmed by the spectroscopic analysis (UV, IR, and NMR). T hese derivatives were tested for anticoagulant activity using PT and APTT reagents, and those reagents are considered also a controller, the results showed that the theN-aryl thiourea derivatives have very high anticoagulant activity. Theoretical calculations based on DFT/B3LYP method have been performed in order to get insights into the molecular geometry and chemical reactivity of the studied compounds. [ABSTRACT FROM AUTHOR]

In this study, the rachis extracts of eight date palm Phoenix dactylifera L. cultivars were analysed by phytochemical screening and bioautography on Fusarium oxysporum f. sp. albedinis (Foa). The choice of cultivars was based on their reaction to Foa (resistant, tolerant and sensitive). Phytochemical screening was realised for flavonoids, tannins, alkaloids and coumarins. Antifungal effects were mostly represented by dichloromethanic extracts (seven out of nine inhibition zones). The best results were represented by the dichloromethanic extract of the cultivar ‘Bent-Cherk’ rachis (6.50 ± 1.41 mm) and the ethyl acetate extract of the cultivar ‘Rotbi’ rachis (6.00 ± 1.41 mm). The date palm cultivars presented some similarities concerning phytochemical screening results related to their resistance or sensibility to Foa. From the correlation between phytochemical screening and bioautography, it was observed that the majority of bioactive compounds against Foa seem to be polyphenols. Thus, the natural defence mechanism in vivo against Foa is probably related to the action of polyphenols. The difference between resistant, tolerant and sensitive cultivars is related to their mechanism of action. [ABSTRACT FROM PUBLISHER]