#lc50

This study aimed to evaluate the presence of bioactive compounds in Homalocladium platycladum (Tapeworm plant) through bioactivity screening and toxicity assessment. The powdered mature stems of the plant were extracted using different solvents, namely n-hexane (HEX), dichloromethane (DCM), ethyl acetate (ETA), n-butanol (BUT), and methanol-water (WAT). The resulting fractions were prepared and tested at various concentrations using the brine shrimp lethality assay. The results indicated that the HEX, DCM, and BUT fractions exhibited immediate and acute toxicity, suggesting the presence of bioactive compounds. Furthermore, all fractions demonstrated toxicity at longer exposure times, indicating the potential for chronic toxicity. The median lethal concentration (LC50) analysis using the Miller-Tainter method revealed moderate toxicity for the HEX and DCM fractions, with LC50 values of 199.9 ppm and 457.3 ppm, respectively. Moreover, all fractions, including HEX, DCM, ETA, BUT, and WAT, exhibited bioactivity potential at longer exposure times, with calculated LC50 values of 19.79 ppm, 38.82 ppm, 14.77 ppm, 5.565 ppm, and 131.3 ppm, respectively. Notably, all fractions, except for the methanol-water fraction, displayed high toxicity after 24-hour exposure. These findings suggest that the Tapeworm plant contains bioactive compounds with pharmacological potential. Therefore, further investigation of these compounds is warranted for the development of novel pharmaceutical agents.

Microtermes obesi belong to one such new clad of termite species which damages tea plantations of Darjeeling foothills. To control tea pests, planters use synthetic insecticides that have lead to the much bigger problem of insecticide tolerance in many tea pests. Present study contemplates to investigate the tolerance status of the pest species, collected from organically and conventionally managed tea plantations of Darjeeling foothills to three different commonly used insecticides – Imidacloprid 17.8% SL, Cypermethrin 35% EC and Chlorpyrifos 20% EC, along with the activity of the three major detoxifying enzymes, General Esterases(GE), Glutathion S Transferase (GST) and Cytochrome oxydases (CYP450). Results obtained showed higher level of mean lethal concentration (LC50) for Imidacloprid 17.8% SL = 63.66 ppm, Cypermethrin 35% EC = 31.99 ppm, and Chlorpyrifos 20% EC = 18.57 ppm in M. obesi population collected from conventionally managed tea plantations, as compared to that from organically managed plantations. Even observations on detoxifying enzymes reflected a corresponding enhancement in their activities which were noted as: GE = 2.25 mM mg -1 protein; GST = 120.86 µM min-1 mg-1 protein; CYP450 = 0.75 n mol min-1 mg protein-1 in population of pesticide managed conventional plantation, and at a lower level (GE = 0.23 mM mg -1 protein; GST = 16.73 µM min-1 mg-1 protein; CYP450 = 0.26 n mol min-1 mg protein-1) in population of organically managed tea plantation. Hence, developing an enzyme-based marker for M. obesi populations may be of practical use in titrating an effective pesticide dosage under IPM/IRM strategies.

This study aimed to evaluate the presence of bioactive compounds in Homalocladium platycladum (Tapeworm plant) through bioactivity screening and toxicity assessment. The powdered mature stems of the plant were extracted using different solvents, namely n-hexane (HEX), dichloromethane (DCM), ethyl acetate (ETA), n-butanol (BUT), and methanol-water (WAT). The resulting fractions were prepared and tested at various concentrations using the brine shrimp lethality assay. The results indicated that the HEX, DCM, and BUT fractions exhibited immediate and acute toxicity, suggesting the presence of bioactive compounds. Furthermore, all fractions demonstrated toxicity at longer exposure times, indicating the potential for chronic toxicity. The median lethal concentration (LC50) analysis using the Miller-Tainter method revealed moderate toxicity for the HEX and DCM fractions, with LC50 values of 199.9 ppm and 457.3 ppm, respectively. Moreover, all fractions, including HEX, DCM, ETA, BUT, and WAT, exhibited bioactivity potential at longer exposure times, with calculated LC50 values of 19.79 ppm, 38.82 ppm, 14.77 ppm, 5.565 ppm, and 131.3 ppm, respectively. Notably, all fractions, except for the methanol-water fraction, displayed high toxicity after 24-hour exposure. These findings suggest that the Tapeworm plant contains bioactive compounds with pharmacological potential. Therefore, further investigation of these compounds is warranted for the development of novel pharmaceutical agents.