LABORATORY INVESTIGATION OF TERMINALIA ARJUNA AND TRACHYSPERMUM ROXBURGHIANUM AGAINST GROUNDNUT PEST, HELICOVERPA ARMIGERA

ABSTRACTObjective: The present study was investigated important medicinal plant extract Terminalia arjuna and Trachyspermum roxburghianum against thefourth instars larvae of groundnut pest Helicoverpa armigera.Methods: The extracts were used as methanol, ethyl acetate, chloroform, and hexane and are used as the different concentration of 25, 75, 125, 175,and 225 ppm level of antifeedant, larvicidal, and ovicidal activity of fourth instars larvae on H. armigera were maintained the laboratory condition.Results: It was noted that antifeedant activity of two important medicinal plants in the experiment of the methanol extract of T. arjuna was 99% at225 ppm and T. roxburghianum methanol extract was 92% at 225 ppm, respectively. The high percent mortality present in the 225 ppm concentrationof both plants are T. arjuna: 100, 98, 90, and 86 ppm and T. roxburghianum: 97, 92, 89, and 82 ppm, respectively. These processes maintainedprobit analysis, values are detecting and high mortality level of methanol extract T. arjuna with LC50 and LC values were 105.81 and 202.80 ppm;T. roxburghianum methanol extract of LC50 and LC9090 values were 91.94 and 177.48 ppm, respectively. The maintained in the treatments based on theprocedure followed the experiment of ovicidal activity of both plants. The eggs are no hatchability for methanol extract of T. arjuna were 91% at225 ppm, respectively, and methanol extract of T. roxburghianum were 90% at 225 ppm, respectively.Conclusion: These results have been suggested that the T. arjuna and T. roxburghianum plant methanol extract used as the integral pest managementstudies of the groundnut pest, H. armigera.Keywords: Antifeedant, Larvicidal, Ovicidal activity, Terminalia arjuna, Trachyspermum roxburghianum, Helicoverpa armigera

A marine cryptochrome with an inverse photo-oligomerization mechanism

Abstract Cryptochromes (CRYs) are a structurally conserved but functionally diverse family of proteins that can confer unique sensory properties to organisms. In the marine bristle worm Platynereis dumerilii, its light receptive cryptochrome L-CRY (PdLCry) allows the animal to discriminate between sunlight and moonlight, an important requirement for synchronizing its lunar cycle-dependent mass spawning. Using cryo-electron microscopy, we show that in the dark, PdLCry adopts a dimer arrangement observed neither in plant nor insect CRYs. Intense illumination disassembles the dimer into monomers. Structural and functional data suggest a mechanistic coupling between the light-sensing flavin adenine dinucleotide chromophore, the dimer interface, and the C-terminal tail helix, with a likely involvement of the phosphate binding loop. Taken together, our work establishes PdLCry as a CRY protein with inverse photo-oligomerization with respect to plant CRYs, and provides molecular insights into how this protein might help discriminating the different light intensities associated with sunlight and moonlight

Purification of PaTx-II from the venom of Australian King Brown Snake and characterization of its antimicrobial and wound healing activities

Infections caused by multi-drug-resistant (MDR) bacteria are a global threat to human health. As venoms are the source of biochemically diverse bioactive proteins and peptides, we investigated the antimicrobial activity and murine skin infection model-based wound healing efficacy of a 13 kDa protein. The active component PaTx-II was isolated from the venom of Pseudechis australis (Australian King Brown or Mulga Snake). PaTx-II inhibited the growth of Gram-positive bacteria in vitro, with moderate potency (MICs of 25 µM) observed against S. aureus, E. aerogenes, and P. vulgaris. The antibiotic activity of PaTx-II was associated with disruption of membrane integrity, pore formation and lysis of bacterial cells, as evidenced by scanning and transmission micros-copy. However, these effects were not observed with mammalian cells, and PaTx-II exhibited minimal cytotoxicity (CC50 > 1000 µM) toward skin/lung cells. Antimicrobial efficacy was then determined using a murine model of S. aureus skin infection. Topical application of PaTx-II (0.5 mg/kg) cleared S. aureus with concomitant increased vascularization and re-epithelialization promoting wound healing. As small proteins and peptides can possess immunomodulatory ef-fects to enhance microbial clearance, cytokines and collagen from the wound tissue samples were analyzed by immunoblots and immunoassays. The amounts of type I collagen in PaTx-II treated sites were elevated compared to the vehicle controls, suggesting a potential role for collagen in fa-cilitating the maturation of the dermal matrix during wound healing. Levels of proinflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), cy-clooxygenase-2 (COX-2) and interleukin-10 (IL-10), factors known to promote neovasculariza-tion, were substantially reduced by PaTx-II treatment. Further studies that characterize the con-tributions towards efficacy imparted by in vitro antimicrobial and immunomodulatory activity with PaTx-II are warranted