Annona muricata: An alternate mosquito control agent with special reference to inhibition of detoxifying enzymes in Aedes aegypti.

This study was aimed to investigate an effectual level of Annona muricata (soursop) extracts on mosquito vectors namely, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. The toxicity study on non-target organism and other important biochemical marker enzymes to find and illustrate the exact mechanism of specific enzymes responsible for detoxifying allelochemicals. Among the various soursop seed kernel extracts tested for larvicidal activity, the 0.9% saline extract exhibited maximum mortality (100%) against three vectors at the lowest concentration for 24 h exposure. Based on these findings, the saline extract was opted for further studies including toxicity on non-target organism and systemic effects on important biochemical constituents in the larvae A. aegypti at the lethal threshold time (18 h) with LC50 concentration (0.009 mg/mL). The tested extract against non-target aquatic fourth instar larvae Chironomus costatus was safe up to 0.0028 mg/mL for 24 h exposure and the mortality was observed only above the concentration 0.0028 mg/mL used in the study. The systemic effects on main neuron transmitter Acetylcholinesterase (p ≤ 0.01), xenobiotics detoxifying enzyme of α-and ß-carboxylesterase (p ≤ 0.05; p ≤ 0.01) and antioxidant enzyme glutathione S-transferase (p ≤ 0.05) were reduced significantly in quantitative analysis. Analysis of such biochemical constituents of proteins and enzymes α-and ß-carboxylesterase were considerably down regulated in the resolving native-PAGE. In contrast, acid and alkaline phosphatase were upregulated in both quantitative and qualitative analysis. This investigation clearly demonstrates the soursop extract has potent larvicidal agent with alterations in biochemical constituents of exposed larvae of A. aegypti.

Green synthesis of silver-nanoparticles from Annona reticulata leaves aqueous extract and its mosquito larvicidal and anti-microbial activity on human pathogens.

Silver nanoparticles play a important role in controlling mosquito population as well as multi drug resistant pathogens without causing much harm to humans. In the present study was focused on green synthesis of silver nanoparticles against dengue causing vector (Aedes aegypti) and pathogens affecting humans. The synthesized silver nanoparticle was confirmed using UV- absorption spectrum range obtained at 416 nm, XRD, FTIR and HR-TEM analysis were used to determine the silver nanoparticle morphology and size with ∼6.48 ± 1.2-8.13 ± 0.18 nm and face centered cubic structure. The synthesized silver nanoparticles were exposed to fourth instar larvae of A. aegypti with different concentration (3-20 µg/mL) for 24 h and its elicit maximum mortality (100%) at their final concentration of 20 µg/mL and it's LC50 value was 4.43 µg/mL and LC90 value was 13.96 µg/mL, respectively. The minimum inhibitory activities of the tested pathogens were 125, 31.25, 62.5, 62.6 and 62.5 µg/mL for the Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans respectively. Further, the synthesized silver nanoparticle shows a potent antimicrobial activity against all tested pathogens. Moreover the effect of silver nanoparticle against Red Blood Cells belonging to 'O' positive blood group were tested and does not cause higher hemolysis to the cells even at the highest concentration. Based on these finding, we strongly suggested that face centered cubic structured A. reticulata AgNPs is an eco-friendly and potent bio-medical agent and can be apply in wide range of application an alternative chemically synthesized metal nanoparticle.

Indirubin-3-monooxime induced cell cycle arrest and apoptosis in Hep-2 human laryngeal carcinoma cells.

The commercially available analogue of indirubin, indirubin-3-oxime, is known for its antitumor activities. To further establish its role in anticancer activity, we tested its potential against human laryngeal carcinoma cell line (Hep-2). We investigated the molecular mechanisms of indirubin-induced apoptosis and growth arrest in human laryngeal carcinoma cells. Upon treatment with indirubin-3-monooxime, a time dependent inhibition of cell growth was observed and cells developed many hallmark features of apoptosis. The increase of chromatin condensation after treatment with indirubin-3-oxime identified by staining with chromatin stain Hoechst 333258 indicates apoptosis. The observed increase in DNA fragmentation after indirubin-3-oxime in DNA gel electrophoresis indicates the apoptotic feature exhibited by the drug. Flow cytometric analysis confirmed that indirubin increased populations of apoptotic phase G1. Indirubin-3-oxime-induced growth inhibition was associated with induction of Cdk inhibitor p21, inhibition of cyclin D1 and activation of caspase-3. We conclude that indirubin-3-oxime induces cell death and apoptosis in human laryngeal carcinoma cells.