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The control of Zika virus mosquito vectors and well as the development of drugs in the fight against biofilm-forming microbial pathogens, are timely and important challenges in current bionanoscience. Here we focused on the eco-friendly fabrication of Ag nanostructures using the seed extract of Pedalium murex , an ancient Indian medicinal plant. Initial confirmation of Ag nanoparticles (AgNPs) production was showed by a color change from transparent to dark brown. The UV–Visible spectrum (476 nm), X-ray diffraction peaks (101, 200, 220 and 311) and Fourier transform infrared spectroscopy shed light on the production of green-capped AgNPs. Morphological structure analysis using HR-TEM showed that the AgNPs were mostly hexagonal in shape with rough edges, and a size of 20–30 nm. The larvicidal potential of P . murex seed extract and AgNPs fabricated using the P . murex seed extract ( Pm -AgNPs) was tested on fourth instar mosquito larvae of the Zika virus vector Aedes aegypti . Maximum efficacy was achieved by Pm –AgNPs against Ae . aegypti after 24 h (LC 50 34.88; LC 90 64.56 mg/ml), if compared to the P . murex seed extract. Histopathological analyses showed severe damages to the hindgut and larval muscles in NPs-treated Ae . aegypti larvae. The sub-MIC concentrations of Pm -AgNPs exhibited significant anti-biofilm activity against Gram positive ( Enterococcus faecalis , Staphylococcus aureus ) and Gram negative ( Shigella sonnei , Pseudomonas aeruginosa ) bacterial pathogens, as showed by EPS and MTP assays. Light and CLSM microscopic studies highlighted a significant impact of P . murex seed extract and Pm –synthesized AgNPs on the surface topography and architecture of bacterial biofilm, both in Gram positive and Gram negative species. Overall, results reported here contribute to the development of reliable large-scale protocols for the green fabrication of effective mosquito larvicides and biofilm inhibitors. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is a causative agent of Coronavirus disease-19 (COVID-19), which is considered as a fatal disease for public health apprehension worldwide. This pathogenic virus can present everywhere. As it is a virus it can extend easily and cause severe illness to humans. Hence, an efficient international attentiveness of plan is necessary to cure and prevent. In this review, epidemic outbreak, clinical findings, prevention recommendations of COVID-19 and suggestive medicinal value of south Indian plant sources have been discussed. Though the varieties of improved approaches have been taken in scientific and medicinal concern, we have to pay attention to the medicinal value of the plant-based sources to prevent these types of pandemic diseases. This is one of the suggestive and effective ways to control the spreading of viruses. In the future, it is required to provide medicinal plant-based clinical products (Masks, sanitizers, soap, etc.,) with better techniques by clinicians to contend the scarcity and expose towards the nature-based medicine rather than chemical drugs. This may be a benchmark for the economical clinical trials of specific plant material to treat the viral diseases in the future., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The fast-growing resistance development to several synthetic and microbial insecticides currently marketed highlighted the pressing need to develop novel and eco-friendly pesticides. Among the latter, botanical ones are attracting high research interest due to their multiple mechanisms of action and reduced toxicity on non-target vertebrates. Helicoverpa armigera (Lepidoptera: Noctuidae) is a key polyphagous insect pest showing insecticide resistance to several synthetic molecules used for its control. Therefore, here we focused on the rhizome essential oil extracted from an overlooked Asian plant species, Cheilocostus speciosus (J. Konig) C. Specht (Costaceae), as a source of compounds showing ingestion toxicity against H. armigera third instar larvae, as well as ovicidal toxicity. In acute larvicidal assays conducted after 24h, the C. speciosus essential oil achieved a LC 50 value of 207.45µg/ml. GC and GC-MS analyses highlighted the presence of zerumbone (38.6%), α-humulene (14.5%) and camphene (9.3%) as the major compounds of the oil. Ingestion toxicity tests carried out testing these pure molecules showed LC 50 values of 10.64, 17.16 and 20.86µg/ml, for camphene, zerumbone and α-humulene, respectively. Moreover, EC 50 values calculated on H. armigera eggs were 35.39, 59.51 and 77.10µg/ml for camphene, zerumbone and α-humulene, respectively. Overall, this study represents the first report on the toxicity of C. speciosus essential oil against insect pests of agricultural and medical veterinary importance, highlighting that camphene, zerumbone and α-humulene have a promising potential as eco-friendly botanical insecticides., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Monodon baculovirls (MBV), external fouling organisms (EFO) and bacteria (especially Vibrio species) were monitored during 1996-1997 at nine different Penaeus monodon rearing hatcheries in India. Total cultivable heterotrophic bacteria, Vibrio-like-bacteria, presumptive Vibrio harveyi, Vibrio anguillarum, Vibrio vulnificus counts were determined from shrimp eggs, post larvae, rearing tank water, source sea water, feed (Artemia nauplii and microencapsulated feed). The MBV infected post larvae and their environment showed higher Vibrio-like-bacteria than uninfected post larvae. An overwhelming predominance of presumptive Vibrio harveyi and Vibrio anguillarum was observed in post larval rearing tank water, MBV infected and uninfected post larvae. Vibrio-like-bacteria in Artemia nauplii clearly showed the possible source of these pathogenic bacteria in the hatchery environments. Quantitative analysis of Vibrio-like-bacteria in hatcheries revealed that when the Vibrio-like-bacteria increases to 2 x 10(2) CFU mortality of the post larvae occurs. Abundance of these micro-organisms in hatchery samples indicated that they are opportunistic pathogens which can invade the shrimp tissue, subsequently cause disease when the post larvae were under stressful conditions.