title: Synthesis and larvicidal activity of low-temperature stable silver nanoparticles from psychrotolerant Pseudomonas mandelii.
abstract: Applications based on silver nanoparticles (AgNPs) are limited by low temperatures, which cause aggregation of the nanoparticle fraction, leading to reduced efficacy of their products. We aimed at studying AgNP synthesis by psychrotolerant bacteria, its stability under long-term storage, and larvicidal activity under low-temperature conditions. Electron and atomic force microscopy studies revealed that 6 among 22 psychrotolerant isolates synthesized AgNPs with an average diameter of 1.9-14.1 nm. Pseudomonas mandelii SR1 synthesized the least-sized AgNPs with an average diameter of 1.9-10 nm, at temperatures as low as 12 °C without aggregate formation, and the synthesized nanoparticles were stable for up to 19 months of storage period. On studying their larvicidal activity, LC90 (lethal concentration) values against Anopheles subpictus and Culex tritaeniorhynchus larvae were at 31.7 and 35.6 mg/L, respectively. Stable non-aggregate AgNPs at low-temperature conditions from P. mandelii SR1, coupled with their larvicidal property, can be applied to control larval populations in water bodies located in seasonal or permanently cold environments.
authors.affiliation: School of Bio Sciences and Technology, VIT University, Vellore, Tamil Nadu, 632014, India.
authors.forename: Anbazhagan
authors.initials: A
authors.lastname: Mageswari
authors.forename: Parthiban
authors.initials: P
authors.lastname: Subramanian
authors.forename: Vini
authors.initials: V
authors.lastname: Ravindran
authors.forename: Sreelekha
authors.initials: S
authors.lastname: Yesodharan
authors.forename: Asokan
authors.initials: A
authors.lastname: Bagavan
authors.forename: Abdul Abdul
authors.initials: AA
authors.lastname: Rahuman
authors.forename: Sivashanmugam
authors.initials: S
authors.lastname: Karthikeyan
authors.forename: Kodiveri Muthukaliannan
authors.initials: KM
authors.lastname: Gothandam
mesh_terms: D000818:Animals; D000852:Anopheles / Q000187:drug effects; D003080:Cold Temperature; D003465:Culex / Q000187:drug effects; D004355:Drug Stability; D007306:Insecticides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D053768:Metal Nanoparticles / Q000737:chemistry*; D011549:Pseudomonas / Q000737:chemistry / Q000378:metabolism*; D012834:Silver / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D007306:Insecticides; D012834:Silver