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Authors: A.A. Prathiba, F. Sumaiya Idroos and Pathmalal M. Manage

Journal: Environment and Natural Resources Journal

The present study records the detection of PAHs such as naphthalene and anthracene and isolation of PAHs degrading bacteria from a restaurant site, Weras River Park, in Boralesgamuwa, Sri Lanka. Water samples were collected in seven locations of the study area. Water temperature (oC), pH, and electric conductivity (EC) were measured at the site itself using standard meters. Nitrogen nitrate (N-NO3-) and total phosphate (TP) were measured at the laboratory following the standard methods. Following the extraction of PAHs in collected water samples, detection was carried out using the PDA-HPLC diode array method. PAH degrading bacteria were identified using microplate assay. The selected bacteria strains were subjected to degradation kinetic studies following molecular identification by 16S rRNA analysis. Phylogenetic analysis identified Achromobacter spanius as potential naphthalene degrading bacteria, where Alcaligens faecalis was recorded as an anthracene degrader. Degradation study confirmed that A. spanius efficiently degraded naphthalene at the rate of 0.145±0.002 ppm/day, whereas A. faecalis degraded anthracene at the rate of 0.181±0.036 ppm/day, respectively. Degradation of structures of the Naphthalene and Anthracene by A. spanius and A. faecalis was further analyzed by Fourier Transform Infrared Spectroscopy (FTIR). This is the first record on naphthalene degradation by the bacterium A. spanius.

Authors: J.M.N.J.Jayathilake, K.V.K Gunathilake

Journal: The European Zoological Journal

Marine toxins have received global attention for their involvement in human intoxication. Many marine phyla are well adapted to produce venoms or toxins protect themselves from associated micro fauna, predators and pathogens. Despite the toxicity, some bio toxins stand as potential drug leads in human and veterinary medicine. Amongst all marine fauna, Cnidarians are well renowned for producing bioactive peptides which are used in drug development, as they harbor various biological activities; anticancer, anti-inflammatory, immunomodulatory, radical scavenging, anti-parasitic activities, etc. Particularly, this review summarizes the bioactivities recorded from Cnidarian toxins and the possibility of using them as therapeutic agents, leading to develop into commercial products in the future.

Authors: H. S. D. Fernando, Menaka Hapugoda, Rushika Perera, William C. Black, B. G. D. N. K. De Silva

Journal: PLoS ONE

Phylogeographic relationships among global collections of the mosquito Aedes aegypti were evaluated using the mitochondrial Cytochrome C Oxidase 1 (CO1) and NADH dehydrogenase subunit 4 (ND4) genes including new sequences from Sri Lanka. Phylogeographic analysis estimated that Ae. aegypti arose as a species ~614 thousand years ago (kya) in the late Pleistocene. At 545 kya an “early” East African clade arose that continued to differentiate in East Africa, and eventually gave rise to three lineages one of which is distributed
throughout all tropical and subtropical regions, a second that contains Southeast Asian/Sri Lankan mosquitoes and a third that contains mostly New World mosquitoes. West African collections were not represented in this early clade. The late clade continued to differentiate
throughout Africa and gave rise to a lineage that spread globally. The most recent branches of the late clade are represented by South-East Asia and India/Pakistan collections. Analysis of migration rates suggests abundant gene flow between India/Pakistan and the rest of the world with the exception of Africa.