Blog – Page 22 – Department of Zoology

18Jan

The discussion for future cyanotoxin research on public health

Prof.Sampath Amaratunge, Vice chancellor of University of Sri Jayewardenepura held a special discussion with Cyanotoxin research experts Prof.Linda Lawton and Dr. Christine Edwards and Prof. Pathmalal Manage, director, Centre for water quality and algae research regarding future research initiatives and collaborations with the CyanoSol, Robert Gordon University, UK. This collaboration will lead to high impact research and exchange of postgraduate students between University of Sri Jayewardenepura and the Robert Gordon University, UK.

Furthermore, Prof.Sampath Amaratunge awarded with fellowships Prof.Linda Lawton and Dr. Christine Edwards to continue their service and support to upgrade the research and publication standards of University of Sri Jayewardenepura.

17Jan

Events, news

Three days workshop on Cyanotoxin tool box II

In par with the 2^nd International symposium on Cyanobacteria and Public health, a three days workshop on Cyanotoxin tool box II was conducted by Prof.Linda Lawton and Dr. Christine Edwards from the 16^th to 18^th January at the Centre for water quality and algae research. Postgraduate students and regional chemists from national water supplies and drainage board (NWSDB) were trained at this workshop.

26804943_2061320917228495_5897513522470000667_n 26904048_2061320913895162_2727665536335939456_n

16Jan

news

Department of Zoology successfully held its annual symposium.

The 2^nd International symposium on Cyanobacteria and Public health, organized by the Centre for water quality and algae research was held on the 15^th January 2018, at the Golden rose hotel, Boralesganuwa. Prof. Sampath Amaratunge, Vice chancellor of University of Sri Jayewardenepura graced the occasion as the chief guest while Dr. Jayantha Wattevidanage, director general, National Science foundation was the guest of honor. Renowned cyanotoxin experts, Prof.Linda Lawton and Dr. Christine Edwards from CyanoSol, Robert Gordon University, UK participated in this symposium as foreign delegates.

30Dec

Publications

In vitro screening of, antibacterial antifungal and cytotoxicity activities in crude extract of freshwater cyanobacterium Oscillatoria sp.

Authors: Manoj Wijesekara & Pathmalal Manage
Journal: Journal of Tropical Forestry and Environment

Cyanobacteria, highly diverse group of prokaryotes are recognized as a potent source of biologically active compounds with antiviral, antibacterial, antifungal, and anticancer properties.The aim of the present study was to screen antibacterial, antifungal and cytotoxic activities of intracellular secondary metabolites of freshwater cyanobacterium Oscillataria sp. Cyanobacterium Oscillatoria sp. was isolated from Senanayaka Samudraya reservoir (70 11’ 37.370N 810 31’ 47.130E), Sri Lanka.In vitro antibacterial and antifungal activity of Oscillatoria sp. was screened against Gram-positive Methicillin-resistant Staphylococcus aureus (MRSA) ATCC 25923, Bacillus anthracis and Gram-negative Pseudomonas aeruginosa (ATCC 25853), Salmonella typhi and Escherichia coli (ATCC 25922) and fungi, unicellular Candida albicans (ATCC 60192) and Candida tropicalis using agar disc diffusion method.The Minimum Inhibitory Concentrations (MIC), Minimum Bacteriocidal Concentration (MBC), Minimum Fungicidal Concentrations (MFC) and cytotoxic effects (brine shrimp bioassay) of Oscillatoria crude extract were determined. 10% and 60% of biomass was extracted with hexane and methanol respectively.Gas Chromatography-Mass Spectrometry (GC-MS) was used to identify compounds in the crude extract. The highest antibacterial and antifungal activity of crude extract were detectedin methanol extract against S.aureus (19 ± 2 mm)and C.albicans (10 ± 1 mm) within 24 hours wherein the hexane extract, antibacterial activity was detected only for S. aureus and mean diameter of inhibition zone was 11 ± 1mm within 24 hours.The lowest MIC of methanol extract against S. aureus wasfound as 156.25 μg/ml. The lowest MBC and MFC of methanol extract againstS. aureus and C.albicans were 0.63 mg/ml and 1.25mg/ml respectively. Lethal concentration, 50% of the crude extract against brine shrimp was recorded at 2.50 g/l, 1.25 g/l and 0.625 g/l for 6, 12, 24 hrs intervals respectively. GC-MS analysis revealed that the methanol crude extract of Oscillatoria sp. contains important fatty acid namely hexadecanoic acid methyl ester, methyl tetradecane and 13-tetradecanoic acid and n-hexane extract contains Bis (2-ethylhexyl hydroxypyridine oxide, 1 2-benzenedicarboxylic acid mono (2-ethylhexyl) ester, Phthalic acid 6-ethyl-3-Octyl heptyl ester and Phthalic acid dodecyl nonyl ester which may possess antibacterial and antifungal properties.