Kasun Aththanayake

University of Kelaniya, Microbiology, Research Assistant

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MPhil in Microbiology (Reading) at University of Kelaniya, Sri Lanka
BSc Graduate at University of Kelaniya , Sri Lanka

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Papers by Kasun Aththanayake

Staphylococcus edaphicus KCB02A11 incorporated with natural adsorbents: first report on its tolerance and removal of hexavalent chromium [Cr(VI)]

World Journal of Microbiology and Biotechnology

Potential use of Chlorella vulgaris KCBAL01 from a freshwater stream receiving treated textile effluent in hexavalent chromium [Cr(VI)] removal in extremely acidic conditions

Journal of Environmental Science and Health, Part A

Development of biofilm/mat for Chromium detoxification

Biofilm formation by Staphylococcus spp. in different media and influence of hexavalent chromium

Comparison of Cr (VI) tolerance of two bacterial species isolated from a waterbody receiving textile effluent

Hexavalent chromium (Cr (VI)) is widely use in textile industry for dying purposes which can be h... more Hexavalent chromium (Cr (VI)) is widely use in textile industry for dying purposes which can be highly carcinogenic due to the high solubility. The Chromium contaminations in water bodies can be removed using chemical, physical and biological methods. The biological methods are comparatively cost effective and environment friendly than other two methods. Hence study of Cr(IV)-microbial interactions are important not only in remediation point of view but also in risk assessment. Bacteria were isolated from a water body receiving textile effluent using standard microbiological techniques. Their preliminary characteristics were studied based on cultural, morphological and basic biochemical features. Bacterial isolates were exposed to different concentrations of Cr(VI) in tris minimal medium (modified) and growth patterns were monitored spectrophotometrically at 600 nm in 24 h intervals and effective concentrations (EC50) were calculated. Isolate A11 was a non endospore forming, non motile Gram positive cocci, which was a catalase and oxidase positive organism. It produced acid and gas in glucose fermentation and was a fermentative organism. Its colonies were circular flat entire colonies having a creamy colour. C9 was a non endospore forming non motile Gram positive cocci showing only the catalase activity and producing acid and gas from glucose fermentation. This was an oxidative organism. The two isolate were identified up to the genus level as Micrococcus sp. and Staphylococcus sp. respectively. During the initial 24 hours from the inoculation organisms into the growth medium, the tolerance of both Micrococcus sp. and Staphylococcus sp. was decreased and a gradual increase of the tolerance was observed along with time period up to 96 hours. EC50 values at 24 h, 48 h, 72 h and 96 h of Micrococcus sp. were 0.207, 0.199, 0.322 and 0.413 respectively. Staphylococcus sp. showed an EC50 of 0.016, 0.016, 0.032 and 0.016 at 24 h, 48 h, 72 h and 96 h respectively. Results indicated that Micrococcus sp. are more resistant to Cr(IV) than Staphylococcus sp.

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