Science
Permanent URI for this communityhttp://repository.kln.ac.lk/handle/123456789/1
Browse
2 results
Search Results
Item Microcystin -LR contamination status of Nile tilapia (Oreochromis niloticus) and biomarker response(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Abeysiri, H. A. S. N.; Wanigasuriya, K.; Manage, P.M.Microcystin-LR (MC-LR) is a cyanotoxin derived from some cyanobacteria. Nile tilapia (Oreochromis niloticus) is the most popular freshwater fish among people in Sri Lanka. MC-LR accumulation in tilapia from thirteen reservoirs; Nallachchiya Wewa, Galkulama Wewa, Anakattiya Wewa, Padaviya Wewa, Nachchaduwa Wewa and Kalawewa in Anuradhapura District and from four reservoirs; Parakrama Samudraya, Halmilla Wewa, Kaudulla Wewa and Ambagas Wewa in Polonnaruwa District Muwapatigewela Wewa in Ampara District and Ulhitiya Wewa and Rathkinda Wewa in Badulla District was determined to evaluate the risk posed by the MC-LR contamination in fish on human health. Sample collection, transportation and analysis were followed according to the standard protocols and MC-LR was quantified by High Performance Liquid Chromatography. Fish skin, flesh and head were analyzed for MC-LR and Tolerable Daily Intake (TDI) values were calculated according to the WHO guidelines. MC-LR levels of fish in different reservoirs were compared with WHO standard of TDI (0.04 μg/kg/day). MC-LR level of fish skin (717.14 ± 0.82 μg/kg), flesh (105.11±0.08 μg/kg) and head (553.24±0.12 μg/kg) collected from Padaviya Wewa were recorded the highest mean concentrations of MC-LR. The mean concentrations of MC-LR in the skin and head of fish were significantly higher than that of flesh (p<0.05). The Average Daily Intake of MC-LR in the skin and head of all fish exceeded the provisional TDI set by WHO. Thus, the results of the present study revealed that consumption of head and skin of fish has a potential risk on accumulation of MC-LR in human body. Cyanobacterial toxins have been shown to affect aquatic organisms such as fish, resulting in oxidative stress. Among the antioxidant enzymes, glutathione peroxidase (GPx) plays an important role in the detoxification of MCs. Fish tissues such as head, flesh and skin were obtained for “GPx” gene expression analysis and results showed availability of detoxifying enzymes in fish skin and head collected from Parakrama Samudraya, Padaviya Wewa, Nallachchiya Wewa and Galkulama Wewa. MC-LR contamination in Galkulama Wewa showed a negative result. Therefore, previous exposure of fish for MC-LR shows indicator of the expression of gene of any detoxifying enzyme. Therefore, the results support the use of GPx in fish as a biomarker to assess the contamination by MC-LRItem Determination of variation components of harvested rice seeds grown in selected areas of four grama niladari divisions in North Central Province(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Weerakoon, T.; Jayawardane, B. M.During the last two decades, alarmingly high incidences of kidney failure and some associated deaths have become very significant in certain parts of Madawachchiya district and Uva Province and North Central Province. Since rice is the staple food of Sri Lankans, identification of variation components in rice seeds will be beneficial. Hence, this study aimed to find variation components in rice seeds grown in areas severely affected and not affected by Chronic Kidney Disease of unknown etiology (CKDu) in the North Central Province. After having a discussion with the farmers, rice seed samples of Bg 355 was collected from four grama niladari divisions, Karambankulama, Unagaswewa, Angunachchiya and Kirgollewa. Three samples from each division were randomly collected from different paddy fields which were treated with Compo and M-60 weedicides and the collected samples were stored for 6 months. Certain components of rice seeds such as starch, total flavonoids, free amino acids, crude fiber and crude protein content of rice seeds were tested. Free amino acids was analyzed by Moore and Stein method, flavonoids by Aluminum Chloride colorimetric method, crude fiber was analyzed by filtration method, starch by iodine test and crude protein amount was analyzed by Kjeldahal method. Triplicates (n=3) were done for each assay for each division. Since added fertilizer is common for all the samples, components which vary depend only on the geographical location within the province. Statistical analysis was done using Mini tab 18 version. According to statistical analysis, free amino acids and crude fiber content in Bg 355 rice seeds were comparatively higher in Kirigollewa (0.6750 ± 0.0636) and Angunachchiya (0.6600 ± 0.0283) areas severely affected by CKDu compared to Unagaswewa (0.3950 ± 0.0212) and Karambankulama (0.3800 ± 0.0141) areas less affected by CKDu. Total flavonoids were lesser in rice seeds in Kirigollewa (0.055 ± 0.007) and Angunachchiya (0.075 ± 0.007) areas severely affected by CKDu when compared to Unagaswewa (0.155 ± 0.007) and Karambankulama (0.135 ± 0.007) areas less affected by CKDu. Contents of starch and crude protein amount, does not show any significant difference related to CKDu affected and nonaffected areas. Therefore, this analysis suggests that free amino acids, total flavonoids and crude fiber contents in rice seeds vary depending on the geographical location within the North Central Province. Further experiments in different areas and geographical locations are needed to confirm the variation of these components depending on the geographical location.