https://ir.kdu.ac.lk/handle/345/3860 Mon, 06 Apr 2026 10:40:44 GMT 2026-04-06T10:40:44Z https://ir.kdu.ac.lk/handle/345/2734 In silico Study of the Binding Affinities of Acetylcholinesterase and Synthetically Viable Coumarin Analogs Afnan, M; Rathnaweera, CN; Udawatte, CS Acetylcholinesterase (AChE) is a serine hydrolase that is responsible for the hydrolysis of acetylcholine-a neurotransmitter associated with the transmission of nerve impulses. The reversible inhibition of AChE can be useful in combatting Alzheimer’s disease (AD). A computational study of the inhibition of AChE was conducted by Molecular Docking using a series of synthetically viable coumarin analogs generated by a program called Autogrow 3.0 using the parent structure as 7-hydroxy-5-methyl-4-(phenoxymethyl)-2Hchromen- 2-one. Each of the generated structures were subjected to an energy minimization via Spartan version 14 programme, the level of theory being B3LYP/6-31G**. The drugs rivastigmine and tacrine were used as reference molecules.The docking software used was AutodockVina, with the crystal structure bearing the PDB ID- 1GQR as the receptor. Out of the 20 ligands investigated 6 of the ligands, namely, C18, C3, C1, C17, C8 and C2 were calculated to have binding affinities of -10.0, -9.5, -9.2, -9.2,-9.2 and -9.0 kJ/mol respectively, all of which are higher in value than the values for those of the two standard drugs, rivastigmine and tacrine, which have values of -7.9 and -8.9 kJ/mol respectively. In addition to this, 9 more ligands showed binding affinities that lay between the range of the two commercial drug molecules used as references. These were- C16, C6, C12, C10, C20, C15, C5, C7 and C14, which showed the values -8.8, -8.8, -8.7, -8.5, -8.4, -8.3, -8.3,-8.2 and -8.0 kJ/mol. Given these evidences, these two groups appear to have the most likely chance of being effective drug candidates for treating Alzheimers disease. Mon, 01 Jan 2018 00:00:00 GMT https://ir.kdu.ac.lk/handle/345/2734 2018-01-01T00:00:00Z https://ir.kdu.ac.lk/handle/345/2733 Applicability of Allium cepa Test to Assess the Degree of Phytoremediation of Soil Contaminated with Used Lubricating Oil by Using Crotalaria retusa L. Walakulu Gamage, SS; Masakorala, K; Brown, MT; Widana Gamage, SMK Indiscriminate disposal of used lubricating oil (ULO) into the soil has become one of the major environmental issues in most of the cities throughout the world. Phytoremediation is a novel technique with a potential to be utilized to remediate ULO contaminated soil. The aim of the study was to investigate the applicability of Allium cepa test to assess the degree of phytoremediation of soil contaminated with ULO by using Crotalaria retusa L. A pot experiment was conducted by using ULO contaminated soils with the contamination levels of 10,000 mg/kg (T1), 20,000 mg/kg (T2) and 30,000 mg/ kg (T3) w/w ULO according to the randomized block design (RBD) with four replicates per each contamination level. At the end of 90 days, A. cepa system showed significantly high Mitotic index (MI) for the treatments with plants (34.51, 23.34 and 20.30) compared to that of unplanted control (27.77, 20.81 and 16.42) for T1, T2 and T3 respectively. The percentage biodegradation (43.75, 32.23 and 22.1) in the C. retusa rhizosphere soil was significantly high compared to that of unplanted control (25.15%, 16.4% and 9.15%) for T1, T2 and T3 respectively. The results infer that the phytoremediation and genotoxicity (MI and chromosomal aberrations) reduction in the treatment with C. retusa varied in time-dependent and contamination-level-dependent manner. The correlation analysis revealed highly positive correlations (r=0.882, 0.970 and 0.961) between percentage ULO biodegradation and MI for 30, 60 and 90 days respectively. Therefore, overall results conclude the potential application of A. cepa test to evaluate phytoremediation of soil contaminated with ULO by using C. retusa L. Mon, 01 Jan 2018 00:00:00 GMT https://ir.kdu.ac.lk/handle/345/2733 2018-01-01T00:00:00Z https://ir.kdu.ac.lk/handle/345/2732 Spectrophotometric Determination of Nitrite Content in Four Brands of Chicken Sausages Somarathne, R; Chilki, D; Somapala, EG; De Silva, V; Udawatte, CS Nitrites are used as preservatives in processed meat. Although they are beneficial and safe at permitted levels, they can be carcinogenic when used in excess. Large doses of nitrites can also lead to a condition known as methemoglobinemia. The aim of this study is to determine whether the nitrite content in four locally available brands of chicken sausages are within the permitted levels. The Griess assay was used to determine the nitrite content in four brands of chicken sausages available in the local market. In the Griess assay, nitrites yield a characteristic dark pink colored complex when reacted with N-1-napthylethylenediamine dihydrochloride (NED) under acidic conditions. The optical density was measured at 540 nm using a UV-Visible spectrophotometer, and nitrite concentration was determined from a calibration curve. The obtained results show brands A, B, C, and D contained 31.1 mg/kg, 43.1 mg/kg, 96.1 mg/kg and 1.2 mg/kg of nitrite respectively. According to the Code of Federal Regulations Title 21 as of April 1 2017, the amount of sodium nitrite present should not exceed 200 mg/kg (ppm) in processed meat. According to our results, the nitrite content of all brands of sausages used in this study were within the permitted levels. Mon, 01 Jan 2018 00:00:00 GMT https://ir.kdu.ac.lk/handle/345/2732 2018-01-01T00:00:00Z https://ir.kdu.ac.lk/handle/345/2731 Associated Factors for Efficient Development of School Sports System for National Level Sports in Sri Lanka Biyanwila, BDLPN; Perera, HPN Sports have turn out to be a global social phenomenon. Sports can be used as a platform for attaining many social goals and resolving persisting social issues. The development of Sri Lankan sports depends on many factors and yet the developments are not satisfactory with regard to national level sports. The development of national level sports mainly depends on schools sports. Therefore, through this study it was intended to identify the major factors associated with efficient sports development in schools in Sri Lanka. Furthermore, it was aimed at identifying problems faced in development phase, and at giving suggestions to minimize those problems. The sample of research was 66 physical education teachers (n=66) from randomly selected schools in Kurunegala district. A likert scale structured questionnaire was used to collected data and data analysis was conducted using MiniTAB statistical data analysis software to elaborate the results. Methods used to analyze data were General Linear Model and Multiple Linear Regression. The Cronbach’s alpha obtained with the present sample was 0848. The findings of the research indicated that factors like human resources, physical resources and administration and policies affect more for the efficient development of school sports, and factors such as talent identification, technology and sociocultural determinants are least influencing factors on efficient sports development in schools. According to the research findings it can be concluded that efficient development of sports in Sri Lankan schools can be enhanced by developing the human resources, physical resources and administration policies which also affect national level sports directly. Mon, 01 Jan 2018 00:00:00 GMT https://ir.kdu.ac.lk/handle/345/2731 2018-01-01T00:00:00Z