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Item Evaluation of the effect of oxidizing and reducing agents on trypsin inhibitory activity of Vigna mungo seeds (Black Gram)(Faculty of Science, University of Kelaniya, Sri Lanka, 2021) Jayasinghe, J. D. M. S.; Chandrasena, U. S. D.; Kumari, K. D. K. P.; Rajapakse, S.; Suresh, T. S.Trypsin is one of the widely distributed serine proteases in living organisms, which is involved in vital physiological functions. In spite of its involvement in survival of the organisms, it was reported that trypsin is associated in pathogenesis of different type of human cancers. Therefore, trypsin inhibitory proteins have been gained attention as a potential treatment strategy against such cancers. Seeds of legumes have been recognized as potential natural resources of trypsin inhibitory proteins. Black gram (Vigna mungo) is a popular legume cultivated in Sri Lanka and Field Crops Research and Development Institute of Sri Lanka (FCRDI) has released a novel breed of black gram called Anuradha. The attempts were made to assess trypsin inhibitory activity (TIA) of its seeds and characterization of the active trypsin inhibitory proteins for future discovery of anticancer agents. The objectives of the present study was to evaluate the effect of oxidizing and reducing agents on the activity of trypsin inhibitory proteins present in seed of the local variety and to investigate the ionic nature of active proteins using ion exchange chromatography. Fresh mature seeds of variety Anuradha were collected from FCRDI and the crude protein extract (20%) of milled seeds was prepared using distilled water. The TIA of the extract was assessed by the method explained by Kunitz (1947) with slight modifications. To evaluate the effect of oxidizing and reducing agents on TIA, the seed extract was incubated with hydrogen peroxide (1-2%, v/v), dimethyl sulphoxide (1-5%, v/v) and varying concentrations of β-mercaptoethanol for 30 minutes, followed by the measurement of TIA. To discover the ionic nature of the active proteins, the crude protein extract was fractionated by ion exchange chromatography using positively charged Diethylaminoethyl cellulose as the stationary phase. The column was washed with phosphate buffer (pH 7.4) and then eluted with 1 M NaCl. The absorbance of each eluted fraction was measured at 280 nm. The TIA was assessed for the fractions with highest absorbance values. The TIA activity of the crude protein extract was 73.21 ± 0.29%. In the presence of the oxidizing agents, dimethyl sulfoxide and hydrogen peroxide the TIA of the test extract was 59.91 ± 0.69% and 27.08 ± 0.34% respectively. The activity of seed samples incubated with 0.1 M, 0.5 M, 1 M and 2 M of β-mercaptoethanol was 70.72 ± 0.23%, 58.63 ± 0.53%, 46.31 ± 0.72% and 39.47 ± 0.44% respectively. Ion exchange chromatography resulted one fraction with high protein content at pH 7.4 which exhibited 3.12 ± 0.62% of TIA. The TIA of the washing fraction was 35.46 ± 0.08%. The results of the present study revealed that Dimethyl sulfoxide decreased the TIA in a moderate level while hydrogen peroxide caused a drastic decrease. Increasing concentration of the reducing agent β- mercaptoethanol gradually decreased the TIA of the test sample. The observations of column chromatography indicated that the seed sample of black gram contain active trypsin inhibitory proteins which exist in an anionic or neutral form in pH 7.4.Item Host Plant Preference of Genera Dendrobium and Bulbophyllum (Family: Orchidaceae) in Sri Lanka.(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Sandamali, P. M. H.; Senanayake, S. P.; Benjamin, S. P.; Rajapakse, S.; Athukorala, N. P.Orchids are a well-known plant family for their restricted distribution in the wild. Most epiphytic orchids are hosted by specific trees and hence it’s abundance may be influenced by the availability of suitable host trees and epiphytic composition. The distribution of many epiphytic orchids in nature indicates that they display strong species specificity in selecting hosts and noticeably lacking on other trees. Dendrobium and Bulbophyllum are epiphytic genera and mostly have restricted distribution in the natural environments. Furthermore; they display a biased distribution towards host trees. Therefore, the study aims to investigate the host tree preference of the species of Dendrobium and Bulbophyllum with a view to provide important information for the conservation of these species. Wet forests in Matale (Knuckles mountain range), Nuwara Eliya (Hakgala nature reserve, Horton Plains National Park, Pidurutalagala mountain, Kandeela forest reserve), Baddulla (Namunukula mountain), Kegalle (Makandawa forest reserve), Ratnapura (Sinharaja rain forest, Peak wilderness), Kurunegala (Kankaniyammulla forest), Galle (Hiyare rain forest, Kottawa forest, Morningside forest) districts were explored for the distribution of two genera; Dendrobium and Bulbophyllum. Specimens were collected randomly from the selected sites; three plots of 500m× 500m size per each site, and relevant data of host plants were recorded such as tree height, girth at breast height (GBH), tree bark characteristics (bark colour, nature of the moss cover and bark texture) and the abundance of orchid species on the host tree. Further, herbarium specimens of host trees and the orchids were prepared for identification. Presence of orchid species on the identified host trees was counted and, percentage of frequency was calculated. It was revealed that the orchids are mostly associated with hosts with dense moss cover and rough tree barks. Sixty five percent of species of Dendrobium and Bulbophyllum were found on hosts having 51-100 cm GBHs. Further, these orchids have shown preference to plant families; Myrtaceae (26%), Lauraceae (23%) and Phylanthaceae (16%) as their hosts, whereas, with respect to the genus specificity, highest percentage of these orchids have shown preference to genera Syzygium (family Myrtaceae) and Glochidion (family Phylanthaceae) as their hosts. Findings of the present study have revealed that the species diversity and species richness of genera Dendrobium and Bulbophyllum were high in the montane forests located in Nuwara Eliya (Horton Plains Nature Park, Kandeela forest reserve and Pidurutalagala mountain) and Matale (Knuckles mountain range) districts. This might be due to the fact that these forests were characterized by high humidity and high elevation. Chemical composition, distribution of moss cover and fungi associated with tree barks of these preferred host trees, would provide new insight for the conservation of these epiphytic orchid species.Item Phenetic Diversity and Preliminary Phytochemical Screening of Tephrosia Pers. Spp. (Family Fabaceae) in Sri Lanka(Ceylon Journal of Science (Biological Sciences), 2016) Priyadarshan, A.I.S.; Senanayake, S.P.; Jayatilleke, M.P.; Rajapakse, S.Tephrosia is a genus of medicinally important perennial shrubs or herbs distributed in warm temperate and tropical regions, and belongs to Family Fabaceae. The genus is represented in Sri Lanka with 10 species. The objective of the present study was to interpret interspecific relationships of Tephrosia species in Sri Lanka using phenetic and phytochemical variations. Specimens of six different Tephrosia species including T. purpurea, T. villosa, T. noctiflora, T. tinctoria, T. maxima and T. pumila were collected from their natural habitats in different climatic zones in Sri Lanka. Sixteen floral and vegetative characters of Tephrosia spp. were observed and cluster analysis was performed to interpret phenetic relationships. Herbarium specimens were prepared and voucher specimens were submitted to the National Herbarium, Peradeniya. Phenogram indicated the presence of interspecific relationship with respect to the morphological characters. Air dried leaves were subjected to sequential solvent extractions using solvents with different polarities such as hexane, chloroform and methanol. These extracts were subjected to preliminary phytochemical screening tests to detect the occurrence of carbohydrates, protein and amino acids, glycosides, alkaloids, saponins, flavonoids, tannins, phenolics, and phytosteroids. Phytochemical screening of the different Tephrosia spp. indicated a close relationship among the species and further isolations and purifications are needed to elucidate the chemical constituents to assess the efficacy.Item Development of Suitable Propagation Systems for Tephrosia spp. in Sri Lanka(University of Kelaniya, 2014) Priyadarshan, A.I.S.; Senanayake, S.P.; Jayatilleke, M.P.; Rajapakse, S.Genus Tephrosia (Fabaceae) commonly known as ‘Pila’ in Sri Lanka. Some Tephrosia spp. are used in many traditional therapeutic preparations in Sri Lanka and also in other countries. Increased use of Tephrosia in traditional therapeutic systems has developed a great demand for these species. Thus production of planting materials for commercial cultivation has become a timely requirement. Therefore, this research was conducted to determine suitable propagation systems for four selected Tephrosia spp.; T. purpurea, T. villosa, T. noctiflora and T. pumila. Even though seeds of Tephrosia spp. showed high viability, lower germination percentage was observed on wet filter paper as well as in six different potting media [M0 (Coir: dust: Sand; 1:1:1), M1 (Coir dust: Sand: Top soil; 1:1:1), M2 (Coir dust: Sand: Top soil: Compost; 1:1:1:1), M3 (Coir dust: Sand: Top soil: Compost: Cow dung; 1:1:1:1:1), M4 (Coir dust: Sand: Compost; 1:1:1), M5 (Coir dust: Sand: Top soil: Cow dung; 1:1:1:1)] during a period of one week. Water impermeability of seed coats was identified as the main reason for the seed dormancy in Tephrosia spp. and soaking seeds in Con. H2SO4: H2O; 3:1 for 25 minutes and rubbing seeds on sandpaper for 2 minutes were determined as suitable dormancy breaking methods. Variation was observed in the growth performance of Tephrosia spp. in six different potting media. Growth performances of seedlings of Tephrosia spp. in hydroponic solution and soil medium were observed and soil medium was selected as the most suitable medium for the growth of Tephrosia species based on their growth performances.Item Intraspecific Variation of Flueggea leucopyrus Willd. Grown in Sri Lanka and Establishing a Suitable Propagation System(University of Kelaniya, 2014) Priyadarshan, A.I.S.; Senanayake, S.P.; Jayatilleke, M.P.; Rajapakse, S.Flueggea leucopyrus belongs to family Phyllanthaceae, commonly known as ‘Katupila’or ‘Heen katupila’ and has become increasingly popular as an ingredient in several traditional therapeutic systems in Sri Lanka as well as in other Asian countries. A questionnaire survey was carried out using a hundred population sample to determine the awareness of the distribution and therapeutic uses of F. leucopyrus in Sri Lanka as a preliminary survey. The aims of the present study were to interpret the phenetic variation and determine the variation of phenolic composition in leaf extracts of F. leucopyrus in different climatic zones in Sri Lanka and to develop a suitable propagation system for F. leucopyrus. Eleven floral and vegetative characters of F. leucopyrus were observed and cluster analysis was carried out to infer phenetic relationships among populations collected from localities, Colombo, Kurunegala, Puttalam and Hambanthota, .representing different climatic zones. Medicinal value of most of plants lies in phytochemicals such as phenolics, flavonoids and anthocyanidins. Thus, leaf samples were extracted into ether, and ether extracts were used to isolate phenolic compounds using 2-Dimensional paper chromatography in solvent systems, butanol: acetic acid: water; 6:7:3 and sodium formate: formic acid: water; 10:1:200. Colors of the spots were observed under UV (366nm), and Rf values were calculated. Intra specific variations were observed in the distribution of phenolics in leaves and phenetic characters of F. leucopyrus with respect to their habitats in different climatic zones. Due to low seed production in F. leucopyrus, stem cuttings (Semi-hardwood, hardwood and softwood) in three different potting media were used to evaluate the successfulness in propagation. Semi hardwood and hardwood cuttings of F. leucopyrus were well established within a period of one week in sand potting medium while softwood cutting has not responded in any of the media during the period. Medium with only coir dust was also not successful in establishing the cuttings.