University of Sri Jayewardenepura: Journals & Proceedings
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Diversity and Conservation of Medicinal Plants around Madduvil Sivan Kovil Area, Northern Province, Sri Lanka
No full textMedicinal plants, growing naturally in diverse habitats, have been utilized in Siddha, Ayurvedic, and traditional medicine for over 5,000 years. This study focuses on the diversity and conservation of medicinal plants around the Madduvil Sivan Temple, located in the Meesalai Grama Sevaka Division J/312 Madduvil Maththi, Chavakacheri. Conducted from January 2024 to March 2024, the research identified a maximum of 113 medicinal plant species across 23 families, including notable families such as Acanthaceae, Asteraceae, Cucurbita, Verbenaceae, Fabaceae, and Malvaceae and authenticated by the Department of Gunapadhan, Faculty of Siddha Medicine, University of Jaffna. Among these, several endemic species were documented, highlighting the unique and vulnerable biodiversity of the area. Based on morphological characteristics, the plants were classified as herbs (31.8%), shrubs (10.6%), creepers (9.7%), climbers (17.4%), and trees (30%). The parts used for medicinal purposes included roots (30 species), leaves (78), seeds (15), fruits (22), stems (5), bark (21), wood (5), latex (6), tubers (4), and whole plants (20). Further classification based on plant form included herbs (36), shrubs (12), creepers (11), climbers (20), and trees (34). The species were categorized into expectorant (7 species), diuretic action (6), diaphoretic (7), antiseptic (5), alternative action (3), and rejuvenation action (12) according to pharmacological action based on the traditional and literature validation, This study documented many medicinal plants, which is helpful for further research that leads to the discovery of new medicine and the preparation of siddha, ayurvedic medicine. Conservation of these medicinal plants is vital for future research, contributing to discovering new medicines and preparing Siddha and Ayurvedic formulations. The Northern Province Indigenous Department has initiated various conservation measures, including the establishment of herbal gardens in each district, promoting herbal gardens in schools, and encouraging home gardening. These efforts aim to preserve rich medicinal plant biodiversity for future generations.
Keywords: Medicinal plants, Siddha medicine, Diversity conservation, Diversit
Evaluation of the Photocatalytic Activity of Chitosan-G-C3N4 Composite for Methylene Blue Degradation
No full textThe growing concern over environmental pollution has driven research into effective, sustainable solutions, particularly in the field of water treatment. This study investigated the photocatalytic activity of a chitosan- g-C3N4 composite, aimed at degrading methylene blue (MB), a prevalent organic dye and pollutant in wastewater. Chitosan (CS) was synthesized from shrimp shells using a series of chemical processes, including demineralization, deproteination, and deacetylation, while graphitic carbon nitride (g-C3N4) was synthesized via thermal treatment of urea. The composite was prepared by mixing varying ratios of CS and g-C3N4, and its photocatalytic efficiency was tested against MB solutions of different concentrations under visible daylight including MB solution, chitosan and MB solution, g-C3N4 and MB solution as controls. Results showed that the chitosan-g-C3N4 composite effectively degraded methylene blue, and the degradation efficiency depends on the composite ratio and MB concentration. The highest rate constant of 10.6 × 10⁻³ min⁻¹ was obtained with 2 ppm MB solution using 1:1 ratio of CS to g-C3N4, while a 1:2 ratio demonstrated optimal degradation rates for both 4 ppm and 5 ppm MB solutions, achieving a rate constant of 6.5×10⁻³ min⁻¹. The 1:2 ratio of chitosan to g-C3N4 consistently provided one of the most efficient degradation rates across concentrations, especially at 2 ppm. These findings underscore the potential of g-C3N4 and its composites with chitosan, particularly those with higher g-C3N4 content, to significantly improve photocatalytic degradation of MB compared to chitosan alone. The optimum performance was achieved at lower MB concentrations (2 ppm), with the 1:1 and 1:2 ratios being particularly effective. The enhanced photocatalytic activity is attributed to the synergistic interaction between chitosan and g-C3N4, where chitosan’s adsorption properties complement the photocatalytic abilities of g-C3N4 by facilitating the separation of photogenerated electron-hole pairs and reducing recombination. This study highlighted the potential of using chitosan- g-C3N4 composites for wastewater treatment applications. By utilizing waste-derived chitosan, this approach not only enhances photocatalytic processes but also contributes to sustainable material development. The findings suggest that the composite can serve as an eco-friendly, cost effective, and efficient photocatalyst for degrading organic pollutants in wastewater, making it a promising and scalable solution for addressing water contamination challenges.
Keywords: Photocatalysis, Chitosan, g-C3N4, Methylene blue, Wastewater treatmen
Identifying Forest Fires and their Impact on Forest Cover in Anuradhapura District Using GIS and Remote Sensing
Get PDFLablab purpureus (L.) is an important leguminous crop that ensures food security. Despite being considered an underutilized crop in Sri Lanka, it is a promising climate-resilient crop with higher protein amounts. However, none of the studies on the diseases in this crop have been performed within the country. Our objective was to identify the diseases and management packages. The disease identification was conducted using the germplasm collection of L. purpureus established at the Horticultural Crops Research and Development Institute. Morphological character analyses of diseased plant samples were followed by culturing parts on a PDA medium to isolate pathogens. The pathogenicity of isolated pathogens was confirmed through standard procedures in Koch's postulate. Pathogen isolates were identified morphologically, and species-level identification was done by extracting genomic DNA and amplifying and sequencing ITS-1 and ITS-4 regions. NCBI BLAST analysis corroborated the results obtained from morphological observations and colony characteristics. This study's findings hold promise for identifying and managing diseases affecting L. purpureus in future cultivation. Under pathogenicity testing, there were 6% foot and root rot disease incidences, and 4% Charcoal rot (ash stem blight) disease incidences were recorded. The distinguishing symptoms of foot and root rot were yellowing, wilting, and basal rot with the presence of Sclerotia in the plant base and symptoms of charcoal rot were yellowing and browning of leaves, stem discoloration with characteristic black patches in root and stem. The causal organisms of foot and root rot were identified as Athelia rolfsii (Sclerotium rolfsii), and charcoal rot was identified as Macrophomina phasealina. With the use of literature and the use of poison food techniques, we developed two disease management packages for both diseases. For foot and root rot control; remove infected plants with soil, Crop rotation, or following, Spot application of recommended fungicides (Captan 50% WP, Thiram 80% WP, Thiophanate-methyl 50% + Thiram 30% WP), Improve the drainage at field preparation, Deep plowing and expose soil to the direct sunlight, Minimize the root damage, and Seed treatment (Captan 50% WP3g/1kg, Thiram 80% WP2g/1kg, thiophanate- methyl 50% + Thiram 30% WP2g/1kg). And also, for ash stem blight control; Following the field or crop rotation (recommended for at least 2yrs), Proper spacing with recommended plant density, Proper nutrient management, Improving the plant vigor, Flood the field 3-4 weeks before planting to destroy the pathogen, and cannot take efficient control by chemical control only.
Keywords: Athelia rolfsii, Charcoal rot, Foot and root rot, Lablab bean, Macrophomina phaseolin 
An Analysis of Water Quality in Surface Water of Kalu River Basin, Sri Lanka in the First Inter-Monsoon Season 2024
No full textThe Kalu River is the major urban water source for the Rathnapura and Kaluthara districts. It originates from the Sri Pada Mountain of the wet zone, and it collects rainfall from the western slopes and falls into the sea at Kaluthara after traversing about 129 km with a catchment area of approximately 2766 km2. The river experiences frequent floods and large-scale inundation during wet season, particularly in cultivated areas and industrial zones. Therefore, it brings a high amount of agrochemicals, pollutants through several industries, along with pollution from the annual Sri Pada pilgrimage. This study was conducted to analyze water quality in Kalu River for physical, chemical and biological parameters during the first inter-monsoon season, coinciding with Sri Pada pilgrimage in 2024. Water samples were collected from 30 selected points along the river basin, focusing on potential pollutant zones. Parameters tested included temperature, turbidity, salinity, TDS, color, Electrical Conductivity, pH, chloride, alkalinity, total hardness, total phosphate, sulphate, nitrite, nitrate, fluoride, total iron, free ammonia, total coliforms, and Escherichia coli. The average river temperature was recorded at 29 0C and pH values fell within the standard range. Salinity, TDS, and electrical conductivity values were acceptable in 99% of samples, while color ranged from 22 to 960 Hazen units. The total hardness, chloride, and alkalinity values were within acceptable limits for drinking water. Sulphate, nitrite, nitrate and fluoride concentrations were found to be very low. All these parameters were within the safe ranges according to SRI LANKA STANDARD 614: 2013 and ISO 9308-1 2014 specifications for potable water quality. However, turbidity, color, total Phosphate, total Iron, and free ammonia posed a risk limit for % of the samples. Among the sampling locations, 100% of samples were contaminated with total coliform and Escherichia coli, exceeding standard levels. This highlights the need for targeted conservation and management strategies in drinking water quality treatments.
Keywords: Water quality, Kalu River, Surface wate
Heavy Metal Contamination in Negombo Estuary: A Study on Water and Sediment
No full textAs a result of industrialization and urbanization, the Negombo estuary has become polluted with domestic waste and various hazardous chemicals including heavy metals, causing serious health concerns. The water enters the Negombo lagoon from the southern part through the Dutch Canal, Ja Ela, and Aththanagalu Oya rivers. The present study was performed to assess the levels of eight heavy metals, Cr, Mn, Fe, Cu, Zn, Cd, Pb & As in estuarine water and sediment samples collected from 11 and 4 sampling sites respectively, using Inductively Coupled Plasma-mass Spectrometry (ICP-MS). All the estuarine water and sediment samples were collected in the dry season of 2021 (December). Heavy metal levels in sediment samples were greater than in the respective water samples. The highest and the lowest levels of Mn in water were reported in sites 7 and 11 respectively (p=0.052), indicating marginal significance. The comparison between the highest and the lowest concentrations of all other tested metals in water was not statistically significant (p>0.05). Moreover, the highest levels of Cr, Cu and Pb were found in the water samples collected from the Northern side while Mn, Zn and Fe were found in elevated levels in water samples collected from the Southern region. The distribution of Cd and As in estuarine water did not show any particular trend. In sediment samples, except As, all other seven heavy metals analyzed were higher in the Eastern region (site 6) of the estuary than in the Northern region (sites 2,3 and 5). The highest and the lowest levels of Zn in estuarine sediment were reported in sites 6 and 2 respectively (p<0.05), indicating statistical significance. The variation in the distribution of heavy metals in the Negombo estuary indicates the influence of domestic and municipal solid waste and the discharge of industrial effluents to the estuarine environment. Additionally, sediment characteristics like fine particle size contributed to enhanced heavy metal accumulation in specific regions. Despite compliance with Sri Lankan water quality standards, it is important to prevent the excessive entry of heavy metals into the lagoonal environment. Therefore, implementing proper treatment facilities for industrial waste is necessarily important.
Keywords: Heavy metals, Negombo estuary, Inductively coupled plasma-mass Spectrometr
Preliminary Physiochemical Analysis of Herbal Solid Waste Generated from Selected Ayurvedic Kwatha Manufacturing Process
No full textHerbal solid waste generated from Ayurvedic industry is abundant and sharp. Dumping them in landfill sites or open spaces near industrial sites raises various environmental concerns. This study is aimed at investigating the potential of herbal solid waste generated from the Ayurvedic industry to be utilized in waste valorization in order to promote sustainability and innovation in resource management. Therefore, the chemical and physical properties of herbal solid waste (residues) discarded from four selected Ayurvedic Kwatha (decoctions) manufacturing processes were analyzed. Residues from Thripala Kwatha, Medhaharani Kwatha, Daruparpata Kwatha, and Patolakatukabiru Kwatha have been selected since these are frequently used in primary healthcare. The moisture contents of the residues ranged from 8±1% to 13±1%. The ash contents of the residues ranged from 3.0±0.2% to 6.2±0.3%. In this study, the highest antioxidant activity was obtained in Thripala Kwatha (IC50 101.76±0.02 g/mL) residue in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The methanolic extract of Thripala Kwatha residue exhibited the highest total phenolic content (13.81±0.07 mg GAE/g) of all the methanolic extracts of the residues evaluated. The mineral content of the Kwatha residues were also evaluated using flame atomic absorption spectroscopy. The Ca content of the residues ranged between 0.74% to 3.60%. The Mg content of the residues ranged between 0.12% to 0.35%. The highest Pb (3.8 g/g), Zn (58.4 g/g), and Mn (153.4 g/g) content was obtained in the Medhaharani Kwatha residue. The highest Fe (909.8 g/g), and Cu (8.3 g/g) content was obtained in Daruparpata Kwatha residue. The highest condensed tannin content was detected in Thripala Kwatha (0.064±0.004 mg CE/g) residue in vanillin-HCl assay. In the disc diffusion assay, the methanolic extract of Thripala Kwatha residue inhibited the growth of Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa at 0.04 mg/mL concentration indicating the highest antibacterial property among all the Kwatha residues analyzed. This study suggests that this herbal solid waste has the potential for further research and development, as well as a number of industrial applications, including those in the pharmaceutical, cosmeceutical, nutraceutical, and agricultural industries, since these residues contain significant bioactive components.
Keywords: Kwatha residues, Waste valorization, Antioxidant activity, Antibacterial activity, Mineral conten
Isolation, Characterization and Identification of Thermo-Stable Amylase Enzyme Producing Bacteria from Compost Production Sites
No full textThermophilic bacteria have altered to thrive and function in relatively hot environments. They can produce thermo-stable enzymes that can survive under high temperatures. Among other enzymes, amylase plays an important role in food, paper and textile industries. Amylase enzyme production has reached up to 30% of the global enzyme market. Therefore, this study has focused on thermo-stable amylase enzymes producing bacteria. The samples were collected from compost production sites at Govijanaseva Department, Kadawatha (sample 01) and Seethawakapura compost site, Awissawella, (sample 02). The standard pour plate method and streak plate method were carried out using Nutrient Agar plates at room temperature to observe bacterial colonies. Bacterial isolates were screened for the production of amylase enzymes using a starch hydrolysis test. The secondary screening for the enzyme activity was conducted using Di-nitro salicylic acid (DNS) assay and the effect of temperatures and pH levels on crude enzymes of amylase producing bacterial isolates were determined. The genomic DNA of the most promising bacteria was extracted and the 16S rRNA gene sequencing was performed for molecular identification. The soil samples were collected at 61 (sample 01) and 65 (sample 02) of temperature. Ten and seven morphologically different bacterial colonies were observed from sample 01 and sample 02 respectively. Out of ten morphologically different bacterial colonies, 04 isolates (GV5, GV6, GV9 and GV10) and out of seven bacterial colonies 04 colonies (SW1, SW2, SW3 and SW4) were positive for the production of thermo-stable amylase enzyme. GV2 was shown to have the highest optimum temperature of 70 and optimum pH 8 for amylase enzyme activity from the sample 01. The optimum temperature and pH for amylase activity was recorded as 80 and pH 6 respectively from the sample 02 (SW2). The molecular identification was carried out only for the sample 02 and SW2 was identified as Bacillus subtilis. As per the results, the bacterial isolate: GV9, SW2 were identified as the most potential bacteria for biotechnological processes and industrial uses under high temperatures.
Keywords: Biotechnology, Compost, Thermo-stable amylase, Thermophilic bacteria
 
Assessment of Short-Term Dynamics in Tree Diversity in Wet Zone Rainforest, Sri Lanka
Get PDFForest cover in Sri Lanka has changed rapidly during the last century. Tree diversity assessment is a crucial requirement at present due to pressure on forests from human activities. This study addresses changes in tree diversity and endemism in wet zone rainforests in Sri Lanka from 2017 to 2022. This study employed a multi-step approach to assess diversity using forest inventory data obtained from the Forest Department of Sri Lanka for the year 2017 and 2022 at same locations. Further, the sample locations were selected randomly throughout the wet zone forest, covering all the conserved, reserved and to be forests. Initially, the Shannon-Weiner index was used to assess diversity, followed by applied Pielou’s index and Margalef index to determine evenness and species richness, respectively. Subsequently, Non-metric Multi-Dimensional Scaling (NMDS) analysis was used to analyze species occurrence variation from 2017 to 2022. Finally, an analysis of similarities (ANOSIM) was employed to further investigate species variation over the same period. The findings revealed an increase in both diversity and species richness, as indicated by the Shannon-Weiner index and Margalef index, respectively. However, species evenness showed a decline according to Pielou’s index. On average, the Shannon-Weiner index (H′) varied from 2.27 to 2.33 while the evenness index changed from 0.86 to 0.85, and the species richness Margalef index shifted from 15.39 to 16.17 from 2017 to 2022, respectively. The study also observed that the numbers of species, genera, and families tended to decrease with rising altitudes in wet zone forests. The finding that invasive plant species considerably increased by 28.71% while endemic plant species decreased by 18.74% was particularly concerning. Among these, Alstonia macrophylla was the most widespread invasive species across the wet zone, while Acacia mangium and Annona glabra were newly recorded invasive plants as of 2022. These findings offer essential insights for land managers, policymakers, and conservationists, highlighting the urgency of promoting conservation measures to protect endemic and threatened species to maintain ecosystem resilience and long-term stability. This study's results will signify the proper control of invasive species within the wet zone forests and management practices aimed at protecting Sri Lanka's rich biodiversity and mitigating further ecosystem degradation.
Keywords: Vegetation dynamics, Short term diversity, ANOSIM, Evenness, NMDS, Species richness, Tree diversit
Trade offs Between Sustainable Forest Management in Conservation Areas and Carbon Balance in Wood Products
Get PDFSustainable forest management is a strategy for dynamically adapting to changing conditions, such as climate change. This comprehensive strategy seeks to balance social, environmental, and economic interests, which can sometimes be conflicting. Emphasizing management activities that target specific ecosystem services can directly influence forests' capacity to perform their functions effectively and equitably. Wood production is considered as the main benefit of the forests and is directed towards the production of harvested wood products. The carbon storage in wood products and their substitution for fossil-based materials and fuels enhances the overall forest sector's contribution to the carbon balance. The ongoing transformation of conservation areas in Slovakia, defined by the Envirostrategy 2030, has introduced changes in forest management of protected areas by establishing territories without human intervention. These areas should reach 50% by 2025 of the total area of each national park. The aforementioned change in the care for forest ecosystems will affect, among other things, the production of wood. The objective of the study is to analyze trade offs between forest management changes in conservation areas and the volume of carbon stored in wood products due to the availability of wood raw materials. Projected volume data for three scenarios considering 20% (baseline), 50% and 75% non-intervention management regimes are redistributed into the roundwood quality categories and used for estimates of wood product outputs. Finally, Standard IPPC procedures are applied to calculate volume and changes in carbon stored in wood products by 2040 under each scenario. The key findings of the study confirmed that in the most extreme scenario, the volume of harvested timber from these areas is expected to decrease by over 70% till 2050. As a result, the forest-based sector will face shrinking timber supplies with the softwood sawmilling sector as the most affected and carbon pool in wood products will tend to decrease and the future carbon emissions will overcome captures. As a part of ongoing research, the overall assessment is considering the whole forestry and forest-based industry contributions to carbon balance as well as other social, economic and environmental aspects.
Keywords: Sustainable forest management, Conservation areas, Carbon balance, Wood product
Fruit Peel Wastes as Novel Media for Growing Selected Fungi
No full textMost of the fruit peels are either dumped or incinerated to a large extent after the main parts of the fruits are consumed. This will cause environmental pollution, and the dumped fruit peel waste will encourage the growth of soil-borne pathogens. The fruit peels are more useful for either agricultural purposes or for other research activities. Fruit peel wastes rich in carbohydrate content and other basic nutrients could support growth of microbes. Potato Dextrose Agar (PDA) is a common medium to grow a wide range of fungi. But nowadays the use of readymade culture media for routine laboratory work and research purposes is quite expensive. Thus, it is essential to formulate cheap culture media. The aim of the present study was to formulate culture media using fruit peel waste material such as pineapple, banana, papaya and watermelon separately. Potato dextrose broth was used as control. The fruit peels of pineapple, banana, papaya and watermelon were dried and powdered. 4g of each fruit peel waste powder was dissolved in 100 mL distilled water separately and autoclaved at 121°C for 15 mins. The pure cultures of fungi namely Rhizopus sp, Aspergillus sp, Penicillium sp, Mucor sp and Fusarium sp were obtained in the laboratory. Qualitative measurements were taken. Most of the media showed higher growth of fungi compared to the Potato dextrose broth. Growth of Rhizopus sp, Aspergillus sp, Penicillium sp and Mucor sp was recorded in all the fruit peel waste media. Among all the fruit peel waste media tested, growth of Fusarium sp was not observed in media containing pineapple and banana. The nutritional composition of the fruit peel and the presence of certain bioactive compounds may have influenced the variation of the growth of fungi in different fruit peel media. Future studies should be done to formulate suitable media from fruit peel wastes which encourages the growth of certain fungi.
Keywords: Fruit peel waste, Potato dextrose broth, Fung