http://ir.lib.ruh.ac.lk/handle/iruor/19176 2026-04-26T18:31:28Z http://ir.lib.ruh.ac.lk/handle/iruor/19339 Effect of cutting type, potting media, and irrigation frequency on the success of vegetative propagation of Iriweriya (plectranthus zeylanicus forssk) Nakandalage, N.; Jayawardhana, W.R.S.; Rathnayaka, R.M.A.P. Plectranthus zeylanicus is an indigenous, multi-functional herb used in traditional medicine. Due to over exploitation from the natural habitats, the species is on the verge of extinction. Therefore, commercial cultivation of the species is needed to satisfy the rising demand while protecting its genetic base. The current study was designed with three trials to identify the most suitable cutting type, potting media, and irrigation schedule for P. zeylanicus. Four distinct cutting types (tip cutting, triple nodal cutting, double nodal cutting and single nodal cutting), five different potting mixtures (topsoil: sand: compost-1:1:1, topsoil: sand: compost-1:2:1, topsoil: sand: compost-1:1:2, topsoil: compost -1:1, topsoil: compost-1:2) and four different irrigation schedules (daily watering to field capacity level, daily watering to half of the field capacity level, every other day to the field capacity level, every other day to half of the field capacity level) were used in Completely Randomized Design with ten replicates. Survival percentage (%), number of leaves, the height of the plant (cm), average length of roots (cm), average leaf area (mm2), and chlorophyll content (SPAD Unit) were measured as growth parameters. Data were analyzed using SAS software with a 5% significance levels. Highest survival percentage (95%), highest average root length (26.8 cm), average leaf area (80.5 mm2) and a higher chlorophyll content (31.1 SPAD Unit) were recorded from tip cuttings of P. zeylanicus. Furthermore, the topsoil: sand: compost-1:1:1 combination showed a higher survival percentage (90%), number of leaves (3), highest average plant height (43.9cm) and average root length (20.2 cm) with significantly (P<0.05) higher average leaf area (52.3 mm2) and chlorophyll content (31.07 SPAD Unit). Daily watering to the field capacity showed a higher survival percentage (90%), significantly higher (P<0.05) number of leaves (3.7), plant height (51.6 cm), higher root length (25.5 cm), the highest average leaf area (80.0 mm2) and chlorophyll content (32.7 SPAD Unit). Therefore, tip-cutting planted in topsoil: sand: compost-1:1:1 media can be recommended for successful propagation of P. zeylanicus. 2024-09-30T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/19338 Effect of coating chemically derived chitosan from shrimp shell wastes on physical, microbiological and sensory characteristics of chicken sausages Mithushan, P.; Pagthinathan, M.; Ravikumar, S.; Vahaful Nisath, M.F. Sausages have high moisture and protein content, making them extremely vulnerable to microbial deterioration. The antimicrobial qualities of chitosan coating prolong the shelf-life of sausages. The aim of this present study was to evaluate the effect of 0, 0.25, 0.5 and 1% (w/v) of chitosan coatings on microbiological, physical and sensory attributes of chicken sausages in cold storage (-10 °C). Chitosan was extracted from shrimp shell and dissolved in acetic acid to prepare 0.25, 0.5 and 1% of edible chitosan solution and control (0%). Sausages were coated by dipping in chitosan solutions. To find the best percentage of chitosan coating, physical, microbiological and sensory attributes were examined during the storage period. A number of TAB colonies was shown to have increased during the storage; nevertheless, the values were within the acceptable level (5.00 Log (CFU/g) in 0.25, 0.5 and 1% chitosan treated samples in two weeks of storage. The number of TAB colonies was not significantly (P>0.05) reduced between the samples treated with 0.25, 0.5 and 1% of chitosan. Further, hardness values were increased with the chitosan coating, while 1% chitosan-coated sausages had the highest value for hardness (27.93 N). Similarly, the WHC also increased with the chitosan coating. There was no significant difference observed (P>0.05) among 0.25, 0.5, and 1.0% of chitosan coating in WHC. pH values improved with the chitosan coating. Moisture and colour were not significantly (p>0.05) affected by chitosan coating. During storage, deteriorative changes occurred slowly in coated sausages. 1% chitosan coated sausages had the highest overall acceptability and maximum scores for odour, colour, taste, appearance and texture on the day 1 and 4th week of storage. Chitosan coating can be utilized as an edible coating material for the preservation of meat products. 2024-09-30T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/19333 Establishing protocols for glycaemic index clinical trials in an academic setting in Sri Lanka Nikalansooriya, N.M.A.I.; Somaratne, G.M.; Maithreepala, S.D.; Gunasekara, D.C.S.; Wijekoon, A.P.; Dahanayake, T.N.; Sandaruwan, N.B.L.; Karunarathna, H.K.A.T.; Madhumali, K.D.U.; Abeysiriwardena, D.S.D.Z.; Chandrasekara, A.; Prasantha, B.D.R. The University of Peradeniya in Sri Lanka has initiated a Healthy Human Clinical Trial Unit (CTU) dedicated to post-prandial glycaemic response (PPGR) analysis. The present study, involving 42 participants aged 22-25 years, assessed the glycaemic index (GI) of four rice varieties: Super Kernel, Rathu Suduru, Ceylon Purple, and Red Fragrant. The results identified GI values ranging from 40 to 61, categorizing these varieties into low and medium GI groups, with Super Kernel and Rathu Suduru representing the lowest (40 ± 5.5) and the highest (61 ± 5.5) GI values, respectively. Glycaemic load (GL) values ranged from 8 to 12, falling into low and medium categories. This pioneering initiative validates the effectiveness of CTU in precise GI and GL evaluation for food labelling, which are essential for informing consumers about how different types of food impact the sugar levels in the bloodstream. Also, it is a precedent for future clinical nutrition research, emphasizing the need for consistent and harmonized methodologies in academic and regulatory contexts to support broader public health goals by providing accurate nutritional information to consumers. The processes and standards are detailed in a comprehensive guidebook (ISBN 978-624-94637-0-7), supporting the continuation and expansion of further PPGR studies. 2024-09-30T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/19327 Impact of different soil amendments on Carbon and Nitrogen mineralization in ultisols Amarasinghe, S.R.; Premanath, K.P.S.D.; Wanniarachchi, S.D. Quantifying the nutrient mineralization in soils amended with different materials is vital for understanding the nutrient availability for plant uptake. It helps to improve nutrient management by minimizing nutrient loss from the soil. The present research was conducted as a laboratory incubation to assess the nitrogen (N) and carbon (C) mineralization in Ultisols amended with cattle manure, spent poultry layer litter, Gliricidia leaves (Gliricidia sepium), leaf litter compost, urea, and Siam weed leaves (Chromolaena odorata). A Completely Randomized Design (CRD) was used with four replicates, and means were compared with Duncan’s multiple range test (DMRT) after analyzing the data with the SPSS 25 statistical package. CO2-C evolution in amended soils increased up to day 14 of incubation and became stable as incubation progressed. The highest total flux of CO2-C (171.89 g/kg) was obtained in cattle manure-amended soil. Compost-amended soil showed significantly higher (p=0.05) release of mineralized nitrogen (1530.31 mg/kg) over unamended control. The pH in all the amended soils increased over time, with the highest pH in soil amended with compost. Thus, the present study indicated rapid C and N mineralization when different amendments are integrated into the soil. 2024-09-30T00:00:00Z