Badulla, Sri Lanka

Uva Wellassa University
Badulla, Sri Lanka

Uva Wellassa University is a Sri Lankan National University. The university was established by government gazette effective 1st of June, 2005 in Badulla, Sri Lanka as the 14th national university of Sri Lanka. President Chandrika Kumaratunga established the university in 2007. The university officially opened by Sri Lankan president Mahinda Rajapaksa on 5th of August, 2009.It is the first all-entrepreneurial university in Sri Lanka. It differs from other Sri Lankan universities, as it is designed to provide essential skills and broad general education for all students, while providing the conceptual and methodological background and the training to obtain practical solutions for value addition to the national resources base of Sri Lanka. Wikipedia.

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Sirimanne P.M.,Uva Wellassa University | Perera V.P.S.,Open University of Sri Lanka
Optik | Year: 2016

Dyes and pigments absorb unique portion of visible light. Solvatochromic behavior and formation of monomers and aggregations are characteristics features of dyes. Several types of dyes and pigments have been employed to study sensitization process of TiO2|sensitizer|p-semiconductor type solar cells. An enhancement of efficiency of this type of solar cells could be expected by appropriate coupling of several dyes as a result of fully coverage of visible spectrum. A comparable study of multi dye systems was carried compare to that of mono dye systems. © 2016 Elsevier GmbH.

Wijesekara K.B.,Uva Wellassa University | Iqbal M.C.M.,Sri Lanka Institute of Fundamental Studies
Scientia Horticulturae | Year: 2013

The induction of secondary embryos in androgenic and zygotic embryos of Datura metel (L.) (Solanaceae) was investigated by excising their shoot and root meristems and culturing the hypocotyls on Nitsch medium. Androgenic embryos produced secondary embryos on the hypocotyl. Histological sections showed secondary embryo development was independent of maternal tissue with no connection to the maternal vascular system. The zygotic embryos produced shoot buds and adventitious roots from the cut surface. Shoot buds had vascular connections with the maternal tissue. Excision of both meristems produced more secondary embryos than excision of the apical meristem alone. Excision of apical meristems in embryogenically competent immature embryos and their in vitro culture could potentially produce secondary embryos on the hypocotyls. The significance of these results is the clonal multiplication of the primary embryo at an early stage of embryo development. The meristem excision steps are easily performed under sterile conditions. © 2013 Elsevier B.V.

Jayasena D.D.,Chungnam National University | Jayasena D.D.,Uva Wellassa University | Jo C.,Seoul National University
Food Reviews International | Year: 2014

This review provides an overview of the published data on the antioxidative potentials of common essential oils and their components that could be considered suitable for application to meat and meat products. The positive effects of essential oils from oregano, rosemary, thyme, sage, basilica, ginger, and others, when used alone or in combination with other essential oils and/or as a part of hurdle technology to extend product shelf life by controlling lipid oxidation and improving the sensory qualities of meat and meat products, are well documented. Phenolic constituents of many of these essential oils act as free radical scavengers and hydrogen donators that prevent lipid oxidation. © 2014 Copyright Taylor and Francis Group, LLC.

Jayasena D.D.,Chungnam National University | Jayasena D.D.,Uva Wellassa University | Jo C.,Seoul National University
Trends in Food Science and Technology | Year: 2013

Production of safe and high quality meat and meat products along with recent consumer's demand for all-natural and clean-label is challenging. Plant-derived essential oils (EOs) have shown remarkable antimicrobial potency against spoilage and pathogenic microorganisms in meat and meat products. In this review, basics of microbial deterioration of meat and meat products and traditional preservation methods used are first discussed followed by mode of action and scope of application of EOs for these products. Application of EOs is partially limited due to their intense aroma but advanced technologies can be combined to improve both the microbial stability and sensory quality. © 2013 Elsevier Ltd.

Jayasena D.D.,Chungnam National University | Jayasena D.D.,Uva Wellassa University | Jung S.,Chungnam National University | Bae Y.S.,Chungnam National University | And 3 more authors.
Journal of Food Composition and Analysis | Year: 2015

A study was conducted to compare carnosine, anserine, betaine and carnitine contents of breast and leg (combined thigh and drumstick) meat from Korean native chickens (KNCs) and commercial broilers (CBs) at their market ages (100 and 32. d, respectively) and to determine the changes in these compounds during moist heat cooking. In general, KNCs showed significantly higher histidyl dipeptide and carnitine contents and a lower betaine content than CBs (p<. 0.05). Significantly higher histidyl dipeptide contents were observed in breast meat, while leg meat had more betaine and carnitine contents (p<. 0.05). Significant decreases in the content of all compounds analysed in this study occurred during cooking (p<. 0.05). Meat from KNCs is a good source of carnosine, anserine, and carnitine compared to that from CBs, which has a higher content of betaine. In addition, the contents of these endogenous compounds are significantly affected by the meat portion and the cooking process (p<. 0.05). © 2014 Elsevier Inc.

Abeyrathne E.D.N.S.,Uva Wellassa University | Lee H.Y.,Iowa State University | Jo C.,Seoul National University | Nam K.C.,Sunchon National University | And 2 more authors.
Poultry Science | Year: 2014

Ovalbumin is the predominant protein in egg white and is widely used in cell culture. However, it also can be used to produce peptides with various functional properties. The objectives of this study were to hydrolyze ovalbumin using various enzyme, incubation time, and temperature combinations, and to compare the functional properties of the hydrolysates. Ovalbumin (20 mg/mL) was hydrolyzed with 1% of pepsin, trypsin, α-chymotrypsin, papain, and alcalase, singly or in combination at 37°C, and then the enzymes were inactivated at 100°C for 15 min. Hydrolyzing ovalbumin with pepsin (OAPe), pepsin + papain (OAPePa), pepsin + alcalase (OAPeAl), alcalase + trypsin (OAAl-Tr), and α-chymotrypsin (OACh) was also effective in producing peptides from ovalbumin, and the peptides produced had strong iron- and copper-binding capacities and antioxidant capability. However, the best treatment of all was the OAAlTr treatment, which showed the highest iron-chelating and antioxidant activities among the enzyme treatments (P < 0.05). Electrospray-ionization mass spectrometry (MS/MS) analysis identified numerous peptides (<5 kDa) from the OAPe, OAPeAl, OACh, OAAlTr, and OAPePa hydrolysates of ovalbumin, but the number and size of peptides varied widely depending on the treatments. The enzymatic hydrolysis significantly increased the functionality of ovalbumin, and the improvement depended upon the composition of peptides produced rather than the number of the peptides produced. © 2014 Poultry Science Association Inc.

Ratnaweera P.B.,University of Colombo | Ratnaweera P.B.,University of British Columbia | Ratnaweera P.B.,Uva Wellassa University | Williams D.E.,University of British Columbia | And 3 more authors.
Organic Letters | Year: 2015

Solanioic acid (1), a degraded and rearranged steroid that exhibits in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), has been isolated from laboratory cultures of the fungus Rhizoctonia solani obtained from tubers of the plant Cyperus rotundus collected in Sri Lanka. The structure of solanioic acid (1) was elucidated by detailed analysis of NMR data, a single crystal X-ray diffraction analysis of a reduction product 2, and Mosher ester analysis on a derivative of the natural product. Solanioic acid (1) has an unprecedented carbon skeleton. © 2015 American Chemical Society.

Herath H.M.S.K.,Massey University | Herath H.M.S.K.,Uva Wellassa University | Camps-Arbestain M.,Massey University | Hedley M.,Massey University
Geoderma | Year: 2013

Improving soil physical properties by means of biochar application has been proposed in recent publications. The objective of this study was to investigate to what extent the addition of corn stover (CS) and biochars produced from the pyrolysis of corn stover feedstock (CS) at 350 and 550°C temperatures (CS-350, CS-550) affected aggregate stability, volumetric water content (θV), bulk density, saturated hydraulic conductivity (Ks) and soil water repellency of specific soils. Organic amendments (CS, CS-350, CS-550) were incorporated into a Typic Fragiaqualf (TK) and a Typic Hapludand (EG) soils at the rate of 7.18tCha-1, which corresponded to 17.3, 11.3 and 10.0tbiocharha-1 for the CS, CS-350 and CS-550 treatments, respectively. After 295d of incubation (T295), soils were sampled as (i) undisturbed samples for bulk density and Ks; and (ii) mildly disturbed samples for θV (at -15, -1, -0.3, -0.1, -0.08, -0.06, -0.04, and -0.02bar), aggregate stability and soil water repellency. The θV at time 0 (T0) was also determined at -15, -1 and -0.3 matric potentials for the different treatments. Biochar application significantly increased (P<0.05) aggregate stability of both soils, the effect of CS-550 biochar being more prominent in the TK soil than that in the EG soil, and the reverse pattern being observed for the CS-350 biochar. Biochar application increased the θV at each matric potential although the effect was not always significant (P<0.05) and was generally more evident in the TK soil than that in the EG soil, at both T0 and T295. Biochar addition significantly (P<0.05) increased the macroporosity (e.g., increase in θV at -0.08 to 0bar) in the TK soil and also the mesoporosity in the EG soil (e.g., increase in θV from -1 to -0.1bar). Both biochars significantly increased (P<0.05) the Ks of the TK soil, but only CS-350 biochar significantly increased (P<0.05) the Ks in the EG soil. Biochar was not found to increase the water repellency of these soils. Overall results suggest that these biochars may facilitate drainage in the poorly drained TK soil. However, the present results are biochar-, dose- and soil-specific. More research is needed to determine changes produced in other biochar, dose and soil combination, especially under field conditions. © 2013 Elsevier B.V..

Ratnaweera P.B.,University of Colombo | Ratnaweera P.B.,Uva Wellassa University | Williams D.E.,University of British Columbia | de Silva E.D.,University of Colombo | And 3 more authors.
Mycology | Year: 2014

An endophytic fungus was isolated from surface sterilized leaf segments of Anoectochilus setaceus, an orchid endemic to Sri Lanka, and was identified as Xylaria sp. by morphological characters and DNA sequencing. Bioassay-guided chromatographic fractionation of the organic extract of a laboratory culture of this fungus led to the isolation of the known antibacterial helvolic acid. Helvolic acid was active against the Gram-positive bacteria, Bacillus subtilis [minimal inhibitory concentrations (MIC), 2 μg mL-1] and methicillin-resistant Staphylococcus aureus (MIC, 4 μg mL-1). © 2014 © 2014 The Author(s). Published by Taylor & Francis.

Yaghini N.,Chalmers University of Technology | Pitawala J.,Uva Wellassa University | Matic A.,Chalmers University of Technology | Martinelli A.,Chalmers University of Technology
Journal of Physical Chemistry B | Year: 2015

We report on the effect of water on local structure and phase behavior of two protic ionic liquids, C2HImTFSI and C2HImTfO. Raman and infrared spectroscopy are employed to investigate the local coordination state. We find that water interacts weakly with TFSI- while more speci fically with TfO- through the -SO3 group. Additionally, we observe that upon addition of water the -NH stretching frequency does not change in C2HImTFSI, while it red-shifts in C2HImTfO, indicative of different hydrogen bonding configurations. Supported by the appearance of some additional features in the 800-1000 cm-1 frequency range where ring out-of-plane bending (γ) modes are found, we hypothesize that in C2HImTFSI water interacts only with the cation coordinating to the ring C2H and the N3H sites, while it interacts with both cation and anion in C2HImTfO forming hydrogen bonds that involve the cationic N-H site as well as the anionic -SO3 group. These different local structures also reflect in the phase behavior investigated by DSC, which reveals a more homogeneous solution when water is added to C2HImTfO, as compared to H2O/C2HImTFSI mixtures. Finally we report that the addition of water also significantly affects both Tm and Tg. (Chemical Equation Presented). © 2014 American Chemical Society.

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