Browsing by Author "Jayasinghe, U.L.B."

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Development of a Wine from Tamarind (Tamarindus indica), a Value Added Product from an Underutilized Fruit Crop in Sri Lanka
    (Uva Wellassa University of Sri Lanka, 2010) Marasinghe, M.M.N.K.; Jayasinghe, U.L.B.; Wimalasiri, K.M.S.
    Tamarind (Tamarindus indica) is an underutilized fruit crop in Sri Lanka which has a greater potential towards food product development. A trial to develop wine with baker's yeast instead of the wine yeast was attempted. As the initial step suitable workable tamarind pulp: water ratios were selected as 1:07, 1:08, 1:09 and 1:10 and the pH and Total soluble solid levels were adjusted as optimum for both wine yeast and baker's yeast and allowed for fermentation for one month. Alcohol content determined using embiliometer in wine, prepared using wine yeast and baker's yeast suggested that the wine sample prepared using wine yeast was significantly higher (p<0.05), while the sample with 1:09 tamarind pulp: water ratio fermented using wine yeast was significantly lower (p<0.05). Wine samples prepared using two different yeast types were compared for anti-oxidant activity using ascorbic acid as the reference. According to the results, quality of the wine yeast incorporated wine was significantly higher (p<0.05). Among the pulp: water ratio series, the sample 1:09 sample which was fermented using wine yeast was significantly higher (p<0.05) from among other samples. Sensory analysis was conducted to asses the consumer preference of the prepared wine samples using wine yeast and different pulp: water ratios (1:07, 1:08, 1:09, and 1:10). The results indicated that the consumer preference was not significant (p<0.05) for the odor, color and overall acceptability, but was significant (p<0.05) for the flavor of the wine. Among the concentration series 1:09 pulp: water ratio was significantly higher (p<0.05). In the sensory analysis of the baker's yeast fermented tamarind pulp samples, a significant difference (p<0.05) for color and odor was observed but it was not significant (p<0.05) for flavor and overall acceptability. Among the samples 1:07 pulp: water sample was significantly higher (p<0.05) in comparison to the others. Comparison of the best wine yeast fermented wine (1:09 pulp: water ratio) sample and baker's yeast fermented wine (1:07 pulp: water ratio) sample were compared with each other. According to the results, wine prepared using wine yeast with 1:09 tamarind pulp: water, showing 8.3 % alcohol and 99.61 % anti-oxidant content can be recommended as the optimized wine for the consumers. Key words: Wine, Yeast, Fermentation
  • No Thumbnail Available
    Item
    Search for Bioactive Compounds from Endophytic Fungi Isolated from the Leaves of Artocarpus heterophyllus Lam.
    (Uva Wellassa University of Sri Lanka, 2010) Ekanayaka, W.M.S.M.; Jayasinghe, U.L.B.
    Endophytes are a novel and potential source of modern medicine, agriculture and industry. As the structurally diverse and biologically active secondary metabolites possessing rich source the endophytic fungi have gained increased attention in the last decade. Endophytic fungi are the fungi, which colonize plants internally without apparent adverse effects and found in plants. The relationship between the endophyte and its host plant may range from mutualistic symbiosis to latent phytopathogenesis. Here we report the isolation of three endophytic fungi from the leaves of A. heterophyllus and the phytotoxicity of one of the crude extract of fungal toxins produced in the media of rice. Artocarpus heterophyllus in family Moraceae is widely distributed in tropical countries of Asia. In addition to the use of fruit as a staple food, various parts of the plant have been used in the traditional medicine, Infected leaves and healthy leaves of the A. heterophyllus were collected from the Institute of Fundamental Studies premises in Kandy. Three fungal colonies were isolated on PDA media. Out of three fungi, one fungus was selected for further studies since it was found in both healthy and diseased leaves of A. heterophyllus. A pure culture of fungus was inoculated in solid media of rice. After four weeks of growth, solid media were ground and extracted successively with organic solvents n-hexane, ethyl acetate and methanol in room temperature. Solvents were evaporated to dryness. Bioassays were conducted to detect antioxidant activity against DPPH (Diphenyl picryl hydrazyl) using spectrophotometry method and phytotoxicity against Lactuca sativa. None of the crude fungal extracts displayed significant antioxidant activity while ethyl acetate extract showed significant inhibition of Lettuce seeds shoot germination at 1000 ppm level concentration. Hence the crude ethyl acetate extract is a potential candidate for the isolation of natural phytotoxic compounds. Keywords: Endophytic fungus, Artocarpus heterophyllus Lam., phytotoxicity
  • No Thumbnail Available
    Item
    Structure modification of mefenamic acid and evaluate their bioactivities
    (Uva Wellassa University of Sri Lanka, 2015) Jayamaha, J.M.S.S.; Ediriweera, E.P.S.K.; Jayasinghe, U.L.B.; Kumar, N.S.
    Thousands of years medicine and natural products have been closely linked through the use of traditional medicines and natural poisons (Phillipson et al., 2001). Lately, pharmaceutical industries mainly pay their attention on natural products and their bioactivities to develop novel drugs which shows promising activities on diseases in humans as well as in plants. Since biological assays are used to detect the biological activity on synthetic compounds and natural products. There are several kinds of bioassays such as, antioxidant, antifungal, phytotoxicity, cytotoxicity and enzyme inhibitory activities (e.g. lipase, α-amylase, α-Glucosidase etc). Though there are several types of bioassays, most pharmaceutical manufacturing industries limited their research activities only towards one or few types of bioassays. There can be hidden bioactivities which are important in medicinally, agriculturally and environmentally. Therefore it is important to study about the other bioactivities too by doing the structure modifications of existing drugs and evaluate their bioactivities using various types of bioassays. By doing the modification of the exiting drug that can be enhanced the efficiency of the drug usage. Mefenamic acid (MFA) which is used as a pain killer from many years ago. It is a Non-Steroidal Anti- Inflammatory Drug (NSAID) which exhibits poor water solubility properties (Dixit et al., 2012). MFA is a prescription medicine used for the relief of mild to moderate pain, including painful menstrual periods (Asl et al., 2008). There can be some hidden important bioactivities which were not studied yet in addition as a pain-killer. The aim of this study was to improve the usages of the drug for industrially, agriculturally and environmentally. Therefore the drug was synthetically modified by acetylation/acylation reaction methods. Methodology Pure MFA was separated from the tablet by using column chromatography technique. Separated pure MFA was subjected to acetylation and acylation reactions according to Arnold et al., 2007. Acylation was carried out with acid chlorides such as acetyl chloride (AC), benzoyl chloride (BC) and crotonoyl chloride (CC), while acetylation with acetic anhydride. Efficiency of the drug and its synthetic derivatives were tested by subjecting to bioassays such as α-amylase inhibition assay (Giancarlo et al., 2006), antioxidant assay (DPPH radical scavenging assay) (Mensor et al., 2001), phytotoxicty (bio-assay with lettuce seed germination) (Drewes et al., 1995) and cytotoxicity (brine shrimp lethality assay) assay using Artemia salina (Subbaraju et al., 2005). The Inhibition percentage was plotted against the sample concentration and the fitted line plot was established. Then IC50value (Inhibitory Concentration) was calculated in order to the 50% inhibition.