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Item A NEW ANTIOXIDANT ACTIVE COMPOUND FROM THE ENDOLICHENIC FUNGUS, PENICILLIUM CITRINUM INHABITING THE LICHEN, PARMOTREMA SP(International Journal of Pharmaceutical Sciences and Research, 2019) Wickramarachchi, S.A.; Samanthi, U.; Wijeratne, K.; Paranagama, P.A.Context: Endolichenic fungi are the microorganisms living inside the thalli of the lichen and found to be a new source of bioactive secondary metabolites. This is an underutilized source of bioactive compounds and has not been studied extensively. Genus, Parmotrema is one of the foliose lichens with largely rounded lobes and occurs on rocks of rain forests, sub-montane and montane forests in Sri Lanka. Aims: The endolichenic fungi available in Sri Lanka and the chemistry of their secondary metabolites have not been explored thoroughly. This study aims at exploring novel bioactive compounds available in Penicillium citrinum inhabiting Parmotrema sp. Methods and Material: The lichen, Parmotrema sp., was collected from Hakgala Botanical Garden in Sri Lanka and its fungal strains were isolated and identified by Genomic DNA sequencing. Compounds were first extracted to ethyl acetate and subsequently subjected to bioassay-guided fractionation to isolate the bioactive compounds. The DPPH assay was used to determine the antioxidant activity. The active compound/s was separated by column chromatography, and its structure was elucidated by IR, 1D and 2D-NMR, 13C-NMR and MS. Statistical Analysis Used: The IC50 of the crude extract was calculated using Probit analysis (MINITAB® Release 14.1. Minitab Inc. 2003 Statistical Software). Results: A bioactive compound, named PP-PC-03 together with PP-PC-01 and PP-PC-02 was isolated from P. citrinum. All three compounds showed antioxidant activity in the DPPH assay with IC50 values 159.6 ± 22.3, 120.1 ± 11.7 and 68.6 ± 4.3 μg/mL respectively. Conclusion: Based on spectral analysis the structure of PP-PC-03was determined as 10-Ethylidene-2,4,9-trimethoxy-10,10a-dihydro-7,11-dioxa-benzo[b] heptalene-6,12-dione and identified as a new compound. Comparatively PP-PC-02 and PP-PC-03 had moderate antioxidant activities while PP-PC-01 showed strong radical scavenging activity.Item Evaluation of anti-inflammatory and antioxidant properties of Genus Piper in Sri Lanka. International Research Symposium on Pure and Applied Sciences,(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Athapattu, R.S.K.; Jayarathna, S.P.N.C.; Paranagama, P.A.; Senanayake, S.P.In Sri Lanka, the genus Piper is represented by ten species including five wild and two cultivated species. Most of the species of the genus Piper are important as medicinal plants and used in various systems of medicine.This study aims to evaluate the bioactivity (anti-inflammatory and antioxidant properties) of the selected five Piper spp. (P. nigrum L., P. longum L., P. betle L., P. chuvya (Miq.) and P. sylvestre). Specimens of leaves and fruits were collected from their natural habitats and cultivations, and were subjected to the extraction of essential oils by steam distillation. Three replicates were done for each concentration and data were analyzed using the MINITAB 17 statistical package. Antioxidant activity was tested using 2,2-diphenyl-1- picrylhydrazyl (DPPH) free radical scavenging assay and ferric reducing antioxidant power assay. The isolated essential oils of Piper species exhibited remarkable DPPH free radical scavenging ability at different concentrations. The results revealed that the essential oil of P.betle exhibited the highest radical scavenging activity (92.8% at 1 mg/mL) and the value is higher than even of the standard, Butylated Hydroxy Toluene (BHT), (74.5% at 1 mg/mL). Further, essential oils of P. chuvya and P. longum have shown 91.8% and 63.1%inhibition percentages at 1 mg/mL. Essential oil isolated from P. betle has showed remarkable ferric reducing antioxidant power (mean absorbance, 1.89at 1 mg/mL) compared to the standard, BHT, (2.01at 1 mg/mL). Further, it was observed that its antioxidant activity increased with the increment of the concentration of essential oil (0.03-1 mg/mL). These results suggested the potential of using essential oils of leaves of P.betle, P. chuvya (1.31) and P. longum (1.28) as sources of natural antioxidants. This study also focused on evaluating anti-inflammatory activity by using Human Red Blood Cell (HRBC) membrane stabilizing method.Higher mean inhibition percentage was observed for the essential oil of P. betle leaves (79.6%at 1 mg/mL) compared to the standard (aspirin) and the activity significantly increased with higher concentrations (76.4% at 0.5 mg/mL and 79.6% at 1 mg/mL). Further, 62 % and 58.3 % of inhibitions percentages were shown by essential oils of P. chuvya and P. longum respectively. According to the findings of this study, bioactivity properties of the leaves and fruits of these Piper species can be used in future perspectives for developing novel pharmaceuticals.Item A new curvularin macrolide from an endolichenic fungus, Curvularia trifolii, isolated from Usnea sp., in Sri Lanka(University of Kelaniya, 2014) Samanthi, U.; Wickramarachchi, S.; Paranagama, P.A.