• Member-Sri Lanka Association for the Advancement of Science
• Member-Institute of Biology, Sri Lanka
• Member-Sri Lankan Association of Young Scientists

Valorization of fruit peel waste, dairy science, food product development, functional foods

• Fish consumption patterns of Veddas in Sri Lanka (Collaborative research with Faculty of Animal Sciences, Uva Wellassa University)
• Animal studies for herbal beverages (Collaborative research with Faculty of Indigenous Medicine, University of Colombo)
• Food product development for diabetic patients (a collaboration of food industries in Sri Lanka)
• Assess the calorie intake and physical activity of adolescents in Sri Lanka and Indonesia (collaboration with the Department of Food Science and Nutrition, Wayamba University of Sri Lanka; Faculty of Medicine, University of Sumatera Utara, Indonesia and Lovely Professional University of India)

Full papers publications in Q1  journals

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R. M. U. S. K., 2020. Chemical Composition, Physicochemical and Technological Properties of Selected Fruit Peels as a Potential Food Source. International Journal of Fruit Science, 20(2), pp.1–12.

Dias, P. G. I., Sajiwani, J. W. A., and Rathnayaka, R. M.U.S.K., 2020. Consumer perception and sensory profile of probiotic yogurt with added sugar and reduced milk fat. Heliyon, 6(7), e04328.

Full papers publications in Q2/Q3  journals

Dias, P.G.I., Marapana, R.A.U.J., Rathnayaka, R.M.U.S.K., Gayathri, S.M.D.S., Anuradha, N.G.D., Kananke, T.C., Rathnayaka, R.M.K.T., Perera, M.G.A.N., Sabaragamuwa, R.S. and Wickramaratne, N.M., 2024. Identification of the best plant ratios for a polyherbal tea mix to obtain optimum antioxidant, antidiabetic, and β-glucuronidase inhibition activities. Journal of Ayurveda and Integrative Medicine, 15(5), 101053.

Dias, P.G.I., Marapana, R.A.U.J., Rathnayaka, R.M.U.S.K., Gayathri, S.M.D.S., Anuradha, N.G.D., Kananke, T.C., Rathnayaka, R.M.K.T., Perera, M.G.A.N., Sabaragamuwa, R.S. and Wickramaratne, N.M., 2023. Consumers' Knowledge, Attitudes, and Behavior Regarding Functional Food Products-A Survey from Selected Areas of Sri Lanka. Journal of Agricultural Sciences (Sri Lanka), 18(1).

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R.M.U.S.K., 2020. Optimization of the functional characteristics of composite fruit peel powder for incorporate into fat and sugar free probiotic set yoghurt, The Journal of Agricultural Sciences, 16(2), pp. 226-236.

Full papers/Review articles publications in other indexed journals

Dias, P.G.I., Marapana, R.U.J. and Rathnayaka, R.M.U.S.K., 2023. Production and quality evaluation of herbal tea mixtures from Phyllanthus Debilis, Osbeckia octandra, and Artrocarpus heterophyllus leaves. Sumatera Medical Journal, 6(3), pp.198-207.

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R.M.U.S.K., 2020. A Study on Fruit Wastage in Mass Scale Fruit Processing Industries in Sri Lanka and their Potential to Reuse. Food science and Nutrition Research, 3(1), pp.1-6.

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R.M.U.S.K., 2020. Formulation and development of composite fruit peel powder incorporated fat and sugar-free probiotic set yogurt. GSC Biological and Pharmaceutical Sciences, 11(1), pp. 93–99.

Dias, P.G.I., Sajiwanie, J.W.A., and Rathnayaka, R.M.U.S.K., 2020. Alteration of Basic Quality Attributes of Set Yogurts as Added Sugar and Milk Fat Reduction. Asian Food Science Journal, 17(1), pp. 24–37.

Imanthika Dias, P.G. and Niroshan Jayasooriya, M.C., 2017. Enhancing the Physiochemical and Antioxidant Properties of Stirred Yoghurt by Incorporating Soursop (Annona muricata). International Journal of Life Sciences Research, 5(1), pp. 69-77.

Dias, P.G.I., Rathnayaka, R., 2020. Transmission, Stability, Symptoms, Diagnosis and Management of COVID 19. Asian Journal of Research in Infectious Diseases. 4(1), pp.39–47.

Dias, P.G.I. and Rathnayaka, R.M.U.S.K., 2018. Alteration of Quality Attributes in Yoghurts as a Function of Natural Fibers Incorporation, Elixir Food Science,131, pp. 53231-53237

Dias, P.G.I. and Rathnayaka, R.M.U.S.K.,2018. Fluorescence in situ hybridization (FISH) in Food Pathogen Detection. International Journal of Molecular Biology, 3(3), pp. 143‒149.

Full papers publications in Q1  journals

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R. M. U. S. K., 2020. Chemical Composition, Physicochemical and Technological Properties of Selected Fruit Peels as a Potential Food Source. International Journal of Fruit Science, 20(2), pp.1–12.

Dias, P. G. I., Sajiwani, J. W. A., and Rathnayaka, R. M.U.S.K., 2020. Consumer perception and sensory profile of probiotic yogurt with added sugar and reduced milk fat. Heliyon, 6(7), e04328.

Full papers publications in Q2/Q3  journals

Dias, P.G.I., Marapana, R.A.U.J., Rathnayaka, R.M.U.S.K., Gayathri, S.M.D.S., Anuradha, N.G.D., Kananke, T.C., Rathnayaka, R.M.K.T., Perera, M.G.A.N., Sabaragamuwa, R.S. and Wickramaratne, N.M., 2024. Identification of the best plant ratios for a polyherbal tea mix to obtain optimum antioxidant, antidiabetic, and β-glucuronidase inhibition activities. Journal of Ayurveda and Integrative Medicine, 15(5), 101053.

Dias, P.G.I., Marapana, R.A.U.J., Rathnayaka, R.M.U.S.K., Gayathri, S.M.D.S., Anuradha, N.G.D., Kananke, T.C., Rathnayaka, R.M.K.T., Perera, M.G.A.N., Sabaragamuwa, R.S. and Wickramaratne, N.M., 2023. Consumers' Knowledge, Attitudes, and Behavior Regarding Functional Food Products-A Survey from Selected Areas of Sri Lanka. Journal of Agricultural Sciences (Sri Lanka), 18(1).

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R.M.U.S.K., 2020. Optimization of the functional characteristics of composite fruit peel powder for incorporate into fat and sugar free probiotic set yoghurt, The Journal of Agricultural Sciences, 16(2), pp. 226-236.

Full papers/Review articles publications in other indexed journals

Dias, P.G.I., Marapana, R.U.J. and Rathnayaka, R.M.U.S.K., 2023. Production and quality evaluation of herbal tea mixtures from Phyllanthus Debilis, Osbeckia octandra, and Artrocarpus heterophyllus leaves. Sumatera Medical Journal, 6(3), pp.198-207.

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R.M.U.S.K., 2020. A Study on Fruit Wastage in Mass Scale Fruit Processing Industries in Sri Lanka and their Potential to Reuse. Food science and Nutrition Research, 3(1), pp.1-6.

Dias, P. G. I., Sajiwanie, J. W. A., and Rathnayaka, R.M.U.S.K., 2020. Formulation and development of composite fruit peel powder incorporated fat and sugar-free probiotic set yogurt. GSC Biological and Pharmaceutical Sciences, 11(1), pp. 93–99.

Dias, P.G.I., Sajiwanie, J.W.A., and Rathnayaka, R.M.U.S.K., 2020. Alteration of Basic Quality Attributes of Set Yogurts as Added Sugar and Milk Fat Reduction. Asian Food Science Journal, 17(1), pp. 24–37.

Imanthika Dias, P.G. and Niroshan Jayasooriya, M.C., 2017. Enhancing the Physiochemical and Antioxidant Properties of Stirred Yoghurt by Incorporating Soursop (Annona muricata). International Journal of Life Sciences Research, 5(1), pp. 69-77.

Dias, P.G.I., Rathnayaka, R., 2020. Transmission, Stability, Symptoms, Diagnosis and Management of COVID 19. Asian Journal of Research in Infectious Diseases. 4(1), pp.39–47.

Dias, P.G.I. and Rathnayaka, R.M.U.S.K., 2018. Alteration of Quality Attributes in Yoghurts as a Function of Natural Fibers Incorporation, Elixir Food Science,131, pp. 53231-53237

Dias, P.G.I. and Rathnayaka, R.M.U.S.K.,2018. Fluorescence in situ hybridization (FISH) in Food Pathogen Detection. International Journal of Molecular Biology, 3(3), pp. 143‒149.

Abstract publications at international foreign conferences and symposiums

Oral presentations

Mohamed Shafras and Gayani Imanthika Dias, knowledge among adult Sri Lankans about the spread of covid 19, 4^th International Conference on Tropical Medicine and Infectious Diseases, Indonesia. PP. 139

P. Gayani I. Dias, R.A. Upul J. Marapana, and R.M. Udaya S.K. Rathnayaka, Identification of the best plant ratios for a polyherbal tea mix to Obtain optimum antioxidant, antidiabetic, and β-glucuronidase Inhibition activities, 4^th International Conference on Tropical Medicine and Infectious Diseases, PP. 304

Dias, P.G.I., Anuradha, N.G.D., Somathunga, C., Perera, M.G.A.N., Rathnayaka, R.M.K.T., Kananke, T.C., Wickramarathne, M.N., and Rathnayaka, R.M.U.S.K., 2020. Garcinia cambogia and Camellia sinensis; a promising synergy for weight loss herbal tea formulations. 28^th International Conference of Functional Food Center, USA (Online)

Jayasena, N., Dias, P.G.I., Anuradha, N.G.D., Somathunga, C., Perera, M.G.A.N., Rathnayaka, R.M.K.T., Kananke, T.C., Wickramarathne, M.N., and Rathnayaka, R.M.U.S.K., 2020. Evaluation of effect of Fadna Easy Tea (FET) consumption on relieving menstrual pain and discomfort in female adolescents using human model. 28^th  International Conference of Functional Food Center, USA (Online)

Anuradha, N.G.D., Dias, P.G.I., Somathunga, C., Perera, M.G.A.N., Rathnayaka, R.M.K.T., Kananke, T.C., Wickramarathne, M.N., and Rathnayaka, R.M.U.S.K., 2020. Review the immunological functions of the ingredients of ‘‘Fadna Immunni Tea”. 28^th International Conference of Functional Food Center, USA (Online)

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2019. A Study on Fruit Wastage in Mass Scale Fruit Processing Industries in Sri Lanka and Their Potential to Reuse. Conference on Food Science and Nutrition, Rome, Italy

Illangasinghe, S., Wijerathne, A., Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2019. Growth Stimulation of Bifidobacterium bifidum by Tourmaline. Conference on Food Science and Nutrition, Rome, Italy

Poster presentation

P. Gayani I. Dias, R.A. Upul J. Marapana, and R.M. Udaya S.K. Rathnayaka, production and quality evaluation of herbal tea mixtures from Phyllanthus debilis, Osbeckia octandra, and Artrocarpus heterophyllus leaves, 4^th International Conference on Tropical Medicine and Infectious Diseases, Indonesia. PP. 303

Abstract publications at international/national local conferences and symposiums

W.M.R.S. Kumara, R.M.S. Gunathilaka, and P.G.I. Dias, Physiochemical, Functional, and Sensory Properties of Soy Milk in Compared to Full Cream, and Skimmed Milk in Instant Tea Powder, Ruhuna University Faculty of Allied Health Sciences International Research Symposium - iRuFARS 2024, 5^th July 2024.

Dias P.G.I., Rathnayaka, R.M.U.S.K. and Marapana, R.A.U.J., 2023. In vitro antioxidant and antidiabetic activity of herbal infusions, national symposium on agro-technology and rural sciences (NSATRS - 2023), PP. 19

Perera, M.G.A.N., Anuradha, N.G.D., Gayathri, S.S.M., Rasangani,  A.W.P., Dias, P.G.I, Sabaragamuwa, R., Kananke, T.C., Rathnayake, R.M.K.T., Wickramaratne, M.N. and Rathnayake, R.M.U.S.K., 2022. Isolation and structure characterization of a hypoglycemically active flavone glycoside from Sri Lankan green leafy vegetable Olax zeylanica (Malla), Annual Scientific Session, Sri Lanka Association for the Advancement of Science (SLAAS), PP. 79

Wickramasinghe M.A., Dias P.G.I., Anuradha N.G.D., Kananke T.C.,Perera M.G.A.N., Rathnayaka R.M.K.T.,Sabaragamuwa R.S. , Wickramarathne M.N. and Rathnayaka R.M.U.S.K. (2021), A Ready-Meal Functional Soup Mix Supplemented with Potential Antidiabetic Herbs, Peradeniya University International Research Sessions 2021, Sri Lanka,Vol. 23, pp.161

Wijekoon W.M.A.N., Gayathri S.M.D.S., Dias P.G.I., Anuradha N.G.D., Kananke T.C., Perera M.G.A.N., Rathnayaka R.M.K.T., Sabaragamuwa R.S., Wickramarathne M.N. and Rathnayaka R.M.U.S.K., Antimicrobial activity of selected plant extracts against Salmonella typhi and Escherichia coli and their phytochemical screening, International Conference on Applied and Pure Sciences-2021, Faculty of Science, University of Kelaniya, Sri Lanka, pp. 13.

Ranasinghe M.M.K.D, Gayathri S.M.D.S., Dias P.G.I., Anuradha N.G.D., Kananke T.C., Perera M.G.A.N., Rathnayaka R.M.K.T., Sabaragamuwa R.S., Wickramarathne M.N. and Rathnayaka R.M.U.S.K., Physicochemical, techno-functional and hypoglycemic properties of selected wheat flour substitutes, International Conference on Applied and Pure Sciences-2021, Faculty of Science, University of Kelaniya, Sri Lanka,pp 105.

Wijerathna J.A.D.O.S, Dias P.G.I., Anuradha N.G.D., Gayathri S.M.D.S., Perera M.G.A.N., Kananke T.C., Rathnayaka R.M.K.T., Sabaragamuwa R.S., Wickramarathne M.N., Rathnayake R.M.U.S.K., Optimization of brewing time and temperature for improving total phenolic content and antioxidant activity in Passiflora foetida L. tea using response surface methodology, 06th International Conference on Ayurveda Traditional Medicine and Medicinal Plants, GARI RESEARCH SYMPOSIUM 2020

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., Awolu,O.O., 2020, Optimization of the Functional Characteristics of Composite Fruit Peel Powders as a Promising Texture Modifier in Fat Free Set Yoghurts. World Food congress, Auckland,New Zeland (Accepted)

Dias, P.G.I., Anuradha, N.G.D., Somathunga, C., Dasanayaka, P.D.S.D., Perera, M.G.A.N., Rathnayaka, R.M.K.T., Kananke, T.C., Wickramarathne, M.N., and Rathnayaka, R.M.U.S.K. 2019. Requirement Analysis for Identifying the Commercializing Potential of an Herbal Remedy for the Treatment of Dysmenorrhea. 7^th  International Conference of Sabaragamuwa University of Sri Lanka. pp 21

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2019, Potential Application of Fruit Peel Powders as Texture Modifiers and Functional Ingredients in Fat And Sugar Free Probiotic Set Yoghurt, SLAYS international conference,.pp 12

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2018, Effect of Milk Fat and Added Sugar Reduction on the Sensory Properties and Consumer Acceptability of Probiotic Set Yoghurts. 8^th   annual Research Session of Sabaragamuwa University of Sri Lanka, pp. 30

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2019, Investigation of Functional Properties and Phytochemical Screening of Selected Fruit peel powders, 3rd International Research Symposium, Uwa Wellassa University, Sri Lanka, pp. 320

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2018, Chemical composition, physicochemical and technological properties of selected fruit peels, South Asian Conference on multidisciplinary Research, pp. 30

Dias, P.G.I., Sajiwanie, J.W.A. and Rathnayaka, R.M.U.S.K., 2018, Influence of Milk Fat and Added Sugar Content on Texture Profile of Set Yoghurts. 2nd International Research Symposium, Uwa Wellassa University, Sri Lanka, pp. 320

Dias, P.G.I. and Jayasooriya M.C.N., 2017, Soursop Juice and Nectar Incorporated Stirred Yoghurts with Enhanced Physiochemical and Antioxidant Properties. Annual Scientific Session of the Nutrition Society of Sri Lanka, pp. 2

Dias, P.G.I., Somawathie, K.M., Abeysekara, W.K.S.M. and Premakumara, G.A.S., 2016. Low Fat Low Sugar and No Sugar Rice Extract Incorporated Yoghurts with Enhanced Physiochemical and Antioxidant Properties, Abstracts Book of Final Year Research Project Presentations, Department of Food Science and Technology, SUSL, pp.3

LHPS Wijerathne, PCB Dias, EPDN Thilakarathne, PGI Dias, NPR Deyshappriya, An Overview on Behaviors of Fishing, Fish Consumption and Preservation Techniques of Indigenous Community in Sri Lanka. With Special Reference to ‘Dambana’Indigenous Community, 5th International Research Symposium, Uwa Wellassa University, Sri Lanka, pp. 55

Wijesekara ERJMDDP, Amarasinghe AMPC, Dayasena YAPK, and Dias PGI (2023) Base Catalyst De-polymerization of Rice Straw Lignin to produce Phenol Monomers. 1st International Research Conference, Faculty of Technology, Eastern University

• National Awards for Excellence in Agriculture Research in Sri Lanka, December 2024
• Travel award-4^th International Conference on Tropical Medicine and Infectious Diseases (4^th ICTROMI), Indonesia, September 2023
• 1^st  Runner-Up, All Island Three Minute Thesis Presentation Competition (3MT) among MPhil and PhD Students, Organized by Sri Lanka Association of Young Scientists (SLAYS), October 2019
• Best Oral Presenter at 3^rd International Research Conference on Uva Wellassa University of Sri Lanka, February 2019
• ‘Professor Indrarathne Balasooriya Memorial Gold Medal’ for the Best Performance with the Highest GPA in the Department of Food Science and Technology at the 18th General Convocation of Sabaragamuwa University of Sri Lanka, December 2016

International patent

Herbal beverage from Annona muricata extract and method of preparation thereof. PCT/IB2022/050937 – PCT published.

National patents

An herbal tea formulation for diabetic patients, Patent No: 21327
A soup mix with anti-diabetic activity, Patent No: 21328
A method for formulating soursop-based medicated wine with anti-diabetic activity, Patent No: 21884