Chathuranga, S. M. N.Rajapakse, C. S. K.2024-11-252024-11-252024Chathuranga S. M. N.; Rajapakse C. S. K. (2024), Comparison of photoprotective properties and anti-diabetic properties of pink colour and yellow colour flowers of Mirabilis jalapa Linn, Proceedings of the International Conference on Applied and Pure Sciences (ICAPS 2024-Kelaniya) Volume 4, Faculty of Science, University of Kelaniya Sri Lanka. Page 45http://repository.kln.ac.lk/handle/123456789/28789Herbal medicines are considered as the core of traditional treatment methods worldwide. Plants rich in phytochemicals exhibit a wide range of medicinal applications. Mirabilis jalapa is one such plant that exhibits a wide range of therapeutically valuable properties such as antioxidant, anti-inflammatory, antimicrobial, and anti-diabetic properties. Due to limited research on the bioactivities of Mirabilis jalapa flowers, this study aims to examine the photoprotective and anti-diabetic properties of yellow and pink color flowers. The total tannin content (TTC) of the flowers was also assessed as tannins are frequently utilized in the pharmaceutical and cosmetic industries due to their astringent, antioxidant, and anticancer properties. First, the chemical constituents of air-dried yellow and pink-colored flowers were separately extracted into methanol by cold maceration. Then the photoprotective properties, antidiabetic activity, and TTC of yellow color flower extract (YCFE) and pink color flower extract (PCFE) were analyzed by determining the sun protection factor (SPF), alpha-amylase inhibitory assay, and acidified vanillin method respectively. The SPF values of PCFE, YCFE, and commercially available sunscreen were 18.92 ± 0.63, 19.45 ± 0.54, and 31.47 ± 1.15 respectively. However, no alphaamylase inhibitory activity was observed for either PCFE or YCFE. Kanakamani et al., 2018 have reported that there is an alpha-amylase inhibitory activity in the ethanolic extract of Mirabilis jalapa flowers (IC50 = 430.09 ± 2.09 µg/mL). TTC values of YCFE and PCFE were 14.61 ± 0.32 and 12.83 ± 0.30 mg of catechin equivalent/g of the dry weight of the extract. The results indicated that the yellow flowers of Mirabilis jalapa exhibit higher tannin content than the pink flowers. Since the two extracts exhibit SPF values ranging between 15–30, both extracts showed moderate protection against UV radiation, hence they have the potential to be used as additives in sun protection cosmeceuticals. Conducting further research to isolate and identify the tannins and other compounds responsible for photoprotective properties will be essential for the pharmaceutical and cosmetic industries.Alpha-amylase, Antidiabetic, Photoprotection, Tannin