Abstract
BACKGROUND: Shirakiopsis indica (Willd)., commonly known as Sa-Mor-Ta-Lay in Thailand, is a mangrove plant belonging to the Euphorbiaceae family. As mangrove plants' medicinal potentials are less explored, this study sought to qualitatively and quantitatively verify the bioactive components of Shirakiopsis indica fruits methanolic extract (SIF-ME) at the side of its analgesic, anti-inflammatory and anti-oxidant effects followed by in-silico studies. METHODS: The in-vivo assessments of analgesic activity involved the hot plate test, acetic acid-induced writhing test, and formalin-induced licking test. The anti-inflammatory efficacy was assessed through the human RBC membrane stabilization assay (HRBC), protein denaturation assay, and xylene-induced ear edema methods. Antioxidant potential was implemented by the DPPH scavenging method. RESULTS: The SIF-ME consistently displayed significant anti-nociceptive activity in a dose-dependent pattern (p < 0.05). The maximum analgesic activity was found in the highest dose (200 mg/kg; p < 0.001) in a hot plate, acetic acid-induced writhing test 43.47%, and in formalin-induced licking test in both early phase (43.3%; p < 0.01) and late phase (61.84%; p < 0.001%). The extract provided optimal protection against hemolysis (83.41% decrease) at 1000 µg/mL and significantly inhibited protein denaturation (67.34-26.05%) at doses of 1000-62.5 µg/mL. At 200 mg/kg, the extract showed dose-dependent and substantial inhibition (54.07%; p < 0.01) of xylene-induced ear edema. The in-vitro DPPH (IC(50) = 469.5 µg/mL) results showed remarkable scavenging activity and concentration-dependent reducing power. The extract demonstrates no acute oral toxicity, as indicated by an LD(50) value exceeding 1000 mg/kg body weight. Gas Chromatography-Mass Spectrometry/Mass Spectrometry (GC-MS/MS) analysis was performed which yielded sixty bioactive compounds. In-silico and molecular docking studies revealed favorable pharmacological properties, including good binding affinities and ADME/T profiles. CONCLUSION: These results support the medicinal use of the plant, which makes it a potential source of analgesic, anti-inflammatory, and antioxidant candidates.