Comparative bioactivity assessment of Garcinia mangostana pericarp and Gymnema sylvestre leaves: antioxidant potential, enzyme inhibition and cytotoxicity
Date
2024-11-01
Authors
Bandara, Y. G. A. D. K.
Kalinga, J.
Siriwardhane, U.
Piyasena, N.
Marikkar, J. M. N.
Adikaram, N. K. B.
Jayasinghe, L.
Journal Title
Journal ISSN
Volume Title
Publisher
Postgraduate Institute of Science (PGIS), University of Peradeniya, Sri Lanka
Abstract
Plants are a rich source of bioactive compounds that can help prevent non-communicable diseases by neutralizing free radicals in the body and acting as enzyme inhibitors. This study evaluated the bioactivity of methanolic extracts from Garcinia mangostana pericarp, and Gymnema sylvestre leaves. Crude extracts were investigated for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and ferric reducing antioxidant power (FRAP) assay. In addition, α-amylase inhibitory assay, brine shrimp lethality assay, and lettuce seed germination assay were performed to assess their potency as pharmaceuticals. The DPPH assay demonstrated higher free radical scavenging activity for G. mangostana with a lower IC₅₀ value of 8.76 ± 0.06 mg/L, and G. sylvestre had a lower activity with an IC₅₀ value of 264.97 ± 3.51 mg/L, compared to ascorbic acid as the positive control (IC₅₀ = 1.90 ± 0.01 mg/L). Garcinia mangostana showed higher antioxidant activity by the FRAP assay with a value of 2290.91 ± 3.67 μmol FeSO₄/g, while G. sylvestre showed a lower antioxidant capacity (393.91 ± 8.15 μmol FeSO₄/g) compared to Trolox as the positive control (12070.12 ± 0.30 μmol FeSO₄/g). Furthermore, G. mangostana showed high amylase inhibitory activity, with an IC₅₀ value of 61.46 ± 2.55 mg/L while G. sylvestre showed comparable activity with an IC₅₀ value of 75.40 ± 2.00 mg/L compared to acarbose as the positive control (IC₅₀ =15.97 ± 0.58 mg/L). A higher brine shrimp lethality was observed for G. mangostana extracts with an LC₅₀ of 38.32 ± 1.53 mg/L, whereas G. sylvestre showed lower lethality with an LC₅₀ of 583.25 ± 23.33 mg/L against K₂Cr₂O₇ as the positive control (34.40 ± 0.30 mg/L). Only G. mangostana showed phytotoxicity by the lettuce seed germination assay with an IC₅₀ of 462.22 ± 4.84 mg/L and 221.41 ± 23.09 mg/L for root and shoot, respectively. These results highlight a higher antioxidant potential and effective enzymatic inhibition of G. mangostana compared to G. sylvestre. However, the higher brine shrimp lethality of G. mangostana necessitates consideration of its dosage and application in pharmaceutical formulations.
Description
Keywords
Amylase inhibition , DPPH assay , FRAP assay , Methanolic extract
Citation
Proceedings of the Postgraduate Institute of Science Research Congress (RESCON) -2024, University of Peradeniya, P 154