Biological Activity Evaluation and In Silico Studies of Polyprenylated Benzophenones from Garcinia celebica

This study aimed to isolate polyprenylated benzophenones from the rootbark of Garcinia celebica and assess their activities in vitro and in silico. The antioxidant activity was evaluated by the DPPH, ABTS, and FRAP methods. The cytotoxicity was evaluated against HeLa, MCF-7, A549, and B16 cancer cell lines. The antiplasmodial activity was performed against the chloroquine-sensitive Plasmodium falciparum strain 3D7. Molecular docking was analyzed on alpha-estrogen receptor (3ERT) and P. falciparum lactate dehydrogenase enzyme (1CET). The prediction of ADMET for the compounds was also studied. For the first time, (-)-cycloxanthochymol, isoxanthochymol, and xanthochymol were isolated from the root bark of Garcinia celebica. The antioxidant and cytotoxicity evaluation showed that all benzophenones exhibited antioxidant activity compared to gallic acid and quercetin as positive controls and also exhibited strong activity against HeLa, MCF-7, A549, and B16 cell lines compared to cisplatin as the positive control. The antiplasmodial evaluation showed that isoxanthochymol exhibited activity against the chloroquine-sensitive P. falciparum strain 3D7. In addition, the in silico molecular docking study supported in vitro activities. The ADMET analysis also indicated the isolated benzophenones are potential oral drug candidates.

Anti-Neuraminidase Bioactives from Manggis Hutan (Garcinia celebica L.) Leaves: Partial Purification and Molecular Characterization

The neuraminidase enzyme (NA) from the influenza virus is responsible for the proliferation and infections of the virus progeny, prompting several efforts to discover and optimize effective neuraminidase inhibitors. The main aim of this study is to discover a new potential neuraminidase inhibitor that comes from Garcinia celebica leaves (GCL). The bioassay-guided isolation method was performed to obtain lead compounds. The binding interaction of the isolated compounds was predicted by using molecular docking studies. Friedeline (GC1, logP > 5.0), two lanastone derivatives (methyl-3α,23-dihydroxy-17,14-friedolanstan-8,14,24-trien-26-oat (GC2) and 24E-3a,9,23-trihydroxy-17,14-friedolanostan-14,24-dien-26-oate (GC3) with LogP > 5.0) and catechin (GC4, LogP = 1.4) were identified. The inhibitory potency of these four compounds on NA from C. perfringens and H₁N₁ was found to be as follows: GC4 > GC2 > GC3 > GC1. All compounds exhibited higher inhibitory activity towards C. perfringens NA compared to H₁N₁ NA. From the molecular docking results, GC4 favorably docked and interacted with Arg118, Arg371, Arg292, Glu276 and Trp178 residues, whilst GC2 interacted with Arg118, Arg371, Arg292, Ile222, Arg224 and Ser246. GC3 interacted with Tyr406 only. GC4 had potent NA inhibition with free energy of binding of −12 kcal/mol. In the enzyme inhibition study, GC4 showed the highest activity with an IC₅₀ of 60.3 µM and 91.0 µM for C. perfringens NA and H₁N₁ NA—respectively.

Catechin Isolated from Garcinia celebica Leaves Inhibit Plasmodium falciparum Growth through the Induction of Oxidative Stress

BACKGROUND

Resistance of antimalarial drugs to Plasmodium falciparum has become a major concern in malaria eradication. Although it is also affected by several socioeconomic factors, a new antiplasmodial agent is needed for a global malaria control program.

OBJECTIVE

In this study, we attempted to uncover the antiplasmodial properties of Garcinia celebica, an Indonesian medicinal plant, along with the responsible compound and its possible mechanism.

MATERIALS AND METHODS

The G. celebica leaves were ethanol extracted and fractionated based on their polarity using n-hexane, ethyl acetate, and water. The antiplasmodial activity was tested in vitro against chloroquine-resistant P. falciparum at 100 μg/ml for 72 h. The active compound of the most active ethyl acetate fraction was subsequently isolated using column chromatography and identified by nuclear magnetic resonance.

RESULTS

The IC₅₀ of (+)-catechin, the characterized compound, against P. falciparum was 198 μM in 24 h and experiment. The isolated catechin inhibited P. falciparum growth in both trophozoite and schizont stages. An additional experiment also suggests that the antiplasmodial property of catechin occurs through the induction of the oxidative stress to P. falciparum.

CONCLUSION

This result shows that the potential of catechin and its antimalarial properties should be explored further.

SUMMARY

Garcinia celebica leaf extract and fractions inhibit Plasmodium falciparum growthCatechin, the active compound of Garcinia celebica leaf extract, inhibits Plasmodium falciparum growth in a time- and dose-dependent manner Abbreviations used: RBC: Red Blood Cells; IC50: Inhibition Concentrattino 50; MeOH: Methanol; RPMI: Roswell Park Memorial Institute; EI: Electron Ionization.

Apoptosis-mediated antiproliferative activity of friedolanostane triterpenoid isolated from the leaves of Garcinia celebica against MCF-7 human breast cancer cell lines

The leaves of Garcinia celebica strongly inhibit the proliferation of MCF-7 human breast adenocarcinoma cell lines. The present study focused on investigating the active anticancer and antiproliferative compound from the G. celebica leaves and assessing its mechanism of action. Ethanol extracts of G. celebica were fractionated based on their polarity using n-hexane, ethyl acetate and water. The antiproliferative properties were tested in vitro against MCF-7 human breast cancer cell lines using the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay. The active compound was subsequently isolated using column chromatography and identified by nuclear magnetic resonance. The characterized compound was also tested for its antiproliferative properties and the mechanism by which it induces apoptosis in MCF-7 cells by western blot analysis of the activated apoptotic proteins. This resulted in the isolation of a friedolanostane triterpenoid, which was determined to be methyl-3α, 23-dihydroxy-17,14-friedolanstan-8,14,24-trien-26-oat. This compound inhibited MCF-7 cell proliferation in a time- and dose-dependent manner with IC50 values of 82 and 70 µM for the 24 and 48 h treatments, respectively. Furthermore, the western blot analysis suggested that the compound exerted its anticancer activities by promoting apoptosis through the inhibition of the oncogenic protein Akt, thereby increasing the expression of poly (ADP-ribose) polymerase (PARP) protein. These results suggest that methyl-3α,23-dihydroxy-17,14-friedolanstan-8,14,24-trien-26-oat is the anticancer compound found in G. celebica, providing a basis for its potential use in cancer disease management.