Metabolite Profiling of Methanolic Extract of Gardenia jaminoides by LC-MS/MS and GC-MS and Its Anti-Diabetic, and Anti-Oxidant Activities

Abstract

In this study, the methanolic extract from seeds of Gardenia jasminoides exhibited strong antioxidant and enzyme inhibition activities with less toxicity to NIH3T3 and HepG2 cells at the concentration of 100 µg/mL. The antioxidant activities (DPPH and ABTS), α-amylase, and α-glucosidase inhibition activities were found higher in methanolic extract (MeOH-E) than H₂O extract. Besides, 9.82 ± 0.62 µg and 6.42 ± 0.26 µg of MeOH-E were equivalent to 1 µg ascorbic acid for ABTS and DPPH scavenging, respectively while 9.02 ± 0.25 µg and 6.52 ± 0.15 µg of MeOH-E were equivalent to 1 µg of acarbose for inhibition of α-amylase and α-glucosidase respectively. Moreover, the cell assay revealed that the addition of MeOH-E (12.5 µg/mL) increased about 37% of glucose uptake in insulin resistant (IR) HepG2 as compared to untreated IR HepG2 cells. The LC- MS/MS and GC-MS analysis of MeOH-E revealed a total of 54 compounds including terpenoids, glycosides, fatty acid, phenolic acid derivatives. Among the identified compounds, chlorogenic acid and jasminoside A were found promising for anti-diabetic activity revealed by molecular docking study and these molecules are deserving further purification and molecular analysis.

Keywords: GC-MS; Gardenia jasminoides Ellis; LC-MS/MS; anti-diabetic activity; anti-oxidant.

Figure 1

Cytotoxicity of the methanolic extract (MeOH-E) of G. jasminoides in NIH3T3 cell line (a), AO/EB staining assay (b). ** p < 0.01 significant. Scale bar 100 µm.

Figure 2

Cytotoxicity of the methanolic extract (MeOH-E) of G. jasminoides in insulin-resistant (IR) HepG2 cell line (a), glucose uptake (b), AO/EB staining assay (c), mitochondrial membrane potential (d), measurement of nucleus damage by PI (e), analysis of the reactive oxygen species generation (f). Scale bar 100 µm for C & E, and 50 µm for D & F. * p < 0.05, ** p < 0.01, *** p < 0.001 significant.

Figure 3

Structures of selected compounds identified by LC-MS/MS.

Figure 4

MS/MS spectrum of compounds identified from methanolic extract (MeOH-E) of G. jasminoides by LC-MS/MS analysis. Blue markings and the numbers in blue highlighter indicate the predicted MS/MS fragmentation of the compounds provided by MassFragment, an in silico fragmentation tool that uses a systematic bond disconnection approach to identify possible structures from the parent structure.

Figure 5

Molecular catalytic interaction of the compound identified from the methanolic extract (MeOH-E) of G. jasminoides with α amylase. Jasminoside F (a), chlorogenic acid (b), jasminoside A (c), thymine (d), acarbose derived trisaccharide (e), and acarbose (f) interacting with diabetes-related enzyme of α amylase (5E0F).

Figure 6

Molecular catalytic interaction of the compound identified from the methanolic extract (MeOH-E) of G. jasminoides with α glucosidase (5NN8). Jasminoside F (a), jasminoside B (b), chlorogenic acid (c), jasminoside A (d), acarbose derived trisaccharide (e), and acarbose (f) interacting with diabetes-related enzyme α glucosidase (5NN8).