Untargeted Metabolomics Analysis Using FTIR and UHPLC-Q-Orbitrap HRMS of Two Curculigo Species and Evaluation of Their Antioxidant and α-Glucosidase Inhibitory Activities

Abstract

Curculigo orchioides and C. latifolia have been used as traditional medicines such as antidiabetic and anticancer. This study measured the total phenolics and flavonoid contents as well as analyzed the functional groups and chemical compounds using Fourier-transform infrared (FTIR) spectra and UHPLC-Q-Orbitrap-HRMS profiling for the discrimination of plant parts, geographical origin, and compounds that presumably have a significant contribution as antioxidant and α-glucosidase inhibitors on both plants. The total phenolics and flavonoids contents in Curculigo species varied from 142.09 to 452.47 mg gallic acid equivalent (GAE/g) and from 0.82 to 5.44 mg quercetin equivalent (QE/g), respectively. The lowest IC50 for antioxidant and α-glucosidase inhibitory activities is presented by C. latifolia from a higher altitude region. Principal component analysis (PCA) from FTIR and UHPLC-Q-Orbitrap-HRMS data could discriminate the plant parts and geographical origin. Partial least squares (PLS) analysis has identified several functional groups, such as O–H, C–H, C=O, C–C, C–O, and chemical compounds, unknown-185 and unknown-85, that are most likely to contribute to the antioxidant and α-glucosidase inhibitory activities.

Inhibition of α-glucosidase activity, metals content, and phytochemical profiling of Andrographis paniculata from different geographical origins based on FTIR and UHPLC-Q-Orbitrap HRMS metabolomics

“…paniculata powder was extracted using methanol with a ratio between sample and solvent of about 1:10 for 30 minutes at room temperature. Separation of A. paniculata metabolites was performed according to the procedure described by Rafi et al (2021) using Vanquish Flex UHPLC-Q Exactive Plus Orbitrap-High Resolution Mass Spectrometer with Accucore TM phenyl hexyl (100 x 2.1 mm, 2.6 µm) as separation column. We used mobile phase 0.1% formic acid in water (A) and 0.1% formic acid in acetonitrile (B) with gradient elution as follow: 0.00-1.73 min (30-40%B); 1.73-6.93 min (40-75 %B); 6.93-7.80 min (75-100 %B); 7.80-8.23 (100-30 %B), 8.23-13.00 min (30 %B).…”

“…Of the several metabolites belonging to the terpene lactone class, andrographolide is the main characteristic compound in A. paniculata. Andrographolide with m/z 351 (Rafi et al 2021 . This compound is the most dominant in the diterpene lactone group and has a high abundance, especially in the leaves (Komalasari and Harimurti 2015).…”

“…Apart from phenolic acid and diterpene lactones, A. paniculata also has several flavonoid compounds (Gan et al 2019;Rafi et al 2021). A total of 14 flavonoid compounds were identified in the samples used, such as apigenin, luteolin, methoxy flavone derivatives, and andrographidin A. Quantitatively, the relative content of 32 metabolites from seven regions is shown in Figure 3.…”

“…Quality control of medicinal plants can be carried out using a metabolomics approach to obtain information about the chemical components that can be detected to evaluate their raw materials. There is a possibility that a medicinal plant may work synergistically (van der Kooy et al 2009). Several metabolomic approaches can be used to evaluate the quality of medicinal plants, such as metabolite profiling and fingerprint analysis (Awin et al 2016;Umar et al 2021;Aziz et al 2020).…”

“…There is a possibility that a medicinal plant may work synergistically (van der Kooy et al 2009). Several metabolomic approaches can be used to evaluate the quality of medicinal plants, such as metabolite profiling and fingerprint analysis (Awin et al 2016;Umar et al 2021;Aziz et al 2020). Spectroscopic techniques like FTIR is widely used for fingerprint analysis because easy to use, fast, and cheap (Bunaciu et al 2011).…”