**3. Results**

#### *3.1. The Total Phenolic Contents (TPCs) and Total Flavonoid Contents (TFCs)*

The total phenolic contents (TPCs) and total flavonoid contents (TFCs) of stems, leaves, roots, and whole plant extracts of *G. littoralis* extracts were calculated from the linear regression equation of the gallic acid standard calibration curve. The TPC of different plant parts ranged from 4.27 ± 0.03 to 23.29 ± 0.43 mgGAE/g dry sample. As Figure 1 shows, the leaf and stem (GLSE) and root (GLRE) extracts had the highest and lowest TPCs, respectively. The total flavonoid contents (TFCs) of stems, leaves, roots, and whole plant extracts of *G. littoralis* extracts were determined using colorimetric analysis. The flavonoid content of different *G. littoralis* extract parts ranged from 0.28 ± 0.04 to 4.93 ± 0.30 mgQE/g dry sample. The results showed that fruit (GLFE) extracts contained a higher TFC, followed by GLFE, whole plant (GLAE), and GLRE extracts.

#### *3.2. LC/UVD Quantitative Analysis of Coumarin-Based Compounds*

LC/UVD quantitative analysis of four coumarin components varied widely with the leaf, stem, fruit, whole plant, and root extracts of *G. littoralis* (Table 2). Among the different tested samples, GLSE extracts had the highest scopoletin (53.0 mg/g), and umbelliferone (1.6 mg/g). The lowest amount of scopoletin was observed in GLRE (8.5 mg/g), and of umbelliferone, in GLFE (0.8 mg/g). The significantly (*p* < 0.05) highest amount of imperatorin (31.9 mg/g) and phellopterin (2.3 mg/g) were observed in GLFE and GLAE extracts, respectively (Table 2). It was confirmed that the total content of four types of coumarin was higher in the order of GLSE, GLRE, GLAE, and GLFE (Figure 2).

**Table 2.** LC/UVD quantitative analysis compounds of extracts from *G. littoralis* (Unit: mg/g, dry weight).


<sup>1</sup> GLSE: *G. littoralis* leaf, stem extracts, GLFE: *G. littoralis* fruit extracts, GLAE: *G. littoralis* plant extracts, GLRE: *G. littoralis* root extracts. <sup>2</sup> N.D.: not detected. Each value is means ± SD of three replicate tests. The mean values followed by the same letter are not significantly different based on the DMRT (*p* < 0.05).

**Figure 2.** Representative chromatograms of compounds of extracts from *G. littoralis*.
