Comparative study of the antidiabetic potential of Paederia foetida twig extracts and compounds from two different locations in Malaysia

Figures & data

Figure 1. The chemical compounds found in Paederia foetida.

Figure 2. Percentage inhibition of α-amylase by different extracts of Paederia foetida twig from Pahang, Malaysia. The different extracts were compared with acarbose and p < 0.05 (p = 0.0001). *indicates significance at the 0.05 level, **indicates significance at the 0.01 level.

Figure 3. Percentage inhibition of α-amylase by different extracts of Paederia foetida twig from Johor, Malaysia. The different extracts were compared with acarbose and p < 0.05 (p = 0.0101). *indicates significance at the 0.05 level.

Figure 4. Percentage inhibition of α-glucosidase by different extracts of Paederia foetida twig from Pahang, Malaysia. The different extracts were compared with acarbose and p < 0.05 (p = 0.0080).

Figure 5. Percentage inhibition of α-glucosidase by different extracts of Paederia foetida twig from Johor, Malaysia. The different extracts were compared with acarbose and p < 0.05 (p = 0.0019). *indicates significance at the 0.05 level.

Table 1. IC₅₀ values for α-glucosidase and α-amylase inhibition by extracts of Paederia foetida twig.

Samples	α-Glucosidase inhibition activity IC50 (μg/mL)		α-Amylase inhibition activity IC50 (μg/mL)
	Pahang (PFP)	Johor (PFJ)	Pahang (PFP)	Johor (PFJ)
Hexane	2394 ± 0.02^abcd	1207 ± 0.03^abce	11.64 ± 0.02^a	13.80 ± 0.01^b
Chloroform	257.2 ± 0.01	245.6 ± 0.01^abcf	14.83 ± 0.05	9.60 ± 0.01^c
Ethyl acetate	285.1 ± 0.01	1062 ± 0.01	23.33 ± 0.02	62.08 ± 0.00
Methanol	1472 ± 0.06^a	>10 000	>500	>500
Acarbose	0.056 ± 0.01 (0.087 ± 0.01 μM)		10.57 ± 0.01 (16.37 ± 0.01 μM)
Scopoletin	0.011 ± 0.11^defg (0.057 ± 0.11 μM)		0.010 ± 0.13^abcg (0.052 ± 0.13 μM)

All values are expressed as mean ± standard deviation (n = 3). p < 0.05. Data with different superscripts (a, b, c, d, e, f, g) were considered significant.

Figure 6. Percentage inhibition of DPPH scavenging activities by different extracts of Paederia foetida twig from Pahang, Malaysia. The different extracts were compared with α-tocopherol and ascorbic acid, p < 0.05 (p = 0.0021). * indicates significance at the 0.05 level.

Figure 7. Percentage inhibition of DPPH scavenging activities by different extracts of Paederia foetida twig from Johor, Malaysia. The different extracts were compared with α-tocopherol and ascorbic acid, p < 0.05 (p = 0.0001). * indicates significance at the 0.05 level, ** indicates significance at the 0.01 level.

Figure 8. Binding of scopoletin to α-amylase pocket. (a) 2D-diagram of ligand interaction. (b) receptor–ligand interaction. (c) Hydrophobic surface. (d) Hydrogen bond surface.

Figure 9. Binding of scopoletin to α-glucosidase pocket. (a) 2D-diagram of ligand interaction. (b) receptor–ligand interaction. (c) Hydrophobic surface. (d) Hydrogen bond surface.

Table 2. β-Carotene bleaching activity and IC₅₀ values of DPPH by extracts of Paederia foetida twig.

Samples	DPPH IC50 (μg/mL)		β-Carotene bleaching activity, %
	Pahang (PFP)	Johor (PFJ)	Pahang (PFP)	Johor (PFJ)
Hexane	>1000	>1000	88.08 ± 0.02^a	69.41 ± 0.01^e
Chloroform	181.97 ± 0.07^b	27.27 ± 0.01^abdef	92.24 ± 0.02^b	72.89 ± 0.03^abcdef
Ethyl acetate	>1000	35.85 ± 0.05^e	80.07 ± 0.02^c	73.83 ± 0.01^e
Methanol	>1000	>1000	77.14 ± 0.02^d	77.66 ± 0.01^fg
α-Tocopherol	19.09 ± 0.00^abegh (44.32 ± 0.00 μM)		99.35 ± 0.02^abcdegh
Ascorbic acid	15.15 ± 0.01^abegi (86.02 ± 0.01 μM)		n.a.
BHT	9.97 ± 0.00^aegj (45.25 ± 0.00 μM)		95.88 ± 0.01^abcdegj
BHA	10.42 ± 0.01^abegk (57.81 ± 0.01 μM)		98.99 ± 0.00^abcdegk
Scopoletin	655.5 ± 0.00^fhijk (3411.21 ± 0.00 μM)		71.73 ± 0.01^fhijk

All values are expressed as mean ± standard deviation (n = 3). p < 0.01. Data with different superscripts (a, b, c, d, e, f, g, h, i, j, k) were considered significant.

n.a. are not applicable.

Table 3. Binding interaction of the complex ligands.

Complex ligand	Binding energy (kcal/mol)	Number of closest residues	RMSD (Å)
α-Amylase–scopoletin	−6.03	7	3.16
α-Glucosidase–scopoletin	−2.92	5	6.04