Evaluation of Geranium spp., Helleborus spp. and Hyssopus spp. polyphenolic extracts inhibitory activity against urease and α-chymotrypsin

Figures & data

Figure 1. FT-IR spectra of: G. robertianum polyphenolic extract (1), H. purpurascens polyphenolic extract (2) and H. officinale polyphenolic extract (3).

Table 1. Contents of total phenolics, total flavonoids and tannins in Geranium spp., Helleborus spp. and Hyssopus spp. polyphenolic extracts.

Sample	Total phenolic (mg GAE/L)	Total flavonoid (mg QE/L)	Tannin content (μg TA/mL)
Geranium robertianum extract	795.6 ± 8.2	168.1 ± 4.3	283.1 ± 5.4
Helleborus purpurascens extract	463.1 ± 8.4	29.3 ± 4.9	369.4 ± 7.1
Hyssopus officinale extract	859.4 ± 9.8	49.8 ± 4.2	311.2 ± 6.3

Results are mean ± SD of three parallel measurements.

Table 2. Retention time, regression equations, correlation coefficients, linear ranges and LD for phenolic compounds from Geraniumv spp., Helleborus spp. and Hyssopus spp. extracts.

No	Compound	m/z	tR (min)	Regression equation	R^2	Linear range (ppm)	LD (ppm)
1	Ellagic acid	322	25	y = 129 506 x − 141 208	0.9778	0.2–20	1.12
2	Rutin	309	23.7	y = 552 196 x − 106 554	0.9968	0.2–20	0.19
3	Luteolin	253	34.7	y = 2 E+06 x + 64 075	0.9937	0.1–10	0.01
4	Quercetin	348	32.5	y = 494 543 x + 212 053	0.9929	0.2–20	0.01
5	Kaempferol	370	40	y = 1 E+06 x + 261 538	0.993	0.2–20	0.02
6	Gallic acid	366	3.3	y = 145 642 x + 81 513	0.9799	0.2–20	0.02
7	Caffeic acid	16	179	y = 229 939 x − 95 498	0.9994	1–20	0.42
8	Ferulic acid	23.9	193	y = 22 695 x + 15 539	1	1–20	0.07

t_R, retention time; LD, limit of detection.

Table 3. Phenolic acids and flavonoid contents in G. robertianum, H. purpurascens and H. officinale polyphenolic extracts.

	Content (mg/kg)
Sample	Ellagic acid	Caffeic acid	Ferulic acid	Coumaric acid	Gallic acid	Rutin	Luteolin	Kaempferol
Geranium robertianum extract	900.13	0	0	0	1070.78	23.83	4.03	1.96
Helleborus purpurascens extract	54.88	82.96	70.72	0	57.47	38.47	2.64	0
Hyssopus officinale extract	0	788.12	1238.68	53.09	12.15	6.59	5.90	0

Figure 2. Urease inhibition activity of Geranium spp., Helleborus spp. and Hyssopus spp. polyphenolic extracts (concentration of each herbal extract: 1.5 mg/mL).

Figure 3. α-Chymotrypsin inhibition activity of Geranium spp., Helleborus spp. and Hyssopus spp. polyphenolic extracts (concentration of each herbal extract: 1.5 mg/mL).

Figure 4.  The effect of polyphenolic extracts on kinetic plots of urease (A) and α-chymotrypsin (B).

Figure 5.  Lineweaver–Burk plots of: (A) urease and (B) a-chymotrypsin inhibition by polyphenolic extracts in the absence (♦) or presence of H. purpurascens (▴), G. robertianum (▪) and H. officinale (×).

Figure 6.  Inhibition of urease (A) and a-chymotrypsin (B) activities by polyphenolic extracts (concentration of each herbal extract: 1.5 mg/mL).