Bioactive compounds from Hypericum humifusum and Hypericum perfoliatum: inhibition potential of polyphenols with acetylcholinesterase and key enzymes linked to type-2 diabetes

Figures & data

Table 1. Phenolic content and concentrations of hypericin and hyperforin in H. humifusum and H. perfoliatum extracts.

	Hypericin (mg/g of dry extract)	Hyperforin (mg/g of dry extract)	TPC^b [mg GAE/g]	TF^c [mg RE/g]
Hypericum humifusum	90 ± 1^a	30 ± 0.09^a	113.52 ± 4^a	41.06 ± 0.8^a
Hypericum perfoliatum	60 ± 0.9^b	8.5 ± 0.2^b	48.47 ± 0.2^b	8.45 ± 0.1^b

Different superscript letters (a and b) in the same column indicate significant difference (p  < 0.05).

TPC: total phenolic compounds; TF: total flavonoids.

^a Results are reported as mean ± standard deviation of three replicates (95% confidence).

^b mg gallic acid equivalents/g dry weight.

^c mg quercetin equivalents/g dry weight, d: mg.

Table 2. Radical scavenging, reducing power and metal chelating activities of MeOH extracts.

	H. humifusum	H. perfoliatum
Radical scavenging activity
DPPH^b [μmoles Trolox/g]	84.63 ± 1.62	52.31 ± 1.3
ABTS^b radical cation (mg TEs/g)	180.87 ± 1.8	80.6 ± 1.6
Reducing power
FRAP^b [mmol Fe^2+/g]	80.23 ± 0.07	50 ± 0.07
Metal chelating
Ferrous ion chelating (mg EDTAEs/g)	3.7 ± 0.08	8.76 ± 0.08

^a Results are reported as mean ± standard deviation of three replicates (95% confidence).

^b μM Trolox equivalents (TE).

Table 3. Enzyme inhibitory activity of the MeOH extracts (mean ± SD).

Samples	Acetyl cholinesterase (mg GALAEs/g)	α-Amylase (mmol ACEs/g)	α-Glucosidase (mmol ACEs/g)
Hypericum humifusum	4.57 ± 0.3	2.55 ± 0.08	8 ± 0.08
Hypericum perfoliatum	3.86 ± 0.02	0.73 ± 0.04	3.88 ± 0.07

GALAEs: galanthamine equivalents; ACEs: acarbose equivalents.

Table 4. MIC and MBC results of of H. humifusum and H. perfoliatum extracts against selected bacterial and yeast strains.

	CON+		H. humifusum		H. perfoliatum
Bacterial strain	MIC	MBC	MIC	MBC	MIC	MBC
Escherichia coli G(−)	18.5	25	350	500	350	600
Salmonella typhimurium G(−)	15	24	500	550	500	650
Pseudomonas aeruginosa G(−)	1.6	3.5	300	600	350	650
Pseudomonas aeruginosa G(−)	1	2.5	300	600	350	600
Enterococcus faecium G(+)	10.5	13	250	400	450	500
Staphylococus aureus G(+)	5	10.5	250	400	300	400
Staphylococcus epidermidis G(+)	6.5	12	200	350	350	450
Bacillus subtilis G(+)	15	30	350	350	350	450
Candida albicans	5	11.5	300	350	250	350

CON+: positive control, antibiotic: Ampicillin for all strains except for Pseudomonas aeruginosa where positive control and Gentamicin.

MIC: minimal inhibitory concentration (μg mL⁻¹).

MIC was defined as the lowest concentration of the compounds produced >95% growth reduction compared with the growth in the control well.

MBC: minimum bactericidal concentration (μg mL⁻¹).