Diplazium esculentum (Retz.) Sw.: Ethnomedicinal, Phytochemical, and Pharmacological Overview of the Himalayan Ferns

Table 4

Previous antioxidant studies in Diplazium esculentum.

Plant part used and solvent system	Name of assay	Key results			References
		Plant extracts	Positive control	Antioxidant activity
Whole plant, (chloroform, n-butanol, aqueous)	Free radical scavenging (DPPH)	-404 μg/mL	μg/mL	Moderate	[77]
	Radical cation scavenging activity (ABTS^+)	-273 μg/mL	μg/mL	Moderate
	Ferric reducing antioxidant power (FRAP)	0.44-0.55 mg/g	—
Leaves (methanol)	Free radical scavenging (DPPH)	31.35-57.95% inhibition	91.99-97.03% inhibition	Moderate	[57]
Leaves (methanol)	Free radical scavenging (DPPH)	μg/mL	μg/mL	Weak	[83]
Leaves (protein)	Free radical scavenging (DPPH)	mg/mL	—	—	[84]
	Free radical scavenging (DMPD·+)	mg/mL	—	—
	Radical cation scavenging activity (ABTS^+)	mg/mL	—	—
Leaves (not reported)	Free radical scavenging (DPPH)	336-3359 ORAC unit^2/g	—	—	[50]
Leaves (ethanol, vinegar, acetic acid, aqueous)	Free radical scavenging activity (DPPH)	258-303 μmol TE/100 g	—	—	[85]
Leaves (chloroform, methanol)	Total antioxidant capacities (TAC)	181.94-207.41 mg/g	—	—	[46]
	Free radical scavenging (DPPH)	-95669 μg/mL	μg/mL	Weak
Leaves (methanol)	Free radical scavenging activity (DPPH)	mg/mL	—	—	[86]
	Metal chelating activity	52.07 mg/mL	—	—
	Ferric reducing antioxidant power (FRAP)	2.12 μg/mg	—	—
	Radical cation scavenging activity (ABTS^+)	mg/mL	—	—
Fronds (aqueous, ethanol)	Radical cation scavenging activity (ABTS^+)	09.60-57.84% inhibition	—	—	[65]
	Hydrogen peroxide scavenging (H2O2)	15-40% inhibition	50% inhibition	Strong
Leaves (methanol)	Hydroxyl radical scavenging (OH·)	μg/mL	μg/mL	Weak	[87]
	Superoxide anion scavenging (O2·^−)	μg/mL	μg/mL	Strong
	Nitric oxide radical scavenging (NO)	μg/mL	μg/mL	Moderate
	Hydrogen peroxide scavenging (H2O2)	mg/mL	μg/mL	Strong
	Peroxynitrite scavenging (ONOO^−)	mg/mL	μg/mL	Strong
	Singlet oxygen scavenging (^1O2)	μg/mL	μg/mL	Moderate
	Hypochlorous acid scavenging (HOCl)	μg/mL	μg/mL	Moderate
	Iron chelating	mg/mL	μg/mL	Strong
	Lipid peroxidation inhibition	μg/mL	μg/mL	Moderate
Leaves (petroleum ether, chloroform, acetone, methanol, aqueous)	Ferric reducing antioxidant power (FRAP)	0.22-7.6 mM/dry weight	—	—	[88]
Leaves (aqueous-methanol, acetone)	Free radical scavenging (DPPH)	-3.60 mg dry wt.	—	—	[89]
	Ferric reducing antioxidant power (FRAP)	4.99-8.78 mg/g	—	—
Leaves (methanol)	Free radical scavenging (DPPH)	μg/mg	μg/mg	Weak	[90]
Leaves (aqueous)	Free radical scavenging (DPPH)	50 μmol/g	—	—	[91]
	Ferric reducing antioxidant power (FRAP)	100 mol/g	—	—
	Cupric ions chelation assay	80% inhibition	—	—

(-): not mentioned in the reference papers; (): antioxidant activity was considered strong (less than 100 μg/mL), moderate (100 to 500 μg/mL), weak (500 to 1000 μg/mL), or inactive (over 1000 μg/mL) compared with control.