Table 4.

Biological activities of compounds isolated from the parasitic plants.

Plant	Parts of Plant Used	Type of Extract(s)	Observation(s)	Bioactive Compounds	Reference(s)
Antibacterial Activity
Scurrula atropurpurea	Leaves Stems	Ethanol extract	Antibacterial in inhibiting the growth of Enterobacter sakazakii	Flavonoids—inhibition bacterial cell wall Triterpenoid—inhibition protein synthesis Tannin	[81]
Scurrula ferruginea	Leaves Stems Flowers	Aqueous extract	Antibacterial activity against (MIC) Staphylococcus aureus Bacillus subtilis Escherichia coli Pseudomonas putida	Phenolic compounds	[82]
Macrosolon cochichinensis	Leaves Stems Junction to its hosts (Haustorium)	Methanolic extract and aqueous extract	Antibacterial activity (with inhibition zones from 4 mm to 8 mm) against Bacillus subtilis Klebsiella pneumonia Vibrio cholera	-	[83]
Scurrula atropurpurea	Leaves Stems Junction to its hosts (Haustorium)	Methanolic extract	Antibacterial activity against Bacillus subtilis (with inhibition zone of 5–6 mm) Escherichia coli (with inhibition zone of 4–5.5 mm) Klebsiella pneumonia (with inhibition zone of 6–7.5 mm) Vibrio cholera (with inhibition zone of 7–8 mm)	-	[83]
Viscum album	Leaves Stems Junction to its hosts (Haustorium)	Methanolic extract	Antibacterial activity against Klebsiella pneumonia with inhibition one of 3–3.5 mm	-	[83]
		Aqueous extract	Antibacterial activity against Bacillus substilis with inhibition one of 2–3 mm.	-
Loranthus micranthus	Leaves	Crude methanol extract followed by fractionation with ethyl acetate and acetone	Antibacterial activity against Staphylococus aureus Bacillus subtilis Pseudomonas aeruginosa Escherichia coli	Alkaloids Flavonoids Terpenoids Tannins	[84]
Anticancer or cytotoxic
Scurrula ferruginea	leaves stems twigs flowers	Extracted with petroleum Ether followed by isolation from ethyl acetate fraction	Quercetin was found to be the most active in the following four human cancer lines: U251 (NCI strain) K562 (CCL-243, ATCC) DU145 (HTB-81, ATCC) MCF-7 (HTB-22, ATCC)	Quercetin Quercitrin 4-O-acetylquercitrin	[41]
Loranthus micranthus	Leaves	Aqueous extract	Genotoxic effects against Allium cepa root cells	Alkaloids Flavonoids Tannins Phenolics Steroids Saponins Cardiacglycosides Reducing sugars	[85]
Loranthus parasiticus	-	The methanol extract, ethyl acetate and aqueous fractions	Cytotoxic against the ovarian cancer cell lines, namely SKOV3, CAOV3 and OVCAR-3	Proanthocyanidins of AC trimer Proanthocyanidins of (+)-catechin Coriamyrtin Tutin Corianin Coriatin	[45]
Scurrula oortiana	Leaves Stems	Aqueous and methanolic extracts	WEHI-164 cells sensitive to TNFα when treated with extract	-	[31]
Scurrula atropurpurea	Leaves Stems	Extracted with 70% acetone followed by fractionation with ethyl acetate	Octadeca-8,10,12-triynoic acid was most potent against mesothelial cells isolated from Donryu rats	Octadeca-8,10-diynoic acid Z-octadec-12-ene-8,10-diynoic acid Octadeca-12-ene-8,10-triynoic acid Epigallocatechin-3-O-gallate	[47]
Scurrula atropurpurea	-	Preparation of C16-Alkynic fatty acid	inhibitory effects on cancer cell invasion assay mesothelium monolayer by using MM1 cell line isolated from rat ascites hepatoma AH130 cells	Hexadeca-6,8,10-triynoic acid Hexadeca-8,10,12-triynoic acid	[46]
Anti-hypertensive
Scurrula ferruginea Scurrula ferruginea	Whole aerial plant	Crude methanol extract, chloroform extract, ethyl acetate extract	In vivo experiment: Vasorelaxant by using Rat thoracic aorta	Polyphenolic and Flavonoids compounds	[35]
		Methanolic Extract	Guinea Pig Ileum: Hypotensive and Spasmogenic effects	Polyphenolic and Flavonoids compounds	[86]
		Methanolic extract and by n-butanol fraction	Rat thoracic aorta rings: vascular smooth muscle relaxation in vitro and a dose-dependent hypotensive action in vivo.	Terpenoids	[87]
		Methanolic extract	The vascular effects of three different concentrations of this extract by reversible noncompetitive antagonism of norepinephrine-induced vasoconstriction	Terpenoids	[88]
		Methanolic extract and then successively fractionated using chloroform, ethyl acetate and n-butanol	The n-butanol fraction of LFME (NBF-LFME) was studied using isolated rat thoracic aorta: relaxation by stimulating muscarinic receptors, activating the endothelium-derived nitric oxide-cGMP-relaxant pathway	Terpenoids	[36]
Antioxidant
Loranthus parasiticus	Leaves Branches	Water/aqueous extract followed by methanolic extract, then ethyl acetate extract.	Antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity	Sesquiterpene lactones: Coriamyrtin Tutin Corianin Coriatin Proanthocyanidins AC trimer and (+)-catechin	[45]
Scurrula ferruginea	Stem (highest anti-oxidant activity) Leaves Flowers (lowest anti-oxidant activity)	Acetone extract (mostly stem)	Antioxidant capacity of extracts were evaluated using DPPH free radical scavenging assay	Phenolic compounds	[82]
Loranthus regularis Steud. ex Sprague	Leaves Flowers Twigs	Ethyl acetate fraction of a methanol extract	The antioxidant power of the extract, its fractions and isolated compounds was studied using DPPH scavenging and b-carotene/linoleic acid tests	Quercetin 3-O-β-l-galactopyranoside Quercetin 3-O-β-l-arabinopyranoside Quercetin 3-O-α-l-rhamnopyranoside	[89]
Scurrula parasitica	Leaves (mature and tender)	Methanolic extract of the matured leaves	DPPH free radical scavenging assay	Phenolic compounds	[90]
Loranthus parasiticus	Leaves	Ethanolic extract and further partitioned into ethyl acetate fraction and followed by aqueous fraction	Measurement of intracellular reactive oxygen species (ROS); H2O2-induced oxidative damage in NG108-15 cells	Proanthocyanidins AC trimer and (+)-catechin	[91,92]
Viscum album	Leaves Stem	Aqueous extract Ethanolic extract Acetone extract Methanolic extract (leaves rich in phenolics and carotenoids)	DPPH free radical scavenging assay ORAC method TEAC method Folin-Ciocalteu FRAP method DCFH-DA assay (to measure intracellular ROS levels)	Phenolic acids	[24,93,94]
Antiviral
Scurrula ferruginea	Leaves Stems Flowers	Methanolic extracts	Antiviral activity against poliovirusactive on Poliovirus and activity on the U251 glioblastoma cells	Flavonoids Condensed Tannins	[52]
Loranthus parasiticus	Leaves	Methanolic extracts	Anti HIV-1 effect	-	[95]
Scurrula oortiana	Leaves Stems	Aqueous extracts	Anti Marek’s Disease Virus (MDV)	-	[32]
Neuroprotection
Loranthus parasiticus	Leaves	Aqueous fraction	Neuroprotective role in NG108-15 cells	Proanthocyanidins of AC trimer	[91]
		Aqueous fraction	Increased cell viability and decreased intracellular ROS level in a dose-dependent manner against H2O2-induced oxidative stress in NG108-15 cells	Proanthocyanidins of (+)-catechin
Anti-schizophrenic Activity
Loranthus parasiticus	Leaves	Ethanol extract	Coriamyrtin with strong catatonic action in mice were effective components of L. parasiticus for shock therapy in catatonia treatment.	Coriamyrtin	[45]
			Non-toxic corianin with comparable activity to electric shock or insulin has been used for catatonia treatment by muscle injection in hospitals of various areas of China.	Corianin (non-toxic)
			Tutin with strong catatonic action in mice were effective components of L. parasiticus for shock therapy in catatonia treatment.	Tutin
Miscellaneous studies
Scurrula ferruginea	Whole aerial plant	Methanolic Extract	Spasmogenic effect in isolated guinea pig ileum	Flavonoids Terpenoids Saponin Tannins	[86]
		S. ferruginea methanol extract and followed by ethyl acetate and n-butanol fraction	In vitro Cholinomimetic Effect		[96]
Taxillus chinensis	Stem	Extracted with 50% ethanol in the ratio 1:20 (w/v)	Potent inhibition on fatty acid synthase (FAS) that is proposed to be a potential therapeutic target for treatment of obesity.	-	[78]

Cell lines: 3LL—Lewis lung carcinoma cells, DU145—human prostate cancer cell line, K562—human leukemic cell line, L1210—mouse lymphocytic leukemia cells, MCF-7—human breast adenocarcinoma cell line, NG108-15 cells—neuroblastoma-glioma hybrid cells, U251—Human glioblastoma astrocytoma cell line.