Hypericum exhibits synergistic action between hyperforin, hypericin, & other constituents including flavonoids and xanthones. Hyperforin is a type of phloroglucinol derivative, which is a type of polyphenol; hypericin is a bianthraquinone (aka naphthodianthrone), which is a type of quinone, which is a type of polyphenol; flavonoids are a type of polyphenol.

• Synergism: "The combined action of constituents is greater than would be expected from a consideration of individual contributions" *
• Polyvalent action: "A way of approaching treatment from several angles concurrently...multiple active constituents" *

*Synergy definitions from Trease & Evans ‘Pharmacognosy,’ 15th Ed. Pp 49-50. See ESCOP article on Synergy: http://www.escop.com/epj2pdfs/Williamson.pdf See: J. Barnes. 1999. A close look at synergy and polyvalent action in medicinal plants. Inpharma 1185:3-4.

• Potentiating synergy: Enhancement of activity
• Stabilization synergy: Protecting unstable constituents
• Modification synergy: attenuation of toxicity

The polyphenolic compounds (flavonols, proanthocyanidins) & the terpenoid compounds (diterpene lactones or ginkgolides) have been demonstrated to work together synergistically.

In a whole plant, multiple antioxidants work together in a process known as 'redox cycling' where they reactivate one another and prevent pro-oxidant activity

• Citrus bioflavonoids (~60 kinds known)
• Carotenoids (~20 known)
• Vitamin C
• Anthrocyanin (in Blood Oranges)

See: Maccarone, E. et. al. 1998. Cyanidin-3-(6"-Malonyl)-glucoside. An Important Anthocyanin of Blood Orange Juice. Ital. J. Food Sci. 10:367.

• Ayurvedic "Trikatu" contains Black Pepper (Piper nigrum); enhances actions of other herbs in traditional formulas
• Piperine is an alkaloid isolated from P. nigrum
• Increased absorption of other constituents when taken concurrently
• Delays catabolism of other constituents

See: Effect of Trikatu (Piperine) on the Pharmacokinetic Profile of Isoniazid in Rabbits, http://www.ijp-online.com/archives/1998/030/04/r0254-0256ra.pdf

• Liquorice used in TCM with processed Aconite (Monkshood) to attenuate toxicity
• Study: In a formula with aconite and ginger, increasing the amount of Liquorice decreased the amount of aconite that could be extracted.

Aconitine is the principle toxic alkaloid in Aconite. Glycyrrhiza lepidota is a relative of G. glabra which grows in the Western United States. See: P. Miaorong and L. Jing, pp 28-30, Proc. 40th Ann. Conf. Beijing Univ. Chinese Med., 1996.

• Antiseptic: Aucubin
• Astringent, drawing: tannins
• Anti-inflammatory: flavonoids, iridoids
• Skin healing: Mucilage, allatoin, tannins, sorbitol

Polyvalent: having multiple modes of action

Plantago major & P. lanceolata contain:

• Iridoids: aucubin [0.3-2.5%], catalpol [0.3-2.1%], asperuloside (iridoids are a subclass of monoterpenes, which are a type of terpenoid) (aucubin degrades with heat or drying; best obtained in fresh plant material)
• Flavonoids (a type of polyphenol)
• Phenolic acids (a type of polyphenol)
• Phenylpropanoid glycosides (a type of polyphenol)
• Heteropolysaccharides containing D-galactose, L-arabinose, & ~ 40% uronic acids Allantoin (a nitrogenous derivative of urea)

References: Chiang, L.C., et. al. 2002. Antiviral activity of Plantago major extracts and related compounds in vitro. Antiviral Research 55:53-62.

Rønsted et. al. 2000. Chemotaxonomy of Plantago. Iridoid glycosides and caffeoyl phenylethanoid glycosides. Phytochemistry 55:337-348.