Chemical Constituents and Bioactivities of Plantaginis Herba

Plantago, which is derived from the dried whole plant ofPlantago species (Plantaginaceae), is a herbal medicinedistributed and utilized worldwide for centuries. P.asiatica L. and P. depressa Willd. are the endorsedofficial sources of the herb in China. The former is alsoan official medicinal herb in Japan while P. lanceolataL. is commonly used in Europe. Apart from theseofficial species, many other species such as P. majorL. and P. ovolata L. are used in folk medicines for thetreatment of a variety of diseases such as hematuria,chronic inflammation and constipation. In additionto common primary metabolites, a great number ofbioactive constituents have been isolated from theherb, e.g. phenylethanoid glycosides, flavonoids,iridoids, triterpenoids, phenolic acids and so on. Avariety of useful biological activities such as diuretic,anti-infl ammatory, antioxidative, antiviral, antibacterialand immunomodulatory effects was reported, while veryfew contraindications have been described. This articleaims to review (1) the complexity of this herb; (2) whatcomponents of this herb promote human health and (3)what sorts of scientific evidences are available.