Hawthorn

Botanical Profile

Note on species delimitation: Depending on the literature, trade context and monograph, the designation hawthorn encompasses several Crataegus species and hybrids.

Hawthorn refers to several species of the genus Crataegus within the Rosaceae. In Europe, Crataegus monogyna and Crataegus laevigata are particularly important; leaves with flowers and fruits are used primarily.

Crataegus species are thorny shrubs or small trees with alternate, usually lobed leaves, white to pinkish flowers in corymbs and small, apple-like red fruits. The genus is taxonomically complex because hybridisation, apomixis and regional forms result in numerous taxa that are difficult to distinguish. In Europe, Crataegus monogyna, Crataegus laevigata and related species are of primary importance. The flowers appear in spring and have a characteristic, slightly heavy odour; the fruits ripen from late summer into autumn. From a raw-material perspective, flowering shoot tips, leaves with flowers, flowers, fruits and the extracts obtained from them are distinguished. Precise information on species and plant part is important for quality and comparability.

Phytochemistry

Hawthorn leaves and flowers contain flavonoids such as hyperoside, vitexin and vitexin-rhamnoside derivatives, as well as oligomeric procyanidins, phenolic acids, triterpenic acids, trace amounts of amines and other polyphenolic accompanying constituents. The fruits have a different profile, with procyanidins, flavonoids, organic acids, pectins, sugars and red pigments. Species, plant part, developmental stage, harvest time, drying and extraction solvent have a marked influence on composition. For extracts, procyanidin and flavonoid contents, drug-extract ratio, solvent and standardisation are important parameters. Fruit preparations must be assessed differently, both sensorially and chemically, from flowering shoot tips or leaves with flowers.

Traditional Uses

Hawthorn is deeply rooted in European hedge, garden and herbal culture. The thorny shrubs served as living fences, habitat for birds and insects, and as a defining element of field margins and cultural landscapes. Flowers, leaves and fruits were described in European herbal tradition and folklore. Regionally, the fruits were processed into purées, jellies or alcoholic preparations, while flowering shoot tips had their own role in herbal preparations. Historical information on hawthorn relates to specific plant parts and must not be transferred to modern extracts without differentiation.

Current Research

Crataegus is among the well-studied European medicinal-plant genera. Research addresses flavonoids, oligomeric procyanidins, extract standardisation, the quality of leaves with flowers, fruit chemistry and pharmacological models. European monographs and assessment reports refer to defined hawthorn species and plant parts. Clinical and preclinical studies are often extract-specific; species, plant part, extraction solvent and standardisation are therefore crucial for interpretation. The genus is also studied taxonomically and ecologically because hybridisation and regional taxa can complicate raw-material identity.

Sources

• Plants of the World Online: Crataegus L.; Royal Botanic Gardens, Kew.
• EMA/HMPC documents on Crataegus spp., folium cum flore.
• Pharmacognostic and specialist literature on hawthorn flavonoids and oligomeric procyanidins.