Extracts of Ginkgo biloba are highly complex mixtures of a multitude of substances. Although medicinal products
based on Ginkgo biloba extracts comply with quality standards defined by regional pharmacopoeias, it is
common ground that the currently known and quantified active ingredients flavonol
glycosides and terpene trilactones are not exclusively relevant for therapeutic efficacy
of the quantified extract. For a comprehensive assessment of the therapeutic efficacy,
the involvement of other compounds also need to be considered. In the present study,
multiple batches of finished Ginkgo biloba products from international markets including
products containing EGb 761® were analyzed by NMR spectroscopy using an untargeted approach to collect quality
data beyond the standard parameters defined by pharmacopoeias. NMR data were statistically
evaluated by principal
component analysis using the software Bruker AMIX v.3.9.15 to assess batch to batch
consistency and compare product composition from different manufacturers.
The analysis revealed a high batch to batch consistency of products based on EGb 761® and major variations between products based on EGb 761® and products of other manufacturers, respectively.
Since finished Ginkgo biloba products of different manufacturers vary in their composition assessed by NMR spectroscopy,
it is an open question whether therapeutic efficacy data may be fully transferrable
if solely based upon equal contents of flavonol glycosides and terpene trilactones.
