Alleged Passionflower Adulteration
The Botanical Adulterants Program (BAP) was notified by Laboratoires Arkopharma,
SA (Carros, France) about the appearance of several batches of adulterated
passionflower (Passiflora incarnata,
Passifloraceae) herb extracts. The adulteration was detected using a high-performance
thin-layer chromatography (HPTLC) method by the in-house analytical development
unit. A comparison with authentic standards showed that the chemical
fingerprint of the adulterant (Figure 1), which contains large amounts of
rutin, is very different from authentic passionflower herb extracts.
Apparently, the fingerprint of the adulterant is very similar to extracts of
Japanese sophora (Styphnolobium japonicum, syn. Sophora japonica, Fabaceae) (Fanny Perraudin, research
scientist at Arkopharma, oral communication, June 8, 2015).
Figure 1: HPTLC assay to detect adulteration of
passionflower extracts. Lanes 1 and 10 (last): standard compounds (rutin,
hyperoside, vitexin, from bottom to top); lane 2: extract made from botanically
authenticated passionflower herb; lanes 3-9: various hydroethanolic
passionflower herb extracts, with EC007861 (Lane 4), EC007867 (Lane 6), and
EC008212 (Lane 7) showing a non-conforming fingerprint and the presence of an
adulterant. Image courtesy of Laboratoires Arkopharma, SA.Another case of passionflower extract adulteration was documented by PhytoLab
GmbH & Co. KG (Vestenbergsgreuth, Germany).
According to their test results, the extract was spiked with rutin. The company
is currently gathering samples from the US and German markets and will perform
a more thorough investigation of the issue.
Comment: The occurrence of passionflower herb adulteration is
rare to our knowledge. The current problem may be due to a supply shortage
(Fanny Perraudin e-mail communication, July 17, 2015) that is exploited by
unscrupulous manufacturers who resort to spiking with pure flavonoids or
flavonoid-rich extracts. Adulteration with rutin, or extracts of Japanese
sophora, is readily detected by chromatographic means but may go unnoticed when
relying only on the total flavonoid content assay using UV/Vis
spectrophotometry, e.g., the method detailed in the Passiflorae herba
or Passiflorae herbae extractum siccum monographs
of the current European Pharmacopoeia.1,2
According to Fanny Perraudin, a revision of the European
Pharmacopoeia monograph is under way. The new monograph3
aims to replace the spectrometric UV/Vis assay for total flavonoids by an HPLC
method measuring isovitexin (e-mail communication, August 18, 2015).
References
1. The European Directorate for the Quality of Medicines & HealthCare. European Pharmacopoeia (EP 8.4). Passiflorae
herbae extractum siccum. Strasbourg, France: Council of Europe;
2014.2. The European Directorate for the Quality of Medicines & HealthCare. European Pharmacopoeia (EP 8.4). Passiflorae
herba. Strasbourg, France: Council of Europe; 2014.3.
The
European Directorate for the Quality of Medicines & HealthCare. Pharmeuropa 27.01. Passiflorae herbae
extractum siccum. Strasbourg, France: Council of Europe; 2015.Note: The evidence for the above-reported case of
adulteration is based on unpublished internal data gathered by the respective companies
but has not been independently verified by a third-party analytical laboratory.
