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Duckweed as a test system

Posted: 11 Nov 2014, 15:23
by Mark
Development of a Test System for Homeopathic Preparations Using Impaired Duckweed (Lemna gibba L.)

Tim Jäger, MSc, Claudia Scherr, PhD, Meinhard Simon, PhD, Peter Heusser, MD, and Stephan Baumgartner, PhD

Abstract
Objectives: A bioassay with arsenic-stressed duckweed (Lemna gibba L.) was developed to study potentially
regulative effects of homeopathic preparations. We compared potentized substances (nine different potency
levels between 17 x and 33 x ) with two controls (unsuccussed and succussed water) regarding their influence on
number- and area-related growth rate and color of fronds (leaves). Screening included 11 potentized substances:
Arsenicum album, gibberellic acid, nosode, arsenic(V), phosphorus, Conchae, Acidum picrinicum, Argentum
nitricum, Crotalus horridus, Hepar sulfuris, and Mercurius vivus naturalis.

Design: Duckweed was stressed with arsenic(V) for 48 hours. Afterwards, plants grew in either potentized
substances or water controls for 6 days. Growth rate and color of fronds were determined with a computerized
image analysis system for different time intervals (days 0–2, 2–6, 0–6). A systematic negative control experiment
with unsuccussed water was used to investigate the stability of the bioassay. All experiments were randomized
and blinded.

Results: Arsenicum album and nosode potencies increased frond number–related growth rate compared to
controls (succussed water controls or pooled water controls [succussed and unsuccussed], p<0.05, t test).
Regarding color classification, no effects were observed.

Conclusions: The experimental setup with L. gibba stressed by arsenic(V) provides a valuable tool to investigate
regulative effects of potentized substances. In order to verify the effects of Arsenicum album and nosode potencies,
further independent replication experiments are necessary.