Investigation of Arsenic-Stressed Yeast (Saccharomyces cerevisiae) as a Bioassay in Homeopathic Basic Research

Abstract

This study investigated the response of arsenic-stressed yeast (Saccharomyces cerevisiae) towards homeopathically potentized Arsenicum album, a duckweed nosode, and gibberellic acid. The three test substances were applied in five potency levels (17x, 18x, 24x, 28x, 30x) and compared to controls (unsuccussed and succussed water) with respect to influencing specific growth parameters. Five independent experiments were evaluated for each test substance. Additionally, five water control experiments were analyzed to investigate the stability of the experimental setup (systematic negative control experiments). All experiments were randomized and blinded. Yeast grew in microplates over a period of 38 h in either potentized substances or water controls with 250 mg/l arsenic(V) added over the entire cultivation period. Yeast's growth kinetics (slope, Et50, and yield) were measured photometrically. The test system exhibited a low coefficient of variation (slope 1.2%, Et50 0.3%, yield 2.7%). Succussed water did not induce any significant differences compared to unsuccussed water. Data from the control and treatment groups were both pooled to increase statistical power. In this study with yeast, no significant effects were found for any outcome parameter or any homeopathic treatment. Since in parallel experiments arsenic-stressed duckweed showed highly significant effects after application of potentized Arsenicum album and duckweed nosode preparations from the same batch as used in the present study, some specific properties of this experimental setup with yeast must be responsible for the lacking response.

Biological Actions, Electrical Conductance and Silicon-Containing Microparticles of Arsenicum Album Prepared in Plastic and Glass Vials

“…34 A direct action of medicines on yeast is unlikely in the present case because, according to the literature, treatment with Ars in decimal dilutions 8x and 16x did not induce any change in S. cerevisiae growth. 35 The decrease in IL-6 production might be considered as the main specific biological effect of Arsenicum album 200cH, since it was observed not only in this potency but in all situations: Ars 200cHG, Ars 200cHGC, and Ars 200cHP. Therefore, these specific effects were not related to the identification of silicon-containing microparticles and agree with the effects of Ars 200cH on leukocytes previously described.…”

Comparative study of two bioassays with weakened duckweed and yeast treated with homeopathic preparations

“…Aims: This investigation examined the hypothesis that more complex organisms show stronger reactions to homeopathic remedies than less complex ones. We compared two Arsenic (As 5+ ) stressed bioassays with duckweed (Lemna gibba, a multi-cellular autotrophic organism) and yeast (Saccharomyces cerevisiae, a singlecellular heterotrophic organism) regarding their response to homeopathic preparations [1].…”

“…The systematic negative control experiments did not yield any significant effects. Application of potentized Arsenicum album in the duckweed bioassay yielded the largest effects compared to water controls without remedies for the parameters leaf area and leaf number (p<0.001) [1,3]. Potentized nosode preparations also had significant effects on duckweed's leaf area and leaf number (p<0.01).…”

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Background:In homeopathic basic research, the question as to the most adequate test systems and apt methodology is still open.Aims: This investigation examined the hypothesis that more complex organisms show stronger reactions to homeopathic remedies than less complex ones. We compared two Arsenic (As 5+ ) stressed bioassays with duckweed (Lemna gibba, a multi-cellular autotrophic organism) and yeast (Saccharomyces cerevisiae, a singlecellular heterotrophic organism) regarding their response to homeopathic preparations [1].

Methods:For duckweed, growth rates of leaf area and leaf number were evaluated. For yeast, growth kinetics were determined by measuring slope, yield and Et50 (point in time when yield was half maximum) of the sigmoid growth curve.

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Progress in the Placebo Debate for Homeopathy?

“…The question of whether or not ultrahigh dilutions can have a physical effect is not resolved scientifically and still remains. It is currently being studied in a number of different ways, [9][10][11][12][13][14] which shows that many scientists and medical researchers believe the phenomena worthy of investigation, and there is extensive ongoing debate and disagreement about the possibility of ultra high dilutions having an effect. The question has clearly not yet been resolved.…”