Plant Tissue culture and Ultra High Diluted studies: suggesting a novel model using in vitro techniques
INTRODUCTION
Plant tissue culture may be defined as the aseptic culture of cells, tissues, organs or whole plants
under controlled nutritional and environmental conditions (Pierik, 1987; Torres et al., 1998)
The first reports regarding plant tissue culture date back to 1902 when Gotlieb Harberlandt
developed for the first time experiments to maintain mesophyll cells in culture. Since then, in
vitro techniques have been used in a wide range of applications providing information of great
value about problems related to basic and applied aspects of plant science, evaluating the effects
of many different substances and/ or conditions in plant growth and development as well as
contributing to understanding of factors responsible for growth, metabolism, synthesis of
secondary compounds and stress response, for instance.
In vitro culture requires some essential conditions: all plant tissue culture techniques are
undergone under axenic and controlled conditions (culture medium composition, light and
temperature, for instance). Once more, genetically identical plants commonly used in many
studies can be used in order to avoid intraspecific variations.
Many researches on Ultra High Dilutions have been suggesting that standardized laboratory
conditions and homogeneous quality of plants may decrease variables that could, in some way,
distress that experiments (Majewsky et al.,2009, Jäger et al., 2015).
In vitro culture attempt to these statements providing both controlled conditions and
homogeneous cultures by using clonal plants. Considering that, plant tissue culture seems to be
a value model for Ultra High Diluted (UHD) but, since now, none studies involving these
techniques and UDH research seems to be undergone, once no scientific paper were find.
In order to evaluate a possible use of plant tissue culture to study UHD responses it was chosen
Lippia alba (Mill.) N.E.Br. ex Britton & P.Wilson. This specie is a small shrub native of South
America that belongs to Verbenaceae family. This plant produces essential oils with analgesic,
anti-inflammatory, anticonvulsant, antifungal, and myorelaxant properties (Aguiar et al. 2008;
Carmona et al. 2013; Oliveira et al. 2014).
Lippia alba tissue cultures and in vitro essential oil production have already been described in
scientific literature (Gupta et al., 2001; Tavares et al., 2004; JibinaBai et al., 2014). Other Lippia
species were still investigated providing many comparable results about the effect of plant
growth regulator on in vitro development and essential oil profile (Julianni et al., 1999; Peixoto
et al, 2006).