Preface
Carotenoids are a large group of isoprenoid metabolites covering more than 600 compounds. A typical carotenoid molecule is a C40 hydrocarbon and forms a chromophore of
double bonds in conjugation which absorbs light in the blue light spectrum, thus appearing
in colors ranging from yellow to orange and red. Although carotenoids are usually synthesized by photosynthetic organisms such as plants, animals including humans need to
consume carotenoids with their diet. Carotenoids present in our food are an essential source
of retinoids such as vitamin A and visual pigments, but they are also used to produce other
biologically active molecules that prevent degenerative diseases and promote health. In
plants, the functions of carotenoids cover almost all aspects in biological systems, including
photosynthesis, protection against oxidative stresses, visual attraction, signaling, aroma
composition, developmental regulation, and membrane stabilization.
Accordingly, research on carotenoids developed rapidly within the last years, supported
by the development of methods suitable to analyze carotenoid cleavage products and also by
numerous approaches succeeding in altering carotenoid amounts and patterns in various
plant tissues and food sources. Associated with the development of these techniques,
knowledge on the functions of carotenoids increased significantly and provided novel
insights on how carotenoid biosynthesis is dynamically regulated in coordination with
their storage and degradation in plant cells as well as the contribution of carotenoid cleavage
products in numerous processes in plants and animals.
This collection of methods is intended to enable carotenoid research into these recently
extended research areas and answer questions which now can be asked. The methods are also
thought to support researchers approaching carotenoid functions from a different research
area, who are thus new in the field or have only little experience. Accordingly, the methods
are described with additional details of practical relevance usually not included in research
publications, which are therefore sometimes difficult to translate into real lab life. We cover a
wide spectrum of research aspects, including established protocols for carotenogenic and
carotenoid-cleavage enzyme characterizations, a large chapter on analytical methods which
meets the need of increasing knowledge on catabolic carotenoid pathways, chapters on how
both anabolic and catabolic pathways can be considered as well as a chapter on imaging
carotenoid storage and carotenogenic metabolon formation in living systems. Finally, we
included practical instructions on how carotenoid metabolism can be altered in model
organisms and how carotenoid function can be assessed in animal systems.
This method collection builds on the willingness of all contributing authors to provide
their detailed lab protocols and make them available to a greater audience which we highly
appreciate. These methods are intended to be used as reference methods to unify research
methods and to allow carotenoid research to be extended into other fields of plant and
animal research. We would like to thank John M. Walker for the invitation to create this
volume of Methods in Molecular Biology and for his careful instructions on the way to
finalize it.
Barcelona, Spain
Manuel Rodrı ´guez-Concepci on
Freiburg, Germany
Ralf Welsch
v
Carotenoids are a large group of isoprenoid metabolites covering more than 600 compounds. A typical carotenoid molecule is a C40 hydrocarbon and forms a chromophore of
double bonds in conjugation which absorbs light in the blue light spectrum, thus appearing
in colors ranging from yellow to orange and red. Although carotenoids are usually synthesized by photosynthetic organisms such as plants, animals including humans need to
consume carotenoids with their diet. Carotenoids present in our food are an essential source
of retinoids such as vitamin A and visual pigments, but they are also used to produce other
biologically active molecules that prevent degenerative diseases and promote health. In
plants, the functions of carotenoids cover almost all aspects in biological systems, including
photosynthesis, protection against oxidative stresses, visual attraction, signaling, aroma
composition, developmental regulation, and membrane stabilization.
Accordingly, research on carotenoids developed rapidly within the last years, supported
by the development of methods suitable to analyze carotenoid cleavage products and also by
numerous approaches succeeding in altering carotenoid amounts and patterns in various
plant tissues and food sources. Associated with the development of these techniques,
knowledge on the functions of carotenoids increased significantly and provided novel
insights on how carotenoid biosynthesis is dynamically regulated in coordination with
their storage and degradation in plant cells as well as the contribution of carotenoid cleavage
products in numerous processes in plants and animals.
This collection of methods is intended to enable carotenoid research into these recently
extended research areas and answer questions which now can be asked. The methods are also
thought to support researchers approaching carotenoid functions from a different research
area, who are thus new in the field or have only little experience. Accordingly, the methods
are described with additional details of practical relevance usually not included in research
publications, which are therefore sometimes difficult to translate into real lab life. We cover a
wide spectrum of research aspects, including established protocols for carotenogenic and
carotenoid-cleavage enzyme characterizations, a large chapter on analytical methods which
meets the need of increasing knowledge on catabolic carotenoid pathways, chapters on how
both anabolic and catabolic pathways can be considered as well as a chapter on imaging
carotenoid storage and carotenogenic metabolon formation in living systems. Finally, we
included practical instructions on how carotenoid metabolism can be altered in model
organisms and how carotenoid function can be assessed in animal systems.
This method collection builds on the willingness of all contributing authors to provide
their detailed lab protocols and make them available to a greater audience which we highly
appreciate. These methods are intended to be used as reference methods to unify research
methods and to allow carotenoid research to be extended into other fields of plant and
animal research. We would like to thank John M. Walker for the invitation to create this
volume of Methods in Molecular Biology and for his careful instructions on the way to
finalize it.
Barcelona, Spain
Manuel Rodrı ´guez-Concepci on
Freiburg, Germany
Ralf Welsch
v