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1 Introduction
o. Pulz and K. Scheibenbogen
Together with some photoactive bacteria, mainly procaryotic cyanobacteria as
well as mono- and oligocellular species of eucaryotic classes of Phycophyta
(algae) belonging to the lower plants, are assigned to phototrophic microorganisms. The algae of predominantly aquatic habitat occur in a multitude of shapes
and varieties and together with the phytoplankton of the oceans constitute
approximately one third of the total phytomass production on the earth.
Although the areal concentration of aquatic primary producers is only 0.8% of
the terrestric phytomass (standing crop) of an average of 12.3 kg d.wt. m- 2, their
growth constant and thus their photosynthetic activity exceeds the corresponding efficiencies of higher plants very considerably [1]. Consequently, recalculated protein production potential by phototrophic microorganism amounts
to 96 g protein m - 2 d- 1, which is considerably higher than protein supplied by
agricultural plants like soya [2]. In this connection, microplankton and nanoplankton with cell diameters less than 60 gm represents more than 90% of the
total photosynthetic activity in the seas [3].
Although marine species of higher Phaeophyceae (brown algae), some reaching lengths of 100 m and more, have been used for human nutrition for centuries,
and unicellular organisms or cellular groups are of special biotechnological
interest.
The importance of this microalgae and of microalgal products in general is
reflected in two application fields:
a) Biomass production for the preparation of
- feed for aquacultures (breeding of larvae and bivalves),
- diets or additives for human and animal nutrition (health food, feed additive),
-vitamins, pigments, antioxidants and related biosubstances (carotenoids,
colours, S.O.D.),
- fatty acids and carbohydrates (precursers for pharmaceuticals);
b) Ecological impact to
- environmental technology (e.g. heavy metal fixation, CO2 elimination, lifesupport systems),
- agriculture and eco-systems (soil inoculum, minimization of eutrophy in
waters).
2 Short Review of History
By the middle of this century, the high content of utilizable proteins of more
than 50% gave rise to the idea of using microalgae as a protein source for
human nutrition.
1 Introduction
o. Pulz and K. Scheibenbogen
Together with some photoactive bacteria, mainly procaryotic cyanobacteria as
well as mono- and oligocellular species of eucaryotic classes of Phycophyta
(algae) belonging to the lower plants, are assigned to phototrophic microorganisms. The algae of predominantly aquatic habitat occur in a multitude of shapes
and varieties and together with the phytoplankton of the oceans constitute
approximately one third of the total phytomass production on the earth.
Although the areal concentration of aquatic primary producers is only 0.8% of
the terrestric phytomass (standing crop) of an average of 12.3 kg d.wt. m- 2, their
growth constant and thus their photosynthetic activity exceeds the corresponding efficiencies of higher plants very considerably [1]. Consequently, recalculated protein production potential by phototrophic microorganism amounts
to 96 g protein m - 2 d- 1, which is considerably higher than protein supplied by
agricultural plants like soya [2]. In this connection, microplankton and nanoplankton with cell diameters less than 60 gm represents more than 90% of the
total photosynthetic activity in the seas [3].
Although marine species of higher Phaeophyceae (brown algae), some reaching lengths of 100 m and more, have been used for human nutrition for centuries,
and unicellular organisms or cellular groups are of special biotechnological
interest.
The importance of this microalgae and of microalgal products in general is
reflected in two application fields:
a) Biomass production for the preparation of
- feed for aquacultures (breeding of larvae and bivalves),
- diets or additives for human and animal nutrition (health food, feed additive),
-vitamins, pigments, antioxidants and related biosubstances (carotenoids,
colours, S.O.D.),
- fatty acids and carbohydrates (precursers for pharmaceuticals);
b) Ecological impact to
- environmental technology (e.g. heavy metal fixation, CO2 elimination, lifesupport systems),
- agriculture and eco-systems (soil inoculum, minimization of eutrophy in
waters).
2 Short Review of History
By the middle of this century, the high content of utilizable proteins of more
than 50% gave rise to the idea of using microalgae as a protein source for
human nutrition.