Algae are a very large and diverse group of autotrophic organisms which ranges from unicellular to multicellular forms. They are primary producers which is a source of many nutrients and it has high protein content. The most complex marine forms are called seaweeds. Blue green algae ,red algae, green algae assigned higher contents of dietary fibres. Certain beverages are prepared from sea algae...

Four paddy fields in Guilan province in the north of Iran seasonally were sampled from April 2008 to January 2009. Twenty-two morphospecies belonging to three families of the heterocystous blue-green algae were identified. Fourteen species and one variety of these taxa are new record for Iran. Among the families Nostocaceae with six genera and 16 species showed the highest species richness.

Action spectra for delayed light production by several algae were determined from 250 to 750 mmicro incident light. In the visible portion of the spectrum the action spectra resemble those reported by previous workers for photosynthesis and light emission. Blue-green algae had a maximum at 620 mmicro, red algae at 550 mmicro, whereas green and brown algae have action spectra corresponding to ch...

Z. Naturforsch. 46c, 542-548 (1991); received February 13, 1991 Blue-Light Photoreceptor, Chlorophyll Synthesis, Desmarestia aculeata, Green-Light Photo­ receptor, Nitrate The chlorophyll synthesis in the brown algae Desmarestia aculeata is affected by light quali­ ty and by the nutrient state in the medium before the illumination. Pulses of 5 min of red, green and blue light together with 200 ...

Blue-green algal mats incubated anaerobically rapidly produce large amounts of volatile sulfur compounds, including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. The major organic sulfur compound is methyl mercaptan, in contrast to previous results with marine eucaryotic algae. Light inhibited production of volatile sulfur compounds, apparently because the algae then produced O2, re...