No glycolate oxidase activity could be detected by manometric, isotopic, or spectrophotometric techniques in cell extracts from 5 strains of algae grown in the light with CO(2). However, NADH:glyoxylate reductase, phosphoglycolate phosphatase and isocitrate dehydrogenase were detected in the cell extracts. The serine formed by Chlorella or Chlamydomonas after 12 seconds of photosynthetic (14)CO...

The responses of two species of microalgae, Chlorella sorokiniana and Chlorella zofingiensis, were compared regarding their morphological and biochemical properties under photoautotrophic and mixotrophic conditions. These microalgae were cultured under both conditions, and their crude ethanolic extracts were examined for their pigment and total phenolic contents. In addition, the microalgae's a...

1. The effect of nitrate reduction and assimilation on the CO(2)/O(2) quotient of gas exchange has been used as an index of the relative rates of carbon and nitrogen assimilation in Chlorella pyrenoidosa. Changes in over-all metabolism induced by starvation, high light intensity, and nitrogen deficiency have been studied in comparison with the metabolism of cells growing at light-limiting inten...

The fine structure of pyrenoids from Chlorella pyrenoidosa shows a crystalline matrix with an 8-o-nm periodicity. In certain areas of the pyrenoid 2 sets of parallel lines intersect at approximately 8o° to give a criss-crossed appearance to the matrix. The recognition of the crystalline structure depends on the portion of the pyrenoid that is sectioned, as well as the plane of sectioning. A dis...

The fluorescence transient of Chlorella pyrenoidosa, excited by saturating light absorbed mainly by system II, has a dip D between the peak I at 75 msec and the large peak P at 400 msec (the times depend on light intensity). This dip is observed in aerobic cells and in anaerobic cells where it is prominent. In anaerobic cells, the I-D decline is hastened almost equally by absorption of either 7...

Chlorella sorokiniana (CS) is a unicellular green alga. The extracts of Chlorella have been used as treatments for relieving hypertension and modulating immune response. The detailed mechanisms are not clear yet. In this study, we sought to study the molecular mechanisms for the polysaccharide fraction of CS-induced immune response. We pulsed dendritic cells (DCs) with CS and found that CS coul...

Acetate was incorporated by Chlorella pyrenoidosa into nonvolatile water-soluble compounds (amino acids, organic acids and carbohydrates) with pH optimum between 4 and 5. Incorporation into lipid was maximal at pH 7.5. The proportion of incorporated acetate in lipid was not significantly affected by acetate concentration and chlorophyll concentration in the ranges tested. Illumination of Chlore...

Growth of Chlorella sorokiniana is unaffected by the choice of atmospheric diluent gas. Reduced total pressure has no inhibitory effect and may be slightly stimulatory.

The selective preference of Chlorella pyrenoidosa for alkali metal cations was found to have the order Rb > K > > > Na. It was demonstrated that a cation of higher preference can replace in the cell cations of lower preference by an ion interchange process.The replacement of Na from the cell by K or Rb occurred against high external Na concentrations up to 450 meq/1 Na.It is suggested that the ...