We tested the potential of a miniaturized Raman spectrometer for use in field detection of snow algae pigments. A miniature Raman spectrometer, equipped with an excitation laser at 532 nm, allowed for the detection of carotenoids in cells of Chloromonas nivalis and Chlamydomonas nivalis at different stages of their life cycle. Astaxanthin, the major photoprotective pigment, was detected in algal blooms originating in snows at two alpine European sites that differed in altitude (Krkonoše Mts., Czech Republic, 1502 m a.s.l., and Ötztal Alps, Austria, 2790 m a.s.l.). Comparison is made with a common microalga exclusively producing astaxanthin (Haematococcus pluvialis). The handheld Raman spectrometer is a useful tool for fast and direct field estimations of the presence of carotenoids (mainly astaxanthin) within blooms of snow algae. Application of miniature Raman instruments as well as flight prototypes in areas where microbes are surviving under extreme conditions is an important stage in preparation for successful deployment of this kind of instrumentation in the framework of forthcoming astrobiological missions to Mars. Key Words: Snow algae-Chloromonas nivalis-Chlamydomonas nivalis-On-site field detection-Raman spectroscopy-Astaxanthin. Astrobiology 16, 913-924.
- MeSH
- Chlamydomonas chemie MeSH
- Chlorophyta chemie MeSH
- karotenoidy analýza MeSH
- ledový příkrov MeSH
- miniaturizace přístrojové vybavení MeSH
- Ramanova spektroskopie přístrojové vybavení MeSH
- sníh mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Differences in the level of cold acclimation and cryoprotection estimated as ice nucleation activity in snow algae (Chlamydomonas cf. nivalis and Chloromonas nivalis), lichen symbiotic algae (Trebouxia asymmetrica, Trebouxia erici and Trebouxia glomerata), and a mesophilic strain (Chlamydomonas reinhardti) were evaluated. Ice nucleation activity was measured using the freezing droplet method. Measurements were performed using suspensions of cells of A750 (absorbance at 750 nm) ~ 1, 0.1, 0.01 and 0.001 dilutions for each strain. The algae had lower ice nucleation activity, with the exception of Chloromonas nivalis contaminated by bacteria. The supercooling points of the snow algae were higher than those of lichen photobionts. The supercooling points of both, mesophilic and snow Chlamydomonas strains were similar. The lower freezing temperatures of the lichen algae may reflect either the more extreme and more variable environmental conditions of the original localities or the different cellular structure of the strains examined.
HPLC methods (LC-MS/APCI and chiral HPLC) were used for the identification of astaxanthin derivatives from the red snow alga Chlamydomonas nivalis collected in Austrian Alps, Slovak High Tatra Mountains and Bulgarian Pirin. We observed a striking difference in the composition of astaxanthin optical isomers in C. nivalis collected in geographically distinct regions. Furthermore, algae from the Pirin Mountains differed in the dominance of astaxanthin diglucoside diesters, suggesting an alternative strategy to enhance cell viability at low temperatures.
- MeSH
- Chlamydomonas chemie MeSH
- chromatografie kapalinová * MeSH
- estery chemie MeSH
- glukosidy chemie MeSH
- hmotnostní spektrometrie * MeSH
- molekulární struktura MeSH
- nízká teplota MeSH
- stereoizomerie MeSH
- viabilita buněk MeSH
- xanthofyly chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH