ISSN:
1438-3888
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Description / Table of Contents:
Zusammenfassung 1. Es wird ein einfaches Verfahren zur Gewinnung größerer, für chemisch-analytische Untersuchungen ausreichender Zellsaftmengen auch von kleinzelligen Meeresalgen beschrieben. 2. Eine neue Methode zur Bestimmung des AFS von Meeresalgen mit Hilfe seewasserisotonischer LiCl-Lösungen wird am Beispiel vonChaetomorpha linum kritisch untersucht. 3. Unter Berücksichtigung der an einigen Helgoländer Meeresalgen bestimmten Li-AFS-Werte werden aus den Ergebnissen der chemischen Analysen die Zellsaftkonzentrationen der nachgewiesenen Ionen berechnet. 4. Die Voraussetzungen für die Zuverlässigkeit der erzielten Ergebnisse werden im Zusammenhang mit Befunden anderer Autoren diskutiert.
Notes:
Abstract Samples of cell sap in amounts suitable for chemical analysis of mineral compounds were obtained by high speed centrifugation of several frost-killed (-20° C) Helgoland algae under paraffin oil. In order to calculate the vacuole concentration of the mineral salts determined in these liquids, the extravacuolar solving space of the algae was measured as Lithium apparent free space (Li-AFS) after rinsing the algae for several minutes in balanced LiCl solutions. The Li-AFS was calculated from the results gained by flamephotometric determination of the Li-concentrations in the sap and in the bathing fluid. To avoid errors caused by interaction of Donnan-effects, the Li-AFS ofChaetomorpha linum kept in diluted sea water of different concentrations was measured. By plotting the results against the medium concentration, evidence was obtained to show that in 100 % Li-solution (corresponding osmotically to natural sea water of about 30 ‰), the Donnan effect was negligible. In the more diluted solutions, however, higher Li-AFS values were obtained. This would indicate that the differences in the distribution of Li-cations between medium and AFS, which are effected by the negative charges of indiffusible anions in the cytoplasm and of fixed acidic groups (e. g. R-COO−) of phycocolloids in the wall material, will cause considerable errors if Li-concentrations are too low. Taking these experiences into account, AFS-values of several algae from Helgoland were measured by the same technique and the vacuole concentrations of the analysed mineral compounds calculated.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01612374
