Cyanide formation in preparations fromChlorellaand New Zealand spinach leaves: Effect of added amino acids
✍ Scribed by Hans-Siegfried Gewitz; Elfriede K. Pistorius; Helga Voss; Birgit Vennesland
- Book ID
- 104751700
- Publisher
- Springer-Verlag
- Year
- 1976
- Tongue
- English
- Weight
- 476 KB
- Volume
- 131
- Category
- Article
- ISSN
- 0032-0935
No coin nor oath required. For personal study only.
✦ Synopsis
As part of an effort to identify the natural precursor(s) of H C N in the alga Chlorella vulgaris Beijerinck, and in leaves of New Zealand spinach (Tetragonia expansa, Murr.), H C N release was measured after addition of various amino acids to illuminated algal extracts and grana preparations. Histidine is particularly effective as an H C N precursor, both with Chlorella extracts and leaf grana. With the algal extracts, o-histidine is about ten times more effective than L-histidine and histamine, whereas the two isomers (and histamine) are about equally effective with leaf grana. In the presence of leaf grana plus added Mn 2+ and peroxidase, L-tyrosine and L-cysteine likewise cause H C N formation; but these amino acids cause little or no H C N formation in the presence of Chlorella extracts. A stimulation of H C N production by L-histidine was observed with intact Chlorella cells. Because of the limitations of the assay method, the possibility can not be excluded that other substances than histidine may also lead to H C N generation in Chlorella vulgaris, but the results show that histidine has an important role in H C N generation by this species.