Related Experiment Video
Updated: Aug 23, 2026

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae
Published on: July 10, 2015
Chromium (VI) accumulation reduces chlorophyll biosynthesis, nitrate reductase activity and protein content in
P Vajpayee1, R D Tripathi, U N Rai
1Environmental Botany Laboratory, National Botanical Research Institute, Lucknow, India.
Abstract:
Plants of Nymphaea alba L. grown at various levels of chromium (VI) ranging from 1 to 200 microM accumulated chromium in concentration and duration-dependent manner. At all Cr levels, chromium accumulation by various plant tissues followed the order roots > leaves > rhizomes. Approximately 93% of total chromium present in the medium was accumulated by plants at lowest conentration (1 microM) used in the experiment. Chromium-induced toxicity appears at 1 microM chromium resulting in the build-up of delta-aminolevulinic acid (ALA) and reduced activities of delta-aminolevulinic acid dehydratase (ALAD) and nitrate reductase (NR), total chlorophyll (Chl) and protein contents. Ch1a was more sensitive than Ch1b to chromium toxicity. It could be inferred that chromium toxicity is not located at the level of ALA synthesis, but, probably at the ALAD activity which was more severely affected during chlorophyll biosynthesis. Finally, impaired chlorophyll biosynthesis resulted in reduced total chlorophyll content.
More Related Videos
Related Concept Videos
Adaptations that Reduce Water Loss
The Antenna Complex
Inorganic Nitrogen Assimilation
Red Algae

