4. Conclutions
Using CQDs as fluorescent probes, we analyzed the changes of
carboxylated biomolecules in the growth and metabolism of Microcystis
aeruginosa by covalent coupling method, mainly including the changes of
GSH, phycocyanin and SOD enzymes in microalgae. The changes of GSH
content in Microcystis aeruginosa at different growth stages and the
correlation between phycocyanin, SOD enzymes and GSH in algal cells were
analyzed from one-dimensional, two-dimensional and three-dimensional
fluorescence, respectively. The correlation was good, and the number of
peaks and peak area of GSH content in the three-dimensional fluorescence
spectral region were changed, and the GSH content in the algal cells
reached the maximum at the 50th day. The GSH content of both phycocyanin
and SOD enzyme reached the maximum at day 65, and there was no other
interference in the system; GSH plays an important role in reducing the
external oxidative damage of microalgae cells. The interaction between
GSH synthesis, GSH/GSSG interconversion, synthesis of phytochelating
peptide (PC), ASA-GSH cycle and metabolism in Microcystis aeruginosa,
and the simultaneous linear changes between GSH and phycocyanin, SOD
enzyme changes all the time, played a key role in maintaining the
antioxidant properties of microalgae during the growth of microalgae and
in regulating redox-sensitive signaling. It plays a key role in the
regulation of redox-sensitive signaling during microalgal growth.