Effects of different cultivation conditions on the production of β-cyclocitral and β-ionone in Microcystis aeruginosa

Abstract

Background Cyanobacteria blooms have become a major environmental problem and concern because of secondary metabolites produced by cyanobacteria released into the water. Cyanobacteria produce volatile organic compounds (VOCs), such as the compounds β-cyclocitral and β-ionone, which comprise odors, off-flavors, defense compounds, as well as growth regulators. Therefore, the general objective of this work was to evaluate the VOCs produced by two strains of Microcystis aeruginosa, differing in their ability to produce microcystins (LTPNA 01—non-producing and LTPNA 08—toxin-producing). The analysis of VOC production was carried out in (1) normal culture conditions, (2) under different light intensities (LI), and (3) after the external application of β-ionone in both cultures. Results The results showed that β-cyclocitral and β-ionone are produced in all growth phases of LTPNA 01 and LTPNA 08. Both strains were producers of β-cyclocitral and β-ionone in normal culture conditions. It was observed that the β-cyclocitral concentration was higher than β-ionone in all light intensities investigated in this study. Additionally, the strain LTPNA 01 produced more β-cyclocitral than LTPNA 08 at almost all times and LIs analyzed. However, the strain LTPNA 08 produced more β-ionone, mainly at the initial times. In addition, the experiment results with the external addition of β-ionone in the cultures showed that the strain LTPNA 01 produced more β-cyclocitral in control conditions than in treatment. Nonetheless, β-ionone production was higher in treatment conditions in LTPNA 08, indicating that the addition of β-ionone may favor the production of these compounds and inhibit the production of β-cyclocitral. Conclusion Our results showed that some abiotic factors, such as different light intensities and external application of β-ionone, can be triggers that lead to the production of VOCs.

β-Cyclocitral: Emerging Bioactive Compound in Plants

“…Enzymatic action produces CCD4b from the genetic variance of Crocus sativus through β-carotene cleavage in the model plant Arabidopsis, which hastens to reduce the dehydration, salinity and oxidation rate [ 40 , 52 ]. The endo-metabolic substances in vascular plants took part in the xenobiotic response with diverse detoxifying agents, such as SCL14, ANAC102, ANAC001 and ANAC031 for oxidation resistance [ 11 ]. The βCC induced plants build interdependence with PAP signaling and down-regulate carotenoid substances while ST2A acts as a sulfate donor, and SAL1 has a deleterious effect during the plethora of light and drought stress [ 53 , 54 ].…”

“…Poly-unsaturated fatty acid oxidation is found to function as a co-substrate for performing enzymatic activities [ 8 , 9 ]. Interestingly, βCC contain vital apocarotenoids of β-carotene [ 10 ] that play important roles under abiotic stress conditions [ 11 , 12 ]. Plant genomic effect, apoptosis, gene activation processes, and transcription activation are encountered due to low RES and excess ROS oxidation [ 13 , 14 , 15 ].…”