Identification and Content of Astaxanthin and Its Esters from Microalgae Haematococcus pluvialis by HPLC-DAD and LC-QTOF-MS after Extraction with Various Solvents

Abstract

Haematococcus pluvialis, a unicellular green microalga that produces a secondary metabolite under stress conditions, bears one of the most potent antioxidants, namely xanthophyll astaxanthin. The aim of our study was to determine the content of astaxanthin and its esterified forms using three different solvents—methyl tert-butyl ether (MTBE), hexane isopropanol (HEX -IPA) and acetone (ACE)—and to identify them by using high performance liquid chromatography coupled with diode array detection and the quadrupole time-of-flight mass spectrometry (HPLC-DAD and LC-QTOF-MS) technique. We identified eleven astaxanthin monoesters, which accounted for 78.8% of the total astaxanthin pool, six astaxanthin diesters (20.5% of total), while free astaxanthin represented the smallest fraction (0.7%). Astaxanthin monoesters (C16:2, C16:1, C16:0), which were the major bioactive compounds in the H. pluvialis samples studied, ranged from 10.2 to 11.8 mg g−1 DW. Astaxanthin diesters (C18:4/C18:3, C18:1/C18:3) were detected in the range between 2.3 and 2.6 mg g−1 DW. All three solvents were found to be effective for extraction, but MTBE and hexane-isopropanol extracted the greatest amount of free bioactive astaxanthin. Furthermore, MTBE extracted more low-chain astaxanthin monoesters (C16), and hexane-isopropanol extracted more long-chain monoesters (C18 and above) and more diesters. We can conclude that MTBE is the solvent of choice for the extraction of monoesters and hexane-isopropanol for diesters.

Identification of Interacting Proteins of Transcription Factor DpAP2 Related to Carotenoid Biosynthesis From Marine Microalga Dunaliella parva

“…A comprehensive utilization of microalgae could significantly reduce the cost of microalgae biofuels, which included microalgae cultivation using wastewaters in outdoor raceway ponds (Arora et al, 2016;Gao et al, 2018;Keerthana et al, 2020) and the production of bioactive substances such as polysaccharides (Li et al, 2019), antiviral substances (Fritzsche et al, 2021), bioactive peptides (Donadio et al, 2021), and carotenoids (du Preez et al, 2021;Todorovićet al, 2021).…”

The Effect of Combined Elicitation with Light and Temperature on the Chlorogenic Acid Content, Total Phenolic Content and Antioxidant Activity of Berula erecta in Tissue Culture

“…In the future, it would be useful to test several different solvents for the extraction of phenolic compounds from Berula erecta in order to determine the most effective one. In different plant species, the choice of extraction solvent has been shown to influence the amount of bioactive compounds extracted [ 65 , 66 , 67 ]. New trends in chemistry and in environmental legislation have placed demands on the use of so-called “green” extraction processes, so, in the future, it would also be suitable to test the efficiency of extraction with deep eutectic solvents [ 68 ].…”

Astaxanthin Esters as Functional Food: A Review of Their Nutrition, Phytochemical Structure, Biological Features, and Food Industry Prospects

“…Different delivery systems can effectively improve the digestion rate and bioavailability of AST-Es. 44 Yang et al 32 experimentally showed that the bioavailability of AST-E with different molecular structures changed within 24 h, and compared with AST-F and AST-ME, AST-DE had a higher bioavailability at all periods. The bioavailability of AST-Es increases under certain conditions; AST-E bioavailability can be increased by increasing the amount of unsaturated fatty acids.…”

“…The maximum absorption peak of AST liposomes and microemulsions in mouse serum was at 7 h, which was the shortest time compared with the other systems. Different delivery systems can effectively improve the digestion rate and bioavailability of AST-Es . Yang et al experimentally showed that the bioavailability of AST-E with different molecular structures changed within 24 h, and compared with AST-F and AST-ME, AST-DE had a higher bioavailability at all periods.…”