Chemical Transformation of Astaxanthin from Haematococcus pluvialis Improves Its Antioxidative and Anti-inflammatory Activities

Abstract

Astaxanthin is a strong antioxidant, but the effect of esterification on its biological activities remains unclear. Here, we chemically synthesized three forms of astaxanthin (nonesterified (Ast-N), monoesterified (Ast-mE), and diesterified (Ast-dE) forms) using esterified astaxanthin (Ast-E) in natural extract from Haematococcus pluvialis and characterized them by spectrophotometry and high-performance liquid chromatography (HPLC). Additionally, the antioxidant and anti-inflammatory activities of the samples containing three forms of astaxanthin at different ratios were evaluated. The sample containing the maximum level of Ast-mE compared to those of Ast-N and Ast-dE showed the highest antioxidant and anti-inflammatory activities. We also observed the greatest increase in expression of genes related to antioxidant and anti-inflammatory effects in samples containing the highest Ast-mE. These results provide a foundation for in-depth investigation of astaxanthin and other antioxidant molecules, allowing for the development of a practical and cost-effective strategy to improve antioxidant or anti-inflammatory activities of natural extracts that can be used as dietary supplements.

Comparison of Different Methods for Extracting the Astaxanthin from Haematococcus pluvialis: Chemical Composition and Biological Activity

“…It was observed that pre-treating normal fibroblast cells with AST increased the cell viability in a dosedependent manner attesting its antioxidant power. Furthermore, Nagaraj, Rajaram [31] analyzed the cell viability by MTT assay with different concentrations of AST (5,10,15,20, and 25 µg/mL) to incubate at different periods. The results indicated that the AST (25 µg/mL) significantly obstructs the HepG2 cancer cell growth and induces cell apoptosis.…”

“…For biological activity, AST can significantly decrease oxidative stress and free radicals. AST has several nutraceutical and human health-promoting applications including in the anti-proliferation, anti-inflammatory, anti-cancer, and cardiovascular systems [5,[10][11][12]. With increasing demand, AST will be one of the important microalgal products in the future [5].…”

Anticancer Activity of Astaxanthin-Incorporated Chitosan Nanoparticles

“…In particular, its biological activities, such as pigmentation, ultraviolet (UV) light protection, immune response, antioxidative effects, reproductive capacity, and stress tolerance, have been spotlighted in the field of the biomedical and health food additive industries [ 5 ]. The biological activity of AST is basically related to a hydroxyl group and a keto group on each end of its chemical structure; its peculiar features promote human health [ 6 , 7 ]. In particular, unique chemical structures enable it to scavenge reactive species of oxygen or nitrogen, i.e., polar end groups and double bonds of the middle segment are contributed to quench free radicals and remove high-energy electrons, respectively [ 7 , 8 ].…”

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

“…Astaxanthin occurs naturally either in unesterified (yeast) or esterified form (algae). In H. pluvialis it is found mainly in esterified form as monoester bound to short-chain fatty acids [19][20][21]. Approximately 70% of the astaxanthin pool of H. pluvialis with enzyme formation are monoesters, 25% diesters, and 5% free astaxanthin, predominantly in 3S,3S' form [22].…”

“…Astaxanthin has been quantified by various analytical methods, such as HPLC-DAD [8,12,16,18,21,23] and LC-(APCI)MS [24][25][26]. Castillo et al [27] focused on environmentally friendly solid phase dispersion (MSPD) extraction with ethanol, ethyl lactate and water where they obtained three new acids, determined some astaxanthin monoesters and no diester.…”