Bioactive Lipids of Marine Microalga Chlorococcum sp. SABC 012504 with Anti-Inflammatory and Anti-Thrombotic Activities

Abstract

Microalgae are at the start of the food chain, and many are known producers of a significant amount of lipids with essential fatty acids. However, the bioactivity of microalgal lipids for anti-inflammatory and antithrombotic activities have rarely been investigated. Therefore, for a sustainable source of the above bioactive lipids, the present study was undertaken. The total lipids of microalga Chlorococcum sp., isolated from the Irish coast, were fractionated into neutral-, glyco-, and phospho-lipids, and were tested in vitro for their anti-inflammatory and antithrombotic activities. All tested lipid fractions showed strong anti-platelet-activating factor (PAF) and antithrombin activities in human platelets (half maximal inhibitory concentration (IC50) values ranging ~25–200 μg of lipid) with the highest activities in glyco- and phospho-lipid fractions. The structural analysis of the bioactive lipid fraction-2 revealed the presence of specific sulfoquinovosyl diacylglycerols (SQDG) bioactive molecules and the HexCer-t36:2 (t18:1/18:1 and 18:2/18:0) cerebrosides with a phytosphingosine (4-hydrosphinganine) base, while fraction-3 contained bioactive phosphatidylcholine (PC) and phosphatidylethanolamine (PE) molecules. These novel bioactive lipids of Chlorococcum sp. with putative health benefits may indicate that marine microalgae can be a sustainable alternative source for bioactive lipids production for food supplements and nutraceutical applications. However, further studies are required towards the commercial technology pathways development and biosafety analysis for the use of the microalga.

One-step separation system of bio-functional lipid compounds from natural sources

“…It should be stressed that specific PLs belonging to the glycolipids and phopsholipids’ subclasses that are present in several natural sources (such as animal and marine sources, plants, microorganisms of biotechnological and agricultural interests, foods, beverages and related products and by-products), have been found to possess strong anti-platelet, anti-thrombotic and anti-inflammatory effects against inflammatory and thrombotic mediators like PAF and thrombin, but also against well established platelet agonists like adenosine diphosphate (ADP) and collagen [1 , [3] , [4] , [5] , [6] , [7] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] . By such favorable bio-functionalities, these PLs have also exhibited promising outcomes against several inflammation-related chronic disorders, such as atherosclerosis and CVD, renal disorders, cancer, persistent infections (i.e.…”

“…Bioactive PL molecules include but are not limited to the following: (i) phospholipids, such as phosphatidylcholines (PC), phosphatidylethanolamines, sphingomyelins (SM), and especially PAF-like molecules and/or those bearing ω3 PUFA in the sn -2 position of their structures, (ii) glycolipids, such as sulphoquinovosyldiacylglycerols (SQDG), mono/di-galactosyldiacylglycerols (MGDG/DGDG) and mono/di-glycodiacylglycerols, including glycolipids with palmitic acid at the sn -1 position and ALA/EPA/DHA esterified at the sn -2 position of their structures), (iii) cerebrosides and gangliosides, and (iv) other bioactive polar compounds such as phenolic compounds and phenol-lipids that usually migrate to the PL fraction of several separation procedures [1] , [3] , [4] , [5] , [6] , [7] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] .…”

“…Traditionally, TLs are obtained from a natural source, either by extraction (by using conventional methods of extraction such as the Bligh & Dyer method [6 , 18 , 30] or food grade ones [7] ), or by applying other mechanical methods, such as specific pressure and temperature conditions during supercritical fluid extraction (SFE), subcritical water extraction (SWE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) [31] . Then, these TL preparations are usually further separated into the PL and NL subclasses by applying classic methods of lipid analysis, such as counter current distribution (CCD) by using conventional solvents [33] or food grade solvents and methodology [7] , liquid column chromatography (LC), solid phase extractions (SPE), thin layer chromatography (TLC) in one or two dimensions (1D or 2D respectively), high pressure (performance) liquid chromatography (HPLC) of analytical grade, and several other similar methods [5] , [6] , [7] , 10 , 11 , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [34] , [35] , [36] , [37] , [38] .…”

“…After obtaining the TL-extract from a natural source, these TLs are usually further separated into the PL and NL subclasses by applying classic methods of lipid analysis, such as CCD, LC, SPE, TLC, HPLC of analytical grade, and other similar methods [5] , [6] , [7] , 10 , 11 , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [30] , [31] , [33] , [34] , [35] , [36] , [37] , [38] , in any order. Such a traditional approach usually demands specific expertise and comprises of several costly, repetitive and time-consuming steps.Ιn several cases the guard pre-columns and even the column itself are saturated by bulky lipid samples that reduce the efficacy of the separation, and thus the use of analytical grade HPLC columns is further compromised.…”

Microalgal Lipid Extracts Have Potential to Modulate the Inflammatory Response: A Critical Review

“…The lipidomic profile of several microalgae species have been studied, and significant polar lipids, represented in Figure 3 , that have been identified include species from several classes of phospholipids, such as phosphatidic acid (PA), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC), phosphatidylglycerol (PG); glycolipids, such as digalactosyldiacylglycerol (DGDG), sulfoquinovosylmonoacylglycerol (SQDG), monogalactosyldiacylglycerol (MGDG); and betaines lipids, such as diacylglyceroltrimethylhomoserine (DGTS), diacylglyceryl hydroxymethyl-N,N,N-trimethyl-β-alanine (DGTA), and diacylglyceryl carboxyhydroxy methyl-choline (DGCC), as represented in Figure 3 . Some of the polar lipid species described here were reported as being biologically active [ 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”