Assessment of lipid composition and eicosapentaenoic acid/docosahexaenoic acid bioavailability in fish oil obtained through different enrichment methods.

In this study, we analyzed the eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA) lipid composition of fish oil obtained through enzymatic treatment, fractional distillation and silica gel column purification, and further assessed EPA/DHA bioavailability. Lipid subclass composition information was obtained through ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS), and bioavailability tests were performed using the Caco-2 cell monolayer model. Results showed that enzymatic treatment improved the incorporation of EPA/DHA as diacylglycerol (DG) while silica gel column chromatography enriched the content of EPA/DHA as phosphatidylglycerol (PG) (12.58%) and phosphatidylethanolamine (PE) (4.99%). Furthermore, increasing the purity of EPA/DHA could improve its bioavailability and after 24 incubation, binding forms of triglyceride (TG) was superior to ethyl ester (EE) (p < 0.05) at the same purity level. Those findings are helpful to provide research basis for exploring the bioactivity of fish oil.

Lipidomic analysis and triglyceride profiles of fish oil: Preparation through silica gel column and enzymatic treatment.

A comprehensive study of lipidomic coupled with triglyceride profiles onto four fish oils was performed through ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS). Overall, 1010 lipids belonging to 6 categories and 38 lipid classes were identified. Triglycerides (TGs) were the dominant component in four fish oils (40 %-99 % of total lipids), and glycerophospholipids (GPs) and sphingolipids (SLs) were another two major lipid categories in the fish oil (TG50) which prepared through silica gel column. These results revealed that enzymatic treatment has slight effect on lipid distribution but silica gel column could change the lipids composition. TGs composition of four fish oils were separated completely, and the most TG molecule in TG50 is TG(18:3_14:0_18:0), possessed 13.03 ± 5.07 % relative content, these results implied that silica gel column could protect the nature structure of TGs from destroying which may also limited to further improve eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA) purity, but enzymic method was not restricted by this.

Ginger polysaccharides induced cell cycle arrest and apoptosis in human hepatocellular carcinoma HepG2 cells.

In this study, ginger polysaccharide (GP) was obtained from ginger by enzymatic method, its chemical properties and antitumor activity were investigated. The results indicated that the composition and proportion of GP were l­rhamnose, d­arabinose, d­mannose, d­glucose and d­galactose in a molar ratio of 3.64:5.37:3.04:61.03:26.91, GP had the characteristic absorption peak of polysaccharide. Congo red experiment showed that GP had a triple helix structure, which could have anti-tumor effect. Furthermore, MTT assay, cell morphology observation, nuclear morphology observation and reactive oxygen species observation demonstrated that GP had significant antitumor effect. Flow cytometry suggested that GP could promote apoptosis and arrest cells in G0-G1 phase. Real-time fluorescence quantification and Western blot revealed that GP could up-regulate the expression of Bax, Fas, FasL, caspase-3, p21 and p53, and down-regulate the expression of Bcl-2. These studies suggested that GP would be used as an antitumor drug in foods to promote the development of functional foods.