Novel Synthesis of Phytosterol Ferulate Using Acidic Ionic Liquids as a Catalyst and Its Hypolipidemic Activity.

Phytosterol ferulate (PF) is quantitively low in rice, corn, wheat, oats, barley, and millet, but it is potentially effective in reducing plasma lipids. In this study, PF was synthesized for the first time using acidic ionic liquids as a catalyst. The product was purified, characterized using Fourier transform infrared, mass spectroscopy, and nuclear magnetic resonance, and ultimately confirmed as the desired PF compound. The conversion of phytosterol surpassed an impressive 99% within just 2 h, with a selectivity for PF exceeding 83%. Plasma lipid-lowering activity of PF was further investigated by using C57BL/6J mice fed a high-fat diet as a model. Supplementation of 0.5% PF into diet resulted in significant reductions in plasma total cholesterol, triacylglycerols, and nonhigh-density lipoprotein cholesterol by 13.7, 16.9, and 46.3%, respectively. This was accompanied by 55.8 and 36.3% reductions in hepatic cholesterol and total lipids, respectively, and a 22.9% increase in fecal cholesterol excretion. Interestingly, PF demonstrated a higher lipid-lowering activity than that of its substrates, a physical mixture of phytosterols and ferulic acid. In conclusion, an efficient synthesis of PF was achieved for the first time, and PF had the great potential to be developed as a lipid-lowering dietary supplement.

Tomato seed oil attenuates hyperlipidemia and modulates gut microbiota in C57BL/6J mice.

In this study we aimed to investigate the role of tomato seed oil (TSO) in the alleviation of hyperlipidemia and the regulation of gut microbiota in C57BL/6J mice. Mice were divided into the following four diet-based groups: low-fat diet (LF, n = 8), high-fat diet (HF, n = 6), HF diet with TSO replacing one-third of lard (TL, n = 8), and HF diet with TSO replacing two-thirds of lard (TH, n = 8). The results showed that TH significantly reduced weight gain, relative adipose tissue weights, plasma cholesterol, triacylglycerol, low-density lipoprotein cholesterol (LDL-C), ratio of LDL-C to high-density lipoprotein cholesterol (HDL-C), hepatic cholesterol, and total fatty acids, and markedly increased plasma HDL-C. TSO supplementation also dose-dependently increased fecal cholesterol excretion and reduced fecal total fatty acids. This was accompanied by upregulation of the gene expression of hepatic PPARα, ACADL, CYP7A1, LXRα, ABCA1, and SR-B1. Metagenomic analyses demonstrated that TSO tended to reduce the Firmicutes/Bacteroidetes ratio, significantly increased the relative abundance of the genus Lactobacillus, and reduced the relative abundance of the genera Rikenella, Enterorhabdus, unclassified_o_Clostridiales and Ruminococcaceae_UCG-009. These results proved that TSO was effective in attenuating hyperlipidemia in C57BL/6J mice by enhancing fatty acid ß-oxidation, reducing cholesterol absorption, promoting cholesterol efflux, and favorably modulating the gut microbiota.

Candida sp. 99-125 lipase-catalyzed synthesis of ergosterol linolenate and its characterization.

As a major sterol in edible mushroom, ergosterol has gained much attention owing to its potential bioactivities. However, ergosterol has a high melting point, poor oil solubility and stability, which restrict its scope of application. In this study, an ergosterol ester of α-linolenic acid was successfully and efficiently prepared using Candida sp. 99-125 lipase as a biocatalyst. The desired product was confirmed to be ergosterol linolenate using MS, FT-IR, and NMR analyses. Using Candida sp. 99-125 lipase, the product conversion exceeded 92% in 12 h under the following optimized parameters: 75 mmol/L ergosterol, 40 g/L lipase, 1:1.25 ergosterol-to-α-linolenic acid molar ratio, and 45 °C. The results confirmed that Candida sp. 99-125 lipase has good reusability and stability and is also relatively low cost, suggesting its great potential for large-scale production of ergosterol ester. Most importantly, the physiochemical properties (oil solubility and melting point) of ergosterol significantly improved after esterification with α-linolenic acid, thus facilitating its application in oil-based systems.