Sake lees extract improves hepatic lipid accumulation in high fat diet-fed mice.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is increasing worldwide as one of the leading causes of chronic liver disease. Sake lees (SL) are secondary products of sake manufacturing and are considered to have beneficial effects on human health. To investigate these effects, we used high fat diet (HFD)-fed mice treated with or without the SL extract. METHOD: Mice were the HFD ad libitum for 8 weeks and were administered 500 µL of distilled water with or without the SL extract (350 mg/mL) by a feeding needle daily for the last 4 weeks. Food intake, body weight, and liver weight were measured. Triacylglycerol content and the mRNA and protein expression levels of various lipid and glucose metabolism-related genes were determined in liver tissues. The levels of triglyceride, free fatty acids, glucose, insulin, and liver cell damage markers were determined in serum. Fatty acid-induced lipid accumulation in HepG2 cells was assessed in the presence or absence of the SL extract. RESULTS: Mice fed a HFD and treated with the SL extract demonstrated a significant reduction in hepatic lipid accumulation and mRNA and protein levels of peroxidome proliferator-activated receptor γ (PPARγ), PPARα, CD36, and phosphoenolpyruvate carboxykinase 1 in the liver, while the SL extract did not affect body weight and food intake. Moreover, insulin resistance and hepatic inflammation in HFD-fed mice improved after administration of the SL extract. In HepG2 cells, the SL extract suppressed fatty acid-induced intracellular lipid accumulation. CONCLUSIONS: These findings suggest that treatment with the SL extract could potentially reduce the risk of NAFLD development, and that the SL extract may be clinically useful for the treatment of NAFLD.

Production of the natural iron chelator deferriferrichrysin from Aspergillus oryzae and evaluation as a novel food-grade antioxidant.

BACKGROUND: Deferriferrichrysin (Dfcy) is a siderophore found in foods fermented by Aspergillus oryzae and is a promising candidate for an antioxidant food additive because of its high binding constant toward iron. However, the Dfcy concentration is typically low in foods and cultures. RESULTS: We optimised culture conditions to improve Dfcy production to 2800 mg L(-1) from 22.5 mg L(-1) under typical conditions. Then, we evaluated the potential of Dfcy as a food additive by measuring its safety, stability, and antioxidant activity. Dfcy was sufficiently stable that over 90% remained after pasteurisation at 63 °C for 30 min at pH 3-11, or after sterilisation at 120 °C for 4 min at pH 4-6. Dfcy showed high antioxidant activity in an oil-in-water model, where inhibition of lipid oxidation was measured by peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) assays. Dfcy decreased PV and TBARS by 83% and 75%, respectively. Antioxidant activity of Dfcy was equal to or higher than that of the synthetic chelator EDTA. CONCLUSION: Our study provides the first practical method for production of Dfcy. Dfcy can be a novel food-grade antioxidant and the first natural alternative to the synthesised iron chelator EDTA. © 2015 Society of Chemical Industry.

Iron chelated cyclic peptide, ferrichrysin, for oral treatment of iron deficiency: solution properties and efficacy in anemic rats.

Ferrichrysin (Fcy), which is produced by Aspergillus oryzae and is present in foods used for human consumption, belongs to a group of hydroxamate siderophore ferric iron chelators. Fcy (100 mg/mL) dissolves completely at both pH 2.0 and 7.0, being very stable at a wide range of pH, high temperatures and pressures, with little reactivity to dietary iron absorption inhibitors, phytic acid, tannic acid, and catechin. We studied the effect of Fcy in male Sprague-Dawley rats with iron-deficiency anemia, which were separated into three different dietary groups (n=5) and supplementing diets as follows: (i) ferric citrate, (ii) heme iron concentrate, and (iii) Fcy (35 mg Fe/kg diet) for three weeks. Fcy exhibited the same beneficial effect in improving iron deficiency anemia as ferric citrate, being significantly greater than the effect of heme iron. The iron concentration of liver in the Fcy group was 35% greater than that in the ferric citrate group. These findings indicate that Fcy could be an efficient oral iron supplement to prevent or treat iron deficiency.