No abstract

No abstract

BackgroundNonalcoholic fatty liver disease (NAFLD) is emerging as the most common liver disease of industrialized countries. Thus, discovering food components that can ameliorate NAFLD is of interest. Lotus root, the edible rhizome of Nelumbo nucifera, contains high levels of polyphenolic compounds, and several health-promoting properties of lotus root have been reported. In this study, we tested whether feeding a polyphenolic extract of lotus root to db/db mice protects them from hepatic steatosis.ResultsAfter 3 weeks of feeding, the hepatomegaly and hepatic triglyceride accumulation were markedly alleviated in the lotus polyphenol-diet-fed db/db mice relative to the control mice. Although the lipolytic enzyme activity was not changed, the activities of lipogenic enzymes, such as fatty acid synthase and malic enzyme, were significantly lower in the lotus polyphenol diet-fed db/db mice. Additionally, the ESI-IT/MS and MALDI-TOF MS spectra revealed the presence of B-type proanthocyanidin polymers with polymerization degree up to 9 in the polyphenolic lotus root extract.ConclusionWe speculate that the condensed tannins contained in lotus root can alleviate hepatic steatosis by suppressing the lipogenic enzyme activity in the livers of db/db mice.

Shochu is traditional Japanese liquor produced from various crops and fungi Aspergillus kawachi or A. awamorii . The amount of unutilized shochu distillation remnants is increasing because of the recent prohibition of ocean dumping of these remnants. In this Article, we first describe the structures of glucosylceramides contained in shochu distillation remnants by fragment ion analysis using ESI-tandem mass spectrometry. Shochu distillation remnant produced from barley contained glucosylceramides d18:2/C16:0h, d18:2/C20:0h, d19:2/C18:1h, and d18:2/C18:0h. Koji (barley fermented with A. kawachii) contained the same glucosylceramides. Shochu distillation remnants produced from rice contained glucosylceramides d18:2/C18:0h and d19:2/C18:1h. The culture broth of A. kawachii contained glucosylceramides d19:2/C18:1h and d19:2/C18:0h. These results indicate that the glucosylceramides contained in crops and those produced by A. kawachii transfer through the processes of fermentation with yeast and distillation to the shochu distillation remnant. This information will enable utilization of shochu distillation remnants and koji as novel sources of sphingolipids.

fIn nature, different microorganisms create communities through their physiochemical and metabolic interactions. Many fermenting microbes, such as yeasts, lactic acid bacteria, and acetic acid bacteria, secrete acidic substances and grow faster at acidic pH values. However, on the surface of cereals, the pH is neutral to alkaline. Therefore, in order to grow on cereals, microbes must adapt to the alkaline environment at the initial stage of colonization; such adaptations are also crucial for industrial fermentation. Here, we show that the yeast Saccharomyces cerevisiae, which is incapable of synthesizing glucosylceramide (GlcCer), adapted to alkaline conditions after exposure to GlcCer from koji cereal cultured with Aspergillus kawachii. We also show that various species of GlcCer derived from different plants and fungi similarly conferred alkali tolerance to yeast. Although exogenous ceramide also enhanced the alkali tolerance of yeast, no discernible degradation of GlcCer to ceramide was observed in the yeast culture, suggesting that exogenous GlcCer itself exerted the activity. Exogenous GlcCer also increased ethanol tolerance and modified the flavor profile of the yeast cells by altering the membrane properties. These results indicate that GlcCer from A. kawachii modifies the physiology of the yeast S. cerevisiae and demonstrate a new mechanism for cooperation between microbes in food fermentation. In nature, microbial communities are formed through metabolic and physiochemical interactions among different microorganisms (1). The pH of cereals that have ripened and dropped from the husk to the ground is neutral to alkaline (2-4). Fermentation microbes, including Saccharomyces cerevisiae, Lactobacillus lactis, and Acetobacter aceti, efficiently utilize carbohydrates in the cereals to produce organic acids (1). As a result, the microbial communities that colonize such carbohydrate-rich cereals, as well as those found in fermented foods, reduce the pH to 4.0 to 6.0. After these microbes establish an acidic pH, they can dominate the environment because they can grow faster at acidic pH values than other microbes. Therefore, these microbes must first adapt to the alkaline environment at the initial stage of colonization on cereal; such adaptation mechanisms are also crucial for industrial fermentation.Traditional alcoholic beverages are produced via the fermentation of cereals by the yeast S. cerevisiae, which can efficiently catabolize glucose to produce ethanol. However, because S. cerevisiae is incapable of hydrolyzing starch to glucose, additional biological catalysts are often added to the fermentation reaction. For example, malt catalyzes starch hydrolysis in wheat-and barleyderived beverages such as whiskey and beer. In East and Southeast Asia, various cereals fermented by fungi are widely used as starchhydrolyzing catalysts for the production of rice-derived alcoholic beverages. These include Japanese sake (5, 6) and shochu, Korean Makgeolli, and Chinese Huangjiu, as well as various other fermented foods ...