Bioavailability of acetate from two vinegar supplements: capsule and drink.

The bioavailability of acetate in various vinegar supplements, e.g. as capsules and drinks, remains unclear.

Preparation of (13)C-labeled ceramide by acetic acid bacteria and its incorporation in mice.

We prepared 2-hydroxypalmitoyl-sphinganine (dihydroceramide) labeled with a stable isotope by culturing acetic acid bacteria with (13)C-labeled acetic acid. The GC/MS spectrum of the trimethylsilyl derivative of (13)C-labeled dihydroceramide gave molecular ions with an increased mass of 12-17 Da over that of nonlabeled dihydroceramide. The fragment ions derived from both sphinganine base and 2-hydroxypalmitate were confirmed to be labeled with the stable isotope in the spectrum.

Effect of continuous ingestion of acetic Acid bacteria on memory retention and the synaptic function in aged rats.

We administered Acetobacter malorum NCI1683 (S24), containing a high concentration of dihydroceramide (7.2 mg/g of dry cell weight), consecutively to aged rats (male Crlj:Wistar rats, 22 months old). The ingestion of Acetobacter malorum for 89 d significantly extended the memory retention in passive avoidance tests, increased the release of acetylcholine with depolarization of brain synaptosomes and decreased the causative agents of neurodegenerative diseases in the cerebral cortices.

Cloning and characterization of clpB in Acetobacter pasteurianus NBRC 3283.

The clpB gene in Acetobacter pasteurianus was cloned and characterized. Although the clpB gene was transcribed in response to a temperature shift and exposure to ethanol, the clpB disruption mutant was only affected by high temperature, suggesting that the ClpB protein is closely associated with heat resistance in A. pasteurianus.

Vinegar intake enhances flow-mediated vasodilatation via upregulation of endothelial nitric oxide synthase activity.

This study examined the effect of acetate on endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVECs) by immunoblotting assay and the ability of acetic acid to upregulate flow-mediated vasodilatation in humans. In HUVECs, acetate induced a biphasic increase in the phosphorylated form of eNOS. The amount of phosphorylated eNOS was significantly increased by exposure to 200 mumol/l acetate for 20 min (early phase) and for 4 h (late phase).

Acetic acid bacterial lipids improve cognitive function in dementia model rats.

Acetic acid bacteria, fermentative microorganisms of traditional foods, have unique alkali-stable lipids (ASL), such as dihydroceramide which is a precursor of sphingolipids. Sphingolipids are important components of the brain tissue. We examined the effect of oral administration of ASL in a rat model of dementia (7-week-old, male) with a basal forebrain lesion.

Fermentation and metabolic characteristics of Gluconacetobacter oboediens for different carbon sources.

The metabolism of Gluconacetobacter oboediens was investigated in relation to different carbon sources for the continuous cultures at the dilution rate of 0.05 h(-1). The 13C-flux result implies the formation of metabolic recycles for the case of using glucose and acetate as carbon sources.

Elevation of ceramide in Acetobacter malorum S24 by low pH stress and high temperature stress.

Acetic acid bacteria have unique and highly pure membrane lipid components, such as 2-hydroxypalmitoyl-sphinganine (dihydroceramide) and can grow and produce acetic acid at around pH 3.0, suggesting that ceramide in cell membranes may be involved in the tolerance to acidic pH. Acetobacter malorum S24 was selected for the production of ceramide and grown in YPG medium containing 0.

Cloning and characterization of grpE in Acetobacter pasteurianus NBRC 3283.

The grpE gene in Acetobacter pasteurianus NBRC 3283 was cloned and characterized, to elucidate the mechanism underlying the resistance of acetic acid bacteria to the stressors existing during acetic acid fermentation. This gene was found to be located in tandem with two related genes, appearing on the genome in the order grpE-dnaK-dnaJ. A sigma(32)-type promoter sequence was found in the upstream region of grpE.

Vinegar intake reduces body weight, body fat mass, and serum triglyceride levels in obese Japanese subjects.

Acetic acid (AcOH), a main component of vinegar, recently was found to suppress body fat accumulation in animal studies. Hence we investigated the effects of vinegar intake on the reduction of body fat mass in obese Japanese in a double-blind trial. The subjects were randomly assigned to three groups of similar body weight, body mass index (BMI), and waist circumference.

Acetic acid upregulates the expression of genes for fatty acid oxidation enzymes in liver to suppress body fat accumulation.

We investigated the effect of acetic acid (AcOH) on the prevention of obesity in high-fat-fed mice. The mice were intragastrically administrated with water or 0.3 or 1.

Acetic acid activates PKD1L3-PKD2L1 channel--a candidate sour taste receptor.

The polycystic kidney disease (PKD) 1L3-PKD2L1 channel is a candidate sour taste receptor expressed in mammalian taste receptor cells. Various acids are reported to activate PKD channels after the removal of the acid stimuli, but little information is available on the activation of these channels by acetic acid. It was difficult to analyze the PKD channel activation by acetic acid using Ca2+ imaging experiments because this acid induces a transient and nonspecific response in cultured cells.

Hydrogen peroxide resistance of Acetobacter pasteurianus NBRC3283 and its relationship to acetic acid fermentation.

The bacterium Acetobacter pasteurianus can ferment acetic acid, a process that proceeds at the risk of oxidative stress. To understand the stress response, we investigated catalase and OxyR in A. pasteurianus NBRC3283.

Identification of two major ammonia-releasing reactions involved in secondary natto fermentation.

Natto is a traditional Japanese food made from soybeans fermented by strains of Bacillus subtilis natto. It gives off a strong ammonia smell during secondary fermentation, and the biochemical basis for this ammonia production was investigated in this study. When natto was fermented by strain r22, ammonia production was shown to involve degradation of soybean proteins releasing amino acids, and only the glutamate contained in the natto obviously decreased, while the other amino acids increased during secondary fermentation.