Improved effects of okara atomized by a water jet system on α-amylase inhibition and butyrate production by Roseburia intestinalis

ABSTRACT

Improving the physicochemical properties of okara for various applications in foods is of great importance. Here, okara and microcrystalline cellulose (MCC) were atomized using a water jet (WJ) system. The WJ-treated okara and MCC dispersed homogeneously in water, and their median sizes in particle size distribution were 6.6 μm and 9.5 μm, respectively. The dispersions of WJ-treated okara and MCC showed high apparent viscosity and shear thinning behavior. Moreover, the inhibition of α-amylase activities by WJ-treated okara was more effective than that by untreated MCC and cellulose. Furthermore, the production of short-chain fatty acids by 32 dominant species of human gut microbes was determined. An increase in butyrate production by Roseburia intestinalis was observed in the presence of WJ-treated okara, but not in untreated okara or WJ-treated MCC. These results demonstrate that WJ system can be used on okara to increase inhibited α-amylase activities and butyrate production by gut microbiota.     

Chromones from Harrisonia perforata

Five new chromones, perforatins C-G, together with 10 known compounds were isolated from the wood of Harrisonia perforata.     

Gonadal Estrogen Profile and Immunohistochemical Localization of Steroidogenic Enzymes in the Oyster and Scallop during Sexual Maturation

Estrogen levels in the gonads of marine bivalves, the Pacific oyster Crassostrea gigas and scallop Patinopecten yessoensis were determined by high performance liquid chromatography (HPLC) using an electrochemical detector. Estrone (E₁), estradiol-17β (E₂), and a small amount of estriol (E₃) were identified in the ovary, while only E₂ was found in the testis. The level of E₂ in the ovary was consistently higher than E₁ and it increased with sexual maturation. These results indicate that E₂ may play a role in the reproductive events of the oyster and scallop. In vitro experiments demonstrated the presence of 17β-hydroxysteroid dehydrogenase (17β-HSD) in the ovaries of both bivalves. The activity of 17β-HSD in the ovary was lower in the postspawning stage than in the early differentiating stage. The evidence for the presence of aromatase activity in the scallop ovary was obtained by ³H-water assay. The immunoreactivity against 3β-hydroxysteroid dehydrogenase (3β-HSD), P450 aromatase and E₂ was detected in the cells along the outside of germinal acini of the scallop ovary. It is concluded that estrogens can be synthesized in the gonad, that their levels vary with the reproductive cycle, and that they have a role in the development of gametes.     

Assessment ofGibberella fujikuroi mating type by PCR

Mating type (MAT)-specific fragments of the two idiomorphs ofGibberella fujikuroi (anamorph,Fusarium moniliforme) were obtained by PCR amplification using primers to conserved regions ofMAT homologs from other fungal species and used to assign mating type by molecular criteria rather than the arbitrary historical designation. Mating type—strains of mating populations A-E and a mating type+strain of mating population F carry an α-box motif and should therefore be designatedMAT-1. Mating type+strains of mating populations A-E and a mating type—strain of mating population F carry an HMG-box motif and should be designatedMAT-2. Thus, assessment of mating type ofG. fujikurol strains can be easily achieved usingMAT-specific primers.     

A cadmium-binding protein in rat liver identified as ornithine carbamoyltransferase.

A cadmium-binding protein of Mr about 40,000 (40K Cd-BPa) was detected in rat liver by Western blotting [Aoki, Kunimoto, Shibata & Suzuki (1986) Anal. Biochem. 157, 117-122]. It was characterized and identified as ornithine carbamoyltransferase (OCTase, EC 2.1.3.3) on the basis of coincidence of their physicochemical and enzymological features. The amino acid sequence of the N-terminal and those of three tryptic digests in 40K Cd-BPa were identical with those of OCTase. The Mr values of the denatured and native forms of 40K Cd-BPa (39,000 and 110,000 respectively) were the same as those of OCTase. 40K Cd-BPa showed, as OCTase activity, a specific activity of 230 mumol/min per mg of protein and Km of 0.6 mM for ornithine, this value also being essentially the same as that for OCTase. A rabbit antibody against OCTase reacted with 40K Cd-BPa. The native form of 40K Cd-BPa bound to 0.8 molar equiv, of cadmium, with a dissociation constant of 7.6 x 10(-6) M.     

The effect of degradation on κ-carrageenan/locust bean gum/konjac glucomannan gels at acidic pH

The feasibility of textural and rheological modification of gels containing κ-carrageenan (KC) and locust bean gum (LBG) by addition of konjac glucomannan (KGM) was investigated. Special attention was paid to the effect of polysaccharide degradation during heating at acidic pH. The general effect of polysaccharide degradation was to decrease the Young's modulus, while the fracture strain in extension was scarcely affected unless the degradation was very severe.     

Hemoglobin-mediated selenium export from red blood cells

On the basis of the fact that selenium from selenite binds to hemoglobin (Hb), we investigated the missing process in the selenium export from red blood cells (RBCs), i.e., the transfer of selenium bound to Hb to RBC membrane proteins. To elucidate the molecular events of the Hb-associated selenium export from RBC, a Hb–Se complex was synthesized from thiol-exchange of Cys-β93 in Hb with penicillamine-substituted glutathione selenotrisulfide, as a model of major metabolic intermediates, and then interactions between the Hb–Se complex and RBC inside-out vesicles (IOVs) were examined. Selenium bound to Hb was transferred to the IOV membrane on the basis of the intrinsic interactions between Hb and the cytoplasmic domains of band 3 protein (CDB3). The observed selenium transfer was inhibited by the pretreatments of IOVs with iodoacetamide and the α-chymotrypsin digestion, indicating that the Hb mediates the selenium transfer to the thiol groups of CDB3. In addition, it was found that deoxygenated Hb, with a high binding affinity for CDB3, more favorably transferred selenium to the IOV membranes than oxygenated Hb, with a low affinity. When selenium export from RBC to the plasma was examined by continuously introducing nitrogen gas, the selenium export rate was promoted with an increase in the rate of deoxygenated Hb. Overall, these data suggested that Hb could possibly play a role in the selenium export from RBC treated with selenite in an oxygen-linked fashion. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Fibroblast growth-stimulating activity of S100A9 (MRP-14).

Fibroblasts play a critical role in chronic inflammation and wound healing. In this study, a fibroblast growth-stimulating factor was purified from the exudate of carrageenan-induced inflammation in rats. The purified protein was a disulfide-linked homodimer. Amino acid sequence analysis of the peptides generated by cleavage with cyanogen bromide and proteinase V8 resulted in identification of the protein as S100A9. Recombinant S100A9 as well as its disulfide-linked homodimer stimulated the proliferation of fibroblasts at a similar concentration of the purified protein. The concentration of S100A9 in the exudate was determined by immunoblot analysis. The total protein concentration in the exudate reached a maximum 4 days after carrageenan injection and then slightly decreased, whereas the concentration of S100A9 reached a maximum at day 3 and then decreased rapidly. These studies show that S100A9 is present at a high concentration in the exudate of carrageenan-induced inflammation in rats, and that S100A9 stimulates proliferation of fibroblasts, suggesting that it plays a role in chronic inflammation.