This paper reports the effect of temperature on the production characteristics of soybean oil-in-water (O/W) emulsions by microchannel (MC) emulsification using different emulsifiers. The temperature of an emulsification module including an MC array chip (MS104) was controlled between 10°C and 70°C. Sodium oleate, pentaglycerol monolaurate (PGM), and polyoxyethylene sorbitan monolaurate (Tween 20) were used as emulsifiers. The contact angle of the dispersed phase on the channel wall exceeded 130° and decreased gradually as the temperature increased. Monodisperse O/W emulsions with coefficients of variation (CV) below 6% were produced, independent of the temperature applied and the type of emulsifier used. The resultant droplet diameters, which ranged between 30 μm and 36 μm, decreased gradually as the temperature increased. The resultant droplet diameter was also almost constant below a critical flow velocity of the dispersed phase in a channel. The critical flow velocity increased with increasing operating temperature. The sodium oleate-containing system had a critical flow velocity and a maximum droplet generation rate considerably higher than those for Tween 20- and PGM-containing systems at each temperature.
A simple high-yield method for purifying 3,4,5-tri-O-caffeoylquinic acid from sweetpotato leaves (Ipomoea batatas L.) was established. The method consisted of methanol extraction, water-hexane partition, MCI gel CHP20P, and Sephadex LH-20 chromatography. All purification steps required fewer than 3 days, and the yield of purified 3,4,5-tri-O-caffeoylquinic acid was calculated to exceed 76 mg from 100 g of leaf powder. Its recovery was estimated to be more than 66%, and its purity more than 98%. The aldose reductase inhibitory activities of these derivatives were 3,4,5-tri-O-caffeoylquinic acid > 3,4-di-O-caffeoylquinic acid = 3,5-di-O-caffeoylquinic acid > 4,5-di-O-caffeoylquinic acid > 5-O-caffeoylquinic acid. These results indicate that 3,4,5-tri-O-caffeoylquinic acid is the more bioactive component, and this purification method enables in vivo experiments.
The polyphenol fraction of Actinidia arguta (AP) inhibited α-glucosidase activity in vitro. The oral administration of AP with maltose and starch suppressed postprandial hyperglycemia associated with the intake of the respective sugars by rats. The area under the curve (AUC) of blood glucose in the oral glucose tolerance test (OGTT) of type 2 diabetic KK-Ay mice, fed AP for 6 weeks, significantly decreased when compared with that of the control group. The fraction containing isoquercitrin and hyperoside, which was prepared from AP, showed a stronger inhibitory activity for maltase. The blood glucose levels in OGTT of KK-Ay mice fed isoquercitrin for 4 weeks tended to be lower at 60 min after the administration of glucose. These results suggested that AP has antidiabetic effects, and isoquercitrin, a component of AP, may be useful in preventing type 2 diabetes mellitus. A decrease in the G6Pase activity and increase in the ACO or CPT activities in the liver of KK-Ay mice fed AP or isoquercitrin suggested that the suppression of glu-coneogenesis and the enhancement of β-oxidation of lipids, as well as the inhibition of maltase by AP and isoquercitrin, might also be related to their anti-diabetic effects.
We measured the anti-oxidative and anti-inflammatory activities of hot water extracts prepared from 11 species of mushrooms. Anti-oxidative activity was evaluated using the oxygen radical absorbance capacity method, and anti-inflammatory activity was examined by measuring the inhibition of lysine chloramine formation by hypochlorous acid. Hot water extracts of Grifola gargal (G. gargal) showed the strongest anti-oxidative activity and inhibitory effects on lysine chloramines. Hot water extracts of G. gargal were evaluated by HPLC and divided into 8 fractions. The most active fraction among these 8 fractions was further purified by preparative HPLC. The active component isolated by HPLC was identified as ergothioneine (EGT) using spectral analysis. On HPLC analysis, the EGT content in G. gargal was the highest among the 11 species of mushrooms. We also examined the protective role of EGT by examining the inflammatory response of adipocyte cells induced by tumor necrosis factor-α.
Changes in expression and accumulation of gluten proteins were investigated in developing kernels of 2 wheat cultivars, Norin 61 and Fukusayaka. Expression of 7 gluten subunit genes was detectable 7 days after anthesis (DAA) in both cultivars, while changes in expression patterns of these subunits over time were found to be specific to each cultivar. The accumulation of total proteins and ethanol-soluble proteins was analysed by SDS-PAGE and acidic-PAGE, respectively. The band patterns of total proteins in both cultivars changed markedly between 14 and 21 DAA. Ethanol-soluble proteins, which are mainly gliadin proteins, were detected at 21 DAA in Norin 61 and at 14 DAA in Fukusayaka. We investigated the textural properties of dough prepared from the flour of mature and immature Norin 61. The tension test revealed that dough prepared from immature wheat had higher tensile strength and lower extensibility than that prepared from mature wheat.
Cooked rice bread was made with cooked rice substituted for 0 to 30% of the wheat flour. Eleven rice cultivars were used to clarify the effects of rice properties on specific loaf volume (SLV). The cooked rice bread had higher SLV than the bread without substitution, except for bread made with rice having highamylose content. The maximum specific loaf volume (Max SLV) of cooked rice bread was calculated using SLV loaf volumes. Max SLV was negatively correlated with amylose content and rice hardness, while rice stickiness factors were positively correlated with Max SLV. Because amylose content affects rice hardness and stickiness, amylose content appears to play a key role on SLV. Most of the popular rice cultivars in Japan are sticky and soft, with intermediate amylose content, and yields cooked rice bread with high volume.
We measured the ability of 100 strains of lactic acid bacteria (LAB) isolated from miso to induce Th1-type cytokines (interleukin (IL)-12 and IFN-γ) using mouse Peyer’s patch (PP) cells, and selected Tetragenococcus halophilus MN45 strain (MN45) as the strain with the potential for a strong anti-allergic effect. MN45 cultured in medium containing 15% NaCl for more than 2 days showed the strongest activity of Th1-type cytokine induction among MN45 cultured at various NaCl concentrations and culture times. Next, we analyzed the ability of MN45 to suppress IgE production and the mechanism thereof by neutralizing IL-12 and IFN-γ using PP cells and splenocytes from ovalbumin (OVA)-induced allergic diarrhea model mice. Analysis revealed that MN45 induced IL-12 first, and then IL-12 induced IFN-γ strongly and inhibited IgE production. These results indicate that MN45 may exert an anti-allergic effect.
The effect of cooking in hot air combined with steam and vacuum storage on the quality of turkey meat was studied. The use of steam during cooking decreased cooking losses of turkey meat, and at the same time caused a greater lipid oxidation. The higher rate of SH groups oxidation was found in meat heated with 20, 50 and 90% steam than in meat heated with 0% and 70% steam. Thermal processing caused a decrease in unsaturated fatty acids and an increase in saturated fatty acids content; the smallest changes were demonstrated in meat heated with 20% steam. After thermal processing meat cooked with higher steam (50, 70, 90%) was characterized by better juiciness and tenderness. During storage samples heated in hot air alone and with 20% steam showed lower content of malondialdehyde and better flavour than others samples.
Mead was made from various types of honey and black rice grains in order to brew a red alcoholic beverage with antioxidative activity. Alcoholic beverages made from honey and black rice grains contained around 12 to 13% (v/v) ethanol and greater amounts of phenolic compounds. The color of mead made from various types of honey and black rice grains was similar to that of rosé wine. The concentration of total phenolic compounds ranged from 200 to 300 μg/mL as gallic acid equivalent, while DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity ranged from 800 to 870 μM as Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) equivalent. The inhibitory activity of lipid peroxidation ranged from 2,200 to 2,800 μM as BHT (2,6-di-tert-butyl-p-cresol) equivalent. The antioxidative activity of mead made with unpolished black rice was higher than that of mead made without unpolished black rice. The mead made with Chinese milk vetch honey contained higher amounts of anthocyanin, and was acceptable according to the results of organoleptic testing.
The species of brown seaweeds, Laminaria japonica is commercially cultivated in Japan. Mannitol and uronic acid were the main component of mono sugar produced from the saccharification of L. japonica which hydrolysed with H2SO4 or NH4OH. The mannitol concentration of L. japonica (5 w/v %) hydrolysate using 0.5 v/v % H2SO4 or 1 v/v % NH4OH were 15.84 g/L and 13.87 g/L, respectively. Hydrolysates from both acid and alkali hydrolysis were mixed together for neutralization as well as to obtain higher mannitol concentration of 15.18 g/L. Among the mono sugar in the hydrolysate, Mannitol was the main substrate for the lactic acid fermentation by Lactobacillus rhamnosus. L(+)-Lactic acid with 97.9% of optical purity was successfully produced at the yield of 14.42 g/L (Yp/s = 94.99%).
A homologous gene replacement system was developed for an industrial strain of Aspergillus oryzae KBN630 used in miso production. This system was based on a transformation method involving a bidirectional marker gene, pyrG. To increase the integration of exogenous DNA fragments by homologous recombination, the ku70 gene encoding the Ku70 component of the nonhomologous end-joining machinery was removed from the genome of a pyrG deletion mutant derived from A. oryzae KBN630. The efficiency of homologous integration at the amyR locus was more than 90%.
In order to investigate the effect of pungent components on salt taste sensitivity in humans, sensory evaluation of taste intensity and palatability was performed by adding 0.5 or 1 μM capsaicin (CAP) to a 75 mM NaCl solution. The assessment results suggested that a significant number of subjects experienced stronger salt taste intensity with the CAP-added NaCl solution than that for the NaCl solution alone. A quantitative analysis performed by adding CAP to the NaCl solution revealed an increase in the salt taste intensity. At the same time, the palatability decreased with increasing concentration of CAP. The increase in salt taste intensity after the addition of CAP suggests that addition of pungent components might influence salt sensitivity in humans.
Phycoerythrin from the red alga Porphyra yezoensis has been demonstrated to possess antioxidative activity and is expected to have anti-inflammatory activity. In this study, we examined the effects of phycoerythrin and its pigment moiety, phycoerythrobilin, on the degranulation of mast cells. Phycoerythrin (0.01 mg/mL) and phycoerythrobilin (1 μmol/L) significantly inhibited calcium ionophore (A23187) induced release of β-hexosaminidase from rat basophilic leukemia (RBL-2H3) cells (approximately 50% and 40%, respectively). Phycoerythrobilin significantly suppressed IgE-antigen-stimulated degranulation of RBL-2H3 cells, while phycoerythrin had no effect. A23187-induced degranulation of peritoneal exudate cells (PEC) prepared from rats treated orally with phycoerythrin (4 mg/kg) or phycoerythrobilin (1 μmol/kg) was significantly reduced compared to control PEC. These results suggest that phycoerythrin and phycoerythrobilin exhibit anti-inflammatory activities through the suppression of mast cells degranulation in vivo.