Fermentation Process and Grain Structure of Baked Breads from Frozen Dough Using Freeze-Tolerant Yeasts

The fermentation process for frozen doughs using freeze‐sensitive (Saccharomyces cerevisiae, Kyowa for sweet bread; S. cerevisiae, FC for white bread) and freeze‐tolerant (S. cerevisiae, YF for sweet bread) yeasts was traced by magnetic resonance imaging (MRI). Grain network structures of baked breads were also visualized by MRI. Prefermentation before freezing, punching and remolding, or resheeting and molding treatments increased loaf volume by 10 to 110% for the baked breads using freeze‐tolerant yeast, while these treatments decreased loaf volume by 70% using freeze‐sensitive yeast. The first fermentation before freezing and the second fermentation with punching or resheeting after thawing are useful for obtaining good quality breads from frozen dough using freeze‐tolerant yeast.     

First paralytic shellfish poison (PSP) infestation of bivalves due to toxic dinoflagellate Alexandrium tamiyavanichii, in the southeast coasts of the Seto Inland Sea, Japan

The mussel Mytilus edulis and the cultured ark shell Anadara broughtonii in the southeast coasts of the Seto Inland Sea were contaminated with paralytic shellfish poison (PSP) following the appearance of the dinoflagellate Alexandrium tamiyavanichii in early December 1999. A. tamiyavanichii plankton collected around the Straits of Naruto on December 3, 1999 showed PSP toxicity, of which 83 mol% was accounted for by GTX2, GTX3 and GTX4. Its specific toxicity was 112.5 fmol/cell, and one MU was equivalent to 7,200 cells. Toxicity values at the beginning of toxification were 4.7 MU/g for the ark shell and 7.3 MU/g for the mussel. In the former, the value remained at almost 4 MU/g, resulting in prohibition of marketing for about two months. In the latter, it sharply decreased to less than 4 MU/g. These bivalves collected during the toxification period were dissected into five tissues, mantle, adductor muscle, hepatopancreas, gills and "others", and submitted to high-performance liquid chromatography (HPLC). The cultured ark shell accumulated GTX2, GTX3 and STX as major components and GTX1, GTX4, GTX5, neoSTX, dcSTX and PX1-3 (C1-C3) as minor ones. The amount of GTX3 decreased with time, while STX tended to increase. At the early stage of PSP toxification, toxins were accumulated in the gills and "others", most of which were quickly detoxified. On the other hand, PSP of the toxified mussel consisted of GTX4 as a main component, and GTX1, GTX2, GTX3, GTX5, STX and PX1-2 (C1-C2) as minor ones. Its toxin composition pattern was similar to that of the ingested causative plankton. Its total toxin decreased soon after disappearance of the dinoflagellate. During the decrease of toxicity, PSP tended to be retained in the hepatopancreas, resulting in accumulation of 50 mol% of total toxin.     

Determination of ethychlozate and its degradation product in fruits by HPLC and LC/MS

A method was developed for the analysis of ethychlozate (CIE) and its decomposition compound, 5-chloro-3(1H)-indazolylacetic acid (CIA) in fruits by HPLC and LC/MS. The sample was homogenized with 1 mol/L HC1, and CIE and CIA were extracted with 5 mol/L HCl and acetone. They were extracted from the acetone extract with diethylether-n-hexane (2:1). CIE was hydrolyzed to CIA with methanol-4 mol/L KOH (1:1). The solution was made acidic, and CIA was extracted with diethylether-n-hexane (2:1). The extract was cleaned up on a silica gel column. CIA was determined by HPLC-UV and LC/MS (Scan or SIR). Four fruits were spiked with CIE or CIA at 0.5 microgram/g and analyzed by the proposed method with HPLC. The average recoveries were 77.2-83.2% for CIE and 71.2-89.2% for CIA. The concentrations determined by LC/MS were 10-25% higher than the values by HPLC. The limit of detection (LOD) of CIA standard solution by HPLC corresponds to 0.015 microgram/g of CIE in the sample. In the same way, the LOD of CIA by LC/MS (SIR) corresponds to 0.009 microgram/g of CIE in the sample.     

Comparison of DNA sequencing analysis with phenotyping test for identification of yeasts isolated from foods

The identification of 20 strains of yeasts isolated from foods by means of DNA sequence analysis with two kinds of universal primers for the rDNA region was examined, and the results were compared with those of the conventional phenotyping test using API 20C AUX. In the analysis of the 26S region, all 20 yeast strains tested were identified at the species level. In the ITS1 region, 16 strains were also classified at the species level. In addition, all results of DNA sequence analysis were consistent with those of the phenotyping test at the genus level. Furthermore, DNA sequence analysis was able to identify causative yeasts observed in two suspect foods, though phenotyping tests alone failed to identify them.     

Effect of static pressure on intracellular pH of adhesive Chinese hamster ovary cells

The effect of static pressure on the intracellular pH of the Chinese hamster ovary (CHO) cell line DR1000L4N was investigated. In cultivation of CHO cells at 0.9 MPa, two distinct populations were observed in the histogram of a flow cytometer, while single population was observed in cultivation at 0.1 MPa. The intracellular pH of the major population at 0.9 MPa was markedly lower than that of the single population at 0.1 MPa.     

绿茶饮料浓缩物缓解体力疲劳实验研究

目的:探讨绿茶饮料浓缩物缓解小鼠体力疲劳的作用。方法:240只清洁级雄性昆明小白鼠随机分为4组,分别以经口灌胃方式给予蒸馏水(对照组)、不同剂量绿茶饮料浓缩物[133mg/(kg·bw),665mg/(kg·bw),1995mg/(kg·bw)],每日1次,连续45d,进行负重游泳实验,测定血乳酸、血清尿素及肝糖原含量。结果:与对照组比,低、中剂量能够增加小鼠负重游泳时间(P<0.01);低剂量组可降低游泳后即刻的血乳酸水平(P<0.05),各剂量组均能降低游泳后20min的血乳酸水平(P<0.05);中剂量组能够增加小鼠肝糖原储备(P<0.05);各剂量组血清尿素水平没有明显变化(P>0.05)。结论:绿茶饮料浓缩物具有缓解小鼠体力疲劳的作用,以中剂量作用最强。     

The protein encoded by cancer/testis gene D40/AF15q14 is localized in spermatocytes, acrosomes of spermatids and ejaculated spermatozoa

We have previously identified and cloned a human gene, D40, that is preferentially expressed in testis among normal organs, while it is widely expressed in various human tumor cell lines and primary tumors derived from different organs. In this report, we have examined the expression and localization of this protein in human testis with an antibody specific to D40 protein. In Western analyses, the anti-D40 antibody recognized a major band with a molecular mass of 300 kDa and a minor band of 250 kDa. These bands were not observed in the testis lysates from patients with Sertoli-cell-only syndrome and with Kleinfelter syndrome, who lack germ cells of the testis, indicating that D40 protein is expressed in the germ cells of normal testis. Immunohistochemical studies have revealed that D40 protein is highly expressed in spermatocytes and in the pre-acrosome of round spermatids. In the acrosome, D40 protein expression is observed not inside but outside the acrosome membrane. This is consistent with the finding that the amino-acid sequence at the amino terminal of the D40 protein lacks a hydrophobic signal peptide that is required for proteins to translocate to the membrane. Expression of D40 protein is observed in the acrosome of ejaculated spermatozoa as well, although the level is low compared with that in the pre-acrosome of spermatids. These results suggest that D40 protein plays important roles in spermatogenesis, especially in the formation and maintenance of the acrosome.     

Environmental remediation by an integrated microwave/UV illumination technique. 8. Fate of carboxylic acids, aldehydes, alkoxycarbonyl and phenolic substrates in a microwave radiation field in the presence of TiO2 particles under UV irradiation

Thermal and nonthermal effects originating when a system is subjected to a microwave radiation field in the TiO2-photocatalyzed transformation of model substances containing various functional groups (e.g., benzoic acid, phthalic acid, o-formylbenzoic acid, phthalaldehyde, succinic acid, dimethyl phthalate, diethyl phthalate, and phenol) have been examined under simultaneous irradiation by ultraviolet (UV) and microwave (MW) radiations. Characteristics of the microwave effects and the fate of each substrate during the microwave-assisted photocatalytic process were monitored by UV absorption spectroscopy, HPLC methods, total organic carbon assays, and identification of intermediates using electrospray mass spectral techniques. Microwave thermal and nonthermal effects were delineated by comparing results from MW-generated internal heat versus conventional external heating, and at constant ambient temperature under a microwave field. Factors involved in the nonthermal component of the microwave radiation were inferred for the initial adsorption of the substrate and its subsequent degradation occurring on the surface of TiO2 particles. Microwave effects bear on the mechanism through which a model substrate undergoes oxidative degradation. A characteristic feature of these effects was briefly examined by considering the behavior of polar (dipole moments) substrates in a microwave radiation field.     

Microencapsulation of bioactive compounds from mulberry (Morus alba L.) leaf extracts by protein–polysaccharide interactions

Mulberry leaf extracts were generated using four concentrations of ethanol (50%, 60%, 70%, and 95% v/v). A 60% ethanolic mulberry leaf extract (60E) yielded a high total phenolic content (TPC) and antioxidant activity using 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging and a ferric reducing antioxidant power (FRAP) assay. Coating materials were derived using a combination of soy protein isolates (SPI) and low methoxyl (LM) pectin in a 1:1 ratio. The effect of various parameters on microencapsulation, such as pH (3.5, 4.0, and 4.5) and the concentration of coating materials (2.5, 5.0 and 7.5% w/v), was studied. Microcapsules produced using 60E as a core material at pH 4.0 with 7.5% of coating material showed a high encapsulation yield, encapsulation efficiency, TPC and antioxidant activity.