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101.
《Bioscience, biotechnology, and biochemistry》2013,77(8):1453-1462
(-)-Podorhizol (1) was stereoselectively synthesized by erythro preferential aldol condensation of 3,4,5-trimethoxy- benzaldehyde with potassium enolate from (+)-(R)-3- (3,4-methylenedioxybenzyl)-4-butanolide (2) (erythro:threo=85:15). Erythro selectivity was observed in the aldol condensation of many alkoxybenzaldehydes with potassium enolate from (+)-γ-butyrolactone 2. However, benzaldehydes having methoxy groups at both the 2 and 6 positions gave threo selectivity in the aldol condensation with potassium enolate from (+)-γ-butyrolactone 2. 相似文献
102.
《Bioscience, biotechnology, and biochemistry》2013,77(12):3265-3272
Marine yeasts were collected from coastal and deep sea areas in the Pacific Ocean and the Sea of Japan around central and northern Japan to prepare a novel type of natural seasoning. It was found that one of the marine yeasts collected from the Pacific Ocean off Hachinohe showed a high concentration of γ-aminobutyric acid (GABA) in its extract, about 7–10 times higher than those of commercially available bread yeast and other marine yeasts. The marine yeast isolated and named Hachinohe No. 6 catalyzed the reaction from monosodium glutamate to GABA only in the presence of glucose. Subsequently, several marine yeasts belonging to the genera Pichia and Candida were found to have such catalytic activities, but not those belonging to the genus Saccharomyces. Isolate Hachinohe No. 6 was found to have the highest catalytic activity among the yeasts examined in this study. 相似文献
103.
Kohei Oda Takanori Imanishi Yoshito Yamane Yoshie Ueno Yoshiharu Mori 《Bioscience, biotechnology, and biochemistry》2013,77(5):882-890
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business. 相似文献
104.
Hajime Yoshida Yoshitake Tanaka Kiyoshi Nakayama 《Bioscience, biotechnology, and biochemistry》2013,77(9):2121-2126
Six strains of bacteria belonging to Vibrio and Pseudomonas were selected as good producers of L-DOPA from L-tyrosine out of various bacteria. The condition for the formation of L-DOPA by Vibrio tyrosinaticus ATCC 19378 was examined and the following results were obtained. (1) Intermittent addition of L-tyrosine in small portions gave higher titer of L-DOPA than single addition of L-tyrosine. (2) Higher amount of L-DOPA was produced in stationary phase of growth than in logarithmic phase. (3) Addition of antioxidant, chelating agent or reductant such as L-ascorbic acid, araboascorbic acid, hydrazine, citric acid and 5-ketofructose increased the amount of L-DOPA formed. (4) L-Tyrosine derivatives such as N-acetyl-L-tyrosine amide, N-acetyl-L-tyrosine, L-tyrosine amide, L-tyrosine methyl ester and L-tyrosine benzyl ester were converted to the corresponding L-DOPA derivatives.In the selected condition about 4 mg/ml of L-DOPA was produced from 4.3 mg/ml of L-tyrosine. 相似文献
105.
《Bioscience, biotechnology, and biochemistry》2013,77(5):750-752
A process was developed to produce a characteristic milk gel. Raw and market milk samples were freeze-concentrated using bacterial ice nuclei. The concentrates were kept at 5°C and compressed at 300–600 MPa for 5 min. The combination of the freeze concentration and the pressurization gave a milk gel without adding any gelling agents. The addition of sugar at 10% to the concentrated milk improved its gel strength and viscoelasticity. The gel was characterized by a phase transition at about 62–75°C. 相似文献
106.
Ji-Yeon Lee 《Bioscience, biotechnology, and biochemistry》2013,77(10):1656-1661
A gene encoding glutamate decarboxylase A (GadA) from Lactobacillus brevis BH2 was expressed in a His-tagged form in Escherichia coli cells, and recombinant protein exists as a homodimer consisting of identical subunits of 53?kDa. GadA was absolutely dependent on the ammonium sulfate concentration for catalytic activity and secondary structure formation. GadA was immobilized on the metal affinity resin with an immobilization yield of 95.8%. The pH optima of the immobilized enzyme were identical with those of the free enzyme. However, the optimum temperature for immobilized enzyme was 5?°C higher than that for the free enzyme. The immobilized GadA retained its relative activity of 41% after 30 reuses of reaction within 30?days and exhibited a half-life of 19 cycles within 19?days. A packed-bed bioreactor with immobilized GadA showed a maximum yield of 97.8% GABA from 50?mM l-glutamate in a flow-through system under conditions of pH 4.0 and 55?°C. 相似文献
107.
Qifu Yang Miku Miyagawa Xiaoyang Liu Beiwei Zhu Shintaro Munemasa Toshiyuki Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(12):2158-2167
ABSTRACTMethyl-β-cyclodextrin (MβCD) is an effective agent for the removal of plasma membrane cholesterol. In this study, we investigated the modulating effects of MβCD on the antiproliferation induced by benzyl isothiocyanate (BITC), an ITC compound mainly derived from papaya seeds. We confirmed that MβCD dose-dependently increased the cholesterol level in the medium, possibly through its removal from the plasma membrane of human colorectal cancer cells. The pretreatment with a non-toxic concentration (2.5 mM) of MβCD significantly enhanced the BITC-induced cytotoxicity and apoptosis induction, which was counteracted by the cholesterol supplementation. Although BITC activated the phosphoinositide 3-kinase (PI3K)/Akt pathway, MβCD dose-dependently inhibited the phosphorylation level of Akt. On the contrary, the treatment of MβCD enhanced the phosphorylation of mitogen activated protein kinases, but did not potentiate their BITC-induced phosphorylation. These results suggested that MβCD might potentiate the BITC-induced anti-cancer by cholesterol depletion and thus inhibition of the PI3K/Akt-dependent survival pathway.Abbreviations: CDs: cyclodextrins; MβCD: methyl-β-cyclodextrin; ITCs: isothiocyanates; BITC: benzyl isothiocyanate; PI3K: phosphoinositide 3-kinase; PDK1: phosphoinositide-dependent kinase-1; MAPK: mitogen activated protein kinase; ERK1/2: extracellular signal-regulated kinase1/2; JNK: c-Jun N-terminal kinase; PI: propidium iodide; FBS: fatal bovine serum; TLC: thin-layer chromatography; PBS(-): phosphate-buffered saline without calcium and magnesium; MEK: MAPK/ERK kinase; PIP2: phosphatidylinositol-4,5-bisphosphate; PIP3: phosphatidylinositol-3,4,5-trisphosphate 相似文献
108.
Methods including spectroscopy, electronic chemistry and thermodynamics were used to study the inclusion effect between γ-cyclodextrin (CD) and vitamin K3(K3), as well as the interaction mode between herring-sperm DNA (hsDNA) and γ-CD-K3 inclusion complex. The results from ultraviolet spectroscopic method indicated that VK3 and γ-CD formed 1:1 inclusion complex, with the inclusion constant Kf = 1.02 × 104 L/mol, which is based on Benesi–Hildebrand's viewpoint. The outcomes from the probe method and Scatchard methods suggested that the interaction mode between γ-CD-K3 and DNA was a mixture mode, which included intercalation and electrostatic binding effects. The binding constants were K θ25°C = 2.16 × 104 L/mol, and Kθ37°C = 1.06 × 104 L/mol. The thermodynamic functions of the interaction between γ-CD-K3 and DNA were ΔrHmθ = ?2.74 × 104 J/mol, ΔrSmθ = 174.74 J·mol?1K?1, therefore, both ΔrHmθ (enthalpy) and ΔrSmθ (entropy) worked as driven forces in this action. 相似文献
109.
Yasuo Oowatari Tetsuro Ogawa Takuya Katsube Kiyohisa Iinuma Hisae Yoshitomi Ming Gao 《Bioscience, biotechnology, and biochemistry》2016,80(8):1594-1601
Hypertrophy of adipocytes in obese adipose tissues causes metabolic abnormality by adipocytokine dysregulation, which promotes type 2 diabetes mellitus, hypertension, and dyslipidemia. We investigated the effects of wasabi (Wasabia japonica Matsum) leaf extracts on metabolic abnormalities in SHRSP.Z-Leprfa/IzmDmcr rats (SHRSP/ZF), which are a model of metabolic syndrome. Male SHRSP/ZF rats aged 7 weeks were divided into two groups: control and wasabi leaf extract (WLE) groups, which received water or oral treatment with 4 g/kg/day WLE for 6 weeks. WLE improved the body weight gain and high blood pressure in SHRSP/ZF rats, and the plasma triglyceride levels were significantly lower in the WLE group. Adipocyte hypertrophy was markedly prevented in adipose tissue. The expression of PPARγ and subsequent downstream genes was suppressed in the WLE group adipose tissues. Our data suggest that WLE inhibits adipose hypertrophy by suppressing PPARγ expression in adipose tissue and stimulating the AMPK activity by increased adiponectin. 相似文献
110.