In screening of selective inhibitors of eukaryotic DNA polymerases (pols) for 15 years, more than 100 inhibitors have been discovered from natural and chemical sources. Some compounds selectively inhibit the activities of mammalian pols, and in particular, dehydroaltenusin and curcumin derivatives, such as monoacetyl-curcumin, were found to be specific inhibitors of pol α and pol λ, respectively. Dehydroaltenusin was isolated from a fungus (Alternaria tennuis), and this compound inhibited cell proliferation of human cancer cell lines by arresting the cells at the S-phase, and was effective in suppressing the growth on nude mice of solid tumors of human cervical cancer cell line HeLa. Curcumin derivatives had anti-12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammatory activity with the same tendency as pol λ inhibitory activity. These compounds might be useful not only as “molecular probes” for pol research, but also as biomedical and chemotherapeutic drugs for anti-cancer or anti-inflammation.

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We determined the sulfation patterns and the amount of chondroitin sulfate in several tissues of the diamond squid, Thysanoteuthis rhombus. Every tissue contained the highly-sulfated E type of chondroitin. The arms, skin, and fin had non-sulfated chondroitin as the homogenous polymer. The skin and fin possessed larger amounts of chondroitin sulfate per unit of weight than the other tissues.

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Procyanidin oligomers with different degrees of polymerization (up to nonamers) were efficiently purified from the bark of Jatoba (Hymenaea courbaril) by using a recently developed chromatographic separation method. Purification relied on a hydrogen bonding interaction between phenolic hydroxyl groups of the procyanidins and polyethylene glycol (PEG)-coated resin in a packed column. The individual procyanidins were identified by using electrospray ionization mass spectrometry (ESI-MS) and verified by a thiolytic degradation analysis. Our results demonstrate that Jatoba bark contained a large amount of procyanidins from monomer to nonamers or higher polymers composed of only B-type linked units (flavan-3-ol units linked through C-4 to C-8 (or C-6)) of epicatechin (EC) without gallate esters.

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DIMBOA [2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one] is a benzoxazinoid (Bx), part of the chemical defense system of graminaceous plants such as maize, wheat, and rye. When Bombyx mori larvae were fed artificial diets containing DIMBOA, they died in three days. In contrast, Mythimna separata larvae, a serious pest of rice, maize, sorghum, wheat etc., grew well on the same diets. Three kinds of glucosides [1-(2-hydroxy-4-methoxyphenylamino)-1-deoxy-β-glucopyranoside-1,2-carbamate (methoxy glucoside carbamate), 2-O-β-glucopyranosyl-4-hydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA-2-O-Glc), and 2-O-β-glucopyranosyl-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (HMBOA-2-O-Glc)] were identified by LC-MS and NMR analyses from the frass of M. separata that had been fed on a DIMBOA-containing diet. Furthermore, the incubation of DIMBOA with a midgut tissue suspension of M. separata in the presence of UDP-D-glucose generated DIMBOA-2-O-Glc. These findings strongly suggest that glucosylation by UDP-glucosyltransferase(s) was important for detoxification to circumvent the defenses of host plants against M. separata larvae.

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In our searching program for novel sorbicillin related compounds, three novel compounds, spirosorbicillinols A (1), B (2), and C (3), were isolated from the fermentation broth of the USF-4860 strain isolated from a soil sample. The planar structures of compounds 1–3 were determined from spectroscopic evidence and degradation reaction, and that of 1 was the same as that of 2. The relative stereochemistries of compounds 1–3 were determined by ¹H-¹H coupling constants, the elucidation of HMBC and NOESY spectra in detail. 1 and 2 were stereoisomers at C8 position, each other. We propose that compounds 1 and 2 were formed by exo and endo intermolecular Diels-Alder reaction between sorbicillinol as a diene and scytolide (proposed precursor-1) as a dienophile, respectively. Similarly, we propose that compound 3 was formed by an endo intermolecular Diels-Alder reaction between sorbicillinol and proposed precursor-2.

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Leaf extracts of five medicinal ferns, Acrostichum aureum L. (Pteridaceae), Asplenium nidus L. (Aspleniaceae), Blechnum orientale L. (Blechnaceae), Cibotium barometz (L.) J. Sm. (Cyatheaceae) and Dicranopteris linearis (Burm.) underwood var. linearis (Gleicheniaceae), were investigated for their total phenolic content (TPC), and antioxidative, tyrosinase inhibiting and antibacterial activities. The antioxidative activity was measured by assays for radical scavenging against 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric ion reducing power (FRP), beta-carotene bleaching (BCB) and ferrous ion chelating (FIC). The results revealed B. orientale to possess the highest amount of total polyphenols and strongest potential as a natural antioxidative, tyrosinase inhibiting and antibacterial agent as demonstrated by its strong activities in all related bioassays. The other ferns with antioxidative potential were C. barometz and D. linearis. Except for A. aureum, all ferns showed antibacterial activity which may justify their usage in traditional medicines.

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Germination stimulants for root parasitic plants produced by flax (Linum usitatissimum L.) were purified and characterized. The root exudate of flax contained at least 8 active fractions, and liquid chromatography-tandem mass spectrometry (LC–MS/MS) and gas chromatography mass spectrometry (GC–MS) analyses suggested that there were 6 strigolactones. Two of them were identified as orobanchol and orobanchyl acetate by comparing NMR and GC–MS and LC–MS/MS data with those of synthetic standards. One of the two novel strigolactones was purified and determined as 7-oxoorobanchyl acetate [((3aS,4S,8bS,E)-8,8-dimethyl-3-(((R)-4-methyl-5-oxo-2,5-dihydrofuran-2-yloxy)methylene)-2,7-dioxo-3,3a,4,5,6,7,8,8b-octahydro-2H-indeno[1,2-b]furan-4-yl acetate) by 1D and 2D NMR spectroscopic, and ESI– and EI–MS spectrometric analyses. The other one was also purified and identified as 7-oxoorobanchol. The remaining two compounds could not been characterized due to their scarcity.

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The Friedel-Crafts reaction with 3-(3-methoxyphenyl)-3-(trifluoromethyl)-3H-diazirine and optically active N-TFA-Asp(Cl)-OMe in triflic acid afforded homophenylalanine derivatives without any loss of the optical purity.

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Arabidopsis seedlings increased extracellular ATP (exATP) concentrations transiently in extracellular matrix (ECM) under hypertonic stresses. The increased transcription levels of two apyrase genes, AtAPY1 and AtAPY2, in accordance with exATP accumulation, suggests active regulation of exATP concentration. Arabidopsis seedlings subjected to hypertonic stresses survived after incubation with β,γ-methyleneadenosine-5′-triphosphate, which usually causes cell death through competitive exclusion of ATP. This confirms that the enhanced viability was due to accumulated exATP. The increased concentration of hydrogen peroxide through NADPH oxidase expression suggests the possible importance of exATP in stress response under hypertonic stresses. The mRNA levels of exATP inducible genes (AtMAPK3, AtACS6, and AtERF4) and the reactive oxygen species inducible gene (AtPAL1) were increased by hypertonic stresses. We suggest that exATP accumulation plays a role as a regulatory mechanism in the hypertonic stress response in Arabidopsis seedlings.

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Linoleic acid (LA) improves insulin resistance and prevents diabetes. To investigate whether linoleic acid could protect against streptozotocin (STZ)-induced cell death, rat RIN-m5F cells were exposed to STZ. SL and SO groups consisted of cells treated with STZ and then LA or oleic acid (OA) respectively. STZ treatment decreased the mitochondrial membrane potential in the STZ, SO, and SL groups. Cells of the SL group had more intact mitochondria. Increased mRNA expression of mitochondrial DNA (mtDNA) and nuclear DNA (nDNA), as well as of the mitochondrial biogenesis regulators peroxisome proliferator activated receptor γ coactivator-1α (PGC-1α), and mitochondrial transcription factor A (Tfam), were found in the LA group. The insulin content was significantly decreased in all three groups. These results suggest that the effects of LA on cell viability after STZ damage occur through maintenance of mitochondrial structure and increased mitochondrial biogenesis.

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Human cytomegalovirus is a common human pathogen that can cause life-threatening disease under certain conditions. During infection of host cells, the virus expresses regulatory proteins such as IE72 and IE86 that are important for viral propagation. IE86 plays a critical role in the modulation of viral replication as well as host cell cycle control and apoptosis. In this study, a Tet-On system was used to quantify the effect of IE86 on apoptosis and p53 expression. Our results indicate that IE86 inhibits tumor necrosis factor (TNF)-α induced apoptosis and that the anti-apoptotic activity of this viral protein correlates with its expression levels. In addition, IE86 did not alter the mRNA level of p53. The system developed should provide a method for functional analysis of human cytomegalovirus (HCMV) IE86 protein.

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Carbidopa and benserazide have been described as inhibitors of dopa decarboxylase and both have been used in the treatment of Parkinson’s disease. Because of their chemical structure as polyphenols, these compounds can behave as substrates of tyrosinase and peroxidase. We demonstrate that these enzymes oxidize both substrates. Since o-quinones are unstable, a chronometric method for enzymatic initial rate determinations was used based on measurements of the lag period in the presence of micromolar concentrations of ascorbic acid to kinetically characterize these substrates. In the case of tyrosinase, the values of the Michaelis constant for both substrates were greater than those described for dopa, although the catalytic constants were lower, probably due to the greater size of the substitute group in carbon 1. As regards peroxidase, the saturation of the enzyme by both substrates is possible, however this effect does not occur with the isomers of dopa. The distance of the charges from the benzene ring may enable the ring to approach the iron of the active site and, therefore, act.

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We have reported that heat shock protein 27 (HSP27) and annexin II are involved in the protection of human cells against UVC-induced cell death. In this study we tried to confirm the combined roles of HSP27 and annexin II in cell death after UVC irradiation. In RSa cells with sensitivity to UVC, expression of annexin II decreased after UVC irradiation, but not in AP^r-1 cells with increased resistance to UVC. HSP27 siRNA-transfected AP^r-1 cells were sensitized to UVC lethality and showed decreased annexin II expression after UVC irradiation. In contrast, transfection of RSa cells with HSP27 cDNA increased their resistance to UVC lethality and caused increased annexin II expression. Furthermore, over-production of annexin II in RSa cells resulted in increased resistance to UVC lethality. This study indicates the involvement of cellular HSP27 expression in the UVC susceptibility of human cells, which occurs in association with regulation of annexin II expression.

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The moc3 gene was screened out as an inducer of sexual differentiation in fission yeast Schizosaccharomyces pombe. We isolated a novel gene, named ers2, encoding mitochondrial glutamyl tRNA synthetase (mGluRS) as a Moc3 interacting element by the yeast two-hybrid system. Cytoplasmic glutamyl tRNA synthetase (cGluRS) also interacted with Moc3 in a yeast two-hybrid system. Disruption of ers1 (cGluRS) and of ers2 (mGluRS) indicated that these genes are both essential for the cell growth of S. pombe. We found that ers2 severely affected cell growth and decreased viability, but induced sexual differentiation of S. pombe when it was over-expressed. Over-expression of ers1 also stimulated sexual differentiation in S. pombe. These observations led us to test the effects of various amino acids on sexual differentiation. We found that glutamic acid, as well as other specific amino acids, such as tryptophan, methionine, and threonine, efficiently induced sexual differentiation in S. pombe. Our findings suggest a new regulatory mechanism where GluRSs and glutamic acid are involved in sexual differentiation in S. pombe.

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Saccharomyces cerevisiae strain TIY20, which produces a mammalian high-mannose type N-glycan, exhibits a severe growth defect due to disruption of yeast-specific outer chain mannosyltransferases. We have isolated a more fit strain, YAB103, from TIY20 by the use of a novel mutagenesis technique based on the disparity theory of evolution. To determine why YAB103 lacked the growth defect and the hygromycin B sensitivity of its parent, TIY20, gene expression profiles of YAB103 and TIY20 were analyzed using DNA microarrays. Expression of genes that encode enzymes in the gluconeogenesis pathway and glyoxylate cycle, which produce glucose 6-phophate and its derivatives, was up-regulated in YAB103. Up-regulation of these genes suppressed the drug sensitivity of the TIY20 strain. Furthermore, we found that YAB103 had a thicker cell-wall due to an increase in glucan content. To our knowledge, this is first report linking N-glycosylation to gluconeogenesis and the glyoxylate cycle.

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The methylotrophic yeast Pichia pastoris can grow on methanol as sole source of carbon and energy. The first reaction in yeast methanol metabolism, catalyzed by an abundant peroxisomal enzyme, alcohol oxidase, generates high levels of H₂O₂, but the oxidative stress response during methanol metabolism has not been elucidated. In this study, we isolated the Yap1 homolog of P. pastoris (PpYap1) and analyzed the properties of a PpYAP1-disruption strain. The PpYap1 transcription factor is activated after exposure to various reactive agents, and therefore functions as a regulator of the redox system in P. pastoris. We have also identified PpGPX1, the unique glutathione peroxidase-encoding gene in P. pastoris whose expression is induced by PpYap1. PpGpx1, but not the ScTsa1 or SpTpx1 homolog PpTsa1, functions as a H₂O₂ sensor and activates PpYap1. This study is the first demonstration of a yeast Yap1 family protein activated during conventional metabolism.

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Six Bifidobacterium adolescentis strains, JCM1275, JCM1251, JCM7044, JCM7045, JCM7046, and 9-124, were analyzed using a tiling array designed according to the full genome sequence of ATCC15703. The results demonstrated deletion clusters along with single-gene mutations and deletions. Most deletions concerned genes involved in polysaccharide and cell-surface biogenesis. A dendrogram illustrating the deletions and mutations is presented and the evolution of B. adolescentis is discussed.

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The cbnA gene encoding chlorocatechol dioxygenase from the soil bacterium Ralstonia eutropha NH9 under the control of a modified cauliflower mosaic virus 35S promoter was introduced into a hybrid poplar (Populus tremula × P. tremuloides). Integration of the cbnA gene in transgenic poplar was confirmed by PCR and genomic Southern blot analysis. Expression of the cbnA gene was analyzed by Western blot analysis. Transgenic poplar calli efficiently converted 3-chlorocatechol to 2-chloro-cis,cis-muconate.

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Recombinants, Cel6 from Coprinopsis cinerea (CcCel6)A, -B, and -C, were expressed by Escherichia coli. These enzymes produced cellobiose from phosphoric acid-swollen cellulose. When Avicel was used as the substrate, CcCel6A showed higher activity toward the substrate than CcCel6B or -C. In reaction with carboxymethylcellulose, CcCel6B and -C hydrolyzed the substrate, whereas CcCel6A failed to react.

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Asaccharobacter celatus AHU1763 is a Gram-positive, obligate anaerobic, non-spore forming, rod-shaped bacteria that was successfully isolated from rat cecal content. Daizein was converted to equol via dihydrodaidzein by this bacterium. A crude enzyme that converted daidzein to dihydrodaidzein was detected mainly in the culture supernatant. The ability of this enzyme dropped after the culture supernatant was exposed to a normal atmospheric environment for even 5 min. Furthermore, the enzyme responsible for changing dihydrodaidzein to equol was detected mainly in the cell debris, which required anaerobic conditions for its activity.

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The full-length cDNA sequence of a new pheromone-binding protein (AscrPBP2) was determined from a geometrid moth, Ascotis selenaria cretacea, which secreted a Type II sex pheromone, and an antiserum against its recombinant protein overexpressed in Escherichia coli was prepared. In addition to this antiserum against AscrPBP2, antibodies against AscrPBP1 and general odorant-binding proteins of Bombyx mori were used in Western blotting experiments to analyze the proteins in the antennae of several lepidopteran species secreting Type II sex pheromone components.

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Flagellin glycosylation was identified in Bacillus sp. PS3 and Geobacillus stearothermophilus. In vivo complementation showed that these flagellin genes did not restore the motility of a Bacillus subtilis flagellin mutant, whereas the genes encoding non-glycosylated flagellin from Geobacillus kaustophilus and Bacillus sp. Kps3 restored motility. Moreover, four types of flagellins expressed in B. subtilis were not glycosylated. We speculate that glycosylation is required for flagellar filament assembly of these bacilli.

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Insulin-like growth factor-I (IGF-I) reduces arterial blood pressure. Since administration of capsaicin and isoflavone increases serum levels of IGF-I by sensory neuron stimulation in subjects with alopecia, it is possible that administration of capsaicin and isoflavone reduces arterial blood pressure in patients with hypertension. Systolic and diastolic blood pressure (BP) and serum levels of IGF-I were determined before and at 1, 3, and 5 months after administration of capsaicin and isoflavone in 42 volunteers with alopecia, 29 normotensive and 13 hypertensive volunteers. Neither systolic nor diastolic BP changed in the normotensive volunteers after combined administration of capsaicin and isoflavone. In contrast, systolic and diastolic BP was significantly reduced in hypertensive volunteers after administration of capsaicin and isoflavone. Serum levels of IGF-I significantly increased in both normotensive and hypertensive volunteers after administration of capsaicin and isoflavone. These observations suggest that administration of capsaicin and isoflavone might reduce BP in hypertensive, but not in normotensive subjects, probably by increasing serum levels of IGF-I.

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We assessed the damage to onion tissue due to freeze-thawing as the water permeability determined by using PFG-NMR and light microscopy. The water diffusion in fresh onion tissue was restricted due to cellular barriers, and the estimated water permeability was 6.99×10⁻⁶m/s. The water diffusion became considerably less restricted after freeze-thawing; the convergent value for the restricted diffusion coefficient increased and the water permeability significantly increased to 2.85×10⁻⁵ m/s. While NMR could detect a distinct change in the diffusion behavior of water molecules in freeze-thawed tissue, light microscopy revealed no significant tissue damage. These results suggest that freeze-thawing damaged the vegetable tissues primarily through destruction of the cell membrane rather than the cell wall.

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We examined the effects of white wheat bread powder (BP) and white wheat bread powder containing sugar beet fiber (BBP) on serum cholesterol. The total cholesterol (−11%, −16%), HDL-cholesterol (−12%, −11%), non-HDL-cholesterol (−9%, −18%) and triacylglycerol (−44%, −58%) concentrations in the BP and BBP groups, respectively, were significantly different from those in the control group. The fecal excretion of neutral sterols in the BP and BBP groups and of acidic sterols in the BBP group was significantly higher than that in the control group. The hepatic cholesterol 7α-hydroxylase (CYP7A1) mRNA level in the BP and BBP groups was significantly higher than that in the control group. The cecal total short-chain fatty acid concentrations in the BBP group were significantly higher than those in the control group. These results indicate that the observed changes in serum lipid levels in the BP and BBP groups were due to the increased fecal lipid and CYP7A1 mRNA levels.

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A multi-enzymatic system from Penicillium funiculosum displayed α-L-arabinofuranosidase, endo-1,4-β-D-xylanase, β-D-xylosidase and endo-1,3-1,4-β-D-glucanase activities at high levels over a wide acidic pH range of 2.0 to 5.5. Moreover, the pH stability was particularly extended over the wide range of pH of 2.0 to 8.0 with endo-1,3-1,4-β-D-glucanase and endo-1,4-β-D-xylanase; however, α-L-arabinofuranosidase and β-D-xylosidase exhibited higher stability in the pH range of 2.0 to 5.5. The results indicate that the optimal temperature of α-L-arabinofuranosidase (65 °C) and β-D-xylosidase (70 °C) as well as their thermal stability were higher than those of endo-1,3-1,4-β-D-glucanase (60 °C) and endo-1,4-β-D-xylanase (50 °C). Although V_maxapp of β-D-xylosidase and endo-1,4-β-D-xylanase was higher than that of α-L-arabinofuranosidase and endo-1,3-1,4-β-D-glucanase, respectively, their catalytic efficiency was lower. High levels of ferulolyl esterase, α-D-galactosidase, β-D-mannosidase and endo-1,4-β-D-mannanase activities were also detected in the multi-enzymatic system. The overall features of the multi-enzymatic system from P. funiculosum reveal its potential for degrading and modifying plant cell walls from a variety of food and feedstuffs.

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Lysophosphatidic acid (LPA) is a lipid mediator that plays a role in the process of wound healing in animal tissues, including the digestive tract. We determined LPA in several foodstuffs, and found that cabbage leaves were the richest source of LPA. We also found that, at 22 and 195 nmol/g (wet weight), LPA and phosphatidic acid (PA) were respectively formed during mastication of raw cabbage leaves and that the resulting PA was converted to LPA by pancreatic phospholipase A₂. The lipid extract obtained from ground cabbage leaves promoted the proliferation of Swiss 3T3 fibroblasts and the motility of HGC-27 cells, stomach-derived epithelial-like cells, at physiologically relevant concentrations. These activities of cabbage lipids were inhibited by Ki16425, an LPA-receptor antagonist. LPA formed during the digestion of cabbage leaves may be one of the components in the beneficial effect of ingested cabbage on a damaged digestive tract.

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The antibacterial activity of recombinant human lactoferrin from rice (rhLF) compared with that of human milk lactoferrin (hLF) was evaluated against Escherichia coli O157:H7, Salmonella Enteritidis and Listeria monocytogenes. The hydrolysates of rhLF and hLF were found to be more active than native proteins against E. coli O157:H7, and their activity was independent of their iron saturation. The effect of different heat treatments on the antibacterial activity of apo-rhLF was studied and compared with hLF. We observed that an HTST pasteurization treatment did not affect the antimicrobial activity of lactoferrin against the pathogens studied. Furthermore, the activity of apo-rhLF and hLF against E. coli O157:H7 and L. monocytogenes in UHT milk and whey was assayed, finding a decrease in the number of bacteria, although lower than that observed in a broth medium. This study shows the similar antibacterial activity of rhLF and hLF which is important in order to consider the addition of rhLF as a supplement in special products.

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Pine bark extract (PBE) mainly contains proanthocyanidin in oligomers. It has many physiological effects, including antioxidant, anti-inflammatory, and so on. In this study, we investigated whether PBE has an anti-atherogenic effect on apoE-deficient mice. Male and female mice were fed a diet based on an AIN-76 formula (control diet), and that diet supplemented with 2% PBE (the PBF diet). The PBE diet, compared with the control diet, resulted in lowering the body weight gain and the adipose tissue weight in both male and female mice. The lesion area of the valve and the levels of serum and liver cholesterol in the male mice decreased on the PBE diet. The PBE diet had no significant effect on the levels of urinary isoprostanes or serum thiobarbituric acid reactive substances. These results indicate that dietary PBE can have beneficial effects on atherosclerosis development in male apoE-deficient mice by lowering the serum cholesterol level.

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Extracts prepared by culturing ten filamentous fungi from Aspergillus and Eurotium species isolated from dried bonito (katsuobushi) were examined for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The extracts prepared by culturing E. herbariorum NE-1 and NE-4, which are used in the molding process for the manufacture of karebushi (a kind of katsuobushi), were shown to have higher activity than the others. Five antioxidants were isolated from the extracts and identified as isodihydroauroglaucin (IDAG), auroglaucin (AG), dihydroauroglaucin (DAG), tetrahydroauroglaucin (TAG), and flavoglaucin (FG) by ¹H-NMR, ¹³C-NMR, and EI-MS analyses. Compared with α-tocopherol, the isolated antioxidants exhibited high antioxidative activity for the radical scavenging capacity of DPPH and superoxide, but low activity for inhibiting the autoxidation of docosahexaenoic acid (DHA). The isolated antioxidants were produced by the Eurotium species, but not by the Aspergillus species. DAG and TAG exhibited higher radical scavenging capacity than the other antioxidants and were abundantly contained in the extracts of E. herbariorum NE-1 and NE-4.

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Soybean protein (SPI) and diacylglycerol (DAG) are functional components with benefits for lipid metabolism. Since simultaneous intake of such components is expected to exert effects additively and/or synergistically in lifestyle-related diseases, we examined the effects of simultaneous intake of SPI and DAG on lipid profiles. Five-week-old male Wistar rats were fed experimental diets with and without cholesterol for 28 d. In the rats fed cholesterol-free diets, significant interactions between dietary oil and protein were observed in the serum triacylglycerol (TG), hepatic cholesterol, and TG concentrations, whereas in the rats fed cholesterol diets, the serum and hepatic lipid concentrations were significantly lower in rats fed SPI than in those fed casein. Although our results suggest that simultaneous intake of SPI and DAG has slightly ameliorating effects on lipid profiles in rats, simultaneous intake of foods or foods components with similar functions are not necessarily effective.

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Grape seed proanthocyanidin extracts (GSPEs) have been reported to be effective in treating arteriosclerosis, while little is known about therapeutic agents against diabetic macrovascular complications. We used streptozocin to induce diabetic rats. GSPEs (250 mg/kg of body weight) were administrated to diabetic rats for 24 weeks. Aortic blood pressure and pulse wave velocity (PWV) were determined in anesthetized rats. Serum glycated hemoglobin and advanced glycation end products (AGEs) were determined. An electronic microscope was used to observe the changes in aortic ultrastructure. Immunohistochemistry was used to evaluate the receptor of advanced glycation end product (RAGE) protein expression in aortic tissue. GSPEs significantly decreased aortic PWV, blood pressure, and aortic medial thickness (P<0.05), and inhibited the migration of vascular smooth muscle cells. GSPEs significantly reduced the AGEs (P<0.05) and the expression of RAGE in aortas of diabetic rats. GSPEs play an important role against diabetic macrovascular complications. This study may provide a new recognition of natural medicine for the treatment of diabetic macrovascular complications.

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The aim of the present study was to investigate different yam treatments, including powdered-yam-products (PYP) and liquid-yam-products (LYP), with respect to spontaneously hypertensive rats (SHRs) blood pressure. PYP included alcohol-insoluble-solids of yam tuber, hot-air-drying (HAD) of yam tuber slices, steam-cooked once or twice followed by HAD which were subsequently powdered. LYP included water extracts of yam tuber (WEY) heated at 90 °C (WEY90H) or 95 °C for 10 min (WEY95H), and then stored at 4 °C for different numbers of day. PYP, WEY, and WEYH were found effectively to reduce the blood pressure of SHR and should be beneficial in food processing in the development of functional foods for blood pressure regulation.

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Ferulic acid was orally administered to mice in order to investigate its effects on exercise endurance capacity. When a single administration of ferulic acid was given to the mice in an adjustable-current water pool, the duration of exhaustive swimming was longer than that exhibited by the mice in the control group. Also, when the mice were exhaustively exercised for 3 consecutive days, no change in swimming time was found in the ferulic acid-administered group on the final day, and a large decrease in the untreated mice. Administration of ferulic acid efficiently activated the hepatic antioxidative defense system during exercise. The mice that received ferulic acid showed significant increases in the activity of hepatic antioxidant enzymes such as superoxide dismutase, catalase, and glutathione-S-transferase. Furthermore, an increased glutathione level was observed, while the malondialdehyde content was reduced. These results suggest that ferulic acid possesses stimulatory effects that can enhance exercise endurance capacity and reduce fatigue by elevating antioxidative potentials.

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We evaluated the antioxidative activity of a water soluble polysaccharide fraction (WSP) from pumpkin fruits (Cucurbita maxima Duchesne). In the WSP, DPPH radical scavenging and superoxide dismutase-like activity increased depending on the total sugar content. Furthermore, the WSP can serve as an inhibitor of ascorbic acid oxidation. The efficacy was also affected by the total sugar content.

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We analyzed the effects of thiol compounds on the biological activities of 6-(methylsulfinyl)hexyl isothiocyanate (6-MITC). Thiol compounds abolished the cytotoxic activity of 6-MITC, but did not abolish its activity augmenting cellular total glutathione levels and gamma-glutamylcysteine ligase gene expression. Thiol compounds might play an important role in the augmentation of several significant biological activities by overcoming the inherent limitations of 6-MITC.

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In this study, we examined the effects of theaflavins, polyphenols in black tea, on α melanocyte-stimulating hormone (αMSH)-induced melanogenesis in mouse B16 melanoma cells. Among theaflavins, theaflavin-3,3′-digallate (TF-3) exhibited a potent inhibitory effect on melanogenesis. Our results indicate that the inhibitory effect of TF-3 on melanogenesis is due to suppression of tyrosinase protein and mRNA levels.

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Diverse immune responses to an orally administered heat-killed cell preparation of Enterococcus faecalis strain EC-12 (EC-12) among jejunal-Peyer’s patches (PPs), ileal-PPs, mesenteric lymph nodes (MLNs), and spleen were compared by real-time PCR in mice. Intriguingly, distinct responses to EC-12 were observed in the various tissues. This study indicates a site-specific response to orally administered bacteria, particularly in jejunal- and ileal-PPs.

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Dihomo-gamma-linolenic acid (DGLA)-enriched oil (50 or 150 mg as free DGLA) was administered to healthy men for 4 weeks. The DGLA content in serum phospholipids dose-dependently increased and returned to the initial level after a 4-week washout. No side effects or changes in platelet aggregation were observed. These results indicate that oral supplementation with DGLA oil can safely increase serum DGLA content.

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When tetrathionate-grown Acidithiobacillus ferrooxidans ATCC 23270 cells were incubated with ferric ions and tetrathionate at pH 3.0, ferrous ions were produced enzymatically. Fe³⁺-reductase, which catalyzes Fe³⁺ reduction with tetrathionate, was purified to homogeneity not only from tetrathionate-grown, but also from sulfur- and iron-grown A. ferrooxidans ATCC 23270 cells. The results for apparent molecular weight measured by SDS–PAGE (52.3 kD) and the N-terminal amino acid sequences of the purified enzymes from iron-, sulfur, and tetrathionate-grown cells (AVAVPMDSTG) indicate that Fe³⁺-reductase corresponds to tetrathionate hydrolase. The evidence that tetrathionate-grown A. ferrooxidans ATCC 23270 cells have high iron-oxidizing activity at the early log phase, comparable to that of iron-grown ATCC 23270 cells, is supported by our finding that tetrathionate hydrolase produces Fe²⁺ from tetrathionate during growth on tetrathionate. This is the first report on ferric reductase activity associated with tetrathionate hydrolase.

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Sequence comparison of individual genes in the prfA virulence gene cluster (pVGC), a central virulence gene cluster, from different Listeria species indicated that priming sites within the genes appeared to be specific for Listeria monocytogenes exclusively. Therefore, the pVGC was targeted for polymerase chain reaction (PCR) assays to detect and specifically identify L. monocytogenes. Each gene of the pVGC was specifically amplified in L. monocytogenes but not in other Listeria species.

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Rat Δ6 desaturase was introduced in “oleaginous” Saccharomyces cerevisiae genetically modified by the snf2 disruption, DGA1 overexpression, and LEU2 expression to improve stearidonic acid (18:4n-3 (Δ6, 9, 12, 15)) production. When this transformed yeast was cultured in the presence of 0.7 g/l α-linolenic acid for 7 d, 0.4 g of α-linolenic acid was accumulated and 44 mg of stearidonic acid was produced, mainly as a triacylglycerol in the 1 liter broth.

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