Effect of Glucose on the Uricase Formation by Streptomyces sp

The effect of glucose on the formation of uricase by a strain of Streptomyces sp. incubated under conditions of nitrogen limitation was investigated. Glucose stimulated uricase formation in the presence of potassium ion and inhibited it in the absence of the ion. Glucose metabolism by the organism was altered in the absence of the ion, and this appeared to cause the inhibition of the enzyme formation. The stimulatory effect of glucose in the presence of potassium ion was to shorten the lag period. Comparisons of the enzyme formation with and without urate in the presence and absence of glucose revealed that glucose promoted the utilization of exogenous urate as the inducer. The effect of glucose appeared to require protein synthesis, since it was prevented by chloramphenicol. Cyclic adenosine 3′,5′-mono-phosphate showed apparently no effect on uricase formation of this organism.     

A New Enzyme,d-Fructose Dehydrogenase

Genetic relatedness of 14 yeast strains and 2 mold strains was studied by the DNA-DNA hybridization method. The hybridization was performed between mitochondrial-DNA-free, ³²p-labeled DNA of Saccharomyces cerevisiae IAM 4009 and cold DNA of other strains. The DNA homology indices deviated considerably even among S. cerevisiae strains having similar GC contents, but, in general, yeast strains known to be able to mate with S. cerevisiae, showed high homology indices (35∽70%). Other species of Saccharomycetaceae and 6 asporogenous yeast strains exhibited values of 10∽20%. The relatedness suggested from these results was confirmed by the competition experiments and also by the hybridization with ³²P-DNA of Candida pulcherrima IFO 0561. DNA’s of Aspergillus oryzae I and Neurospora crassa IFO 6067 also exhibited low but appreciable homology indices (5∽7%). These results were discussed from the aspects of phylogenetics and also of gene conservation in microorganisms.     

Effects of CH-19 Sweet,a Non-Pungent Cultivar of Red Pepper,in Decreasing the Body Weight and Suppressing Body Fat Accumulation by Sympathetic Nerve Activation in Humans

‘CH-19 Sweet’ is a non-pungent red pepper and enhances the energy expenditure in humans in like manner to the pungent red pepper. We investigated in this study the effects of a repeated intake of CH-19 Sweet for two weeks on the body weight and body fat in humans. Changes in the autonomic nervous activity after ingesting CH-19 Sweet were also measured by a power spectral analysis. We established a new protocol which allows the precise detection of weight change in humans by using fewer subjects. These methods were used to show that the repeated intake of CH-19 Sweet reduced the body weight and suppressed body fat accumulation. Furthermore, the body weight loss due to the repeated intake of CH-19 Sweet was significantly correlated with the sympathetic nervous response after its ingestion. We propose that the repeated intake of CH-19 Sweet reduced the body weight and suppressed body fat accumulation by sympathetic nervous activation in humans.     

Protective effect of capsinoid on lipid peroxidation in rat tissues induced by Fe-NTA

The activity of a single IP administration (15 or 30 mg/Kg body weight) of vanillyl nonanoate, a simplified analog of capsiate, on ferric nitrilotriacetate (Fe-NTA)-mediated oxidative damage was investigated. A sub-lethal dose of Fe-NTA (15 mg Fe/Kg body weight) was administered IP to rats; animals were sacrificed, and kidney and plasma were collected 1 h after injection. In response to the Fe-NTA administration, a reduction of the levels of total lipids, total unsaturated fatty acids and cholesterol was observed, accompanied by a rise in the concentrations of malondialdehyde (MDA), conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol in plasma and kidney 1 h after administration. A pre-treatment with synthetic capsiate (SCPT) showed remarkable protective effect on the reduction of the levels of total lipids, total unsaturated fatty acids and cholesterol, and the cellular antioxidant vitamin E, inhibiting the increase of MDA, conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol in the plasma and kidney. The protective effect of SCPT and two analogues (vanillyl alcohol and vanillin) during the linoleic acid and cholesterol oxidation was investigated in in vitro systems, providing evidence of definite structure-activity relationships.     

Antifeedants of Finger Millet,Eleusine coracana GAERTN,Against Brown Planthopper,Nilaparvata lugens (STÅL)

Nine compounds isolated from finger millet as antifeedants for brown planthopper have been identified as known compounds, l-malic acid, isocitric acid, 4-hydroxybenzoic acid, vanillic acid, 4-hydroxy- benzaldehyde, and vitexin, and new constituents, 2-O-[4-hydroxy-(Z and E)-cinnamoyl]glyceric acid and 8-C-β-d-[6″-O-(3-hydroxy-3-methyl)glutaroyl]glucopyranosylapigenin.     

天然辣椒素酯的酶促合成与生物活性

研究了天然辣椒素经化学．酶法转化为天然辣椒素酯类物质的方法。在30℃,香草醇、脂肪酸酯分别为50、75mmol／L的100mL脱水丙酮溶液,以1g固定化的脂肪酶Novozyme435为催化剂,摇床转速为200r／min条件下反应24h,目标化合物产率可达63％。经硅胶柱色谱分离纯化后,所得产物经质谱确证其含有天然辣椒素酯（capsiate）、二氢辣椒素酯（dihydrocapsiate）、降二氢辣椒素酯（nordihydrocapsiate）、高二氢辣椒素酯（homodi-hydrocapsiate）等。制备HPLC分离后得到辣椒素酯和二氢辣椒素酯,以^1HNMR及MS确定结构。活性测试表明辣椒素酯类物质具有激活PPARγ的生物活性及体外抑制乳腺癌细胞（MCF-7）和肝癌细胞（HepG2）的活性。     

CH-19 Sweet,a Non-Pungent Cultivar of Red Pepper,Increased Body Temperature and Oxygen Consumption in Humans

We investigated the effect of CH-19 Sweet, a nonpungent cultivar of red pepper, on body temperature and oxygen consumption in humans. CH-19 Sweet was given to 11 healthy volunteers, and core body temperature, body surface temperature and oxygen consumption were measured. The control group ingested California-Wandar, which contained neither capsaicin nor capsiate. The core body temperature in the CH-19 Sweet group was significantly higher than that in the control group (P<0.01). The forehead temperature measured by infrared thermography in the CH-19 Sweet group was significantly higher than that in the control group. The body surface temperature was increased for about 20 min after consumption of CH-19 Sweet intake, and the neck temperature was significantly higher (P<0.001) than when the subjects consumed California-Wandar. We also measured respiratory gas by indirect calorimetry while subjects wore a face mask. A significant difference was detected in oxygen consumption between the two groups, and the value was significantly higher in the CH-19 Sweet group (P<0.03). These results suggest that CH-19 Sweet increased thermogenesis and energy consumption.     

Circular Dichroism of the Polyoximic Acid Moiety in Polyoxins

Incubation of alkyl aryl sulfides with growing cells of Corynebacterium equi IFO 3730 afforded the corresponding sulfoxides and sulfones. The selectivity for the formation of sulfoxides over sulfones was higher with sulfides which have shorter alkyl chains. When methyl sulfides were used as substrates, formation of the corresponding sulfones was completely suppressed. Sulfoxides were revealed to have 87 ~ 100% optical purities as to the (R) absolute configuration by HPLC analysis. The culture conditions seriously influenced the yield of oxidation products. High conversion of sulfides was attained when the reaction was carried out with growing cells in the logarithmic phase, in medium containing hexadecane as the carbon and energy source.