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排序方式: 共有633条查询结果,搜索用时 281 毫秒
31.
From the aerial parts of Sideritis ozturkii, three new flavonoids, chrysoeriol 7-O-[2'-O-caffeoyl-O-acetyl-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside], chrysoeriol 7-O[2'-O-caffeoyl-beta-D-glucopyranosyl-(1 -->2)-beta-D-glucopyranoside] and chrysoeriol 7-O[2'-O-p-coumaroyl-6'-beta-O-acetyl-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside] named as ozturkosides A, B and C, respectively, were isolated, along with three known phenylethanoid glycosides, verbascoside, leucoseptoside A, martynoside and five known diterpenoids, 7-epicandicandiol, linearol, sidol, sideroxol, epoxyisolinearol. The structures were elucidated mainly by spectroscopic methods. 相似文献
32.
Kurbanoglu EB 《Bioresource technology》2004,92(1):97-101
The potential use of ram horn hydrolysate (RHH) as a supplement for improvement of citric acid production by Aspergillus niger NRRL 330 was studied. For this purpose, first RHH was produced. Ram horns were hydrolyzed by treating with acid (6 N-H2SO4) and the RHH was obtained. With the addition of RHH to the fermentation medium with a final concentration of 4% (optimal concentration), citric acid value reached a maximum value (94 g/l), which is 52% higher than that of the control experiment. The addition of 4% (v/v) RHH enhanced citric acid accumulation, reduced residual sugar concentration and stimulated mycelial growth. Adding 4% RHH had no adverse effects on A. niger. As a result, RHH was found to be suitable as a valuable supplement for citric acid production in the submerged fermentation. 相似文献
33.
AIMS: To determine the effect of environmental conditions on the production of extracellular lignocellulose-degrading enzymes by Streptomyces sp. F2621 and to assess the potential use of these enzymes in the hydrolysis of lignocellulose material. METHODS AND RESULTS: The production of extracellular lignocellulose-degrading enzymes, endoxylanase, endoglucanase and peroxidase during the growth of Streptomyces sp. F2621 in basal salts-yeast extract medium containing different carbon sources and the effect of a number of environmental parameters (e.g. carbon sources and concentrations, pH and temperature) were investigated. The highest endoxylanase (22.41 U ml(-1)) and peroxidase (0.58 U ml(-1)) activities were obtained after 2-4 days of incubation at 30 degrees C in a basal salts medium containing 0.4% (w/v) oat spelt xylan and 0.6% (w/v) yeast extract, corresponding to C : N ratio of 6 : 1. Cell-free extracellular enzyme preparations from the strain were capable of releasing both sugar and aromatic compounds during incubation with eucalyptus paper pulp, straw and xylan. Overall, 9.3% hydrolysis of xylan occurred after 24-h incubation. However the rates of hydrolysis of paper pulp and straw were approximately twofold less than xylan hydrolysis, although the total percentage hydrolysis of available substrate (24.5% and 16.3%, respectively) was greater than xylan hydrolysis. CONCLUSIONS: The high levels of enzyme production achieved under batch cultivation conditions, coupled with no significant production of endoglucanase during the growth phase of organism and the release of both sugar and aromatic compounds from paper pulp and straw signify the suitability for these enzymes for industrial applications such as pulp and paper production. SIGNIFICANCE AND IMPACT OF THE STUDY: The results highlight the environmental conditions for the production of extracellular lignocellulose-degrading enzymes by Streptomyces sp. F2621 and suggest the use of streptomycetes and/or their enzymes in industrial processes. 相似文献
34.
The effect of genistein supplementation on performance and antioxidant status of Japanese quail under heat stress 总被引:2,自引:0,他引:2
Onderci M Sahin K Sahin N Gursu MF Doerge D Sarkar FH Kucuk O 《Archives of animal nutrition》2004,58(6):463-471
Genistein, a phytoestrogen found in soybeans, is a powerful antioxidant. We evaluated the effects of genistein supplementation on performance, carcass characteristics, levels of malondialdehyde (MDA), homocysteine, vitamins C, E, A in Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature of 34 degrees C. Two hundred and forty Japanese quails (10 d old) were randomly assigned to eight treatment groups consisting of 10 replicates of three birds. The birds were kept in an environmental controlled room either for 24 h/d at 22 degrees C with (thermoneutral, TN groups) or for 16 h/d at 22 degrees C and for 8 h/d (09.00 am to 05.00 pm) at 34 degrees C (heat stress, HS groups). Birds were fed either a basal (control) diet (TN and HS) or the basal diet supplemented with 200, 400 or 800 mg of genistein per kg of diet. Heat exposure decreased birds' performance when basal diet was fed. Increase in feed intake and body weight, and improvement of feed efficiency and carcass traits were found in genistein-supplemented quails reared under heat stress conditions. Growth rate and feed efficiency improved in quails reared under thermo-neutral conditions as well. Concentration of serum vitamins C, E, and A increased in supplemented birds reared at high temperature, while non-significant changes occurred in TN groups. With genistein supplementation homocysteine levels in serum and MDA levels in serum and liver decreased in all birds of both TN and HS groups. Effects of genistein were relatively greater in heat-stressed quails than in quails kept under thermo-neutral conditions. Results of the present study suggest that supplementation with genistein can be considered to be protective by reducing the negative effects of oxidative stress induced by heat stress in quail. 相似文献
35.
Siegel DH Ashton GH Penagos HG Lee JV Feiler HS Wilhelmsen KC South AP Smith FJ Prescott AR Wessagowit V Oyama N Akiyama M Al Aboud D Al Aboud K Al Githami A Al Hawsawi K Al Ismaily A Al-Suwaid R Atherton DJ Caputo R Fine JD Frieden IJ Fuchs E Haber RM Harada T Kitajima Y Mallory SB Ogawa H Sahin S Shimizu H Suga Y Tadini G Tsuchiya K Wiebe CB Wojnarowska F Zaghloul AB Hamada T Mallipeddi R Eady RA McLean WH McGrath JA Epstein EH 《American journal of human genetics》2003,73(1):174-187
Kindler syndrome is an autosomal recessive disorder characterized by neonatal blistering, sun sensitivity, atrophy, abnormal pigmentation, and fragility of the skin. Linkage and homozygosity analysis in an isolated Panamanian cohort and in additional inbred families mapped the gene to 20p12.3. Loss-of-function mutations were identified in the FLJ20116 gene (renamed “KIND1” [encoding kindlin-1]). Kindlin-1 is a human homolog of the Caenorhabditis elegans protein UNC-112, a membrane-associated structural/signaling protein that has been implicated in linking the actin cytoskeleton to the extracellular matrix (ECM). Thus, Kindler syndrome is, to our knowledge, the first skin fragility disorder caused by a defect in actin-ECM linkage, rather than keratin-ECM linkage. 相似文献
36.
Single-cell protein production from ram horn hydrolysate by bacteria 总被引:23,自引:0,他引:23
The alcoholysis (transesterification) of the refined cotton seed oil of Turkish origin with primary and secondary alcohols was investigated in the presence of an immobilized enzyme from Candida antarctica, commercially called Novozym 435 in a solvent-free medium. The optimum conditions of the methanolysis were as follows: 30% enzyme based on oil weight; oil/alcohol molar ratio 1:4; temperature: 50 degrees C and reaction time: 7 h. Maximum methyl esters (ME) yield was 91.5%. At the same conditions cotton seed oil was converted with short-chain primary and secondary alcohols to its corresponding esters with conversions between 72% and 94%. Our results indicated that alcoholysis products of cotton seed oil could be used as valuable intermediates in oleochemistry. 相似文献
37.
Demir Z Kurtay A Sahin U Velidedeoğlu H Celebioğlu S 《Plastic and reconstructive surgery》2003,112(2):423-429
Loss of mustache and beard in the adult male caused by severe burn, trauma, or tumor resection may cause cosmetic and psychological problems for these patients. Reconstruction of the elements of the face presents difficult and often daunting problems for plastic surgeons. The tissue that will be used for this purpose should have the same characteristics as the facial area, consisting of thin, pliable, hair-bearing tissue with a good color match. There is a very limited amount of donor area that has these characteristics. A hair-bearing submental island flap was used successfully for mustache and beard reconstruction in 11 male patients during the last 5 years. The scar was on the mentum in four cases, right cheek in two cases, right half of the upper lip in two cases, left cheek in one case, left half of the upper lip in one case, and both sides of the upper lip in one case. The submental island flap is supplied by the submental artery, a branch of the facial artery. The maximum flap size was 13 x 6 cm and the minimum size was 6 x 3 cm (average, 10 x 4 cm) in this series. Direct closure was achieved at all donor sites. Patients were followed up for 6 months to 5 years. No major complication was noted other than one case of temporary palsy of the marginal mandibular branch of the facial nerve. The mean postoperative stay was 7 days. Color and texture match were good. Hair growth on the flap was normal, and characteristics of the hair were the same as the intact side of the face in all patients. The submental island flap is safe, rapid, and simple to raise and leaves a well-hidden donor-site scar. The authors believe that the submental artery island flap surpasses the other flaps in reconstruction of the mustache and beard in male patients. Application of the technique and results are discussed in this article. 相似文献
38.
39.
Baydar T Papp A Aydin A Nagymajtenyi L Schulz H Isimer A Sahin G 《Biological trace element research》2003,92(3):231-244
The present study was undertaken to examine possible aluminum (Al) accumulation in the brain of rats and to investigate whether
subchronic exposure to the metal leads to behavioral and neurophysiological changes in both treated and control groups. Each
of the groups consisted of 10 animals. Aluminum chloride (AlCl3) at a low (50 mg/kg/d) or high (200 mg/kg/d) dose was applied to male Wistar rats by gavage for 8 wk. Al-free water by gavage
was given to the control group throughout the experiment. Behavioral effects were evaluated by open-field (OF) motor activity
and by acoustic startle response (ASR). Electrophysiological examination was done by recording spontaneous activity and sensory-evoked
potentials from the visual, somatosensory, as well as auditory cortex. The Al content of each whole brain was determined by
electrothermal atomic absorption spectrophotometry. Subchronic Al exposure slightly caused some changes in the evoked potentials
and electrocorticograms and in the OF and ASR performance, but these results were not statistically significant. The brain
Al levels of the control and the low and high dose of Al-exposed groups were measured as 0.717±0.208 μg/g (wet weight), 0.963±0.491
μg/g (wet weight) and 1.816±1.157 μg/g (wet weight), respectively. 相似文献
40.
Sezai Ercisli Ahmet Esitken Rustem Cangi Fikrettin Sahin 《Plant Growth Regulation》2003,41(2):133-137
During the winters of 2001 and 2002, the effects of three strain of Agrobacterium rubi (A1, A16 and A18), a range of IBA concentrations (0, 2000, 4000 and 6000 ppm) alone and in combination with three strains of Agrobacterium rubi and date of cutting collection on the rooting of hardwood stem cuttings of kiwifruit cv. Hayward were evaluated. Treatments of hardwood stem cuttings of kiwifruit cv. Hayward with the bacteria, IBA and IBA plus bacteria were found to promote rooting. Highest rooting percentage was obtained from cuttings treated with 4000 ppm IBA plus A18 in cv. Hayward in both years. Higher rooting percentages were observed when shoots were collected in February rather than in January. 相似文献