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1.
Laboratory experiments showed that butyric acid not only fails to meet the trophic requirements of hydrocarbon-oxidizing microorganisms, but even specifically inhibits their assimilatory and dissimilatory activity. Therefore, butyric acid can be referred to as growth inhibitors. The combined mineralization of carbohydrates and hydrocarbons can be described as follows. Plants polymers are converted to monosugars by heterotrophic soil microorganisms. As the concentration of the monosugars grows and oxygen becomes deficient, the monosugars are no longer oxidized completely but are fermented. As a result, glucose transforms to butyric acid, which inhibits hydrocarbon-oxidizing bacteria. It is concluded that, to be efficient, the cleanup of oil-contaminated soils must include measures to intensify the mineralization of carbohydrates and to inhibit their fermentation. 相似文献
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The effects of the exogenous auxin——NAA, kinetin and wound on the callus formation of the cotyledon of mung bean (Phaseolus radiatus L.) with relation to the biosyntheses of endogeonous tryptophan (Trp) and IAA have been studied. The results indicate that wound plays an important role in the callus formation. The size of wounded surface is directly proportional to the proliferation of the callus tissue. The levels of free Trp and endogenous 1AA decreased in the initial period of the callus formation of mung bean cotyledon but increased in the later period. The substitution of L-Trp for NAA in the culture medium would play almost the same role in the callus proliferation. It has proposed that the exogenous phytohormones affect the biosyntheses of endogenous Trp and IAA, thereafter induce the callus formation. The wound has an important synergism with the phytohormones in this process. 相似文献
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外源咖啡酸和阿魏酸对黑莓汁中花色苷的辅色研究 总被引:2,自引:0,他引:2
为增强黑莓汁中花色苷的稳定,添加适量咖啡酸和阿魏酸到黑莓清汁中,采用可见吸收光谱和高效液相色谱-质谱研究其对黑莓花色苷的辅色作用。研究结果表明:黑莓汁中添加咖啡酸和阿魏酸显著增加了花色苷的最大吸收值(Aλmax),最大吸收波长(λmax)红移,说明咖啡酸和阿魏酸对黑莓汁中花色苷产生了辅色作用,辅色效应随时间的延长和咖啡酸、阿魏酸浓度的增加显著增强。HPLC-DAD-MS分析发现,咖啡酸辅色产生了两种新的花色苷衍生物(矢车菊素-3-O-葡萄糖苷-4-乙烯基儿茶酚和矢车菊-3-O-草酸酐酰葡萄糖苷-4-乙烯基儿茶酚),阿魏酸辅色产生了三种新的花色苷衍生物(矢车菊素-3-O-葡萄糖苷-4-乙烯基愈创木酚、矢车菊-3-O-草酸酐酰葡萄糖苷-4-乙烯基愈创木酚和矢车菊-3-O-阿拉伯糖苷-4-乙烯基愈创木酚),这些衍生物均为羟苯基-吡喃花色苷。 相似文献
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研究菹草提取物的有效成分,测定其总黄酮含量及总酚酸含量,并确定它的乙酸乙酯和石油醚部位的抗氧化活性成分。采用紫外可见分光光度法,以芦丁和没食子酸作为控制材料,测定菹草的石油醚部位及乙酸乙酯部位中总黄酮和总酚酸含量;采用清除DPPH自由基能力测定法、测定总还原能力铁氰化钾法和水杨酸捕捉羟基自由基法来对菹草各组分提取物的抗氧化能力进行研究。菹草中有一定量的黄酮类化合物和酚酸类化合物存在,不同溶剂提取的部位所含有的总黄酮和总酚酸含量是有差异的,石油醚部位的总黄酮含量要高于乙酸乙酯部位的总黄酮含量,并且总酚酸的含量亦是如此;石油醚部位和乙酸乙酯部位的提取物具有清除DPPH、羟基自由基和还原Fe^3+的能力,各部位清除DPPH、羟基自由基的能力和还原Fe^3+的能力随着样品浓度的增大而增大,且乙酸乙酯部位的测定结果均低于石油醚部位。 相似文献
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日本落叶松扦插生根期内源激素和营养物质及酚酸含量变化特征 总被引:2,自引:0,他引:2
以生根能力差异较大的4个日本落叶松无性系为材料,对插穗生根过程中插穗内源激素含量和比值,以及总酚酸和营养物质含量的变化进行分析,以明确插穗不定根形成的主要内源性影响因素,为日本落叶松扦插繁殖技术提供理论依据.结果表明:(1)4个日本落叶松无性系扦插生根能力存在显著差异,‘日宽17-3-1'和‘日抚273 1,较易生根,其生根率达90%,而‘日草103-3-1’和‘日草82 4-3’难生根,其生根率低于20%.(2)在扦插生根过程中,插穗内源脱落酸(ABA)含量随扦插时间的延长而不断升高,并且较易生根和难生根无性系差异明显,与插穗的生根能力有较强的相关性;玉米素(Z)和总酚酸含量随扦插时间的延长而不断降低,并且对插穗生根具有明显的抑制作用;总氮含量表现出不断降低至逐渐稳定的趋势,但与插穗生根能力大小并无较强的相关性.(3)(IAA+Z)/ABA随扦插时间的延长而不断降低,且较易生根型小于难生根型.因此,在生产中以(IAA+ Z)/ABA的比值和总酚酸含量大小可判断日本落叶松插穗的生根能力. 相似文献
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《Free radical research》2013,47(5):299-309
Copper, zinc superoxide dismutase (Cu, ZnSOD) and manganese superoxide dismutase (MnSOD) activities were measured in mouse large intestinal mucosa during dimethylhydrazine (DMH) carcinogenesis. Mice were divided into five groups. Group A was subcutaneously injected with DMH (20mg/kg) weekly and fed with a diet containing 0.2% cholic acid (C) and 0.8% indole (I). Group B was injected with DMH and given indole feeding. Group C was treated with DMH injection and cholic acid feeding. Group D was given DMH injection alone. Group E was an age-matched control group given 0.9% NaCl injection. The experiment last 21 weeks. The Cu, ZnSOD activity of intestinal mucosa in group A animals began to increase significantly at the 7th week of the experiment. In groups B, C and D, however, this enzyme was not elevated statistically until the 16th week, and then each of these groups kept an increased Cu, ZnSOD level the rest of the experimental period. MnSOD activity was elevated statistically in group C animals at the 7th week. The enzyme activity in group A and D animals increased at the 9th week, but the enzyme activity did not increase statistically until the 11th week in group B. After the 16th week of the experiment the increased activity of MnSOD in all experimental groups returned to the level of the control group. Large intestinal cancer tissues had increased Cu, ZnSOD activity and decreased MnSOD activity. 相似文献
9.
Copper, zinc superoxide dismutase (Cu, ZnSOD) and manganese superoxide dismutase (MnSOD) activities were measured in mouse large intestinal mucosa during dimethylhydrazine (DMH) carcinogenesis. Mice were divided into five groups. Group A was subcutaneously injected with DMH (20mg/kg) weekly and fed with a diet containing 0.2% cholic acid (C) and 0.8% indole (I). Group B was injected with DMH and given indole feeding. Group C was treated with DMH injection and cholic acid feeding. Group D was given DMH injection alone. Group E was an age-matched control group given 0.9% NaCl injection. The experiment last 21 weeks. The Cu, ZnSOD activity of intestinal mucosa in group A animals began to increase significantly at the 7th week of the experiment. In groups B, C and D, however, this enzyme was not elevated statistically until the 16th week, and then each of these groups kept an increased Cu, ZnSOD level the rest of the experimental period. MnSOD activity was elevated statistically in group C animals at the 7th week. The enzyme activity in group A and D animals increased at the 9th week, but the enzyme activity did not increase statistically until the 11th week in group B. After the 16th week of the experiment the increased activity of MnSOD in all experimental groups returned to the level of the control group. Large intestinal cancer tissues had increased Cu, ZnSOD activity and decreased MnSOD activity. 相似文献
10.
《Bioscience, biotechnology, and biochemistry》2013,77(10):2560-2563
Chlorogenic acid possessed a weak caffeine-like psychostimulant property when assessed for its effect on spontaneous locomotor activity in mice. In the evaluation of the effects for the major metabolites of chlorogenic acid which were detected upon incubation with rat feces and/or excreted in urine after oral administration to rats, caffeic and m-coumaric acids were found to be the principal active metabolites, while the others contributed little to this caffeine-like psychostimulant activity. 相似文献
11.
Effect of Ultraviolet (UV-B) Radiation on the Formation and Localization of Phenolic Compounds in Tea Plant Callus Cultures 总被引:1,自引:0,他引:1
N. V. Zagoskina G. A. Dubravina A. K. Alyavina E. A. Goncharuk 《Russian Journal of Plant Physiology》2003,50(2):270-275
The effect of ultraviolet (UV-B) radiation on the accumulation and tissue localization of phenolic compounds in two strains of callus cultures of tea plant (Camellia sinensisL.) were investigated. The strains differed in their morphological and physiological characteristics and biosynthetic capacity. UV-B radiation hampered culture growth, decreased the size of callus-forming cells and promoted the accumulation of soluble and, to a lesser extent, polymeric forms of phenolic compounds, such as lignin. This accumulation was accompanied by an increase in the phenolic compound deposition in cell walls and intercellular space and by deposition of a lignin-like material on the surface of callus cultures. The strain characterized by an increased formation of phenolic compounds was more resistant to UV-B radiation as compared to that with lower phenolic productivity. 相似文献
12.
Journal of Plant Growth Regulation - Lepidium sativum L. is an annual herb with various medicinal and industrial applications. In addition, the elicitation process is considered as a highly... 相似文献
13.
光、糖与激素影响植物花色素苷合成与积累的研究进展(综述) 总被引:4,自引:0,他引:4
次生代谢物质花色素苷存在于植物的叶片、花、果实和种子的表皮细胞的液泡中,是一类使这些器官呈现从红色到黑色等系列颜色的水溶性色素。其合成过程不仅受到基因的调控,还受多种因素影响。首先是光通过信号转导途径直接或间接地调节相关酶基因表达的过程;其次是糖,常与光相互作用协调控制花着色;激素也是影响花色素苷合成的一个重要因素,往往通过影响植物体内的代谢过程和植物基因的表达来影响花色素苷的合成和积累。本文综述近20年来该领域的研究进展。 相似文献
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目的:探讨大剂量氨甲环酸对全膝关节置换患者术后纤溶活性与炎症因子的影响。方法:回顾性分析在我院行初次全膝关节置换术的180例患者,按照给药方式分为对照组、常规组、大剂量组,每组各60例。对照组患者直接给予生理盐水,常规组给予10 mg/kg氨甲环酸,大剂量组给予15 mg/kg氨甲环酸。比较三组术后总失血量、隐形失血量、术前与术后3天三组凝血功能(纤维蛋白原、凝血酶原时间、活化部分凝血活酶时间)、纤溶活性[纤维蛋白(原)降解产物(FDP)、D-二聚体]以及炎性因子[C-反应蛋白(CRP)、白介素-6(IL-6)]水平变化及术后2周血栓事件的发生情况。结果:大剂量组与常规组的总失血量与隐形失血量均明显低于对照组,大剂量组总失血量与隐形失血量均低于常规组(P0.05);三组患者纤维蛋白原、凝血酶原时间以及活化部分凝血活酶时间相比差异均无统计学意义(P0.05);术后3天,大剂量组和常规组FDP与D-二聚体、CRP、IL-6水平均显著低于对照组,且与常规组相比,大剂量组水平较低(P0.05);术后2周,三组肌间静脉血栓发生率比较均无显著差异(P0.05)。结论:在全膝关节置换术后使用氨甲环酸可进一步减少术后隐形失血量,且不会增加血栓事件的风险,且随着药物剂量的增加,其止血效果越强,同时具有更为显著的抗纤溶作用与抗炎效果。 相似文献
15.
Effects of indole‐3‐butyric acid on growth,pigments and UV‐screening compounds in Nostoc linckia
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In the present research, the effect of indole‐3‐butyric acid (IBA) on the growth, and the production of some primary and secondary metabolites was studied in Nostoc linckia. In this respect, algae cultures were supplied with 0, 0.01, 0.1, 1, 10, and 100 μM IBA for 14 days. IBA at concentrations of 10 and 100 μM induced algal growth expressed as fresh weight in N. linckia. Treatment with IBA at all concentrations stimulated heterocyst formation. In addition, low concentrations of IBA (0.01, 0.1, and 1 μM) had a stimulatory effect on chlorophyll a and carotenoids accumulation. In contrast, higher concentrations of IBA induced the accumulation of phycocyanin, allophycocyanin, and phycoerythrin in the treated algae. In this case, IBA at the concentration of 10 μM was more effective. A significant decrease in protein content was observed in the algae treated by 0.01 μM IBA. All concentrations of IBA caused a decrease in sugar content, but lower concentrations were more effective. IBA application in all of the concentrations except 100 μM increased oligosaccharide‐linked mycosporine‐like amino acids (OS‐MAAs) content. Lower concentrations had a more significant effect on increasing OS‐MAAs content. However the concentrations of 10 and 100 μM IBA decreased scytonemin content. These results indicated the stimulatory impact of IBA on weight, heterocyst formation, and photosynthetic pigments in N. linckia. 相似文献
16.
研究了蔗糖脂肪酸脂(SFE)对离体和活体大豆蔗糖酶活力和构象的影响。当SFE的浓度大于1.0mmol/L后,开始激活离体蔗糖酶的活力。在大豆的开花期和结荚期,SFE可以增加蔗糖酶的活力。荧光实验结果表明,在小于2mmol/L时,SFE不改变蔗糖酶的荧光最大发射峰峰位和峰高。施用SFE后,大豆叶片中果糖、葡萄糖和蔗糖酶的含量,分别是对照的170%±10%,190%±10%,和260%±20%;而蔗糖的含量几乎不变。对蔗糖酶
的SDS-凝胶电泳图进行扫描分析的结果表明,经SFE处理后的蔗糖酶含量比对照高两倍左右。这些结果说明SFE可以显著增加活体蔗糖酶的活力,但活力的增加既不是因为蔗糖酶构象的改变,也不是蔗糖(作为底物)诱导所致,而是SFE增加了大豆叶片中蔗糖酶的含量引起的。 相似文献
17.
研究了16 g/L甘露醇处理对小麦细胞再分化、细胞IAA氧化酶、IAA过氧化物酶、
谷胱甘肽转移酶和过氧化物酶活性的影响。结果表明,甘露醇处理使小麦细胞再生能力明显降低,引起细胞蛋白质含量、IAA过氧化物酶和GST活性明显降低;但使细胞IAA氧化酶和POD活性明显增高。 相似文献
18.
Methanol Extracts of 28 Hieracium Species from the Balkan Peninsula – Comparative LC–MS Analysis,Chemosystematic Evaluation of their Flavonoid and Phenolic Acid Profiles and Antioxidant Potentials
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Violeta Milutinović Marjan Niketić Ljuboš Ušjak Dejan Nikolić Aleksej Krunić Christian Zidorn Silvana Petrović 《Phytochemical analysis : PCA》2018,29(1):30-47
Introduction
Hieracium s. str. represents one of the largest and most complex genera of flowering plants. As molecular genetics seems unlikely to disentangle intricate relationships within this reticulate species complex, analysis of flavonoids and phenolic acids, known as good chemosystematic markers, promise to be more reliable. Data about pharmacological activity of Hieracium species are scarce.Objective
Evaluation of the chemosystematic significance of flavonoids and phenolic acids of methanol extracts of aerial flowering parts of 28 Hieracium species from the Balkans. Additionally, investigation of antioxidant potentials of the extracts.Methods
Comparative qualitative and quantitative analysis of flavonoids and phenolic acids was performed by LC–MS. Multivariate statistical data analysis included non‐metric multidimensional scaling (nMDS), unweighted pair‐group arithmetic averages (UPGMA) and principal component analysis (PCA). Antioxidant activity was evaluated using three colorimetric tests.Results
Dominant phenolics in almost all species were luteolin type flavonoids, followed by phenolic acids. Although the investigated Hieracium species share many compounds, the current classification of the genus was supported by nMDS and UPGMA analyses with a good resolution to the group level. Hieracium naegelianum was clearly separated from the other investigated species. Spatial and ecological distances of the samples were likely to influence unexpected differentiation of some groups within H. sect. Pannosa. The vast majority of dominant compounds significantly contributed to differences between taxa. The antioxidant potential of the extracts was satisfactory and in accordance with their phenolics composition.Conclusions
Comparative LC–MS analysis demonstrated that flavonoids and phenolic acids are good indicators of chemosystematic relationships within Hieracium, particularly between non‐hybrid species and groups from the same location. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献19.
茶叶多糖的糖醛酸含量测定及抗氧化活性研究 总被引:1,自引:0,他引:1
采用高效液相色谱法对三个产地茶叶多糖的糖醛酸含量进行了测定,该方法具有操作简便、样品无需预处理等特点,稳定性、重现性较好,回收率高,适合于茶叶多糖糖醛酸含量的测定。结果表明不同产地茶叶多糖的糖醛酸含量有明显差异。本文同时研究了不同产地茶叶多糖对超氧自由基和DPPH自由基的清除作用,以评价其抗氧化活性。结果发现不同产地茶叶多糖的抗氧化活性与其糖醛酸含量呈正相关,糖醛酸含量越高,其抗氧化能力越强。 相似文献
20.
外源一氧化氮、水杨酸和过氧化氢对烟草叶片游离氨基酸和可溶性蛋白含量的影响 总被引:12,自引:0,他引:12
测定了NO、SA和H2O2三种信号分子对烟草氮代谢产物游离氨基酸、脯氨酸和可溶性蛋白质含量的影响。结果表明:NO、SA和H2O2能调节烟草脯氨酸、游离氨基酸和可溶性蛋白质含量。低浓度的NO和H2O2处理后12h能提高脯氨酸含量,而较高浓度的NO、SA和H2O2处理降低烟草脯氨酸和游离氨基酸含量;三者对脯氨酸、游离氨基酸和可溶性蛋白质含量的影响具有相似性。 相似文献