首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 23 毫秒
1.
生态产品价值实现是指在维持生态系统稳定性和完整性的前提下,通过合理开发利用生态产品,将其生态价值转化为经济效益的过程。生态产品价值实现机制包含了促进生态产品价值实现的政策、市场和技术机制。生态产品通过各种途径实现的经济价值总和称为生态产品价值实现量。生态产品价值实现量与生态产品总值(GEP)的比值为生态产品价值实现率。评估生态产品价值实现率是评判生态产品价值实现状况的基础,是评估生态产品价值实现机制是否有效运转的重要前提。提出生态产品价值实现率的概念和核算方法,以浙江省丽水市为例,在核算GEP的基础上,评估生态产品价值实现量与实现率来分析丽水市生态产品价值实现状况、问题及影响因素,提出提高生态产品价值实现率的对策建议。研究表明,丽水市2019年GEP为4110.21亿元,生态产品价值实现量为1017.49亿元,生态产品价值实现率为24.76%。丽水生态产品价值实现模式主要有市场交易和政府补偿两种模式。市场交易模式贡献了95.84%的生态产品价值实现量,是目前丽水市最有效的生态产品价值实现模式,但存在价值实现效率不均衡、对于缺乏市场或是市场机制不成熟的生态产品不适用等问题。政府补偿模式贡...  相似文献   

2.
冻干神经生长因子活性稳定性试验研究   总被引:6,自引:1,他引:5  
用不同的物质作保护剂冻干纯化鼠神经生长因子,经检定以人血白蛋白作为赋形剂和保护剂冻干神经生长因子制品外观洁白细腻,结构强度良好,生物活性符合要求,残存水分低于3%。采用留样观察法检测其稳定性,将制品放置4℃~8℃,在0、0.5、1、2、3、6、9、12、18、24、25个月分别测定其各自的活性。结果表明神经生长因子冻干制品在4℃~8℃保存,25个月仍然保持原有生物活性  相似文献   

3.
Pseudomonas sp. strain KC transforms carbon tetrachloride into carbon dioxide and nonvolatile products, without chloroform as an intermediate. To define the pathway for hydrolysis, nonvolatile products were analyzed. Condensation products containing the carbon atom of carbon tetrachloride as carbonyl and thioxo moieties were identified, indicating the intermediacy of phosgene and thiophosgene in the pathway.  相似文献   

4.
Pollen beetles, Meligethes spp. (Coleoptera: Nitidulidae), are among the most damaging pests of oilseed rape (Brassica napus L.). Increasing populations of pyrethroid‐resistant pollen beetles coupled with the prohibition of synthetic pest control products in organic farming means that other direct control methods are needed. A laboratory study was therefore conducted to evaluate the effect of natural products, combinations of natural products and additives as well as natural and synthetic insecticides on mortality of pollen beetles. In addition, field trials under both integrated and organic production were conducted to evaluate the efficacy of six natural products, nine combinations of natural products, two synthetic insecticides (integrated‐production trials only), two natural insecticides and two additives to reduce pollen beetles. The laboratory trial, using both a curative and preventive approach, showed that two of the eight natural products (lavender oil and stone meal) caused a mortality of over 98% within the first day of application. The other natural products were only partially effective compared with the untreated control. In the field trials, the natural products reduced the number of pollen beetles 1 day after application compared with the untreated control in both trial years and production systems. Promising substances were stone meal, Silico‐Sec and liquid manure. Nevertheless, the efficacy was not consistent, and no effect on oilseed rape yield was observed. In spite of this, these products have the potential to control pollen beetles under field conditions with comparable effects to synthetic insecticides. Further research should therefore focus on timing and frequency of applications as well as on the formulation of the natural products to increase the persistency of the products under field conditions.  相似文献   

5.
Trametes villosa laccase was used for direct azo dye degradation, and the reaction products that accumulated after 72 h of incubation were analyzed. Liquid chromatography-mass spectrometry (LC-MS) analysis showed the formation of phenolic compounds during the dye oxidation process as well as a large amount of polymerized products that retain azo group integrity. The amino-phenol reactions were also investigated by 13C-nuclear magnetic resonance and LC-MS analysis, and the polymerization character of laccase was shown. This study highlights the fact that laccases polymerize the reaction products obtained during long-term batch decolorization processes with azo dyes. These polymerized products provide unacceptable color levels in effluents, limiting the application of laccases as bioremediation agents.  相似文献   

6.
Thermophilic (55 degrees C) anaerobic enrichment cultures were incubated with [C-lignin]lignocellulose, [C-polysaccharide]lignocellulose, and kraft [C]lignin prepared from slash pine, Pinus elliottii, and C-labeled preparations of synthetic lignin and purified cellulose. Significant but low percentages (2 to 4%) of synthetic and natural pine lignin were recovered as labeled methane and carbon dioxide during 60-day incubations, whereas much greater percentages (13 to 23%) of kraft lignin were recovered as gaseous end products. Percentages of label recovered from lignin-labeled substrates as dissolved degradation products were approximately equal to percentages recovered as gaseous end products. High-pressure liquid chromatographic analyses of CuO oxidation products of sound and degraded pine lignin indicated that no substantial chemical modifications of the remaining lignin polymer, such as demethoxylation and dearomatization, occurred during biodegradation. The polysaccharide components of pine lignocellulose and purified cellulose were relatively rapidly mineralized to methane and carbon dioxide; 31 to 37% of the pine polysaccharides and 56 to 63% of the purified cellulose were recovered as labeled gaseous end products. An additional 10 to 20% of the polysaccharide substrates was recovered as dissolved degradation products. Overall, these results indicate that elevated temperatures can greatly enhance rates of anaerobic degradation of lignin and lignified substrates to methane and low-molecular-weight aromatic compounds.  相似文献   

7.
Two Yersinia enterocolitica strains were able to utilize the products of cephalothin degradation. The utilization of these products was shown by an increase of oxygen uptake by Y. enterocolitica with cephalothin as the only substrate, and by the growth of both strains with the hydrolysis products of cephalothin as sole energy and carbon sources. Nuclear magnetic resonance analysis of the cephalothin degradation reaction demonstrated the progressive disappearance of hydrolysis products. However, the products of benzylpenicillin degradation could not be utilized by Y. enterocolitica.  相似文献   

8.
The aim of this study was to survey the flavonol compositions of Ginkgo biloba products, especially those on the Japanese market. Sixteen food products, six medicinal products, and raw Ginkgo biloba leaves were examined by ultra-high-performance liquid chromatography coupled with ultra-violet detection and time-of-flight mass spectrometry. Eleven flavonol glycosides, three biflavones, and a flavonol aglycone were qualified by analysis of accurate mass spectra. The quantitative data obtained were then applied to multivariate data analysis, and the flavonol compositions of the food and medicinal products were classified into four groups. Most of the food products were classified into the same group as the medicinal products, which contained high percentages of flavonol glycosides. On the other hand, some food products contained high percentages of biflavones or an aglycone.  相似文献   

9.
Phycomyces blakesleeanus transformed progesterone, testosterone and androstenedione into mixtures of products. Five monohydroxylated metabolites were obtained in reasonable yields from the progesterone transformation. Only 7 alpha- and 15 beta-hydroxyprogesterone have been reported previously from this organism. We find that it gives these two metabolites and also 6 beta-, 14 alpha- and 15 alpha-hydroxyprogesterone as major products. Five compounds were also purified from testosterone transformation mixtures. Two of these were monohydroxylated, two were ring A dehydrogenation products, and two were oxidised at C-17. The products were identified as 6 beta-hydroxytestosterone, 7 alpha-hydroxytestosterone, androsta-1,4-diene-3,17-dione (1-dehydroandrostenedione), 17 beta-hydroxyandrosta-1,4-diene-3-one (1-dehydrotestosterone) and androstenedione. All five metabolites were produced in reasonable yields, although hydroxylation was the minor transformation in this case. Only two significant products were formed from androstenedione. Both were reduced at C-17; one was also monohydroxylated. They were testosterone and 14 alpha-hydroxytestosterone. The testosterone and androstenedione transformation products have not been reported previously for this organism. We also report for the first time the preparation of P. blakesleeanus cell-free extracts which transformed progesterone reasonably efficiently and faithfully in vitro, although the proportions of each product varied from one extract to another.  相似文献   

10.
1. Significant differences between species were observed in the profile of steroids produced from progesterone by adrenal microsomes as well as in the effects elicited by Aroclor 1254 on cytochrome P-450-mediated activities. 2. In the guinea-pig, the major metabolites were products of the corticosteroid pathway but products of the androgenic pathway were also detected; in the barn owl products of both pathways were also formed while in the marsh turtle only products of the corticosteroid pathway were detected. 3. The effect of Aroclor 1254 on P-450C21 activity in the turtle and barn owl was inductive in contrast to the inhibitory effect observed in the guinea-pig.  相似文献   

11.
目的 探索粪微生态制品体外保存方法,为粪微生态制品的保存及运输提供依据。方法 将新鲜粪微生态制品按照加入甘油、蔗糖保护剂的不同以及制备冻干粉的方法分为6组,用10倍稀释法稀释粪菌液,微量点样法将各浓度的粪菌液涂于Wilkins-Chalgren培养基,30℃恒温箱中培养并计数。在保存2周、1个月、2个月、3个月时复苏部分微生态制品,用同样的方法培养并计数。结果 粪微生态制品活菌数随时间递减,在2周内下降速度最快,递减105~107数量级。结论 甘油、蔗糖这两种保护剂以及冻干粉的制备对粪微生态制品的保存差异不大,新鲜粪微生态制品仍为最佳选择。  相似文献   

12.
Summary Large amounts of data indicated that most of the metabolic processes of the acidogenic (acid producing) and the solventogenic (solvent producing) fermentations were regulated by product accumulation. A simple unstructured model simulated microbial growth, product formation and substrate utilization in six different fermentations, where five different microorganisms produced various combinations of ten different products. Specific growth rates of these microorganisms decreased proportionally with overall product accumulation. The products were excreted in non-growth associated pattern. Excretion of some of these products were inhibited by the overall product accumulation similarly as the microbial growth. A substrate consumption model which considered the biomass and individually all the products as separate substrate sinks simulated the data satisfactorily.  相似文献   

13.
The present study was undertaken to investigate the viability of the use of two waste products, cheese whey and composted organic waste, as nutrient sources in the induction of biological films on quartz surfaces, with the final aim of reducing the visual impact generated by quartz mining. Experiments were carried in laboratory in which quartz samples were colonized with microorganisms (mainly cyanobacteria) forming biofilms. Previous studies have shown that a nutritional supplement must be added for good development of biofilms and, therefore, application of the two waste products was compared with application of the chemical nutrient medium on which these types of microorganisms are usually cultivated. Both products provided better results than the culture medium, in terms of the speed of formation of the biofilm, faster with the waste products, and the degree of cover of the brilliant white colour of the quartz, better masked by the biofilms formed when the waste products were applied as a darker biofilm was obtained.  相似文献   

14.
CASE, a structure-activity relational system, was used to predict the proportion of substances to be carcinogenic and mutagenic among plant pesticides (phytoalexins) and other natural products compared to that of randomly selected chemicals. There were no significant differences between phytoalexins and other natural products. On the other hand, the natural products, as a group, were predicted to be less mutagenic and carcinogenic than randomly selected chemicals. 37% of natural products are predicted to be rodent carcinogens.  相似文献   

15.
Microorganisms capable of utilizing pristane (2,6,10,14-tetramethylpentadecane) as a sole source of carbon and energy were isolated from soil specimens. A strain BPM 1613, tentatively classified in the genus Nocardia, accumulated several oxidation products of pristane in the culture fluid. Silica gel chromatography of the ethyl ether extract from the culture fluid yielded pristanol and pristanic acid as major products and pristyl pristanate and pristyl aldehyde as minor products. The confirmations on the estimated structures of these oxidation products are described in detail.  相似文献   

16.
This study assesses the policy/legal status of both multistream residues and potential secondary products (“symbiosis products”) and whether there could be environmental benefits associated with the utilization of residues from integrated pulp and paper and carbon steel mills as raw materials for such secondary products. Waste‐related European Union (EU) and Finnish policy and legal instruments were reviewed to identify potential constraints for, and suggested next steps in, the development of potential process industry residue‐based symbiosis products. The products were soil amendment pellets, low‐grade concrete, and mine filler. A global warming potential (GWP) assessment and an exergy analysis were applied to these potential symbiosis products. Some indicative GWP calculations of greenhouse gas emissions associating similar and/or analogous products based on virgin primary raw materials, more energy‐intensive processes, and the alternative treatment of these residues as wastes are also presented. This study addresses GWP, exergy, and legal aspects in a holistic manner to determine the potential environmental benefits of secondary products within the EU legal framework. The GWP assessment and exergy analysis indicate that the utilization of multistream residues causes very low environmental burdens in terms of GWP. The utilization option can have potential environmental benefits in terms of GWP through process replacement and avoided landfilling and waste treatment impacts, as well as potentially through emission reductions from product replacement if suitable and safe applications can be identified. Waste regulation does not define the legal requirements under which utilizing residues in such novel concepts as introduced in this study would be possible, nor how waste status could be removed and product‐based legislation be applied to the potential products instead.  相似文献   

17.
Reaction of protein amino groups with glucose (the Maillard reaction) leads from early stage products such as Schiff base and Amadori products to advanced glycation end products (AGE), structures implicated in diabetic complications and the aging process. We have prepared the polyclonal anti-AGE antibody and the monoclonal anti-AGE antibody against AGE-bovine serum albumin and made an immunochemical approach to characterize AGE structures. Both polyclonal and monoclonal antibodies reacted with AGE-proteins such as AGE-bovine serum albumin, AGE-human serum albumin, and AGE-hemoglobin but not with unmodified counterparts. Treatments of these AGE-proteins with borohydride had no effect on the immunoreactivity. Moreover, fructosyl-epsilon-caproic acid, a synthetic Amadori compound, did not serve as an antigen, indicating that these antibodies were specific for AGE products but not for early stage products of the Maillard reaction. In addition, these antibodies were also able to recognize AGE products prepared either from alpha-tosyl-1-lysine, alpha-tosyl-1-lysine methyl ester, monoaminocarboxylic acid such as epsilon-aminocaproic acid, gamma-amino-n-butyric acid, and beta-alanine. Thus, these results strongly suggest the presence of a common structure in AGE preparations, regardless of whether AGE products are generated from proteins, amino acids, or monoaminocarboxylic acids.  相似文献   

18.
Effects of hypochlorous acid and of the myeloperoxidase-hydrogen peroxide-chloride system on mono- and polyunsaturated phosphatidylcholines were analyzed by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Chlorohydrins and glycols were detected as main products according to the characteristic shift of molecular masses. Mainly mono-chlorohydrins result upon the incubation of HOCl/(-)OCl with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, whereas only traces of mono-glycols were detected. 1-Palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine yielded a complex mixture of products. Mono-chlorohydrins and glycols dominated only at short incubation, while bis-chlorohydrins as well as products containing one chlorohydrin and one glycol moiety appeared after longer incubation. Similarly, a complex product mixture resulted upon incubation of 1-stearoyl-2-arachidonoyl-sn-glycero-3-phosphocholine with hypochlorous acid. Additionally, tris-chlorohydrins, products with two chlorohydrin and one glycol moiety, as well as lysophosphatidylcholines and fragmentation products of the arachidonoyl side chain were detectable. Mono-chlorohydrins of 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine were detected after the incubation of the latter phospholipid with the myeloperoxidase-hydrogen peroxide-chloride system at pH 6.0. These chlorohydrins were not observed in the absence of chloride, hydrogen peroxide, or myeloperoxidase as well as in the presence of methionine, taurine, or sodium azide. Thus, mono-chlorohydrins in 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine produced by hypochlorous acid from the myeloperoxidase-hydrogen peroxide-chloride system can also be detected by means of MALDI-TOF MS.  相似文献   

19.
The effects of protein deficiency on the biosynthesis of metabolites of arachidonic acid by rat pleural polymorphonuclear leukocytes stimulated with calcium ionophore were investigated. The major products of metabolism by lipoxygenase in these cells were leukotriene B4 and 5-hydroxy-6,8,11,14-eicosatetraenoic acid, whereas the major cyclooxygenase products were thromboxane B2 and 12-hydroxy-5,8,10-heptadecatrienoic acid. At high substrate concentrations (100 microM), the formation of all products by polymorphonuclear leukocytes was lower for protein-deficient rats than for controls. Similar results were obtained when products synthesized from endogenous substrate were measured, except that there was no change in the amount of 5-hydroxy-6,8,11,14-eicosatetraenoic acid formed. The biosynthesis of prostaglandins E2 and F2 alpha by homogenates of rat kidney medulla was reduced as a result of protein deficiency. Acetylsalicylic acid inhibited the formation of cyclooxygenase products and stimulated the formation of lipoxygenase products by polymorphonuclear leukocytes. Protein deficiency did not alter the effects of acetylsalicylic acid on the biosynthesis of these products, although at any given concentration the amounts of products formed were less with protein-deficient rats than with rats fed control diets.  相似文献   

20.
Urobilinoids belong to the heterogenous group of degradation products of bilirubin formed in the gastrointestinal tract by intestinal microflora. Among them urobilinogen and stercobilinogen with their respective oxidation products, urobilin and stercobilin, are the most important compounds. The aim of present study was to analyze the products of bacterial reduction of bilirubin in more detail. The strain of Clostridium perfringens isolated from neonatal stools, capable of reducing bilirubin, was used in the study. Bacteria were incubated under anaerobic conditions with various native as well as synthetic bile pigments, including radiolabeled unconjugated bilirubin (UCB). Their reduction products were extracted from media and separated following thin layer chromatography. Pigments isolated were analyzed by spectrophotometry, spectrofluorometry and mass spectrometry. In a special set of experiments, bilirubin diglucuronide was incubated with either bacterial lysate or partially purified bilirubin reductase and beta-glucuronidase to reveal whether bilirubin glucuronides may be directly reduced onto conjugated urobilinoids. A broad substrate activity was detected in the investigated strain of C. perfringens and a series of bilirubin reduction products was identified. These products were separated in the form of their respective chromogens and further oxidized. Based on their physical-chemical properties, as well as mass spectra, end-catabolic bilirubin products were identified to belong to urobilinogen species. The reduction process, catalyzed enzymatically by the studied bacterial strain, does not proceed to stercobilinogen. Bilirubin diglucuronide is not reduced onto urobilinoid conjugates, glucuronide hydrolysis must precede double bond reduction and thus UCB is reduced much faster.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号