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近现代传统琵琶谱的用调机制 被引量:2
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作者 庄永平 《交响(西安音乐学院学报)》 2019年第3期5-12,共8页
以近现代华秋苹《琵琶谱》、李芳园《南北派十三套大曲琵琶新谱》、沈浩初《养正轩琵琶谱》三份主要琵琶乐谱为代表,来说明传统琵琶谱的用调机制。《华氏谱》中存在着较明显的正宫与小工两种命调系统的矛盾,调性概念是建立在正宫调(G调... 以近现代华秋苹《琵琶谱》、李芳园《南北派十三套大曲琵琶新谱》、沈浩初《养正轩琵琶谱》三份主要琵琶乐谱为代表,来说明传统琵琶谱的用调机制。《华氏谱》中存在着较明显的正宫与小工两种命调系统的矛盾,调性概念是建立在正宫调(G调)笛基础上,定弦则按小工调(D调)笛;《李氏谱》中将其他调性均按小工调正调D调来记写,不免产生出某些翻调上的错舛来;《养谱》在调性理论上作了较繁琐的论证,实际仍是受了正宫与小工两种命调系统矛盾的影响。但与《华氏谱》不同的是,它已是建立在小工调笛上的正宫调(G调)来论证的,这就是近现代传统琵琶谱的用调机制。 展开更多
关键词 华氏 李氏 养谱 用调机制 正宫调系统 小工调系统
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Single Polar Compound Bioelectret Material and Its Influence on the Cell Growth 被引量:1
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作者 史向阳 邓百明 孙曹民 《Journal of Beijing Institute of Technology》 EI CAS 1997年第4期31-39,共9页
To explore the influence of compound bioelectret material′s dielectric property on the cell growth,several kinds of compound bioelectret materials of collagen/chitosan were developed Their TSDC(thermally stimulated ... To explore the influence of compound bioelectret material′s dielectric property on the cell growth,several kinds of compound bioelectret materials of collagen/chitosan were developed Their TSDC(thermally stimulated depolarization current)spectra were analyzed,and the compound bioelectret collagen/chitosan whose t α and I α were 37℃ and 2×10 -9 A respectively at polarized state was selected The cell culture study showed that the compound bioelectret material could promote normal cell growth when singly negatively polarized,and could inhibit cancer cell growth when singly positively polarized It proves that the rational designation of compound bioelectret has a broad application for clinical medicine 展开更多
关键词 bioelectret COLLAGEN CHITOSAN TSDC cell culture
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Degradation of lignite model compounds by the action of white rot fungi 被引量:9
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作者 DU Ying, TAO Xiuxiang, SHI Kaiyi, LI Yang School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou 221000, China 《Mining Science and Technology》 EI CAS 2010年第1期76-81,共6页
Three compounds modeled on the lignite structure were chosen for experimental degradation by different fungi strains. Culture conditions and extracellular enzyme activities were optimized. The growth curves of the str... Three compounds modeled on the lignite structure were chosen for experimental degradation by different fungi strains. Culture conditions and extracellular enzyme activities were optimized. The growth curves of the strains were determined to study mycelium dry weight and protein content changes. Gas chromatography and infrared spectroscopy were used to detect changes of functional groups before and after the action of the fungi on the model compounds. Possible decomposition products and degrada-tion mechanisms were proposed. The research findings show that C. Versicolor and Golden Mushroom can grow in presence of the model compounds. The optimum culture conditions were a pH of 6.0, a carbon-nitrogen ratio of five and a Tween-80 concentration of 0.1%. Newly produced substances were found by gas chromatography. Infrared analysis showed that the model compounds degraded under the action of the microorganisms. 展开更多
关键词 COAL BIOTRANSFORMATION white rot fungi mechanism model compound
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Comparison of time-restricted and ad libitum self-feeding on the growth,feeding behavior and daily digestive enzyme profiles of Atlantic salmon 被引量:1
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作者 史策 刘鹰 +5 位作者 衣萌萌 郑纪盟 田会芹 杜以帅 李贤 孙国祥 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期729-736,共8页
Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and,hence,better growth performance,the assumption has rare... Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and,hence,better growth performance,the assumption has rarely been tested.This study compares the effects of time-restricted versus free access self-feeding on the growth,feeding behavior and daily digestive enzyme rhythms of Atlantic salmon(Salmo salar).In an experiment that lasted 6 weeks,fish(109.9 g) were divided into two groups:group 1 had free access to a self-feeder(FA);group 2 received three meals per day(2 h per meal) at dawn,midday and dusk via a time-restricted self-feeder(TR).At the end of the experiment,the fish were sampled every 3 h over a24-h period.The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase,while FA fish displayed no statistically significant rhythms(P>0.05).Pepsin activity of TR fish also showed a significant daily rhythm(P<0.05) with the acrophase at the second feed and a decrease over the next 12 h.Average daily trypsin,lipase and amylase levels of FA fish were significantly lower than those of TR fish(P<0.01);however,the growth performance of both groups was similar(P>0.05).In conclusion,the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance,with the TR group showing comparatively poor blood glucose regulation. 展开更多
关键词 Atlantic salmon (Salmo salar) self-feeding regime feeding behavior digestive physiology daily rhythm
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Assessment of Nutrients of Escamoles Ant Eggs Limotepum apiculatum M. by Spectroscopy Methods
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作者 Virginia Melo-Ruiz Yomas Quirino-Barreda +2 位作者 Concepcion Calvo-Carrillo Karina Sanchez-Herrera Horacio Sandoval-Trujillo 《Journal of Chemistry and Chemical Engineering》 2013年第12期1181-1187,共7页
Edible insects, escamoles ant eggs of the Formicidae family are consumed by cultural tradition at rural communities and by sensory characteristics at high class restaurants of Mexico; however, people ignore the import... Edible insects, escamoles ant eggs of the Formicidae family are consumed by cultural tradition at rural communities and by sensory characteristics at high class restaurants of Mexico; however, people ignore the importance of insect consumption in the nutrition of humans. Laboratory spectroscopy methods in food analysis represent benefits in time and precision. The aim of this study is to assess macronutrients and micronutrients of escamoles and eggs by spectroscopic methods to inform population the benefits they provide in health and to mention the advantage in the use of these techniques at laboratory work. Samples were gather the second week of March and April 2012, at Hidalgo State and analyze moisture and macronutrients by AOAC (Association of Official Analytical Chemistry) methods, amino acids by cation exchange chromatography, tryptophan was determined by a colorimeter method, fatty acids by GC (gas chromatography) using helium as a carrier (AOAC), fat soluble vitamins A, D and E by HPLC (high performance liquid chromatography), and minerals by atomic absorption spectrophotometers and phosphorus by colorimeter (AOAC). Data showed high amount in proteins, lipids and minerals; low in fiber and soluble carbohydrates; contained all essential amino acids. Fatty acids contain monounsaturated and polyunsaturated. Fat soluble vitamins A, D and E. Minerals: sodium, phosphorus, potassium, magnesium, calcium and manganese. Escamoles ant eggs include polyunsaturated fatty acids essential for mental development, vitamin A to prevent eye diseases, vitamin E as antioxidant and vitamin D involved in calcium absorption that low intake, impair grow and bone health. Iron and zinc contained anemia. Regarding the laboratory benefits, needs less expensive chemicals, testing is clean, rapid and easy results of multiple samples, but it is required to handle by qualified chemists. In conclusion, data may change according to biotic and abiotic conditions of the environment; however, escamoles have all nutrients in adequate balance to improve human health; and provide faster and precise results. 展开更多
关键词 Edible insects escamoles ant eggs NUTRITION spectroscopy methods.
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Measurement and feature analysis of absorption spectra of four algal species
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作者 朱建华 周虹丽 +1 位作者 韩冰 李铜基 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第2期350-359,共10页
Two methods for particulate pigments(i.e.,quantitative filter technique,QFT,and in vivo measurement,InVivo,respectively)and two methods for dissolved pigments(i.e.,Acetone Extracts,AceEx,and high-performance liquid ch... Two methods for particulate pigments(i.e.,quantitative filter technique,QFT,and in vivo measurement,InVivo,respectively)and two methods for dissolved pigments(i.e.,Acetone Extracts,AceEx,and high-performance liquid chromatography,HPLC,respectively) were used to obtain the optical absorption coefficient spectra for cultures of four typical algal species.Through normalization and analysis of the spectra,it is shown that(1) the four methods are able to measure optical absorption spectra of particulate and/or dissolved pigments;(2)that the optical absorption spectra of particulate and dissolved pigments were consistent in terms of the peak position in the blue wavelength,and the difference of the peak position in the near infrared wavelength was ~10nm between each other;and(3)that the leveling effect of the absorption spectra of particulate pigments was significant.These four methods can all effectively measure the absorption coefficients of phytoplankton pigments,while each one has its unique advantages in different applications.Therefore,appropriate method should be carefully selected for various application due to their intrinsic difference. 展开更多
关键词 algal species optical absorption coefficient spectral pattern NORMALIZATION
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The metabolite profiling of coastal coccolithophorid species Pleurochrysis carterae(Haptophyta)
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作者 周成旭 罗杰 +3 位作者 叶央芳 严小军 刘宝宁 文欣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期749-756,共8页
Pleurochrysis carterae is a calcifi ed coccolithophorid species that usually blooms in the coastal area and causes aquaculture losses. The cellular calcifi cation, blooming and many other critical species specifi c ec... Pleurochrysis carterae is a calcifi ed coccolithophorid species that usually blooms in the coastal area and causes aquaculture losses. The cellular calcifi cation, blooming and many other critical species specifi c eco-physiological processes are closely related to various metabolic pathways. The purpose of this study is to apply the unbiased and non-destructive method of nuclear magnetic resonance(NMR) to detect the unknown holistic metabolite of P. carterae. The results show that NMR spectroscopic method is practical in the analysis of metabolites of phytoplankton. The metabolome of P. carterae was dominated by 26 metabolites involved in a number of dif ferent primary and secondary metabolic pathways. Organic acids and their derivatives, amino acids, sugars, nucleic aides were mainly detected. The abundant metabolites are that closely related to the process of cellular osmotic adjustment, which possibly refl ect the active ability of P. carterae to adapt to the versatile coastal niche. DMSP(dimethylsulphoniopropionate) was the most dominant metabolite in P. carterae, up to 2.065±0.278 mg/g lyophilized cells, followed by glutamate and lactose, the contents were 0.349±0.035 and 0.301±0.073 mg/g lyophilized cells respectively. Other metabolites that had the content ranged between 0.1–0.2 mg/g lyophilized cells were alanine, isethionate and arabinose. Amino acid(valine, phenylalanine, isoleucine, tyrosine), organic acid salts(lactate, succinate), scyllitol and uracil had content ranged from 0.01 to below 0.1 mg/g lyophilized cells. Trigonelline, fumarate and formate were detected in very low content(only thousandths of 1 mg per gram of lyophilized cells or below). Our results of the holistic metabolites of P. carterae are the basic references for the further studies when multiple problems will be addressed to this notorious blooming calcifying species. 展开更多
关键词 COCCOLITHOPHORE Pleurochrysiscarterae METABOLITES METABOLOME dimethylsulphoniopropionate(DMSP)
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A Study on Triacylglycerol Composition and the Structure of High-Oleic Rapeseed Oil 被引量:3
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作者 Mei Guan Hong Chen +4 位作者 Xinghua Xiong Xin Lu Xun Li Fenghong Huang Chunyun Guan 《Engineering》 SCIE EI 2016年第2期258-262,共5页
The composition of fatty acids in triacylglycerides (TAGs) and their position on the glycerol backbone de- termine the nutritional value of vegetable oil. In this study, gas chromatography and high-performance liqui... The composition of fatty acids in triacylglycerides (TAGs) and their position on the glycerol backbone de- termine the nutritional value of vegetable oil. In this study, gas chromatography and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) were used to analyze the compo- sition and distribution of fatty acids in TAGs of different rapeseed oils. Our results show the content of oleic acid in higb-oleic-acid rapeseed oil to be about 80%. In terms of the number of acyl carbon atoms (CN), TAGs with CN52-54 were most abundant, with a maximum concentration at CN54 (80%). The main type of TAG was oleic-oleic-oleic (OOO), accounting for 71.75%, while oleic-oleic-linoleic (OOL) accounted for ?.56%, oleic-oleic-linolenic (OOLn) accounted for 4.81%, and stearic-oleic-oleic (SO0) accounted for 4.74%. Oleic acid in high-oleic-acid rapeseed oil was distributed in the following order of preference: sn-2 〉 sn-1/3. In high-erucic-acid rapeseed oil, however, oleic acid was enriched at the sn-1/3. These data show that the content of oleic acid can be as high as about 80% in high-oleic-acid material. This finding suggests that high-oleic-acid rapeseed oil has high nutritional value. 展开更多
关键词 Brassica napus Fatty acid Triacylglycerol
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Bioactive and Some Nutritional Characteristics of Pepino (Solanum muricatum Aiton) Fruit
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作者 M. M. Ozcan D. Arslan 《Journal of Agricultural Science and Technology(B)》 2011年第1期133-137,共5页
The some physical and chemical properties values ofpepino fruit were determined. The mineral elements (AI, B, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se and Zn) of fruit were analysed by Inductively Coupled Plasma Ato... The some physical and chemical properties values ofpepino fruit were determined. The mineral elements (AI, B, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se and Zn) of fruit were analysed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Organic acid contents were analysed via HPLC equipped Ca (3,256.96 mg/kg), K (43,465.60 mg/kg), P (7,907.32 mg/kg) Na (1,496.13 mg/kg) and Mg (2,541.12 mg/kg) were established as major minerals in fruits. These results show that pepino fruit may be useful for the evaluation of dietary information in important food crops. 展开更多
关键词 PEPINO S. muricatum proximate composition organic acid HPLC minerals.
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Production of Aflatoxins from Aspergillus flavus in Liquid Medium 被引量:1
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作者 Maria Edite Bezerra da Rocha Francisco das Chagas Oliveira Freire +4 位作者 Icaro Gusmao Pinto Vieira Jose Mariados Santos Filho Fabio Erlan Feitosa Maia Maria Izabel Florindo Guedes Davide Rondina 《Journal of Life Sciences》 2013年第4期377-381,共5页
Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the pr... Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the production of aflatoxin in liquid media using strains of Aspergillus flavus obtained from peanuts marketed in the city of Fortaleza, CEo Strains of Aspergillus flavus were inoculated into a liquid medium malt extract and after 2 days inoculated into a second medium containing sucrose 5%, MgSO4·7H20 0.1%, KH2PO4 1%, ZnSO4·7H2O 0.0176 g, and cultured for 3 more days. The media were kept at room temperature ranging from 24°C to 32 °C with agitation of 130 rpm and aeration of 4.17 Llmin. Qualitative analysis was performed by thin layer chromatography and quantitatively by high performance liquid chromatography with fluorescence detection, demonstrating the production of aflatoxin B I (588 mg/L) and B2 (929 mg/L). 展开更多
关键词 PEANUT FUNGI micotoxins chromatography.
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Composition of Pig Manures and Wastewaters under the Gan Qing Fen System in China 被引量:1
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作者 R. Mendoza-Huaitalla E. Gallmann +2 位作者 K. Zheng X. J. Liu E. Hartung 《Journal of Agricultural Science and Technology(A)》 2011年第4X期514-518,共5页
A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2... A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2009. Samples were collected once a week based on the pig production cycle, namely gestation, farrowing, weaning and fattening. Analysis of nutrients and heavy metals were determined by means of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP). Total Nitrogen (TN) was determined by the Kjeldahl method. The main results showed that pig manures were characterized by high nutrients and heavy metals contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manure management system. Further, piggery wastewaters were characterized by very low concentrations of nutrients and heavy metals as result of their dilution with flushing water mainly used for cleaning the pigsties. Manure and wastewaters samples from weaning pigs contained the highest concentrations of nutrients and heavy metals that could be due to high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manures in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manures but the use of flushing water should be reduced as it can lead to further environmental pollution. 展开更多
关键词 China gan qing fen MANURE WASTEWATER pig farm.
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Alginate-Casein Microspheres as Bioactive Vehicles for Nutrients 被引量:2
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作者 何志敏 张茜青 +2 位作者 齐崴 黄仁亮 苏荣欣 《Transactions of Tianjin University》 EI CAS 2015年第5期383-391,共9页
The aim of this work was to develop an alginate-casein composite microsphere as a bioaetive vehicle for oral administration of nutrients by a simple extrusion dripping method. Riboflavin was selected as a model drug, ... The aim of this work was to develop an alginate-casein composite microsphere as a bioaetive vehicle for oral administration of nutrients by a simple extrusion dripping method. Riboflavin was selected as a model drug, and the microencapsulation efficiency was raised to 97.94% after optimizing the preparation conditions by response surface methodology. In vitro release studies showed that riboflavin was released completely from alginate-casein microspheres in simulated intestinal fluids. Meanwhile, the morphology, structure and interaction between alginate and casein were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectra. 展开更多
关键词 ALGINATE CASEIN microcncapsulation response surface methodology bioactive peptides
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The Advanced Approaches to Nutritional and Breadmaking Quality of Wheat, Barley and Rye Flour
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作者 Marcela Slukova Nikoleta Velebna Lucie Krejcirova Iva Honcu Eva Budilova 《Journal of Food Science and Engineering》 2012年第4期218-226,共9页
This work is focused on the characterization and rapid analytical determination of cereal flour quality with regard to nutritional and breadmaking quality. Starch, protein and non-starch polysaccharides are the main c... This work is focused on the characterization and rapid analytical determination of cereal flour quality with regard to nutritional and breadmaking quality. Starch, protein and non-starch polysaccharides are the main components of cereals. The content and quality of proteins and content of damaged starch is important because of the technological quality of flours. The high content of high molecular weight proteins is substantial for bread technology especially, while soluble protein fractions and non-starch polysaccharides are important for nutrition. The set of wheat, barley and rye flours and their blends were analyzed and their properties and their qualitative parameters were determined. Principal component analysis (PCA) was used on Fourier transform-infrared (FT-IR) spectra in the 1,200-800 cm1 wavenumber region and significant correlations of various nutritional and breadmaking parameters were observed. Results showed that the FT-IR spectroscopy and PCA can serve for rapid screening and classification of cereal flour quality. 展开更多
关键词 CEREALS FLOUR quality FT-IR spectroscopy PCA.
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Whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for rapid identification of bacteria cultured in liquid media 被引量:4
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作者 ZHOU Na WANG Na +5 位作者 XU Bin WANG Jie FANG JunJian DONG FangTing HE Kun YANG XiaoHong 《Science China(Life Sciences)》 SCIE CAS 2011年第1期48-53,共6页
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been used for many years to rapidly identify whole bacteria. However, no consistent methodology exists for the rapid iden... Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been used for many years to rapidly identify whole bacteria. However, no consistent methodology exists for the rapid identification of bacteria cultured in liquid media. Thus, in this study we explored the use of MALDI-TOF MS analysis for rapid identification of cells cultured in liquid media. We determined that 2,5-dihydroxybenzoic acid (50 mg mL-1, 50% acetonitrile, 0.1% trifluoroacetic acid) was the best matrix solution for MALDI-TOF MS for this type of study. Moreover, the tested strains were successfully differentiated by principal component analysis, and the main characteristics of the mass peaks for each species were found in mixed culture samples. In addition, we found that the minimum number of cells for detection was 1.8×103. In conclusion, our findings suggest that MS-based techniques can be developed as an auxiliary method for rapidly and accurately identifying bacteria cultured in liquid media. 展开更多
关键词 MALDI-TOF MS BACTERIA PCA identification
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Environmental constraints on the inter-genus variation in the scaling relationship between leaf nitrogen and phosphorus concentrations
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作者 Yanpei Guo Zhengbing Yan +3 位作者 Yi-Wei Zhang Guoyi Zhou Zongqiang Xie Zhiyao Tang 《Journal of Plant Ecology》 SCIE CSCD 2021年第4期616-627,共12页
Aims The scaling relationship between nitrogen(N)and phosphorus(P)concentrations([N]and[P],respectively)in leaves manifests plants’relative investment between the two nutrients.However,the variation in this relations... Aims The scaling relationship between nitrogen(N)and phosphorus(P)concentrations([N]and[P],respectively)in leaves manifests plants’relative investment between the two nutrients.However,the variation in this relationship among taxa as well as its causes was seldom described.Methods The analysis was based on a dataset including 2483 leaf samples from 46 genera of angiosperm woody plants from 1733 sites across China.We calculated the leaf N–P scaling exponent(βL)with an allometric equation([N]=α[P]β),for each genus,respectively.We then performed phylogenetic path analyses to test how the climate and soil niche conditions of these genera contributed to the inter-genus variation inβL.Important Findings The genera living with lower soil P availability presented a more favoured P uptake relative to N,as shown by the higherβL,suggesting a resistant trend to P limitation.Additionally,genus-wiseβL was positively correlated with soil N–P scaling exponents(β_(S)),implying that the variation in leaf nutrients is constrained by the variability in their sources from soil.Finally,climatic factors including temperature and moisture did not affectβL directly,but could have an indirect influence by mediating soil nutrients.Phylogeny did not affect the inter-genus variation inβL along environmental gradients.These results reveal that the trade-off between N and P uptake is remarkably shaped by genus niches,especially soil nutrient conditions,suggesting that theβL could be considered as a functional trait reflecting characteristics of nutrient utilization of plant taxa in response to niche differentiation. 展开更多
关键词 moisture NICHE nutrient uptake PHYLOGENY soil nitrogen phosphorus allometry soil nutrient availability temperature
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Biodegradation of Benzo[a]pyrene by Arthrobacter oxydans B4 被引量:5
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作者 PENG Hui YIN Hua +4 位作者 DENG Jun YE Jin-Shao CHEN Shuo-Na HE Bao-Yan ZHANG Na 《Pedosphere》 SCIE CAS CSCD 2012年第4期554-561,共8页
A bacterial strain, Arthrobacter oxydans (B4), capable of degrading benzo[a]pyrene (BaP) in water body, was isolated from a polycyclic aromatic hydrocarbons-contaminated site. Effects of different factors, such as... A bacterial strain, Arthrobacter oxydans (B4), capable of degrading benzo[a]pyrene (BaP) in water body, was isolated from a polycyclic aromatic hydrocarbons-contaminated site. Effects of different factors, such as reaction time, pH value, temperature and organic nutrients, on BaP biodegradation by the strain B4 were studied. After 5 d treatment, the concentration of BaP in mineral salts medium was reduced to 0.318 mg L-1, compared to the initial concentration of 1.000 mg L-1. There was a process of acid formation during the degradation with pH falling from initial 7.01 to 4.61 at 5 d, so keeping the water body under slightly alkaline condition was propitious to BaP degradation. Strain B4 efficiently degraded BaP at 20 to 37 ~C with addition of organic nutrients. The biodegradation and transformation of BaP mainly occurred on cell surfaces, and extracellular secretions played an important role in these processes. Fourier transform infrared spectroscopy and gas chromatograph-mass spectrometer analyses of metabolites showed that ring cleavage occurred in the BaP degradation process and the resulting metabolically utilizable substrates were generated as sole carbon sources for B4 growth. Furthermore, mineralization extent of metabolites was verified by determining the total organic carbon and inorganic carbon in the degradation system. 展开更多
关键词 DEGRADATION MECHANISM METABOLITES microbial transformation polycyclic aromatic hydrocarbon
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