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Coupled effects of methane monooxygenase and nitrogen source on growth and poly-β-hydroxybutyrate(PHB)production of Methylosinus trichosporium OB3b

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Journal of Environmental Sciences 2017年第2期29卷 49-57页

作者： Tingting Zhang Jiti Zhou Xiaowei Wang Yu Zhang Key Laboratory of Industrial Ecology and Environmental Engineering School of Environmental Sdence and TechnologyDalian University of TechnologyDalian 115024China

The coupled effects of nitrogen source and methane monooxygenase（MMO） on the growth and poly-β-hydroxybutyrate（PHB） accumulation capacity of methanotrophs were *** ammonia-supplied methanotrophs expressing soluble MMO（s MMO） grew at the highest rate, while N2-fixing bacteria expressing particulate MMO（p MMO） grew at the lowest rate. Further study showed that more hydroxylamine and nitrite was formed by ammonia-supplied bacteria containing p MMO, which might cause their slightly lower growth rate. The highest PHB content（51.0%） was obtained under nitrogen-limiting conditions with the inoculation of nitrate-supplied bacteria containing p MMO. Ammoniasupplied bacteria also accumulated a higher content of PHB（45.2%） with the expression of p MMO, while N2-fixing bacteria containing p MMO only showed low PHB production capacity（32.1%）. The maximal PHB contents of bacteria expressing s MMO were low, with no significant change under different nitrogen source conditions. The low MMO activity,low cell growth rate and low PHB production capacity of methanotrophs continuously cultivated with N2 with the expression of p MMO were greatly improved in the cyclic NO3-N2 cultivation regime, indicating that long-term deficiency of nitrogen sources was detrimental to the activity of methanotrophs expressing pMMO.

关键词： Methane Methanotroph PHB nitrogen source Methane monooxygenase

Improvement of Growth and Periplocin Yield of Periploca sepium Adventitious Root Cultures by Altering nitrogen source Supply

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Chinese Herbal Medicines 2011年第3期3卷 -页

作者： ZHANG Jian GAO Wen-yuan WANG Juan LI Xing-lin XIAO Pei-gen School of Traditional Chinese Materia Medica Tianjin University of Traditional Chinese MedicineTianj in 300193China

Objective To increase the ultimate yield of periplocin in Periploca sepium adventitious root cultures by a two-stage culture based on nitrogen *** Firstly,the effects of nitrogen source(NH4+-NO3-) at different ratios and different total initial nitrogen amounts on the accumulation of biomass and secondary metabolites in adventitious root cultures of *** were investigated,and growth and production media for the two-stage culture based on the above results were *** The highest biomass and periplocin content were obtained in the culture medium of 15 mmol/L total nitrogen amount with NH4+-NO3-(1:2) and 30 mmol/L total nitrogen amount with nitrate as the sole nitrogen *** adopting a fed-batch cultivation strategy,the dry weight adventitious root,periplocin content and yield were increased by 136%,108%,and 389%,respectively when compared with those of the control,reaching up to 8.13 g/L,157.15 μg/g,and 1277.63 μg/L,***,it was found that in the process of two-stage culture,the adventitious roots grew thicker significantly after they were transferred into production medium *** The ultimate yield of periplocin in *** adventitious root cultures could be significantly increased by a two-stage culture based on nitrogen source.

关键词： adventitious root nitrogen source Periploca sepium periplocin yield two-stage culture

Preliminary Study on the Responses of Three Marine Algae,Ulva pertusa(Chlorophyta),Gelidium amansii(Rhodophyta)and Sargassum enerve(Phaeophyta),to nitrogen source and Its Availability

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Journal of Ocean University of China 2004年第1期3卷 75-79页

作者： LIUDongyan AmyPickering SUNJun CollegeofMarineLifeScience OceanUniversityofChinaQingdao266003P.R.China DepartmentofBiologicalandEnvironmentalEngineering CornellUniversityIthacaNY14850USA KeyLaboratoryofMarineEcology＆EnvironmentalScience InstituteofOceanologyChineseAcademyofSciencesQingdao266071P.R.China

An experiment was designed to select economically valuable macroalga species with high nutrient uptake rates. Such species cultured on a large scale could be a potential solution to eutrophication. Three macroalgae species, Ulva pertusa (Chlorophyta), Gelidium amansii (Rhodophyta) and Sargassum enerve (Phaeophyta), were chosen for the experiment because of their economic values and availability. Control and four nitrogen concentrations were achieved by adding NH + 4 and NO - 3. The results indicate that the fresh weights of all species increase faster than that of control after 5 d culture. The fresh weight of Ulva pertusa increases fastest among the 3 species. However, different species show different responses to nitrogen source and its availability. They also show the advantage of using NH + 4 than using NO - 3. U. pertusa grows best and shows higher capability of removing nitrogen at 200 μmol L -1 , but it has lower economical value. G. amansii has higher economical value but lower capability of removing nitrogen at 200 μmol L -1 . The capability of nitrogen assimilation of S. enerve is higher than that of G. amansii at 200 μmol L -1 , but the former’s increase of fresh weight is lower than those of other two species. Then present preliminary study demonstrates that it is possible to use macroalgae as biofilters and further development of this approach could provide biologically valuable information on the source, fate, and transport of N in marine ecosystems. Caution is needed should we extrapolate these findings to natural environments.

关键词： macroalgae nitrogen source eutrophication nutrient uptaking

Influence comparison of N2 and NH3 nitrogen sources on AlN films grown by halide vapor phase epitaxy

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Chinese Physics B 2020年第7期29卷 428-432页

作者： Jing-Jing Chen Jun Huang Xu-Jun Su Mu-Tong Niu Ke Xu Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of SciencesSuzhou 215123China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Suzhou Nanowin Science and Technology Co. Ltd.Suzhou 215123China

A comparison of the nitrogen sources(N2 and NH3)influence on AlN films grown by high-temperature halide vapor phase epitaxy(HVPE)is *** x-ray rocking curves(XRCs)indicate that the full width at half maximum(FWHM)of(0002)plane for AlN films using N2 as nitrogen source is generally smaller than that using *** microscope and atomic force microscope(AFM)results show that it is presently still more difficult to control the crack and surface morphology of AlN films with thicknesses of 5-10µm using N2 as the nitrogen source compared to that using *** with one-step growth,two-step growth strategy has been proved more effective in stress control and reducing the density of threading dislocations for AlN epilayers using N2 as the nitrogen *** investigations reveal that using N2 as nitrogen source in HVPE growth of AlN is immature at present,but exhibits great potential.

关键词： aluminum nitride halide vapor phase epitaxy surface structure nitrogen source

Influence of nitrogen sources on growth and mycotoxin production by isolates of Pyrenophora tritici-repentis from wheat

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The Crop Journal 2016年第2期4卷 119-128页

作者： Noureddine Bouras Michael D.Holtz Reem Aboukhaddour Stephen E.Strelkov Department of Agricultural Food and Nutritional Science410 Agriculture/Forestry CentreUniversity of Alberta Laboratoire de Biologie des Systemes Microbiens(LBSM) Ecole Normale Superieure de KoubaAlgiersAlgeria Departement de Biologie Faculte des Sciences de la Nature et de la Vie et Sciences de la TerreUniversite de Ghardaia Field Crop Development Centre Alberta Agriculture and Food

The fungus Pyrenophora tritici-repentis(Died.) Drechs. infects the leaves and kernels of wheat,causing tan spot and red smudge, respectively. Isolates of P. tritici-repentis have been reported to be both phytopathogenic and mycotoxigenic. This research investigates the influence of nitrogen sources on growth and production of mycotoxins by eight different isolates of P. tritici-repentis. A synthetic agar medium(SAM) was used with different nitrogen sources, both inorganic [(NH4Cl, NH4NO3and(NH4)2SO4)] and organic(L-alanine, L-histidine, and L-lysine), at a concentration of 37.5 mmol L-1. Individual isolates exhibited different growth rates that varied according to the nitrogen source added to the medium. The choice of nitrogen source also had a major effect on production of the mycotoxins emodin, catenarin and islandicin. The highest concentrations of emodin, 54.40 ± 4.46 μg g-1, 43.07 ± 23.39 μg g-1and28.91 ± 4.64 μg g-1of growth medium, were produced on the complex medium(V8-potato dextrose agar) by the isolates Alg-H2, 331-2 and TS93-71 B, respectively. A relatively high concentration of emodin also was produced by isolates Az35-5(28.29 ± 4.71 μg g-1of medium)and TS93-71B(27.03 ± 4.09 μg g-1of medium) on synthetic medium supplemented with L-alanine. The highest concentrations of catenarin(174.54 ± 14.46 μg g-1and 104.87 ±6.13 μg g-1of medium) were recorded for isolates TS93-71 B and Alg-H2 on synthetic medium supplemented with L-alanine and NH4 Cl, respectively. The highest concentration of islandicin(4.64 ± 0.36 μg g-1medium) was observed for isolate 331-2 in the presence of L-lysine. There was not a close relationship between mycelial growth and mycotoxin production by the fungal isolates. This is the first report on the influence of nitrogen sources on the production of mycotoxins by P. tritici-repentis.

关键词： Catenarin Emodin Islandicin nitrogen source Tan spot Triticum aestivum

Studies on optimization of nitrogen sources for astaxanthin production by Phaffia rhodozyma

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第5期8卷 365-370页

作者： NI Hui CHEN Qi-he RUAN Hui YANG Yuan-fan LI Li-jun WU Guang-bin Hid Yang HE Guo-qing School of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 China School of Bioengineering Jimei University Xiamen 361021 China School of Information and Engineering Technique Sichuan Agriculthral University Ya ＇an 625014 China

Fermentation of Phaffia rhodozyma is a major method for producing astaxanthin, an important pigment with industrial and pharmaceutical application. To improve astaxanthin productivity, single factor and mixture design experiments were used to investigate the effects of nitrogen source on Phaffia rhodozyma cultivation and astaxanthin production. Results of single factor experiments showed nitrogen source could significantly affect P. rhodozyma cultivation with respect to carbon source utilization, yeast growth and astaxanthin accumulation. Further studies of mixture design experiments using (NH4)2SO4, KNO3 and beef extract as nitrogen sources indicated that the proportion of three nitrogen sources was very important to astaxanthin production. Validation experiments showed that the optimal nitrogen source was composed of 0.28 g/L (NH4)2SO4, 0.49 g/L KNO3 and 1.19 g/L beef extract. The kinetic characteristics of batch cultivation were investigated in a 5-L pH-stat fermentor. The maximum amount of biomass and highest astaxanthin yield in terms of volume and in terms of biomass were 7.71 mg/L and 1.00 mg/g, respectively.

关键词： Phaffia rhodozyma Astaxanthin nitrogen source Optimization

Nutrient Value of Protein from Pleurotus tuber-regium Sclerotia Grown with Different nitrogen sources

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食用菌学报 2006年第3期 52-54页

作者： LEI Jin-gui~ 1* , WENG Bo-qi~2, JIANG Zhi-he~1, TANG Xiang-qiu~1, WANG Yi-xiang~2 ~1 The Development and Application Research Center of Edible Fungi,Fujian Academy of Agricultural Sciences, Fuzhou 350013, China ~2 Institute of Agricultural Zoology Project, Academy of Agricultural Sciences, Fuzhou 350013, China

Protein from P. tuber-regium sclerotia cultivated using four different nitrogen sources [urea, cattle dung, （NH4）2SO4and wheat bran] was assessed in terms of six nutritive quality indices—Amino Acid Score （AAS）, Chemical Score （CS）,Essential Amino Acid Index （EAAI）,Biological Value （BV）, Nutritional Index （NI） and Amino Acid Ratio Coefficient Score （AARCS）. Protein from sclerotia cultivated with urea as the nitrogen source had a superior overall nutrient value and was ranked highest in terms of all six indices. Protein from sclerotia grown with wheat bran was ranked second in the case of three protein quality indices （AAS, CS and NI） and third for the remaining three indices （EAAI, BV and AARCS）. Protein from sclerotia grown with （NH4）2SO4was ranked second in terms of three indices （EAAI,BV and AARCS） and third for the remaining three indices. Protein from sclerotia grown with cattle dung had the lowest nutrient value and was ranked lowest in terms of all six quality indices.

关键词： nitrogen source Pleurotus tuber-regium Sclerotia Protein quality Nutritive value

Production of polyhydroxybutyrate by the marine photosynthetic bacterium Rhodovulum sulfidophilum P5

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Chinese Journal of Oceanology and Limnology 2012年第4期30卷 620-626页

作者：才金玲魏莹赵宇鹏潘光华王广策 Tianjin Key Laboratory of Marine Resources and Chemistry College of Marine Science and EngineeringTianjin University of Science and Technology Institute of Oceanology Chinese Academy of Sciences

The effects of different NaCl concentrations, nitrogen sources, carbon sources, and carbon to nitrogen molar ratios on biomass accumulation and polyhydroxybutyrate （PHB） production were studied in batch cultures of the marine photosynthetic bacterium Rhodovulum sulfidophilum P5 under aerobic-dark conditions. The results show that the accumulation of PHB in strain P5 is a growth-associated process. Strain P5 had maximum biomass and PHB accumulation at 2%-3% NaCl, suggesting that the bacterium can maintain growth and potentially produce PHB at natural seawater salinity. In the nitrogen source test, the maximum biomass accumulation （8.10±0.09 g/L） and PHB production （1.11±0.13 g/L and 14.62%±2.25% of the cell dry weight） were observed when peptone and ammonium chloride were used as the sole nitrogen source. NH^-N was better for PHB production than other nitrogen sources. In the carbon source test, the maximum biomass concentration （7.65±0.05 g/L） was obtained with malic acid as the sole carbon source, whereas the maximum yield of PHB （5.03±0.18 g/L and 66.93%± 1.69% of the cell dry weight） was obtained with sodium pyruvate as the sole carbon source. In the carbon to nitrogen ratios test, sodium pyruvate and ammonium chloride were selected as the carbon and nitrogen sources, respectively. The best carbon to nitrogen molar ratio for biomass accumulation （8.77±0.58 g/L） and PHB production （6.07±0.25 g/L and 69.25%±2.05% of the cell dry weight） was 25. The results provide valuable data on the production of PHB by R. sulfidophilum P5 and further studies are on-going for best cell growth and PHB yield.

关键词： polyhydroxybutyrate Rhodovulum sulfidophilum nitrogen source carbon source carbon tonitrogen molar ratio

Isolation and Characterization of Methanethiol-Producing Bacteria from Agricultural Soils

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Pedosphere 2017年第6期27卷 1083-1091页

作者： LIU Hui SHI Chengfei WU Ting JIA Qina ZHAO Juan WANG Xinming College of Environmental Science and Engineering Anhui Normal University State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences

Methanethiol(MT) produced from terrestrial soils can have important effects on atmospheric chemistry and ecosystem-level processes, and it originates mainly from the metabolism of sulfur-containing amino acids by *** producing bacteria(MPB) were enriched and isolated from agricultural soils in a modified basal medium containing methionine(Met) as the sole carbon *** isolates were identified as Bacillus ***-R1, WH-R2, and WH-R3; Arthrobacter ***-W3; and Delftia ***-R4 based on cell morphology, physiological and biochemical characteristics, and 16 S r RNA sequence *** ***-R4 was identified as a novel strain producing MT using Met as a precursor, and it had the most active MT-producing potential, with the production of MT being 21.8 μg at 30℃ and pH *** MT production was observed at 35℃ and pH6.0, with 51.3% of sulfur content in Met being converted into *** these conditions, MT production changed according to the supply of both carbon and nitrogen *** addition of 2 g L^(-1) each of starch, sucrose, urea, and potassium nitrate promoted MT production by more than 10%, whereas addition of 2 g L^(-1) each of ammonia sulfate and peptone decreased MT production by16% and 87%, *** is the first study to report MT production by Delftia ***-R4, providing useful information for the microbial mechanism of MT production from agricultural *** findings also contribute to improving our knowledge of the function of Delftia ***-R4.

关键词： Arthrobacter sp. Bacillus sp. carbon source Delftia sp. methionine nitrogen source volatile organic sulfur compounds