共查询到20条相似文献,搜索用时 15 毫秒
1.
Sushma Deepthi Arli U. B. Trivedi K. C. Patel 《World journal of microbiology & biotechnology》2011,27(6):1415-1422
Cellulomonas flavigena UNP3, a natural isolate from vegetable oil contaminated soil sample has been studied for growth associated exopolysaccharide
(EPS) production during growth on glucose, groundnut oil and naphthalene. The EPS showed matrix formation surrounding the
cells during scanning electron microscopy. Cell surface hydrophobicity and emulsifying activity studies confirmed the role
of EPS as bioemulsifier. Emulsifying activity was found to increase with time (0.2 U/mg for 10 min to 0.27 U/mg for 30 min).
Emulsification index, E24 value increased with the increase in EPS concentration. Degradation of polyaromatic hydrocarbons was confirmed using gas
chromatography analysis. FTIR analysis showed presence of characteristic absorbance at 895.10 cm−1 for β-configuration of glucan. NMR studies also revealed EPS produced by C. flavigena UNP3 as a linear β-1, 3-d-glucan, and a curdlan like polysaccharide. 相似文献
2.
Sarkar J Ray S Chattopadhyay D Laskar A Acharya K 《Bioprocess and biosystems engineering》2012,35(4):637-643
The development of an eco-friendly and reliable process for the synthesis of gold nanomaterials (AuNPs) using microorganisms
is gaining importance in the field of nanotechnology. In the present study, AuNPs have been synthesized by bio-reduction of
chloroauric acid (HAuCl4) using the fungal culture filtrate (FCF) of Alternaria alternata. The synthesis of the AuNPs was monitored by UV–visible spectroscopy. The particles thereby obtained were characterized by
UV, dynamic light scattering (DLS), X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis, Fourier transform infrared
(FTIR) spectroscopy, atomic force microscopy (AFM) and transmission electron microscopy (TEM). Energy-dispersive X-ray study
revealed the presence of gold in the nanoparticles. Fourier transform infrared spectroscopy confirmed the presence of a protein
shell outside the nanoparticles which in turn also support their stabilization. Treatment of the fungal culture filtrate with
aqueous Au+ ions produced AuNPs with an average particle size of 12 ± 5 nm. This proposed mechanistic principal might serve as a set
of design rule for the synthesis of nanostructures with desired architecture and can be amenable for the large scale commercial
production and technical applications. 相似文献
3.
Rau U Kuenz A Wray V Nimtz M Wrenger J Cicek H 《Applied microbiology and biotechnology》2009,81(5):827-837
Trametes versicolor ATCC 200801 secretes 4.1 g L−1 of exopolysaccharide (EPS) when synthetic minimal medium and low-shear bioreactor cultivation technique are used. Structural
and compositional analyses by thin layer chromatography, gas chromatography–mass spectrometry, electrospray ionization tandem
mass spectrometry, and nuclear magnetic resonance spectroscopy yielded predominantly glucose and small amounts of galactose,
mannose, arabinose, and xylose. The main EPS is composed of β-1,3/β-1,6-linked d-glucose molecules which is identical with Schizophyllan but does not possess a triple helical arrangement as secondary structure.
Two molar mass fractions were detected by size exclusion chromatography yielding weight-average molecular weights of 4,100
and 2.6 kDa. Protein content varies between 2–3.6% (w/w). The exopolysaccharide is different in the nature of the glycosidic linkage, composition of monosaccharides, protein content,
and weight-average molecular weight compared to the well-known polysaccharopeptide (PSP) and polysaccharopeptide Krestin (PSK). 相似文献
4.
Ulrich Metzger Ulrich Lankes Kai Fischpera Fritz H. Frimmel 《Applied microbiology and biotechnology》2009,85(1):197-206
Extracellular polymeric substances were extracted from the bacterial strain Pseudomonas putida and the fungal species Aureobasidium pullulans using three different methods (formaldehyde–NaOH, ethylenediaminetetraacetic acid (EDTA) and cation-exchange-resin). The
composition of the extracellular polymeric substances (EPS) was analysed by biochemical and high-resolution solid state 13C nuclear magnetic resonance (NMR) spectroscopic methods. The EPS yield was strongly dependent on the extraction method, with
the formaldehyde–NaOH method showing the best extraction efficiency. The NMR method revealed that when using the EDTA extraction
method, about 40% of the EDTA accumulated in the EPS and that was responsible for the apparent high extraction yields. EPS
protein content determined by the NMR method was up to 30% higher than the protein content determined using the biochemical
(Lowry) method for P. putida and for A. pullulans. The average protein carbon content determined by the NMR method was approximately 70% of the total carbon content. NMR results
could be supported by elemental analysis, which showed a high nitrogen content (~10%) in the EPS. The carbohydrate carbon
content detected with both methods in the cell aggregates and the EPS was approximately 20% in each. In this study, quantitative
13C cross-polarisation magic angle spinning NMR spectroscopy was conducted on unlabeled cell strains, and EPS and could be used
to quantify protein and carbohydrate of different samples. 相似文献
5.
Lili Wang Fang Ma Yuanyuan Qu Dezhi Sun Ang Li Jingbo Guo Bing Yu 《World journal of microbiology & biotechnology》2011,27(11):2559-2565
A compound bioflocculant CBF-F26, produced by mixed culture of Rhizobium radiobacter F2 and Bacillus sphaeicus F6, was investigated with regard to its physicochemical and flocculating properties. It was identified as a polysaccharide
bioflocculant composed of rhamnose, mannose, glucose, and galactose, respectively, in a 1.3: 2.1: 10.0: 1.0 molar ratio. The
average molecular weight was determined as 4.79 × 105 Da by gel-permeation chromatography. Infrared spectrum and X-ray photoelectron spectroscopy revealed the presence of carboxyl,
hydroxyl and amino groups in its structure. Thermostability test suggested that CBF-F26 was thermostable and high flocculating
activity was maintained. Thermogravimetric property, intrinsic viscosity and surface morphology of CBF-F26 were also studied.
CBF-F26 was effective under neutral and weak alkaline conditions (pH 7.0–9.0), and flocculating activities of higher than
90% were obtained in the concentration range of 8–24 mg l−1 at pH 8.0. The flocculation could be stimulated by cations Ca2+, Zn2+, Fe2+, Al3+, and Fe3+. In addition, the probable flocculation mechanisms were proposed. 相似文献
6.
Elin Säwén Eine Huttunen Xue Zhang Zhennai Yang Göran Widmalm 《Journal of biomolecular NMR》2010,47(2):125-134
The use of lactic acid bacteria in fermentation of milk results in favorable physical and rheological properties due to in
situ exopolysaccharide (EPS) production. The EPS from S. thermophilus ST1 produces highly viscous aqueous solutions and its structure has been investigated by NMR spectroscopy. Notably, all aspects
of the elucidation of its primary structure including component analysis and absolute configuration of the constituent monosaccharides
were carried out by NMR spectroscopy. An array of techniques was utilized including, inter alia, PANSY and NOESY-HSQC TILT
experiments. The EPS is composed of hexasaccharide repeating units with the following structure: → 3)[α-d-Glcp-(1 → 4)]-β-d-Galp-(1 → 4)-β-d-Glcp-(1 → 4)[β-d-Galf-(1 → 6)]-β-d-Glcp-(1 → 6)-β-d-Glcp-(1 →, in which the residues in square brackets are terminal groups substituting backbone sugar residues that consequently
are branch-points in the repeating unit of the polymer. Thus, the EPS consists of a backbone of four sugar residues with two
terminal sugar residues making up two side-chains of the repeating unit. The molecular mass of the polymer was determined
using translational diffusion experiments which resulted in Mw = 62 kDa, corresponding to 64 repeating units in the EPS. 相似文献
7.
S. V. N. Vijayendra G. Palanivel S. Mahadevamma R. N. Tharanathan 《Archives of microbiology》2009,191(4):303-310
A heterofermentative Lactobacillus sp. CFR-2182 was isolated from dahi samples and it was found to produce 8.0 and 20.5 g/L heteropolysaccharide (HePS) in EPS medium (a simplified synthetic medium)
and modified MRS broth, respectively, after 72 h at 30°C. The total carbohydrate, reducing sugar and moisture contents of
the purified HePS were 74, 10.6 and 2 g, respectively, per 100 g on dry weight basis. The HePS produced in EPS medium had
glucose and mannose in 17:1 ratio. The HePS was non-gelling and non-film forming type. It was completely soluble in water
and 1 N sodium hydroxide solution. Gel permeation chromatography and HPLC analysis indicated considerable heterogeneity of
the HePS, having three fractions with molecular weights ranging from 3.3 × 104 to 1.32 × 106 Da. The enzymatic hydrolysis of the HePS with pullulanase and α-amylase [with α(1→4) linkage] indicated the presence of α(1→6)
and traces of α(1→4) linkages, respectively. NMR analysis of the EPS revealed unique chemical shifts. 相似文献
8.
Larry V. Padilla Maria Lourdes San Diego-McGlone Rhodora V. Azanza 《Journal of applied phycology》2010,22(6):761-768
Harmful algal bloom occurrences worldwide have prompted the testing and use of methods to control and mitigate their detrimental
effects. This study investigates the potential of Philippine clay minerals to physically remove phytoplankton cells under
laboratory conditions. Ball clay had the highest removal efficiency (∼95%) for Pyrodinium bahamense (paralytic shellfish poisoning causative organism) cells. A slight decrease in the efficiency by 10–20% was seen when culture
volume was increased from 50 mL to 1 L. Removal efficiency was reduced to ∼95% when water motion was introduced. Removal of
other phytoplankton species (Gymnodinium sanguineum, Amphidinium carterae, Pyrophacus horologium, Chatonella marina, and Alexandrium sp.) using ball clay was less efficient (<70%). Cell removal efficiencies differed with phytoplankton species belonging to
the same taxonomic group. Possible mechanisms for cell removal are described. 相似文献
9.
Chu-Ting Liu I-Ting Hsu Cheng-Chun Chou Pei-Ren Lo Roch-Chui Yu 《World journal of microbiology & biotechnology》2009,25(5):883-890
In the present study, the production of exopolysaccharides (EPS) by 13 strains of Lactobacillus and 6 strains of Bifidobacterium in a chemical defined medium (CDM) supplemented with 30 g lactose/l was first compared. The highest EPS production of the
Lactobacillus strains was found in L. salivarius BCRC 14759 while among the Bifidobacterium strains examined, B. bifidum BCRC 14615 showed the highest EPS production. Analyzes of the effect of lactose concentration and cultivation temperature
on EPS production revealed that L. salivarius produced the highest amount of EPS (45.3 mg/l) in CDM supplemented with 5 g lactose/l at 40°C while B. bifidum produced the highest EPS (17.0 mg/l) in CDM supplemented with 40 g lactose/l at 35°C. α-Phosphoglucomutase, UDP-glucose pyrophosphorylase
and UDP-galactose-4-epimerase exhibited a markedly notable activity compared with other enzymes examined in the cell extract
of both test organisms. This indicates their possible involvement in the biosynthesis of EPS. 相似文献
10.
Jindal N. Singh D. P. Khattar J. I. S. 《World journal of microbiology & biotechnology》2011,27(9):2139-2146
Exopolysaccharides of the cyanobacterium Oscillatoria formosa have been physico-chemically characterized and kinetics of their production studied. The organism produced 334.8 μg EPS per
ml culture in 24 days with the maximum rate of production obtained during initial days of growth. HPLC analysis of the EPS
hydrolysate revealed that besides three unidentified sugars, EPS contained ribose, mannose, and galacturonic acid. FT-IR spectrum
of EPS revealed the presence of methyl, carboxyl and C–N groups. Elemental analysis indicated the presence of 4.7% nitrogen
in EPS. The organism produced 75.6% more EPS when incubated at 35°C compared to cultures at 28°C. Under varied nutritional
conditions, though the growth of the organism was less yet it produced enhanced amounts of EPS. Aqueous dispersions of EPS
showed non-Newtonian, pseudoplastic behaviour. The viscosity of the aqueous solution of EPS was quite stable over a wide range
of pH and temperature but it was observed to be affected by CaCl2. 相似文献
11.
Sorption of Cu(II) and Cd(II) by extracellular polymeric substances (EPS) from Aspergillus fumigatus
Yurong Yin Yongyou Hu Fen Xiong 《International biodeterioration & biodegradation》2011,65(7):1012-1018
Sorption of Cu(II) and Cd(II) onto the extracellular polymeric substances (EPS) produced by Aspergillus fumigatus was investigated for the initial pH of the solution, EPS concentrations, contact time, NaCl concentration, initial metal ion concentration and the presence of other ions in the solution. The results showed that the adsorption of metal ions was significantly affected by pH, EPS concentrations, initial metal concentration, NaCl concentration and co-ions. The sorption of Cu(II) and Cd(II) increased with increasing pH and initial metal ion concentration but decreased with an increase in the NaCl concentration. The maximum sorption capacities of A. fumigatus EPS calculated from the Langmuir model were 40 mg g−1 EPS and 85.5 mg g−1 EPS for Cu(II) and Cd(II), respectively. The binary metal sorption experiments showed a selective metal binding affinity in the order of Cu(II) > Pb(II) > Cd(II). Both the Freundlich and Langmuir adsorption models described the sorption of Cu(II) and Cd(II) by the EPS of A. fumigatus adequately. Fourier transform infrared spectroscopy (FTIR) analysis revealed that carboxyl, amide and hydroxyl functional groups were mainly correlated with the sorption of Cu(II) and Cd(II). Energy dispersive X-ray (EDX) system analysis revealed that the ion-exchange was an important mechanism involved in the Cu(II) and Cd(II) sorption process taking place on EPS. 相似文献
12.
The aim of the study is to examine thermal behavior of water within reticulated structure of bacterial cellulose (BC) films
by sub-ambient differential scanning calorimetry (DSC). BC films with different carbon source, either manitol (BC (a)) or
glycerol (BC (b)), were produced by Acetobacter xylinum using Hestrin and Shramm culture medium under static condition at 30 ± 0.2°C for 3 days. BC samples were characterized by
electron scanning microscopy and X-ray diffraction spectroscopy. The pore analysis was done by B.H.J. nitrogen adsorption.
The pre-treated with 100% relative humidity, at 30.0 ± 0.2°C for 7 days samples were subjected to a between 25 and −150°C-cooling–heating
cycle of DSC at 5.00°C/min rate. The pre-treated samples were also hydrated by adding 1 μl of water and thermally run with
identical conditions. It is observed that cellulose fibrils of BC (a) were thinner and reticulated to form slightly smaller
porosity than those of BC (b). They exhibited slightly but non-significantly different crystalline features. The freezable
bound water behaved as a water confinement within pores rather than a solvent of polymer which is possible to use thermoporosimetry
based on Gibb–Thomson equation to approach pore structure of BC. In comparison with nitrogen adsorption, it was found that
thermoporosimetry underestimated the BC porosity, i.e., the mean diameters of 23.0 nm vs. 27.8 nm and 27.9 nm vs. 33.9 nm for BC (a) and BC (b), respectively, by thermoporosimetry vs. B.H.J. nitrogen adsorption. It may be due to large non-freezable water fraction interacting with cellulose, and the validity
of pore range based on thermodynamic assumptions of Gibb–Thomson theory. 相似文献
13.
Wei Dong Li Ning Wei-dong Lu Cui-cui Li Rui-peng Chen Xiao-ning Jia Lin Wang Li-zhong Guo 《World journal of microbiology & biotechnology》2009,25(4):633-638
The tumor-inhibitory and liver-protective effects of crude extracellular polysaccharides (EPS) extracted from the liquid mycelial
culture of the mushroom Phellinus igniarius were studied in mice. The mice were injected with murine sarcoma S180 and murine hepatoma H22. Crude EPS at 100, 200, 400 mg kg−1 body weight was administered to EPS groups each day in the twelve consecutive days. The result showed that EPS 200 mg kg−1 body weight significantly inhibited S180 and H22 at 65.0 and 46.3%, respectively. Moreover, EPS could not only keep the numbers
of WBC, RBC, PLT and the concentration of HGB in a normal range, but also normalize the activities of AST, ALT and ALP. For
example, in EPS-treated mice, AST significantly reduced with the percentage of A/G reverse in S180 (P < 0.05) and H22 (P < 0.01) when the mice took EPS 200 mg kg−1 body weight. In conclusion, it was remarkable that P. igniarius EPS exhibited antitumor activity related to dosage and protected liver function by sustaining the blood routine as well as
keeping the blood biochemical indexes normal. 相似文献
14.
T. M. Fahima Azira A. A. Nursolehah Y. Norhayati M. I. A. Majid A. A. Amirul 《World journal of microbiology & biotechnology》2011,27(10):2287-2295
A locally isolated Gram-negative bacterium, Cupriavidus sp. USMAA2-4 was found capable of producing terpolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-3HV-co-4HB)] using γ-butyrolactone or 1,4-butanediol with either valeric acid or 1-pentanol as the carbon source. The present of
3HB, 3HV and 4HB monomers were confirmed by gas chromatography (GC) and nuclear magnetic resonance (NMR) analysis. PHA concentration
of 1.9 g/l was the highest value obtained using the combination of 1,4-butanediol and 1-pentanol through one-step cultivation
process. PHA concentration obtained through two-step cultivation process was higher for all the combinations and the highest
value achieved was 2.5 g/l using γ-butyrolactone and 1-pentanol as carbon source. Various molar fractions of 4HB and 3HV ranging
from 6 to 14 mol% and 39 to 87 mol%, respectively were produced through two-step cultivation process by manipulating the concentration
of γ-butyrolactone. As the culture aeration was reduced, the molar fraction of 3HV and 4HB increased from 40 to 67 mol% and
10 to 24 mol%, respectively while the dry cell weight and PHA content decreased. The terpolymer produced was characterized
using gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). The number-average molecular weight
(M
n) and the melting temperature (T
m)) of the terpolymer were in the range of 177–484 kDa and 160–164°C, respectively. 相似文献
15.
Molecular genetic fingerprints of nine Curcuma species from Northeast India were developed using PCR-based markers. The aim involves elucidating there intra- and inter-specific
genetic diversity important for utilization, management, and conservation. Twelve random amplified polymorphic DNA (RAPD),
19 Inter simple sequence repeats (ISSRs), and four amplified fragment length polymorphism (AFLP) primers produced 266 polymorphic
fragments. ISSR confirmed maximum polymorphism of 98.55% whereas RAPD and AFLP showed 93.22 and 97.27%, respectively. Marker
index and polymorphic information content varied in the range of 8.64–48.1, 19.75–48.14, and 25–28 and 0.17–0.48, 0.19–0.48,
and 0.25–0.29 for RAPD, ISSR, and AFLP markers, respectively. The average value of number of observed alleles, number of effective
alleles, mean Nei’s gene diversity, and Shannon’s information index were 1.93–1.98, 1.37–1.62, 0.23–0.36, and 0.38–0.50, respectively,
for three DNA markers used. Dendrograms based on three molecular data using unweighted pair group method with arithmetic mean
(UPGMA) was congruent and classified the Curcuma species into two major clusters. Cophenetic correlation coefficient between dendrogram and original similarity matrix were
significant for RAPD (r = 0.96), ISSR (r = 0.94), and AFLP (r = 0.97). Clustering was further supported by principle coordinate analysis. High genetic polymorphism documented is significant
for conservation and further improvement of Curcuma species. 相似文献
16.
González DM Lara RH Alvarado KN Valdez-Pérez D Navarro-Contreras HR Cruz R García-Meza JV 《Applied microbiology and biotechnology》2012,93(2):763-775
We have applied epifluorescence principles, atomic force microscopy, and Raman studies to the analysis of the colonization
process of pyrite (FeS2) by sulfuroxidizing bacteria Acidithiobacillus thiooxidans after 1, 15, 24, and 72 h. For the stages examined, we present results comprising the evolution of biofilms, speciation of
Sn2−/S0 species, adhesion forces of attached cells, production and secretion of extracellular polymeric substances (EPS), and its
biochemical composition. After 1 h, highly dispersed attached cells in the surface of the mineral were observed. The results
suggest initial non-covalent, weak interactions (e.g., van der Waal’s, hydrophobic interactions), mediating an irreversible
binding mechanism to electrooxidized massive pyrite electrode (eMPE), wherein the initial production of EPS by individual
cells is determinant. The mineral surface reached its maximum cell cover between 15 to 24 h. Longer biooxidation times resulted
in the progressive biofilm reduction on the mineral surface. Quantification of attached cell adhesion forces indicated a strong
initial mechanism (8.4 nN), whereas subsequent stages of mineral colonization indicated stability of biofilms and of the adhesion
force to an average of 4.2 nN. A variable EPS (polysaccharides, lipids, and proteins) secretion at all stages was found; thus,
different architectural conformation of the biofilms was observed during 120 h. The main EPS produced were lipopolysaccharides
which may increase the hydrophobicity of A. thiooxidans biofilms. The highest amount of lipopolysaccharides occurred between 15–72 h. In contrast with abiotic surfaces, the progressive
depletion of Sn2−/S0 was observed on biotic eMPE surfaces, indicating consumption of surface sulfur species. All observations indicated a dynamic
biooxidation mechanism of pyrite by A. thiooxidans, where the biofilms stability and composition seems to occur independently from surface sulfur species depletion. 相似文献
17.
The influencing factors of extracellular polysaccharide (EPS) produced from a strain of lactic acid bacteria (LAB L15) were
studied by using the phenol-H2SO4 method. It was demonstrated that the strain produced EPS at the most amount when it was incubated for 40–48 h and when the
pH value was 4 under 30°C. Glucose was the most suitable carbon source for LAB-producing EPS. The rough EPS was obtained from
L15 culture after centrifugation, dialysis, deprotein, decoloration, and ethanol-precipitation. The sample was at least composed
of two polysaccharides that were completely different in molecular weight and the amount. The purified EPS was passed through
the SephadexG-200 column and it showed that it was a sample purified by thin layer chromatography.
__________
Translated from Microbiology, 2005, 32(4): 85–90 [译自: 微生物学通报, 2005, 32(4): 85–90] 相似文献
18.
Al-Alawi AA Al-Marhubi IM Al-Belushi MS Soussi B 《Marine biotechnology (New York, N.Y.)》2011,13(5):893-899
Carrageenophyte red seaweed from Oman, Hypnea bryoides, extracted using three different processes: an aqueous, a mild alkaline, and a more vigorous alkaline extraction was investigated.
The resulting extract precipitated by alcohol was subject to chemical and rheological measurements. The total carbohydrate
[ranged from 36.78 to 41.65 g/100 g], and ash [39.04 to 43.11 g/100 g] were the most abundant components in H. bryoides and contrary to the two, lipid content was found at a minimum [ranging from 2.95 to 3.38 g/100 g]. Alkali treatment with
NaOH allowed complete conversion of kappa (κ) carrageenan form as detected by FTIR analysis. Total yield by alkali treatments
gave higher yields (33%) compared with aqueous treatments (12%). However, subsequent aqueous treatment produced mixed carrageenan
(μ and κ) with higher molecular weight compared with the alkali treatments which produced single carrageenan form (κ) with
molecular weight of 4.1 × 105 Da. The effects of thermal history on gel–sol and sol–gel transition were investigated by differential scanning calorimeter
(DSC) and rheology on a pure sample and 1.5% κ-carrageenan mixture added with 30 mM KCl. Transition temperatures from DSC
and rheology showed comparable results and were in good agreement with those previously reported. 相似文献
19.
Exopolysaccharide (EPS) production was compared among three strains of lactobacilli. Lactobacillus rhamnosus strain 9595M can be classified among the highest EPS-producing strains of lactic acid bacteria reported to date with a maximum
EPS production of 1275 mg L−1. Under controlled pH, no significant differences in the quantity of EPS produced could be detected between carbon source
(glucose or lactose) or fermentation temperature (32 or 37°C). In milk, strains ATCC 9595M and R produced more than 280 mg L−1 EPS whereas strain Type V produced less than 80 mg L−1 EPS. Journal of Industrial Microbiology & Biotechnology (2000) 24, 251–255.
Received 10 September 1999/ Accepted in revised form 22 December 1999 相似文献
20.
In this study, the characteristics of extracellular polymeric substance (EPS) fractions of biofilm during the process of establishing
a partial nitrification under salt stress were analyzed in terms of concentrations, molecular weight distribution, and three-dimensional
excitation–emission matrix (EEM) fluorescence spectroscopy. A partial nitrification was formed successfully with a salinity
of 1%. Results indicated that the amount of total EPS increased from 54.2 mg g−1 VSS−1 on day 1 to 99.6 mg g−1 VSS−1 on day 55 due to the NaCl concentration changed from 0 to 10.0 g L−1 in a biofilm reactor. The changes of loosely bound EPS (LB-EPS) compounds under different salt concentrations appeared to
be more significant than those of the tightly bound EPS. A clear release of polysaccharides in the LB-EPS fraction was detected
during the enhancement of salinity. This was considered as a protective response of bacteria to the salinity. Three fluorescence
peaks were identified in the EEM fluorescence spectra of the EPS fraction samples. Two peaks were assigned to the protein-like
fluorophores, and the third peak was located at the excitation/emission wavelengths of 275 nm/425–435 nm of the spectra of
EPS fractions till the salinity maintained constant at 1%. This information is valuable for understanding the characteristics
of EPS isolated from biomass in a saline nitrogen removal system. 相似文献