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1.
Biosorption is an eco-friendly and cost-effective method for treating the dye house effluents. Aspergillus niger and Trichoderma sp. were cultivated in bulk and biomasses used as biosorbents for the biosorption of an azo dye Orange G. Batch biosorption
studies were performed for the removal of Orange G from aqueous solutions by varying the parameters like initial aqueous phase
pH, biomass dosage, and initial dye concentration. It was found that the maximum biosorption was occurred at pH 2. Experimental
data were analyzed by model equations such as Langmuir and Freundlich isotherms, and it was found that both the isotherm models
best fitted the adsorption data. The monolayer saturation capacity was 0.48 mg/g for Aspergillus niger and 0.45 mg/g for Trichoderma sp. biomasses. The biosorption kinetic data were tested with pseudo first-order and pseudo second-order rate equations, and
it was found that the pseudo second-order model fitted the data well for both the biomasses. The rate constant for the pseudo
second-order model was found to be 10–0.8 (g/mg min−1) for Aspergillus niger and 8–0.4 (g/mg min−1) for Trichoderma sp. by varying the initial dye concentrations from 5 to 25 mg/l. It was found that the biomass obtained from Aspergillus niger was a better biosorbent for the biosorption of Orange G dye when compared to Trichoderma sp. 相似文献
2.
Sang Eun Oh Sedky H. A. Hassan Jin Ho Joo 《World journal of microbiology & biotechnology》2009,25(10):1771-1778
Biosorptive capacity of Pb(II), Cd(II) and Cu(II) by lyophilized cells of Pseudomonas stutzeri was investigated based on Langmuir and Freundlich isotherms. Biosorptive capacity for Pb(II), Cd(II) and Cu(II) decreased
with an increase of metal concentration, reaching 142, 43.5 and 36.2 mg/g at initial concentration of 300 mg/l, respectively.
Biosorption capacity for metal ions increased with increasing pH. The optimum pH for biosorption rate of Cd(II) and Cu(II)
were 5.0, and 6.0 for Pb(II) biosorption. The experimental data showed a better fit with the Langmuir model over the Freundlich
model for metal ions throughout the range of initial concentrations. The maximum sorptive capacity (q
max) obtained from the Langmuir equation for Pb(II), Cd(II) and Cu(II) were 153.3 (r
2
= 0.998), 43.86 (r
2
= 0.995), and 33.16 (r
2
= 0.997) for metal ions, respectively. The selectivity order for metal ions towards the biomass of P. stutzeri was Pb(II) > Cd(II) > Cu(II) for a given initial metal ions concentration. The interactions between heavy metals and functional
groups on the cell wall surface of bacterial biomass were confirmed by FTIR analysis. The results of this study indicate the
possible removal of heavy metals from the environment by using lyophilized cells of P. stutzeri. 相似文献
3.
Mounir R Durieux A Bodo E Allard C Simon JP Achbani EH El-Jaafari S Douira A Jijakli MH 《Biotechnology letters》2007,29(4):553-559
Aureobasidium pullulans (de Bary) Arnaud (Ach 1-1) was grown in a glucose fed-batch fermentor to 106 g dry wt l−1 in 48 h. The cells were dried in a fluidized bed dryer with a final viability of 62%. After 7 months at 4°C, the viability
was 28% of the initial value (= 2.3 × 1010 c.f.u. g−1 dry matter). A protection level of 89% was achieved with the biomass preparation at 1 × 108 c.f.u. ml−1 after 28 and 7 days for apples stored respectively at 5 and 25°C against Penicillium expansum. Our process is suitable to produce large quantities of the strain Ach 1-1 as biological control agent for apple preservation. 相似文献
4.
Song Quan Wu Mei Lan Lian Ri Gao So Young Park Xuan Chun Piao 《In vitro cellular & developmental biology. Plant》2011,47(6):719-724
Astragalus membranaceus is one of the most widely used traditional medicinal herbs in China, but the time required to generate a useful product in
the field production is long. The growth of adventitious root cultures was compared between cultures grown in solid, liquid,
or a 5-L balloon-type bubble bioreactor. The maximum growth ratio (final dry weight/initial dry weight) was determined for
adventitious roots grown in the bioreactor. Studies carried out to optimize biomass production of adventitious roots compared
adventitious root growth from various inoculum root lengths, inoculum densities, and aeration volume in the bioreactors. The
maximum growth ratio occurred in treatments with a 1.5-cm inoculum root length, with 30 g (fresh weight) of inoculum per bioreactor
or with an aeration volume of 0.1 vvm (air volume/culture medium volume per min). The polysaccharide, saponin, and flavonoid
content of roots from bioreactor-grown cultures were compared to roots from field-grown plants grown for 1 and 3 yr. Total
polysaccharide content of adventitious roots in the bioreactor (30.0 mg g−1 dry weight (DW)) was higher than the roots of 1-yr-old (13.8 mg g−1 DW) and 3-yr-old (21.1 mg g−1 DW) plants in the field. Total saponin (3.4 mg g−1 DW) and flavonoid (6.4 mg g−1 DW) contents were nearly identical to 3-yr-old roots and higher than that of 1-yr-old roots under field cultivation. 相似文献
5.
A high cell density cultivation method was developed to produce recombinant PvRII, a malaria vaccine candidate, in E. coli for use in vaccine studies. Cells were grown in completely defined media and glucose was fed to achieve a specific growth rate of 0.12 h–1 until cells reached 55 g dry wt l–1. Culture was then induced with 1 mm IPTG and cells were further grown for 4 h to reach 85 g dry wt l–1 at 0.1 h–1. Recombinant PvRII was purified from inclusion bodies under denaturing conditions using metal affinity chromatography which yielded 10 mg PvRII g–1 dry wt. After refolding, PvRII was greater than 98% pure, homogeneous and functionally active in that it specifically bound Duffy positive human red cells.Revisions requested 21 September 2004; Revisions received 29 October 2004 相似文献
6.
K. Parvathi R. Naresh Kumar R. Nagendran 《World journal of microbiology & biotechnology》2007,23(5):671-676
Summary Biosorption of manganese from its aqueous solution using yeast biomass Saccharomyces cerevisiae and fungal biomass Aspergillus niger was carried out. Manganese biosorption equilibration time for A. niger and S. cerevisiae were found to be 60 and 20 min, with uptakes of 19.34 and 18.95 mg/g, respectively. Biosorption increased with rise in pH,
biomass, and manganese concentration. The biosorption equilibrium data fitted with the Freundlich isotherm model revealed
that A. niger was a better biosorbent of manganese than S. cerevisiae. 相似文献
7.
A genetic transformation system has been developed for callus cells of Crataegus
aronia using Agrobacterium
tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with
5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different
types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red
colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli
were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this
is the first time to report an Agrobacterium-mediated transformation system in Crataegus
aronia. 相似文献
8.
Orlita A Sidwa-Gorycka M Malinski E Czerwicka M Kumirska J Golebiowski M Lojkowska E Stepnowski P 《Biotechnology letters》2008,30(3):541-545
Growth of Ruta graveolens shoots was induced when Bacillus sp. cell lysates were added to the culture medium. Elicitation of coumarin by this lysate was also very effective; the concentrations
of isopimpinelin, xanthotoxin and bergapten increased to 610, 2120 and 1460 μg g−1 dry wt, respectively. It also had a significant effect on the production of psoralen and rutamarin (680 and 380 μg g−1 dry wt) and induced the biosynthesis of chalepin, which was not detected in the control sample, up to 47 μg g−1 dry wt With lysates of the Pectobacterium
atrosepticum, their effect on growth was not so significant and had no effect on the induction of coumarin accumulation. But elicitation
with this lysate was much more effective for inducing the production of furoquinolone alkaloids; the concentrations of γ-fagarine,
skimmianine, dictamnine and kokusaginine rose to 99, 680, 172 and 480 μg g−1 dry wt, respectively. 相似文献
9.
In this study, Lactobacillus
fermentum (L. fermentum) F1 reduced cholesterol 48.87%. The strain was screened from cattle feces using an API 50 CHL system and the 16S rRNA sequence contrasting method. L. fermentum F1 showed acid and bile tolerance, and antimicrobial activity against pathogenic Escherichia coli and Staphylococcus aureus. L. fermentum F1 deconjugated 0.186 mM of free cholalic acid after it was incubated at 37°C in 0.20% sodium taurocholate (TCA) broth for
24 h. Heat-killed and resting cells of L. fermentum F1 showed small amounts of cholesterol removal (6.85 and 25.19 mg/g, respectively, of dry weight) compared with growing cells
(33.21 mg/g of dry weight). The supernatant fluid of the broth contained 50.85% of the total cholesterol, while the washing
buffer and cell extracts had 13.53 and 35.39%, respectively. These findings suggest that L. fermentum F1 may remove cholesterol by co-precipitating with deconjugated bile salt, assimilating with cells and by incorporation into
cellular membranes. Cholesterol assimilated by cells held 72.0% of the reduced cholesterol, while 21.65% of the reduced cholesterol
was coprecipitated with deconjugated bile salt and 5.89% was adsorbed into the surface of the cells. 相似文献
10.
AlthoughArabidopsis thaliana is known as a model plant, in molecular studies, as well as heavy metal tolerance of higher plants, there have been no detailed studies of its cadmium accumulation, tolerance and cellular distribution in a wild type of this species. In hydroponic experiments the wild type of A. thaliana (L.) Heynh cv. Columbia plants grew at cadmium concentrations varying from 5 to 100 M with phytotoxicity symptoms depending on the concentration and time of application. The concentration of cadmium in roots and shoots increased from 0.28 and 0.08 mg g–1 d.wt at 5 M Cd treatment after 7 days to 0.82 and 0.85 mg g–1 d.wt at 100 M Cd treatment after 14 days, respectively. Most of the cadmium (69–88% of its total pool) was found in shoot. Cd application induced the biosynthesis of phytochelatins (PCs) in root and shoot tissues. Studies with buthionine sulfoximine [BSO, specific inhibitor of glutathione (GSH) synthesis] supported the presence of Cd–phytochelatin complexes and their role in Cd detoxification and tolerance in wild type of A. thaliana. Cellular distribution of cadmium was examined using energy-dispersive X-ray micro-analysis. Particularly interesting was the observation of cadmium localized in the root pericycle. 相似文献
11.
Zamil SS Choi MH Song JH Park H Xu J Chi KW Yoon SC 《Applied microbiology and biotechnology》2008,80(3):531-544
The cells of psychrotrophic Pseudomonas fluorescens BM07 were found to secrete large amounts of exobiopolymer (EBP) composed of mainly hydrophobic (water insoluble) polypeptide(s) (as contain approximately 50 mol% hydrophobic amino acids, lacking cysteine residue) when grown on fructose containing limited M1 medium at the temperatures as low as 0-10 degrees C but trace amount at high (30 degrees C, optimum growth) temperature. Two types of nonliving BM07 cells (i.e., cells grown at 30 degrees C and 10 degrees C) as well as the freeze-dried EBP were compared for biosorption of mercury (Hg(II)) and cadmium (Cd(II)). The optimum adsorption pH was found 7 for Hg(II) but 6 for Cd(II), irrespective of the type of biomass. Equilibrium adsorption data well fitted the Langmuir adsorption model. The maximum adsorption (Q (max)) was 72.3, 97.4, and 286.2 mg Hg(II)/g dry biomass and 18.9, 27.0, and 61.5 mg Cd(II)/g dry biomass for cells grown at 30 degrees C and 10 degrees C and EBP, respectively, indicating major contribution of heavy metal adsorption by cold-induced EBP. Mercury(II) binding induced a significant shift of infrared (IR) amide I and II absorption of EBP whereas cadmium(II) binding showed only a very little shift. These IR shifts demonstrate that mercury(II) and cadmium(II) might have different binding sites in EBP, which was supported by X-ray diffraction and differential scanning calorimetric analysis and sorption results of chemically modified biomasses. This study implies that the psychrotrophs like BM07 strain may play an important role in the bioremediation of heavy metals in the temperate regions especially in the inactive cold season. 相似文献
12.
Su-Juan Zhao Zhong-Chun Zhang Xiang Gao Gulsum Tohsun Bao-Sheng Qiu 《Plant Cell, Tissue and Organ Culture》2009,99(1):9-16
An efficient micropropagation system for mining ecotype Sedum alfredii Hance, a newly identified Zn/Cd hyperaccumulator, was developed. Frequency of callus induction reached up to 70% from leaves
incubated on Murashige and Skoog (MS) medium supplemented with 1.0 mg l−1 2,4-dichlorophenoxy acetic acid (2,4-D) and 0.5 mg l−1 6-benzyladenine (BA), and 83% from internodal stem segments grown on MS medium with 0.1 mg l−1 2,4-D and 0.1 mg l−1 BA. Callus proliferated rapidly on MS medium containing 0.2 mg l−1 2,4-D and 0.05 mg l−1 thidiazuron. The highest number of adventitious buds per callus (17.3) and frequency of shoot regeneration (93%) were obtained
when calli were grown on MS medium supplemented with 2.0 mg l−1 BA and 0.3 mg l−1 α-naphthalene acetic acid (NAA). Elongation of shoots was achieved when these were incubated on MS medium containing 3.0 mg l−1 gibberellic acid. Induction of roots was highest (21.4 roots per shoot) when shoots were transferred to MS medium containing
2.0 mg l−1 indole 3-butyric acid rather than either indole 3-acetic acid or NAA. When these in vitro plants were acclimatized and transferred
to the greenhouse, and grown in hydroponic solutions containing 200 μM cadmium (Cd), they exhibited high efficiency of Cd
transport, from roots to shoots, and hyperaccumulation of Cd. 相似文献
13.
Hairy root cultures of Gynostemma pentaphyllum were established by infecting leaf discs with Agrobacterium rhizogenes. The dry biomass of hairy roots grown in MS medium for 49 days was 7.3 g l−1 with a gypenoside content of 38 mg g−1 dry wt. 相似文献
14.
Renata Grąbkowska Aleksandra Królicka Wojciech Mielicki Marzena Wielanek Halina Wysokińska 《Acta Physiologiae Plantarum》2010,32(4):665-673
A genetic transformation method using Agrobacterium rhizogenes was developed for Harpagophytum procumbens. The influence of three factors on hairy root formation was tested: bacterial strains (A4 and ATCC 15834), various types
of explants and acetosyringone (AS) (200 μM). The highest frequency of transformation (over 50% of explants forming roots
at the infected sites after 6 weeks of culture on Lloyd and McCown (WP) medium) was achieved using a combination of nodal
stem explants and A. rhizogenes strain A4. The addition of 200 μM AS to root induction medium was found to enhance hairy root induction but its effect varied
depending on bacterial strain and explant type. Three of the most vigorously growing hairy root clones of H. procumbens were chosen and analyzed for accumulation of iridoid and phenylethanoid glycosides. The transgenic nature of these root clones
was confirmed by PCR amplification; they were positive for rolB and rolC genes. Harpagoside, verbascoside and isoverbascoside were identified by HPLC and LC–ESI-MS as the major compounds from all
analyzed hairy root clones. The Hp-3 root clone showed the higher harpagoside content (0.32 mg g−1 dry wt.) compared with other analyzed transformed and non-tuberized untransformed roots of H. procumbens. However, the level of the compound in the hairy root clone was lower than that detected in a sample of commercially available
root tubers of H. procumbens. The Hp-3 root clone also produced high amounts of verbascoside and isoverbascoside (8.12 mg g−1 dry wt. and 9.97 mg g−1 dry wt., respectively) comparable to those found in root tubers. 相似文献
15.
The biotransformation of racemic 1-phenylethanol (30 mg) with plant cultured cells of basil (Ocimum basilicum cv. Purpurascens, 5 g wet wt) by shaking 120 rpm at 25°C for 7 days in the dark gave (R)-(+)-1-phenylethanol and acetophenone in 34 and 24% yields, respectively. The biotransformation can be applied to other 1-arylethanols
and basil cells oxidized the (S)-alcohols to the corresponding ketones remaining the (R)-alcohols in excellent ee. 相似文献
16.
Cucumber (Cucumis sativus L.) cells from suspension culture were selected for their ability to grow and divide rapidly in toxic concentration of cadmium. As a result of selection a cell suspension tolerant to 100 M cadmium chloride (CdCl2) was initiated. The selected tolerant line exhibited stable and repeatable increase in fresh and dry weight of cells in the presence of cadmium. The accumulated level of phytochelatins in cadmium sensitive (unselected) and tolerant cell line was measured by high performance liquid chromatography (HPLC) after 3, 24 h and 5 days of cadmium treatment. It was shown that in both cell lines Cd induced accumulation of phytochelatins and simultaneous glutathione depletion occurred. No distinct changes were found after 3 and 24 h of cadmium treatment whereas after 5 days of exposure to the metal, the level of phytochelatins was two times higher in the sensitive cell line as compared to the tolerant one. The accumulation of phytochelatins was correlated with cadmium concentration that increased in both cell lines during the course of cell exposure to metal. However, the level of cadmium was always lower in the tolerant cell line. The results showed no direct correlation between the tolerance of cucumber cells to Cd and the accumulated level of phytochelatins. Other mechanisms responsible for the increased tolerance of cucumber cells exposed to Cd are discussed. 相似文献
17.
At the onset of swimbladder inflation, Tinca tinca larvae were exposed for 24 h to cadmium or copper at 0.0 (control concentration), 0.1, 0.2 and 0.3 mg dm−3 at 22°C. From then larvae were reared at 25°C for 9 days in un-supplemented water. Both metals resulted in a significantly
reduced growth, survival, and retarded swimbladder inflation in a dose-response manner. The highest Cd and Cu concentration
delayed the onset of exogenous feeding (live artemia nauplii) for 2 or 1 days, respectively, comparing to the control concentration.
Our results demonstrate a highly toxic effect of Cd and Cu in the studied period of larval ontogeny, when fish seem especially
sensitive. Although, at low concentrations and long exposure period, Cu is considered more toxic to fish than Cd, our study
revealed the reverse effect for first-feeding larvae of both metals at high concentrations and short exposure. 相似文献
18.
Xiong H Turunen O Pastinen O Leisola M von Weymarn N 《Applied microbiology and biotechnology》2004,64(3):353-358
Trichoderma reesei Rut C-30 was grown on eight different natural or rare aldopentoses as the main carbon source and on mixtures of an aldopentose with d-glucose or lactose. The fungal cells consumed all aldopentoses tested, except l-xylose and l-ribose. The highest total xylanase and cellulase activities were achieved when cells were grown on l-arabinose as the main carbon source. The total xylanase activity produced by cells grown on l-arabinose was even higher than that produced by cells grown on an equal amount of lactose. In co-metabolism of d-glucose (15 g l–1) and l-arabinose (5 g l–1), the total volumetric and specific xylanase productivities were improved (derepressed) approximately 23- and 18-fold, respectively, compared to a cultivation on only d-glucose (20 g l–1). In a similar experiment, in which cells were grown on a mixture of lactose and l-arabinose, the xylanase productivity was approximately doubled, compared to a cultivation on only lactose. The cellulase productivities, however, were not improved by the addition of l-arabinose. Compared with a typical industrial fungal enzyme production process with lactose as the main carbon source, better volumetric and specific xylanase productivities were achieved both on a lactose/arabinose mixture and on a glucose/arabinose mixture. 相似文献
19.
We report a procedure for obtaining fairly pure phycocyanin from a local isolate of the cyanobacterium Synechococcus sp (Anacystis nidulans BD1). Cells were incubated with 1 mg∙mL−1 of lysozyme at 37°C for 16 h with shaking. The cell-free extract was treated with activated charcoal and chitosan. The purity
(A
620/280) of phycocyanin obtained after lysozyme treatment was up to 2.18, which could be improved to 4.72 after incubation with activated
charcoal and chitosan. The yield of phycocyanin was 80–100 mg∙g−1 dry weight of cells. The method reported here is a single-step and efficient procedure and has the potential to be adopted
for large-scale production of phycocyanin. 相似文献
20.
Hong-Sheng Wu Waseem Raza Dong-Yang Liu Cheng-Long Wu Ze-Shen Mao Yang-Chun Xu Qi-Rong Shen 《World journal of microbiology & biotechnology》2008,24(8):1297-1304
Watermelon production is threatened by fusarium wilt caused by Fusarium oxysporum f.sp. niveum (FON) in continuous cultivation system. Some elements, mainly allelochemicals, released from living roots or decayed plants
might be associated with the disease. The purpose of this work was to evaluate the possible impact of coumarin, one kind of
watermelon allelochemical, on FON. Furthermore, possible new mechanisms might be investigated during the ecological interactions
of plant-microbe. Results showed that coumarin strongly inhibited growth of FON leading to a decrease in its biomass, dry
weight of mycelia of FON in a liquid culture. The dry weight was decreased by 62.9% compared with control. The hyphal growth
of FON on plates was stopped at high (>400 mg l−1) concentrations of coumarin. At 320 mg l−1, sporulation and enzyme activities of FON were also severely suppressed by coumarin. The yield of conidia, and the activities
of proteinase, cellulase, and amylase were reduced by 98.9%, 79.7%, 29.8% and 15.9% respectively. However, conidial germination
and mycotoxin (MT) production of FON were greatly stimulated, being increased by 55.7% and 14.9 fold at 320 mg l−1 respectively. We conclude that coumarin acted as an allelochemical substance to inhibit growth and pathogenic enzyme activities
of FON but to stimulate mycotoxin production and conidial germination. It was suggested that coumarin acted as a signal transduction
element bridging plant and pathogen in the process of plant-microbe interactions. 相似文献