The flocculating yeast strain SPSC01 is a fusant strain of Saccharomyces cerevisiae and Schizosaccharomyces pombe. The use of SPSC01 to absorb Cr(VI) from Cr(VI) containing aqueous solution would greatly reduce the cost of post-adsorption separation, since the superior flocculating property of SPSC01 would allow easy separation of the Cr(VI)-biomass from the solution. In order to investigate the effects of flocculating proteins on Cr(VI) reduction and absorption by SPSC01, the absorption behaviors of SPSC01 and its parental strains were compared. The results showed that Cr(VI) removal rate of SPSC01 was almost the same as that of S. pombe, which also has flocculating ability, but was faster than that of S. cerevisiae, which has no flocculating ability. When the system reached equilibrium, the amount of total Cr adsorbed by S. pombe, SPSC01 and S. cerevisiae were 68.8%, 48.6% and 37.5%, respectively. This showed that flocculation was beneficial to Cr(VI) reduction and adsorption, and suggested that focculating proteins may play a role in enhancing the Cr(VI) adsorption capacity of SPSC01 and S. pombe. We investigated the mechanism of Cr(VI) adsorption by SPSC01 using chemical modification and FTIR. The results indicated that the major functional groups (amino, carboxyl and amide) of surface proteins may contribute to the absorption of Cr(VI).
Adsorption ; Biodegradation, Environmental ; Chromium ; isolation & purification ; Flocculation ; Saccharomyces cerevisiae ; metabolism ; Schizosaccharomyces ; metabolism ; Surface Properties ; Water Pollutants, Chemical ; isolation & purification

OBJECTIVECr(VI) removal from industrial effluents and sediments has attracted the attention of environmental researchers. In the present study, we aimed to isolate bacteria for Cr(VI) bioremediation from sediment samples and to optimize parameters of biodegradation.

METHODSStrains with the ability to tolerate Cr(VI) were obtained by serial dilution and spread plate methods and characterized by morphology, 16S rDNA identification, and phylogenetic analysis. Cr(VI) was determined using the 1,5-diphenylcarbazide method, and the optimum pH and temperature for degradation were studied using a multiple-factor mixed experimental design. Statistical analysis methods were used to analyze the results.

RESULTSFifty-five strains were obtained, and one strain (Sporosarcina saromensis M52; patent application number: 201410819443.3) having the ability to tolerate 500 mg Cr(VI)/L was selected to optimize the degradation conditions. M52 was found be able to efficiently remove 50-200 mg Cr(VI)/L in 24 h, achieving the highest removal efficiency at pH 7.0-8.5 and 35 °C. Moreover, M52 could completely degrade 100 mg Cr(VI)/L at pH 8.0 and 35 °C in 24 h. The mechanism involved in the reduction of Cr(VI) was considered to be bioreduction rather than absorption.

CONCLUSIONThe strong degradation ability of S. saromensis M52 and its advantageous functional characteristics support the potential use of this organism for bioremediation of heavy metal pollution.

Biodegradation, Environmental ; China ; Chromium ; metabolism ; Geologic Sediments ; microbiology ; RNA, Ribosomal, 16S ; genetics ; Sporosarcina ; genetics ; isolation & purification ; metabolism

OBJECTIVE: To establish a feasible evaluation index and method to identify composition of remaining metal particles on ferrochrome kitchen knife. METHODS: The small samples of remaining metal particles were rubbed from the knives using filter paper. The composition of remaining metal particles was detected by scanning electron microscopy and energy dispersive X-ray spectrometer (SEM-EDX) and GSR particle analysis function, using mathematical methods to calculate the ratio (relative amount) of Fe and Cr in remaining metal particles. RESULTS: The ratio (relative amount) of Fe and Cr of remaining metal particles had significant differences among most ferrochrome kitchen knives (P < 0.05). CONCLUSION Using GSR particle analysis function to quantitatively detect the ratio (relative amount) of Fe and Cr of remaining metal particles on ferrochrome kitchen knife, which can establish the feasible evaluation method to estimate such injury tool.
China ; Chromium/isolation & purification* ; Forensic Medicine/methods* ; Iron/isolation & purification* ; Metals/chemistry* ; Microscopy, Electron, Scanning/methods* ; Spectrometry, X-Ray Emission/methods* ; Wounds, Nonpenetrating/pathology*

A self-made anaerobic bio-filter bed which was inoculated with special sludge showed high efficiency in removing hexavalent chromium. When pump flow was 47 ml/min and COD(Cr) of wastewater was about 140 mg/L, it took 4 h to decrease the Cr6+ concentrations from about 60 mg/L to under 0.5 mg/L, compared with 14 h without carbon source addition. Cr6+ concentrations ranged from 64.66 mg/L to 75.53 mg/L, the system efficiency was excellent. When Cr6+ concentration reached 95.47 mg/L, the treatment time was prolonged to 7.5 h. Compared with the contrast system, the system with trace metals showed clear superiority in that the Cr6+ removal rate increased by 21.26%. Some analyses also showed that hexavalent chromium could probably be bio-reduced to trivalent chromium, and that as a result, the chrome hydroxide sediment was formed on the surface of microorganisms.
Bacteria, Anaerobic ; metabolism ; Biodegradation, Environmental ; Bioreactors ; microbiology ; Cell Culture Techniques ; methods ; Chromium ; isolation & purification ; pharmacokinetics ; Industrial Waste ; prevention & control ; Sewage ; microbiology ; Water Purification ; methods

The effectiveness of vitamin C in treating Cr(VI)-contaminated water is being evaluated. Cr(VI) is an identified pollutant of some soils and groundwater. Vitamin C, an important biological reductant in humans and animals, can be used to transform Cr(VI) to essentially nontoxic Cr(III). The removal efficiency was 89% when the mass concentration of vitamin C was 80 mg/L in 60 min, and nearly 100% Cr(VI) was removed when the mass concentration was 100 mg/L. Our data demonstrated that the removal efficiency was affected by vitamin C concentration, the reaction temperature and the dissolved oxygen concentration. The reaction mechanism of Cr(VI) by vitamin C was presented. Our study opens the way to use vitamin C to remediate Cr(VI)-contaminated soils and groundwater.
Ascorbic Acid ; chemistry ; Biodegradation, Environmental ; Chromium ; chemistry ; isolation & purification ; Computer Simulation ; Industrial Waste ; prevention & control ; Models, Chemical ; Oxidation-Reduction ; Oxygen ; chemistry ; Solutions ; Temperature ; Water Purification ; methods

OBJECTIVETo investigate six trace elements including Cr, Zn, Mn, Se, Cu and V of 13 traditional Chinese medicines (TCM) commonly used in diet therapy of diabetes mellitus.

METHODThe samples were prepared through digesting in a microwave oven and determined with Inductively Coupled Plasma Mass Spectrometry (ICP-MS).

RESULTThe correlative coefficients of the calibration curves were above 0.999. Standard addition recovery was 88.7% - 110.0% and RSD < or = 7.0%. Under the given analytical conditions, the results obtained showed that the contents of the six trace elements varied in these TCM samples, for element Cr, ranging between 0-11.82 microg x g(-1), Mn in 4.36-564.3 microg x g(-1), Cu in 0.55-13.34 microg x g(-1), Zn in 3.19-86.23 microg x g(-1) Se in 0-0.39 microg x g(-1) and V in 0.05-12.04 microg x g(-1), respectively.

CONCLUSIONThe possible relationship between the content of the six trace elements and 13 TCM samples for dietetic therapy of diabetes mellitus was also discussed.

Chromium ; analysis ; Copper ; analysis ; Diet, Diabetic ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Manganese ; analysis ; Mass Spectrometry ; methods ; Medicine, Chinese Traditional ; Plants, Medicinal ; chemistry ; Reproducibility of Results ; Selenium ; analysis ; Spectrophotometry, Atomic ; Trace Elements ; analysis ; Vanadium ; analysis ; Zinc ; analysis