[Urinary neutrophil gelatinase-associated lipocalin (uNGAL) and early diagnosis of paraquat poisoning patients with acute kidney injury].

OBJECTIVE: To explore the use of the urinary neutrophil gelatinase associated lipocalin (uNGAL) in the early diagnosis of paraquat poisoning patients with acute kidney injury (AKI). METHODS: Eighty five patients were from the emergency department in our hospital. Five ml blood and urine were collected from each patient at 15 min, 2, 4, 6, 8, 10, 12, 18, 24, 36, 48 and 72 h, 5 and 7d after admission. The uNGAL levels of urine were detected with ELISA test and the SCr levels were measured with creatine oxidase assay. RESULTS: Sixty two cases of paraquat intoxication suffered from AKI, the incidence was 72.94% (62/85). The SCr levels of 62 cases with AKI at 18, 24, 36, 48, 72 h and 5, 7 d after admission increased significantly, as compared with the baseline value and control group (P < 0.01). At 24, 36, 48, 72 h and 5, 7 d after admission, there was significant difference of the SCr levels between AKI group and non-AKI group (P < 0.01). At 2 h after admission, the uNGAL level of urine in paraquat intoxication AKI group was (96.21 +/- 45.32) microg/L which was significantly higher than the baseline value. At 10, 12, 18, 24, 36, 48, 72 h and 5, 7 d after admission, the uNGAL levels of urine in AKI group and non-AKI group obviously enhanced, as compared with the baseline value and control group (P < 0.01 or P < 0.05). At all time points, there was significant difference of the uNGAL level between AKI group and non-AKI group (P < 0.01). CONCLUSION: The uNGAL level of urine in paraquat intoxication patients at 2 h after admission significantly enhanced, which is earlier than enhanced SCr. So the uNGAL level of urine may serve as early diagnostic biomarker for AKI induced by paraquat intoxication.

[Clinical study of dynamic change of inflammatory factors in serum of acute paraquat rats].

OBJECTIVE: To investigate the change of inflammatory factor in lung tissue of acute paraquat (PQ) poisoned rats. METHODS: hundred SD rats were randomly divided into two groups: the normal control group (NC group, n = 10) and the PQ group (n = 80). The 1 ml saline was administered once in normal control group. The PQ group was administered with 25 mg/kg 1% PQ by intraperitoneal injection to establish the model of PQ induced renal injury. At six hours, at the first, the third and the seventh day the PQ group were sacrificed, while at the first day the normal control group was sacrificed. The level of normal tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), IL-6 in serum of rats were detected. Meanwhile, pathological changes of the renal were examined under optical microscope. RESULTS: Histopathological findings of an earlier, a large number of patients edema clearly inflammatory cell infiltration. Compared with the control group, PQ exposure of serum TNF-α, IL-2, IL-6, the level at each time point were elevated. PQ treated group 6 h and 1, 3, 7 d when the IL-2 levels were (2.16 ± 0.65), (2.95 ± 1.02), (3.05 ± 1.12), (2.21 ± 0.62) µg/L, IL-6 were (62.5 ± 8.6), (85.6 ± 13.5), (90.3 ± 15.6), (65.3 ± 9.1) ng/ml, TNF-α were (1.95 ± 0.53), (2.86 ± 0.92), (3.15 ± 1.02), (2.06 ± 0.71) µg/L, compared with the control group, are significantly higher, the differences were statistically significant (P < 0.01). CONCLUSION: acute PQ poisoning serum TNF-α, IL-2, IL-6 levels were significantly increased both early and late inflammatory factors involved in PQ poisoning the pathogenesis of renal injury.

Spoilage potential of psychrotrophic bacteria isolated from raw milk and the thermo-stability of their enzymes / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The storage and transportation of raw milk at low temperatures promote the growth of psychrotrophic bacteria and the production of thermo-stable enzymes, which pose great threats to the quality and shelf-life of dairy products. Though many studies have been carried out on the spoilage potential of psychrotrophic bacteria and the thermo-stabilities of the enzymes they produce, further detailed studies are needed to devise an effective strategy to avoid dairy spoilage. The purpose of this study was to explore the spoilage potential of psychrotrophic bacteria from Chinese raw milk samples at both room temperature (28 °C) and refrigerated temperature (7 °C). Species of Yersinia, Pseudomonas, Serratia, and Chryseobacterium showed high proteolytic activity. The highest proteolytic activity was shown by Yersinia intermedia followed by Pseudomonas fluorescens (d). Lipolytic activity was high in isolates of Acinetobacter, and the highest in Acinetobacter guillouiae. Certain isolates showed positive β-galactosidase and phospholipase activity. Strains belonging to the same species sometimes showed markedly different phenotypic characteristics. Proteases and lipases produced by psychrotrophic bacteria retained activity after heat treatment at 70, 80, or 90 °C, and proteases appeared to be more heat-stable than lipases. For these reasons, thermo-stable spoilage enzymes produced by a high number of psychrotrophic bacterial isolates from raw milk are of major concern to the dairy industry. The results of this study provide valuable data about the spoilage potential of bacterial strains in raw milk and the thermal resistance of the enzymes they produce.

Construction and confirmation of a recombinant adenovirus vector of survivin / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To construct a recombinant adenovirus of survivin vector and provid valuable reference for gene therapy of laryngeal cancer.</p><p><b>METHODS</b>The survivin gene was cloned by PCR. After confirmation by enzyme restriction analysis and sequencing, the gene and the adenovirus vector were recombined together to construct the recombinant adenovirus vector. The recombinant adenovirus vector was confirmed via both sequencing and digestion restriction analysis, and then linearized and transfected into the HEK 293 cell line to generate recombinant adenovirus.</p><p><b>RESULTS</b>The sequence analysis demonstrated that the survivin gene sequence was the same as published in the literature, suggesting that a recombinant adenovirus vector has been successfully constructed.</p><p><b>CONCLUSIONS</b>A survivin recombinant adenovirus has been successfully constructed.</p>

Optimization of acidic extraction of astaxanthin from Phaffia rhodozyma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Optimization of a process for extracting astaxanthin from Phaffia rhodozyma by acidic method was investigated, regarding several extraction factors such as acids, organic solvents, temperature and time. Fractional factorial design, central composite design and response surface methodology were used to derive a statistically optimal model, which corresponded to the following optimal condition: concentration of lactic acid at 5.55 mol/L, ratio of ethanol to yeast dry weight at 20.25 ml/g, temperature for cell-disruption at 30 degrees C, and extraction time for 3 min. Under this condition, astaxanthin and the total carotenoids could be extracted in amounts of 1294.7 microg/g and 1516.0 microg/g, respectively. This acidic method has advantages such as high extraction efficiency, low chemical toxicity and no special requirement of instruments. Therefore, it might be a more feasible and practical method for industrial practice.

Construction of recombinant industrial Saccharomyces cerevisiae strain with bglS gene insertion into PEP4 locus by homologous recombination / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The bglS gene encoding endo-l,3-1,4-beta-glucanase from Bacillus subtilis was cloned and sequenced in this study. The bglS expression cassette, including PGK1 promoter, bglS gene fused to the signal sequence of the yeast mating pheromone alpha-factor (MFalpha1(S)), and ADH1 terminator with G418-resistance as the selected marker, was constructed. Then one of the PEP4 allele of Saccharomyces cerevisiae WZ65 strain was replaced by bglS expression cassette using chromosomal integration of polymerase chain reaction (PCR)-mediated homologous recombination, and the bglS gene was expressed simultaneously. The recombinant strain S. cerevisiae (SC-betaG) was preliminarily screened by the clearing hydrolysis zone formed after the barley beta-glucan was hydrolyzed in the plate and no proteinase A (PrA) activity was measured in fermenting liquor. The results of PCR analysis of genome DNA showed that one of the PEP4 allele had been replaced and bglS gene had been inserted into the locus of PEP4 gene in recombinant strains. Different endo-l,3-1,4-beta-glucanase assay methods showed that the recombinant strain SC-betaG had high endo-l,3-1,4-beta-glucanase expression level with the maximum of 69.3 U/(h.ml) after 60 h of incubation. Meanwhile, the Congo Red method was suitable for the determination of endo-l,3-1,4-beta-glucanase activity during the actual brewing process. The current research implies that the constructed yeast strain could be utilized to improve the industrial brewing property of beer.

Enhanced production of elastase by Bacillus licheniformis ZJUEL31410: optimization of cultivation conditions using response surface methodology / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Sequential methodology based on the application of three types of experimental designs was used to optimize the fermentation conditions for elastase production from mutant strain ZJUEL31410 of Bacillus licheniformis in shaking flask cultures. The optimal cultivation conditions stimulating the maximal elastase production consist of 220 r/min shaking speed, 25 h fermentation time, 5% (v/v) inoculums volume, 25 ml medium volume in 250 ml Erlenmeyer flask and 18 h seed age. Under the optimized conditions, the predicted maximal elastase activity was 495 U/ml. The application of response surface methodology resulted in a significant enhancement in elastase production. The effects of other factors such as elastin and the growth factor (corn steep flour) on elastase production and cell growth were also investigated in the current study. The elastin had no significant effect on enzyme-improved production. It is still not clear whether the elastin plays a role as a nitrogen source or not. Corn steep flour was verified to be the best and required factor for elastase production and cell growth by Bacillus licheniformis ZJUEL31410.

Effect of cultivating conditions on alpha-galactosidase production by a novel Aspergillus foetidus ZU-G1 strain in solid-state fermentation / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The work is intended to achieve optimum culture conditions of alpha-galactosidase production by a mutant strain Aspergillus foetidus ZU-G1 in solid-state fermentation (SSF). Certain fermentation parameters involving moisture content, incubation temperature, cultivation period of seed, inoculum volume, initial pH value, layers of pledget, load size of medium and period of cultivation were investigated separately. The optimal cultivating conditions of alpha-galactosidase production in SSF were 60% initial moisture of medium, 28 degrees C incubation temperature, 18 h cultivation period of seed, 10% inoculum volume, 5.0 approximately 6.0 initial pH of medium, 6 layers of pledget and 10 g dry matter loadage. Under the optimized cultivation conditions, the maximum alpha-galactosidase production was 2 037.51 U/g dry matter near the 144th hour of fermentation.

Studies on optimization of nitrogen sources for astaxanthin production by Phaffia rhodozyma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

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 (NH(4))(2)SO(4), KNO(3) 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 (NH(4))(2)SO(4), 0.49 g/L KNO(3) 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.

Optimization of elastolysis conditions and elastolytic kinetic analysis with elastase from Bacillus licheniformis ZJUEL31410 / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The solubilization of elastin by Bacillus licheniformis elastase cannot be analyzed by conventional kinetic methods because the biologically relevant substrate is insoluble and the concentration of enzyme-substrate complex has no physical meaning. In this paper we report the optimization of elastolysis conditions and analysis of elastolytic kinetics. Our results indicated that the hydrolyzing temperature and time are very important factors affecting elastolysis rate. The optimized conditions using central composite design were as follows: elastolysis temperature 50 degrees C, elastase concentration 1 x 10(4) U/ml, elastin 80 mg, elastolytic time 4 h. Investigation of the effects of substrate content, elastase concentration and pH was also revealed that low or high elastin content inhibits the elastolysis process. Increasing elastase improves elastin degradation, but high elastase may change the kinetics characterization. Alkaline environment can decrease elastin degradation rate and pH may affect elastolysis by changing elastase reaction pH. To further elucidate the elastolysis process, the logistic model was used to elastolysis kinetics study showing clearly that the logistic model can reasonably explain the elastolysis process, especially under lower elastase concentration. However, there is still need for more investigations with the aid of other methods, such as biochemical and molecular methods.

The influences of lactose as an inducer on expression of plant des-pGlu1-brazzein in Escherichia coli / 生物工程学报

Expression strain of des-pGlu1-brazzein was constructed and the conditions using lactose as inducer was also optimized. The Influences of three factors which were lactose concentration, induction time and inducing temperature on the growth of strain and on the yield of des-pGlul-Brazzein was analyzed in detail. The result indicated that high lactose concentration inhibit the growth of strains (P < 0.01) but made no difference on expression of target protein between 0.5%-5% (P > 0.05), Biomass would be improved as time passed (P < 0.01), but the yield of target protein didn't increase obviously at 30 degrees C compared with at 37 degrees C. Further result showed that the greater expressed level of des-pGlul-Brazzein, as high as about 20% of total cell protein, could be achieved after the strain had been induced with 0.5% lactose under 28 degrees C - 30 degrees C for 4 h.

Extraction optimization study of flavonoids from Humulus lupulus / 中国中药杂志

<p><b>OBJECTIVE</b>To optimize extracting parameters of flavonoids from Humulus lupulus.</p><p><b>METHOD</b>Based on the single factors test on ethanol concentration, material and solvent ratio, extracting temperature and extracting time, orthogonal test was performed and the best combination was confirmed.</p><p><b>RESULT</b>With the optimized technology, the maximal extracting amount of flavonoids from H. lupulus was 78 mg x g(-1).</p><p><b>CONCLUSION</b>The optimal techniques obtained are 45% ethanol extracting at 60 degrees C with material and solvent ratio 1:25 for 90 min.</p>

Synthesis and paste properties of octenyl succinic anhydride modified early Indica rice starch / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Octenyl succinic anhydride (OSA) modified early Indica rice starch was prepared in aqueous slurry systems using response surface methodology. The paste properties of the OSA starch were also investigated. Results indicated that the suitable parameters for the preparation of OSA starch from early Indica rice starch were as follows: reaction period 4 h, reaction temperature 33.4 degrees C, pH of reaction system 8.4, concentration of starch slurry 36.8% (in proportion to water, w/w), amount of OSA 3% (in proportion to starch, w/w). The degree of substitution was 0.0188 and the reaction efficiency was 81.0%. The results of paste properties showed that with increased OSA modification, the starch derivatives had higher paste clarity, decreased retrogradation and better freeze-thaw stability.

Effective extraction of elastase from Bacillus sp. fermentation broth using aqueous two-phase system / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

This paper presents the evaluation of an aqueous two-phase system (ATPS) for extracting elastase produced by Bacillus sp. EL31410. The elastase and cell partition behavior in polyethylene glycol (PEG)/salt systems was investigated. The suitable system for elastase extraction was PEG/KH(2)PO(4)-K(2)HPO(4), in which elastase is mainly partitioned into the PEG-rich phase, while the cells remained in the other phase. The influence of defined system parameters (e.g. PEG molecular mass, pH, NaCl addition) on the partitioning behavior of elastase is described. The concentration of phase forming components, PEG and KH(2)PO(4)-K(2)HPO(4), was optimized for elastase recovery by means of response surface methodology, and it was found that they greatly influenced extraction recovery. The optimal ATPS was 23.1% (w/w) PEG 2 000 and 11.7% (w/w) KH(2)PO(4)-K(2)HPO(4). The predicted recovery was about 89.5%, so this process is suggested to be a rapid and convenient method for elastase extraction.

Batch and fed-batch production of butyric acid by clostridium butyricum ZJUCB / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, this study then compared batch and fed-batch fermentation of butyric acid production at pH 6.5. Maximum value (16.74 g/L) of butyric acid concentration was obtained in fed-batch fermentation compared to 12.25 g/L in batch fermentation. It was concluded that cultivation under fed-batch fermentation mode could enhance butyric acid production significantly (P<0.01) by C. butyricum ZJUCB.

Application of derivative ratio spectrophotometry for determination of beta-carotene and astaxanthin from Phaffia rhodozyma extract / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

A derivative ratio spectrophotometric method was used for the simultaneous determination of beta-carotene and astaxanthin produced from Phaffia rhodozyma. Absorbencies of a series of the standard carotenoids in the range of 441 nm to 490 nm demonstrated that their absorptive spectra accorded with Beer's law and that the additivity when the concentrations of beta-carotene and astaxanthin and their mixture were within the range of 0 to 5 microg/ml, 0 to 6 microg/ml, and 0 to 6 microg/ml, respectively. When the wavelength interval (lambda) at 2 nm was selected to calculate the first derivative ratio spectra values, the first derivative amplitudes at 461 nm and 466 nm were suitable for quantitatively determining beta-carotene and astaxanthin, respectively. Effect of divisor on derivative ratio spectra could be neglected; any concentration used as divisor in range of 1.0 to 4.0 microg/ml is ideal for calculating the derivative ratio spectra values of the two carotenoids. Calibration graphs were established for beta-carotene within 0-6.0 microg/ml and for astaxanthin within 0-5.0 microg/ml with their corresponding regressive equations in: y=-0.0082x-0.0002 and y=0.0146x-0.0006, respectively. R-square values in excess of 0.999 indicated the good linearity of the calibration graphs. Sample recovery rates were found satisfactory (>99%) with relative standard deviations (RSD) of less than 5%. This method was successfully applied to simultaneous determination of beta-carotene and astaxanthin in the laboratory-prepared mixtures and the extract from the Phaffia rhodozyma culture.

Optimization of angiotensin I-converting enzyme (ACE) inhibition by rice dregs hydrolysates using response surface methodology / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Angiotensin I-converting enzyme (ACE) inhibitory peptides have been shown to have antihypertensive effects and have been utilized for physiologically functional foods and pharmaceuticals. The ACE inhibitory ability of a hydrolysate is determined by its peptide composition. However, the peptide composition of a hydrolysate depends on proteolytic enzyme and the hydrolysis conditions. In this study, the effect of process conditions on the ACE inhibitory activity of rice dregs hydrolyzed with a trypsin was investigated systematically using response surface methodology. It was shown that the ACE inhibitory activity of rice dregs hydrolysates could be controlled by regulation of five process conditions. Hydrolysis conditions for optimal ACE inhibition were defined using the response surface model of fractional factorial design (FFD), steepest ascent design, and central composite design (CCD).

Partitioning and purification of extracellular beta-1,3-1,4-glucanase in aqueous two-phase systems / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The partition behaviors of beta-1,3-1,4-glucanase, alpha-amylase and neutral proteases from clarified and whole fermentation broths of Bacillus subtilis ZJF-1A5 were investigated. An aqueous two-phase system (polyethylene glycol (PEG)/MgSO(4)) was examined with regard to the effects of PEG molecular weight (MW) and concentration, MgSO(4) concentration, pH and NaCl concentration on enzyme partition and extraction. The MW and concentration of PEG were found to have significant effects on enzyme partition and extraction with low MW PEG showing the greatest benefit in the partition and extraction of beta-glucanase with the PEG/MgSO(4) system. MgSO(4) concentration influenced the partition and extraction of beta-glucanase significantly. pH had little effect on beta-glucanase or proteases partition but affected alpha-amylase partition when pH was over 7.0. The addition of NaCl had little effect on the partition behavior of beta-glucanase but had very significant effects on the partitioning of alpha-amylase and on the neutral proteases. The partition behaviors of beta-glucanase, alpha-amylase and proteases in whole broth were also investigated and results were similar to those obtained with clarified fermentation broth. A two-step process for purifying beta-glucanase was developed, which achieved beta-glucanase recovery of 65.3% and specific activity of 14027 U/mg, 6.6 times improvement over the whole broth.

Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.) / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO(2) extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50 degrees C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops.

Isolation of 2,4-dichlorophenol degrading bacterium strain and cloning and expression of its 2,4-dichlorophenol hydroxylase gene / 生物工程学报

2,4-Dichlorophenol is toxic and biorefratory organic pollutant. A 2,4-dichlorophenol degrading bacterial strain GT241-1, identified as Pseudomonas sp., was isolated from soil samples which was collected from drainage area of several 2,4-dichlorophenol producing factories. Strain GT241-1 had strong 2,4-dichlorophenol degrading ability, it could decompose 91% 2, 4-dichlorophenol of 90 mg/L within 48 hours at 25 - 30 degrees C, and could utilize 2,4-dichlorophenol, 2,4-dichlorophenoxyacetic acid (2,4-D), benzoate and catechol as sole carbon and energy source. Southern blot showed that 2,4-dichlorophenol hydroxylase gene (dcpA) of strain GT241-1 locates on the about 10kb EcoR I/Xba I fragment. This fragment was recovered, linked to the vecter pUC19 and transformed into the E. coli DH5alpha. A aim transformant, Z539, was obtained by dot blotting from about 1200 transformants. PCR and the sequencing results shew that the whole dcpA gene is contained within the 10kb EcoR I /Xba I fragment of pZ539. This fragment was shortened to about 2.4kb by HindmIII. The shorted fragment was subcloned to vecter pRSET-B to get a transformant BS1-12. The subcloned fragment was sequenced. Sequencing results showed that the whole length of the subcloned fragment containing dcpA is 2389bp and the nucleotide span of coding region is from number 276 to number 2072 (1797 bp), with ATG and TAA as start and stop codon respectively. The sequence analysis of dcpA and the deduced amino acid encoded by dcpA showed that they are different from the relative sequences registered in the GenBank. The subcloned fragment carry the promoter of dcpA, this can deduce from the fact that the upflow length of dcpA coding region is 275bp, and further confirmed by the 2,4-dichlorophenol hydroxylase activity measurement results. The 2,4-dichlorophenol hydroxylase activity of transformant Z539 and BS1-12 were detected, the results showed these transformants have 2,4-dichlorophenol hydroxylase activity. By comparison, the activity of these transformants were lower than that of the strain GT241-1.