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The red sword bean (Canavalia gladiata) is an underutilized edible bean cultivated in China. It was previously found to have the highest content of antioxidant polyphenols among 42 edible beans, mainly gallic acid, and gallotannins in its red bean coat, an apparently unique characteristic among edible beans. In this study, the main phenolic compounds in red sword bean coats were further separated by Sephadex LH-20 column chromatography, and identified by LC-MS/MS. Furthermore, the FRAP and ABTS antioxidant activities and antibacterial activity (diameter of inhibition zone, DIZ) of main gallotannin-rich fractions were tested. Our results showed that gallotannins of red sword bean coats were mainly comprised of monogalloyl to hexagalloyl hexosides. Interestingly, tetragalloyl, pentagalloyl, and hexagalloyl hexosides were identified as the possible candidates responsible for the red color of the coats. On the other hand, gallotannin-rich fractions exhibited diverse antioxidant and antibacterial activities, and tetragalloyl hexoside overall had the highest free radical scavenging and antibacterial activities. The degree of galloylation did not completely explain the structure-function relationship of gallotannins isolated from red sword bean coats, as there should exist other factors affecting their bioactivities. In conclusion, red sword bean coats are excellent natural sources of gallotannins, and their gallotannin-rich extracts can be utilized as natural antioxidant and antibacterial agents with potential health benefits as well as application in food industry.

The red sword bean (Canavalia gladiata) is an underutilized edible bean cultivated in China. It was previously found to have the highest content of antioxidant polyphenols among 42 edible beans, mainly gallic acid, and gallotannins in its red bean coat, an apparently unique characteristic among edible beans. In this study, the main phenolic compounds in red sword bean coats were further separated by Sephadex LH-20 column chromatography, and identified by LC-MS/MS. Furthermore, the FRAP and ABTS antioxidant activities and antibacterial activity (diameter of inhibition zone, DIZ) of main gallotannin-rich fractions were tested. Our results showed that gallotannins of red sword bean coats were mainly comprised of monogalloyl to hexagalloyl hexosides. Interestingly, tetragalloyl, pentagalloyl, and hexagalloyl hexosides were identified as the possible candidates responsible for the red color of the coats. On the other hand, gallotannin-rich fractions exhibited diverse antioxidant and antibacterial activities, and tetragalloyl hexoside overall had the highest free radical scavenging and antibacterial activities. The degree of galloylation did not completely explain the structure-function relationship of gallotannins isolated from red sword bean coats, as there should exist other factors affecting their bioactivities. In conclusion, red sword bean coats are excellent natural sources of gallotannins, and their gallotannin-rich extracts can be utilized as natural antioxidant and antibacterial agents with potential health benefits as well as application in food industry.

This article has been removed: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).Further to an investigation the 2011 International Conference on Energy Systems and Electric Power (ESEP 2011), Energy Procedia, Volume 13 has been removed by the publisher due to insufficient assurances by the programme organisers that the professional ethical codes of publishing and standards were applied consistently. For author enquiries please contact: oxfordcopyrights@elsevier.com.

Canna edulis Ker by-product was recycled and utilized after starch extraction. The chemical composition, physical properties and antioxidant activity of the by-product were investigated. The by-product was mainly composed of dietary fiber (54.84% measured by AOAC method), and the insoluble dietary fiber constituted the major fraction. Then, the chemical composition of dietary fiber was tested using modified AOAC and Englyst methods. The results showed that dietary fiber was comprised of cellulose, hemicelluloses (including xyloglucans, arabinoxylans and glucuronoxylans), pectin and lignin. Moreover, the by-product contained relatively high content of phenolic compounds and exhibited a moderate antioxidant activity. In addition, the by-product showed both high water-holding capacity (12.5 mL/g) and oil-holding capacity (14 mL/g), and its suspension exhibited controllable viscosity. Therefore, the by-product from C. edulis is not only a source of dietary fiber but also a functional ingredient for food industry.

BACKGROUND: Microwave heat/moisture treatment (MWT) is being used increasingly in food processing, but very little research has been carried out on its effect on tuber starches. In this study, Canna edulis Ker tuber starch was subjected to MWT with moisture contents ranging from 20 to 45% (w/w), and the effects of MWT on the physicochemical properties of the starch, including the extent of amylose leaching, enzymatic digestibility, X-ray diffraction (XRD) and differential scanning calorimetry (DSC) characteristics, were determined. RESULTS: In the process of MWT, temperature exhibited a positive correlation with microwave power and moisture content. When amylose leaching was used as an index, a moisture content of 40%, a treatment time of 15 min and a microwave power of 800 W were found to be the optimal conditions for MWT of C. edulis starch. The enzymatic digestibility changed under different treatment conditions. Furthermore, XRD measurements revealed a change in crystalline structure from type B to type A and an increased degree of crystallinity. Thermal (DSC) studies showed higher values of To, Tp and Tc of endothermic peaks, and exothermic peaks were also observed. CONCLUSION: MWT increased the degree of crystallinity, resulting in more resistant fractions in C. edulis starch, which will be beneficial to human health. Copyright © 2009 Society of Chemical Industry

Assimilation of phosphate by Chlorella pyrenoidosa was 0.81-8.1 mg PO(4)-P/g dry weight for heterotrophic cultures and 0.81-16.1 mg/g for mixotrophic cultures. Optimal carbon:phosphorous (C/P) ratios were 206:1-2060:1 and 103:1-2060:1 for heterotrophic and mixotrophic cultivations, respectively. These requirements for phosphate for growth of C. pyrenoidosa under either heterotrophic or mixotrophic conditions are much less (6.25-62.5 or 3.12-62.5-fold at 10 g glucose/l) than its concentration in basal medium.

Rheological properties of Chlorella pyrenoidosa culture grown heterotrophically in a 14 L fermentor were investigated. It was found that the fluid viscosity was rather low and remained almost unchanged during the cultivation, implying that no (or very few) viscous substances were excreted into the medium. Investigation of the condensed suspension of C. pyrenoidosa showed that for biomass concentration under 150 g.L−1, the suspension of C. pyrenoidosa exhibited Newtonian behavior, and the fluid viscosity was rather low (about 40 mPa·s) and increased very slowly with the increase in cell concentration. With further increase in biomass concentration however, the fluid rheological behavior changed to non-Newtonian, and the fluid viscosity increased rapidly with the increase in cell concentration. From the viewpoint of rheology, C. pyrenoidosa is an excellent organism for high-cell-density culture, and there will be no rheological problems at cell densities under 150 g.L−1.

Chlorella is a promising alternative resource of lutein (xanthophyll) production as it can be cultivated heterotrophically in fermentors. In this paper, a kinetic model for lutein production by heterotrophic Chlorella pyrenoidosa was developed based on batch cultivations in 250-ml flasks and a 19-l fermentor. The model was validated by experimental data from two fed-batch cultivations performed in the same fermentor. The dynamic behavior of lutein production by C. pyrenoidosa with various concentrations of glucose and nitrogen was analyzed based on the kinetic model. Model-based analyses suggested that glucose concentrations between 5 and 24 g/l and nitrogen concentrations between 0.7 and 12 g/l during the cultivation were favorable for lutein production by heterotrophic C. pyrenoidosa. It also showed that fed-batch cultivations are more suitable for efficient production of lutein than batch ones. The results obtained in this study may contribute to commercial lutein production by heterotrophic Chlorella.

Three chloroplast genes, chlL, chlN and chlB, encoding the light-independent protochlorophyllide oxidoreductase (LIPOR) in Chlorella protothecoides CS-41 growing either photoautotrophically, mixotrophically or heterotrophically, were all transcribed constitutively independent of illumination and presence of glucose. Steady-state amounts of all three transcripts in the light-grown cells were, however, approximately two- to three-fold greater than those in the dark-grown cells. In addition, Western blotting demonstrated that approximately the same amount of protein was present in cultures grown mixtrophically or heterotrophically both containing glucose. However, much less protein was in photoautotrophic cells. These results suggest that LIPOR activity depends on post-transcriptional and post-translational regulation. Moreover, the fact that LIPOR accumulates in the light-grown cells indicates that LIPOR, which was thought to work only in darkness, may partially account for the protochlorophyllide photoreduction in light. Therefore, LIPOR switches on both in light and in darkness.

Production of lutein by the green microalga Chlorella protothecoides grown heterotrophically in a fermentor using glucose as the carbon source and urea as the nitrogen source was investigated. An unstructured kinetic model was proposed to describe the microalgal culture system including cell growth, lutein formation, as well as glucose and nitrogen consumption. The inhibition potentials of biomass, product and substrates on growth and lutein formation were examined and incorporated into the kinetic model. Values of the kinetic model parameters were estimated. The resulting model predictions were in good agreement with the experimental results. The model can be helpful in scale-up, optimization and control of the C. protothecoides culture process, and can also be used as a guideline for similar microalgal cultivation systems.

The influence of initial glucose concentrations on the production of biomass and lutein by Chlorella protothecoides CS-41 was investigated in batch cultures using both shake flasks and fermentors. The maximum biomass concentration increased from 4·9 to 31·2 g litre −1 dry cells with an increase in initial glucose concentration from 10 to 80 g litre −1 . An even higher initial glucose concentration (100 g litre −1 ) resulted in a lower biomass concentration, a lower specific growth rate, a lower growth yield coefficient and a considerably longer lag phase, which might be due to substrate inhibition. The initial glucose level also had a significant effect on the production of lutein. In a 3·7-litre fermentor an increase in lutein production from 19·39 to 76·56 mg litre −1 was obtained with an increase in initial glucose concentration from 10 to 40 g litre −1 , within which range, lutein yield coefficient was constant ( Y Itn =1·90±0·02 mg g −1 ). A simple substrate inhibition model was developed, which fitted the experimental data better than the classical Haldane model. A group of time-dependent kinetic models for algal cultivation in fermentors were also constructed, which were in good agreement with the experimental results and could be employed to predict the production of biomass and lutein, and the consumption of glucose in fermentor cultures.

Seven Chlorella strains representing three species obtained from culture collections and research laboratories were screened for their potential of heterotrophic production of lutein on two different media (Basal and Kuhl) containing glucose. While both media supported good growth and lutein formation of the seven strains in darkness, higher biomass concentrations and lutein content were achieved on Basal medium. Chlorella protothecoides CS-41 was chosen from the seven strains for further investigation due to its higher productivities of both biomass and lutein. The maximal biomass concentration and lutein content of C. protothecoides cultivated heterotrophically with 9 g L-1 glucose in a 3.7-L fermentor were respectively 4.6 g dry cells L-1 and 4.60 mg lutein g-1 dry cells on Basal medium, and 4.0 g dry cells L-1 and 4.36 mg lutein g-1 dry cells on Kuhl medium. The heterotrophic cultivation process was scaled up successfully to 30 L using a fermentor, in which the Basal medium containing 36 g L-1 glucose was used; the maximal biomass concentration of 16.4 g dry cells L-1, specific growth rate of 0.92 d-1,lutein content of 4.85 mg lutein g-1 dry cells,growth yield of 0.47 g dry cells g-1 glucose and lutein yield of 1.93 mg lutein g-1 glucose were respectively achieved.

To establish and evaluate a molecular diagnostic method for routine monitoring of four types of diarrheagenic Escherichia (E.) coli (DEC)and to study the distribution of four types of DEC isolated from diarrheal patients in Shanghai.DEC-PCR standard operation procedure(SOP)had been developed for DEC detection and isolation, using the Statens Serum Institute (SSI) DEC PCR kits with multiplex PCR technique after verification tests on reference strains. Diarrhea specimens from 3 clinical hospitals in Shanghai were tested from June to September, 2012.Specificity of the PCR kit was 100% by verification on the 26 DEC reference strains. A total number of 218 DEC isolates, including 181 fermented lactose and 37 unfermented lactose were identified from the 1887 stool specimens of diarrhea patients, with positive rate as 11.6%. The most common pathogen(54.1%, 118/218)was enteropathogenic E. coli(EPEC), followed by enterotoxigenic E. coli(ETEC, 41.3%, 90/218), enteroinvasive E. coli (EIEC, 4.1%, 9/ 218) and Shigatoxin-producing E. coli(STEC, 0.5%, 1/218)in addition to 18 Shigella isolates. ETEC dominated in diarrhea patients with foreign residency, as well as 1/3 were perinatal stage of neonatal ETEC of all diarrhea cases under the age of 5, while EPEC dominated in the Chinese diarrhea patients especially among young kids under the age of 2.Data was reliable after assessment on this molecular diagnostics and seperation procedures used for the routine monitoring on four types of DEC, while the diagnosis and reference ability of DEC regarding the laboratories net-working on food-borne pathogens need to be built up and improved.

To better decide the sequence of ammunition sort choice when one object is attacked by several kinds of ammunitions, that is the ammunition target matching problem for artillery field. In this paper, first depicting ammunition damage effect and target anti-damage effect and constructing the ammunition target matching index system. Then, rough set theory was applied to reduce the index system and determine the weights of key index with comprehensively considering the matching within various effects, and grey relation theory was introduced to determine the comprehensive matching sequence of ammunition target. Finally, this method for ammunition target matching is proved to be feasible though an actual case and could help commanders or command departments to make proper decision on optimal firepower assignment.

We proposed a new approach for target value sequencing problem using weighted evidence theory. Target value evaluation index system is constructed located at artillery battlefield, the uncertain target information are fused based on the evidence theory, the index weight is decided based on analytic network process. The case proves the reliability of the results and the validity of this method. This method provides the artillery commander with a reference to the theoretic basis of decision-making of the target value sequencing.

Simulation data is necessary in equipment test and evaluation, especially in small sample condition. Static consistency check is important to ensure the data is available. In this thesis, the method of static consistency check for simulation data in small sample condition with order statistics was presented. Based on the discussion of these methods and use some decisions for reference, arbitrary distributions of small sample consistency check ideas and methods was studied using difference quotient series statistics in variable scale, which can solve the problem of consistency check easily, and has a better accuracy. At last, an example was given to demonstrate the feasibility of the method.

Five hundred fifty samples were collected from five chicken farms in Shanghai during March 2005 to October 2006. Twenty-five samples tested positive for Salmonella from a total of 550 samples, of which 500 were obtained from feces of healthy chickens and 50 were obtained from diseased chicks. The 25 presumptive Salmonella isolates were confirmed by the API 20E identification kit. Serotyping of these isolates by agglutination tests with antiserum displayed seven serovars; genotyping of these isolates with multilocus sequence typing demonstrated six sequence type (ST) patterns (i.e., ST-11, ST-19, ST-92, ST-96, ST-290, and ST-367). The multilocus sequence typing data revealed that some of these strains, isolated from different farms, might have the same ST and might come from the same source. The susceptibilities of these strains to 14 antimicrobials were determined; most of the isolates (13 of 25) were resistant to doxycycline and tetracycline, and two isolates were resistant to cefotaxime and ceftazidime, but none was resistant to gentamicin or kanamycin.

Chlorella is a promising alternative source of lutein, as it can be cultivated heterotrophically with high efficiency. In this study, the carotenoids in Chlorella pyrenoidosa heterotrophically cultivated in a 19-litre fermentor have been analyzed and determined by using HPLC and HPLC-MS. A biochemical system theory (BST) model was developed for understanding the regulatory features of carotenoid metabolism during the batch cultivation. Factors that influence lutein production by C. pyrenoidosa were discussed based on the model. It shows that low flux for lycopene formation is the major bottleneck for lutein production, while by-product syntheses and inhibitions affect the cellular lutein content much less. However, with further increase of the cellular lutein content, the inhibition on lycopene formation by lutein may become a limiting factor. Although speculative, these results may provide useful information for further elucidation of the regulatory mechanisms of carotenoid biosynthesis in Chlorella and modifying its metabolic network to enhance lutein production., Alga Chlorella mogući je izvor luteina, jer se može uspješno uzgajati u heterotrofnim uvjetima. Stoga su u radu primjenom HPLC i HPLC-MS metoda ispitani karotenoidi iz alge Chlorella pyrenoidosa, uzgojene u heterotrofnim uvjetima u bioreaktoru volumena 19 L. Razvijen je model biokemijskog teorijskog sustava za razumijevanje regulacije metabolizma karotenoida pri šaržnom uzgoju. Na temelju tog modela razmatrani su faktori koji utječu na proizvodnju luteina s pomoću C. pyrenoidosa. Utvrđeno je da „usko grlo” u proizvodnji luteina nastaje zbog slabog metaboličkog toka sinteze likopena, a da nastajanje nusprodukata i njihov inhibicijski učinak puno manje utječu na količinu luteina u stanicama. Međutim, povećanje količine luteina u stanicama može inhibirati sintezu likopena i stoga postati ograničavajući faktor u proizvodnji. Ovi rezultati, iako još nepotvrđeni, mogu dati korisne informacije za pojašnjenje mehanizma regulacije biosinteze karotenoida u algi Chlorella i modifikaciju metaboličkog procesa radi dobivanja veće količine luteina.

To apply and evaluate new methods regarding specific gene and antigen detection in plague surveillance program.1798 samples from natural foci of plague were tested, using internal quality control multiple-polymerase chain reaction, F1 antigen marked by immuno chromatographic assay and enzyme linked immunosorbent assay. Culture of Yersinia pestis and reverse indirect hemagglutination assay were used as reference diagnostic methods.The overall positive rate of culture on Yersinia pestis together with gene and antigen detection was 7.34%, showing an 16.81% increase when comparing to 6.28% using Yersinia pestis culture method alone. The rate of coincidence was 97.13%.The new standard being used for specific gene and antigen detection could increase the positive rate of diagnosis on plague.

Surface-attached populations of bacteria comprising either single or multiple species were referred to as biofilm. The bacteria in the biofilm had more resistant ability against antibiotics and disinfectors, which could cause the constituent clinical affection or food contamination. In order to isolate and characterize the genes involved in biofilm formation of Listeria monocytogenes, the plasmid pTV1-OK containing the transposon Tn917 was transformed into the protoplasm of Listeria monocytogenes. After cultivating for 4 days, twenty positive transformants per microgram DNA were generated. Some transformants were selected for inducing transposition in water bath overnight at 42 degrees C, and the transposition efficiency of Tn917 was 10(-7). The LM-49 strain with higher ability on biofilm formation than the wild strain was obtained by microtiter plate assaying, and the purple ring formed by the LM-49 was thicker than that by the wild after a 4-day incubation. The PCR result using specific primers of Tn917 proved that Tn917 was inserted into the genome of L. monocytogenes. So the LM-49 strain can be regarded as the mutant of biofilm formation, and the higher ability of biofilm formation is caused by the insertion of Tn917.

To understand the molecular biological characteristics in order to analyse the genetic background of Yersinia pestis in China.Primary datum on ribotyping, pulsed field gene electrophoresis (PFGE), random amplified polymorphic DNA (RAPD) and insertion sequence (IS) of Yersinia pestis were used and under cluster analysis. Genetic interval and various methods of recognized molecular feature between different strains were evaluated.Ribotypes the PFGE types seemed to be corresponding. Stains from Microtus fuscus and area in Tibet Zhongba belonged to 7 copy rRNA gene and the genetic interval were the far more with 6 copy rRNA gene stains, and not definite with RAPD, but with many exceptions. The genetic interval between strains were showed by resemble value.Yersinia pestis in China had its own manifold, particular molecular biological characteristics due to natural barriers, geographical complex, circumstances in Tianshan Mountains and Gandise Mountains areas. Yersinia pestis were limited to separateness, evoluted only in certain areas to form a great many gene types.

The strains of Yersinia pestis isolated in different period and different natural foci in China were analyzed.Traditional and molecular biological methods were used. Rhamnose fermentation, rRNA gene copy number, nitrite reduction, and the glycerol fermentation were important characters for typing, and pulse field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD) profile could reflect the genetic distance between the strains.The strains could be divided into 15 genetic types by those 6 characters with each of them covered an isolated geographical territories.The characters of strains were described; the genetic relationship of different types, their evolution, and the forming and shift of plague natural foci were analyzed.

The green microalga Chlorella protothecoides was grown heterotrophically in batch mode in a 3.7-L fermenter containing 40 g/L glucose and 3.6 g/L urea. In the late exponential phase, concentrated nutrients containing glucose and urea were fed into the culture, in which the nitrogen source was sufficient compared to carbon source. As a result, a maximum cell dry weight concentration of 48 g/L was achieved. This cell dry weight concentration was 28.4 g/L higher than that obtained in batch culture under the same growth conditions. In another cultivation run, the culture was provided with the same initial concentrations of glucose (40 g/L) and urea (3.6 g/L) as in the batch mode, followed by a relatively reduced supply of nitrogen source in the fed-batch mode to establish a nitrogen-limited culture. Such a modification resulted in an enhanced lutein production without significantly lowering biomass production. The cellular lutein content was 0.27 mg/g higher than that obtained in the N-sufficient culture. The improvements were also reflected by higher maximum lutein yield, lutein productivity, and lutein yield coefficient on glucose. This N-limited fed-batch culture was successfully scaled up from 3.7 L to 30 L, and a three-step cultivation process was developed for the high-yield production of lutein. The maximum cell dry weight concentration (45.8 g/L) achieved in the large fermenter (30 L) was comparable to that in the small one (3.7 L). The maintenance of the culture at a higher temperature (i.e., 32 degrees C) for 84 h resulted in a 19.9% increase in lutein content but a 13.6% decrease in cell dry weight concentration as compared to the fed-batch culture (30 L) without such a treatment. The enhancement of lutein production resulted from the combination of nitrogen limitation and high-temperature stress.

The effects of nitrate, ammonium, and urea as nitrogen sources on the heterotrophic growth of Chlorella protothecoides were investigated using flask cultures. No appreciable inhibitory effect on the algal growth was observed over a nitrogen concentration range of 0.85-1.7 g l(-)(1). In contrast, differences in specific growth rate and biomass production were found among the cultures with the various nitrogen compounds. The influence of different nitrogen sources at a concentration equivalent to 1.7 g l(-)(1) nitrogen on the heterotrophic production of biomass and lutein by C. protothecoides was investigated using the culture medium containing 40 g l(-)(1) glucose as the sole carbon and energy source in fermentors. The maximum biomass concentrations in the three cultures with nitrate, ammonium, and urea were 18.4, 18.9, and 19.6 g l(-)(1) dry cells, respectively. The maximum lutein yields in these cultures were between 68.42 and 83.81 mg l(-)(1). The highest yields of both biomass and lutein were achieved in the culture with urea. It was therefore concluded that urea was the best nitrogen source for the production of biomass and lutein. Based on the experimental results, a group of kinetic models describing cell growth, lutein production, and glucose and nitrogen consumption were proposed and a satisfactory fit was found between the experimental results and predicted values. Dynamic analysis of models demonstrated that enhancing initial nitrogen concentration in fermentor cultures, which correspondingly enhances cell growth and lutein formation, may shorten the fermentation cycle by 25-46%.