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Chang CC, Chen YH, Chang WR, Wu CH, Chen YH, Chang CY, Yuan MH, Shie JL, Li YS, Chiang SW, Yang TY, Lin FC, Ko CH, Liu BL, Liu KW, Wang SG. The emissions from co-firing of biomass and torrefied biomass with coal in a chain-grate steam boiler. J Air Waste Manag Assoc 2019; 69:1467-1478. [PMID: 31524083 DOI: 10.1080/10962247.2019.1668871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 07/16/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
In this study, biomass of rice straw (RS) and wood (WD) and their torrefied biomass (RST and WDT) were used as solid biofuel (SBF) for co-firing individually with coal in a commercial continuous chain-grate steam boiler system, which was conducted at fixed input rate of heating value of mixture of SBF and coal and at fixed airflow rate. The effects of key system parameters on the gaseous and particulate pollutions and ash were examined. These include SBF type and blending ratio (RBL) of biomass (i.e., SBF) in the mixture of coal and biomass based on heating values for co-firing.The results indicated that wood, which possesses high heating value while less amount of ash, is more suitable for co-firing with coal than rice straw. Torrefaction can increase the heating value of biomass and homogenize its property, being beneficial to co-firing. Also, torrefaction can decompose the hydroxyl group of biomass, which makes biomass tending to possess hydrophobicity. This, in turn, helps the storage and transportation of biomass. Generally, adding the RS (with RBL = 5-10%), WD (2-15%), RST (2-10%) and WDT (2-20%), respectively, with coal decreases the emissions of NOx and SO2, but increases that of CO (except RST). The emission of HCl is little. The addition of biomass also increases the emission of fine particulate matters (PM) especially PM2.5 in the flue gases, raising PM2.5/PM100 from 34.87 to 78.35 wt.% (Case 50%WDT). These emissions for the Cases tested satisfy with Taiwanese emission standards of stationary sources which set limitations of NOx, SO2, CO and HCl < 350, 300, 2000 and 80 ppmv, while PM < 50 mg/m3, respectively. The results support the use of RS, WD, RST and WDT for co-firing with coal.Implications: This study examined the suitability of using solid bio-fuels to co-fire with coal in an industrial chain-grate steam boiler system with a capacity of 100 kW, in order to achieve carbon-free emissions. Both biomass and torrefied biomass of solid bio-fuel were tested. The findings would be useful for proper design and rational operation of solid bio-fuel/coal co-firing combustion matching the appeal of sustainable material management and circular economy of biomass, and of adaptation of global warming induced by greenhouse gases. It also provides information for policy-makers to promote the co-firing application of biomass and related bio-waste materials.
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Affiliation(s)
- Chia-Chi Chang
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
| | - Yen-Hau Chen
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
| | - Wei-Ren Chang
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
| | - Chao-Hsiung Wu
- Department of Environmental Engineering, Da-Yeh University, Changhua, Republic of China
| | - Yi-Hung Chen
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Republic of China
| | - Ching-Yuan Chang
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
- Department of Chemical Engineering, National Taiwan University, Taipei, Republic of China
| | - Min-Hao Yuan
- Department of Occupational Safety and Health, China Medical University, Taichung, Republic of China
| | - Je-Lueng Shie
- Department of Environmental Engineering, National I-Lan University, Yi-Lan, Republic of China
| | - Yuan-Shen Li
- Department of Environmental Engineering, National I-Lan University, Yi-Lan, Republic of China
| | - Sheng-Wei Chiang
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
| | - Tzu-Yi Yang
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
| | - Far-Ching Lin
- School of Forestry and Resource Conservation, National Taiwan University, Taipei, Republic of China
| | - Chun-Han Ko
- School of Forestry and Resource Conservation, National Taiwan University, Taipei, Republic of China
| | - Bo-Liang Liu
- Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Republic of China
| | - Kuang-Wei Liu
- Environmental Analysis Laboratory, Environmental Protection Administration, Chung-Li, Republic of China
| | - Shi-Guan Wang
- Environmental Analysis Laboratory, Environmental Protection Administration, Chung-Li, Republic of China
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Verma SK, Chang WR, Lombardi DA, Courtney TK, Huang YH, Brennan MJ, Perry MJ. USE OF NESTED CASE-CROSSOVER STUDY WITHIN A PROSPECTIVE COHORT STUDY TO EXAMINE BOTH FIXED AND TRANSIENT RISK FACTORS FOR SLIPPING. Inj Prev 2012. [DOI: 10.1136/injuryprev-2012-040580b.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Chang WR. The future of hip arthroplasty: a trainee's perspective. Surgeon 2006; 4:91-2. [PMID: 16623165 DOI: 10.1016/s1479-666x(06)80037-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
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Diao JS, Wan ZL, Chang WR, Liang DC. Structure of monomeric porcine DesB1-B2 despentapeptide (B26-B30) insulin at 1.65 A resolution. Acta Crystallogr D Biol Crystallogr 2005; 53:507-12. [PMID: 15299880 DOI: 10.1107/s0907444997004034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Insulin has a concentration of 10(-8)-10(-11) M in the blood which ensures that it circulates and exerts its physiological functions in vivo as a monomer. The crystal structure of monomeric porcine desB1-B2 despentapeptide (B26-B30) insulin (DesB1-2 DPI) with M(r) = 4934 Da has been determined at 1.65 A resolution using the molecular replacement method. A structural comparison between DesB1-2 DPI and 2Zn insulin reveals that the conformation of DesB1-2 DPI is more similar to molecule I than molecule II of 2Zn insulin. The remarkable conformational difference between B25-Phe in DesB1-2 DPI and B25-Phe in despentapeptide (B26-B30) insulin (DPI) indicates that the residue B25-Phe possesses great flexibility and mobility.
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Affiliation(s)
- J S Diao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
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Chen JC, Chang WR, Shih TS, Chen CJ, Chang WP, Dennerlein JT, Ryan LM, Christiani DC. Predictors of whole-body vibration levels among urban taxi drivers. Ergonomics 2003; 46:1075-1090. [PMID: 12850932 DOI: 10.1080/0014013031000109205] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
To identify a set of important WBV predictors that could be used to develop a statistical instrument for exposure assessment in a large epidemiologic study, a total of 432 WBV measures were taken from a sample of 247 male drivers in Taipei City, Taiwan. In accordance with the ISO 2631-1 (1997) methods, we measured the frequency-weighted vertical acceleration (z-axis) over drivers' seat surface, under conditions representing different types of rides (vacant vs. short vs. long) assigned to random destinations. Mixed effect models were used to analyse the WBV data including repeated measures. For this group of urban taxi drivers regularly exposed to WBV of low intensity (mean = 0.31 ms( - 2), ranging from 0.17 to 0.55 ms( - 2) r.m.s.), our analyses indicated that average driving speed was the primary predictor (p < 0.0001). As average driving speed increased, measured vertical acceleration increased in a quadratic-linear manner (p < 0.0001). Other WBV predictors, after adjusting for the effects of other covariates, included automobile manufacturer (p = 0.02), engine size (p = 0.04), body weight (p = 0.002), age (p = 0.02), use of seat cushion (p = 0.03), and traffic period (p = 0.02). Our study suggests that a similar statistical approach could be employed in future studies to improve the quality and efficiency of WBV exposure assessment in professional drivers.
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Affiliation(s)
- J C Chen
- Occupational Health Program, Department of Environmental Health Harvard School of Public Health, Boston, MA 02115, USA
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Gu YX, Chang WR, Jiang T, Zheng CD, Fan HF. Direct-method-aided phasing of MIR diffraction data from proteins. Acta Crystallogr A 2002; 58:547-51. [PMID: 12388872 DOI: 10.1107/s0108767302013922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2002] [Accepted: 08/05/2002] [Indexed: 11/11/2022] Open
Abstract
Direct methods have successfully been used to break the phase ambiguity intrinsic in the single isomorphous replacement (SIR) data of proteins. Based on this, the procedure 'direct-method-aided MIR phasing' (DMIR) has been proposed and applied to the four-derivative multiple isomorphous replacement (MIR) data of a known protein containing 682 amino acid residuals in the asymmetric unit. The data set consists of 14,500 unique reflections at 3 A resolution with F(obs.) greater than 2sigma. Test calculation showed that the phases from conventional MIR phasing could be significantly improved by direct methods leading to obvious improvement in the quality of the resultant Fourier maps.
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Affiliation(s)
- Y X Gu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
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Abstract
The slip resistance of 16 commonly used footwear materials was measured with the Brungraber Mark II and the English XL on 3 floor surfaces under surface conditions of dry, wet, oily and oily wet. Three samples were used for each material combination and surface condition. The results of a one way ANOVA analysis indicated that the differences among different samples were statistically significant for a large number of material combinations and surface conditions. The results indicated that the ranking of materials based on their slip resistance values depends highly on the slipmeters, floor surfaces and surface conditions. For contaminated surfaces including wet, oily and oily wet surfaces, the slip resistance obtained with the English XL was usually higher than that measured with the Brungraber Mark II. The correlation coefficients between the slip resistance obtained with these two slipmeters calculated for different surface conditions indicated a strong correlation with statistical significance.
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Affiliation(s)
- W R Chang
- Liberty Mutual Research Center for Safety and Health, Hopkinton, MA 01748, USA.
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He XY, Wang XQ, Yang SJ, Chang WR, Liang DC. Overexpression, purification, crystallization and preliminary crystallographic studies on a thermostable beta-glycosidase from Thermus nonproteolyticus HG102. Acta Crystallogr D Biol Crystallogr 2001; 57:1650-1. [PMID: 11679733 DOI: 10.1107/s090744490101112x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2001] [Accepted: 07/03/2001] [Indexed: 11/10/2022]
Abstract
A thermostable beta-glycosidase (Tn-gly) from Thermus nonproteolyticus HG102 has been cloned and overexpressed in Escherichia coli. The recombinant enzyme, with a molecular mass of 48.9 kDa, was purified to homogeneity. It can hydrolyze a wide range of oligosaccharides and perform transglycosylation. Crystals of the recombinant enzyme were grown by the hanging-drop vapour-diffusion technique with MPD and NaCl as precipitants. They belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 66.7, b = 94.6, c = 176.5 A.
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Affiliation(s)
- X Y He
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
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Grönqvist R, Chang WR, Courtney TK, Leamon TB, Redfern MS, Strandberg L. Measurement of slipperiness: fundamental concepts and definitions. Ergonomics 2001; 44:1102-1117. [PMID: 11794760 DOI: 10.1080/00140130110085529] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The main objective of this paper is to give an overview of basic concepts and definitions of terms related to the 'measurement of slipperiness' from the onset of a foot slide to a gradual loss of balance and a fall. Other unforeseen events prior to falls (e.g. tripping) are sparingly dealt with. The measurement of slipperiness may simply comprise an estimation of slipping hazard exposures that initiate the chain of events ultimately causing an injury. However, there is also a need to consider the human capacity to anticipate slipperiness and adapt to unsafe environments for avoiding a loss of balance and an injury. Biomechanical and human-centred measurements may be utilized for such an approach, including an evaluation of relevant safety criteria for slip/fall avoidance and procedures for validation of slip test devices. Mechanical slip testing approaches have been readily utilized to measure slipperiness in terms of friction or slip resistance but with conflicting outcomes. An improved understanding of the measurement of slipperiness paradigm seems to involve an integration of the methodologies used in several disciplines, among others, injury epidemiology, psychophysics, biomechanics, motor control, materials science and tribology.
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Affiliation(s)
- R Grönqvist
- Finnish Institute of Occupational Health, Department of Physics, Helsinki.
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Chang WR, Grönqvist R, Leclercq S, Myung R, Makkonen L, Strandberg L, Brungraber RJ, Mattke U, Thorpe SC. The role of friction in the measurement of slipperiness, Part 1: friction mechanisms and definition of test conditions. Ergonomics 2001; 44:1217-1232. [PMID: 11794765 DOI: 10.1080/00140130110085574] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Friction has been widely used as a measure of slipperiness. However, controversies around friction measurements remain. The purposes of this paper are to summarize understanding about friction measurement related to slipperiness assessment of shoe and floor interface and to define test conditions based on biomechanical observations. In addition, friction mechanisms at shoe and floor interface on dry, liquid and solid contaminated, and on icy surfaces are discussed. It is concluded that static friction measurement, by the traditional use of a drag-type device, is only suitable for dry and clean surfaces, and dynamic and transition friction methods are needed to properly estimate the potential risk on contaminated surfaces. Furthermore, at least some of the conditions at the shoe/floor interface during actual slip accidents should be replicated as test conditions for friction measurements, such as sliding speed, contact pressure and normal force build-up rate.
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Affiliation(s)
- W R Chang
- Liberty Mutual Research Center for Safety and Health, Hopkinton, MA 01748, USA.
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Chang WR, Grönqvist R, Leclercq S, Brungraber RJ, Mattke U, Strandberg L, Thorpe SC, Myung R, Makkonen L, Courtney TK. The role of friction in the measurement of slipperiness, Part 2: survey of friction measurement devices. Ergonomics 2001; 44:1233-1261. [PMID: 11794766 DOI: 10.1080/00140130110085583] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper seeks to address questions related to friction measurement such as how friction is related to human-centred assessment and actual slipping, and how repeatable friction measurements are. Commonly used devices for slipperiness measurement are surveyed and their characteristics compared with suggested test conditions from biomechanical observations summarized in Part 1. The issues of device validity, repeatability, reproducibility and usability are examined from the published literature. Friction assessment using the mechanical measurement devices described appears generally valid and reliable. However, the validity of most devices could be improved by bringing them within the range of human slipping conditions observed in biomechanical studies. Future studies should clearly describe the performance limitations of any device and its results and should consider whether the device conditions reflect these actual human slipping conditions. There is also a need for validation studies of more devices by walking experiments.
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Affiliation(s)
- W R Chang
- Liberty Mutual Research Center for Safety and Health, Hopkinton, MA 01748, USA.
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Abstract
Surface roughness has been shown to have substantial effects on the slip resistance between shoe heels and floor surfaces under various types of walking environments. This paper summarizes comprehensive views of the current understanding on the roles of surface roughness on the shoe and floor surfaces in the measurement of slipperiness and discusses promising directions for future research. Various techniques and instruments for surface roughness measurements and related roughness parameters are reviewed in depth. It is suggested that a stylus-type profilometer and a laser scanning confocal microscope are the preferred instruments for surface roughness measurements in the field and laboratory, respectively. The need for developing enhanced methods for reliably characterizing the slip resistance properties is highlighted. This could be based on the principal understanding of the nature of shoe and floor interface and surface analysis techniques for characterizing both surfaces of shoe and floor. Therefore, surface roughness on both shoe and floor surfaces should be measured and combined to arrive at the final assessment of slipperiness. While controversies around the friction measurement for slipperiness assessment still remain, surface roughness measurement may provide an objective alternative to overcoming the limitations of friction measurements.
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Affiliation(s)
- W R Chang
- Liberty Mutual Research Center for Safety and Health, Hopkinton, MA 01748, USA.
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Abstract
Occupational slips, trips, and falls (STF) present a tremendous burden on the working people of the world. The precise contribution of slipping to this burden is not completely understood and significant questions exist regarding the definition and measurement of slipperiness. In an attempt to advance slipperiness measurement, a workshop symposium of tribologists, biomechanists, clinicians, engineers, epidemiologists and related scientists was held in order to summarize the state of the science in slipperiness measurement. Organized into issue-focused working groups, participants collaborated on manuscripts addressing conceptual and definitional issues, the contribution of slipperiness to STF injury, and biomechanical, human-centred, and tribological approaches to slipperiness measurement. The conference design, contributions of working groups and outcomes are summarized.
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Affiliation(s)
- T K Courtney
- Liberty Mutual Research Center for Safety and Health, Hopkinton, MA 01748, USA.
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Abstract
The crystal structure of R-phycocyanin from Polysiphonia urceolata (R-PC-PU) at 2.4 A is reported. The R-PC-PU crystal belongs to space group P4(3)2(1)2 with cell parameters a = 135.1 A, c = 210.0 A, and alpha = beta = gamma = 90 degrees. The structure was determined by molecular replacement. The crystallographic R-factor of the refined model is 0.189 (R(free) = 0.239). Comparison of the microenvironment of chromophore beta 155 in R-PC-PU and in C-PC from Fremyolla diphosiphon (C-PC-FD) reveals that their spectral differences may be caused by their different alpha 28 residues. In the R-PC-PU crystal structure, two (alpha beta)(3) trimers assemble face to face to form a hexamer, and two such hexamers assemble in two novel side-to-side arrangements. Possible models for the energy transfer from phycoerythrin to phycocyanin and from phycocyanin to allophycocyanin are proposed based on several phycobiliprotein crystal structures.
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Affiliation(s)
- T Jiang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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Wang XQ, Li LN, Chang WR, Zhang JP, Gui LL, Guo BJ, Liang DC. Structure of C-phycocyanin fromSpirulina platensisat 2.2 Å resolution: a novel monoclinic crystal form for phycobiliproteins in phycobilisomes. Acta Crystallogr D Biol Crystallogr 2001; 57:784-92. [PMID: 11375497 DOI: 10.1107/s0907444901004528] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2000] [Accepted: 03/13/2001] [Indexed: 11/10/2022]
Abstract
The crystal structure of C-phycocyanin from the cyanobacterium S. platensis has been determined at 2.2 A resolution. The crystals belong to the monoclinic crystal form, which has not been previously reported for phycobiliprotein structures. The structure was solved using the molecular-replacement method with a final R value of 18.9% (R(free) = 23.7%) after model building and refinement. In the crystals used for the study, the C-phycocyanin hexamers formed by face-to-face association of two trimers are arranged in layers rather than in columns. Three different kinds of packing between adjacent hexamers in the layer were compared. The tight packing of two adjacent hexamers formed by four trimers in the asymmetric unit brings beta155 PCB chromophores close together, so it is possible that lateral energy transfer takes place through the beta155-beta155 route.
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Affiliation(s)
- X Q Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, People's Republic of China
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Abstract
Surface roughness affects friction, but it is not clear what surface roughness characteristics are better correlated with friction. The average of the maximum height above the mean line in each cut-off length (Rpm) and the arithmetical average of surface slope (deltaa) had the highest correlation with dynamic friction coefficient in a previous study. The previous study was expanded to two different footwear materials and four different contaminants on a porcelain tile in the current investigation. The results showed that dynamic friction decreased as the interface speed and glycerol content in the contaminant were increased due to the hydrodynamic lubrication effect. Deltaa had the highest correlation with friction for most of the test conditions with neolite. For Four S rubber, friction coefficient appeared to have the highest correlation with the parameters related to the surface void volume at 30% glycerol content, related to the surface slope at 70 and 85% glycerol contents, and related to the peak to valley distance at 99% glycerol content. A good indicator of surface slip resistance probably should consist of the surface parameters representing the surface slope, the surface void volume and the surface peak-to-valley distance with the coefficients determined by the system parameters.
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Affiliation(s)
- W R Chang
- Liberty Mutual Research Center for Safety and Health, Hopkinton, MA 01748, USA.
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Wang XQ, Gui LL, Dai Y, Wang CC, Chang WR, Liang DC. Purification, crystallization and preliminary crystallographic studies on the N-terminal fragment of human protein disulfide isomerase. Acta Crystallogr D Biol Crystallogr 1999; 55:1958-60. [PMID: 10531508 DOI: 10.1107/s0907444999011762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A fragment of human protein disulfide isomerase composed of the thioredoxin-like a and b domains (ab) has been expressed in Escherichia coli as a fusion protein with glutathione-S-transferase and purified after thrombin cleavage. Two forms of ab crystal were obtained with polyethylene glycol as precipitant and different additives at pH 7.5. The space group of form I is P4(1)2(1)2 or P4(3)2(1)2, with unit-cell dimensions a = 81.5, c = 259.7 A. The space group of form II is P4(1)22 or P4(3)22, with unit-cell dimensions a = 82.7, c = 86.5 A.
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Affiliation(s)
- X Q Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing 100101, People's Republic of China
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Liu ZJ, Sun YJ, Rose J, Chung YJ, Hsiao CD, Chang WR, Kuo I, Perozich J, Lindahl R, Hempel J, Wang BC. The first structure of an aldehyde dehydrogenase reveals novel interactions between NAD and the Rossmann fold. Nat Struct Biol 1997; 4:317-26. [PMID: 9095201 DOI: 10.1038/nsb0497-317] [Citation(s) in RCA: 255] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The first structure of an aldehyde dehydrogenase (ALDH) is described at 2.6 A resolution. Each subunit of the dimeric enzyme contains an NAD-binding domain, a catalytic domain and a bridging domain. At the interface of these domains is a 15 A long funnel-shaped passage with a 6 x 12 A opening leading to a putative catalytic pocket. A new mode of NAD binding, which differs substantially from the classic beta-alpha-beta binding mode associated with the 'Rossmann fold', is observed which we term the beta-alpha,beta mode. Sequence comparisons of the class 3 ALDH with other ALDHs indicate a similar polypeptide fold, novel NAD-binding mode and catalytic site for this family. A mechanism for enzymatic specificity and activity is postulated.
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Affiliation(s)
- Z J Liu
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens 30602, USA
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Bao SJ, Xie DL, Zhang JP, Chang WR, Liang DC. Crystal structure of desheptapeptide(B24-B30)insulin at 1.6 A resolution: implications for receptor binding. Proc Natl Acad Sci U S A 1997; 94:2975-80. [PMID: 9096331 PMCID: PMC20307 DOI: 10.1073/pnas.94.7.2975] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The crystal structure of desheptapeptide (B24-B30) insulin (DHPI), a virtually inactive analog of insulin, was determined at 1.6 A resolution. In the refined structure model, DHPI retains three alpha-helices (A1-A8, A12-A18, and B9-B19) as its structural framework, while great conformational changes occur in the N and C termini of B-chain. The beta-turn, which lies in B20-B30 in insulin and insulin analogs with high potency, no longer exists in DHPI. Relative motion is observed among the three alpha-helices, each as a rigid functional group. In contrast, a region covering B5-B6 and A6-A11 exhibits a relatively stable conformation. We interpret our results as identifying: (i) the importance of beta-turn in determining the receptor-binding potency of insulin and (ii) a leading role of PheB24 in maintaining the beta-turn structure.
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Affiliation(s)
- S J Bao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing
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Liu ZJ, Hempel J, Sun J, Rose J, Hsiao D, Chang WR, Chung YJ, Kuo I, Lindahl R, Wang BC. Crystal structure of a class 3 aldehyde dehydrogenase at 2.6 A resolution. Adv Exp Med Biol 1997; 414:1-7. [PMID: 9059600 DOI: 10.1007/978-1-4615-5871-2_1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Z J Liu
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens 30602, USA
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Abstract
The structure of R-phycoerythrin (R-PE) from Polysiphonia urceolata was determined at 2.8 A resolution. The crystals belong to space group R3 with unit cell dimensions of a = b = 189.8 A, c = 60.1 A. The subunit composition of R-PE is (alpha 2 beta 2)3 gamma. The three-dimensional structure of R-PE was solved by the multiple isomorphous replacement method. After several cycles of model building and refinement, the crystallographic R-factor of the final model is 18.0% with data from 10.0 to 2.8 A resolution. The four phycoerythrobilin chromophores alpha 84, alpha 140a, beta 84 and beta 155 in an (alpha beta) unit are each covalently bound to a cysteine residue through ring A. The phycourobilin chromophore is bound to cysteine beta 50 by ring A and bound to cysteine beta 61 by ring D. The ring A and ring D of phycourobilin deviate from the conjugate plane formed by ring B and ring C and the four rings form a boat-shaped structure. R-PE contains a 34 kDa gamma subunit that is assumed to lie in the central channel of the molecular disc (alpha 2 beta 2)3. The energy transfer and relationship between cysteine residues and chromophores are discussed.
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Affiliation(s)
- W R Chang
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences, Beijing, China
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23
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Li SG, Gui LL, Lin ZH, Wan ZL, Chang WR, Liang DC. Purification and crystal growth of F1-ATPase from pig heart mitochondria. Biochem Mol Biol Int 1996; 40:479-86. [PMID: 8908356 DOI: 10.1080/15216549600201043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A method has been evolved toward the aim of getting suitable crystals for high resolution of structural analysis of F1-ATPase by X-ray crystallography. The different conditions for crystal growth of ATPase that were isolated and purified by different methods from pig heart mitochondrial ATP synthase had been compared and screened. A simple method for purification of F1-ATPase was adopted. The F1-ATPase is released with chloroform from submitochondrial particles. Then it was treated with fractional precipitation of (NH4)2SO4 and finally was further purified by employing the sephadex G 200 column. The crystals of F1-ATPase were usually obtained after a few months. They appeared to have uniform morphology of tetrahedron. They diffracted to a resolution of 7A. The diffraction data were collected on the XRD-100 Siemens Area Detector. According to a total of 240 frames, the cell parameters obtained are a = b = 147 A, c = 208 A, alpha = beta = gamma = 90 alpha, the probable space group is P4 or its antipode. The reproducibility of this method for crystallization of F1-ATPase is good.
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Affiliation(s)
- S G Li
- Institute of Biophysics, Chinese Academy of Sciences, National Laboratory of Biomacromolecules, Beijing, China
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24
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Abstract
Based on the extensive structural comparisons among the determined structures of the different species and crystal forms of insulin and its derivatives in our laboratory, it was suggested that the binding interaction with the receptor molecule should take place mainly on an amphipathic surface of the insulin molecule. In the middle of this amphipathis surface, there was a hydrophobic surface with an area of about 150 A2, while the polar and charged groups distributing around the hydrophobic surface constructed a hydrophilic zone. The hydrophobic surface was usually covered by the extended B-chain C-terminal peptides with great mobility. The angle between the proposed binding interaction surface and the surface of dimerization was about 20 degrees. The results from studies on structures of A1-(L-Trp) insulin and A1-(D-Trp) insulin confirmed the interaction mechanism model we proposed.
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Affiliation(s)
- D C Liang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, People's Republic of China
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25
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Ren B, Wang DC, Chang WR, Zhang Y, Obermeier R. Studies on long-acting insulin: crystal structure of Arg-B31 human insulin at 2.0A resolution. Sci China B 1993; 36:1501-9. [PMID: 8129837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The crystal structure of Arg-B31 human insulin (ABHI), a long-acting insulin derivative, has been determined at 2.0 A resolution by using X-ray diffraction analysis. The final crystallographic R factor of the structure model after the refinement is 0.189 with the bond length r. m. s deviation of 0.018 A. The refined structure of ABHI showed that the conformation of B-chain C-terminal residues was more stable than that in the native molecule. A striking structural feature of ABHI was an additional ion pair formed between Arg-B31 of molecule I and Glu-B21 of molecule II in a dimer, and three ionic bonds between the neighbouring molecules thereby appeared on the surface of ABHI hexamer. These secondary bonds generated by the insertion of the residue Arg-B31 should make the rate of dissociation of ABHI hexamer slow down when it was injected into the body and the property of protraction should be produced by a 'depot effect'. This ought to be the main structure basis of the prolonged action of ABHI. The results observed here demonstrate that the main idea we used in search for long-acting insulin is reasonable and correct which goes like this: making some additional non-covalent bonds between insulin monomers so as to slow down the dissociation of insulin oligomers and gain the protraction from a 'depot effect', which may be used as a principle in the further research. It also shows an impressive example that the experimental result reported here is in agreement with the theoretical prediction before the structural determination.
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Affiliation(s)
- B Ren
- Institute of Biophysics, Academia Sinica, Beijing, PRC
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26
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Song HW, Chang WR, Liang DC. Studies on the crystal structure of [L-Met]B0 bovine insulin at 3.0A resolution. Sci China B 1993; 36:187-95. [PMID: 8318150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Based on the crystal symmetry of [L-Met]B0 bovine insulin (LMBBI) and the fundamental theory of the molecular packing method, the scheme for the determination of the position and orientation of the molecules by only using one-dimensional rotation and one-dimensional translation was chosen to be used, and therefore the calculation of the rotation function of the molecular replacement method and the refinement of the rotational and translational parameters by using the R-factor search method were simplified greatly. After the preliminary refinement by using the macromolecular rigid body refinement technique, the molecular model was further refined and adjusted by using the energy-minimizing stereochemical-restrained least squares refinement technique assisted by the manual revision on the difference Fourier maps. The L-Met residues on the N-terminus of the B-chain appeared clearly on the final electron density map.
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Affiliation(s)
- H W Song
- Institute of Biophysics, Academia Sinica, Beijing, PRC
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27
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Liang DC, Chang WR, Zhang JP, Wan ZL. The possible mechanism of binding interaction of insulin molecule with its receptor. Sci China B 1992; 35:547-57. [PMID: 1605837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Detailed structural comparisons and investigation of DPI, 2 Zn insulin and some other derivatives of insulin were performed by the least-squares superimposition technique and the graphics technique. It is pointed out in this paper that the binding interaction with the receptor molecule should take place mainly on an amphipathic surface of the insulin molecule. In the middle, there is a hydrophobic surface with an area of about 150 A2 consisting of many hydrophobic residues; while the polar or charged groups distributing around the hydrophobic surface construct a hydrophilic zone. The hydrophobic surface is usually covered by the extended B-chain C-terminal peptides with great mobility and protected from the solvent molecules. The angle between the amphipathic surface and the surface of dimerization is about 20 degrees. The results from the detailed structural comparison between Al-(L-Trp) insulin and Al-(D-Trp) insulin have provided a very good explanation to their great difference in biological activity, and confirmed our proposed binding interaction model of the insulin molecule with its receptor as well.
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Affiliation(s)
- D C Liang
- Institute of Biophysics, Academia Sinica, Beijing, PRC
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28
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Liang DC, Chang WR, Wang DC, Zhang JP. The characteristics and motion model of insulin monomer. Sci China B 1992; 35:418-28. [PMID: 1590917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The extensive conformational comparisons among the determined structures of the different species and crystal forms of insulin and the varied insulin derivatives were performed by using the least-squares superimposition technique and the graphics technique. The results of the investigation showed that the structure of molecule I in 2Zn insulin was closer to that of the natural monomer; the conformational difference between two molecules of a dimer came out during dimerization and it was further improved and stabilized during the hexamerization and packing of hexamers in crystal; through the hinge peptides, such as A10, B4, B8, B24, B20 and B23, there was a flexible relative motion among the structural segments in the insulin molecule, and the residues at the B-chain C-terminal might have a shift of more than 10A; the mobility for each residue side-chain was very different due to the different surroundings.
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Affiliation(s)
- D C Liang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, PRC
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29
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Chen LQ, Rose JP, Breslow E, Yang D, Chang WR, Furey WF, Sax M, Wang BC. Crystal structure of a bovine neurophysin II dipeptide complex at 2.8 A determined from the single-wavelength anomalous scattering signal of an incorporated iodine atom. Proc Natl Acad Sci U S A 1991; 88:4240-4. [PMID: 2034668 PMCID: PMC51634 DOI: 10.1073/pnas.88.10.4240] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The crystal structure of a dipeptide complex of bovine neurophysin II has been solved at 2.8 A resolution solely by using single-wavelength anomalous scattering data from a single iodinated derivative. The asymmetric unit is an elongated tetramer of dimensions 110 x 40 x 30 A, composed of two dimers related by pseudo twofold symmetry. Each monomer consists of two homologous layers, each with four antiparallel beta-strands. The two regions are connected by a helix followed by a long loop. Monomer-monomer contacts involve antiparallel beta-sheet interactions, which form a dimer with two layers of eight beta-strands. One peptide per monomer occupies the principal hormone-binding pocket formed by part of the amino-terminal region and parts of the connecting helix and loop, with binding to protein consistent with conclusions drawn from solution studies. Dimer-dimer contacts involve the Tyr49 region adjacent to this site. A fifth dipeptide, of unknown biological significance, helps to stabilize one of the monomer-monomer interfaces and the tetramer-tetramer network in the crystal.
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Affiliation(s)
- L Q Chen
- Department of Crystallography, University of Pittsburgh, PA 15260
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30
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Chang WR, Chen LQ, Rose J, Wei CH, Abrams L, Sax M, Wang BC. A new crystal form of ricin-OR. Eur J Biochem 1989; 180:327-8. [PMID: 2924767 DOI: 10.1111/j.1432-1033.1989.tb14651.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Ricin-OR, an antitumor toxin, has been crystallized in space group P2 with cell parameters a = 8.77 nm, b = 4.64 nm, c = 7.64 nm and beta = 101 degrees. There is one molecule in the asymmetric unit and the solvent content is estimated to be 48% by volume. The crystals diffract to 0.25 nm resolution which is higher than that of the previously reported C2 crystal form which had a solvent content of 65%.
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Affiliation(s)
- W R Chang
- Department of Crystallography, University of Pittsburgh, PA 15260
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31
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Wang DC, Lu GG, Zhang JP, Xie DL, Chang WR, Lu ZX, Liang DC. Crystal structure determination of desheptapeptide (B24--B30)-insulin. Sci China B 1989; 32:155-65. [PMID: 2673287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Desheptapeptide (B24--B30)-insulin (DHPI), an essentially inactive insulin analog, is crystallized in space group P212121 with two molecules in an asymmetric unit. The orientations of the molecules in the crystal cell have been determined by using Patterson search method at 6 A resolution and the positions of the molecules are deduced from translation function calculation and R search at 3 A resolution. After using the rigid body refinement (CORELS) further to refine the orientational and positional parameters as well as the initial energy restrained refinement (EREF) for the model, the crystallographic R value is reduced to 0.384 at 3 A resolution. The initial Fourier map shows that the B-chain N-terminal (B1-B8) and C-terminal (B20-B22) segments, compared with the native 2 zinc insulin, exhibit drastic conformational changes, but the three helices of B- and A-chains and their relative arrangement are essentially kept in DHPI.
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Affiliation(s)
- D C Wang
- Institute of Biophysics, Academia Sinica, Beijing
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32
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Su YC, Chiu RJ, Yu N, Chang WR. The microbial production of amylase inhibitor and its application. I. Isolation and cultivation of Streptomyces nigrifaciens NTU-3314. Proc Natl Sci Counc Repub China B 1984; 8:292-301. [PMID: 6086001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In the course of screening amylase inhibitor producing, microorganisms, a strain identified as Streptomyces nigrifaciens NTU-3314 was found to have the highest inhibitor-producing ability among the other isolated strains. This strain was aerobically cultured at 30 degrees C in a 5l jar fermentor with a working volume of 2l. The optimum cultural medium consisted of defatted soybean flake 3.0%, potato starch 4.0%, casein 0.6%, sucrose 0.6%, serine 0.02% and NaCl 0.8% (pH 7.0). With an aeration rate of 1.5 vvm, an agitation speed of 300 rpm and an inoculum of 15% seed (previously grown in seed medium 3), the highest amount of inhibitor was obtained after 24 hours of cultivation. The amylase inhibitor produced had inhibitory effects on both alpha-amylase and glucoamylase, but not on beta-amylase, alpha-glucosidase, beta-glucosidase or dextranase. It was quite stable in 0.1M phosphate buffer (pH 7.0) and nearly 100% of its activity was retained even after boiling at 100 degrees C for 20 min.
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