α-amylase is an endonucleoside hydrolase that hydrolyzes the α-1, 4-glycosidic bonds inside polysaccharides, such as starch, to generate oligosaccharides, dextrins, maltotriose, maltose and a small amount of glucose. Due to the importance of α-amylase in food industry, human health monitoring and pharmaceuticals, detection of its activity is widely required in the breeding of α-amylase producing strains, in vitro diagnosis, development of diabetes drugs, and the control of food quality. In recent years, many new α-amylase detection methods have been developed with improved speed and sensitivity. This review summarized recent processes in the development and applications of new α-amylase detection methods. The major principle of these detection methods were introduced, and their advantages and disadvantages were compared to facilitate future development and applications of α-amylase detection methods.
Humans ; alpha-Amylases/chemistry* ; Polysaccharides ; Oligosaccharides ; Starch ; Maltose

The robust capacity of skeletal muscle stem cells (SkMSCs, or satellite cells) to regenerate into new muscles in vivo has offered promising therapeutic options for the treatment of degenerative muscle diseases. However, the practical use of SkMSCs to treat muscle diseases is limited, owing to their inability to expand in vitro under defined cultivation conditions without loss of engraftment efficiency. To develop an optimal cultivation condition for SkMSCs, we investigated the behavior of SkMSCs on synthetic maltose-binding protein (MBP)-fibroblast growth factor 2 (FGF2)-immobilized matrix in vitro. We found that the chemically well-defined, xeno-free MBP-FGF2-immobilized matrix effectively supports SkMSC growth without reducing their differentiation potential in vitro. Our data highlights the possible application of the MBP-FGF2 matrix for SkMSC expansion in vitro.
In Vitro Techniques ; Maltose-Binding Proteins ; Muscle, Skeletal ; Muscles ; Stem Cells

BACKGROUND/OBJECTIVES: Fasting and postprandial hyperglycemia should be controlled to avoid complications of diabetes mellitus. This study investigated the effects of autumn olive (Elaeagnus umbellata Thunb.) berry (AOB) on fasting and postprandial hyperglycemia in mice. MATERIALS/METHODS: In vitro α-glucosidase inhibitory effect of AOB was determined. Maltose solution (2 g/kg) with and without AOB extract at 500 mg/kg or acarbose at 50 mg/kg was orally administered to normal mice after overnight fasting and glucose levels were measured. To study the effects of chronic consumption of AOB, db/db mice received the basal diet or a diet containing AOB extract at 0.4% or 0.8%, or acarbose at 0.04% for 7 weeks. Blood glycated hemoglobin and serum glucose and insulin levels were measured. Expression of adiponectin protein in epididymal white adipose tissue was determined by Western blotting. RESULTS: In vitro inhibitory effect of AOB extract on α-glucosidase was 92% as strong as that of acarbose. The AOB extract (500 mg/kg) or acarbose (50 mg/kg) significantly suppressed the postprandial rise of blood glucose after maltose challenge and the area under the glycemic response curve in normal mice. The AOB extract at 0.4% or 0.8% of diet or acarbose at 0.04% of diet significantly lowered levels of serum glucose and blood glycated hemoglobin and homeostasis model assessment for insulin resistance values in db/db mice. The expression of adiponectin protein in adipose tissue was significantly elevated by the consumption of AOB at 0.8% of diet. CONCLUSIONS: Autumn olive (E. umbellata Thunb.) berry may reduce postprandial hyperglycemia by inhibiting α-glucosidase in normal mice. Chronic consumption of AOB may alleviate fasting hyperglycemia in db/db mice partly by inhibiting α-glucosidase and upregulating adiponectin expression.
Acarbose ; Adiponectin ; Adipose Tissue ; Adipose Tissue, White ; Animals ; Blood Glucose ; Blotting, Western ; Diabetes Complications ; Diabetes Mellitus ; Diet ; Fasting ; Fruit ; Glucose ; Hemoglobin A, Glycosylated ; Homeostasis ; Hyperglycemia ; In Vitro Techniques ; Insulin ; Insulin Resistance ; Maltose ; Mice ; Olea

No abstract available.
Ascorbic Acid/*chemistry ; Blood Chemical Analysis/instrumentation/*methods ; Blood Glucose/*analysis ; Maltose/*chemistry

OBJECTIVE1H-NMR technology was carried out to investigate the chemical difference between 30 batches of Cibotium baronetz decoction pieces and look for new method for quality control of C. baronetz decoction pieces.

METHODSix hundreds MHz H-NMR spectroscopy and principle component analysis (PCA) were used to discriminate between 30 batches of commercially available cibotium samples based on multi-component metabolite profiles.

RESULTSaccharide is the principle component of C. baronetz decoction pieces, and steroid and triterpene were the discriminately chemical component. Protocatechuic acid, protocatechuic aldehyde, cibotiumbaroside A, cibotiumbaroside B and 4-O-caffeoyl-D-glucoside could be used as the marker for controlling the quality of commercial C. baronetz decoction pieces.

CONCLUSIONPattern-recognition techniques applied to proton nuclear magnetic resonance (1H-NMR) spectra of 80% methanol extraction of C. baronetz could correctly discriminate not only the quality, but also the chemical component for batches of commercial C. baronetz decoction pieces.

Benzaldehydes ; chemistry ; Caffeic Acids ; chemistry ; Catechols ; chemistry ; Drugs, Chinese Herbal ; chemistry ; standards ; Ferns ; chemistry ; Furans ; chemistry ; Glucose ; chemistry ; Glucosides ; chemistry ; Glycosides ; chemistry ; Hydroxybenzoates ; chemistry ; Magnetic Resonance Spectroscopy ; methods ; Maltose ; chemistry ; Quality Control ; Steroids ; chemistry ; Sucrose ; chemistry ; Triterpenes ; chemistry

BACKGROUND: Self-monitoring of blood glucose levels is recommended for all diabetic patients who receive insulin treatment, because such monitoring of glucose levels may aid in achieving better control in type II diabetes. Further, the use of point-of-care (POC) blood glucose testing in hospitals has increased substantially. In the present study, we validated the performance of ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip (Roche Diagnostics, Germany). METHODS: We evaluated the precision, accuracy, and maltose interference of the ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip. Further, precision was evaluated using dedicated quality control (QC) and Bio-Rad Whole Blood (WB) QC materials (Meter Trax(TM) Control; Bio-Rad, USA). Forty samples were used to compare the results obtained using the ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip with those obtained using the clinical chemistry analyzer Hitachi 7600 (Hitachi, Japan). Maltose interference was assessed at 2 glucose concentration levels at 3 maltose concentration levels. RESULTS: For each concentration level of control materials, within-run coefficient of variation (CV) and total CV obtained were less than 5%. Good correlation was obtained using the Hitachi 7600 (y = 1.02x - 0.18; r 2 = 0.996; N = 40). Effects of maltose interference were less than 10%. CONCLUSIONS: Thus, the ACCU-CHEK(R) systems show good precision and correlation with the routine clinical chemistry analyzer and allow only minimal effects of maltose interference.
Blood Glucose ; Chemistry, Clinical ; Glucose ; Humans ; Insulin ; Maltose ; Quality Control

To understand the effects of sugar whose uptake is dependent or independent on the phosphotransferase system (PTS), two-stage culture of Escherichia coli strain NZN111 that was constructed by disruption of IdhA and pflB encoding the fermentative lactate dehydrogenase (LDH) and pyruvate: formate lyase (PFL) of E. coli W1485, was carried out for organic acids production. When NZN111 was aerobically cultured on fructose (PTS dependent) or maltose (PTS independent), it fermented glucose with succinic acid and pyruvic acid as the major products in subsequent anaerobic culture. The experiments were also performed in a 5-L fermentor. The yields of succinic acid by the fructose-and maltose-grown NZN111 were 0.84 and 0.75 mol/mol, whereas the yields of pyruvic acid were 0.65 and 0.83 mol/mol, respectively. The final ratio of succinic acid to pyruvic acid in the anaerobic stage reached 1.73:1 and 1.21:1, respectively. The different behaviors in anaerobic fermentation by the fructose-, maltose- and glucose-grown NZN111 were likely caused by the regulation of catabolite repression in the aerobic culture stage.
Aerobiosis ; Anaerobiosis ; Carbon ; metabolism ; Escherichia coli ; classification ; metabolism ; Fermentation ; Fructose ; metabolism ; Maltose ; metabolism ; Phosphotransferases ; metabolism ; Pyruvic Acid ; metabolism ; Succinic Acid ; metabolism

To efficiently produce non-specific nuclease (NU) of Serratia marcescens through recombinant overexpression approach and to characterize the purified NU. The nuclease gene was amplified from the genomic DNA of Serratia marcescens by PCR and fused into vector pMAL-c4X with maltose binding protein (MBP) tag. The recombinant vector verified by DNA sequencing was transformed into Escherichia coli BL21. The expressed MBP-NU was purified through the amylose resin and its catalytic characters were analyzed. The results showed the NU gene had 97% identities with the reported S. marcescens nuclease gene and intracellularly expressed in E. coli BL21. The optimal expression conditions were 37 degrees C, 0.75 mmol/L IPTG with 1.5 h induction. The purified MBP-NU exhibited non-specific nuclease activity, able to degrade various nucleic acids, including RNA, single-stranded DNA and double-stranded DNA that was circular or linear. Its optimal temperature was 37 degrees C and optimal pH 8.0. From 1 L culture broth 10.8 mg NU could be purified with a specific activity of 1.11x10(6) U/mg. The catalytic activity of NU was not inhibited by reagents such as EDTA (0.5 mmol/L), PMSF (1 mmol/L) and KCl (150 mmol/L) commonly used in protein purification.
Base Sequence ; Endodeoxyribonucleases ; biosynthesis ; genetics ; Endoribonucleases ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Maltose-Binding Proteins ; genetics ; Molecular Sequence Data ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; isolation & purification ; Serratia marcescens ; enzymology

BACKGROUND: The use of point of care glucometer is widely established. However, the reliability of glucometer can vary according to the type of patients tested. Chemical interference with some current glucometer has been observed in patients undergoing peritoneal dialysis. StatStrip(R) (Nova Biomedical, USA) has been designed to compensate for this interference effect. So we compared the analytic performance and interference response of StatStrip(R) to two conventional glucometers. And we also evaluated the interference response with samples in patients undergoing peritoneal dialysis. METHODS: StatStrip(R) and two other glucometers were compared for linearity, imprecision, correlations with Advia 2400(TM) (Bayer Diagnostics, USA). Interference by lactate, maltose, were evaluated. Interferences in 20 samples of patients undergoing peritoneal dialysis were also evaluated. RESULTS: The coefficients of variation (CVs) of within-run precision were 1.70-3.77% and CVs of total precision were 1.98-3.99%. The linearity was R2=0.9776-0.988 (P<0.001). High correlation was found in each glucometer and the Advia 2400(TM). But all the glucometers showed a variable positive or negative bias compared with reference method. Including samples of patients undergoing peritoneal dialysis, maltose did not significantly influence the glucose concentration in StatStrip(R) and one of the conventional glucometers within 20% difference range. Lactate and hematocrit did not significantly influence the glucose concentration in all glucometers. CONCLUSIONS: StatStrip(R) shows good linearity, precision, correlation with the reference method and shows minimal interference effects. Our results indicate that StatStrip(R) also has clinical reliability when used in a peritoneal dialysis setting.
Bias (Epidemiology) ; Blood Glucose ; Glucose ; Hematocrit ; Humans ; Lactic Acid ; Maltose ; Peritoneal Dialysis

OBJECTIVE: To recombinant express hepatoma associated gene(HTA) and pre-test the function of HTA to determine the role of HTA in the development of liver cancer. METHODS: HTA338-616 was amplified from HepG2 cells and cloned into the prokaryotic expression vector pET21a(+)-MBP. The proteins MBP and MBP-HTA were induced, purified by His-tag magnetic bead purification kit and identified by Western blot and ELISA. HepG2 cells were stimulated with MBP or MBP-HTA proteins. MTT assay and colony formation assay were employed to examine the proliferation of these cells and the changes of cell cycle distribution were determined by flow cytometry. RESULTS: The prokaryotic expression plasmid pET21a(+)-MBP-HTA was successfully constructed. We got a 52 kD purified purpose protein.The proliferation of HepG2 cells stimulated with MBP-HTA was significantly higher than those stimulated with MBP and negative controls. HepG2 cells stimulated with MBP-HTA showed significant decrease fraction in G1 phase and increase fraction in S phase, and the cell proliferation was enhanced. CONCLUSION HTA protein can significantly promote the proliferation of HepG2 cells, which may be related to the promotion of G1 phase to S phase.
Base Sequence ; Cell Proliferation ; drug effects ; Escherichia coli ; genetics ; metabolism ; Genes, Neoplasm ; physiology ; Genetic Vectors ; Hep G2 Cells ; Humans ; Maltose-Binding Proteins ; biosynthesis ; genetics ; pharmacology ; Molecular Sequence Data ; Neoplasm Proteins ; biosynthesis ; genetics ; pharmacology ; Open Reading Frames ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; pharmacology