100 assays (50 of each) per kit
Prices exclude VAT
Available for shipping
|Content:||100 assays (50 of each) per kit|
Short term stability: 2-8oC,
Long term stability: See individual component labels
|Stability:||> 2 years under recommended storage conditions|
|Analyte:||Ammonia, L-Asparagine, L-Glutamine|
|Assay Format:||Spectrophotometer, Microplate|
|Linear Range:||0.2 to 7.0 µg of ammonia, or 0.5 to 50 μg of L-asparagine or L-glutamine per assay|
|Limit of Detection:||
0.50 mg/L (L-asparagine),
0.54 mg/L (L-glutamine),
0.06 mg/L (ammonia)
|Reaction Time (min):||~ 20 min|
|Application examples:||Potatoes, potato products, vegetables, cereals and other materials (e.g. biological cultures, samples, etc.).|
|Method recognition:||Novel method|
The L-Asparagine/L-Glutamine/Ammonia test kit is a novel method for the specific, convenient, cost effective and rapid measurement and analysis of L-asparagine, L-glutamine and ammonia as acrylamide precursors in the food industry, or as cell culture media/supernatant components, or in other materials.
Note for Content: The number of manual tests per kit can be doubled if all volumes are halved. This can be readily accommodated using the MegaQuantTM Wave Spectrophotometer (D-MQWAVE).
Browse our complete list of assay test kits.
- Extended cofactors stability. Dissolved cofactors stable for > 1 year at 4oC.
- Very rapid reaction due to use of uninhibited glutamate dehydrogenase
- All enzymes supplied as stabilised suspensions
- Only kit available
- Very cost effective
- All reagents stable for > 2 years after preparation
- Mega-Calc™ software tool is available from our website for hassle-free raw data processing
- Standard included
Effect of added sugars and amino acids on acrylamide formation in white pan bread.
Shen, Y., Chen, G. & Li, Y. (2019). Cereal Chemistry, 96(3), 545-553.
Background and objectives: The products of the Maillard reaction formed from reducing sugars and amino groups are attracting increasing interests as an important dietary antioxidant source. However, acrylamide is also formed during the process, which is a potential carcinogenic substance. The objective of this study was to investigate the effects of various types and amounts of added sugars and amino acids on the formation of acrylamide in white pan bread. Breads were prepared with five sugars (sucrose, glucose, fructose, maltose, and ribose) at three levels (0, 6, and 12 g/100 g flour) and seven amino acids (lysine, alanine, proline, glycine, arginine, threonine, and asparagine) at three levels (0, 0.1 g, and 0.3 g/100 g flour), and the acrylamide content was analyzed by GC‐MS for both the crust and the crumb. Findings: Bread with 6 g/100 g flour fructose had the highest crust acrylamide content of 102.6 μg/kg as compared with other sugars, while the addition of ribose caused the lowest crust acrylamide content (41.0 μg/kg). The addition of asparagine into the bread formula dramatically increased the acrylamide content of crust as expected, while the addition of glycine and proline decreased crust acrylamide. Significant contents of acrylamide were also detected in bread crumbs. Conclusions: Both the type and amount of added sugars and amino acids in bread formulas affect the amount of acrylamide produced in bread products. Significance and novelty: Our study provides a systematic understanding of the effects of added sugars and amino acids on acrylamide formation in wheat bread. This research will benefit industries in developing reduced acrylamide formulas for common bakery products.Hide Abstract
Lecart, B., Jacquet, N., Anseeuw, L., Renier, M., Njeumen, P., Bodson, B., Vanderschuren, H. & Richel, A. (2018). Food Chemistry, In Press.
A new enzymatic methodology is herein proposed to measure free asparagine content in wheat grains and to predict their potential for Maillard reaction products. Our model estimates the acrylamide levels generated during the industrial heat treatment of whole-grain wheat based on free asparagine and glucose measurements. We selected fifteen wheat varieties currently grown in Belgium as benchmark for the present study. While conventional chromatographic methods require a long and tedious multi-step sample preparation, the proposed method takes advantage of being simple and quick. Statistical analysis of free asparagine content indicates that selected wheat varieties can be classified into seven content levels from 0.0149% to 0.0216% of the dry matter. Based on our analysis, the varieties KWS Ozon, Benchmark and Pionier appears to be the most suitable for thermal processing (i.e. cooking applications).Hide Abstract
Weiss, K., Gerstenberger, J., Salzig, D., Mühlebach, M. D., Cichutek, K., Pörtner, R. & Czermak, P. (2015). Engineering in Life Sciences, 15(4), 425-436.
Measles virus (MV) with attenuated pathogenicity has potential as oncolytic agent. However, the clinical translation of this therapy concept has one major hurdle: the production of sufficient amounts of infectious oncolytic MV particles. The current study describes oncolytic MV production in Vero cells grown on microcarrier using serum-free medium. The impact of the number of harvests, cell concentration at infection (CCI), multiplicity of infection (MOI), and temperature on MV production was determined in different production scales/systems (static T-flasks, dynamic spinner, and bioreactor system) and modes (batch, repeated-batch, and perfusion). Cell growth, metabolic, and production kinetics were analyzed. It was found that the number of harvests had the strongest positive impact on MV yield in each production scale, and that high temperatures affected MV yield adversely. Moderate MV titers were produced in T- and spinner flasks at 37°C (~107 TCID50 mL-1, where TCID50 is tissue culture infective doses 50%), but stirred tank reactor (STR) MV production at 37°C yielded up to 10 000-fold lower MV titers. In contrast, at lower temperatures (32°C, 27°C), 1.4 × 107 TCID50 mL-1, were achieved in the STR. Variations in MOI and CCI had almost no influence on MV production yield. The current study improves oncolytic MV production process understanding and identifies process bottlenecks for large-scale production.Hide Abstract