Quantitative metabolomics based on gas chromatography mass spectrometry: Status and perspectives

Metabolomics involves the unbiased quantitative and qualitative analysis of the complete set of metabolites present in cells, body fluids and tissues (the metabolome). By analyzing differences between metabolomes using biostatistics (multivariate data analysis; pattern recognition), metabolites relevant to a specific phenotypic characteristic...

Dynamic metabolomic data analysis: A tutorial review

In metabolomics, time-resolved, dynamic or temporal data is more and more collected. The number of methods to analyze such data, however, is very limited and in most cases the dynamic nature of the data is not even taken into account. This paper reviews current methods in use for analyzing dynamic metabolomic data. Moreover, some methods from...

Analyzing longitudinal microbial metabolomics data

A longitudinal experimental design in combination with metabolomics and multiway data analysis is a powerful approach in the identification of metabolites whose correlation with bioproduct formation shows a shift in time. In this paper, a strategy is presented for the analysis of longitudinal microbial metabolomics data, which was performed in...

Prediction of texture perception of mayonnaises from rheological and novel instrumental measurements

Commercial and model mayonnaises varying in fat content and type and amount of thickener were characterized by sensory analysis, rheological measurements and novel instrumental measurements covering other physicochemical properties and/or reflecting changes of food properties during oral processing. Predictions of texture attributes by...

Analytical error reduction using single point calibration for accurate and precise metabolomic phenotyping

Analytical errors caused by suboptimal performance of the chosen platform for a number of metabolites and instrumental drift are a major issue in large-scale metabolomics studies. Especially for MS-based methods, which are gaining common ground within metabolomics, it is difficult to control the analytical data quality without the availability...

Comprehensive analysis of the metabolome of Pseudomonas putida S12 grown on different carbon sources

Metabolomics is an emerging, powerful, functional genomics technology that involves the comparative non-targeted analysis of the complete set of metabolites in an organism. We have set-up a robust quantitative metabolomics platform that allows the analysis of 'snapshot' metabolomes. In this study, we have applied this platform for the...

Quenching of microbial samples for increased reliability of microarray data

Messenger RNA levels change on a minutes scale due to both degradation and de novo transcription. Consequently, alterations in the transcript profiles that are not representative for the condition of interest are easily introduced during sample harvesting and work-up. In order to avoid these unwanted changes we have validated a - 45°C methanol...

Multivariate analysis of microarray data by principal component discriminant analysis: Prioritizing relevant transcripts linked to the degradation of different carbohydrates in Pseudomonas putida S12

The value of the multivariate data analysis tools principal component analysis (PCA) and principal component discriminant analysis (PCDA) for prioritizing leads generated by microarrays was evaluated. To this end, Pseudomonas putida S12 was grown in independent triplicate fermentations on four different carbon sources, i.e. fructose, glucose,...

Inulins improve sensoric and textural properties of low-fat yoghurts

In this study we investigated in detail the effects of the addition of inulins to the sensoric properties of low-fat yoghurts. Yoghurts were prepared from skimmed milk and with different concentrations of inulin (0-4%). Two types of inulin with different chain length of the polymer were used. Attributes contributing to creamy mouthfeel were...

Effects of growth conditions and processing on Rehmannia glutinosa using fingerprint strategy

Metabolite profiling in combination with multivariate statistics is a sophisticated method for quality assessment of natural products. For the development of a quality control strategy in Traditional Chinese Medicine (TCM), we have measured the metabolite fingerprints of Rehmannia glutinosa by GC-MS. Plants were grown under different climate and...

Sensory sub-attributes of creamy mouthfeel in commercial mayonnaises, custard desserts and sauces

The sensory components of creamy mouthfeel in commercial mayonnaises, custard desserts and sauces were determined, using multi-variate analysis of the mean sensory ratings obtained from a quantitative descriptive analysis (QDA) panel. Creamy is a particularly interesting attribute, as it is generally well correlated with consumer preference....

Quality chain modeling: Meten = sturen

Relating the sensory sensation 'creamy mouthfeel' in custards to rheological measurements

Characteristics of food products are commonly assessed in series of sensory studies to gain insight which can be used, for instance, for product development. Sensory studies are very time-consuming and susceptible to large sources of variation. Assessing information about (new) products by means of instrumental measurements would be very...

Microbial metabolomics: Replacing trial-and-error by the unbiased selection and ranking of targets

Microbial production strains are currently improved using a combination of random and targeted approaches. In the case of a targeted approach, potential bottlenecks, feed-back inhibition, and side-routes are removed, and other processes of interest are targeted by overexpressing or knocking-out the gene(s) of interest. To date, the selection of...

Fusion of mass spectrometry-based metabolomics data

A general method is presented for combining mass spectrometry-based metabolomics data. Such data are becoming more and more abundant, and proper tools for fusing these types of data sets are needed. Fusion of metabolomics data leads to a comprehensive view on the metabolome of an organism or biological system. The ideas presented draw upon...

Identification of disease- and nutrient-related metabolic fingerprints in osteoarthritic guinea pigs

Osteoarthritis (OA), one of the most common diseases among the elderly, is characterized by the progressive destruction of joint tissues. Its etiology is largely unclear and no effective disease-modifying treatment is currently available. Metabolic fingerprinting provides a novel tool for the identification of biomarkers. A metabolic fingerprint...

A systematic quantification of the sources of variation of process analytical measurements in the steel industry