Metabolomics FAQ

• • How Are Allosteric and Chemical Modification Regulations Demonstrated in Carbohydrate Metabolism?

  Allosteric regulation and chemical modification are two fundamental mechanisms governing enzyme activity in carbohydrate metabolism. These regulatory processes are essential for maintaining carbohydrate homeostasis in living organisms.   Allosteric regulation involves enzyme modulation at a site distinct from the active site. In this process, a regulatory molecule binds to an allosteric site, inducing conformational changes that alter enzyme activity. In glycolysis, phosphofructokinase-1 (PFK-1) serve......

• • What Are the Key Steps in DEAE Column Chromatography and Polysaccharide Purification?

  Key Steps in DEAE Column Chromatography 1. Column Preparation (1) Pack the DEAE resin into the chromatography column and equilibrate it using an appropriate buffer to establish a stable ionic environment. (2) Prepare the sample by dissolving or suspending it in a compatible buffer to maintain stability during separation.   2. Sample Application Carefully load the prepared sample onto the equilibrated DEAE column, allowing ionic interactions between the target molecules and the resin.   3. Removal of N......

• • How to Analyze Non-Targeted Metabolomics Results?

  Analyzing non-targeted metabolomics results is a complex process that involves a series of bioinformatics steps:   Data Preprocessing 1. Data Cleaning Remove noise and irrelevant information.   2. Peak Detection and Alignment Detect metabolite peaks and align them across samples.   3. Normalization and Standardization Eliminate variability caused by experimental conditions or instrument differences.   Feature Selection and Dimensionality Reduction: 1. Principal Component Analysis (PCA) Reduce data dim......

• • What Are the Key Steps in Serum Metabolomics Analysis?

  Serum metabolomics analysis is a powerful approach for profiling metabolites in serum samples, widely applied in biomarker discovery, disease diagnosis, and biomedical research. The workflow generally consists of the following steps:   1. Sample Collection and Preparation Blood samples are collected from individuals and processed by centrifugation to isolate the serum. To preserve metabolite stability, the serum samples must be stored under controlled conditions, such as low temperatures or in the pre......

• • What Are the Methods for Extracting Bacterial Cell Membrane Lipids?

  The extraction of bacterial cell membrane lipids involves a series of critical steps, including cell disruption, lipid extraction, and purification. The detailed methodology is outlined below.   1. Cell Collection and Preprocessing (1) Bacterial Cultivation: Grow bacterial cultures until they reach the desired growth phase. (2) Cell Harvesting: Collect bacterial cells via centrifugation or filtration. (3) Cell Washing: Wash the collected cells with an appropriate buffer, such as phosphate-buffered sal......

• • What Are the Three Structural Forms of Flavonoids?

  Flavonoids, a diverse class of polyphenolic compounds, primarily occur in three structural forms:   Flavonols Flavonols represent a subclass of flavonoids distinguished by a hydroxyl (-OH) group at the C-4 position. These compounds are abundant in nature and play significant roles in plant defense and human health. Common flavonols include quercetin, rutin, and quercetin-3-O-glucuronide, which are predominantly found in vegetables, fruits, and tea.   Flavonoid Glycosides Flavonoid glycosides are flavo......

• • How to Establish a Polysaccharide Standard Curve via the Phenol-Sulfuric Acid Method? Why No Color or Stable UV Absorbance?

  The phenol-sulfuric acid method is a widely used technique for quantifying polysaccharides by measuring the absorbance of chromogenic products formed through the reaction between polysaccharides and phenol under acidic conditions. A critical aspect of this method is the establishment of a standard curve for accurate quantification. The detailed procedure is outlined below:   1. Selection of Standard Substance A purified monosaccharide or polysaccharide, such as glucose or glycoprotein, is typically us......

• • Are Gut Microbes Detectable in Feces After 3 Years at -80°C? Does Storage Impact Microbial Composition or Serum Metabolomics?

  1. Stability of Fecal Samples for Gut Microbiota Analysis Freezing fecal samples at -80°C is a widely accepted method for preserving bacterial DNA in microbiome research. Even after three years of storage, DNA degradation remains minimal under these conditions, allowing for reliable microbial detection. However, prolonged storage may influence microbial composition, particularly for taxa sensitive to freeze-thaw cycles, potentially affecting downstream analyses.   2. Stability of Serum Samples for Unt......

• • What Methods Can Be Used to Completely Remove Starch from Yam Polysaccharides?

  To completely remove starch from yam and ensure the extraction of only yam polysaccharides, the following methods can be employed:   Enzymatic Degradation Amylases, such as α-amylase, can selectively degrade starch without affecting other polysaccharides. Incubate the sample under suitable temperature and pH conditions to allow the amylase to act for a specified period, after which the degradation products can be removed through centrifugation and filtration.   Alcohol Precipitation Polysaccharides an......

• • What Are the Key Differences Between Untargeted Lipidomics and Untargeted Metabolomics?

  Untargeted lipidomics and untargeted metabolomics are two distinct global profiling approaches used to comprehensively study lipids and metabolites in biological systems.   Untargeted lipidomics enables qualitative and quantitative characterization of lipid composition and alterations, primarily using mass spectrometry-based techniques to analyze complex lipid mixtures. This approach involves sample extraction, ionization, and spectral analysis. By evaluating differences in spectral data across sample......