Enrichment Medium Preparation
Enrichment Medium Preparation - Related Videos
07:18
Bone Conditioned Medium: Preparation and Bioassay
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Cited by 13 •
2015
We describe here how to prepare bone-conditioned medium (BCM) and test its activity in vitro.
08:22
Preparation of Mitochondrial Enriched Fractions for Metabolic Analysis in Drosophila
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Mitochondria play central roles in the regulation of metabolism and homeostasis. Subtle changes in mitochondrial metabolism that affect organismal physiology could be difficult to detect in whole organism metabolomics studies. Here we describe an isolation method that enhances the detection of subtle metabolic shifts in Drosophila melanogaster.
03:39
Preparation of Virus-Enriched Suspension Using Stepwise Sucrose Centrifugation
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2026
Source: Vijayraghavan, S. and Kantor, B. A Protocol for the Production of Integrase-deficient Lentiviral Vectors for CRISPR/Cas9-mediated Gene Knockout in Dividing Cells. J. Vis. Exp., (2017)This video demonstrates a two-step ultracentrifugation method using sucrose gradients and cushions to purify and concentrate viral particles from cell culture supernatant. The procedure enables separation based on buoyant density, allowing recovery of intact virus suitable for downstream applications.
09:16
Medium-scale Preparation of Drosophila Embryo Extracts for Proteomic Experiments
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Cited by 4 •
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The goal of this protocol is to provide a straightforward and inexpensive approach to collecting Drosophila embryos at medium scale (0.5-1 g) and preparing protein extracts that can be used in downstream proteomic applications, such as affinity purification-mass spectrometry (AP-MS).
02:48
Preparation of Artificial Sputum Medium to Emulate Cystic Fibrosis Lung Sputum Ex Vivo
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2025
Source: Vieira, J., et al. Design and Development of a Model to Study the Effect of Supplemental Oxygen on the Cystic Fibrosis Airway Microbiome. J. Vis. Exp. (2021).This video demonstrates the preparation of an artificial sputum medium that mimics the viscosity, nutrient composition, and pH of cystic fibrosis lung sputum. The resulting medium provides a physiologically relevant platform for ex vivo studies.
FAQs
Selection arises from the combined effects of nutrient availability, pH, osmotic conditions, oxygen availability, and inhibitory components. A formulation can support the physiological requirements of the desired population while making conditions less favorable for competing organisms or unwanted cells. Balancing these factors helps increase the target population’s relative representation in a mixed sample without relying on a single selective pressure.
pH, osmotic conditions, oxygen availability, nutrient composition, and inhibitory components each influence whether the target population grows successfully. Changes in one condition can alter the effects of the others, so the formulation must match the biological requirements of the selected microorganism or cell type. Careful adjustment improves reproducibility and helps prevent competing populations from dominating the culture.
A suitable formulation gives the desired population conditions that support its growth while limiting the relative success of competing organisms or unwanted cells. As the target population grows under those favorable conditions, it becomes easier to detect, isolate, and study from a mixed sample. This enrichment is particularly useful when the organism of interest is initially present at low abundance.
Preparation begins with accurate measurement of the formulation’s components, followed by dissolving them and adjusting the pH. The completed medium is then sterilized and handled aseptically to preserve its intended composition and prevent contamination. Each step contributes to consistent growth conditions, allowing differences in culture results to reflect biological behavior rather than variation in preparation.
Sterilization helps remove unwanted biological contaminants from the prepared medium, while aseptic handling reduces the chance that contamination will be introduced afterward. These controls are complementary rather than interchangeable. Without them, competing organisms or unwanted cells could grow alongside the target population, making isolation, identification, and interpretation of physiological or metabolic studies less reliable.
Researchers may choose this approach when they need to isolate or identify a desired organism from a mixed sample, especially when the target population is present at low abundance. The same strategy supports investigations of microbial physiology and metabolism. It also contributes to diagnostic and environmental analyses by improving recovery of organisms that might otherwise be difficult to detect.
Reproducibility depends on controlling the medium’s composition and preparation conditions, including measurement, dissolution, pH adjustment, sterilization, and aseptic handling. Consistent control of nutrients, osmotic conditions, oxygen availability, and inhibitory components helps produce comparable growth environments across experiments. This consistency strengthens interpretation of isolation results and studies of microbial physiology or metabolism.