Agar-based culture medium

In the larval feeding method, formaldehyde is added to the agar-based culture medium on which the larvae develop. My original observation identifying the basis for its mode of action was that formaldehyde exhibits a mutagenic effect only when a source of (yeast) RNA is present in the culture medium [2]. Further analysis showed that the requirement for RNA was due solely to a need for its adenylic acid component. 

CULTURE MEDIUM GC AGAR BASE DEHYDRATED 0.25 POUNDS 6550009355870 BT 21.41 ... 

The method is based on the perturbation of the respiratory activity of yeast, Saccharomyces cerevisiae, immobilized on an agar gel containing the culture medium (i.e., agarized medium ), by the toxic test substance. Glucose is used as substrate while the substances tested consist of several metallic ions, phenols and cationic or anionic surfactants, pesticides and other toxics. 

Callus cultures, initiated from leaves or stems of growing plants are grown on an agar based medium in the presence of growth factors (cytokinins and auxins, e.g. 2,4D or IAA). Undifferentiated cells can also be grown in suspension in similar media (without agar), but to initiate differentiation the concentration of auxin must be lowered. The optimum concentration of hormones must be determined by experimentation for each cell type. More details are to be found in Dixon (1985). 

The colony characteristics and microscopic morphology used for the identification of dematiaceous fungi are based upon cultures that are approximately 2 weeks old and have been grown at 25 to 30°C on a medium such as potato dextrose agar or cornmeal agar. These media... 

The multicellular spheroids were initiated by the agar overlay method described by Yuhas. After 6 days in culture, spheroids with diameters between 200 pm and 300 pm were selected for growth experiments and transferred to 16mm multiwell culture dishes. The diameters of the spheroids were determined by using an inverted microscope with a calibrated graticule in the eyepiece. The wells were base-coated with 0.5ml 0.75% DMEM-agar and filled with 1 ml of medium. 

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