CHU 13 medium is a culture medium used in microbiology for the growth of certain algal species, first published by S.P. Chu in 1942.S.P. Chu (Aug., 1942) The Journal of Ecology, Vol. 30, No. 2, pp. 284-325. https://www.cpp.edu/~biodiesel/documents/reference/Chu42AlgaIsolGrowth.pdf It is used as growth medium for the biofuel candidate alga Botryococcus braunii.C. Largeau, E. Casadevall, C. Berkaloff and P. Dhamelincout (1980) Phytochemistry, 19, 1943.
CHU 13 includes essential minerals and trace elements that are required by algae for growth, but does not include a carbon source and so is only appropriate for growth of phototrophs. It can be prepared as either a liquid medium or as an agar medium.
+ Modified CHU13 Medium Compound mg/LKNO3 400K2HPO4 80CaCl2 dihydrate 107MgSO4 heptahydrate 200Ferric citrate 20Citric acid 100CoCl2 0.02H3BO3 5.72MnCl2 tetrahydrate 3.62ZnSO4 heptahydrate 0.44CuSO4 pentahydrate 0.16Na2MoO4 0.0840.072 N H2SO4 1 drop
The remaining volume is pure, de-ionized water.
Because it is difficult to weigh out some of the trace minerals, it is advisable to create a mixture of all components at a large concentration, such as a thousand times these measures, and then mix with the appropriate amount of (pure, de-ionized) water. Correct pH to 7.5, and then autoclave.
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