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Biomedical subjects

F Yoshida

Publications and source records attributed to F Yoshida.

At least 145 records · Page 8Linked to original sources
PubMed1969

Production of thermostable alkaline proteases by thermophilic Streptomyces.

Conditions for the production of thermostable proteases (alkaline proteinase and carboxypeptidase) by a thermophilic streptomycete (Streptomyces rectus var. proteolyticus) were investigated in 20-liter volumes. Proteinase production was affected by the concentration of defatted soybean powder, its optimum being 1.2% in medium containing 2.0% soluble starch. Relatively high concentration of phosphate (0.3 to 0.4% K(2)HPO(4)) was needed for the maximum enzyme production. A large inoculum size (5 to 10%) was favorable, but the inoculum age did not significantly influence the production. The yield increase of 20 to 30% was obtained by feeding of medium during fermentation. The optimal temperature for proteinase production was 50 C, at which the maximal rate of production was 66.2 proteinase units per ml per hr, whereas at 40 C it was 9.0. Production at 50 C reached the maximum within 12 to 16 hr. The optimal agitation rate was different for the production of proteinase and carboxypeptidase, 400 rev/min for the former and 500 rev/min for the latter. The optimal aeration for proteinase production was 20 to 30 liters/min at 400 rev/min, whereas carboxypeptidase production was not markedly affected by aeration rate. The possibility that carboxypeptidase production was correlated with the shear of mycelium was discussed.

Bacteriological Techniques↗
PubMed1968

Effect of lipid materials on the production of lipase by Torulopsis ernobii.

The yeast Torulopsis ernobii produced approximately 50 units of extracellular lipase (glycerol ester hydrolase, E.C. 3.1.1.3) per ml when grown in 30-liter fermentors at 33 C for 40 hr in a base medium at pH 5.0. The addition of fats, oils, triglycerides, or higher fatty acids to this medium at concentrations of 0.2 to 0.6% markedly increased production; twofold increases in yield were obtained when 0.2% olive oil or a mixture of 0.14% oleic acid and 0.04% palmitic acid was added. The production of lipase paralleled growth, and the role of lipid materials in augmenting lipase production appears to be related to cell growth.

Cryptococcus↗