• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.64-69
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• 1991

- The effects of sodium acetate on the production of $\gamma$-linolenic acid (GLA) and the secretion of the mycelial lipid into the culture medium with noninnic surfactants were studied with Mucor sp. KCTC 8405P. In the addition of 2.0%) sodium acetate to the basal medium, dry cell weight and total lipid content were increased from 7.8 g/l and 2.46 g/l to 16.0 g/1 and 4.77 g/l, but GLA content was decreased from 18.6% to 13.85%. The growth of Mucor sp. KCTC 8405P was greatly dependent on both the initial pH and the concentration of sodium acetate of culture medium, which was considered as the results of the formation of acetic acid because the fungal growth was completely inhibited at the concentration of acetic acid higher than 22 mM. With the decrease of the oxygen supply, the cell growth, total lipid, and GLA content were sharply decreased in the presence of 2.0% sodium acetate. For the secretion of mycelial lipid into the culture medium, the effects of the various nonionic surfactants were examined. In the addition of 0.5% Tween 80 or Span 80 to the basal medium, 194 mg/l or 263 mg/l of GLA was obtained in the culture medium.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.119.1-119
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• 2003

The glyoxysomal nature of microbodies was determined in Botryosphaeria dothidea hyphae based on morphology and in situ enzyme characteristics by transmission electron microscopy and cytochemistry. Bound by a single membrane, microbodies had a homogeneous matrix and varied in size ranging from 200 to 400 m in diameter. Microbodies had crystalline inclusion(s) which consisted of parallel arrays of fine tubules in their matrices. Microbodies and lipid globules were frequently placed in close association with each other, forming microbody-lipid globule complexes in hyphae. The cytochemical activities of catalase and malate synthase were localized in matrices of microbodies, showing intense electron-density of the organelle. In addition, the immunogold labeling detected the presence of catalase in multivesicular bodies and hyphal cell walls as well as in matrices and crystalline inclusions of microbodies, supporting the enzyme secretion through cell walls. Meanwhile, isocitrate Iyase was localized only in matrices of microbodies. These results suggest that microbodies, particularly complexed with lipid globules, in the fungal hyphae are functionally defined as glyoxysomes, where glyoxysomal enzymes are biochemically active for the glyoxylate cycle to be a metabolic pathway in gluconeogenesis. (Mycology and Fugus Diseases)