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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Korean Journal of Microbiology
Journal Basic Information
Journal DOI :
The Microbiological Society of Korea
Editor in Chief :
Volume & Issues
Volume 6, Issue 4 - Dec 1968
Volume 6, Issue 3 - Sep 1968
Volume 6, Issue 2 - Jun 1968
Volume 6, Issue 1 - Mar 1968
Selecting the target year
Studies on the cellular metabolism in microorganisms as influenced by gamma-irradiation.(IV) "on the carbohydrate metabolism of yeast irradiated by
The Korean Journal of Microbiology, volume 6, issue 2, 1968, Pages 41~53
Studies on the carbohydrate metabolism of yeast as influenced by gamma-irradiation from cobalt-60 have been carried, then the mechanisms of radiation effect on respiration and fermentation were discussed under considerations of permeable changes of irradiated cell membrane. The cells of baker's yeast (Saccharomyces cerevisiae) which had been gamma-irradiated of 240 k.r. doses for an hour, then were put into aerobic oxidation and anaerobic fermentation without substrate. Total and fractionated carbohydrates of irradiated yeast cells were determined by calorimetric method with anthrone and orcinol reagents, the amounts of total carbohydrate, trehalose, RNA-ribose, PCA-soluble glycogen, alkali-soluble glycogen, acetic acid-soluble glycogen, mannan and glucan were determined according to the course of aerobic oxidation and anaerobic fermentation. It is found that the carbohydrates of irradiated cells leak out and amount of the losses teaches eleven times more than that of control, the volume of losses are seems to be replaced by water, it can be suggested the damage of gamma-irradiation occurs in the site of passive transport of cell membrane. The endogeneous aerobic respiration of irradiated cells are increased much more than control, the synthesis of reserve glycogen, glucan and RNA-ribose promoted much more than control. The anaerobic fermentation of irradiated cells are also increased than that of control, but the breakdown of carbohydrate is less than endogeneous respiration of irradiated cells. The synthetic rate is also less than that of aerobic oxidation. In irradiated yeast cells, trehalose is revealed to be primary substrate for endogeneous carbohydrate metabolism, so it is proved that the enzymic patterns are not changed but the activities of enzymes relating endogeneous respiration and autofermentation is activated. It is to be considerable to distiguish endogeneous respiration and autofermentation from exogeneous respiration and fermentation on irradiation, for membrane permeability changes and loses out carbohydrate by ionizing radiation.
Studies on the cellular metabolism in microorganisms as influenced by gamma-irradiation.(V) "On the membrane permeability changes and leakage of celluar constituents of irradiated yeast cell"
The Korean Journal of Microbiology, volume 6, issue 2, 1968, Pages 54~62
The effect of gamma-ray on yeast cells Sacch. cerevisiae, and the leakage of cellular constituents such as carbohydrates, ribose, amino acids, inorganic phosphates and organic phosphates have been studied. The samples of yeast cells washed throughly and starved intensively, radiation effects were compared with those of control (un-starved), the irradiation dose rates are in the range from 24 Kr. up. to 480, Kr. The loss of 260m
. absorbing material, are also observed. Mechanisms of membrane damage by gamma-irradiation are discussed corelating to permeability changes and loss of substances, then active and passive transport process are also under considerations in discussion. The experimental results are as follows, 1. Carbohydrates of yeast cell leak out by gamma-irradiation, and amounts of loss increase proportionally as the increasing of radiation dose, curve of carbohydrates loss in starved cells is parallel with those of non-starved cells. 2. Ribose leak out less than that of carbohydrate from irradiated cell, the dose response curve of loss is straight and proportional to the increasing of radiation doses, slope of the curve is much lower than of carbohydrates. 3. Amino acids also leak out and the curve of losses to radiation is not proportional, it is revealed that there are little losses from yeast at lower doses of irradiation. 4. The losses of inorganic phosphates increase unproportionally to the increasing of irradiation doses, there are little leakage at the lower doses of irradiation. The losses of organic phosphates increase proportionally to the increasing of irradiation doses, and the amount of losses are much more than that of inorganic phosphate at lower doses of irradiation. 5. Leakage from irradiated yeast cells was shown to be due to passive transport process not an energy requiring process of ion transport. 6. Loss of 260 m
. absorbing material is little more than that of control yeast by the gamma-irradiation dose of 120K.r. and 240K.r.
Studies on analysis of the Korean lager beers. (I) "On the estimation of total carbohydrates, amino acids and peptides"
The Korean Journal of Microbiology, volume 6, issue 2, 1968, Pages 63~67
Total carbohydrates, amino acids and peptide-like substances in two kinds of Korean lager beers have been analyzed by the calorimetric method of Dreywood's anthrone reagent and Fowden's ninhydrin reagent. The samples were fractionated with column of ion-exchange resin. The experimental results are as follows; 1. Amounts of non-hydrolyzed carbohydrates in the part of column processed is 1. 82% and 1. 96 % (the value was measured by Bertrand's method). But the amounts of those measured by Dreywood's anthrone method are 5.57% and 4.25%, this values are much more than those of Bertrand's method. 2. It can be estimated the amounts of gum and dextrin are 3.75% and 3.30% in both two beers, by comparison of samples with the above mentioned two method. 3. The amounts of carbohydrates by anthrone reagent in acid-hydrolyzed beers are much increased than those of non-hydrolyzed, so it is suggested the presence of polymer carbohydrates which couldn't be detected by Bertrand's method. 4. Total amounts of amino acids are 0.015% and 0.025% (as glycine) in non-hydrolyzed beers measured by ninhydrine color reaction method, on the other hand the amount of amino acids in acid hydrolyzed beers are 0.06% and 0.056%, this is much more than those of nonhydrolysis. The different amounts means that of peptide-like substances. 5. It is necessary to determine the constituent of amino acid for the better taste of beer, and also it is desirable to check the role of carbohydrates in the course of fermentation, mashing and on lager beer for effective utilization of carbohydrate materials to eliminate the losses.
Effects of gibberellin on alpha-and beta-amylase activities of Aspergillus oryzae
The Korean Journal of Microbiology, volume 6, issue 2, 1968, Pages 68~74
Effects of gibberellin on alpha and beta-amylase activities of Aspergillus orygae var. microsporus have been studied. Results obtained are as follows: 1. The growth of mycelium and dry weight of surface ped was accelerated by 0, 0001% gibberellin solution, spores of Aspergillus oryzae var. microsporus. were preveously soaked for three days. 2. Adding to culture media with 0, 0015% gibberellin, alpha-amylase was increased 50% much as beta-Amylase was as much as 50%.