• Journal of Korean Society of Environmental Engineers
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• v.39 no.11
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• pp.599-606
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• 2017

The effects of microbubble-oxygen physicochemical method for the removal of organic pollutants, nitrogen, and phosphorus contained in animal manure were investigated using a laboratory scale single reactor. The characteristics of used livestock manure were $36,894{\pm}5,024mg\;TCOD/L$, $22,031{\pm}2,018mg\;SCOD/L$, $4,150{\pm}35mg\;NH_4-N/L$, and $659{\pm}113mg\;PO_4-P/L$. It was confirmed that the amount of organic pollutants, nitrogen, and phosphorus removal was increased by the use of oxygen rather than air as the gas supplied with the microbubble, and by input of larger oxygen amount. When the oxygen was fed with 600 mL flow rate per minute, TCOD and phosphorus removal were 2.5 times and 5.6 times higher than those of air supplied. As the microbubble-oxygen reaction time was longer, the removal rate of nutrients increased gradually. The removal rates of ammonium and phosphorus reach to $41.03{\pm}0.20%$ and $65.49{\pm}1.39%$, respectively, after 24 hours. When the coagulation treatment method was applied to increase phosphorus removal rate from the effluent of microbubble-oxygen treatment, the phosphorus was removed up to 92.7%. However, the removal rate of organic pollutants (TCOD) was as small as $28.7{\pm}0.2%$ within the first 6 hours, and then the negligible removal of TCOD was recorded. This study suggests that microbubble-oxygen can be applied not only livestock manure but also aeration tank of various wastewater treatment plant, which can reduce the load on the associated unit process and produce stable high-quality effluent.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.944-955
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• 2000

Background : In patients with chronic obstructive pulmonary disease(COPD), several factors have been associated with a poor prognosis. These include old age, low $FEV_1$ low diffusing capacity, high alveolar-arterial oxygen pressure difference, and finally cor pulmonale. This study was done to investigate if the ECG signs suggesting cor pulmonale were independent prognostic factors in patients with COPD. Method : We analyzed ECG, pulmonary function data and arterial blood gas values in 61 patients who were admitted through the emergency department with an acute exacerbation of COPD. The ECG signs reflecting cor pulmonale were right strial overloading(RAO), right bundle branch block, right ventricular hypertrophy and low-voltage QRS. The 61 patients were divided into 2 groups ; group I with no ECG signs(n=36) and group II with one or more ECG signs(n=25) suggesting cor, pulmonale. Results : Poor, prognostic factors by univariate analysis were low $FEV_1$, $FEV_1$ % pred., VC % pred., DLco, DLco % pred., $PaO_2$ and $SaO_2$ high $PaCO_2$ presence of ECG signs reflecting cor pulmonale, presence of mental status change, use of mechanical ventilator, and long term use of glucocorticoid. A multivariate analysis indicated that age(risk ratio=1.13, 95% confidence interval 1.05-1.23), DLco % pred. (risk ratio=0,97. 95% confidence interval 0.94-0.99), $PaO_2$ (risk ratio=0.95, 95% confidence interval 0.90-0.99) and RAO(risk ratio=5.27, 95% confidence interval 1.40-19.85) were independent prognostic factors of survival. There was a significant difference in survival between the patients with and without RAO(p=0.038). The survival rates at 1, 2, and 5 years were 94.5%. 81.4%, and 50.0% in patients without RAO and 82.4%, 70.6%, and 27.5% in patients with RAO, respectively. Conclusion : These results suggest that the presence of ECG signs reflecting cor pulmonale is a predictor of survival and that RAO of these ECG signs is a significant independent predictor of survival in patients with COPD.

• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.568-578
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• 2001

Background : Lung cancer is frequently cited as an example of a disease caused solely by exposure to environmental carcinogens. However, there is a growing realization that the genetic constitution is also important in determining individual's susceptibility to lung cancer. This genetic susceptibility may result from functional polymorphims of the genes involved in carcinogen metabolism. In this study, the association between GSTM1 and CYP1A1 polymorphisms and the lung cancer risk in Korean males was investigated. Materials and Method : The study population consisted of 153 male lung cancer patients and 143 healthy male controls. The GSTM1 and CYP1A1 genotypes were determined by multiplex PCR and PCR-RFLP analysis. Result : There were no significant differences in the frequency of the GSTM1 null genotype between the cases and the controls. When the cases were categorized by their histologic type, the frequency of the GSTM1 null genotype in the small cell carcinoma group was higher than those of the controls(67.2% vs 55.9%), but the difference was not statistically significant(OR=1.772 ; 95% CI=0.723-4.340). The distribution of the CYP1A1 MspI genotypes among the cases were similar to those among the controls. When the cases were grouped by their histologic type, the ml/m1, ml/m2, m2/m2 genotypes frequencies among the small cell carcinomas(23.0%, 38.5%, and 38.5%, respectively) were significantly different from those of the controls(36.4%, 46.2%, and 7.4%, respectively, p<0.05). When the m1/m1 genotype was used as a reference, the ml/m2 and m2/m2 genotypes were associated with an increased risk for small cell lung cancer(ml/m2 genotype : OR=1.337, 95% CI=0.453-3.947 ; m2/m2 genotype : OR=3.374, 95% CI=1.092-10.421). Conclusion : These results suggest that the GSTM1 and CYP1A1 genotypes may be a genetic determinant of the risk for lung cancer, particlulary small cell carcinoma. Further investigation is needed to confirm these results.

• The Korean Journal of Mycology
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• v.10 no.1
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• pp.33-39
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• 1982

Carpophores of ten Korean strains of Lentinus edodes (Berk.) Singer, an antitumor polysaccharide producing fungus, were extracted with 0.1N NaOH solution. The extracts were dialized for seven days in distilled water and lyophilized to produce crude polysaccharide powders. Thus obtained crude polysaccharide samples were assayed for sugar contents by colorimetric method with anthrone reagent. Among ten strains examined Lentinus edododes-DMC7 was found to be the richest strain in polysaccharide content of carpophores. By shake culture experiment for biomass production, L. edodes-DMC7 was found to be the second most productive strain among seven strains examined. Cultural characteristics of L. edodes-DMC7 were investigated by shake culture method. The best result was obtained when L. edodes-DMC7 was cultured in the medium containing glucose 8g, starch 80g, yeast extract 12g, $KH_2PO_4\;0.87g,\;MgSO_4{\cdot}7H_2O\;O.5g,\;CaCl_2\;0.3g,\;FeSO_4{\cdot}7H_2O\;10mg\;ZnSO_4{\cdot}7H_2O\;4mg,\;CuSO_4{\cdot}5H_2O\;lmg,\;MnCl_2{\cdot}4H_2O\;7mg\;per\;11\;at\;28^{\circ}C$, 180 rpm, for 12 days. Thus thirty-three grams of dry mycelia was obtained per one liter of medium.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.409-415
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• 1999

To evaluate the purification capacity of pollutants (COD, $PO_4^{3-}-p$, $NO_3^{-}-N$, Cu, Cd, Pb) in the three tidal flats, Eueunri, Gyewhado, Chunjangdae, the experiments were carried out with the batch reactor equipped with artifical tidal flats. Eueunri tidal flat was $98.8\%$ content of silt and clay and Chungjangdae was $97.84\%$ content of sand. The organic matters (I.L., $COD_{sed}$, POC) in Eueunri tidal flat were 2$\~$8 times higher than other tidal flats. The purification capacity of COD was 0.75 kg/ha/12 hr in Eueunri, 0.60 kg/ha/12 hr in Gyewhado and 0.55 kg/ha/12 hr in Chunjangdae. The mean purification capacity of COD in three tidal flats was 1.27 kg/ha/day. The calculated purification capacity of COD was 25.4 ton/day in the disappeared tidal flat areas (20,000 ha) of the Saemangeum reclamation. The purification capacity of phosphorus was 0.21 kg/ha/12 hr in Gyewhado, 0.39 kg/ha/12 hr in Eueunri and 0.22 kg/ha/12hr in Chunjangdae. The nitrate was 0.53, 0.74 and 0.43kg/ha/12hr, respectively. The purification capacity of heavy metals (Cu, Cd, Pb) were 88.9g/ha/12hr, 11.0g/ha/12hr, 1.7g/ha/12hr in Gyewhado, 89.1g/ha/12hr, 18.0g/ha/12hr, 2.6g/ha/12hr in Eueunri and 55.3g/ha/12hr, 18.0g/ha/12hr, 2.1g/ha/12hr in Chunjangdae, respectively. Accordingly, the purification capacity of pollutants in Eueunri tidal flat with high contents of organic matter were higher than other tidal flats. So, the purification capacity of pollutants were affected by physical and/or chemical characteristics of tidal flats.

• Korean Journal of Environmental Agriculture
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• v.42 no.1
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• pp.52-62
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• 2023

This study focused on determining the specific causes and prevention methods of mass fish deaths occurred in five reservoirs (Gagugi, Neupgokgi, Danggokgi, Sagokji, and Hangokji) in Andong-si. For this purpose, a survey of agricultural land and livestock in the upper part of the reservoirs and analysis of water quality in the reservoir irrespective of whether it rains or not were conducted. We attempted to examine the changes in dissolved oxygen (DO) in the surface and bottom layers of reservoirs and changes in DO depending on the amount of livestock compost and time. Based on the above investigations, treatment plans were established to efficiently control the inflow of contaminated water into reservoirs. The rainfall and farmland areas in the upper part of the reservoir were investigated using Google and aviation data provided by the Ministry of Land, Infrastructure, and Transport. The current status of livestock farms distributed around the reservoirs was also examined because compost from these farms can flow into the reservoir when it rains. Various water quality parameters, such as phosphate phosphorus (PO₄-P) and ammonium nitrogen (NH₃-N), were analyzed and compared for each reservoir during the rainy season. Changes in the DO concentration and electrical conductivity (EC) were also observed at the inlet of the reservoir during raining using an automated instrument. In addition, DO was measured until the concentration reached 0 ppm in 10 min by adding livestock compost at various concentrations (0.05%, 0.1%, 0.3%, and 0.5% by wt.), where the concentration of the livestock compost represents the relative weight of rainwater. The DO concentration in the surface layer of reservoirs was 3.7 to 5.3 ppm, which is sufficient for fish survival. However, the fish could not survive at the bottom layer with DO concentration of 0.0-2.1 ppm. When the livestock compost was 0.3%, DO required 10-19 h to reach 0 ppm. Considering these results, it was confirmed that the DO in the bottom layer of the reservoir could easily change to an anaerobic state within 24 h when the livestock compost in the rainwater exceeds 0.3%. The results show that the direct cause of fish mortality is the inflow of excessive livestock compost into reservoirs during the first rainfall in spring. All the surveyed reservoirs had relatively good topographical features for the inflow of compost generated from livestock farms. This keeps the bottom layer of the reservoir free of oxygen. Therefore, to prevent fish death due to insufficient DO in the reservoir, measures should be undertaken to limit the amount of livestock compost flowing into the reservoir within 0.3%, which has been experimentally determined. As a basic countermeasure, minerals such as limestone, dolomite, and magnesia containing calcium and magnesium should be added to the compost of livestock farms around the reservoir. These minerals have excellent pollutant removal capabilities when sprayed onto the compost. In addition, measures should be taken to prevent fish death according to the characteristics of each reservoir.

• Journal of Global Scholars of Marketing Science
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• v.19 no.3
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• pp.17-27
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• 2009

Price promotion typically reduces the price for a given quantity or increases the quantity available at the same price, thereby enhancing value and creating an economic incentive to purchase. It often is used to encourage product or service trial among nonusers of products or services. Thus, it is important to understand the effects of price promotions on quality perception made by consumer who do not have prior experience with the promoted brand. However, if consumers associate a price promotion itself with inferior brand quality, the promotion may not achieve the sales increase the economic incentives otherwise might have produced. More specifically, low qualitative perception through price promotion will undercut the economic and psychological incentives and reduce the likelihood of purchase. Thus, it is important for marketers to understand how price promotional informations about a brand have impact on consumer's unfavorable quality perception of the brand. Previous literatures on the effects of price promotions on quality perception reveal inconsistent explanations. Some focused on the unfavorable effect of price promotion on consumer's perception. But others showed that price promotions didn't raise unfavorable perception on the brand. Prior researches found these inconsistent results related to the timing of the price promotion's exposure and quality evaluation relative to trial. And, whether the consumer has been experienced with the product promotions in the past or not may moderate the effects. A few studies considered differences among product categories as fundamental factors. The purpose of this research is to investigate the effect of price promotional informations on consumer's unfavorable quality perception under the different conditions. The author controlled the timing of the promotional exposure and varied past promotional patterns and information presenting patterns. Unlike previous researches, the author examined the effects of price promotions setting limit to pretrial situation by controlling potentially moderating effects of prior personal experience with the brand. This manipulations enable to resolve possible controversies in relation to this issue. And this manipulation is meaningful for the work sector. Price promotion is not only used to target existing consumers but also to encourage product or service trial among nonusers of products or services. Thus, it is important for marketers to understand how price promotional informations about a brand have impact on consumer's unfavorable quality perception of the brand. If consumers associate a price promotion itself with inferior quality about unused brand, the promotion may not achieve the sales increase the economic incentives otherwise might have produced. In addition, if the price promotion ends, the consumer that have purchased that certain brand will likely to display sharply decreased repurchasing behavior. Through a literature review, hypothesis 1 was set as follows to investigate the adjustive effect of past price promotion on quality perception made by consumers; The influence that price promotion of unused brand have on quality perception made by consumers will be adjusted by past price promotion activity of the brand. In other words, a price promotion of an unused brand that have not done a price promotion in the past will have a unfavorable effect on quality perception made by consumer. Hypothesis 2-1 was set as follows : When an unused brand undertakes price promotion for the first time, the information presenting pattern of price promotion will have an effect on the consumer's attribution for the cause of the price promotion. Hypothesis 2-2 was set as follows : The more consumer dispositionally attribute the cause of price promotion, the more unfavorable the quality perception made by consumer will be. Through test 1, the subjects were given a brief explanation of the product and the brand before they were provided with a $2{\times}2$ factorial design that has 4 patterns of price promotion (presence or absence of past price promotion * presence or absence of current price promotion) and the explanation describing the price promotion pattern of each cell. Then the perceived quality of imaginary brand WAVEX was evaluated in the scale of 7. The reason tennis racket was chosen is because the selected product group must have had almost no past price promotions to eliminate the influence of average frequency of promotion on the value of price promotional information as Raghubir and Corfman (1999) pointed out. Test 2 was also carried out on students of the same management faculty of test 1 with tennis racket as the product group. As with test 1, subjects with average familiarity for the product group and low familiarity for the brand was selected. Each subjects were assigned to one of the two cells representing two different information presenting patterns of price promotion of WAVEX (case where the reason behind price promotion was provided/case where the reason behind price promotion was not provided). Subjects looked at each promotional information before evaluating the perceived quality of the brand WAVEX in the scale of 7. The effect of price promotion for unfamiliar pretrial brand on consumer's perceived quality was proved to be moderated with the presence or absence of past price promotion. The consistency with past promotional behavior is important variable that makes unfavorable effect on brand evaluations get worse. If the price promotion for the brand has never been carried out before, price promotion activity may have more unfavorable effects on consumer's quality perception. Second, when the price promotion of unfamiliar pretrial brand was executed for the first time, presenting method of informations has impact on consumer's attribution for the cause of firm's promotion. And the unfavorable effect of quality perception is higher when the consumer does dispositional attribution comparing with situational attribution. Unlike the previous studies where the main focus was the absence or presence of favorable or unfavorable motivation from situational/dispositional attribution, the focus of this study was exaus ing the fact that a situational attribution can be inferred even if the consumer employs a dispositional attribution on the price promotional behavior, if the company provides a persuasive reason. Such approach, in academic perspectih sis a large significance in that it explained the anchoring and adjng ch approcedures by applying it to a non-mathematical problem unlike the previous studies where it wis ionaly explained by applying it to a mathematical problem. In other wordn, there is a highrspedency tmatispositionally attribute other's behaviors according to the fuedach aal attribution errors and when this is applied to the situation of price promotions, we can infer that consumers are likely tmatispositionally attribute the company's price promotion behaviors. Ha ever, even ueder these circumstances, the company can adjng the consumer's anchoring tmareduce the po wibiliute thdispositional attribution. Furthermore, unlike majority of previous researches on short/long-term effects of price promotion that only considered the effect of price promotions on consumer's purchasing behaviors, this research measured the effect on perceived quality, one of man elements that affects the purchasing behavior of consumers. These results carry useful implications for the work sector. A guideline of effectively providing promotional informations for a new brand can be suggested through the outcomes of this research. If the brand is to avoid false implications such as inferior quality while implementing a price promotion strategy, it must provide a clear and acceptable reasons behind the promotion. Especially it is more important for the company with no past price promotion to provide a clear reason. An inconsistent behavior can be the cause of consumer's distrust and anxiety. This is also one of the most important factor of risk of endless price wars. Price promotions without prior notice can buy doubt from consumers not market share.

• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.1
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• pp.3225-3262
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• 1974

The purposes of this thesis are to clarify experimentally the variation of ground water temperature in tube wells during the irrigation period of paddy rice, and the effect of ground water irrigation on the growth, grain yield and yield components of the rice plant, and, furthermore, when and why the plant is most liable to be damaged by ground water, and also to find out the effective ground water irrigation methods. The results obtained in this experiment are as follows; 1. The temperature of ground water in tube wells varies according to the location, year, and the depth of the well. The average temperatures of ground water in a tubewells, 6.3m, 8.0m deep are $14.5^{\circ}C$ and $13.1^{\circ}C$, respercively, during the irrigation period of paddy rice (From the middle of June to the end of September). In the former the temperature rises continuously from $12.3^{\circ}C$ to 16.4$^{\circ}C$ and in the latter from $12.4^{\circ}C$ to $13.8^{\circ}C$ during the same period. These temperatures are approximately the same value as the estimated temperatures. The temperature difference between the ground water and the surface water is approximately $11^{\circ}C$. 2. The results obtained from the analysis of the water quality of the "Seoho" reservoir and that of water from the tube well show that the pH values of the ground water and the surface water are 6.35 and 6.00, respectively, and inorganic components such as N, PO4, Na, Cl, SiO2 and Ca are contained more in the ground water than in the surface water while K, SO4, Fe and Mg are contained less in the ground water. 3. The response of growth, yield and yield components of paddy rice to ground water irrigation are as follows; (l) Using ground water irrigation during the watered rice nursery period(seeding date: 30 April, 1970), the chracteristics of a young rice plant, such as plant height, number of leaves, and number of tillers are inferior to those of young rice plants irrigated with surface water during the same period. (2) In cases where ground water and surface water are supplied separately by the gravity flow method, it is found that ground water irrigation to the rice plant delays the stage at which there is a maximum increase in the number of tillers by 6 days. (3) At the tillering stage of rice plant just after transplanting, the effect of ground water irrigation on the increase in the number of tillers is better, compared with the method of supplying surface water throughout the whole irrigation period. Conversely, the number of tillers is decreased by ground water irrigation at the reproductive stage. Plant height is extremely restrained by ground water irrigation. (4) Heading date is clearly delayed by the ground water irrigation when it is practised during the growth stages or at the reproductive stage only. (5) The heading date of rice plants is slightly delayed by irrigation with the gravity flow method as compared with the standing water method. (6) The response of yield and of yield components of rice to ground water irrigation are as follows: \circled1 When ground water irrigation is practised during the growth stages and the reproductive stage, the culm length of the rice plant is reduced by 11 percent and 8 percent, respectively, when compared with the surface water irrigation used throughout all the growth stages. \circled2 Panicle length is found to be the longest on the test plot in which ground water irrigation is practised at the tillering stage. A similar tendency as that seen in the culm length is observed on other test plots. \circled3 The number of panicles is found to be the least on the plot in which ground water irrigation is practised by the gravity flow method throughout all the growth stages of the rice plant. No significant difference is found between the other plots. \circled4 The number of spikelets per panicle at the various stages of rice growth at which_ surface or ground water is supplied by gravity flow method are as follows; surface water at all growth stages‥‥‥‥‥ 98.5. Ground water at all growth stages‥‥‥‥‥‥62.2 Ground water at the tillering stage‥‥‥‥‥ 82.6. Ground water at the reproductive stage ‥‥‥‥‥ 74.1. \circled5 Ripening percentage is about 70 percent on the test plot in which ground water irrigation is practised during all the growth stages and at the tillering stage only. However, when ground water irrigation is practised, at the reproductive stage, the ripening percentage is reduced to 50 percent. This means that 20 percent reduction in the ripening percentage by using ground water irrigation at the reproductive stage. \circled6 The weight of 1,000 kernels is found to show a similar tendency as in the case of ripening percentage i. e. the ground water irrigation during all the growth stages and at the reproductive stage results in a decreased weight of the 1,000 kernels. \circled7 The yield of brown rice from the various treatments are as follows; Gravity flow; Surface water at all growth stages‥‥‥‥‥‥514kg/10a. Ground water at all growth stages‥‥‥‥‥‥428kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥430kg/10a. Standing water; Surface water at all growh stages‥‥‥‥‥‥556kg/10a. Ground water at all growth stages‥‥‥‥‥‥441kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥450kg/10a. The above figures show that ground water irrigation by the gravity flow and by the standing water method during all the growth stages resulted in an 18 percent and a 21 percent decrease in the yield of brown rice, respectively, when compared with surface water irrigation. Also ground water irrigation by gravity flow and by standing water resulted in respective decreases in yield of 16 percent and 19 percent, compared with the surface irrigation method. 4. Results obtained from the experiments on the improvement of ground water irrigation efficiency to paddy rice are as follows; (1) When the standing water irrigation with surface water is practised, the daily average water temperature in a paddy field is 25.2$^{\circ}C$, but, when the gravity flow method is practised with the same irrigation water, the daily average water temperature is 24.5$^{\circ}C$. This means that the former is 0.7$^{\circ}C$ higher than the latter. On the other hand, when ground water is used, the daily water temperatures in a paddy field are respectively 21.$0^{\circ}C$ and 19.3$^{\circ}C$ by practising standing water and the gravity flow method. It can be seen that the former is approximately 1.$0^{\circ}C$ higher than the latter. (2) When the non-water-logged cultivation is practised, the yield of brown rice is 516.3kg/10a, while the yield of brown rice from ground water irrigation plot throughout the whole irrigation period and surface water irrigation plot are 446.3kg/10a and 556.4kg/10a, respectivelely. This means that there is no significant difference in yields between surface water irrigation practice and non-water-logged cultivation, and also means that non-water-logged cultivation results in a 12.6 percent increase in yield compared with the yield from the ground water irrigation plot. (3) The black and white coloring on the inside surface of the water warming ponds has no substantial effect on the temperature of the water. The average daily water temperatures of the various water warming ponds, having different depths, are expressed as Y=aX+b, while the daily average water temperatures at various depths in a water warming pond are expressed as Y=a(b)x (where Y: the daily average water temperature, a,b: constants depending on the type of water warming pond, X; water depth). As the depth of water warning pond is increased, the diurnal difference of the highest and the lowest water temperature is decreased, and also, the time at which the highest water temperature occurs, is delayed. (4) The degree of warming by using a polyethylene tube, 100m in length and 10cm in diameter, is 4~9$^{\circ}C$. Heat exchange rate of a polyethylene tube is 1.5 times higher than that or a water warming channel. The following equation expresses the water warming mechanism of a polyethylene tube where distance from the tube inlet, time in day and several climatic factors are given: {{{{ theta omega (dwt)= { a}_{0 } (1-e- { x} over { PHI v })+ { 2} atop { SUM from { { n}=1} { { a}_{n } } over { SQRT { 1+ {( n omega PHI) }^{2 } } } } LEFT { sin(n omega t+ { b}_{n }+ { tan}^{-1 }n omega PHI )-e- { x} over { PHI v }sin(n omega LEFT ( t- { x} over {v } RIGHT ) + { b}_{n }+ { tan}^{-1 }n omega PHI ) RIGHT } +e- { x} over { PHI v } theta i}}}}{{{{ { theta }_{$\infty$ }(t)= { { alpha theta }_{a }+ { theta }_{ w'} +(S- { B}_{s } ) { U}_{w } } over { beta } , PHI = { { cpDU}_{ omega } } over {4 beta } }}}} where $\theta$$\omega$; discharged water temperature($^{\circ}C$) $\theta$a; air temperature ($^{\circ}C$) $\theta$$\omega$';ponded water temperature($^{\circ}C$) s ; net solar radiation(ly/min) t ; time(tadian) x; tube length(cm) D; diameter(cm) ao,an,bn;constants determined from $\theta$$\omega$(t) varitation. cp; heat capacity of water(cal/$^{\circ}C$ ㎥) U,Ua; overall heat transfer coefficient(cal/$^{\circ}C$ $\textrm{cm}^2$ min-1) $\omega$;1 velocity of water in a polyethylene tube(cm/min) Bs ; heat exchange rate between water and soil(ly/min)

• Applied Biological Chemistry
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• v.21 no.3
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• pp.150-184
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• 1978

Nutritional characteristics and physio-chemical properties of mycelial growth and fruitbody formation of oyster mushroom(Pleurotus ostreatus)in synthetic media, the curtural condition for the commerical production in the rice straw and poplar sawdust media, and the changes of the chemical components of the media and mushroom during the cultivation were investigated. The results can be summarized as follows: 1. Among the carbon sources mannitol and sucrose gave rapid mycelial growth and rapid formation of fruit-body with higher yield, while lactose and rhamnose gave no mycelial growth. Also, citric acid, succinic acid, ethyl alcohol and glycerol gave poor fruit-body formation, and acetic acid, formic acid, fumaric acid, n-butyl alcohol, n-propyl alcohol and iso-butyl alcohol inhibited mycelial growth. 2. Among the nitrogen sources peptone gave rapid mycelial growth and rapid formation of fruit-body with higher yield, while D,L-alanine, asparatic acid, glycine and serine gave very poor fruit-body formation, and nitrite nitrogens, L-tryptophan and L-tyrosine inhibited mycelial growth. Inorganic nitrogens and amino acids added to peptone were effective for fruit-body growth, and thus addition of ammonium sulfate, ammonium tartarate, D,L-alanine and L-leucine resulted in about 10% increase fruit-body yield. L-asparic acid about 15%, L-arginine about 20%, L-glutamic acid, and L-lysine about 25%. 3. At C/N ratio of 15.23 fruit-body formation was fast, but the yield decreased, and at C/N ratio of 11.42 fruit-body formation was slow, but the yield increased. Also, at the same C/N ratio the higher the concentration of mannitol and petone, the higher yield was produced. Thus, from the view point of both yield of fruit-body and time required for fruiting the optimum C/N ratio would be 30. 46. 4. Thiamine, potassium dihydrogen phosphate and magnecium sulfate at the concentration of $50{\mu}g%$. 0.2% and 0.02-0.03%, respectively, gave excellent mycelial and fruit-body growth. Among the micronutrients ferrous sulfate, zinc sulfate and manganese sulfate showed synergetic growth promoting effect but lack of manganese resulted in a little reduction in mycelial and fruit-body growth. The optimum concentrati on of each these nutrients was 0.02mg%. 5. Cytosine and indole acetic acid at 0.2-1mg% and 0.01mg%, respectively, increased amount of mycelia, but had no effect on yield of fruit-body. The other purine and pyrimidine bases and plant hormones also had no effect on mycelial and fruit-belly yield. 6. Illumination inhibited mycelial growth, but illumination during the latter part of vegetative growth induced primordia formation. The optimum light intensity and exposure time was 100 to 500 lux and 6-12 hours per day, respectively. Higher intensity of light was injurous, and in darkness only vegetative growth without primordia formation was continued. 7. The optimum temperature for mycelial growth was $25^{\circ}C$ and for fruit-body formation 10 to $15^{\circi}C$. The optimum pH range was from 5.0 to 6.5. The most excellent fry it-body formation were produced from the mycelium grown for 7 to 10 days. The lesser the volume of media, the more rapid the formation of fruit-body; and the lower the yield of fruit-body; and the more the volume of media, the slower the formation of fruit-body, and the higher the yield of fruit-body. The primordia formation was inhibited by $CO_2$. 8. The optimum moisture content for mycelial growth was over 70% in the bottle media of rice straw and poplar sawdust. 10% addition of rice bran to the media exhibited excellent mycelial growth and fruit-body formation, and the addition of calciumcarbonate alone was effective, but the addition of calcium carbonate was ineffective in the presence of rice bran. 9. In the cultivation experiments the total yield of mushroom from the rice straw media was $14.99kg/m^2$, and from the sawdust media $6.52kg/m^2$, 90% of which was produced from the first and second cropping period. The total yield from the rice straw media was about 2.3 times as high as that from the sawdust media. 10. Among the chemical components of the media little change was observed in the content of ash on the dry weight basis, and organic matter content decreased as the cultivation progressed. Moisture content, which was about 79% at the time of spawning, decreased a little during the period of mycelial propagation, after which no change was observed. 11. During the period from spawning to the fourth cropping about 16.7% of the dry matter, about 19.3% of organic matter, and about 40% of nitrogen were lost from the rice straw media; about 7.5% of dry mallet, about 7.6% of organic matter, and about 20% of nitrogen were lost from the sawdust media. For the production of 1kg of mushroom about 232g of organic matter and about 7.0g of nitrogen were consumed from the rice straw media; about 235g of organic matter and about 6.8g of nitrogen were consumed from the sawdust media, 1㎏ of mushroom from either of media contains 82.4 and 82.3g of organic matter and 5.6 and 5.4g of nitrogen, respectively. 12. Total nitrogen content of the two media decreased gradually as the cultivation progressed, and total loss of insoluble nitrogen was greater than that of soluble nitrogen. Content of amino nitrogen continued to increase up to the third cropping time, after which it decreased. 13. In the rice straw media 28.0 and 13.8% of the total pentosan and ${\alpha}$-cellulose, respectively, lost during the whole cultivation period was lost during the period of mycelial growth; in the sawdust media 24.1 and 11.9% of the total pentosan and ${\alpha}$-cellulose, respectively, was lost during the period of mycelial growth. Lignin content in the media began to decrease slightly from the second cropping time, while the content of reduced sugar, trehalose and mannitol continued to increase. C/N ratio of the rice straw media decreased from 33.2 at spawining to 30.0 at ending; that of the sawdust media decreased from 61.3 to 60.0. 14. In both media phosphorus, potassium, manganese and zinc decreased, at magnesium, calcium and copper showed irregular changes, and iron had a tendency to be increased. 15. Enzyme activities are much higher in the rice straw media than in the sawdust media. CMC saccharifying and liquefying activity gradually increased from after mycelial propagation to the second cropping, after which it decreased in both media. Xylanase activity rapidly and greatly increased during the second cropping period rather than the first period. At the start of the third cropping period the activity decreased rapidly in the rice straw media, which was not observed in the sawdust media. Protease activity was highest after mycelial propagation, after which it gradually decreased. The pH of the rice straw media decreased from 6.3 at spawning to 5.0 after fourth cropping; that of the sawdust media decreased from 5.7 to 4.9. 16. The contents of all the components except crude fibre of the mushroom from the rice straw media were higher than those from the sawdust media. Little change was observed in the content of the components of mushroom cropped from the first to the third period, but slight decrease was noticed at the fourth cropping.