401
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Park EY, Hamanaka T, Higashiyama K, Fujikawa S. Monitoring of morphological development of the arachidonic-acid-producing filamentous microorganism Mortierella alpina. Appl Microbiol Biotechnol 2002; 59:706-12. [PMID: 12226728 DOI: 10.1007/s00253-002-1089-2] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2002] [Revised: 06/28/2002] [Accepted: 07/07/2002] [Indexed: 11/24/2022]
Abstract
Morphological parameters, such as hyphal growth rate, tip formation rate, tip extension rate and branch formation rate, of Mortierella alpina have been measured using a flow-through chamber under 25 different combinations of carbon and nitrogen concentrations. Morphological parameters were influenced not by C/N ratio but by carbon concentration in the medium. Specific rates of hyphal growth and tip formation both remained constant at a low carbon concentration of 5 g/l. Tip extension rate from one tip was 60 microm tip(-1) h(-1) at a carbon concentration below 15 g/l, and the branching formation rate was independent of carbon concentration. Tip extension rate was a function of specific hyphal growth rate, which in turn was linearly proportional to the specific tip formation rate, demonstrating that tip extension rate was exponentially proportional to the specific tip formation rate. Branch formation rate per hyphal element remained unchanged even at tip extension rates lower than 60 microm tip(-1) h(-1) and at specific hyphal growth rates lower than 0.83 h(-1), but decreased drastically at higher rates of tip extension and hyphal growth.
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Affiliation(s)
- E Y Park
- Laboratory of Biotechnology, Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
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402
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Abstract
BACKGROUND The quality of sexuality is significantly affected by physical changes following hematopoietic stem cell transplantation (HSCT) and the dissatisfied and/or dysfunctional sexuality may cause deterioration in the quality of life (QOL). METHODS With two models of questionnaires, we interviewed thirty-eight patients who remained in the disease-free status after HSCT and had sex partners, to assess: 1) the changes in sexuality, 2) QOL in physical, psychological, social and spiritual domains and 3) the correlation between sexuality and QOL. RESULTS The common physical changes that may affect sexuality in women were secondary amenorrhea (69.2%), loss of sexual interest (53.8%), diminished vaginal secretion (50%), menopausal syndrome (34.6%), dyspareunia (30.8%) and failure to orgasm (23.1%), while men complained of impotence (41.7%) and difficulty in ejaculation (16.7%). For sexuality, satisfaction of sexual activity, attainment of orgasm and frequency of intercourse decreased significantly after HSCT as compared with the pre-transplant levels. A score measuring, QOL after HSCT marked 5.91 on a full score of 10; social domain ranked the lowest (5.01) while physical domain the highest (6.70). Among the items of sexuality, only sexual desire was significantly correlated with QOL; satisfaction, orgasm and frequency were not significantly correlated with QOL. CONCLUSION Although sexuality is affected by the physical changes following HSCT, we should not overlook the psychological and social effects on the sexuality of post-transplant patients. Therefore, educational and counseling programs are very important to restore and improve their sexuality.
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Affiliation(s)
- Hong Ghi Lee
- Departments of Medicine, Hematology and Oncology, Samsung Medical Center, Sungkyunkwan University College of Medicine, 50 Ilwon-Dong, Kangnam-Ku, Seoul 135-710, Korea
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403
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Abstract
Nociceptin (N/OFQ) is a novel heptadecapeptide with an amino acid sequence similar to that of endogenous opioid peptide dynorphin A. Dynorphin have been reported to increase the secretion of atrial natriuretic peptide (ANP) via selective activation of kappa-opioid receptor in cultured atrial cardiocytes. The present study was designed to investigate the direct effect of N/OFQ on the ANP secretion in cultured neonatal rat cardiac myocytes via N/OFQ receptor (NOP) activation. The secretion of ANP from cultured neonatal cardiac myocytes was increased in terms of incubation time. N/OFQ, at a dose of 0.3, 1, 3, and 10 microM, caused increases in ANP secretion in a dose-dependent manner. The N/OFQ-induced ANP secretion was completely antagonized by antagonists of NOP, 1 microM each of [Phe1 (CH2-NH) Gly2] nociceptin (1-13)-NH2 ([FG]N/OFQ(1-13)NH2) or naloxone benzoylhydrazone. In contrast, naloxone (1 microM), the non-selective opioid receptor antagonist, did not alter ANP response to N/OFQ. N/OFQ at 3 microM inhibited basal and forskolin-stimulated cAMP production, which was partially antagonized with the pretreatment of [FG]N/OFQ(1-13)NH2. An increase in ANP secretion by N/OFQ was also partially blocked by the pretreatment of forskolin. Homologous competition studies in neonatal cardiomyocyte membranes revealed the presence of two distinct sites. The high affinity site (10.9 +/- 1.6 nM) was far less abundant than the low affinity site. Therefore, these results suggest that N/OFQ causes an increase in ANP secretion in cultured neonatal cardiac myocytes by decreasing cAMP through its binding sites.
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Affiliation(s)
- K W Kim
- Department of Physiology, Medical School and Institute for Medical Sciences, Chonbug National University, Chonju, Korea
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404
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405
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406
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Hwang KJ, Lee TS, Kim KW, Kim BT, Lee CM, Park EY, Woo RS. 4-Hydroxy-6-oxo-6,7-dihydro-thieno[2,3-b] pyrimidine derivatives: synthesis and their biological evaluation for the glycine site acting on the N-methyl-D-aspartate (NMDA) receptor. Arch Pharm Res 2001; 24:270-5. [PMID: 11534755 DOI: 10.1007/bf02975090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Bioisostere approach has been shown to be useful to augment potency or to modify certain physiological properties of a lead compound. Based upon well documented bioisosterism, an isosteric replacement of benzene ring of 4-hydroxy-2-quinolone compound (L-695902) with a thiophene moiety was carried out to prepare the title compounds, 4-hydroxy-6-oxo-6,7-dihydro-thieno[2,3-b] pyrimidines 15. The resulting bioisosteric compounds 15 were evaluated for their antagonistic activity (binding assay) for NMDA receptor glycine site.
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Affiliation(s)
- K J Hwang
- Department of Chemistry and Research Center of Bioactive Materials, College of Natural Science, Chonbuk National University, Chonju, Korea.
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407
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Hamanaka T, Higashiyama K, Fujikawa S, Park EY. Mycelial pellet intrastructure and visualization of mycelia and intracellular lipid in a culture of Mortierella alpina. Appl Microbiol Biotechnol 2001; 56:233-8. [PMID: 11499936 DOI: 10.1007/s002530100649] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intrastructure of mycelial pellets of Mortierella alpina, which accumulate fatty acids in mycelia, was visualized following labeling with fluorescein isothiocyanate (FITC) and Nile red using fluorescence microscopy. The pellet was an ellipse shape, but its intrastructure was shaped as a doughnut with a cave inside. Using three-dimensional image analysis, it was shown that the lipid was produced on the edge of the pellet, which corresponded to the area where the mycelial density was high. The cavity ratio of the pellet section was determined on the basis of the FITC fluorescence intensity, and in the early culture stage remained at 0.2 in a 10-kl fermentor culture, but finally increased to 0.35. Mycelial pellet volume paralleled the cavity ratio. Application of the technique used here allows analysis of the intrastructure of fungal pellets and new types of fungal biological study.
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Affiliation(s)
- T Hamanaka
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, Ohya, Japan
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408
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Kang WK, Park C, Yoon HL, Kim WS, Yoon SS, Lee MH, Park K, Kim K, Jeong HS, Kim JA, Nam SJ, Yang JH, Son YI, Baek CH, Han J, Ree HJ, Lee ES, Kim SH, Kim DW, Ahn YC, Huh SJ, Choe YH, Lee JH, Park MH, Kong GS, Park EY, Kang YK, Bang YJ, Paik NS, Lee SN, Kim SH, Kim S, Robbins PD, Tahara H, Lotze MT, Park CH. Interleukin 12 gene therapy of cancer by peritumoral injection of transduced autologous fibroblasts: outcome of a phase I study. Hum Gene Ther 2001; 12:671-84. [PMID: 11426466 DOI: 10.1089/104303401300057388] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
A phase I dose-escalation clinical trial of peritumoral injections of interleukin 12 (IL-12)-transduced autologous fibroblasts was performed in patients with disseminated cancer for whom effective treatment does not exist. The goals of this study were to assess the safety and toxicities as well as the efficacy, and ancillarily the immunomodulatory effects, of peritumoral IL-12 gene transfer. Primary dermal fibroblasts cultured from the patients were transduced with retroviral vector carrying human IL-12 genes (p35 and p40) as well as the neomycin phosphotransferase gene (TFG-hIL-12-Neo). Patients received four injections at intervals of 7 days. Nine patients were enrolled in this dose-escalation study, with secreted IL-12 doses ranging from 300 ng/24 hr for the first three patients to 1000, 3000, and 5000 ng/24 hr for two patients in each subsequent dosage level. Although a definite statement cannot be made, there appears to be perturbation of systemic immunity. Also, the locoregional effects mediated by tumor necrosis factor alpha (TNF-alpha) and CD8+ T cells were observed with tumor regression. Treatment-related adverse events were limited to mild to moderate pain at the injection site; clinically significant toxicities were not encountered. Transient but clear reductions of tumor sizes were observed at the injected sites in four of nine cases, and at noninjected distant sites in one melanoma patient. Hemorrhagic necrosis of tumors was observed in two melanoma patients. These data indicate that gene therapy by peritumoral injection of IL-12-producing autologous fibroblasts is feasible, and promising in patients with advanced cancer.
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Affiliation(s)
- W K Kang
- Cancer Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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409
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Cho US, Ahn HJ, Park EY, Dong MS, Kim KH. Influence of ligand binding to human cytochrome P-450 1A2: conformational activation and stabilization by alpha-naphthoflavone. Biochim Biophys Acta 2001; 1546:412-21. [PMID: 11295446 DOI: 10.1016/s0167-4838(01)00165-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human cytochrome P-450 (P-450) 1A2 expressed in Escherichia coli is readily converted into non-native cytochrome P-420 (P-420) in the presence of detergents. alpha-Naphthoflavone (ANF) has been used to prevent P-450 1A2 inactivation to P-420 during purification. However, the mechanism by which ANF modulates P-450 1A2 is not clearly understood. We observed that recombinant human P-450 1A2 prepared in the absence of ANF has an approx. 5 times higher maximum catalytic activity in the O-deethylation of 7-ethoxycoumarin than that in the presence of ANF, with the same K(m) values. The results revealed that the enzyme purified with ANF is not catalytically fully active, indicating that ANF tightly binds to the enzyme, only to be dissociated by heat denaturation. Furthermore, the inactive P-420 form of the enzyme could be reconverted to P-450 by ANF in high concentrations of detergents. The reconversion was concentration-dependent, confirming ANF-induced regeneration of active P-450 1A2. The reconversion coincided with the conformational change of the enzyme including increased alpha-helix content. The conformation of P-450 1A2 was also stabilized by ANF, resulting in an approx. 5 degrees C increase in thermal stability.
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Affiliation(s)
- U S Cho
- Graduate School of Biotechnology, Korea University, 136-701, Seoul, South Korea
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410
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Abstract
Enzymatic hydrolysis of waste office (WO) paper with feeding WO paper in a reactor was investigated using apparent viscosity as operating parameter. Since the apparent viscosity was correlated with the concentration of pulping WO paper, the amount of hydrolyzed WO paper was assumed by measuring the decrease in the apparent viscosity. Then the amount of hydrolysis WO paper and the amount of enzyme corresponding to the desired ratio were fed into the reactor. When the WO paper and 1% (to the amount of WO paper) enzyme were fed to the hydrolytic reaction, 87 g/L of reducing sugar (RS) with a hydrolytic yield of 42.2% was obtained for a 24-h hydrolysis. However, when nonpulping WO paper and 5% (to the amount of WO paper) enzyme were fed to the hydrolytic reaction, 120 g/L of RS with a hydrolytic yield of 40% was obtained for a 24-h hydrolysis. Therefore, the RS concentration from this hydrolysis process feeding WO paper using apparent viscosity as operating parameter may be of sufficient concentration to serve as a carbon source in microorganism culture or chemical feedstock.
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Affiliation(s)
- E Y Park
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
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411
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Abstract
OBJECTIVES To determine whether irregularity, and short- and long-term fractal correlation reflecting smoothness of heart rate behavior are changed in intrauterine growth restricted fetuses. STUDY DESIGN Fetal heart rate data of 192 normal fetuses and 86 intrauterine growth restricted fetuses between 31 and 42 weeks of gestation were studied. Approximate entropy to quantify irregularity, and short-term (< or =80 beats, alpha1) and long-term (>80 beats, alpha2) fractal scaling exponents to quantify the short- and long-term fractal correlation were calculated. RESULTS In the intrauterine growth restricted fetuses, the approximate entropy was significantly lower (P<0.001). The alpha2 value was significantly higher (P=0.0001) than in the normal fetuses, which performed better (F=34.2, P<0.0001) than other heart rate variability indexes in differentiating the intrauterine growth restricted fetuses from the normal fetuses in stepwise discriminant analysis. CONCLUSIONS Compared to normal fetuses, intrauterine growth restricted fetuses show a difference in that the irregularity of the fetal heart is decreased. A more apparent difference is that the long-term fractal correlation of the fetal heart is increased and the fetal heart is smoother in the long-term scale.
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Affiliation(s)
- M K Yum
- Department of Pediatric Cardiology, Hanyang University School of Medicine, 17 Haengdang-dong Sungdong-ku, 133-792, Seoul, South Korea.
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412
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Choi DB, Park EY, Okabe M. Dependence of apparent viscosity on mycelial morphology of Streptomyces fradiae culture in various nitrogen sources. Biotechnol Prog 2000; 16:525-32. [PMID: 10933823 DOI: 10.1021/bp000056x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To examine what causes increased viscosity in culture broth in Streptomyces fradiae culture, various natural nitrogen sources were investigated. Extracellular protease activity increased with culture time and decomposed the natural nitrogen source into amino acids. In the case of gluten meal, after a culture time of 5 d, concentrations of glutamic acid and aspartic acid had increased to 600 and 200 mg/L, respectively, which were about 3- and 2-fold as high as levels in cultures under similar conditions using Pharmamedia. For various amino acids tested, the addition of glutamic acid or aspartic acid mixture to the culture medium raised the apparent viscosity to its highest demonstrated value, 260 mPa.s after 5 d of culture, which was 3-fold higher than without amino acids. Consumption of the decomposed glutamic acid and aspartic acid was dependent on the activities of glutamate dehydrogenase and aspartate aminotransferase, respectively. When ammonium ion was used as the nitrogen source, cell concentration reached 1.75 g/L measured as an intracellular nucleic acid concentration, which was about 2.3-fold higher than that with any other natural nitrogen source. However, apparent viscosity was only 75 mPa.s, a value one-third that of the amino acid mixture, and 70% of the pellets were bigger than 1.2 x 10(4) microm(2). In the case of gluten meal or the amino acid mixture, pellets bigger than 1.2 x 10(4) microm(2) comprised only 8%. This demonstrates that consumption of some amino acids affected the formation of filamentous morphology, which caused an increase in the apparent viscosity of the culture broth, and the apparent viscosity was not caused by the mycelial concentration but the mycelial morphology.
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Affiliation(s)
- D B Choi
- Institute of Life Science, Chosun University, 375, Seo-Suk Dong, Dong-ku, Kwang-Ju, Korea
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413
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Park EY, Ichida M, Kahar P, Okabe M. Kinetics of soybean oil consumption and cephamycin C production in culture of streptomyces sp. using mineral support. J Biosci Bioeng 1999; 87:390-3. [PMID: 16232488 DOI: 10.1016/s1389-1723(99)80052-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/1998] [Accepted: 11/18/1998] [Indexed: 11/22/2022]
Abstract
A simple kinetics of soybean oil consumption and cephamycin C production in Streptomyces sp. culture using a mineral support is proposed in this study. The mineral support was used for both suspending the soybean oil as fine oil droplets and immobilizing mycelia. The optimum concentrations of oil and mineral support for obtaining the maximum cephamycin C production were determined to be 50 and 15 g/l, respectively, by the proposed kinetics. At the optimal concentrations, the concentration of cephamycin C estimated from the proposed model and from the experimental data was 2.82 and 2.80 g/l, respectively. The results of the simulation coincided well with the experimental data for various concentrations of the soybean oil and the support. This demonstrates that our model can explain the kinetics of a culture using vegetable oil as the carbon source and mineral support for both oil suspension and mycelial immobilization.
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Affiliation(s)
- E Y Park
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan
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414
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Park EY, Koike Y, Higashiyama K, Fujikawa S, Okabe M. Effect of nitrogen source on mycelial morphology and arachidonic acid production in cultures of mortierella alpina. J Biosci Bioeng 1999; 88:61-7. [PMID: 16232575 DOI: 10.1016/s1389-1723(99)80177-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/1998] [Accepted: 04/14/1999] [Indexed: 10/18/2022]
Abstract
The effects of nitrogen source on arachidonic acid (AA) production and morphological changes during the culture of Mortierella alpina were investigated using an image analysis system. When yeast extract, gluten meal, or corn steep liquor was used, a circular pellet morphology was obtained. However, when Pharmamedia, fish meal, or soybean meal was used, M. alpina formed radial filamentous mycelia. The radial filamentous area in the case of soybean meal was 75% of the total mycelial area. In a jar fermentor culture, M. alpina morphology varied with the cultivation period: (i) at 0-6 h culture, the inoculated pellet-like mycelia were adapted to the new environment, (ii) at 6 h-1 d culture, filamentous mycelia grew exponentially which yielded a feather-like morphology, (iii) at 1-2 d culture, the filamentous mycelia became disentangled as a result of the mechanical agitation; consequently, the proportion of filamentous mycelia was increased, (iv) at 2-4 d culture, mycelia showed stationary growth, but the AA concentration increased rapidly, and (v) at 4-6 d culture, hyphae grew thick radially with the AA concentration continuing to increase gradually. In the case of the cultures with feather-like morphology obtained using soybean meal, the AA yield was 0.14 g/g dry cell weight, which was two times higher than that in cultures grown using yeast extract. These results suggest that the feather-like morphology of culture of M. alpina is suitable for AA production.
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Affiliation(s)
- E Y Park
- Laboratory of Biotechnology, Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529 Japan
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415
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Higashiyama K, Fujikawa S, Park EY, Okabe M. Image analysis of morphological change during arachidonic acid production by Mortierella alpina 1S-4. J Biosci Bioeng 1999; 87:489-94. [PMID: 16232503 DOI: 10.1016/s1389-1723(99)80098-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/1998] [Accepted: 12/24/1998] [Indexed: 11/26/2022]
Abstract
The changes in mycelial morphology during arachidonic acid (AA) production by Mortierella alpina 1S-4 were investigated using an image analysis system. Cultivation was performed in a 10-kl fermentor, and the culture broth was separated into two fractions by sieving (0.5 mm aperture size): the filament fraction (F-fraction, <0.5 mm), and the pellet fraction (P-fraction, >0.5 mm). The effect of the mycelial morphology in each fraction on AA production was analyzed. As a result, a product distribution in the culture broth wherein the AA content in the mycelia of the P-fraction was observed to be higher than that in the mycelia of the F-fraction throughout the cultivation. Morphological analysis of the P-fraction revealed that the hairy pellets became smooth because the mycelia on the pellet surface were shaved off; some pellets were broken and reduced in size. The shaved-off mycelia from the hairy pellets surface moved into the F-fraction and aggregated there. From the above findings, it was likely that the low AA content in the F-fraction was due to mycelial damage during the cultivation. In addition, the morphology of the hairy pellets was found to contribute to an increase in the viscosity of culture broth.
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Affiliation(s)
- K Higashiyama
- Institute for Fundamental Research, Suntory Limited, 5-2-5 Yamazaki, Osaka 618-0001, Japan
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416
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Park EY, Kosakai Y, Okabe M. Efficient production of L-(+)-lactic acid using mycelial cotton-like flocs of Rhizopus oryzae in an air-lift bioreactor. Biotechnol Prog 1998; 14:699-704. [PMID: 9758658 DOI: 10.1021/bp9800642] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
L-(+)-Lactic acid production was enhanced in a culture of Rhizopus oryzae by induction of a mycelial flocs morphology. By conventional culture the morphology of R. oryzae is that of a pellet-like cake; however, when mineral support and poly(ethylene oxide) are added to the culture, the morphology of R. oryzae takes on a cotton-like appearance. The formation of these cotton-like mycelial flocs was induced by the addition of 5 ppm poly(ethylene oxide) into a 12-14 h culture containing 3 g/L of the mineral support before the formation of the conventional pellet morphology. The cotton-like flocs were also formed in cultures grown in an air-lift bioreactor. This morphology allowed effective mass transfer inside the flocs and effective fluidity of culture broth in an air-lift bioreactor. L-(+)-Lactic acid concentration produced by mycelial flocs in an air-lift bioreactor, with the support and poly(ethylene oxide), was 104.6 g/L with a yield of 0.87 using 120 g/L of glucose as the substrate; for this culture without both, the concentration was 43.2 g/L. These results demonstrate that cotton-like mycelial flocs are the optimal morphology for use in the air-lift bioreactor culture of R. oryzae.
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Affiliation(s)
- E Y Park
- Laboratory of Biotechnology, Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
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417
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Affiliation(s)
- R J Salm
- Department of Podiatric Surgery, Fountain Valley Regional Hospital, CA 92708, USA
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418
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Abstract
Large defects on the plantar aspect of the foot can be too extensive to permit primary repair by suturing alone. Such defects can be closed through the use of skin flaps. The authors present an overview of skin flaps and suggest a transpositional skin flap as one type of reconstructive treatment for this problem.
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Affiliation(s)
- E Y Park
- Department of Podiatric Surgery, Fountain Valley Regional Hospital, California, USA
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