• Journal of Microbiology
• /
• v.34 no.4
• /
• pp.384-386
• /
• 1996

Application of polyacrylamide gel (PAG) instead of agar to solid cultures of Streptomyces spp. was studied. The improved media were prepared by 1) gelling 20 ml of 5% acrylamide in a glass petri dish at room temperature, 2) washing by running water for more than 8 hr to remove residual reaction reagents, 3) drying at 5$0^{\circ}C$ for 12 hr to make a gel film, 4) autoclaving at 121$^{\circ}C$ for 15 min, and 5) swelling gel for about 4 hr by adding sterile liquid medium. In PAG media there were no differences from the observation of morphological characteristics showing during the cellular differentiation on agar media, whereas the ability to utilize carbohydrates differed somewhat from agar media. Agar media thus were little favorable for biochemical tests which the growth was determined depending on the formation of colony, but washed PAG was superior to serve as a solidifying agent.

• Journal of Mushroom
• /
• v.17 no.3
• /
• pp.99-106
• /
• 2019

To improve the productivity of shiitake mushroom (Lentinula edodes), seven different types of media for liquid spawn (denoted as "A" to "G") were prepared with 0.3% soybean meal and varying sugar and glucose concentrations. During 14 days of incubation, the pH of the liquid culture gradually acidified with increasing incubation period. Additionally, there was a significant, but not prominent, difference in the degree of acidification depending on the sugar to glucose ratio. Liquid spawn culture "G," which had the highest sugar content was the most acidic on the last day of incubation. Mycelium dry weight increased significantly with increasing incubation period, and there was no significant difference in mycelium dry weight irrespective of the sugar to glucose ratio even after 14 days of culture. The inoculation of liquid spawn in sawdust medium with an inoculation volume ${\geq}45mL$ and incubation period of 15 to 18 days were the optimal culture conditions. Productivity of fruit bodies in sawdust medium and mushrooms treated with liquid spawn was significantly higher compared to solid spawn treatment. The mushrooms treated with liquid spawn had better chewiness, and the free amino acid content, which is associated with savory taste, was higher in these mushrooms compared to those treated with solid spawn.

• Tuberculosis and Respiratory Diseases
• /
• v.79 no.4
• /
• pp.282-288
• /
• 2016

Background: Tuberculosis (TB) is a major health problem, and accurate and rapid diagnosis of multidrug-resistant (MDR) and extended drug-resistant (XDR) TB is important for appropriate treatment. In this study, performances of solid and liquid culture methods were compared with respect to MDR- and XDR-TB isolate recovery and drug susceptibility testing. Methods: Sputum specimens from 304 patients were stained with Ziehl-Neelsen method. Mycobacterium tuberculosis (Mtb) isolates were tested for recovery on $L{\ddot{o}wenstein$-Jensen (LJ) medium and the BacT Alert 3D system. For drug susceptibility testing of Mtb, isolates were evaluated on M-KIT plates and the BacT Alert 3D system. Results: The recovery rates were 94.9% (206/217) and 98.2% (213/217) for LJ medium and the BacT Alert 3D system, respectively (kappa coefficient, 0.884). The rate of drug resistance was 13.4% for at least one or more drugs, 6.0% for MDR-TB and 2.3% for XDR-TB. M-KIT plate and BacT 3D Alert 3D system were comparable in drug susceptibility testing for isoniazid (97.7%; kappa coefficient, 0.905) and rifampin (98.6%; kappa coefficient, 0.907). Antibiotic resistance was observed using M-KIT plates for 24 of the total 29 Mtb isolates (82.8%). Conclusion: The liquid culture system showed greater reduction in the culture period, as compared with LJ medium; however, drug susceptibility testing using M-KIT plates was advantageous for simultaneous testing against multiple drug targets.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.1
• /
• pp.33-36
• /
• 1998

Guzmania was propagated through in vitro culture of lateral shoots. When new shoots grown in greenhouse were cut and cultured in vitro, contamination rate was very high at about 80% in the first stage of in vitro culture. Among cytokinin treatments for agar medium, 2.0 mg/L BA was most effective for shoot multiplication, and those with 0.5 mg/L kinetin and 0.5~1.0 mg/L BA were favorable for shoot multiplication. BA was more effective for shoot multiplication than kinetin, and shoot multiplication was more enhanced when 2.0 mg/L BA was combined with 0.1~0.5 mg/L IAA than 2.0 mg/L BA alone. The medium with 2.0 mg/L BA and 0.1 mg/L IAA showed the highest rate of shoot multiplication with about 8.7 in shoot number, and those with 2.0 mg/L BA and 0.5~1.0 mg/L IAA also resulted in high multiplication of shoots. Shoots were multiplicated more in liquid rotation culture(80 rpm) with the medium containing 0.5 mg/L BA and 0.1 mg/L IAA than liquid stagnating and solid cultures. Regenerated shoots formed roots very favorably in the medium supplemented with 2.0 mg/L IBA.

• Environmental Analysis Health and Toxicology
• /
• v.14 no.4
• /
• pp.145-153
• /
• 1999

Effects of various concentrations of copper in solid fibrous form and methylglyoxal (MG) on phosphorus uptake and growth change of green algae Scenedesmus obliquus were studied. There was significant differences among cultures treated with various concentrations of copper and MG in growth of algae with parameters of cell numbers, photosynthetic rate and cellular morphology, and phosphorus uptake by cell. When the copper in media is treated with 25 mg or 50 mg per 100 ml of Bristol solution, the mean cell number of algae was 15.642${\times}$10$\^$6/ cells$.$ml$\^$-1/ and 12.986${\times}$10$\^$6/ cells$.$ml$\^$-1/, respectively, while those of algae in culture without copper was 18.486${\times}$10$\^$6/ cells$.$ml$\^$-1/. The mean cell area of 2450 ${\mu}$m$^2$, 1894 ${\mu}$m$^2$and 1697 ${\mu}$m$^2$in basic media, basic media with 25 mg of copper and basic media with 50 mg of copper was showed the inhibitory effect of copper on algal growth. The algal growth was stimulated by MG when the culture was treated with 25 mg of copper or without copper, while it was inhibited when the culture was treated with 50 mg of copper. It was considered that there was significant interaction between copper and MG on algal growth. The phosphorus concentration in algal medium treated with 25 mg or 50 mg of copper was 29.435 ppm and 26.224 ppm, respectively, while those of algae in culture without copper was 52.8 ppm, which shows that the application of copper in algal medium can prevent the availability of phosphorus to algal cell.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.3
• /
• pp.189-195
• /
• 1999

This study was carried out to clarify several factors affecting embryogenesis from anther culture of nine cultivars in Brassica oleracea L. var. italica and to investigate the characteristics of plants derived from anther culture. Androgenesis from anther culture was elevated on the B5 medium supplemented with 0.1mg/L NAA, 0.1mg/L 2.4-D and 10% sucrose. Embryo production in liquid medium was five-fold higher than solid medium. High temperature treatment at 35$^{\circ}C$ for one day before transfer to culture room maintained at $25^{\circ}C$ had effective to induce embryogenesis of cultured anthers but extended treatment at 35$^{\circ}C$ decreased significantly the percent of embryogenesis. Frequency of embryogenesis from cultured anthers exhibited significant difference from 2.8% in 'Green Valiant' to 21% in 'Haisi' as affected by genotypes. Percent of spontaneously dihaploid among regenerated plants from anther culture was ranged from 62 to 74% as affected by the genotypes. Characteristic in relation to plant height, number of leaves and branches, and size of head from anther-derived plants showed differential variation in 'Rokguray' and 'Haisi'. Among these charaters obtained from two cultivars, five lines were selected for early maturity, long plant height and large head. Selected lines were used as breeding meterials for F$_1$ hybrid.

• Microbiology and Biotechnology Letters
• /
• v.32 no.2
• /
• pp.184-189
• /
• 2004

Rice wine cake (RWC) is the solid waste obtained after rice wine fermentation. For the mass production of the spores of yeast Saccharomyces from RWC, the optimum pretreatment condition of RWC, the optimum composition of culture medium, and the optimum culture condition were examined. For sporulation, yeast cells were grown in the pre sporulation medium (PSM), transferred into sporulation medium (SM) containing 1 % potassium acetate, and incubated in a rotary shaking incubator at $25^{\circ}C$ for 4 days. The supernatant of the mixture of RWC and water was used as the presporulation medium (PSM). The optimum temperature and time for the pre-incubation of the mixture of RWC and water (1:2) to obtain maximum sporulation yield were $V^{\circ}C$ and 24 hr, respectively, and optimum culture time in PSM was 48 hr. Using these optimum conditions, the asci number obtained was 0.72$ 1.06${\times}$10^{8}$$m\ell$. The addition of wheat coat koji into SM increased the final number of asci to beTEX>$10^{8}$ $m\ell$. Spores were formed in the SM with the initial pH of 7-11, but no spores were formed in the SM with the initial pH of 5. To save the time and effort to pretreat the RWC, 2% and 0.5% RWC without any pretreatment were directly added into PSM containing 1 % brown sugar and SM, respectively, and the maximum asci number of $1.27${\times}$10^{8}$ /$m\ell$ was obtained.

• FLOWER RESEARCH JOURNAL
• /
• v.18 no.3
• /
• pp.179-185
• /
• 2010

This study was carried out to investigate the optimal culture conditions for gametophytes growth and sporophytes regeneration of Pyrrosia linearifolia in order to provide for the masspropagation system foundation of Pyrrosia linearifolia using their life cycle. Among many different media, 2MS medium was most effective in prothallus proliferation. Prothallus growth was promoted as the total concentration of nitrogen sources increased, and the best result was observed on 120 mM nitrogen. The best concentration of sucrose was 3%. The addition of 5~20 mM IAA, NAA, BA and kinetin promoted the propagation of prothallus. But 2iP demonstrated the most inhibitory effect on prothallus proliferation. Gametophytes shaking-cultured with liquid medium showed similar growth with solid medium and normal formation of reproductive organs. Shoot regeneration was most effective on 1/8MS medium, but growth was promoted on 1/2MS medium. For promotion of shoot regeneration and growth, the suitable concentrations of sucrose and $NaH_2PO_4$ were 1% and $50{\sim}100mg{\cdot}mL^{-1}$ in 1/8MS medium, respectively.

• Journal of Bio-Environment Control
• /
• v.29 no.1
• /
• pp.1-8
• /
• 2020

The influence of growth regulators (NAA and BA) and sucrose concentrations (0, 3, 5, 7, 9%) on in vitro rapid-propagation of virus-free sweet potato [Ipomoea batatas (L.) Lam.] was investigated with single-node or shoot-tip culture of two cultivars ('Matnami' and 'Shinhwangmi'). The survival rate and growth of shoot-tip explant was also investigated under the presence or absence of light (blue and red LED = 7:3, 150±5 μmol·m^-2·s^-1 PPFD) during minimal-growth in vitro conservation at 15℃. Vine length, vine diameter, fresh weight and dry weight were enhanced without callusing of explant in the MS medium supplemented with 0.2-0.5 mg·L^-1 BA. The growth of single-node and shoot-tip explants were significantly enhanced with the increase of vine length, number of leaf, number of root, fresh weight, and dry weight in the solid medium containing 5% sucrose and 0.2 mg·L^-1 BA. Vine elongation of shoot-tip explants were highest in the liquid medium containing 3% sucrose than the solid medium. The survival rate of minimal-growth in vitro conservation was 100% in 5 months under the presence of light (LED, 150±5 μmol·m^-2·s^-1 PPFD) at 15℃, but the explants in dark condition died in 3 months. The light was absolutely necessary for the in vitro conservation under minimal-growth conditions of virus-free sweet potato plantlets at 15℃, and the high density of explants (10 plantlets per Petri Dish) was increased the efficiency of mass conservation.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.11
• /
• pp.1865-1875
• /
• 2018

Enhanced application of solid-state fermentation (SSF) in industrial production and the influence of SSF of Rhizopus K1 on glucoamylase productivity were analyzed using the flat band method. A growth model was implemented through SSF of Rhizopus K1 in this experiment, and spectrophotometric method was used to determine glucoamylase activity. Results showed that in bran and potato culture medium with 70% moisture in a loose state, ${\mu}$ of mycelium reached to $0.15h^{-1}$ after 45 h of culture in a thermostatic water bath incubator at $30^{\circ}C$. Under a low-magnification microscope, mycelial cells appeared uniform, bulky with numerous branches, and were not easily ruptured. The generated glucoamylase activity reached to 55 U/g (dry basis). This study has good utilization value for glucoamylase production by Rhizopus in SSF.