• Journal of Microbiology and Biotechnology
• /
• v.5 no.4
• /
• pp.234-237
• /
• 1995

Production of new flavanol derivatives with cytotoxic activity, gericudranin A and B, was studied by using hairy root cultures of Cudrania tricuspidata. Schenk and Hildebrandt (SH) medium was chosen for root growth and gericudranin production. After 35 days culture in a half-strength liquid SH medium containing $30g^{glucose}$/l, hairy root growth reached $138g^{FW}$/I and gericudranin A and B were produced at concentrations of 27mg/l and 21 mg/l, respectively. It was also observed that the contents of gericudranin A and B in hairy root were eight and six times higher than those of cudraniae radix, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.7
• /
• pp.728-733
• /
• 2011

Endophytic fungi, isolated from a number of different species of tropical plants, were investigated for lipid biodiesel precursor production. The extracts produced from liquid cultures of these fungi were subjected to acidcatalyzed transesterification reactions with methanol producing methyl esters and then analyzed through chromatographic (GC-FID) and spectrometric techniques (MS, NMR $^1H$). The European Standard Method, EN 14103, was used for the quantification of methyl esters extracted from the fungi of the species and genera studied. Xylariaceous fungi exhibited the highest concentrations of methyl esters (91%), and hence may be a promising source for biofuel.

• Journal of Food Hygiene and Safety
• /
• v.8 no.1
• /
• pp.55-61
• /
• 1993

Soil samples and the intestinal contents of arthropods, mollusca, pisces, aves, and mammals were examined for the presence of Clostridium botulinum. Demonstration of Clostridium botulimun was accomplished by identifying its toxin in liquid cultures inoculated with soil or material from the alimentary tract of tested animals with toxin neutralization tests in addition to morphological, cultural and biochemical tests. Incidences of Clostridium botulinum in tested samples were 5.0% in soil, 6.7% in mammal and 8.7% in fish, respectively. All of the positive cultures were identified as Clostridium botulinum type E and any other type was not demonstrated throughout the survey. Canned foods and solid ham/sausage mixture formulated as can with distilled water were inoculated with Clostridium botulinum type E and checked for toxin production by using the mouse bioassay. Clostridium botulinum type E toxin was produced as a large quantity in canned foods of fish, shell, meat and ham and, however, no significant toxin was detected in sausages and fruit samples.

• Journal of Microbiology and Biotechnology
• /
• v.11 no.1
• /
• pp.40-49
• /
• 2001

The present work presents a novel approach for the dynamic quantification of respiration rates on a small scale by using lysine-producing Corynebacterium glutamicum ATCC 21253. Cells sampeld from batch cultures at different times were incubated ina 12-ml scale bioreactor equipped with a membrane mass spectrometer. Under dynamic conditions, gas exchange across the gas-liquid phase, specific respiration rates, and RQ values were precisely measured. For this purpose, suitable mass balances were formulated. The transport coefficients for $O_2$ and $CO_2$, crucial for calculating the respiration activity, were determined as $k_La_{O2}=9.18h^{-1}$ and $k_La_{CO2}=5.10h^{-1}$ at 400 rpm. The application of the proposed method to batch cultures of C. glutamicum ATCC 21253 revealed the maximum specific respiration rates of $q_{O2}=8.4\;mmol\;g^{-1}h^{-1}\;and\;q_{CO2}=8.7\;mmol\;g^{-1}h^{-1}$ in the middle of the exponential growth phase after 5 h of cultivation. When the cells changed from growth to lysine production due to the depletion of the essential amino acids theonine, methionine, and leucine, $q_{O2}\;and\;q_{CO2}$ decreased significantly and RQ increased. The respiration data exhibited an excellent agreement with previous cultivations of the strain [13]. This confirms the potential of the developed approach to realistically reflect the metabolic activities of cells at their point of sampling. The short-term influence of added threonine, methionine, and leucine was highest during the shift from growth to lysine production, where $q_{O2}\;and\;q_{CO2}$ increased 50% within one minute after the pulse addition of these compounds. Non-growing, yet lysine-producing cells taken from the end of the batch cultivation revealed no metabolic stimulation with the addition of threonine, methionine, and leucine.

• Journal of Plant Biotechnology
• /
• v.34 no.3
• /
• pp.207-212
• /
• 2007

This study describes a simple and rapid method for quantitative determination of $\gamma$-aminobutyric acid (GABA) using $^1H$ NMR spectroscopy from whole cell extracts of plant suspension cultures. When 9 cell lines derived from 8 species of higher plants maintained in liquid Marashige and Skoog (MS) medium supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) were subjected to $^1H$ NMR, a cell line of Coriandrum sativum L. exhibited the highest level of GABA. The level reached up to 16.9 mg/dry wt when cells were cultured in MS medium supplemented with 0.5 mg/L 2,4-D after 3 weeks of incubation. The method for quantitative determination of GABA using $^1H$ NMR established in this study could be applied to high-throughput screening of various plant resources for GABA production and the cell suspension culture system of C. sativum could be further developed for commercial production of GABA.

• Journal of Microbiology and Biotechnology
• /
• v.9 no.3
• /
• pp.282-291
• /
• 1999

Lactic acid bacteria were isolated from Kimchi and screened for bacteriocin. A total of 99 strains showed antimicrobial activity when grown on solid media, yet only 10 showed antimicrobial activity in liquid media. Strain H-559, identified as Lactococcus lactis subsp. lactis, exhibited the strongest inhibitory activity and was active against pathogenic bacteria including Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus as well as other lactic acid bacteria. The antimicrobial substance produced by L. lactis subsp. lactis H-559 was confirmed to be a bacteriocin by the treatment of $\alpha$-chymotrypsin, and protease type Ⅸ and ⅩIV. The bacteriocin activity remained stable between pH 2.0 and pH 11.0 and during heating for 10 min at $100^{\circ}C$. The bacteriocin production started in the exponential phase and stopped in the stationary phase. L. lactis subsp. lactis H-559 showed the highest bacteriocin activity at a culture temperature of $25^{\circ}C$, and an inverse relationship between the bacteriocin productivity and mean growth rate at different culture temperatures was observed. The mean growth rate and bacteriocin productivity of L. lactis subsp. lactis H-559 increased as the initial pH of the media increased.

• Journal of Mushroom
• /
• v.16 no.3
• /
• pp.162-170
• /
• 2018

To improve the productivity of Pleurotus ostreatus, different conditions of liquid spawn culture were tested. The optimum culture conditions were potato dextrose broth, incubation temperature of $22^{\circ}C$, and pH 6. Fifteen different media ('A' to 'O') containing 0.3% soybean meal (SM) were prepared by varying sugar and glucose contents. The cultures were propagated in SM media for 14 days, at $22^{\circ}C$, and pH 6. Their absorbances were higher after 14 days of incubation in the media containing both sugar and glucose. In particular, the absorbance of media containing 5 to 20% of glucose alone ('C', 'D', 'E', and 'F') tended to increase in the incubation period. Dry cell weight was lower in media containing less than 20% sugar or glucose alone than in media containing 30% sugar ('A') or 30% glucose ('B') alone. In sawdust media, in 900 mL-bottle, the optimum inoculation volume of liquid spawn was 15 to 20 mL. The texture of the mushroom cultivated with the liquid spawn was superior to that cultivated in the solid spawn.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2018.04a
• /
• pp.45-45
• /
• 2018

We had already reported the successful germination for green pods of purple lady's slipper orchid (Cypripedium macranthos Sw.). The green pod methods is to take immature seeds in green capsules, sterilize the capsule, and take out the sterile seeds. This method, however, needs very critical time of harvest. The critical time of seed harvest changes depending upon the species, condition of the specimen, and climatic influence, and the right time lies between 5 and 12 weeks after fertilization. In this study, the mature seeds were collected after 120-130 days with hand-polination of lady's slipper orchids. Mature seeds are usually dormant and it has to be overcome, either with hormone or storing the seeds near freezing for two or three months to break dormancy. The seeds were first surface sterilized with 70% ethanol and then transferred 1% NaOCl for 10-15 minutes, followed by rinses 3 times with sterilized distilled water. The cypripedium seeds consists of an embryo within a seed coat known as a testa. The testa is water repellent and the seed has a large air space between the embryo and testa so the seed tends to float on water. We had resolved the problems with vacuum pump to soak water into the testa before sterilization. The seeds were placed on liquid or agar solidified germination media. Cultures were incubated at $24{\pm}1^{\circ}C$ in dark. The seeds were germinated in 6-8 weeks in liquid suspension culture (germination percentage over 18%); however, the seeds on agar solidified media took more than 5 months to germinate and the germination percentage less than 5%. The most effective media for liquid culture was 1/4 strength Murashige and Skoog (MS) medium with 50 ml/l coconut water ($4brix^{\circ}$) at pH 5.8.

• The Korean Journal of Pharmacology
• /
• v.26 no.1
• /
• pp.1-6
• /
• 1990

We established an in vitro system of central serotonergic neurons by culturing dissociated rat embryonic (El4) brainstem cells to 14 days in vitro and monitored the serotonergic neuronal growth by measuring 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) contents in the cells with hish performance liquid chromatography with electrochemical detection (HPLC-EC). We studied also tile effects of various drugs on the contents of 5-HT and 5-HIAA, confirming in vivo reports. The 5-HT content (13 ng/mg protein) and 5-HT turnover rate (17 pmol/mg protein/h) at 14 days in vitro were in good agreement with those reported in the adult rat brain. The 5-HT content was more easily depleted with p-chlorophenylalanine, a tryptophan hydroxylase inhibitor than with NSD 1015 (3-hydroxybenzylhydrazine), an aromatic L-amino acid decarboxylase (AADC) inhibitor. Incubation of the cultures with tryptophan or 5-hydroxytryptophan increased the rate of serotonin formation implying that neither tryptophan hydroxylase nor AADC is saturated with its amino acid substrate in this in vitro system . The 5-HT content was depleted by reserpine. The 5-HT and 5-HIAA contents were increased and decreased, respectively, by monoamine oxidase inhibitors. All the above results indicate that the biochemical properties of the central serotonergic neurons in this culture system reflect reliably those of central serotonergic neurons in vivo. We suggest that measuring 5-HT and 5-HIAA contents in the primary cultured dissociated brainstem-cells with HPLC-EC is useful in the study of pharmacology as well as toxicolgy of the central serotonergic neurons.

• Journal of Life Science
• /
• v.13 no.3
• /
• pp.265-272
• /
• 2003

The effect of liquid cultures of Cordyceps militaris (LCM) on weight gain, food intakes, food efficiency ratios, serum and hepatic lipids, fecal lipids excretion, serum protein and enzyme activities, were investigated in adult female rats (30 weeks old). Sprague-Dawley rats were assigned to one normal and four hyperlipidemic diet groups, Hyperlipidemic diet groups (20% fat, 1% cholesterol) were divided into high fat diet (LCM free water), 10%, 20% or 30% LCM diet groups (10%, 20% or 30% LCM in water) according to the levels of LCM supplementation. After 35 days of experimental diet consumption, the body weight gains, hepatic weights, and food efficiency ratios of the rats fed hyperlipidemic diets were significantly increased compared with those of the rats fed normal diet. The concentrations of serum and hepatic triglycerides, hepatic total lipid, and atherogenic index of the rats fed 20% or 30% LCM diets were significantly lower than those of the rats fed the high fat diet. The concentration of serum HDL-cholesterol of the rats fed all LCM diets was significantly higher than those of the rats fed the high fat diet. The fecal excretion of triglyceride in the rats fed 20% or 30% LCM diets was significantly higher than those of the rats fed high fat diet. The concentrations of serum and hepatic total cholesterol, serum LDL-cholesterol, and HDL-cholesterol/total cholesterol ratio, fecal excretion of cholesterol, and the activities of serum glutamic pyruvic transaminase and alkaline phosphatase of the rats fed all LCM diets were similar to those of the rats fed high fat diet. No differences were noted in the weights of kidney and femur, the serum concentration of glucose, total protein and albumin, and the activities of glutamic oxaloacetic transaminase and ${\gamma}$ -glutamyltranspeptidase, among the rats on all the experimental diets. These results showed that the 20% or 30% LCM diets feeding decreased the serum and hepatic triglycerides, and the atherogenic index, and increased the serum HDL-cholesterol of the adult female rats.