Activation of Macrophages by Exopolysaccharide Produced by MK1 Bacterial Strain Isolated from Neungee Mushroom, Sarcodon aspratus

BACKGROUND: The MK1 strain, a novel bacterial isolate from soft-rotten tissue of the Neungee mushroom, produces copious amounts of exopolysaccharide (EPS) in a dextrose minimal medium. This study examined the molecular characteristics and immunomodulatory activity of MK1 EPS. METHODS: The EPS in the culture supernatant was purified by cold ethanol precipitation, and characterized by SDS-PAGE/silver staining and Bio-HPLC. The immunomodulatory activities of the EPS were examined using the mouse monocytic cell line, RAW 264.7 cells. RESULTS: The molecular weights of the purified EPS were rather heterogeneous, ranging from 10.6 to 55 kDa. The EPS was composed of glucose, rhamnose, mannose, galactose, and glucosamine at an approximate molar ratio of 1.00:0.8:0.71:0.29:0.21. EPS activated the RAW cells to produce cytokines, such as TNF-alpha and IL-1beta, and nitric oxide (NO). EPS also induced the expression of co-stimulatory molecules, such as B7-1, B7-2 and ICAM-1, and increased the phagocytic activity. The macrophage-activating activity of EPS was not due to endotoxin contamination because the treatment of EPS with polymyin B did not reduce the macrophage-activating activity. CONCLUSION: The EPS produced from the MK1 strain exerts macrophage-activating activity.

Ergosterol and Water Changes in Tricholoma matsutake Soil Colony during the Mushroom Fruiting Season

The purpose of this study is to understand spatio-temporal changes of active fungal biomass and water in Tricholoma matsutake soil colonies during the mushroom fruiting season. The active fungal biomass was estimated by analyzing ergosterol content at four different points within four replicated locations in a single circular T. matsutake colony at Ssanggok valley in the Sogri Mt. National Park in Korea during 2003 to 2005. The four points were the ahead of the colony, the front edge of the colony and 20 cm and 40 cm back from the front edge of the colony. Ergosterol content was 0.0 to 0.7 microg per gram dried soil at the ahead, 2.5 to 4.8 microg at the front edge, 0.5 to 1.8 microg at the 20 cm back and 0.3 to 0.8 microg at the 40 cm back. The ergosterol content was very high at the front edge where the T. matsutake hyphae were most active. However, ergosterol content did not significantly change during the fruiting season, September to October. Soil water contents were lower at the front edge and 20 cm back from the front edge of the colony than at the ahead and 40 cm back during the fruiting season. Soil water content ranged from 12 to 19% at the ahead, 10 to 11% at the edge, 9 to 11% at the 20 cm back and 11 to 15% at the 40 cm back. Our results suggest that the active front edge of the T. matsutake soil colony could be managed in terms of water relation and T. matsutake ectomycorrhizal root development.

Effect of Chitosan Acetate on Bacteria Occurring on Neungee Mushrooms, Sarcodon aspratus

Minimal growth inhibitory concentrations (MICs) of chitosan acetate (M.W. 60 kDa) on heterotrophic bacteria (strains MK1, S, and R) isolated from the soft-rotten tissues of Neungee mushroom (Sarcodon aspratus) were measured. The slimy substance produced by the MK1 strain was responsible for the diseased mushroom's appearance. The S and R strains were members of the Burkholderia cepacia complex. These strains showed different levels of susceptibility toward chitosan acetate. The MIC of chitosan acetate against the MK1 and S strains was 0.06%. The MIC against the R strain was greater than 0.10%. Survival fractions of the MK1 and S strains at the MIC were 3 x 10(-4) and 1.4 x 10(-3) after 24 h, and 2 x 10(-4) and 7 x 10(-4) after 48 h, respectively. Survival fractions of the R strain after 24 and 48 hr at 0.1% chitosan acetate were 1 x 10-2 and 6.9 x 10(-3), respectively. Compared to the MK1 and S strains, the low susceptibility of the R stain towards chitosan acetate could be due to the ability of the R strain to utilize chitosan as a carbon source. Thirty-eight percent of Neungee pieces treated in a 0.06% chitosan acetate solution for 2~3 second did not show any bacterial growth at 4 days, whereas bacterial growth around untreated mushroom pieces occurred within 2 days. These data suggest that chitosan acetate is highly effective in controlling growth of indigenous microorganisms on Neungee. The scanning electron micrographs of the MK1 strain treated with chitosan revealed a higher degree of disintegrated and distorted cellular structures.

Antibacterial Activity of Water Soluble Components of Elfvingia applanata Alone and in Combinations with Quinolones

A preparation of water soluble components(EA) was made from carpophores of Elfvingia applanata(Pers.) Karst and its in vitro antibacterial activity on a number of bacterial species was examined by macrobroth dilution assay. Among 16 species of bacteria tested, the most potent antibacterial activity was observed against Staphylococcus epiderrnidis and Proteus vulgaris, of which MICs were 1.25 mg/ml. To investigate the antibacterial effects in combinations of EA with quinolone antibiotics, such as ciprofloxacin, enoxacin, lomefloxacin, norfloxacin, and ofloxacin, the fractional inhibitory concentrations(FICs) and the fractional inhibitory concentration indices(FICIs) for four bacterial strains were determined by macrobroth dilution checkerboard assay. Combinations of EA and quinolones exhibited either additive or indifferent effects of antibacterial activity in most instances. However, both synergistic and antagonistic effects were not observed in any cases.

Antibacterial Activity of Water Soluble Components of Elfvingia applanata Alone and in Combinations with Third Generation Cephalosporins

Antibacterial activity of EA, a preparation of water soluble components made from carpophores of Elfvingia applanata (Pers.) Karst, was examined by macrobroth diltution method against a number of bacterial species. Antibacterial effects of EA were expressed as minimal inhibitory concentration (MIC) for growth. Among twelve species of bacteria tested, six strains of each gram positive bacteria and gram negative bacteria, EA showed the most potent antibacterial activity against Staphylococcus epidermidis and Proteus vulgaris, of which MICs were 1.25 mg/ml of EA. To investigate the antibacterial effects of combinations of EA with third generation cepholosporins, such as cefotaxime, ceftriaxone, ceftazidime, and cefixime, the fractional inhibitory concentration (FIC) and fractional inhibitory concentration index (FICI) were determined by macrodilution checkerboard assay for twelve bacterial strains. Combinations of EA and third generation cephalosporins exhibited either additive or indifferent effects in most instances. However, synergistic effects were observed in six instances. No antagonistic effect was observed in any cases.

Evaluation of Food Behavior of Secondary School Students in Seoul and Kyunggi Area

The purpose of this study was to find the proper methods of school food service conducted from June 20th July 30th in 1996. The subjects of this study were 587 parents of students, 794 students and 359 school teachers at 508 middle and high schools in Seoul and Kyunggi area. And the result was as follow. A total of 48.3% of respondent answered they had breakfast regularly. The reasons why they had breakfast, were habits(34.4%) followed by hunger(28.2%), health(19.9%), parent's persuasion(17.5%). They reasons why they didn't have breakfast are, lacks of time(68.8%) followed by absence of appetite(20.5%), diet(4.5%). About the question the problem of eating habits the most of parents of students, chose an unbalanced diet(25.9%), followed by overeating of snacks(21.7%), voracious eating(18.0%), not eating meals(17.5%), eating little(10%) and overeating(6.8%). At the research of an unbalanced diet, the 63.3% of respondents said they eat evenly while the 36.7% said they had an unbalanced diet. From the research of correlativity between food service at elementary schools and eating habits, we knew that the experience of school food service had an effect on an unbalanced diet. And the students living in Seoul complained more than in Kyunggi. The question about the quality of food, 69.0% of respondents said they were not so bad. While 21.2% said not delicious at all just 9.8% of students said they were very satisfied with the taste. Interestingly, more middle school students both in Kyunggi and Seoul answered the food was delicious than high school students. About the question of the price, 49.5% of students thought appropriate(49.5%) while 44.3% said it was too high. Just 5.9% students answered cheap(5.9%). And students living in Kyunggi thought the price was high than students in Seoul. 62.9% of respondents think their refectories were clean while 22.8% think not clean. And 14.3% answered said dirty. Snack bars at school were managed by the contract with trusters(63.2%), while by the school itself(32.6%).

The Changes and Suggestions in Korean Dietary Guideline / 대한지역사회영양학회지

The Recommended Dietary Allowances(RDAs, Nutrient standards), dietary guidelines, and food guides, each define aspects for a healthy diet in different ways. The RDA and food guide for Koreans were first established in 1962 by the Food and Nutrition Committee of the Korea FAO Association. The committee released the RDA and suggested ways to intake the recommended nutrients. Every five years, the committee has added more data and released revisions. The latest edition of the RDA is the 6th revision. In the beginning, the concept of basic food groups was emphasized as basic data for planning means based on RDA. In the 5th revision, the basic food groups and dietary guideline for public health from the Ministry of Health and Welfairs(December, 1990) suggests that, 1) Eat a variety of foods with a recommended fat intake equaling or less than 20% of total calories ; 2) Maintain ideal body weight and prevent obesity ; 3) Eat foods low in salt. Salt intake should not exceed 10g ; 4) Do not drink too much ; 5) Eat regularly and enjoy meals. After these guidelines were established, the first nutritonal education efforts guidelines were developed in 1984. Despite broad possibilities for application, they had limited use, mainly as a nutritional assessment and food balance sheet preparation. They were not well utilized in public nutritional education and nutritonal policy through the media because of the weakness of the government's food and nutriton policy. Also a lack of administrative support and dietitians in the health department and administrative organizations was partly to blame. In regard to public health and nutrition status, life expectancy has increased 10 years since the 70's and the elderly population increased threefold in 1995 compared to 1960. The common causes of death in 1996 by 19 Chapters classification, were first disease of the circulatory system ; the second, neoplasms ; the third, external causes fo mortality ; the forth, diseases of the digestive system ; and the fifth, respiratory system diseases, In food intake, grain and complex starch intake has decreased while fruit and animal foods have considerably increased. Therefore, energy from carbohydrates has decreased while energy from protein and fat has increased. Energy intakes from protein, fat and carbohydrates were respectively 12.5, 7.2 and 80.3% in 1969 but 16.1, 19.1 and 64.8% in 1995. 62.9% of the householes had the fat energy less than 20%, while 37.1% had the fat energy above 20%. The only intakes of vitamin A and calcium were below RDA levles. Therefore, nationwide attention should be focused on public nutriton education and public activities with supplementation of the RDAs, according to the food guide and the dietary guideline.

A Measurement of Rubella Antibodies among Korean Children by Enzyme-linked Immunosorbent Assay

We measured the degree of immunity of 326 Korean children to rubella virus by enzyme-linked immunosorbent assy (ELISA). They were admitted to Pediatrics Unit of Yonsei Medical Center between April and July, 1980 with various illnesses excluding rubella disease. Among the 326 tested, 172 cases gave a positive titer of antibodies (mainly, IgG and IgM antibodies) and 127 had IgG antibody against rubella virus antigen. These represented 52.8% and 39.0%, respectively, of the total number of children tested. There was no significant difference in the rate of positivity between sex, but the positive rate increased as the age increased. The antobody titers of positive individuals to rubella virus were higher among the older children. Results and a brief outline of the ELISA method for serodiagnosis of rubella in clinical use will be discussed.

Serratia marcescens sepsicemia; Nosocomial outbreak

An outbreak of nosocomial infections caused by Serratia marcescens is described. There were 40 bacterial isolates from 21 patients during a 3 month period at pediatric ward and sick baby room. Bacterial cultures from blood revealed positive in 19 patients out of 21, but one from urine and the other from bronchial secretions. 16 cases among 19 Serratia septicemia were completely recovered, but 3 patients were discharged without adequate treatment. We lost two patients in spite of vigorous medical treatment. Factors associated with Serratia infections were previous multiple and ?road-spectrum antimicrobial therapy and underlying chronic debilitating disese. Indwelling intravenous catheter and previously instrumented urinary tract were the most frequent portals of entry. The isolated strains were resisant to most antibiotics, but most frequently sensitvive to gentamicin, amikacin and chloramphenicoI. It is recommended that until specific antibiotic sensitivities can be obtained, patients with Serratia septicemia should be treated with chloramphenciol in combination with gentamicin or amikacin. Dust collection of the sick baby room, the incubators of the pediatric ward and the nurse room were contaminated with serratia marcescens. The distilled water of the cold steam and incubator were also contaminated. The culture of the specimens from the hands of doctors and nurses revealed many Serratia organisms. The control measures were instituted and the outbreak stopped. These data demonstrate that the organism can become pathogenic for man in certain clinical situations, especially in patients with chronic debilitating disease who have been treated with multiple antibiotics. These experience emphasized the problems in recognition of hospital associated infections.

Studies on Exocellular Substances of Mycobacterium ulcerans. I. Prelimiary Report on a Susceptible Animal to the Substances

This is a report on attempts tp search for a suitable experimental animal model which is sensitive to the exocellular substances of M. ulcerans, prior to study of biochemical and pathogenic natures of the substances. Cells of M. ulcerans grown in a broth medium were harvested by filtration and washed with phosphate-buffered saline. The filtrate of culture supernatant was subjected to fractionation by addition of various amounts of ammonium sulfate. The washed cells and the preparations resulted from ammonium sulfate fractionation (ASF 45 and ASF 70) were inoculated by either foot-pad injection, subcutaneous or intradermal injection to the selected animal groups. Any skin response due to administration of the preparations; erythema, edema, pus formation, etc. was macroscopically observed along with time progression. Among the animals employed, such as guinea pig, mouse, and rabbit, the rabbit was the only animal group showing strong skin response to the washed cells, ASF 45 and ASF 70. The heat-treated preparation of ASF 45 seemed to be inactive in elucidating skin response of rabbits. Dependence of skin response upon dose of the washed cells and the preparation of ASF 45 was also discussed.

Comparison of Mycobacterial Growth in Dubos Medium, Hyaluronate Supplemented Medium and Umbilical Cord Extract Based Medium

This is a report of attempts to compare the growth yields of various species of fastidious mycobacterium inch1ding human pathogens and non-pathogens in the conventional Dubos liquid medium and two simple media formulated recently; one is a medium containing 0.1% hyaluronic acid and 6.0% bovine serum albumin and the other is a semisyntheic medium made of umbilical cord extract supplemented with 10% sheep serum as a final concentration. All mycobacterial strains employed in experiments gave the heaviest growth yields in the hyaluronic acid-bovine serum albumin medium (HAS medium), among the three media. Dubos liquid medium seemed to be inferior to a medium made of umbilical cord extract (UCE medium) in supporting mycobacterial growth. There were three-to seven-fold increases in dry weight of the bacteria grown in the HAS medium as compared with those in the Dubos liquid medium. We also looked for the possible effect of bovine serum albumin (BSA)in the HAS medium on mycobacterial growth. As a result, we found that the amount of BSA in the HAS medium, ranging from zero to 6.0% in the medium, showed no substantial effect on the mycobacteria1 growth.