• Food Science and Biotechnology
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• v.17 no.2
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• pp.442-445
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• 2008

Meju, a major ingredient of doenjang which is a popular Korean traditional fermented soyfood, was manufactured by fermenting steamed soybeans in natural environment in which steamed soy was exposed to airborne microorganism, in particular, fungi. Total isoflavone content was reduced from 1,849 mg/kg of cooked soy to 816 mg/kg of meju at the $90^{th}$ day of fermentation. Total glycosides and aglycones of isoflavones in meju were 1,827 and 22 mg/kg at 0 day and changed into 487 and 329 mg/kg at the 90th day of fermentation, respectively. Meanwhile, the ratio of glycosides to aglycones of isoflavones was not changed during aging of doenjang but remained relatively constant with 592 and 644 mg/kg aglycones at the 0 and $160^{th}$ day, respectively. When cooked soy was fermented with Aspergillus oryzae and Aspergillus flavus, isoflavone profiles were significantly different from each other while A. oryzae caused more extensive metabolism of isoflavones than A. flavus.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.810-817
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• 2011

A feeding trial was conducted to study the effect of tannin rich Pakar (Ficus infectoria) leaves on microbial profile, rumen fermentation and nutrient utilization in goats. Eight goats divided in two groups were fed pakar leaves (experimental group) and green oats (control group) as sole roughage source along with a fixed quantity of concentrate mixture for a period of 3 months. Two metabolic trials of six days duration were conducted after 30 and 90 days of experimental feeding. The dry matter intake was significantly higher (p<0.05) and digestibility's of DM, OM, CP, EE, NDF and ADF were reduced in experimental as compared with the control group. The TDN intake was similar (236.52 vs. 240.39 g/d) in both the groups. All the animals were in positive nitrogen balance. The concentration of ammonia nitrogen, TVFA, lactic acid and activities of xylanase and protease were reduced in pakar leaves fed goats. The rumen microbial profile as obtained by MPN technique showed no change in total bacterial population but total fungi and cellulolytic bacteria were reduced (p<0.05), whereas, tannin degrading/tolerant bacteria increased with the feeding of pakar leaves. Real time PCR data revealed a decrease in Ruminococcus flavefaciens, an increase in methanogens and no change in the Fibrobacter succinogenes population by feeding of pakar leaves.

• Journal of Environmental Health Sciences
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• v.42 no.2
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• pp.133-140
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• 2016

Objectives: A pilot study was undertaken to assess the bioaerosol levels in restaurants and determine the effects of variations in temperature, relative humidity, and air movement on these levels. It focused on the differences between kitchens and dining areas, as well as between summer and winter. Methods: A field survey was performed in six restaurants. An Anderson type air sampler was used for sampling bioaerosols, such as total suspended bacteria (TSB), Gram-negative bacteria (GNB), Gram positive bacteria (GPB), opportunistic bacteria (OP), Staphylococcus spp., and total suspended fungi (TSF). Results: The average levels of TSB were $1{\times}10^2CFU/m^3$ and of TSF they were $1{\times}10^0{\sim}10^1CFU/m^3$. The kitchens had higher bioaerosol levels compared to dining areas, and summer showed much higher levels than winter. The concentration of OP in summer was more than six-fold that of winter. S. aureus was detected both in kitchens and dining areas, even in winter. The main effect of air movement on TSB levels was significant (p<0.05), as was air temperature, relative humidity and air movement on TSF levels (p<0.05). Conclusion: There was a wide variation in bioaerosol levels among different restaurants. The results indicate that cooking foods may be a key factor affecting bioaerosol levels. The effects of air temperature and relative humidity reveal that bioaerosol levels may vary according to the season. The observation of pathogenic bacteria suggests that the hygiene management of establishments should be improved. Future research is needed to characterize the relation between bioaerosol levels and the occupant density of the dining area.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.11
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• pp.1583-1591
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• 2013

The objective of this study was to investigate microbial population in the rumen of dairy steers as influenced by supplementing with dietary condensed tannins and saponins and different roughage to concentrate ratios. Four, rumen fistulated dairy steers (Bos indicus) were used in a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design. The main factors were two roughage to concentrate ratios (R:C, 60:40 and 40:60) and two supplementations of rain tree pod meal (RPM) (0 and 60 g/kg of total DM intake). Chopped 30 g/kg urea treated rice straw was used as a roughage source. All animals received feed according to respective R:C ratios at 25 g/kg body weight. The RPM contained crude tannins and saponins at 84 and 143 g/kg of DM, respectively. It was found that ruminal pH decreased while ruminal temperature increased by a higher concentrate ratio (R:C 40:60) (p<0.05). In contrast, total bacterial, Ruminococus albus and viable proteolytic bacteria were not affected by dietary supplementation. Numbers of fungi, cellulolytic bacteria, Fibrobactor succinogenes and Ruminococus flavefaciens were higher while amylolytic bacteria was lower when steers were fed at 400 g/kg of concentrate. The population of Fibrobactor succinogenes, was found to be higher with RPM supplementation. In addition, the use of real-time PCR technique indicated that the population of protozoa and methanogens were decreased (p<0.05) with supplementation of RPM and with an increasing concentrate ratio. Supplementation of RPM and feeding different concentrate ratios resulted in changing the rumen microbes especially, when the animals were fed at 600 g/kg of concentrate and supplemented with RPM which significantly reduced the protozoa and methanogens population.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.206-211
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• 2001

This experiment was conducted to investigate the effects of mixed culture with mycotoxigenic and non-mycotoxigenic fungi on mycotoxin production. For this work, Aspegillus flavus (aflatoxin producing strain), Aspegillus niger (non-mycotoxigenic strain) and Penicillium griseofulvum (patulin producing strain)were cultured in 5 ml SLS medium for 15 days under single or mixed culture. Aflatoxin was determined by direct competitive ELISA, whereas, patulin was measured by HPLC. The mycelial growth, pH and total acidity were also observed by general methods. The mycelial growth was slightly decreased in the mixed culture, meanwhile total acidity was increased and pH was shown lower than that in single culture. Aspergillus flavus produced 145 $\mu\textrm{g}$/ml of aflatoxin for 12 days single culture, but in mixed culture, aflatoxin was decreased to 93%, and was shown as 10.16$\mu\textrm{g}$/ml level. Patulin production in mixed culture was also decreased to 69.3% and was shown only 23.72$\mu\textrm{g}$/ml level as compared with in single culture.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.1
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• pp.73-81
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• 1991

To assess biological air quality, concentrations of viable airborne microbes were determined in hospital home and outdoor air from August 25 to October 18, 1990. Bacteria, fungi and thermophilic bacteria were sampled using gravitational and suctional sampling method. In bacteria groups, the Staphylococcus spp. was identified by microscopic examination and biochemical tests. Results of the study are as follows. 1. Results using the gravitational sampling method indicated that average numbers of airborne microbes in hospital home and outdoor air were 21.5, 12.2 and 17.6 CFU/plate, respectively. These levels are well within an appropriate standard of 50 CFU/plate suggested by Endo. 2. Results using the suctional sampling method indicated that total airborne microbe concentrations in hospital, home and outdoor air were 1,998, 1,363 and $1,880CFU/m^3$, respectively. All of the results were within the recommended remedial action level, $10,000CFU/m^3$ of the American Conference of Governmental Industrial Hygienists(ACGIH). 3. Concentration of thermophilic bacteria in hospital and outdoor air were 79 and $111CFU/m^3$, respectively. Thermophilic bacteria were not detected in the home air. These results were within the remedial action level, $500CFU/m^3$. 4. Concentrations of Gram negative bacilli in holpital home and outdoor air were 20.3, 23.6 and $16.8CFU/m^3$, respectively. all were within the remedial action level, $500CFU/m^3$, recommended by ACGIH. 5. Concentrations of Staphylococcus spp. in hospital, home and outdoor air were 34.8, 14.7, and $22.4CFU/m^3$. respectively. all were within the remedial action level, $75CFU/m^3$, recommended by ACGIH. The percentages of Staphylococcus spp. in total bacteria in hospital, home and outdoor air were 19.0, 10.2 and 14.5%, respectively.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1347-1356
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• 2013

Tricholoma matsutake, an ectomycorrhiza that has mutual relationships with the rootlet of Pinus denisflora, forms a fruiting body that serves as a valuable food in Asia. However, the artificial culture of this fungus has not been successful. Soil fungi, including T. matsutake, coexist with many other microorganisms and plants; therefore, complex microbial communities have an influence on the fruiting body formation of T. matsutake. Here, we report on the structures of fungal communities associated with the fairy ring of T. matsutake through the pyrosequencing method. Soil samples were collected inside the fairy ring zone, in the fairy ring zone, and outside the fairy ring zone. A total of 37,125 sequencing reads were obtained and 728 to 1,962 operational taxonomic units (OTUs) were observed in the sampling zones. The fairy ring zone had the lowest OTUs and the lowest fungal diversity of all sampling zones. The number of OTUs and fungal taxa inside and outside the fairy ring zone was, respectively, about 2 times and 1.5 times higher than the fairy ring. Taxonomic analysis showed that each sampling zone has different fungal communities. In particular, out of 209 genera total, 6 genera in the fairy ring zone, such as Hemimycena, were uniquely present and 31 genera, such as Mycena, Boletopsis, and Repetophragma, were specifically absent. The results of metagenomic analysis based on the pyrosequencing indicate a decrease of fungal communities in the fairy ring zone and changes of fungal communities depending on the fairy ring growth of T. matsutake.

• Journal of Environmental Health Sciences
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• v.40 no.4
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• pp.304-312
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• 2014

Objectives: This study was performed to examine bioaerosols in indoor air in public restrooms, as well as to assess the effects of air temperature and relative humidity on bioaerosol levels. Methods: A cross-sectional survey was performed in ten male and ten female restrooms. An air sampler (Anderson type) was used for sampling total suspended bacteria (TSB), Gram-negative bacteria (GNB), Gram-positive bacteria (GPB), opportunistic bacteria (OP), Staphylococcus spp., and total suspended fungi (TSF). Results: The levels of TSB were $10-10^2CFU/m^3$ and TSF $10-10^2CFU/m^3$, respectively. The GNB level was $0-10CFU/m^3$, and GPB and OP levels were $10-10^2CFU/m^3$. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) were detected in 90% of the restrooms. The GPB level was higher in the female restrooms than in the male restrooms (p < 0.05). TSB, GNB, and TSF showed higher levels in restrooms in buildings over 30 years old (p < 0.01). The main effect of air temperature or relative humidity and interaction effect of the two factors on the TSB level were significant (p < 0.05), while the effect of relative humidity on the TSF level was significant (p < 0.001). Conclusions: These results indicate that there is a wide variation in the bioaerosol levels among different restrooms. The observed differences in bioaerosol levels reflect different building histories. The effects of air temperature and/or relative humidity reveal that bioaerosol levels may vary according to season or time of day. Future research is needed to further characterize the relation between the bioaerosol levels and surface contamination in restrooms.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.363-368
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• 2007

Traditional kochujang samples were collected from the folk village in Sunchang to find the major microbial composition and correlation between the taste and the microbial properties. Among the 29 samples, 17 samples showed Bacillus licheniformis as dominant strain with 11 samples Bacillus subtilis and 1 sample Staphylococcus pasteuri. Subdominant strain of 17 samples was Bacillus licheniformis with 12 samples Bacillus subtilis. Dominant strain numbers varied in rage of $6.60{\sim}8.38$ logCFU/g with subdominant strain number $5.90{\sim}7.86$ logCFU/g and total microbial number $6.64{\sim}8.56$ logCFU/g respectively. Bacterial type number varied in range of $6{\sim}18$ with the average 10.5 types. Fungi were found only in 2 samples and identified all to be Aspergillus oryzae. Yeasts were found in 25 samples. The dominant yeast strain of 23 samples was identified to be Zygosaccharomyces pseudorouxii and that of 2 samples Zygosaccharomyces rouxii. Yeast type variety showed that only single type was found in 15 samples, 2 types in 8 samples, 3 types in 1 sample and 4 types in 1 sample. Fungal number was 3.90 and 4.08 logCFU/g and yeast numbers varied in range of $3.90{\sim}6.43$ logCFU/g. The sensory scores of kochujang showed positive correlation with type numbers, but no significant correlation with the other microbial properties like total bacterial number, dominant bacterial number, subdominant bacterial number and dominant yeast number.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.918-921
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• 2000

A comparative study on rumen bacterial and protozoal population and fungal zoospores in cattle (Brahman$\times$Native) and swamp buffalo (Bubalus bubalis) was conducted. Forty animals, twenty of each, with same sex and similar age which were raised under similar condition in the Northeast of Thailand, were used. Rumen digesta were sampled immediately post slaughtering for total microscopic counts of bacteria, protozoa and fungal zoospores. It was found that total bacterial population were higher in swamp buffalo that those in cattle (1.6 vs $1.36{\times}10^{8}cells/ml$) having more population of cocci, rods and ovals. Lower rumen protozoal pupulation in swamp buffalo with lower numbers of Holotrichs and Entodiniomorphs were found as compared to those in cattle. Significant higher fungal zoospore counts were in swamp buffalo than those in cattle being 7.30 and $3.78{\times}10^6$, respectively. Study under electron microscope, revealed Anaeromyces sp. with acuminate apex were more predominant in the rumen of swamp buffalo. With these findings, cattle and swamp buffaloes showing differences in rumen bacterial, protozoal population and fungal zoospore counts, offer new additional information as why swamp buffaloes exhibit conditionally better than cattle especially during long dry season without green grass.