• Journal of Animal Science and Technology
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• v.49 no.5
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• pp.647-656
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• 2007

In order to investigate the effects of supplemental ionic surfactants in in vitro ruminal fermentation, N-Lauroylsarcosine sodium salt(N-LSS) and sodium dodecyl sulfate(SDS) for negative(－) ionic surfactant, and hexadecylpyridinium chloride monohydrate(HPCM) and hexadecyltrimethyl ammonium bromide(HTAB) for positive (+) ionic surfactant were supplemented by 0.05% and 0.1% into the Dehority’s artificial medium containing rice straw(1mm) as a substrate. In vitro DM digestibility, the growth of rumen mixed microbes, pH, cumulative gas production and SEM(Scanning Electron Microscopy) observation of microbial attachment on rice straw particle were investigated through the experiment composing 9 treatments (two supplemental levels of two positive ionic(+) surfactant, two supplemental levels of two negative(－) ionic surfactant) including the control. The sample collection was at 6, 12, 24, 48 and 72 h post fermentation with 3 replications per treatments. DM digestibility in treatments supplemented (+) or (－) surfactants almost stopped afterward 12 h fermentation, in vitro DM digestibility at 72 h post fermentation in the ionic surfactants was at half level of that of the control(P<0.05). Accumulative gas production in in vitro was less(P<0.05) with addition of ionic surfactants compared to the control. The amount of rumen mixed microbes recovered from in vitro incubation fluid pleateaued at 12 h post fermentation for the positive (+) ionic surfactants, but steadily increased as fermentation time elapsed for the control. Rumen microbial growth rate was significantly(P<0.05) low in the negative(－) ionic surfactant compared to the control. pH of the incubation fluid was ranged from 6.02 to 7.20, and was the highest in the negative(－) ionic surfactants, and was the lowest in the control(P<0.05). In SEM observation, rumen microbial population attached on rice straw particle was less with addition of ionic surfactants than the control. In conclusion we could not found any positive effects of negative- and positive- charged surfactants on rumunal fermentation characteristics and rumen microbial growth rates.

• Journal of Life Science
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• v.18 no.4
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• pp.515-521
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• 2008

This experiment was conducted to investigate effects of non-ionic or zwitterionic (+/-) surfactants on digestibility of rice straw, and changes of growth of rumen mixed microbes, pH, and gas production during in vitro fermentation. Also, during in vitro ruminal fermentation, microbial attachment on rice straw was investigated using scanning electron microscopy (SEM). Tween 80 or SOLFA-850 for non-ionic surfactant (NIS), and 3-(Dodecyldimethylammonio) propanesulfanate (DDAP) for zwitterionic surfactant (ZIS) was supplemented by 0.05% and 0.1% in Dehority's artificial medium containing Holtein rumen fluid, respectively, and the substrate for fermentation was rice straw passed through 1 mm screen. The experiment was composed of 7 treatments (two levels of two NISs, two levels of a ZIS) including the control, and 6, 12, 24, 48 and 72 hr of fermentation time with 3 replications per treatment. Treatment of Tween 80 increased in vitro DM digestibilities during 48 hr and 72 h post fermentations compared to the other treatments, whereas treatment of DDAP as a ZIS resulted in decreased DM digestibility than that of the control from 24 hr post fermentation (P<0.05). Gas production in vitro was greater (P<0.05) with addition of NIS than the control or ZIS, and increased as fermentation time elapsed. Rumen mixed microbial growth was greatest with addition of Tween 80 as NIS, and lowest when DDAP as ZIS was supplemented to the fermentation tube (P<0.05). In SEM observation, rumen microbial population attached on rice straw particle was greater with addition of NIS, but was less with addition ZIS compared with the control. In conclusion we could not found any positive effects of ZIS surfactants on rumunal fermentation characteristics and rumen microbial growth rates.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.227-235
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• 2019

This study monitored Daecheong 1-bo, Daecheong-stream, which carried out the project in 2014, from 2015 to 2016. The technology applied to the stream was evaluated using Periphytic Algae to check contamination indicators and ecological health of the area with an integral river-bed protection using non-toxic materials. The water quality of the monitoring section was confirmed to be above the river environment standard (II), and it was confirmed that the Saproxenic taxa of the river bed protection were higher than the upper and downstream sections. The TDI, which is an index of attachment algae, was shown in the average 51.03 and 52.15 for the pilot project sections in 2015 and 2016, confirming that the index is of the "normal" grade. This is the other sections in the upstream and downstream sections showed higher than "bad", which is thought to have a positive effect on the habitat of the river ecosystem components, especially the microbial population in river bed protection.

• Journal of Periodontal and Implant Science
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• v.51 no.1
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• pp.53-62
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• 2021

Purpose: This study aimed to evaluate the clinical and microbiological efficacy of adjunctive local delivery of minocycline (Periocline^®) in patients receiving supportive periodontal therapy (SPT) after initial treatment. Methods: The participants were 16 men and 8 women (age, 20-65 years) who had at least 15 natural teeth, underwent SPT for more than 1 year due to chronic periodontitis, had 4 or more periodontal pocket sites deeper than 5 mm, and showed >25% gingival bleeding on probing (BoP). They were randomly assigned to the test and control groups. In the test group, mechanical debridement and local antibiotic delivery were performed for all periodontal sulci/pockets; in the control group, mechanical debridement and saline irrigation were performed. In patients who underwent SPT for more than 1 year, clinical and microbiological examinations were performed at baseline and 1 and 3 months after SPT. The clinical examination included an assessment of the periodontal pocket depth, clinical attachment level, plaque index, and BoP. Microbial tests were performed using real-time polymerase chain reaction; the relative ratios of Porphyromonas gingivalis and Fusobacterium nucleatum were determined. Results: Both groups showed significant improvements in clinical parameters at 1 and 3 months from baseline; there were no significant changes between months 1 and 3. Intergroup differences were insignificant. The microbiological analysis revealed no significant differences in P. gingivalis and F. nucleatum ratios across time points. While intergroup differences were insignificant, there was a tendency for the P. gingivalis and F. nucleatum ratios to decrease in the test group. Conclusions: Mechanical debridement in patients receiving maintenance therapy resulted in clinically significant improvement; the effectiveness of additional local delivery of antibiotics was not significant. The ratios of P. gingivalis and F. nucleatum showed a tendency to decrease in the test group, although it was not significant.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.10
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• pp.561-567
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• 2017

This study focused on estimating the low concentration of $NH_4{^+}-N$ removal by using simultaneous reaction of the adsorption and microbial nitrification with microbe-attached zeolite media. To evaluate the adsorption effect of the zeolite media, the expanded polypropylene (EPP) media which are not able to adsorb $NH_4{^+}-N$ were used as a control media in order to compare the adsorption ability. Each media was used to experiment after aerated 8 hr for attachment of the microbes. The batch experiment shows that nitrification occurred in zeolite media better than EPP media because nitrifiers could consume the relatively enough amount of $NH_4{^+}-N$ adsorbed onto the zeolite media. Compared to the reactor with EPP media, nitrification occurred only in the reactor with zeolite media under continuous operation at the empty bed contact time (EBCT) of 25 min and 3 mg/L of $NH_4{^+}-N$ concentration. As the EBCT of the reactor with zeolite media increased from 10 to 60 min, the nitrification efficiencies increased too. $NH_4{^+}-N$ removal efficiency showed up more than 90% at EBCT 60 min. And the difference in concentration of the total nitrogen between the influent and the effluent was 0.25 mg/L at EBCT 10 min, 0.78 mg/L at EBCT 25 min, 0.59 mg/L at EBCT 40 min and 0.37 mg/L at EBCT 60 min, respectively. This difference was due to between adsorption rate and nitrification rate of $NH_4{^+}-N$, and it was considered that $NH_4{^+}-N$ was adsorbed on the zeolite media by the gap of the concentration.

• Journal of Animal Environmental Science
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• v.13 no.1
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• pp.13-20
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• 2007

Sawdust biofiltration is an emerging bio-technology for control of ammonia emissions including compost odors from composting of biological wastes. Although sawdust is widely used as a medium for bulking agent in composting system and for microbial attachment in biofiltration systems, the performance of agitated bed composting and sawdust biofiltration are not well established. A pilot-scale composting of hog manure amended with sawdust and sawdust biofiltration systems for practical operation were investigated using aerated and agitated rectangular reactor with compost turner and sawdust biofilter operated under controlled conditions, each with a working capacity of approximately $40m^3\;and\;4.5m^3$ respectively. These were used to investigate the effect of compost temperature, seed germination rate and the C/N ratio of the compost on ammonia emissions, compost maturity and sawdust biofiltration performance. Temperature profiles showed that the material in three runs had been reached to temperature of 55 to $65^{\circ}C$ and above. The ammonia concentration in the exhaust gas of the sawdust biofilter media was below the maximum average value as 45 ppm. Seed germination rate levels of final compost was maintained from 70 to 93% and EC values of the finished compost varied between 2.8 and 4.8 ds/m, providing adequate conditions for plant growth.