• The Korean Journal of Ecology
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• v.28 no.4
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• pp.181-188
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• 2005

Methods used to study carbon sequestration by soil aggregates have often excluded the concentric spatial variability and other dynamic processes that contribute to resource accessibility and solute transport within aggregates. We investigated the spatial gradients of carbon (C) and nitrogen (N) from the exterior to interior layers within macroaggregates, $6.3\sim9.5$ mm, sampled from conventional tillage (CT) and no tillage (NT) sites of a Hoytville silt clay loam. Spatial gradients in C accumulation within macroaggregates were related to the differences in C dynamics by determining the sizes and the turnover rates of fast C and slow C pools in the concentric layers of aggregates. Aggregate exteriors contained more labile C and were characterized by greater C mineralization rates than their interiors in both management systems. In contrast, C in the interior layers of aggregates was more resistant in both systems. These results indicated the spatial differentiation of C dynamics within macroaggregates, i.e., exterior layers as a reactive site and interior layers as a protective site. Greater total C distribution in the exterior layers of NT aggregates indicated more influx of C from the macropores in interaggregate space than C. mineralization (net gain of C), whereas lower C distribution within the exterior layers of CT aggregates indicated net loss of C by greater C mineralization than C influx. We found total C increased approximately 1.6-fold by the conversion of CT soils to NT management systems for a period of 36 years. Differences in total accumulation and the spatial distribution of C within aggregates affected by management were attributed to the differences in aggregate stability and pore networks controlling the spatial heterogeneities of resource availability and microbial activity within aggregates.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.1
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• pp.8-12
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• 1998

Two experiments were conducted to determine the effects of $MnSO_4$ on controlling harmful microorganisms in vitro and in vivo. The in vitro experiment was conducted to examine the effects of manganese sulfate $(MnSO_4)$ on the reduction of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by growth stimulation of Pediococcus acidilactici (P. acidilactici; lactic acid bacteria). Manganese ion (0.003 %) was found to stimulate the growth of P. acidilactici in the In Vitro system. When E. coli and S. aureus were grown in a mixture with P. acidilactici, their numbers were reduced. This may be the result of a reduction of pH in the medium as a result of better growth of P. acidilactici due to stimulation by the Mn ion. The in vivo experiment was conducted to determine the effects of $MnSO_4$ in diets on controlling harmful microorganisms in fecal samples of pigs. There were no significant differences for the microbial numbers (i.e., total microorganisms, E. coli, lactic acid bacteria and S. aureus) in feces of pigs fed $MnSO_4$ compared to feces of pigs fed the control diet through 7 days. However, on day 7 of experiment, the pH of feces in pigs fed $MnSO_4$ (0.1%) decreased faster than pigs fed the control diet.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.642-647
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• 2012

Eight continuous culture fermenters were used in a completely randomized design to evaluate various nutritional values of Kochia (Kochia scoparia) compared with Atriplex (Atriplex dimorphostegia). Dried and pelleted samples (leaves and stems) provided substrate for metabolism by ruminal microbes maintained in a continuous culture fermentation system. Results indicated that there were no differences (p>0.05) in dry matter (DM) and crude protein (CP) digestibility between the two halophytic plants. Atriplex had higher (p<0.05) organic matter (OM) digestibility compared with Kochia. Neutral detergent fiber (aNDF) digestibility of Atriplex (411 g/kg) was higher (p<0.05) than that of Kochia (348 g/kg), however acid detergent fiber (ADF) digestibility was higher (p<0.05) in Kochia compared with Atriplex (406 vs. 234 g/kg). There were no differences (p>0.05) between the two halophytic plants in molar proportion of acetate and propionate, but the concentration of butyrate and valerate in Kochia were about two fold of Atriplex (p<0.05). When Kochia provided substrate to the microbes, protein synthesis was higher (p<0.05) compared with feeding Atriplex (5.96 vs. 4.85 g N/kg of OM truly digested). It was concluded that Kochia scoparia and Atriplex dimorphostegia had similar digestibility of DM and CP. It appears that these halophytic plants may not have enough digestible energy for high producing ruminants.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2012.05a
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• pp.8-8
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• 2012

Ginseng have been traditionally used for strengthening immunity, providing nutrition and recovering health from fatigue. Recently, pharmaceutical activities of ginseng roots have been proven by many researches, and ginseng has become a world-famous medicinal plant. Ginseng saponin, ginsenoside, is one of the most important secondary metabolite in ginseng which has various pharmacological activities. Many studies have aimed to convert major ginsenosides to the more active minor ginsenoside Rg3 for consumer demand ginseng product. Microbial strain GS514 strain was isolated from soil around ginseng roots for enzymatic preparation of ginsenoside Rg3, which strain shows strong ability of converting ginsenoside Rb1and Rd into Rg3 in the solution with NaCl. The gene encoding a ${\beta}$-glucosidase from this GS514 was cloned and expressed in the BL21 (DE3) strain of Escherichia coli. The recombinant enzyme was purified and characterized. The molecular mass of purified was 87.5 kDa, as determined by SDS-PAGE. The gene sequence revealed significant homology to the family 3 glycoside hydrolases. The purified single enzyme also catalyzed the conversion of ginsenoside Rb1 into Rg3. This target enzyme will be able to produce as much saponin for consumer demand ginseng product. Anti-apoptotic proteins bind with pro-apoptotic proteins to induce apoptosis mechanism. Over expression of these anti-apoptotic proteins lead to several cancers by preventing apoptosis. Docking simulations were performed for anti-apoptotic proteins with several ginsenosides from Panax ginseng. Our finding shows ginsenosides particularly Rg3, Rh2 and Rf have more binding affinity with apoptotic proteins. Further, these docking system of each ginsenosides can be extended to experimental screen system for further brief confirmations of several diseases.

• Journal of Animal Science and Technology
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• v.63 no.3
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• pp.563-574
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• 2021

A total of 1512 Ross 308 broilers (one - day - old) were assigned (random blocks) to 1of 3 dietary treatments with 28 replicates of 18 chicks/cage. The dietary treatments were Cornsoybean-meal based basal diet supplemented with 0%, 0.1%, and 0.2% of commercial yeast hydrolysate (YH [Saccharomyces cerevisiae]). The graded level of YH supplementation has linearly increased broilers body weight gain on d 21, 35, and overall (p = 0.044, 0.029, and 0.036, respectively) experimental period. In addition, the increased level of YH supplementation has linearly reduced feed conversation ratio of broilers on d 21, 35, and overall trial period (p = 0.041, 0.052, and 0.032, respectively). However, the feed intake and mortality of broilers were not affected by the graded level of YH supplementation. Though nutrient digestibility of dry matter (p = 0.012) and nitrogen (p = 0.021) was linearly increased in broilers fed YH supplementation, at the end of the trial it fails to affect the total track digestible energy. Dietary inclusion of YH supplementation showed a beneficial effect on the microbial population as linearly improved lactobacillus (p = 0.011) and reduced Escherichia coli counts (p = 0.042). An increasing level of YH supplementation has tended to decrease NH₃ (p = 0.069) and linearly decrease H₂S (p = 0.027) of noxious gas emission in broilers. Moreover, dietary YH supplements trend to increase the glucose (p = 0.066) and reduced cholesterol (p = 0.069) level. At the end of the test, YH supplementation elicited a linear reduction in drip loss on days 5 and 7, respectively (p = 0.045, and 0.021). Furthermore, dietary inclusion of YH supplementation had linearly increased villus height (p = 0.051) but fails to affect crypt depth. Therefore, in terms of positive effects on the broiler's overall performance, we suggest that dietary supplements containing graded YH levels in the broilers diet could serve as a potential alternative for growth promoters.

• Food Science of Animal Resources
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• v.41 no.1
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• pp.122-134
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• 2021

Recently, yogurt has been extensively studied to further enhance its functions using edible plant extracts. This study was conducted to investigate whether safflower petal (SP) as a natural food additive can be used to develop functional yogurt with improved health benefits. SPs were extracted with ethanol (SPE) and hot water (SPW), and then safflower yogurt was prepared by adding 0%-1.0% of those extracts to plain yogurt. With an increase in the fermentation duration, the pH of SPE and SPW yogurt samples was decreased, whereas titratable acidity and microbial counts were increased. The concentration of total polyphenols and total flavonoids, the activity of antioxidants, and the inhibitory effect on reactive oxygen species (ROS) were higher in SPW yogurt than SPE yogurt. Furthermore, α-glucosidase and lipase activity inhibitory effects of SPW yogurt were higher than those of SPE yogurt. In particular, free radical-scavenging activities, ROS inhibitory effect, and α-glucosidase activity inhibitory effects were significantly increased in SPW yogurt in a dose-dependent manner. Overall, these results suggest that SP extract possesses antioxidant activities and that it can downregulate α-glucosidase and lipase activities. The SP extract may have potential benefits as a natural food additive for the development of functional yogurt.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.1
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• pp.57-65
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• 2017

In a column experiment with low rank coal, rice straw was additionally supplied to induce methane gas generation by microorganisms in the state of supplying microorganisms and nutrients, and long-term biogas production characteristics were observed. When the weight ratio of the rice straw to coal was 0.04 or less, there was no significant gas generation. At 0.08, the biogas was generated for about 90 days. However, the methane gas generation was only 5% compared with the vial test result at optimum condition. Therefore, in order to produce biogas in the coal deposit in situ, a reactor that operates at COD concentration of 2000 mg/L or more at a ratio of 1:3 or more of rice straw to coal should be installed on the ground or under the ground. Liquid from the column filled with coal and rice straw and a liquid from vial containing rice straw were analyzed by microbial community analysis using pyrosequencing method, and compared the dominant microbial species among the two samples. In terms of the uniformity and diversity of the bacteria, the coal-filled column showed various species distribution, which has shown to be a disadvantageous microbial distribution to methane production.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.185-185
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• 2007

Starting at the beginning q the 20th century, increasing amounts of tetrach1oroethene (PCE) and trichloroethene (TCE)were manufactured due to the extensive use of these compounds in industry, in the military, and in private households, mainly as nonflammable solvents. This widespread use, along with careless handling and storage, are among the most serious contaminants of soil, sediment and groundwater. Highly chlorinated ethenes are typically not degraded through oxygenation by aerobic bacteria Since complete reductive dechlorination of PCE and TCE to ethene (ETH) has been observed in anaerobic enrichment culture, anaerobic dehalorespiring bacteria have received increased attention in the last decade. Under anaerobic conditions, these compounds con be reductively dehalogenated to less-chlorinated ethenes or innocuous ethene by microorganism through dehalorespiration. We have been studying anaerobic enrichment culture which used lactate as the electron donor for reductive dechlorination of PCE to ETH the anaerobic mixed microbial culture was enriched from the sediment sample taken from site contaminated with PCE. PCE was consistently and completely converted to ethene. In addition, the accumulation of intermediate products such as 1,2-ds-dichloroethene (cis-DCE) and vinyl chloride (VC) was observed in the anaerobic mixed microbial culture. the established dechlorinating enrichment culture was analyzed by DGGE using primers specific to DefrJ1ococcoides 16S rRNA gene sequences. In conclusion, we established the PCE dechlorinating enrichment culture and confirmed the existence of Dehalococcoides in an enrichment culture.

• The Korean Journal of Mycology
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• v.31 no.1
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• pp.44-49
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• 2003

Several microbial biocontrol products (Greenbiotech Co., Paju, Korea), Green-all T (Trichoderma harzianum), Green-all S(Bacillus sp.) and Green-all G (Streptomyces sp.) were supplemented with organic amendments such as sawdusts and rice hulls to study on efficacy of biological control of seeding damping-off of cucumber caused by Pythium ultimum. Sawdusts amended into potato dextrose agar alone could inhibit in vitro mycelial growth of P. ultimum. All there microbial products of Green-all T, Green-all G and Green-all S significantly reduced seeding damping-off (LSD, P=0.05). However, several amendments such as sawdusts and rice hulls into Green-all T and Green-all S products did not increase efficacy of biological control compared to non-amended treatment. In contrast, supplements of aminodoctor containing several amino acids (Greenbiotech Co., Korea) into Green-all G product significantly increased efficacy of biological control of seeding damping-off, resulting in from 42% to 2% disease incidence in relation to seedling emergence (LSD, P=0.05). Also, amendment of sawdusts into Tricoderma product significantly increased efficacy of biological control as disease index of 5.0 compared to non-amended control of 56.0 in Green-all T product alone. This indicates that organic amendments could increase efficacy of biological control of cucumber seedling damping-off.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.748-763
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• 2003

Anaerobic rumen microorganisms mainly bacteria, protozoa and fungi degrade ligno-cellulosic feeds consumed by the ruminants. The ruminants in developing countries are predominantly maintained on low grade roughage and grazing on degraded range land resulting in their poor nutrient utilization and productivity. Hence, manipulation of rumen fermentation was tried during last two decades to optimize ruminal fermentation for improving nutrient utilization and productivity of the animals. Modification of rumen microbial composition and their activity was attempted by using chemical additives those selectively effect rumen microbes, introduction of naturally occurring or genetically modified foreign microbes into the rumen and genetically manipulation of existing microbes in the rumen ecosystem. Accordingly, rumen protozoa were eliminated by defaunation for reducing ruminal methane production and increasing protein outflow in the intestine, resulting in improve growth and feed conversion efficiency of the animals. Further, Interspecies trans-inoculation of rumen microbes was also successfully used for annulment of dietary toxic factor. Additionally, probiotics of bacterial and yeast origin have been used in animal feeding to stabilize rumen fermentation, reduced incidence of diarrhoea and thus improving growth and feed conversion efficiency of young stalk. It is envisaged that genetic manipulation of rumen microorganisms has enormous research potential in developing countries. In view of feed resource availability more emphasis has to be given for manipulating rumen fermentation to increase cellulolytic activity for efficient utilization of low grade roughage.