• ALGAE
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• v.20 no.4
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• pp.369-377
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• 2005

Seashore joining with land and sea, which is typical habitat for marine macroalgae, is classified two types of shore as soft- and hard-bottom shore according to topographical (geological) and ecological features. We compared two of Ulva pertusa Kjellman from two contrasting habitats, sandy (soft-bottom, Haenam) and rocky shore (hard-bottom, Hadong) in terms of chlorophyll-a fluorescence and its parameters, and various photosynthetic pigment and nutrient content in the tissue of those. Both of habitats were different in the light environment such as light attenuation coefficient and even in nutrient concentration of ambient seawater. Electron transport rate (ETR) of Ulva from sandy shore was higher than from rocky shore. The range of photosynthetic pigment content in the tissue of U. pertusa was significantly much more in from sandy shore, and also nitrogen and phosphorus content were significantly higher except for carbon content. However, there were no significant differences in the ratio of among photosynthetic pigments, and N:P ratio was similar between each other, even though significantly different. Our result implied on the reason of why most of green tides in the worldwide concentrated and frequently occurred at sites with sandy, muddy and silty bottoms, being classified as soft-bottom shore.

• Parasites, Hosts and Diseases
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• v.53 no.3
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• pp.335-339
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• 2015

Cryptosporidium andersoni ATP-binding cassette (CaABC) is an important membrane protein involved in substrate transport across the membrane. In this research, the nucleotide binding domain (NBD) of CaABC gene was amplified by PCR, and the eukaryotic expression vector of pEGFP-C1-CaNBD was reconstructed. Then, the recombinant plasmid of pEGFP-C1-CaNBD was transformed into the mouse intestinal epithelial cells (IECs) to study the iron transportation function of CaABC. The results indicated that NBD region of CaABC gene can significantly elevate the transport efficiency of $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $HCO_3{^-}$ in IECs (P<0.05). The significance of this study is to find the ATPase inhibitors for NBD region of CaABC gene and to inhibit ATP binding and nutrient transport of CaABC transporter. Thus, C. andersoni will be killed by inhibition of nutrient uptake. This will open up a new way for treatment of cryptosporidiosis.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.237-244
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• 1989

A soluble intracellular protease from cells of Pseudomonas carboxydovorans, a carboxydobacterium, grown on nutrient broth was purified 68-fold in five steps to better than 95% homogeneity with a yield of 2.4% using azocasein as a substrate. The enzyme activity was not detected from cells grown on pyruvate, succinate, acetate, or CO as a sole source of carbon and energy. The molecular weight of the native enzyme was determined to be 53,000. Sodium dodecyl sulfate-gel electrophoresis revealed the purified enzyme a monomer. The enzyme was found to be a serine-type protease. The enzyme activity was inhibited completely by several divalent cations such as $Cd^{2+}, Cu^{2+}, Hg^{2+}$, and $Fe^{2+}$. The enzyme was also inhibited by EGTA, but was stimulated by iodoacetamide. The optimal pH and temperature for the enzyme reaction were found to be 8.0 and $50^{\circ}C$, respectively. The enzyme was inactive on CO dehydrogenase.

• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.569-586
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• 2017

We inoculated a spent mushroom substrate from Flammulina velutipes (SMSF) with a microbial additive and assessed the effects on chemical composition, ruminal fermentation parameters, and total-tract nutrient digestibility. In Exp. 1, three cannulated Hanwoo steers were used in an in situ trial to determine the degradation kinetics of dry matter (DM) and crude protein (CP). In Exp. 2, three Hanwoo steers were randomly assigned to experimental diets according to a $3{\times}3$ Latin square for a 3-week period (2 weeks for adaptation and 1 week for sample collection). Experimental diets included the control diet (3.75 kg/d formulated concentrate mixture + 1.25 kg/d rice straw), SMSF diet (3.19 kg/d formulated concentrate mixture + 1.25 kg/d rice straw + 0.56 kg/d SMSF), and inoculated SMSF (ISMSF) diet (3.19 kg/d formulated concentrate mixture + 1.25 kg/d rice straw + 0.56 kg/d ISMSF). The chemical composition of ISMSF did not differ from that of SMSF. Microbial additive inoculation decreased pH (P<0.05) and improved preservation for SMSF. The percentages of DM, neutral detergent fiber (NDF), and acid detergent fiber (ADF) in ISMSF were slightly lesser than those in SMSF. Ruminal fermentation characteristics and total-tract nutrient digestibility were not affected by diet. Overall, microbial additive inoculation improved preservation for SMSF and may allow improved digestion in the rumen; however, the total digestible nutrients (TDN) of SMSF and ISMSF diets were slightly lesser than the control diet. The ISMSF can be used as an alternative feedstuff to partially replace formulated concentrate feed.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.993-1004
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• 2009

Three experiments were conducted to determine the effects of non-ionic surfactant (NIS) supplementation on ruminal fermentation, nutrient digestibility and performance of beef steers fed high-roughage diets. The objective of experiment 1 was to investigate the effects of NIS supplementation on in vitro ruminal fermentation of cultures administered with corn and barley as grain substrate and rice straw and timothy hay as roughage substrate. The in vivo ruminal fermentation, nitrogen balance and digestibility of nutrients were also examined with steers fed a high-roughage diet in experiment 2. The aim of experiment 3 was to determine the responses to NIS of growing steers fed a high-roughage diet. In experiment 1, ammonia nitrogen concentration for NIS supplementation was higher (p<0.05) than for the control with all substrates. However, concentrations of total volatile fatty acid (VFA), acetate, butyrate and valerate of the incubated roughage substrates, rice straw and timothy hay, were higher (p<0.05) for NIS supplementation than for the control whereas VFA concentrations in the cultures of corn and barley were unaffected. These results indicated that effects of NIS on ruminal fermentation are diet dependent, specifically on roughage sources. In experiment 2, ruminal pH of steers supplemented with NIS was lower (p<0.05) than the control. Ruminal concentrations of ammonia nitrogen, acetate, total VFA and urinary concentrations of purine derivatives were increased (p<0.05) by NIS supplementation. In experiment 3, supplementation of NIS increased (p<0.05) intakes of total feed and corn silage, average daily gain, and feed efficiency of growing steers although they varied depending on supplementation level. Due to the roughage-specific feature of NIS effects, NIS appears to enhance ruminal fermentation of fibrous parts of feeds and, consequently, performance of steers fed a high-roughage diet.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.208-213
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• 2007

The objective of the experiment was to determine the optimum cultural [moisture levels (55, 60 and 70%), days of fermentation (7, 14 and 21), temperature (25 and $35^{\circ}C$) of incubation)] and nutritional parameters (urea addition (0 and 2%) and variable levels of single super phosphate (0.25 and 0.50% SSP)) for bio-processing of the mustard (Brassica campestris) straw (MS) under solid-state fermentation (SSF) system. The performance of SSF was assessed in terms of favorable changes in cell wall constituents, protein content and in vitro DM digestibility of the MS. Sorghum based inoculum (seed culture) of Ganoderma lucidum to treat the MS was prepared. The 50 g DM of MS taken in autoclavable polypropylene bags was mixed with a pre-calculated amount of water and the particular nutrient in the straw to attained the desired levels of water and nutrient concentration in the substrate. A significant progressive increase in biodegradation of DM (p<0.001), NDF (p<0.01) and ADF (p<0.05) was observed with increasing levels of moisture. Among the cell wall constituents the loss of ADF fraction was greatest compared to that of NDF. The loss of DM increased progressively as the fermentation proceeded and maximum DM losses occurred at 28 days after incubation. The protein content of the treated MS samples increased linearly up to the day $21^{th}$ of the incubation and thereafter declined at day $28^{th}$, whereas the improvement in in vitro DM digestibility were apparent only up to the day $14^{th}$ of the incubation under SSF and there after it declined. The acid detergent lignin (ADL) degradation was slower during the first 7 days of SSF and thereafter increased progressively and maximum ADL losses were observed at the day $28^{th}$ of the SSF. The biodegradation of DM and ADL was not affected by the variation in incubation temperature. Addition of urea was found to have inhibitory effect on fungal growth. The effect of both the levels (0.25 and 0.50) of SSP addition in the substrate, on DM, NDF, ADF, cellulose and ADL biodegradation was similar. Similarly, the protein content and the in vitro DM digestibility remain unaffected affected due to variable levels of the SSP inclusion in the substrate. From the results it may be concluded that the incubation of MS with 60 percent moisture for 21 days at $35^{\circ}C$ with 0.25 percent SSP was most suitable for MS treatment with Ganoderma lucidum. Maximum delignification, enrichment in the protein content and improvement in in vitro DM digestibility were achieved by adopting this protocol of bioprocessing of MS.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.642-650
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• 1999

Options available for utilization of animal wastes include sources of plant nutrients, feed ingredients for farm animals, substrate for methane generation, and substrate for microbial and insect protein synthesis. The wastes have the most economic value for use as animal feed. Performance of animals fed diets containing animal wastes is similar to that of animals fed conventional diets. Processing of animal wastes to be used as animal feed is necessary for destruction of pathogens, improvement of handling and storage characteristics, and maintenance or enhancement of palatability. Feeding of animal waste has not adversely affected the quality and taste of animal products. In the USA copper toxicity has been reported in sheep fed high-copper poultry litter, but this is not a serious problem with cattle. Potential pathogenic microorganisms in animal wastes are destroyed by processing such as heat treatment, ensiling and deep stacking. Incidents of botulism, caused by Clostridium botulinum, have been reported in cattle in some countries, and this problem was caused by the presence of poultry carcasses in litter. This problem has not occurred in the USA. With appropriate withdrawal, heavy metal, pesticide or medicinal drug accumulation in edible tissues of animals fed animal wastes is not a problem. Feeding of animal wastes is regulated by individual states in the USA. The practice is regulated in Canada, also. With good management, animal wastes can be used safely as animal feed.

• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.448-457
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• 2005

The conventional activated sludge processes were operated as a combined organic substrate removal and nitrification. So, it was necessary to provide with oxygen for both carbon and ammonia removal. But, in the BNR processes, nitrification is separated from carbon removal that causes fast ammonia oxidation and reduced oxygen demands. And most of the substrate is utilized by denitrification organisms and phosphorus accumulating organisms. with these appearances, mathematical model for BNR processes different from IWA ASM can be simplified and applied. In this study, it was performed that the existing equations as McKinney model, nitrification model published by U.S. EPA and oxygen demands from stoichiometry and the relationship between NUR and OUR were applied to full-scale BNR processes and the results were compared with the measured. and it is possible to make out the optimum design parameter from those equations.

• Journal of Ecology and Environment
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• v.33 no.4
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• pp.317-323
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• 2010

Nutrient availability is a critical component of agroecosystems, and is relevant to both above- and below- ground interactions. The principal objective of this study was to determine how the cessation of fertilization affects the communities of weeds and soil organisms in a corn/wheat field. Changes in dominant weed species, substrate-induced respiration, and the population density of nematodes and microarthropods were evaluated. Microbial substrate-induced respiration (SIR) and the population density of microarthropods decreased following the cessation of fertilization and were partly correlated with the aboveground weed biomass. The cessation of organic fertilizer application but continuing application of inorganic fertilizer reduced the population density of nematodes. In response to the cessation of fertilization, weed communities were dominated by species with little dependency on fertilization. Amaranthus retroflexus was identified as the most dominant species in the corn field; however, it was replaced by Digitaria ciliaris after the cessation of fertilization. In the wheat field, the cessation of fertilization led to a rapid reduction in the biomass of most weeds, except for Vicia angustifolia, supposedly as the result of symbiotic nitrogen fixation. Additionally, the fact that weed biomass was partially correlated with SIR or the population density of microarthropods may reflect a mutual feedback between soil organisms and weeds. The results indicate that the cessation of fertilization alters communities of weeds and soil organisms through changes in weed biomass and interactions with symbiotic microorganisms.

• Journal of Microbiology
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• v.33 no.4
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• pp.315-321
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• 1995

The relationship between morphological differentiation and production of trypsin-like protease (TLP_ in streptomycetes was studied. All the Streptomyces spp.In this study produced TLP just before the onset of aerial mycelium formation. Addition of TLP inhibitor, TLCK, to the top surface of colonies inhibited aerial mycelium formation as well as TLP inhibitor, TLCK, to the top surface of colonies inhibited aerial mycelium formation as well as TLP activity. Addition of 2% glucose to the Bennett agar medium repressed both the aerial mycelium formation and TLP production in S. abuvaviensis, S. coelicolor A3(2), S exfoliatus, S. microflavus, S. roseus, s. lavendulae, and S. rochei. However the addition of glucose did not affect S. limosus, S. felleus, S. griseus, S. phaechromogenes, and S. rimosus. The glucose repression on aerial mycelium formation and production of TLP was relieved by the addition of glucose anti-metabolite (methyl .alpha.-glucopyranoside). Therefore, it was concluded that TLP production is coordinately regulated with morphological differentiation and TLP activity is essential for morphological differentiation in streptomycetes. The proposed role of TLP is that TLP participates in the degradation of substrate mycelium protein for providing nutrient for aerial mycelial growth.