• Korean Journal of Microbiology
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• v.48 no.2
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• pp.125-133
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• 2012

Anaerobic digestion is an alternative method to digest food wastes and to produce methane that can be used as a renewable energy source. We investigated bacterial and archaeal community structures in a three-stage methane production process using food wastes with concomitant wastewater treatment. The three-stage methane process is composed of semianaerobic hydrolysis/acidogenic, anaerobic acidogenic, and strictly anaerobic methane production steps in which food wastes are converted methane and carbon dioxide. The microbial diversity was determined by the nucleotide sequences of 16S rRNA gene library and quantitative real-time PCR. The major eubacterial population of the three-stage methane process was belonging to VFA-oxidizing bacteria. The archaeal community consisted mainly of two species of hydrogenotrophic methanogen (Methanoculleus). Family Picrophilaceae (Order Thermoplasmatales) was also observed as a minor population. The predominance of hydrogenotrophic methanogen suggests that the main degradation pathway of this process is different from the classical methane production systems that have the pathway based on acetogenesis. The domination of hydrogenotrophic methanogen (Methanoculleus) may be caused by mesophilic digestion, neutral pH, high concentration of ammonia, short HRT, and interaction with VFA-oxidizing bacteria (Tepidanaerobacter etc.).

• KSBB Journal
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• v.21 no.6 s.101
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• pp.451-455
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• 2006

An efficient pilot scale (10 ton) three-stage methane fermentation system to digest food waste has been developed in this laboratory. This system consisted of three stages: semianaerobic hydrolysis, anaerobic acidogenesis and strictly anaerobic methanogenesis. From the secondary acidogenesis reactor, a novel strain KA4 responsible for alcohol fermentation was isolated and characterized. The cell was oval and its dimension was $5.5-6.5{\times}3.5-4.5\;{\mu}m$. This strain was identified as Saccharomyces cerevisiae KA4 by 26S rDNA D1/D2 rDNA sequence. Optimal culture temperature was $30-35^{\circ}C$. Cells were tolerant to 5% (v/v) ethanol concentration, however, were inhibited significantly by higher ethanol concentration up to 7%. The strain could grow well up to 50% (w/v) initial glucose concentration in the YM liquid medium, however, optimal concentration for ethanol fermentation was 10%. It could produce ethanol in a broad initial pH range from 4 to 10, and optimal pH was 6. In this condition, the strain converted 10% glucose to 7.4% ethanol during 24 hr, and ethanol yield was estimated to be 2.87 moi EtOH/mol glucose.

• Journal of Mushroom
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• v.3 no.2
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• pp.52-59
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• 2005

The Aphyllophorales is a large order containing about 2,000 known species. Many of these are the bracket and coral fungi. The vast majority of these fungi are saprophytic on the plant debris. Many species are significant in decomposing plant remains, as they are able to digest cellulose or lignin that occurs in plant cell walls. Many of these fungi have been involved in everyday human affairs. A few were used medicinally by the Greeks and Romans as a remedy for many complaints, including colic, fractured limbs and bruises. Other bracket fungi have been used as curry combs for horses, as snuff, as razor strops and as a source of dye for clothing. The texture of the basidiocarp may be similar to that of cork, wood, leather, paper, or cartilage. Unlike the basidiocarps of the Order Agaricales, the basidiocarps of the Aphyllophorales are not fleshly and moist. Division of the members of the Aphyllophorales into genera was originally made on the basis of gross morphology of the basidiocarp and hymenium and Donk(1964) recognizes 22 families in this order. The species and genus whose typical in Aphylloporales were listed in Table. with related information. The ITS region sequence of some genus were found by BLAST search. Sequences retrieved from GenBank were visually aligned by the program CLUSTAL G. As a result, the medicinal mushroom was separated in four groups. In this multiple alignment, the sequence analysis among Fomes group, Inonotus group and Phellinus group showed high genetic similarity except Hericium group and Sparassis group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.921-925
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• 2003

To control blood glucose level as close to normal is the major goal of treatment of diabetes mellitus. $\alpha$-glucosidase is the enzyme to digest dietary carbohydrate and inhibition of $\alpha$-glucosidase could suppress postprandial hyperglycemia. The methanol extract of soybean sprout was tested for the inhibitory activities against $\alpha$-glucosidase in vitro. Soybean sprout extract inhibited yeast $\alpha$-glucosidase activity by 24.5% at the concentration of 5 mg/mL. The methanol extract of soybean sprout was subsequently subjected to sequential fractionation with hexane, ethyl acetate, butanol and water. Among the fractions tested ethyl acetate-soluble fraction showed relatively strong inhibition against $\alpha$-glucosidase by 36.3% at the concentration of 5 mg/mL. Acarbose, standard $\alpha$-glucosidase inhibitor, inhibited $\alpha$-glucosidase activity by 40.1%. The ability of soybean sprout extract to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. Starch solution (1 g/kg) with and without the methanol extract of soybean sprout (500 mg/kg) was administered to diabetic rats after an overnight-fast by gastric intubation. A single oral dose of soybean sprout extract inhibited the increase in blood glucose levels significantly at 60, 90, 120, 180 min (p<0.05) and decreased incremental response areas under the glycemic response curve significantly (p<0.05). These results suggest that soybean sprout might exert hypoglycemic effect by inhibiting $\alpha$-glucosidase activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.4
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• pp.312-319
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• 1988

The functional properties of plasteins have been compared with those of sardine protein concentrate and egg albumin. The solubility of plasteins was higher than that of FPG and the glu-plastein had 84% solubility in the range of pH 3-10. The dispersibility of plasteins was lower than that of egg albumin, however those of plasteins was higher than that of sardine protein concentrate. The water holding capacity of plasteins was higher than that of egg albumin. Lipid absorption of leu-papain plastein was the highest, holding 2.2m119, and that of the other plastein was higher than that of egg albumin. The emulsifying activity of leu-papain plastein was the highest, holding 66.4%, and that of glu-papain plastein was the lowest, holding 51.2%, The emulsifying stability of plasteins was similar to that of the emulsifying activity. The foaming capacitt of leu-papain plastein was the highest, holding 460%, and those of the other plasteins was higher than that of egg albumin. The foaming stability of plasteins was superior to that of egg albumin. The viscosity of plasteins was lower than that of see albumin. The in vitro digestibility of plasteins was 67.6-78.0% range. The digestibility by four pretense were somewhat lower in the glu-papain plastein than in the FPG. The digest of plasteins treated with the microbiol pretense such as molsin and pretense(from Streptomyces griceus), which had a storage broth taste.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.7
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• pp.998-1003
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• 2016

Although exogenous protease enzymes have been used in poultry diets quite extensively, this has not been the case for pig diets. In general, due to their better gut fermentative capacity and longer transit time, pigs have greater capacity to digest dietary proteins than poultry. However, in early-weaned piglets, the stress brought about by weaning adversely affects the digestion of dietary proteins. Therefore, a study was conducted to determine the effects of a commercial protease enzyme in weanling pigs. Indices of growth, nutrient digestibility, blood profiles, fecal microflora, fecal gas emission and fecal scores were measured during the study. A total of 50 weanling pigs ($6.42{\pm}0.12kg$) at 28 d of age were randomly assigned to receive 1 of 2 dietary treatments: i) control diet (corn-soy based) with no supplemental protease (CON), and ii) control diet+200 g/ton protease (PROT) for 42 d. A completely randomized design consisting of 2 treatments, 5 replicates, and 5 pigs in each replicate was used. Growth performance in terms of body weight ($27.04{\pm}0.38kg$ vs $25.75{\pm}0.39kg$; p<0.05) and average daily gain ($491{\pm}7.40g$ vs $460{\pm}7.46g$; p<0.05) in PROT fed pigs were increased significantly, but gain per feed ($0.700{\pm}0.01$ vs $0.678{\pm}0.01$; p>0.05) was similar between treatments at d 42. Relative to CON pigs, PROT fed pigs had increased (p<0.05) apparent total tract digestibility ($84.66%{\pm}0.65%$ vs $81.21%{\pm}1.13%$ dry matter and $84.02%{\pm}0.52%$ vs $80.47%{\pm}1.22%$ nitrogen) and decreased (p<0.05) $NH_3$ emission ($2.0{\pm}0.16ppm$ vs $1.2{\pm}0.12ppm$) in the feces at d 42. Except for a decreased (p<0.05) in blood creatinine level, no differences were observed in red blood cell, white blood cell, lymphocyte, urea nitrogen, and IgG concentrations between treatments. Fecal score and fecal microflora (Lactobacillus and E. coli) were also similar between CON and PROT groups. Overall, the supplementation of protease enzyme in weanling pigs resulted in improved growth rate and nutrient digestibility. Exogenous protease enzyme reduced fecal $NH_3$ emission, thus, potentially serving as a tool in lowering noxious gas contribution of livestock production in the environment.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1169-1180
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• 2005

First, I read all the materials, including Dongeuibogam(Encyclopedia Medica Koreana), classical writings on Lacca sinica exsiccata, herbal writings on lacquer poison, and herbal books on how to treat lacquer poison. And then after 1 examined all the details on qi and taste of Lacca sinica exsiccata, its efficacy, detoxification, lacquer poison, and its effects on body symptom, 1 got the following results. The order of frequency that Lacca sinica exsiccata is used in Dongeuibogam is pressure-feeling, blood circulation, and insect biting. Its way of intake is not so much through herb-boiling or powdered medicine as through hand-made pills. When medicine is used in the form of pills, the Lacca sinica exsiccata is more included among other ingredients. When old doctors treated pressure-feeling in the chest, they mixed up other herbs, with not putting more emphasis on the efficacy of lacquer 010 doctors believed that toxicity of Lacca sinica exsiccata is not having its own poison, but having biased dominance in the use of its qE and taste. The way or detoxification or Lacca sinica exsiccata is used in the order of crab-boiled water, egg, Xanthoxylum piperitum, Perilla frutescens, Astar tataricus, a weeping willow, iron-tempered water, and Allium toberosum. Special point in detoxificating lacquer poison is that they used medicines for well-ciruculating pulmonary stream, medicines for promoting to urinate or discharge by helping large colons to move, medicines for making the lacquer scar small, medicines for helping digest, and medicines for improving vessel function in the poisoned area. With the above results, the more profound study, based on the crab-boiled water and egg, is expected to go on to increase the effect on the one hand, and to make the new way of lessening or removing the toxicity of lacquer with more safe use on the other hand.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.4
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• pp.253-259
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• 1996

Ammonia microdiffusion method and colorimetric measurement are described for the nitrogen determination. The diffusion of ammonia could be successfully induced by using a microdiffusion cell. It is a simple and rapid technique, which is suitable for transforming the nitrogen in digests into $NH_4CI$ for the colorimetric N determination with ammonia color reagent. Above 99% of N recovery were obtained with microdiffusion up to 15 hours. The coloration method of collected $NH_4CI$ for the colorimetric N determination was also estabilshed with a scanning in U.V. spectrophotometer. Under the proposed coloration method (0.5 mL of sample digest, 4.0 mL of $H_2O$ and 0.5 mL of ammonia color reagent), a maximal absorbance was observed at 410 nm. The kinetic measurement of absorbance showed a high stability from 5 to 45 minutes after color development. Absorbance was directly proportional to the amount of $NH_4^+-N$ present. The microdiffusion-ammonia coloration method was successfully applied to the nitrogen determination in the forms of protein-N or total -N in plant tissue. Comparing with Kjeldahl distillation method, the values obtained with described method were slightly higher and more reliable.

• Food Science of Animal Resources
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• v.36 no.6
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• pp.779-786
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• 2016

This study aimed to evaluate the prevalence of Listeria monocytogenes on livestock farms in Korea and determine their serotypes and genetic correlations. Twenty-five livestock farms in Korea (central: 15, south west: 7, south east: 3) were visited 2-3 times, and 2,018 samples (feces: 677, soil: 680, silage: 647, sludge: 14) were collected. Samples were enriched in LEB (Listeria enrichment broth) and Fraser broth media, and then plated on Palcam agar. The isolates were identified by PCR and 16S rRNA gene sequencing. Then, the sero-types, presence of virulence genes (actA, inlA, inlB, plcB, and hlyA), and antibiotic resistance were determined. Genetic correlations among the isolates were evaluated by analyzing the restriction digest pattern with AscI. Of the 2,018 samples, only 3 (0.15%) soil samples (FI-1-FI-3) from 1 farm in the south east region were positive for L. monocytogenes. Based on biochemical tests and multiplex PCR, the serotype of the isolates were 4ab (FI-1 and FI-3) and 3a (FI-2), which are not common in foodborne L. monocytogenes. The 3a sero-type isolate was positive for all tested virulence genes, whereas the 4ab serotype isolates were only positive for hlyA, actA, and inlA. The isolates were resistant to all 12 tested antibiotics, especially FI-3. The genetic correlations among the isolates were 100% for those of the same serotype and 26.3% for those of different serotypes. These results indicate that the prevalence of L. monocytogenes on livestock farms in Korea is low; however, the isolates are pathogenic and antibiotic resistant.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.179-186
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• 1998

Dextransucrase hyper-producing Leuconostoc mesenteroides B-512FMCM and dextransucrase constitutive mutants B-742CB and B-1355C catalyzed the transfer of glucose from sucrose to other carbohydrates which were present or were added to the reaction digests. When the acceptor was a maltose, gentiobiose, lactose or raffinose, there was produced a series of oligosaccharide acceptor products or single product based on the kinds of enzymes and reaction conditions. To obtain the quantitative information about the yield and the distribution of acceptor products and dextran two experimental parameters were studied: a) the ratio of acceptor to sucrose and b) the amount of enzyme at constant carbohydrate concentration (100 mM). As the amount of enzyme increased, the synthesis of acceptor products (of maltose or gentiobiose) increased, and the formation of dextran decreased. As the ratio of acceptor to sucrose increased, the amount of dextran and the number of acceptor-products decreased and the amount of acceptor-products increased. When maltose or gentiobiose was an acceptor, the glucose from sucrose was transferred to the C-6 hydroxyl group of the nonreducing-end glucose residue of accepters to give a homologous series of isomaltosyl dextrins. In case of lactose or raffinose, there was produced only one acceptor product from B-512FMCM dextransucrase reaction. In the lactose acceptor reaction, the glucose from sucrose was transferred to the C-2 hydroxyl of the reducing end glucose residue of lactose. To get a series of oligosaccharides from lactose or raffinose acceptor reaction we used B-742CB dextransucrase or B-1355C alternansucrase with 500 mM sucrose in reaction digest.