• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.468-476
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• 2021

This study examined the effects of a hydrothermal pretreatment (HP) on the nutritional values and in vitro fermentation characteristics of tall fescue and corn silage. This study was conducted through a factorial design of 2 (control or HP) × 2 (hay; tall fescue or silage; corn). For the HP, forage was placed into a glass bottle with 20% w/v of water, and the glass bottle was sealed and heated to reach a temperature of 121℃ (0.12 MPa). The solid residue and liquid were collected and oven-dried at 65℃ for three days. The dried materials were tested for in vitro fermentation at 39℃ for 24 and 48 h. The content of ADF increased significantly regardless of the forage type. After in vitro incubation for 24 h, the total VFA content was significantly lower after HP, regardless of the forage type (p ≤ 0.05), and the propionate concentration was increased in corn silage with HP (p ≤ 0.05). After 48 hours of in vitro incubation, the propionate content increased significantly (p ≤ 0.03) in corn silage with HP (p ≤ 0.05), but the butyrate content decreased significantly (p ≤ 0.05). There was no change in the in vitro dry matter and neutral detergent fiber digestibility by HP regardless of the forage type. Therefore, the use of hydrothermally pretreated corn silage could be advantageous for the supply of energy for ruminants.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.410-416
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• 2010

Methane emitted from ruminant livestock is regarded as a loss of feed energy and also a contributor to global warming. Methane is synthesized in the rumen as one of the hydrogen sink products that are unavoidable for efficient succession of anaerobic microbial fermentation. Various attempts have been made to reduce methane emission, mainly through rumen microbial manipulation, by the use of agents including chemicals, antibiotics and natural products such as oils, fatty acids and plant extracts. A newer approach is the development of vaccines against methanogenic bacteria. While ionophore antibiotics have been widely used due to their efficacy and affordable prices, the use of alternative natural materials is becoming more attractive due to health concerns regarding antibiotics. An important feature of a natural material that constitutes a possible alternative methane inhibitor is that the material does not reduce feed intake or digestibility but does enhance propionate that is the major hydrogen sink alternative to methane. Some implications of these approaches, as well as an introduction to antibiotic-alternative natural materials and novel approaches, are provided.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.974-978
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• 2001

The effect of three varying ratios (high, medium and low) of Rumen Degradable Protein (RDP) to Undegradable Dietary Protein (UDP) of 37:63, 52:48 and 70:30 in iso-nitrogenous and iso-caloric concentrate mixtures on rumen fermentation profile was studied using rumen fistulated Jersey crossbred cows. Rumen pH and ammonia nitrogen concentration were found to be lower with a concentrate mixture containing a higher UDP level of 63.38% when compared with those having medium and low UDP levels of 47.55 and 29.75%, respectively, at all post feeding intervals. Total volatile fatty acid concentration as well as concentrations of individual fatty acids viz., acetate, propionate and butyrate were also found higher in animals fed concentrate mixture with the highest UDP level.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.771-774
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• 2001

NADPH has been known as a regulating factor the biosynthesis of polyhydroxyalkanote(PHA), and the flux of NADPH for PHA biosynthesis could be enforced by the amplification of zwf gene encoding glucose 6-phosphate dehydrogenase. The recombinant plasmid pCZWF harboring PHA synthase, phbC from R. eutropha and zwf from E. coli were constructed, and were transformed to R. eutropha by electroporation. The biosynthesis of P(3HB-3HV) copolymer were carried out in transformant R. eutropha through the two-stage cultivation method using valerate as a precursor. The biosynthesis rate and PHA content of transformant R. eutropha harboring pCZWF were increased compared with transformant R. eutropha harboring only phbC. Especially, the molar fraction of 3HV was increased from 68% to 74% due to amplification of zwf gene. And the biosynthesis P(3HB-3HV) and P(3HB-4HB) carried out using propionate and ${\gamma}-butyrolactone$ as a precursor, respectively. But the rate, content, and molar fraction of biosynthesis copolymers were not influenced appreciably. This may be due to the reduced availability of NADPH.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.209-213
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• 2003

Self-assembled monolayers of spinach ferredoxin immobilized to Au substrate were investigated. Ferredoxin was immobilized onto the chemically modified Au surface. Au surface were modified to $NH^{3+}$ by the 4-aminothiphenol and then modified by N-succinimidyl-3-[2-pyridyldithio]propionate for the ferredoxin immobilization. To verify the electrochemical activity of immobilized ferredoxin molecules, cyclic-voltammetry was measured. Finally, to verify the memory application, reduction potential was applied to ferredoxin molecules as for the write function, and then current transients observed from the reduced ferredoxin layers were measured for the read function of memory applications.

• Natural Product Sciences
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• v.16 no.4
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• pp.211-216
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• 2010

A new 3-indolyl propionate alkaloid; (-) abrine (1), was isolated from the alcohol extract of Erythrina caffra stem bark together with the alkaloid (-) hypaphorine (2). Phytochemical investigation of the chloroform extract led to the isolation of one fatty alcohol; 1-octacosanol, isolated for the first time from genus Erythrina, two dienoid alkaloids; erythraline and erysodine, and three isoflavonoids; 3S (+) 2'-O-methylphaseollidinisoflavan (3), (6aR, 11aR)- 3-hydroxy-10-dimethylallyl-9-methoxypterocarpan, known as sandwicensin (4) and 3R (-) rythbidin A (5). It is worth mentioning that this is the first report for the isolation of these isoflavonoids from E. caffra. The absolute configuration of 3S (+) 2'-O-methylphaseollidinisoflavan (3) was not previously reported. The isolated isoflavonoids showed promising antibacterial activity against Staphylococcus aureus.

• Journal of Photoscience
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• v.7 no.2
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• pp.59-61
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• 2000

As a potential electroluminescent material, tetrahydrochrysene (THC) is prepared using the dehydrocyclization following the acyloin condensation of methyl-3-phenyl propionate as key step from trans-mehyl cinnamate in 3 steps. THC showed emission at 428 and 456 nm after the photo- and electro-excitation, respectively. The luminance of THC doped on PVK was about /$25 cdm^2$ at 30 voltage with 70 nm of thickness. The results suggests that a new fluorescent organic dye, THC can be used organic electroluminescent device.

• Journal of Microbiology and Biotechnology
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• v.2 no.4
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• pp.268-272
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• 1992

Alcohol dehydrogenase activity of Clostridium acetobutylicum ATCC 4259 was studied for its specificity against substrates in acidogenic and solventogenic cultures. The bacterium reduces propionate, valerate and caproate added to the medium to the corresponding alcohols. Acetaldehyde, propionaldehyde, butyraldhyde, pentanal, and hexanal were used as the substrates by alcohol dehydrogenase, and all were reduced to the corresponding alcohols with varying affinities and reaction velocities. Acetaldehyde showed the lowest affinity and lowest velocity while the other aldehydes showed similar $K_m\;and\;V_max$ values. NADPH was used as the electron donor for the reduction of aldehydes. Alcohol dehydrogenase activity was low in acidogenic culture, and high in solventogenic culture.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.94-99
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• 1991

- The further study for the identification of the previously reported pink-pigmented facultative methylotrophic bacterium (PPFM) GL-10 was carried out. The PPFM GL-10 was Gram nagative, rod, and motile by a single polarly inserted flagellum. The colonies were smooth, pink, circular, along with convex with entire margin. The isolate could utilize C1 compounds and a variety of multicarbon substrates as sole carbon and energy source. The isolate was obligately aerobic, and exhibited both catalase and oxidase activities. The deoxyribonucleic acid base composition was 65-67 mol% guanine plus cytosine. The isolate was mostly identical with Methylobacterium extorquens and named Methylobacterium sp. strain GL-10. Methylobacterium GL-10 accumulated a copolyester of 3-hydroxybutyrate and 3-hydroxyvalerate (poly-3HB/3 HV) when grown in nitrogen-free culture media containing sodium propionate as substrate at the second polyester accumulation stage. The composition of copolyester, as determined from $^1h$ NMR spectra, was 23 mol% of 3-hydroxyvalerate (3HV).

• Journal of the Korean Society of Tobacco Science
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• v.21 no.1
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• pp.49-56
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• 1999

Classification of esterase isozymes of the apterous green peach aphids (Myzus persicae Sulzer) collected in tobacco fields were investigated by the native polyacrylamide gel electrophoresis (PAGE). A total of twelve esterase bands were identified in adult apterous aphid, and the difference of enzyme band activity in the clones was observed at the first and second bands group. Esterases of green peach aphids reacted with specific substrate were more stained $\alpha$-naphthyl acetate than $\alpha$-naphthyl propionate, and $\alpha$-naphthyl acetate more than $\beta$-naphthyl acetate. Twelve esterases on the basis of inhibition by the three types of inhibitors (organophosphates: 2.5$\times$10$^{-3}$ M paraoxon, 4$\times$10$^{-3}$ M DFP; eserine sulfate : 2$\times$10$^{-3}$ M eserin; sulfhydryl reagents: 2$\times$10$^{-3}$ M p-HMB) were classified into three class, namely, cholinesterase (ChE) I, II, carboxylesterase (CE) and arylesterase (ArE), and these classes contained 3, 4, 3 and 2 isozymes, respectively.