• Analytical Science and Technology
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• v.25 no.6
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• pp.402-409
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• 2012

Quantitative analytical condition for arsenic in plastic materials by the flow injection-hydride generation-inductively coupled plasma-atomic emission spectrometry was studied. The plastic samples were dissolved by wet-acid digestion method and microwave-acid digestion method. The reproducibility and accuracy in this method was verified using of certified reference materials(CRMs) CRM-EC680k and CRM-EC681k. The analyical results agrees with certified value within the range of uncertainty. The results of CRM-EC680k wer 4.1~4.3 mg/kg (certified value $4.1{\pm}0.5$ mg/kg), and the results of CRM-EC681k were 28.9~30.6 mg/kg (certified value $29.1{\pm}1.8$ mg/kg).

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.812-815
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• 2005

This study was conducted to see the influence of additives and fermentation periods on Mott grass silage (MGS) characteristics, its chemical composition and to compare the digestion kinetics of Mott grass (MG) and MGS in Nili buffaloes. Mott grass chopped with a locally manufactured chopper was ensiled using two additives, cane molasses and crushed corn grains each at 2, 4 and 6% of forage DM for 30 and 40 days in laboratory silos. The pH, lactic acid concentration, dry matter (DM), crude protein and fiber fractions of MGS were not affected by the type or level of additive and fermentation periods. The non-significant pH lactic acid concentration, and chemical composition of MGS indicated that the both molasses and crushed corn were utilized at similar rate for the growth of lactic acid bacteria and production of organic acids. The MG ensiled with molasses at 2% of fodder DM for 30 days was screened out for in situ digestion kinetics in Nili buffaloes. Ruminal DM and neutral detergent fiber (NDF) degradabilities of MGS were significantly (p<0.05) higher than that of MG. The DM and NDF rate of degradation, lag time and extent of degradation was nonsignificant between MGS and MG. The higher ruminal degradation of DM and NDF of MGS than MG was probably a reflection of fermentation of MG during ensilation that improved its degradability by improving the availability of easily degradable structural polysaccharides to ruminal microbial population. The results in the present study have indicated that MG ensiled with either 2% molasses or 2% crushed corn for 30 days has better nutritive value for buffalo.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.104-112
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• 1999

Since the anaerobic rumen fungi were discovered in the rumen of a sheep over two decades ago, they have been reported in a wide range of herbivores fud on high fibre diets. The extensive colonisation and degradation of fibrous plant tissues by the fungi suggest that they have a role in fibre digestion. All rumen fungi studied so far are fibrolytic. They produce a range of hydrolytic enzymes, which include the cellulases, hemicellulases, pectinases and phenolic acid esterases, to enable them to invade and degrade the lignocellulosic plant tissues. Although rumen fungi may not seem to be essential to general rumen function since they may be absent in animals fed on low fibre diets, they, nevertheless, could contribute to the digestion of high-fibre poor-quality forages.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.1
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• pp.137-145
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• 1994

Amino acid (AA) substituted diets had no influence on rumen levels of total volatile fatty acids (VFA), ammonia and ${\alpha}$-amino-N, but tended to increase molar proportions of isovalerate and counts of total viable AA utilizing and celluloytic bacteria in the rumen as compared with the control urea diet. The AA diets did not affect daily flow to the duodenum of dry matter (DM), organic mater (OM) and acid detergent fibre (ADF), and rumen digestibility of these nutrients. However, the AA diets, in particular the 10 essential AA (EAA) diet improved total digestibility of DM, OM and ADF by decreasing faecal output of these fractions. Although N flow to the duodenum and N retention were not affected with the dietary treatments, duodenal bacterial flow appeared to increase by the AA diets when it was estimated by means of 2,6-diaminopimelic acid (DAP) and nucleic acid-purine bases (PB) as markers. The results suggest that AA supplements to a urea diet could improve feed utilization by stimulating microbial activity and proliferation in the rumen but and increased microbial activity per se is not necessarily associated with improvement of feed conversion.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.95-99
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• 1995

Acid phosphatase(AP) of he aphid, Megoura crassicauda and the major component of the lady beetle's artificial diet, fresh chicken liver, was adapted as a model protein to study the digestion of diet proteins in the midgut of Harmonia axyridis. The lady beetle did not secrete its own AP into the lumen of the midgut. The aphid and the live chicken liver had AP which was still alive in enzymatic activity from the extract of the lumen of the midgut of the lady beetle. The digestive ability of the lady beetle on proteins turned out to be different depending on food sources. In the lumen of the midgut of the lady beetle, though most of AP of live chicken liver lost its activity withtin 12 hours, that of M. cassicauda kept strong enzymatic activity up to 24 hours.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.278-283
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• 2005

Cement and paraffin waste form were prepared with a acid extraction method for the analysis of radionuclides generated from nuclear power plants. The acid extraction method was carried out with $HNO_3-HCl$ acid. At first, we compared the method with the microwave acid digestion method using SRM. The solutions of decomposed SRM were then analyzed by AAS and ICP-AES. The acid extraction method had shown good results as microwave acid digestion method. This method provided recovery values greater than $80\%$ for metallic elements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.842-853
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• 2014

For developing indigestible lipids, symmetric triacylglycerol (ST) and asymmetric triacylglycerol (AT) were produced by enzymatic interesterification using high oleic sunflower oil, palmitic ethyl ester, and stearic ethyl ester in a shaking water bath. Used enzymes were Lipozyme RMIM for ST and Lipozyme TLIM for AT. To remove ethyl ester from reactants, methanol fractionation (reactant : methanol=1:5, w/v, $25^{\circ}C$) and florisil separation (reactant : florisil=1:8, w/w) were applied. Acetone fractionation (reactant : acetone=1:9, w/v) was implemented to separate triacylglcerol (TAG) species into ST and AT. Fractions I (before fractionation), II (after fractionation, liquid phase) and III (after fractionation, solid phase) were separated from ST, whereas fractions IV (after 1st fractionation, liquid phase) and V (after 2nd fractionation, solid phase) were from AT. From sn-2 fatty acid composition analysis, the sum of palmitic acid (C16:0) and stearic acid (C18:0) was 4.9~6.5 area% in ST (I, II, III), and 41.9~43.9 area% in AT (IV, V). In vitro digestion was performed for 0, 15, 30, 60, and 120 minutes at $37^{\circ}C$ in a shaking water bath. For the digestion results, hydrolysis of V was only 40% compared to others (I, II, III, IV) at 120 minutes due to its melting point ($49^{\circ}C$). However, initially (15 minutes), hydrolysis (%) was as follows: V$32.5^{\circ}C$, $31.8^{\circ}C$) and different slip melting points ($31.3^{\circ}C$, $19.5^{\circ}C$). Even though IV has a lower TAG content composed of two saturated fatty acids than III, it had a similar melting point.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1659-1676
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• 2002

Ruminant animals develop a diverse and sophisticated microbial ecosystem for digesting fibrous feedstuffs. Plant cell walls are complex and their structures are not fully understood, but it is generally believed that the chemical properties of some plant cell wall compounds and the cross-linked three-dimensional matrix of polysaccharides, lignin and phenolic compounds limit digestion of cell wall polysaccharides by ruminal microbes. Three adaptive strategies have been identified in the ruminal ecosystem for degrading plant cell walls: production of the full slate of enzymes required to cleave the numerous bonds within cell walls; attachment and colonization of feed particles; and synergetic interactions among ruminal species. Nonetheless, digestion of fibrous feeds remains incomplete, and numerous research attempts have been made to increase this extent of digestion. Exogenous fibrolytic enzymes (EFE) have been used successfully in monogastric animal production for some time. The possibility of adapting EFE as feed additives for ruminants is under intensive study. To date, animal responses to EFE supplements have varied greatly due to differences in enzyme source, application method, and types of diets and livestock. Currently available information suggests delivery of EFE by applying them to feed offers the best chance to increase ruminal digestion. The general tendency of EFE to increase rate, but not extent, of fibre digestion indicates that the products currently on the market for ruminants may not be introducing novel enzyme activities into the rumen. Recent research suggests that cleavage of esterified linkages (e.g., acetylesterase, ferulic acid esterase) within the plant cell wall matrix may be the key to increasing the extent of cell wall digestion in the rumen. Thus, a crucial ingredient in an effective enzyme additive for ruminants may be an as yet undetermined esterase that may not be included, quantified or listed in the majority of available enzyme preparations. Identifying these pivotal enzyme(s) and using biotechnology to enhance their production is necessary for long term improvements in feed digestion using EFE. Pretreating fibrous feeds with alkali in addition to EFE also shows promise for improving the efficacy of enzyme supplements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1560-1565
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• 2004

There are about 50 kinds of salted and fermented fish in Korea, and they have been used as a necessity for the preparation of kimchi. There is next to nothing for the studies of finding out the cause of N-nitrosamine formation by using the salted and fermented anchovies. In order to predict the possibility of N-nitrosamine formation and mutagenicity from gastric digestion of Korean Jeotkal, correlation of N-nitrosodimethylamine (NDMA) and mutagenicity of the salted and fermented anchovy under simulated gastric digestion was investigated through mixture system of nitrate, thiocyanate, formaldehyde and ascorbic acid to the anchovy product aged at room temperature (18~20$^{\circ}C$) for 60 days. NDMA formation of fermented anchovy under simulated gastric digestion was accelerated by the increase of nitrate, thiocyanate and formaldehyde concentration and was inhibited by the addition of ascorbic acid as an inhibitor, showing that its inhibition rate was 71.3% at 4 mM as compared with control group. Mutagenicity in anchovy digest added with several level of nitrite, thiocyanate and formaldehyde was increased, while it was markedly decreased in addition of ascorbic acid.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.576-582
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• 1993

In order to investigate the inhibition of anaerobic digestion with alcohol-distillery wastes, batch anaerobic digestion experiments were conducted. Both naked-barley based and rice based alcohol-distillery wastes were separated into soluble organic fractions and suspended solids fraction using diafiltration with ceramic membranes. Each fraction of retentates and permeates, and the raw alcohol-distillery wastes were used as feeds for the anaerobic digestion study. The suspended solids fraction from the naked-barley stillages had produced much more propionic acid than the soluble organic fractions or raw alcohol-distillery wastes. The inhibition of anaerobic digestion for naked-barley alcohol-distillery wastes may be due to the higher productions of propionic acid with solids fraction of the wastes.