• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1381-1388
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• 2012

An in vitro experiment was conducted to examine the effects of defaunation (removal of protozoa) on ruminal fermentation characteristics, $CH_4$ production and degradation by rumen microbes when incubated with cereal grains (corn, wheat and rye). Sodium lauryl sulfate as a defaunation reagent was added into the culture solution at a concentration of 0.000375 g/ml, and incubated anaerobically for up to 12 h at $39^{\circ}C$. Following defaunation, live protozoa in the culture solution were rarely observed by microscopic examination. A difference in pH was found among grains regardless of defaunation at all incubation times (p<0.01 to 0.001). Defaunation significantly decreased pH at 12 h (p<0.05) when rumen fluid was incubated with grains. Ammonia-N concentration was increased by defaunation for all grains at 6 h (p<0.05) and 12 h (p<0.05) incubation times. Total VFA concentration was increased by defaunation at 6 h (p<0.05) and 12 h (p<0.01) for all grains. Meanwhile, defaunation decreased acetate and butyrate proportions at 6 h (p<0.05, p<0.01) and 12 h (p<0.01, p<0.001), but increased the propionate proportion at 3 h, 6 h and 12 h incubation (p<0.01 to 0.001) for all grains. Defaunation increased in vitro effective degradability of DM (p<0.05). Production of total gas and $CO_2$ was decreased by defaunation for all grains at 1 h (p<0.05, p<0.05) and then increased at 6 h (p<0.05, p<0.05) and 12 h (p<0.05, p<0.05). $CH_4$ production was higher from faunation than from defaunation at all incubation times (p<0.05).

• Food Science of Animal Resources
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• v.30 no.1
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• pp.154-162
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• 2010

This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

• Korean journal of food and cookery science
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• v.14 no.1
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• pp.106-113
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• 1998

The purpose of this study is to investigate the antimicrobial effect of mugwort (Artemisia asiatica Nakai) on the rice cake and bread preservation, and to identify their antimicrobial compounds. The mugwort extracts showed complete inhibition on the growth of Bacillus subtilis and Staphylococcus aureus at 250 $\mu\textrm{g}$/ml level. Antimicrobial activi쇼 of mugwort extract were stronger than that of commercial antimicrobial agent. Five % of sodium propionate solution showed complete inhibition on the growth of B. subtilis, E. coli and S. aureus, but L. plantarum was inhibited 50.87% at the same concentration. When various amounts of freeze-dried mugwort powder were added in sulgis (steamed rice cake), 3% ssooksulgi (mugwort powder added sulgi) had quite lower level of total bacterial count (5.5$\times$$10^/5 CFU/g) compared with the control group (1.4$\times$$10^/7 CFU/g) at ambient temp. (30$\pm$1$^{\circ}C$) after 72 hr. Three % addition of mugwort showed 2 days extention of shelf-life of rice cake. The sensory qualities of ssooksulgi has no significant difference in moistness, consistency, cohesiveness, afterswallowing and overall quality compared with control group. Ssooksulgi with 3% of mugwort powder had the best overall quality in sensory test. The methanol extract of 500 $\mu\textrm{g}$/ml of mugwort could lead the successful retardation of the growth of putrefactive microorganism during the incubation of rice cake at 37$^{\circ}C$ for 24 hr. On the other hand, coumarin (Sigma) had 54% inhibitory effect at 500 $\mu\textrm{g}$/ml level, and (E,E)-2,4-decadienal completely inhibited the growth of putrefactive microorganism of whitesulgi at 100 $\mu\textrm{g}$/ml level during the incubation at 37$^{\circ}C$ for 48 hr.48 hr.

• Korean journal of food and cookery science
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• v.14 no.1
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• pp.119-123
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• 1998

The purpose of this study was to evaluate the antimicrobial effect of green laver (Enteromorpha linza) on the muk (starch jelly) preservation. The methanol extract of green laver completely inhibited the growth of Vibrio parahaemolyticus at 500 $\mu\textrm{g}$/ml level, and inhibited the growth of Bacillus subtilis, Escherichia coli and Staphylococcus aureus at 100 $\mu\textrm{g}$/ml level. The Listeria monocytogenes was inhibited by 98.89% at the same concentration. When various amounts of green laver powder were added in muk (starch jelly), 5% of green laver powder-added muk showed very low level of total bacterial count compared with the control group. Also, green laver did not give negative sensory qualities such as color, flavor and overall quality. Five % green laver muk was selected as the most preferable sample among the green laver muks in overall quality test.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.1
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• pp.48-53
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• 2001

An in vitro study was conducted to examine the effect of sources and the addition levels of carbohydrates on fermentation characteristics, bacterial growth, and hydrogenation of linoleic acid ($C_{18:2}$) by mixed ruminal bacteria. Starch and cellobiose were added to the 200 ml non-selective basal media at the levels of 0.20 and 0.35% (w/v), respectively. Linoleic acid (66.8~79.6 mg) in the absorbed form into the pieces of nylon cloth was also added to the media of 5 treatments including control which was not added with carbohydrate. Three mls of rumen fluid strained through 12 layers of cheese cloth were added to each medium, and were incubated anaerobically in the shaking incubator of $39^{\circ}C$ for 24 hours. During 24 h incubation the pH in incubation media of all treatments was maintained above 6.6 by the addition of sodium bicarbonate. The pH and ammonia concentration of incubation media were not clearly influenced by the sources and addition levels of carbohydrates while additions of carbohydrates increased (p<0.0001) VFA concentration at the 24 h incubation. Molar proportions of acetate were reduced (p<0.0004) while those of propionate were increased (p<0.0006) by the addition of carbohydrates. But the differences in concentration and molar proportions of the VFA were small between the sources or the addition levels. Bacterial growth was faster (p<0.0004) in the starch added treatments than in the cellobiose added ones and control, but no differences were found between addition levels. Increased (p<0.0487) hydrogenation was observed from the starch added treatments compared to the cellobiose added ones, but there was no difference between addition levels.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.967-973
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• 2000

A metabolism trial was conducted with 28 Najdi rams allocated into seven dietary groups to evaluate the effect of dietary inclusion of Salicornia bigelovii Torr biomass on nutrient digestibility, rumina I fluid metabolites and nitrogen and mineral balances. Either the stems (ST) or spikes (SP) of this seawater-irrigated halophyte were incorporated into complete diets at rates of 0, 10, 20 and 30% levels, replacing equal amounts of rhodesgrass hay in a ground mixed control diet. Digestibility of DM, OM, EE, NFE and fecal and urinary nitrogen were not affected by increased level of ST in the diet. As level of ST increased from 0 to 20% in the diets, CP digestibility and nitrogen retention approached their maximum (p<0.01), whereas CF digestibility reached its minimum (p<0.01). On the other hand, except for EE, digestion of all nutrients and nitrogen retention were linearly depressed (p<0.01) as SP increased in the diets from 10 to 30% level. Concentration of ammonia-N, total VFA and pH values in the rumen fluid were lower (p<0.01) with the ST- or SP-fed diets than with the control diet. Increasing level of ST or SP in the diet was associated with an increase (p<0.01) in the proportion of acetate and a decline (p<0.01) in molar percentage of propionate in the ruminal fluid. Sodium absorption increased (p<0.01) with increased ST and SP in the diets up to the 10 and 20% level, respectively, followed by constant absorption values up to the 30% level. When the level of ST in the diet gradually increased to 30%, a concomitant increased (p<0:01) in Ca and P absorption were obvious; whereas, increased level of SP in the diets from 0 to 30% resulted in noticeable (p<0.01) depression in Ca and P apparent absorption.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.507-514
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• 1994

Acetyl xylan esterase was produced by E. coli HB101 harboring a recombinant plasmid pKMG6 which contained the estI gene of Bacillus stearothermophilus. The maximum production was observed when the E. coli strain was grown at 37$\circC for 12 hours in the medium containing 0.5% acetyl xylan, 1.0% tryptons, 1.0% sodium chloride, and 0.5% yeast extract. The esterase produced was purified to homogeneity using a combination of ammonium sulfate fractionation, DEAE Sepharose CL-6B ion exchange chromatography and Sephacryl S-200 gel filtration. The native enzyme had an apparent molecular mass of 60 kd and was composed of two identical subunits of 29 kd. The N-terminal amino acid sequence of the polypeptide was Ala-X-Leu-Gln- Ile-Gln-Phe-X-X-Gln. The acetyl esterase displayed a pH optimum of 6.5 and a temperature opti- mum of 45$\circC. The heavy metal ions such as Ag$^{++}$, Hg$^{++}$ and Cu$^{++}$ inhibited nearly completely the activity of the esterase, and no specific metal ion was found to be required for the enzyme activity. The enzyme readily cleaved MAS, $\beta$-D-glucose pentaacetate, $\alpha$-naphthyl acetate, $\rho$-nitrophenyl acetate as well as acetyl xylan, but had no activity on $\rho$-nitrophenyl propionate, $\beta$-nitrophenyl butyrate or $\beta$-nitrophenyl valerate. The Km and Vmax values for MAS were 2.87 mM and 11.55 $\mu$mole/min, respectively. Synergistic behavior was demonstrated with a combination of xylanase and esterase from B. stearothermophilus in hydrolyzing acetyl xylan.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.3
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• pp.197-205
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• 2013

An in vitro study was conducted to determine the effects of defaunation (removal of protozoa) and forage sources (rice straw, ryegrass and tall fescue) on ruminal fermentation characteristics, methane ($CH_4$) production and degradation by rumen microbes. Sodium lauryl sulfate, as a defaunation reagent, was added into the mixed culture solution to remove ruminal protozoa at a concentration of 0.375 mg/ml. Pure cellulose (0.64 g, Sigma, C8002) and three forage sources were incubated in the bottle of culture solution of mixed rumen microbes (faunation) or defaunation for up to 24 h. The concentration of ammonia-N was high under condition of defaunation compared to that from faunation in all incubations (p<0.001). Total VFA concentration was increased at 3, 6 and 12 h (p<0.05~p<0.01) but was decreased at 24 h incubation (p<0.001) under condition of defaunation. Defaunation decreased acetate (p<0.001) and butyrate (p<0.001) proportions at 6, 12 and 24 h incubation times, but increased propionate (p<0.001) proportion at all incubation times for forages. Effective degradability of dry matter was decreased by defaunation (p<0.001). Defaunation not only decreased total gas (p<0.001) and $CO_2$ (p<0.01~0.001) production at 12 and 24 h incubations, but reduced $CH_4$ production (p<0.001) at all incubation times for all forages. The $CH_4$ production, regardless of defaunation, in order of forage sources were rice straw > tall fescue > ryegrass > cellulose (p<0.001) up to 24 h incubation.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.221-231
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• 1998

The biosynthesis of galactolipid and the composition of fatty acid in chloroplast and thylakoid envelope isolated from C. ellipsoidea treated with antiseptics (potassium sorbate: PS, sodium benzoate:SB, calcium propionate:CP) were analyzed. The contents of monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG) and total lipid in treatment with antiseptics were lower to compared with the control. The major fatty acid utilized for biosynthesis of MGDG in chloroplast envelope were palmitoleic acid (ave. 15.55%), oleic acid (ave. 15.09%) in control. Otherwise, the major fatty acids in P.S treatment were utilized for oleic acid (ave. 13.71%), linolenic acid (ave. 14.36%), palmitoleic acid (ave. 18.26%), oleic acid (ave. 17.26%) in S.B treatment, and oleic acid (ave. 16.88%), palmitoleic acid (ave. 16.31%) in CP treatment. It was showed that the major fatty acids in chloroplast envelope DGDG were oleic acid (ave. 15.75%), linolenic acid (ave. 17.74%) in control, oleic acid (ave. 14.90%), palmitoleic acid (ave. 15.97%) in P.S treatment, palmitoleic acid (ave. 13.29%), oleic acid (ave. 15.74%) in S.B treatment, and oleic acid (ave. 14.52%), palmitoleic acid (ave. 14.03%) in C.P treatment. The major fatty acid utilized for biosynthesis of MGDG in thylakoid envelope were linolenic acid (ave. 14.78%), oleic acid (ave. 12.90%) in control. Otherwise, the major fatty acids were utilized for palmitoleic acid (ave. 13.00%), palmitic acid (ave. 13.00%) in P.S treatment, palmitoleic acid (ave. 12.94%), oleic acid (ave. 12.43%) in S.B treatment, and oleic acid (ave. 12.43%), palmitoleic acid (ave. 12.43%) in C.P treatment. It was showed that the major fatty acids in thylakoid envelope DGDG were linolenic acid (ave. 18.01 %), oleic acid (ave. 15.53%) in control, linolenic acid (ave. 19.20%), linoleic acid (ave. 14.14%) in P.S treatment, palmitoleic acid (ave. 9.03%), oleic acid (ave. 14.85%) in S.B treatment, oleic acid (ave. 13.90%), linolneic acid(ave. 12.66%) in C.P treatment.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.775-787
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• 2018

This study was conducted to investigate for the natural methane emission inhibitor as a feed additive no adversely effect on rumen fermentation. Five different Control (Wheat barn (0.05 g), MRA(Methane Reduction Additive)-1 (Allium fistulosum L. (0.05 g)), MRA-2 (Sodium Lauryl Sulfate (0.025 g) + Wheat barn (0.025 g) mixed), MRA-3 (Sodium Dodecyl Sulfate (0.025 g) + Wheat barn (0.025 g) mixed), and MRA-4 (Allium fistulosum L. (0.02 g) + Tannic acid (0.02 g) + Wheat barn (0.01 g) mixed) contents were used to perform 3, 6, 9, 12, 24 and 48 h incubation for in vitro fermentation. Ruminal pH values were ranged within normal ruminal microbial fermentation. Dry matter digestibility was not significantly different across the treatments during the whole fermentation time. Also, the result of microbial growth had no adversely effect on during the whole fermentation time. At 24 h, methane emission was significantly lower (P<0.05) than all treatments except to MRA-1. Especially, MRA-4 carbon dioxide emission was significantly lower (P<0.05) than control at 9, 24 and 48 h incubation. In addition MRA-4 propionate concentration was significantly higher (P<0.05) than control at 24 h incubation. The result of RT-PCR Ciliate-associated methanogens were significantly lower (P<0.05) at MRA-1, MRA-3 and MRA-4 than control at 24 h incubation. Based on the present results, MRA-4 could be suggestible methane emission inhibitor as a natural feed additive.