• Ocean Science Journal
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• v.40 no.3
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• pp.145-153
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• 2005

Variation in the microbial biomass and community structure found in sediment of heavily polluted bays and the adjacent unpolluted areas were examined using phospholipid fatty acid analysis. Total microbial biomass and microbial community structure were responding to environmental determinants, sediment grain size, depth of sediment, and pollution due to petroleum hydrocarbons. The marker fatty acids of microeukaryotes and prokaryotes - aerobic, anaerobic, and sulfate-reducing bacteria - were detected in sediments of the areas studied. Analysis of the fatty acid profiles revealed wide variations in the community structure in sediments, depending on the extent of pollution, sediment depth, and sediment grain size. The abundance of specific bacterial fatty acids points to the dominance of prokaryotic organisms, whose composition differed among the stations. Fatty acid distributions in sediments suggest the high contribution of aerobic bacteria. Sediments of polluted sites were significantly enriched with anaerobic bacteria in comparison with clean areas. The contribution of this bacterial group increased with the depth of sediments. Anaerobic bacteria were predominantly present in muddy sediments, as evidenced from the fatty acid profiles. Relatively high concentrations of marker fatty acids of sulfate-reducing bacteria were associated with organic pollution in this site. Specific fatty acids of microeukaryotes were more abundant in surface sediments than in deeper sediment layers. Among the microeukaryotes, diatoms were an important component. Significant amounts of bacterial biomass, the predominance of bacterial biomarker fatty acids with abundance of anaerobic and sulfate-reducing bacteria are indicative of a prokaryotic consortium responsive to organic pollution.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.960-965
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• 2001

The effects of different feeding ratios of concentrate (C) and roughage (R) on balance of long chain fatty acids and microbial fatty acids in the rumen of sheep were investigated. The diets were divided into 8:2 (concentrate feeding), 4:6 (middle mixture) and 0:10 (roughage feeding) ratios (C:R). Duodenal digesta was collected through 24 hours after feeding. Biohydrogenation rate, total duodenal flow of fatty acids and microbial fatty acids were measured. Total duodenal flow of fatty acids was significantly (p<0.05) increased with increasing concentrate. Total duodenal flow of fatty acid was greater than intake of fatty acid in all diets. In comparison with intake of each fatty acid, duodenal flow of stearic acid ($C_{18:0}$) remarkably increased in all diets. Biohydrogenation rate for total C18 unsaturated fatty acids in the rumen tended to increase (p<0.10) when sheep were fed the middle mixture. In particular, biohydrogenation rate of linoleic acid ($C_{18:2}$) and linolenic acid ($C_{18:3}$) with the middle mixture were highest (p<0.05) compared with other diets. Duodenal flow of protozoal fatty acids was significantly (p<0.05) increased with the increased supply of concentrate. That of bacterial fatty acids was significantly (p<0.05) increased with both concentrate diets compared with the roughage feeding diet. $C_{18:0}$ occupied the greater part of both protozoal and bacterial fatty acids in all treatments. Results indicated that biohydrogenation of free unsaturated fatty acids was actively carried out when the middle mixture diet was supplied, and that microbial uptake and synthesis of fatty acids were accelerated by adding the supply of concentrate.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.99-101
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• 1981

Attempts were made to investigate on the fatty acids of Lentinus lepideus Fr. Fats were extracted from its carpophores and saponified with alcoholic potassium hydroxide. Isolated fatty acids were methylated and were subjected to column chromatography and GLC. Six saturated fatty acids, i.e., dodecanoic, tridecanoic, tetradecanoic, pentadecanoic, hexadecanoic and octadecanoic acids were identified. Especially myristic acid was abundant. Four unsaturated fatty acids, i.e., hexadecadienoic, oleic, linoleic, linolenic acids, were identified. Especially oleic and linoleic acid were abundant.

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.5-8
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• 1978

Attempts were made to investigate on the fatty acids of Agaricus bisporus, a cultivated edible mushroom. Fats were extracted from it and saponified with alcoholic potassium hydroxide. Isolated fatty acids were methylated and were subjected to column chromatography and G.L.C. Eleven saturated fatty acids, i.e., dodecanoic, tridecanoic, tetradecanoic, pentadecanoic, hexadecanoic, heptadecanoic, octadecanoic, eicosenoic, uncosenoic, docosenoic, and tricosenoic acids, were identified. Especially palmitic and stearic acids were abundant. Nine unsaturated fatty acids appear to exist in the carpophore.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1184-1192
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• 2011

A bacterial isolate (strain JS-2) characterized as Bacillus sp. was challenged with high concentrations of toxic selenite ions. The microbe was found to transform the toxic, soluble, colorless selenite (${SeO_3}^{2-}$) oxyions to nontoxic, insoluble, red elemental selenium ($Se^0$). This process of biotransformation was accompanied by cytoplasmic and surface accumulation of electron dense selenium ($Se^0$) granules, as revealed in electron micrographs. The cells grown in the presence of selenite oxyions secreted large quantities of extracellular polymeric substances (EPS). There were quantitative and qualitative differences in the cell wall fatty acids of the culture grown in the presence of selenite ions. The relative percentage of total saturated fatty acid and cyclic fatty acid increased significantly, whereas the amount of total unsaturated fatty acids decreased when the cells were exposed to selenite stress. All these physiological adaptive responses evidently indicate a potentially important role of cell wall fatty acids and extracellular polymeric substances in determining bacterial adaptation towards selenite-induced toxicity, which thereby explains the remarkable competitiveness and ability of this microbe to survive the environmental stress.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.176-181
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• 2000

In order to clarify the inhibitory effects of orchardgrass (Dactylis glomerata L.) lipids on ruminal fermentation and digestion, two experiments were carried out in vitro. Experiment 1 was carried out using residues of grass hay from which the lipid fraction was removed by ether extraction. To ground grass samples were added 0, 1.5, 3.0, 4.5 and 6.0% lipids and incubated anaerobically at $39^{\circ}C$ for 24 h, with the mixtures of artificial saliva and rumen fluid. Increasing grass lipid levels remarkably reduced DM and NDF disappearances. Volatile fatty acid concentration was significantly reduced at 3.0, 4.5 and 6.0% lipid levels. Microbial nitrogen proportion to total nitrogen tended to decrease by the addition of the lipids. These results indicated that grass lipids have a marked inhibitory effect on ruminal fermentation and digestion, especially when to the substrate was added 3% or more grass lipids as ether extracts. Experiment 2 was conducted to study the relationship between changes in the free fatty acids and changes in the fermentation traits. Samples were incubated for 3, 6, 9, 12, 15, 18, 21 and 24 h as a sole substrate. The polyunsaturated fatty acids steadily decreased during incubation, whereas the saturated fatty acid ($C_{18:0}$) increased. It was suggested that the hydrogenation was extended during the initial stage of incubation. The unsaturated fatty acids ($C_{18:2}$, $C_{18:3}$) produced at the initial stage of incubation were negatively correlated with the amount of microbial N and DM disappearance, indicating that polyunsaturated fatty acids had the possibility to show an inhibiting effect on ruminal fermentation and digestion.

• Archives of Pharmacal Research
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• v.2 no.2
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• pp.133-144
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• 1979

To investigate constituents of Strobilomyces floccopus (Fr.) Karst. and Coprinus comatus (Fr.) S. F. Gray, free and total amino acids of the two mushrooms were quantitatively analyzed by G. L. C. and an amino acid analyzer. Free amino acids were extracted from both mushrooms with ethanol. Fourtenn free amino acids were detected from the ethanol extract of S. floccopus and fifteen free amino acids from C. comatus by G. L. C. And the dry carphopores of both mushrooms were hydrolyzed with hydrochloric acid and then the total protein amino acids were analyzed by A. A. A. Seventeen total amino acids were detected from each acid-hydrolysate of S. floccopus and C. comatus. Lipids were extracted from the carpophores of S. floccopus and saponified with alcoholic potassium hydroxide. The isolated sterols were subjected to G. L. C. and two sterols were detected. The isolated free fatty acids were methylated with diazomethane and subjected to column chromatography and G. L. C. Eleven saturated and nine unsaturated free fatty acids were detected from the carpophores of S. floccopus. The presence of these nutrient components shows that the two mushrooms can be utilized as edible ones.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1590-1597
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• 2017

Objective: This study aims to identify the relationship between odd- and branched-chain fatty acids (OBCFAs) and microbial nucleic acid bases in the rumen, and to establish a model to accurately predict microbial protein flow by using OBCFA. Methods: To develop the regression equations, data on the rumen contents of individual cows were obtained from 2 feeding experiments. In the first experiment, 3 rumen-fistulated dry dairy cows arranged in a $3{\times}3$ Latin square were fed diets of differing forage to concentration ratios (F:C). The second experiment consisted of 9 lactating Holstein dairy cows of similar body weights at the same stage of pregnancy. For each lactation stage, 3 cows with similar milk production were selected. The rumen contents were sampled at 4 time points of every two hours after morning feeding 6 h, and then to analyse the concentrations of OBCFA and microbial nucleic acid bases in the rumen samples. Results: The ruminal bacteria nucleic acid bases were significantly influenced by feeding diets of differing forge to concentration ratios and lactation stages of dairy cows (p<0.05). The concentrations of OBCFAs, especially odd-chain fatty acids and C15:0 isomers, strongly correlated with the microbial nucleic acid bases in the rumen (p<0.05). The equations of ruminal microbial nucleic acid bases established by ruminal OBCFAs contents showed a good predictive capacity, as indicated by reasonably low standard errors and high R-squared values. Conclusion: This finding suggests that the rumen OBCFA composition could be used as an internal marker of rumen microbial matter.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.724-735
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• 2023

NdgR, a global regulator in soil-dwelling and antibiotic-producing Streptomyces, is known to regulate branched-chain amino acid metabolism by binding to the upstream region of synthetic genes. However, its numerous and complex roles are not yet fully understood. To more fully reveal the function of NdgR, phospholipid fatty acid (PLFA) analysis with gas chromatography-mass spectrometry (GC-MS) was used to assess the effects of an ndgR deletion mutant of Streptomyces coelicolor. The deletion of ndgR was found to decrease the levels of isoleucine- and leucine-related fatty acids but increase those of valine-related fatty acids. Furthermore, the defects in leucine and isoleucine metabolism caused by the deletion impaired the growth of Streptomyces at low temperatures. Supplementation of leucine and isoleucine, however, could complement this defect under cold shock condition. NdgR was thus shown to be involved in the control of branched-chain amino acids and consequently affected the membrane fatty acid composition in Streptomyces. While isoleucine and valine could be synthesized by the same enzymes (IlvB/N, IlvC, IlvD, and IlvE), ndgR deletion did not affect them in the same way. This suggests that NdgR is involved in the upper isoleucine and valine pathways, or that its control over them differs in some respect.

• Ocean Science Journal
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• v.42 no.4
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• pp.247-254
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• 2007

Marine bacteria, actionmycetes and fungal strains were isolated from continental slope sediment of the Bay of Bengal and studied for fatty acid profile to investigate their involvement in the benthic food-web. Fifteen different saturated and unsaturated fatty acids from bacterial isolates, 14 from actinomycetes and fungal isolates were detected. The total unsaturated fatty acids in bacterial isolates ranged from 11.85 to 37.26%, while the saturated fatty acid ranged between 42.34 and 80.74%. In actinomycetes isolates, total unsaturated fatty acids varied from 27.86 to 38.85% and saturated fatty acids ranged from 35.29 to 51.25%. In fungal isolates unsaturated fatty acids ranged between 44.62 and 65.52% while saturated FA ranged from 20.80 to 46.30%. The higher percentages of unsaturated fatty acids from the microbial isolates are helpful in anticipating the active participation in the benthic food-web of Bay of Bengal.