• Title/Summary/Keyword: Changes of microbial

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INFLUENCE OF DIRECT-FED MICROBIALS ON RUMINAL MICROBIAL FERMENTATION AND PERFORMANCE OF RUMINANTS: A REVIEW

  • Yoon, I.K.;Stern, M.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.6
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    • pp.533-555
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    • 1995
  • Direct-fed microbials (DFM) have been used to enhance milk production in lactating cattle and to increase feed efficiency and body weight gain in growing ruminants. Primary microorganisms that have been used as DFM for ruminants are fungal cultures including Aspergillus oryzae and Saccharomyces cerevisiae and lactic acid bacteria such as Lactobacillus or Streptococcus. Attempts have been made to determine the basic mechanisms describing beneficial effects of DFM supplements. Various modes of action for DFM have been suggested including : stimulation of ruminal microbial growth, stabilization of ruminal pH, changes in ruminal microbial fermentation pattern, increases in digestibility of nutrients ingested, greater nutrient flow to the small intestine, greater nutrient retention and alleviation of stress, however, these responses have not been observed consistently. Variations in microbial supplements, dosage level, production level and age of the animal, diet and environmental condition or various combinations of the above may partially explain the inconsistencies in response. This review summarizes production responses that have been observed under various conditions with supplemental DFM and also corresponding modification of ruminal fermentation and other changes in the gastrointestinal tract of ruminant animals.

Effect of Aqueous Chlorine Dioxide Treatment on the Microbial Growth and Qualities of Iceberg Lettuce during Storage

  • Kim, Yun-Jung;Lee, Seung-Hwan;Song, Kyung-Bin
    • Journal of Applied Biological Chemistry
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    • v.50 no.4
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    • pp.239-243
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    • 2007
  • Effects of aqueous chlorine dioxide ($ClO_2$) treatment on the microbial growth and the quality of iceberg lettuce during storage were examined. Lettuce samples were treated with 0, 5, 10, and 50 ppm of $ClO_2$ solution and stored at $4^{\circ}C$. Aqueous $ClO_2$ treatment significantly decreased the populations of total aerobic bacteria, yeasts and molds, and coliforms on the shredded lettuce. Fifty ppm $ClO_2$ treatment reduced the initial populations of total aerobic bacteria, yeasts and molds, and coliforms by 1.77, 1.34, 1.10 log CFU/g, respectively. Aqueous $ClO_2$ treatment caused negligible changes in the Hunter color L, a, and b values during storage. Sensory evaluations exhibited that there were no significant changes among treatments. These results indicate that the aqueous $ClO_2$ treatment can be useful in improving the microbial safety of the iceberg lettuce during storage and extending the shelf life.

Effects of red ginseng extract on gut microbial distribution

  • Kim, Young Kyun;Yum, Keun-Sang
    • Journal of Ginseng Research
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    • v.46 no.1
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    • pp.91-103
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    • 2022
  • Background: Red ginseng extract boosts immunity against inflammation and cancer in the human body. However, studies on the effects of red ginseng extract on the gut microbiome remain unexplored. Methods: In 2019, the positive effects and changes in the gut microbiome after administering 1 pack (3 g) of red ginseng extract per day to 53 adults aged 40 to 75 for 24 weeks were investigated. The gut microbial environment changes were qualitatively and quantitatively analyzed using next-generation sequencing and real-time polymerase chain reaction technology. Results: On comparing and analyzing alpha diversity and beta diversity, the microbial pattern showed significant differences (OTUs p = 0.003, chao1 p < 0.001, Bray-Curtis p = 0.001) before and after ingestion of red ginseng extract, indicating that gut microbial richness increased after ingestion. Moreover, after comparing and analyzing the gut microbiome's differences after red ginseng extract intake, significant differences were noted between three strains at the phylum level and among 57 strains at the genus level. Conclusion: This study proposes the potential use of red ginseng extract as a prebiotic after confirming its positive effects, including increasing gut microbiome richness, reducing harm to the gut microbiome, and increasing the number of some strains in the gut microbiome.

Ethanol Production from Artificial Domestic Household Waste Solubilized by Steam Explosion

  • Nakamura, Yoshitoshi;Sawada, Tatsuro
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.3
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    • pp.205-209
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    • 2003
  • Solubilization of domestic household waste through Steam explosion with Subsequent ethanol production by the microbial saccharifitation and fermentation of the exploded product was studied. The effects of steam explosion on the changes of the density, viscosity, pH, and amounts of extractive components in artificial household waste were determined. The composition of artificial waste used was similar to leftover waste discharged from a typical home in Japan. Consecutive microbial saccharification and fermentation, and simultaneous microbial saccharification and fermentation of the Steam-exploded product were attempted using Aspergillus awamori, Trichoderma viride, and Saccharomyces cerevisiae; the ethanol yields of each process were compared. The highest ethanol yield was obtained with simultaneous microbial saccharification and fermentation of exploded product at a steam pressure of 2 MPa and a steaming time of 3 min.

Changes in the Physico-chemical and Microbial Quality during the Production of Pastırma Cured with Different Levels of Sodium Nitrite

  • Aksu, Muhammet Irfan;Erdemir, Ebru;Cakici, Neslihan
    • Food Science of Animal Resources
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    • v.36 no.5
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    • pp.617-625
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    • 2016
  • Pastırma, a dry-cured meat product, is produced from the whole muscle and/or muscles obtained from certain parts of beef and water buffalo carcasses. The purpose of this study was to determine the effects of different levels of sodium nitrite on changes in the physicochemical and microbial quality during the production of pastırma. The changes in residual nitrite, salt, pH, moisture, thiobarbutiric acid reactive substances (TBARS), colour (L*, a*, b*), total aerobic mesophilic bacteria (TAMB), lactic acid bacteria (LAB), Micrococcus/Staphylococcus (M/S), mould-yeast (M-Y), and Enterobacteriaceae counts of pastırma with 0, 50, 100 and 150 ppm sodium nitrite were determined during the production. The nitrite levels and the production stages had significant effects (p<0.01) on residual nitrite, TBARS, pH, salt, and colour values. The TBARS values of the pastırma with nitrite were significantly lower (p<0.05) than the control. The final TAMB, LAB, M/S, and M-Y counts of pastırma with 150 ppm nitrite were significantly (p<0.05) lower than the control. Also, the a* (relative redness) values of control pastırma were significantly lower (p<0.05) than the pastırma with nitrite. The production stages had a significant effect (p<0.01) on the moisture.

Analysis of the Seasonal Change in Attached Algae and Microbial Community Structure in Sediment Basin Trough of Water Treatment Plant By Using Quinone Profile and PCR-DGGE (Quinone profile과 PCR-DGGE를 이용한 정수장 침전지에서의 부착조류 및 미생물군집의 계절적 변화해석)

  • Yu, Hyun-Sun;Lim, Byung-Ran;Ahn, Kyu-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.3
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    • pp.461-467
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    • 2006
  • The seasonal change in attached algae and microbial community structure at sedimentation basin of water treatment plant was investigated by using quinone profiles and denaturing gel gradient electrophoresis (DGGE). The photosynthetic bacteria and algae contains PQ-9 and VK-1 as major quinone are major component of the total quinone fraction in attached algae and microorganisms on sedimentation basin trough. The microorganisms containing menaquinones appear to be sensitivity to the change in temperature than those containing ubiquinones. The plot of the mole fraction of dominant quinone species ($f_d$) to the DQ values showed higher sensitivity to the seasonal change in the microbial community structure. The results indicated that quinone and DGGE are useful tool for the evaluation of the changes in the microbial community structure.

Quality Changes During Storage of Cook-chilled Soybean Sprouts

  • Koo, Kyoung-Mo;Kim, Hyoun-Wook;Lee, Dong-Sun;Lyu, Eun-Soon;Paik, Hyun-Dong
    • Food Science and Biotechnology
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    • v.17 no.3
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    • pp.540-546
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    • 2008
  • Sous vide and packaged cook-chilled soybean sprouts were evaluated for physicochemical quality changes and microbial safety during storage for the purposes of shelf-life extension and industrial application. The physicochemical changes assessed were color, texture, and ascorbic acid concentration. The quality of soybean sprouts became worse with increased periods of storage and better in storage temperature of $3^{\circ}C$ more than in $10^{\circ}C$. The concentration of aerobic bacteria decreased from $2.1{\times}10^8$ to $6.0{\times}10^2\;CFU/g$ after pasteurization, but increased during storage. These bacteria are the same shape as anaerobic and hsychrophilic bacteria, but none of these other organisms were detected after heat treatment. The physicochemical qualities of soybean sprouts and microbial safety were better for products stored at $3^{\circ}C$ than at $10^{\circ}C$. In the case of short storage periods, heat treatment at $70^{\circ}C$ for 2 min was most effective for quality and microbial safety.

Changes in Physicochemical Properties of Packaged Backsulgi during Storage (포장한 백설기의 저장과정 중 이화학적 변화)

  • 이경아;김경자
    • Korean Journal of Human Ecology
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    • v.5 no.2
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    • pp.45-54
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    • 2002
  • Packaged Backsulgi cooked by steam/convection oven and then rapidly chilled was examined by research of microbiological test and sensory evaluation while storing them at the temperatures of 3$^{\circ}C$ and 3$0^{\circ}C$ for 0, 2, 4, 6, 10 days . The pH and reducing sugar content were seemed to change little at 3$^{\circ}C$. However the pH was rapidly reduced until 4 days and then decreased a little at 3$0^{\circ}C$, the reducing sugar content was inclosed little by little. In the microbiological test, any microbial growth in total aerobic, psychrophilic, anaerobic, spore forming bacteria, yeast and molds was not observed until 10 days at 3$^{\circ}C$, but microbial changes of aerobic, psychrophilic and anaerobic bacteria increased to 6 logCFU/g until 10 days at 3$0^{\circ}C$. However microbial changes of them decreased from 6 logCFU/g to 5 logCFU/g. As a result of the sensory evaluation, appearance, taste, color, softness, chewiness and overall Quality were significantly decreased during storage times(p<0.05), but scores of taste and overall quality on 6th days were 7.38${\pm}$1.06, 7.00${\pm}$0.93. Therefore we concluded that there was no problem about stability of storage 6 days at 3$^{\circ}C$.

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Application of a Prototype of Microbial Time Temperature Indicator (TTI) to the Prediction of Ground Beef Qualities during Storage

  • Kim, Yeon-Ah;Jung, Seung-Won;Park, Hye-Ri;Chung, Ku-Young;Lee, Seung-Ju
    • Food Science of Animal Resources
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    • v.32 no.4
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    • pp.448-457
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    • 2012
  • The predictive ability for off-flavor development and quality change of ground beef was evaluated using a microbial time temperature indicator (TTI). Quality indices such as off-flavor detection (OFD) time, color, pH, volatile basic nitrogen (VBN), aerobic mesophilic bacteria (AMB) counts, and lactic acid bacteria (LAB) counts were measured during storage at 5, 10, 15, and $25^{\circ}C$, respectively. Arrhenius activation energies (Ea) were estimated for temperature dependence. The Ea values for TTI response (changes in titratable acidity (TA)), VBN, AMB counts, LAB counts, and freshness, which is defined based on OFD time for quality indices of ground beef, were 106.22 kJ/mol, 58.98 kJ/mol, 110.35 kJ/mol, 116.65 kJ/mol, and 92.73 kJ/mol, respectively. The Ea of microbial TTI was found to be closer to those of the AMB counts, LAB counts, and freshness. Therefore, AMB counts, LAB counts, and freshness could be predicted accurately by the microbial TTI response due to their Ea similarity. The microbial TTI exhibited consistent relationships between its TA change and corresponding quality indices, such as AMB counts, LAB counts, and freshness, regardless of storage temperature. Conclusively, the results established that the developed microbial TTI can be used in intelligent packaging technology for representing some selected quality indices of ground beef.

Studies on the Microbial Population and the Amylase Activity of the Forest Soil (삼림토양의 미생물군집과 아밀라아제 활성에 관한 연구)

  • Lee, Hee-Sun;Shim, Jae-Kuk
    • The Korean Journal of Ecology
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    • v.17 no.2
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    • pp.171-183
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    • 1994
  • Soil condition, total number of bacteria, soil amylase activity and microbial biomass $(CO_2-C)$ were measured at soil of different forest types. And the difference of the allelopathic effect was determined between fresh leaf extract of Quercus acutissima and Pinus rigida to the bacteria isolated from soil of different forest types. 1. Total number of bacteria in Carpinus laxiflora forest soil was 4~7 times larger than that in pinus desiflora forest soil. 2. Soil amylase activity was positively correlated with total number of soil bacteria and soil organic matter content. The amylase activity at F layer was 4~5 times larger than that at H layer, and that at H layer was 2~4 times larger than that at A layer. 3. Seasonal changes of microbial biomass showed a peak in summer, and vertical distribution of microbial biomass decreased with increasing soil depth. The microbial biomass in Pinus densiflora forest soil was larger than that in Quercus serrata forest soil. 4. Fresh leaf extract of Pinus rigida and Quercus acutissima showed an acceleration or inhibition effect on the growth of soil bacteria, and that of !. acutissima inhibited larger number of soil bacterial strains than that of P. rigida. 4.2% and 25% of soil bacterial strains isolated from soil of P. rigida and Q. acutissima forests were inhibited by fresh leaf extract of P. rigida and Q. acutissima, respectively.

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