• Journal of Microbiology
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• v.44 no.3
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• pp.354-359
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• 2006

This study examined the capacity of immobilized bacteria to degrade petroleum hydrocarbons. A mixture of hydrocarbon-degrading bacterial strains was immobilized in alginate and incubated in crude oil-contaminated artificial seawater (ASW). Analysis of hydrocarbon residues following a 30-day incubation period demonstrated that the biodegradation capacity of the microorganisms was not compromised by the immobilization. Removal of n-alkanes was similar in immobilized cells and control cells. To test reusability, the immobilized bacteria were incubated for sequential increments of 30 days. No decline in biodegradation capacity of the immobilized consortium of bacterial cells was noted over its repeated use. We conclude that immobilized hydrocarbon-degrading bacteria represent a promising application in the bioremediation of hydrocarbon-contaminated areas.

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1993-2005
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• 2019

Thermophilic anaerobic digestion (TAD) is characterized by higher biogas production rates as a result of assumedly faster microbial metabolic conversion rates compared to mesophilic AD. It was hypothesized that the thermophilic microbiome with its lower diversity than the mesophilic one is more susceptible to disturbances introduced by alterations in the operating factors, as an example, the supply of nitrogen-rich feedstock such as poultry manure (PM). Laboratory scaled TAD experiments using cattle slurry and increasing amounts of PM were carried out to investigate the (in-) stability of the process performance caused by the accumulation of ammonium and ammonia with special emphasis on the microbial community structure and its dynamic variation. The results revealed that the moderate PM addition, i.e., 25% (vol/vol based on volatile substances) PM, resulted in a reorganization of the microbial community structure which was still working sufficiently. With 50% PM application, the microbial community was further stepwise re-organized and was able to compensate for the high cytotoxic ammonia contents only for a short time resulting in consequent process disturbance and final process failure. This study demonstrated the ability of the acclimated thermophilic microbial community to tolerate a certain amount of nitrogen-rich substrate.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.7
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• pp.990-996
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• 2005

The effect of diets varying in level and source of nitrogen (N) and fermentable organic matter on dynamic characteristics of microbial populations in rumen liquor and their impact on substrate fermentation in vitro was studied. The diets tested were straw alone, straw+concentrate mixture and straw+urea molasses mineral block (UMMB) lick. The same diets were taken as substrates and tested on each inoculum collected from the diets. Diet had no effect on the amino acid (AA) composition of either bacteria or protozoa. Differences among the diets in intake, source of N and OM affected bacterial and protozoal characteristics in the rumen. Upper asymptote of gas production (Y$\alpha$) had a higher correlation with bacterial pool size and production rate than with protozoal pool size and production rate. Among the parameters of the gas production model, Y$\alpha$ and lag time in total gas has showed significant (p<0.01) correlation with bacterial characteristics. Though the rate constant of gas production significantly differed (p<0.01) between diet and type of straw, it was least influenced by the microbial characteristics. The regression coefficient of diet and type of straw for Y$\alpha$ indicated that the effect of diet on Y$\alpha$ was threefold higher than that of the straw. As microbial characteristics showed higher correlation with Y$\alpha$, and diet had more influence on the microbial characteristics, gas production on a straw diet could be used effectively to understand the microbial characteristics.

• Journal of the Korean Society of Industry Convergence
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• v.17 no.3
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• pp.170-177
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• 2014

This study was conducted to know the behavior of pH behavior in the tomato juices to find out an effective medium for microbial cultivation. Bacterial culture media is a material consist a mixture of nutrients used to grow microorganisms on or in it. In addition, microbial culture media can also be used for isolation, propagation, testing the nature physiological, and calculation of the number of microorganisms. Fresh tomato juice is used for basic ingredient, therein added salt, sugar and EM (Effective Microbial). The fermented solution placed in a room with a temperature of 40oC. Data retrieval before the pH value reached a constant value is done every 12 hours, after constant rate data collection was done every 24 hours. The pH value has been steady after 372 hours of fermentation process (15.5 days). From the results obtained that the amount of additional ingredient which added into tomato juice does not affect final pH value of solution. Thereby the most effective treatment for microbial cultivation media is treatment number four.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.301-307
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• 2011

Oil pollution was world-wide prevalent treat to the environment, and the physic-chemical remediation technology of the TPH (total petroleum hydrocarbon) contaminated soil had the weakness that its rate was very slow and not economical. Bioremediation of the contaminated soil is a useful method if the concentrations are moderate and non-biological techniques are not economical. The aim of this research is to investigate the influence of additives on TPH degradation in a diesel contaminated soil environment. Six experimental conditions were conduced; (i) diesel contaminated soil, (ii) diesel contaminated soil treated with microbial additives, (iii) diesel contaminated soil treated with microbial additives and the mixture was titrated to the end point of pH 7 with NaOH, (iv) diesel contaminated soil treated with microbial additives and accelerating agents and (v) diesel contaminated soil treated with microbial additives and accelerating agents, and the mixture was titrated to the end point of pH 7 with NaOH. After 10 days, significant TPH degradation (67%) was observed in the DSP-1 soil sample. The removal of TPH in the soil sample where microbial additives were supplemented was 38% higher than the control soil sample during the first ten days. The microbial additives were effective in both the initial removal rate and relative removal efficiency of TPH compared with the control group. However, various environmental factors, such as pH and temperature, also affected the activities of microbes lived in the additives, so the pH calibration of the oil-contaminated soil would help the initial reduction efficiency in the early periods.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.103-108
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• 2022

This study investigated the strains and fermentation characteristics of used to ferment a mixture of rice and soybeans to manufacture low-salt doenjang for flavoring. The soybean and rice mixture was fermented using three selected strains of Aapergillus oryzae and Bacillus sp. The changes in quality of the fermented products were found to be dependent on the aging period. Therefore, the strain and a suitable aging period were seleted based on the increases in AN, total sugar, and reducing sugar. The fermented products were prepared and mixed, using the selected or commercially available strains (the sample and control, respectively), to create low-salt doenjang. Following this, their characteristics were compared. The sample had a higher content of taste-related ingredients(free amino acid, nucleic acid-related substances) than the control. Using the selected strain to ferment a rice and soybean mixture will thus be expected to enhance the flavor of industrially produced seasoned doenjang.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1444-1452
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• 2007

An in vitro experiment was conducted to evaluate the differences in microbial activity of five faecal inocula from weaned pigs and one faecal inoculum from unweaned pigs in combination with 6 substrates. The substrates tested were negative control diet, corn, soybean meal, oligofructose (OF), ground chicory roots and a mixture (60% chicory pulp and 40% OF). The inocula used were derived from pigs fed either a corn-soy based diet without antibiotics (NCON), the NCON diet supplemented with oligofructose (OF), a mixture of chicory pulp (40%) and OF (60%) (MIX), ground chicory roots (CHR) or the NCON diet supplemented with antibiotics (PCON). The cumulative gas production measured fermentation kinetics and end products, such as total gas production, ammonia and volatile fatty acids, were also determined. Both the substrate and the inoculum significantly affected the fermentation characteristics. The cumulative gas production curve showed that different substrates caused more differences in traits of fermentation kinetics than the different inocula. Inocula of weaned pigs gave a significantly higher VFA production compared to the inoculum from unweaned animals, whilst the rate of fermentation and the total gas produced did not differ. OF showed the highest fermentation kinetics and the lowest $NH_3$, pH and OM loss compared to other substrates. It was concluded that the microbial activity was significantly affected by substrate and inoculum. Inoculum from weaned pigs had more potential for microbial fermentation of the carbohydrate ingredients and oligofructose than that of unweaned pigs. A combination of high and low polymer inulin may be more beneficial to the gut ecosystem than using high- or low-polymer inulin alone.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.994-1000
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• 1994

Hot water extract from mugwort (Artemisia asiatica nakai) leaves and tea inhibited the growth of Bacillus subtilis by adding to the nutrient broth 1.0% and 0.5% concentration, respectively. Among the important compounds that contributing mugwort like flavor to the mugwort leaves and tea were considered, authenic compound of thujone, caryophyllene and farnesol showed bactericidal effect for Escherichia coli, Enterobacter aerogenes, Vibrio paraheaemolyticus, Psudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus when teste by paper disc method ( 8 mm diameter). The mixture of caryophyllene and farnesol was more bactericidal effect for various bacteria than the mixture of thujone, caryophyllene and farnesol was more bactericidal effect for various bacteria that the mixture of thujone, caryophyllene and farnesol or each compounds . Especially, the mixture of caryophyllene and farnesol showed strong bactericidal effect (diameter of inhibition zone>40mm) for Vibrio parahaemolyticus , Enterobacter aerogenes and BAcillus subtilis.

• The Korean Journal of Mycology
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• v.9 no.3
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• pp.153-155
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• 1981

Attempts were made to investigate on sterols of Cryptoporus volatus (Pk.) Hubb.. Its carpophores were collected in Gyeong Gi Province and extracted with a mixture of chloroform and methanol. From the extract eight spots were detected by T.L.C.. One of the spots was identified as ergosterol by T.L.C., G.L.C. and chemical tests.

• Journal of Biosystems Engineering
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• v.42 no.3
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• pp.170-189
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• 2017

Purpose: This paper presents Raman chemical imaging technology for inspecting food and agricultural products. Methods The paper puts emphasis on introducing and demonstrating Raman imaging techniques for practical uses in food analysis. Results & Conclusions: The main topics include Raman scattering principles, Raman spectroscopy measurement techniques (e.g., backscattering Raman spectroscopy, transmission Raman spectroscopy, and spatially offset Raman spectroscopy), Raman image acquisition methods (i.e., point-scan, line-scan, and area-scan methods), Raman imaging instruments (e.g., excitation sources, wavelength separation devices, detectors, imaging systems, and calibration methods), and Raman image processing and analysis techniques (e.g., fluorescence correction, mixture analysis, target identification, spatial mapping, and quantitative analysis). Raman chemical imaging applications for food safety and quality evaluation are also reviewed.