• Title/Summary/Keyword: biogenic

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The Sediment-Water Interface Increment due to the Complex Burrows of Macrofauna in a Tidal Flat

  • Koo, Bon-Joo;Kwon, Kae-Kyoung;Hyun, Jung-Ho
    • Ocean Science Journal
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    • v.40 no.4
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    • pp.221-227
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    • 2005
  • The architecture of macrofaunal burrows and the total area of the sediment-water interface created by biogenic structure were investigated in the Donggeomdo tidal flat on the west coast of Korea. Resin casting methods were applied to recover burrows of four dominant species, Macrophthalmus japonicus, Cleistostoma dilatatum, Perinereis aibuhitensis, and Periserrula leucophryna, and whole burrows within the casting area at three sites in different tidal levels. P. leucophryna excavated the largest burrow in terms of a surface area among them. In the case of whole burrow casting, the space occupied by the biogenic structure was extended into deeper and expanded more greatly at the higher tidal level. In the uppermost flat, the burrow wall surface area within sediment was more extensive than the sediment surface area. Increased oxygen supply through the extended interface could enhance the degradation rates of organic carbon and also change the pathways of degradation. Quantifying the relationship between the extended interface and mineralization rate and pathway requires more extensive study.

Biogenic Amine Formation in "Bez Sucuk," a Type of Turkish Traditional Fermented Sausage Produced with Different Meat: Fat Ratios

  • Cicek, Umran;Tokatli, Kader
    • Food Science of Animal Resources
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    • v.38 no.1
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    • pp.152-161
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    • 2018
  • This study aims to evaluate biogenic amine levels of bez sucuks (BS) produced with different meat:fat ratios. For this, three BS groups were manufactured with meat:fat ratios of 90:10 (BS10), 80:20 (BS20), and 70:30 (BS30). The pH and water activity values and biogenic amine amounts of sucuk samples were determined during processing and storage periods and the pH values of the initial mixtures of BS samples were in the range 5.51-5.74, decreasing to 4.72-4.94 by the $14^{th}$ day. The water activity values of BS samples showed significant decreases as a result of the drying stage and reached to range 0.913-0.935 on the $14^{th}$ day of processing (p<0.05). Although BS10 had the highest tyramine (434.12 mg/kg), histamine (5.69 mg/kg), cadaverine (12.48 mg/kg), putrescine (17.83 mg/kg), 2-phenylethylamine (15.43 mg/kg), and tryptamine (122.41 mg/kg) levels at the end of processing stage (p<0.05), spermine and spermidine levels did not differ between the BS samples due to their utilization of different meat:fat ratios (p>0.05). Similarly, the tryptamine (205.11 mg/kg), putrescine (43.57 mg/kg), and tyramine (766.23 mg/kg) levels of BS10 were higher than BS20 and BS30 samples at the end of storage (p<0.05). The results showed that BS10 with the highest meat ratio had the highest tryptamine, putrescine, and tyramine levels at the end of the processing and storage period.

Basic Study on the in-situ Biogenic Methane Generation from Low Grade Coal Bed (저품위 석탄의 원지반에서의 생물학적 메탄가스 생산에 관한 기초연구)

  • Wang, Fei;Jeon, Ji-Young;Lim, Hak-Sang;Yoon, Seok-Pyo
    • Journal of the Korea Organic Resources Recycling Association
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    • v.23 no.4
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    • pp.11-20
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    • 2015
  • In the present work, a basic study on the in-situ biogenic methane generation from low grade coal bed was conducted. Lignite from Indonesia was used as a sample feedstock. A series of BMP (Biochemical Methane Potential) tests were carried out under the different experimental conditions. Although nutrients and anaerobic digester sludge were added to the coal, the produced amount of methane was limited. Both temperature control and particle size reduction showed little effect on the increase of methane potential. When rice straw was added to lignite as an external carbon source, methane yield of 94.4~110.4 mL/g VS was obtained after 60 days of BMP test. The calorific value of lignite after BMP test decreased (4.5~12.1 %) as increasing the content of rice straw (12.5~50 wt % of lignite), implying that anaerobic digestion of rice straw led to partial degradation of lignite. Therefore, rice straw could be used as an external carbon source for the start-up of in-situ biogas generation from low grade coal bed.