• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.346-352
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• 2005

The chemical characteristics, enzymatic saccharification, and ethanol fermentation of autohydrolyzed lignocellulosic material that was exposed to steam explosion were investigated using bagasse as the sample. The effects of the steam explosion on the change in pH, organic acids production, degrees of polymerization and crystallinity of the cellulose component, and the amount of extractive components in the autohydrolyzated bagasse were examined. The steam explosion decreased the degree of polymerzation up to about 700 but increased the degree of crystallinity and the micelle width of the cellulose component in the bagasse. The steam explosion, at a pressure of 2.55 MPa for 3 mins, was the most effective for the delignification of bagasse. 40 g/L of glucose and 20 g/L of xylose were produced from 100 g/L of the autohydrolyzed bagasse by the enzymatic saccharification using mixed cellulases, acucelase and meicelase. The maximum ethanol concentration, 20 g/L, was obtained from the enzymatic hydrolyzate of 100 g/L of the autohydrolyzed bagasse by the ethanol fermentation using Pichia stipitis CBS 5773; the ethanol yield from sugars was 0.33 g/g sugars.

• KSBB Journal
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• v.4 no.1
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• pp.21-30
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• 1989

Lauryl alcohol was used as extracting solvent of ethanol, and its toxicity on the free cells or immobilized cells was tested. To increase ethanol productivity, extractive fermentation method combined with ethanol fermentation and ethanol recovery was applied to the immobilized batch and continuous fermenter. As the concentration of LaOH was increased, the lag phase became longer, but specific growth rate did not change greatly. And a cell entrapment technique could protect the yeast cells against both substrate inhibition and solvent toxicity. When the glucose concentration was 400 g/l and the LaOH/fermentation medium ratio was 4, total ethanol productivity increased with the enhancement of LaOH volume, and maximum productivity was 2.75 g/l.hr in the immobilized batch fermentation.

• Microbiology and Biotechnology Letters
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• v.26 no.1
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• pp.55-60
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• 1998

For an ideal extractive bioconversion in aqueous two-phase systems, the product has to be preferentially partitioned into the phase opposite to the one in which the biocatalyst is located. Partitioning behaviors of Lactobacillus helveticus IAM 11090 and lactic acid in aqueous two-phase systems composed a polycation, poly(ethylenimine) (PEI), and an uncharged polymer (hydroxyethyl)cellulose (HEC) were investigated. L. helveticus cells were preferentially partitioned to the HEC-rich top phase while about 85% of lactic acid was partitioned to the PEI-rich bottom phase. These results indicate that extraction of charged, low molecular weight products in an aqueous two-phase systems can be promoted by using an oppositely charged polymer as one of the phase-forming polymer. By the ideal partitioning of the cells and lactic acid, an aqueous PEI/HEC two-phase system can be used as a potential system for the extractive lactic acid fermentation of cheese whey.

• Journal of the Korean Society of Food Culture
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• v.17 no.4
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• pp.363-376
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• 2002

In order to establish the processing conditions for salt-fermented liquefaction of anchovy(Engrulis japonica), changes in the amino acid composition from oligopeptides during fermentation periods were analyzed. Experimental sample A: chopped whole anchovy, adding 20% water, heating at $50^{\circ}C$ for 9 hrs and then adding 10% NaCl. Sample B: chopped whole anchovy, adding 20% water, heating at $50^{\circ}C$ for 9 hrs and then adding 13% NaCl. Sample C: chopped whole anchovy adding 13% NaCl. Sample D: whole anchovy adding 17% NaCl. The total amino acids from oligopeptides in fermented liquefaction of anchovy increased in early fermentation period and reached highest level, and then they declined irregularly during fermentation. Their maximum amounts were just after heating at $50^{\circ}C$ for 9 hrs in sample A, after 15 days in sample B, and after 60 days in samples C and D. The fermented liquefaction of anchovy extracts were rich in glutamic acid, aspartic acid, proline, glycine, alanine, lysine and valine. However, the contents of most amino acids fluctuated by the experimental specimens and fermenting periods. Among them glutamic acid was the most abundant amino acid which was occupied $0.6{\sim}27.7%$(average 24.0%) in the content of total amino acids from oligopeptides. The contribution of the amino acid composition from oligopeptides to extractive nitrogen was occupying average 20.8 and 17.5% in rapid- and low salt-fermented liquefaction(sample A, B and C) and traditional fermented liquefaction(sample D), respectively.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.932-937
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• 2004

In situ extraction by organic solvent was studied in order to improve the recovery yield of hydrocarbon from the culture of Botryococcus braunii, a green colonial microalga. When the solvent mixture of octanol as an extractive solvent and n-octane as a biocompatible solvent was added to a two-phase column, the algal growth was seriously inhibited, even at a low concentration of polar octanol. Therefore, a two-stage cell-recycle extraction process was proposed to improve the contact area between the organic phase and the aqueous phase. The hydrocarbon recovery with in situ cell-recycle extraction showed a three-fold increase (57% of cell) in yield over that with two-phase extraction. In addition, over 60% of the hydrocarbon could be recovered without serious cell damage by downstream separation when this process was applied to the culture broth after batch fermentation.

• KSBB Journal
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• v.5 no.2
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• pp.95-100
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• 1990

Ethanol fermentations of inulin by K.fraglis in aqueous two-phase system of PEG/Dextran were performed not only to investigate the characteristics of partition of ethanol, sugar, and cell in the upper phase and the bottom phase but also to compare the fermentation properties with those of single phase system. In the range of 1 to 3 wt% of Dextran, ethanol fermentability and ethanol productivity reduced according to the increase of the molecular weight of PEG. But the cell yield and the cell productivity showed the opposite trend. In the region of 6 to 10 wt% of PEG, the increase of the concentration of PEG, caused the minute decrease of ethanol productivity but the remarkable augmentation of cell productivity. According to the increase of the molecular weight of PEG, the partition coefficient of inulin slightly decreased. But with the increment of the concentration of Dextran, the partition coefficient and the partition yield of inulin in the bottom Phase represented the trends of increase.

• Journal of the Korean Professional Engineers Association
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• v.29 no.2
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• pp.80-90
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• 1996

This research aimed at investigating the changes of volatile basic nitrogen, amino nitrogen and lipids during the fermentation of 6 month Anchovy cured under room temperature with various treatments(20, 30 and 40% salted) and examing the optimum condition of Anchovy sauce. The results are summerized as the V.B.N which increased with the curing period of anchovy from 14 mg% to 90～107mg% in 180 days curing at 20% salt level. Amino nitrogen in minced anchovy was higher than in whole anchovy during fermentation and the content of Extractive Nitrogen in the curing anchovy containing 20% of salt, kept the highest amount in 60 curing days. As a rule, minced anchovy showed more rapidly increased than whole anchovy. The lipid in curing anchovy containing 20% and 30% of salt has already been oxidized in 30 days while the lipid of anchovy cured with 40% salt prolonged the initial stage to 45 days. During fermentation, peroxide value and acid value showed constant increasing, while thiobarbituric acid began to decrease after 120 days curing. Among the non-polar lipids, linolenic acid, linoleic acid and erucic acid was decomposed by 24.5%, 22.2%, and 20.0%, respectively. It was noticed that the decomposition of polar lipid was retarded by higher salt content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.325-332
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• 1985

As a series of study for processing low salt fermented fish, this work was undertaken to investigate taste compounds of low sodium salt fermented anchovy and yellow corvenia comparing with conventional fermented fish ($20\%$ of salt contents) during the fermentation of 120 days at $25{\pm}3^{\circ}C$. The major amino acids in fermented anchovy at 60 day fermentation were lysine, alanine, leucine, valine, isoleucine, histidine, threonine and glycine, while those in fermented yellow corvenia at 90 day fermentation were lysine, leucine, alanine, valine, threonine, isoleucine, glutamic acid and methionine. These amino acids held $57\%$ of the total extractive nitrogen content for fermented anchovy and $41\%$ for fermented yellow corvenia, respectively. It was supposed from the results that principal taste compounds both for fermented anchovy and fermented yellow corvenia were free amino acids, and that nucleotides and their related compounds as well as total creatinine also played an assistant role. And also there was little difference between taste compounds of low salt fermented fish and those of conventional fermented fish irrespective of fish species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.725-729
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• 1999

In order to utilize large size anchor effectively, fermented and powdered anchovy seasoning for extractives was manufactured, Fermented anchovy saesoning was fabricated by adding $10\%$ koji of Aspergillus oryzae and mixing with $5\%$ Laminalia. The optimum fermentation temperature, humidity and time for manufacture of anchovy saesoning were $40^{\circ}C$, RH $80\%$ and 48 hrs, respectively. The amount of total free amino acids in anchovy seasoning with $5\%$ Lansinaria was 6,486.9 mg/100 g, while that of commercial product was 444.4 mg/100 g. The principal taste compounds in anchovy seasoning material were IMP and amino acids such as leucine, glutamic acid, histidine, alanine and valine. Extractive nitrogen and organoleptic quality of the extractives in anchovy seasoning packed in tea bag with air permeability, 100 $m^3/m^2/min$, were better than those of commercial product.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.4
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• pp.326-335
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• 1988

In order to increase the availability of filefish scrap, the ordinary and low salt sauce were prepared, and identified their taste compounds in their products. To process the filefish scrap sauce, chopped filefish scrap was mixed with koji, 25% brine, slat and glucose (25.0 : 65.0 : 12.5 : 7.0, w/w) and fermented at $25{\pm}4^{\circ}C$ for 120 days. The same process was also carried out to process the low salt sauce adding sorbitol, lactic acid and ethyl alcohol (7.0 : 0.7 : 9.0. w/w) instead of salt. While amino nitrogen and volatile basic nitrogen(VBN) of products were decreased, pH and reducing sugar were increased all alone the fermentation period. The major free amino acids of products at final stage of fermentation were glutamic acid, alanine, leucine, lysine and aspartic acid. And the contents of total amino acid in the ordinary and low salt sauce were 4126.6(mg/100m1 sauce), 4519.5(mg/100m1 sauce) after fermentation. Hypoxanthine was revealed as the major constituent among nucleotides and their related compounds through fermentation. Free amino acid-N in the filefish scrap sauces were from 56.3%(ordinary) to 60.7%(low salted) of extractive nitrogen. From the sensory evaluation, the quality of products from filefish scrap sauce were almost equal to sold soy sauce on the market.