• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.1-7
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• 2013

Ionic liquids (ILs) have been widely recognized as environmentally benign solvents. Their unique properties, including negligible vapor pressure, non-flammability, a wide liquid range and their tunable physicochemical properties by proper selection of cations and anions, make them attractive green solvents in a variety of fields such as organic synthesis/catalysis, extraction/ separation, and electrochemistry, amongst others. In this paper, the recent technological developments and their prospects in the application of ILs in microbiology and biochemical engineering, including enzymatic reactions, protein folding/refolding and biomass dissolution, are discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.4
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• pp.445-453
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• 2016

Seahorse Hippocampus abdominalis a marine teleost fish, has long been used as one of the essential materials in traditional Chinese medicine. However, the uses of seahorse have been limited due to its high cost, despite its beneficial biological activities. Seahorse has not been widely explored for its biofunctional properties and active components. In the present study, the enzymatic hydrolysates of seahorse were prepared by using two digestive enzymes (trypsin and pepsin) and five food grade enzymes (neutrase, protamex, alcalase, kojizyme, and flavourzyme). The enzymatic hydrolysates indicated higher hydrolysis yields than its water extract. Among them, the distilled water-pepsin hydrolysate (DP) which was obtained by distilled water extraction followed by pepsin hydrolysis, showed the highest yield and protein content as well as the highest alkyl radical scavenging activity. Also, it provided protective effects against oxidative stress induced by AAPH in vero cell and zebrafish. Further fractionation based on the molecular weight was carried out to identify it’s active components, and < 5 kDa (less than 5 kDa) molecular weight fraction was confirmed to have the highest antioxidant activity. In conclusion, this study suggests that DP of seahorse has antioxidant properties, and might be a novel and useful material from the marine origin for healthy functional foods and cosmetics.

• Korean Journal of Food Science and Technology
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• v.4 no.4
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• pp.300-308
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• 1972

For the purpose of utilizing agricultural waste products for animal feeds, chemical analysis of some important agricultural wastes in Korea and enzymatic hydrolysis of rice hull were undertaken and summarized as follows: 1) Rice hull and straws of rice, barley and wheat were analyzed for their proximate principles and carbohydrate composition. 2) A strain of Aspergillus niger was selected as having the highest productivity of rice hull decomposing activity among many species of molds. The optimum conditions for the culture on washed wheat bran were. 3 days of culture period, 55% moisture content and neutral pH and one hour was proper for the extraction of enzymes. 3) The extent of hydrolysis of xylan and rice hull by a crude enzyme preparation from this strain was 63% and 7%, respectively, and the optimum pH for its activity was 4.0 and 4.5, respectively. 4) Enzymatic hydrolysis of rice hull was generally suppressed by gamma-ray irradiation ($0.5{\sim}5\;Mrad$, in dry state), but the effect was less by irradiation in wet state.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.732-738
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• 2009

An acidic polygalacturonase (PG) from Aspergillus kawachii was produced by solid state fermentation employing a polyurethane foam support. The conditions used for the production of acidic PG were particle size of support (0.6 or 500 $mm^3$) and fermentation time. From the factors studied, the particle size had important influence on enzyme production. The best conditions for acidic PG production were $0.6\;mm^3$ particle size, 18 hr at $30^{\circ}C$ and initial pH of 5.0. In addition, pectin was extracted from citrus pomaces (grapefruit, lime, and tangerine) by acidic PG at $50^{\circ}C$ for 24 hr with citric acid solution. Infrared spectroscopy showed that lime pomace had more high-methoxylated (65%) endogenous pectin than was obtained than from grapefruit or tangerine pomaces. The enzymatically extracted pectin yield in dry basis (d.b.) for grapefruit and lime pectins were 6.95 and 4.25%, respectively. The citric acid solution alone also contributed to pectin extraction from citrus pomaces (7-9%, d.b.). Limited pectin extraction by acidic PG from tangerine pomace was most likely due to the presence of low-methoxylated endogenous pectin. The enzymatic method for pectin extraction using acidic PG from A. kawachii is a promising technique for releasing highly polymerized pectic substances from high-methoxylated lime or grapefruit pomaces.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.2
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• pp.95-102
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• 2023

Despite the easing of social distancing, demand for non-face-to-face services continues to rise. Recently, the EU is pursuing a comprehensive plastic use reduction by expanding the scope of plastic use regulations for packaging plastics according to the New Cyclical Economy Action Plan(NCEAP). In response to this trend, the packaging industry is moving away from conventional non-degradable/petroleum-based plastics and conducting research on packaging materials using biodegradable plastics such as PLA(Poly Lactic Acid), PBAT(Poly Butylene Adipate-co-butylene Terephthalate). On the other hand, ginkgo leaves occur in large quantities in Korea and act as a cause of slip accidents and flooding. In this study, a method to utilize ginkgo biloba leaf as a new alternative biomass resource was proposed by producing lactic acid through pretreatment, enzymatic saccharification, and fermentation processes. For the efficiency of lactic acid production, a comparative analysis of lignin content from before and after browning was performed. In addition, the degree of glucan extraction was evaluated by applying a pretreatment method using three catalysts: hot water, sulfuric acid, and sodium hydroxide. It is difficult to expect high production of lactic acid with single process. Therefore, an integrated process operation using both the pretreated hydrolyzate and the residual solid enzymatic saccharification solution must necessarily be applied.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.712-715
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• 2001

A new combined method including the enzymatic hydrolysis of $\beta$-cyclodextrin ($\beta$-CD) and solvent extraction fo cholesterol from the hydrolyzed mixture was developed to recover cholesterol from a $\beta$-CD-cholesterol complex prepared from dairy products, such as cream, milk, and cheese. Cyclomaltodextrinase (cyclomatodextrin dextrin hydrolase, EC 3.2.1.54, DCase_ prepared form alkalophilic Bacillus sp. KJ 133 hydrolyzed the $\beta$-DC of the $\beta$-CD-cholesterol complex, and then, free cholesterol was efficiently extracted from the hydrolyzed mixture by a nonpolar solvent such as ethyl acetate. To increase the stability of free CDase, immobilized CDase was developed using sodium alginate as a carrier. The immobilized CDase showed a high recovery yield of cholesterol in a time-dependent manner compared to the free CDase. A gas chromatography analysis showed that more than 70% of cholesterol was recovered from the $\beta$-DC-cholesterol complex of cream by the immobilized CDase, whereas only 3% and 29% of cholesterol were recovered when the solvent extraction and free CDase treatment were used, respectively. The cholesterol recovered can be used as a raw material for steroid synthesis. Furthermore, this method can be an efficient way to recover cholesterol or other organic compounds that are bound in a $\beta$ -DC-cholesterol or -organic compound complex.

• KSBB Journal
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• v.25 no.3
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• pp.223-229
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• 2010

Fucoidans, polysaccharides that are composed of fucose, uronic acids, galactose and xylose, are one of the main constituents of brown seaweeds. For the past decade algal fucoidans have been extensively studied due to their biological activities including anticoagulant, antiinflammatory, antitumor, contraceptive and antiviral activities. Even though fucoidan is known as a highly functionality derivative, its industrial applications have been limited because of low inclusion efficiency and high cost of manufacturing. Furthermore the sea-weed smell of fucoidan has been a limiting factor for the application especially in food and cosmetic area. The potential application of various extraction technology and deodorization of sea-weed smell is highly required for a wider application of fucoidan. As an alternative extraction process, enzymatic hydrolysis process or ultra-high pressure treatment has been investigated for the improvement of production yield and bioefficacy of fucoidan. More intensive research on the fucoidan production technology and its application in nutraceutical and cosmoceutical area is needed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.1
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• pp.1-10
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• 2014

Xylanase (X) derived from Aurreobasidium pullulans and laccase-mediator system (LM) using Trichophyton sp. LKY-7 laccase (TrL) and N-hydroxy-2-pyridone analogue (NHP) as a mediator were applied in hardwood kraft pulp (HwKP) bleaching. The individual and the synergistic effects of X and LM stage were investigated in the enzymatic bleaching of HwKP. Also, the effects of subsequent alkaline extraction (E) and alkaline/hydrogen peroxide treatment (P) were examined. In X or LM treatment alone, an appreciable bleaching effect of HwKP was not observed, whereas subsequent E or P stage enhanced the increase of brightness and the decrease of kappa number. Especially, P stage significantly enhanced the bleaching effect of pulp. Bleaching of HwKP with XLM sequentially gave significantly higher pulp brightness and lower kappa number than that obtained after the treatment of HwKP with X+LM simultaneously. When HwKP was sequentially treated with XLM followed by P stage, the brightness increased by about 11% ISO and the kappa number decreased by about 3.6 in comparison with the initial pulp. Xylanase and laccase were strongly inactivated by NHP both in the absence and the presence of pulp.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.413-418
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• 1996

Two methods were used to extract pectin from apple cell wall by enzyme(Hemicellulase) and by acid. Hemicellulase was used to extract high functional pectin with higher degree of polymerization. The yield of weight of pectin by hemicellulase treatment was slightly higher than that by acid treatment. The optimal condition for extraction was accomplished by providing 1.5 grams of Hemicellulase at 38$^{\circ}C$ for 24 hours. The comparison of the pectin purity and the yield of extracts by the portion of galacturonic acid between two methods showed that the purity of pectin extracted by enzymatic method was lower than that by acid treatment.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.890-896
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• 2018

The aim of this study was to determine volatile flavor compounds in Shingo pear juice. Volatile flavor compounds were analyzed using solid-phase micro-extraction (SPME) - gas chromatography-mass spectrometry (GC-MS). The effect of inorganic salts solution on the extraction ability of the SPME fiber was treated by adding saturated $CaCl_2$ solution at the ratio of 1:20 (v/v) after 0, 60, 120 min of preparing pear juice, respectively. As a result, a total of 22 volatile compounds were identified in Shingo pear juice. Ethyl acetate was found to be the most abundant volatile compound ($13.36{\sim}19.61{\mu}g/kg$), followed in order by hexanal, ethyl hexanoate, ethyl 3-(methylthio)-2-propenoate, ethyl octanoate and 2-hexenal. Total contents of volatile flavor compounds were $31.07{\mu}g/kg$ (control), $40.93{\mu}g/kg$ (0 min), $27.62{\mu}g/kg$ (60 min) and $26.32{\mu}g/kg$ (120 min). This result indicated that the addition of saline solutions could inhibit the enzymatic reaction of volatile flavor compounds effectively when treated as soon as juice preparation.