• Journal of Microbiology
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• 제45권6호
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• pp.485-491
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• 2007

The effects of biological pretreatment on the Japanese red pine Pinus densiflora, was evaluated after exposure to three white rot fungi Ceriporia lacerata, Stereum hirsutum, and Polyporus brumalis. Change in chemical composition, structural modification, and their susceptibility to enzymatic saccharification in the degraded wood were analyzed. Of the three white rot fungi tested, S. hirsutum selectively degraded the lignin of this sortwood rather than the holocellulose component. After eight weeks of pretreatment with S. hirsutum, total weight loss was 10.7%, while lignin loss was the highest at 14.52% among the tested samples. However, holocellulose loss was lower at 7.81 % compared to those of C. lacerata and P. brumalis. Extracelluar enzymes from S. hirsutum showed higher activity of ligninase and lower activity of cellulase than those from other white rot fungi. Thus, total weight loss and changes in chemical composition of the Japanese red pine was well correlated with the enzyme activities related with lignin- and cellulose degradation in these fungi. Based on the data obtained from analysis of physical characterization of degraded wood by X-ray Diffractometry (XRD) and pore size distribution, S. hirsutum was considered as an effective potential fungus for biological pretreatment. In particular, the increase of available pore size of over 120 nm in pretreated wood powder with S. hirsutum made enzymes accessible for further enzymatic saccharification. When Japanese red pine chips treated with S. hirsutum were enzymatically saccharified using commercial enzymes (Cellulclast 1.5 L and Novozyme 188), sugar yield was greatly increased (21.01 %) compared to non-pre treated control samples, indicating that white rot fungus S. hirsutum provides an effective process in increasing sugar yield from woody biomass.

• 한국식품과학회지
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• 제48권2호
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• pp.97-103
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• 2016

본 연구는 메밀 알곡에 비해 유효성분이 많음에도 불구하고 식품학적 가치가 떨어져 폐기되고 있는 메밀껍질을 기능성 식품소재로 활용하기 위해 메밀껍질을 효소로 분해하여 수용성 식품섬유를 생산하고자 하였다. 메밀껍질을 효소를 이용하여 72시간 분해하여 수용성 식품섬유의 수율을 측정한 결과, 72시간 효소분해 후 셀룰로스 및 헤미셀룰로스 분획으로부터 얻은 수용성 식품섬유는 각각 60.5 g/kg, 123.7 g/kg이었으며, 총 수용성 식품섬유의 수율은 129.8 g/kg이었다. 겔 크로마토그래피에 의한 수용성 식품섬유의 분자량 추이를 측정한 결과, 분해 시간이 증가함에 따라 저분자의 피크가 크게 증가하여 효소 반응 시간이 증가할수록 분해가 진행되었다. 효소분해되지 않은 메밀껍질의 수용성 식품섬유에 비해 효소분해에 의해 생산된 식품섬유소의 산화방지 활성이 높게 나타났으며, 대조군에 비해 높은 포도당 및 담즙산 흡수 지연효과를 보였다. 따라서 메밀껍질로부터 생산된 수용성 식품섬유소는 산화방지를 비롯한 포도당 및 콜레스테롤의 흡수저하 효과를 가진 건강기능식품 소재로 사용될 수 있을 것으로 기대된다.

• 한국약용작물학회지
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• 제26권2호
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• pp.127-133
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• 2018

Background: The demand of recycling renewable agricultural by-products is increasing. Radiation breeding is a method used to improve saccharification efficiency. Thus, we investigated the effect of gamma ray irradiation on the pretreatment and enzymatic hydrolysis of the stalks of Senna tora, an important medicinal plants. Methods and Results: S. tora seeds were irradiated with gamma ray at doses of 100, 200, 300, and 400 Gy. In the pretreated biomass, glucan and lignin content were higher in the M1 ($1^{st}$ generations of irradiation) S. tora stalks than in the M2 ($2^{nd}$ generations of irradiation) stalks, this can be explained by the higher degradation rate in M1. After oxalic acid pretreatment, the concentration of total phenolic compounds (TPCs) in the hydrolysate increased in the gamma ray treated seeds. The highest relative increase rate in crystallinity in the pretreated biomass was observed in M1-400 Gy and M2-100 Gy. The cellulose conversion rate was higher in M1 than in M2, except for 200 Gy. Conclusions: Gamma ray irradiation at an appropriate dose can be used to improve the efficiency of pretreatment and enzymatic hydrolysis, thereby increasing biomass availability.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.84-92
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• 1999

The rumen microbial ecosystem is coming to be recognized as a rich alternative source of genes for industrially useful enzymes. Recent advances in biotechnology are enabling development of novel strategies for effective delivery and enhancement of these gene products. One particularly promising avenue for industrial application of rumen enzymes is as feed supplements for nonruminant and ruminant animal diets. Increasing competition in the livestock industry has forced producers to cut costs by adopting new technologies aimed at increasing production efficiency. Cellulases, xylanases, ${\beta}$-glucanases, pectinases, and phytases have been shown to increase the efficiency of feedstuff utilization (e.g., degradation of cellulose, xylan and ${\beta}$-glucan) and to decrease pollutants (e.g., phytic acid). These enzymes enhance the availability of feed components to the animal and eliminate some of their naturally occurring antinutritional effects. In the past, the cost and inconvenience of enzyme production and delivery has hampered widespread application of this promising technology. Over the last decade, however, advances in recombinant DNA technology have significantly improved microbial production systems. Novel strategies for delivery and enhancement of genes and gene products from the rumen include expression of seed proteins, oleosin proteins in canola and transgenic animals secreting digestive enzymes from the pancreas. Thus, the biotechnological framework is in place to achieve substantial improvements in animal production through enzyme supplementation. On the other hand, the rumen ecosystem provides ongoing enrichment and natural selection of microbes adapted to specific conditions, and represents a virtually untapped resource of novel products such as enzymes, detoxificants and antibiotics.

• Journal of Applied Biological Chemistry
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• 제59권3호
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• pp.215-220
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• 2016

식물의 이차생장의 결과로 생산되는 바이오매스의 대부분은 식물의 이차세포벽에 축적된다. 식물의 이차세포벽은 크게 셀룰로스, 헤미셀룰로스, 리그닌이라는 3가지 물질로 구성되며 이들 중 페놀성 복합 화학 물질인 리그닌은 셀룰로스나 헤미셀룰로스와 달리 알코올 발효과정의 저해 물질로이다. 따라서, 식물의 이차세포벽 생합성의 과정을 조절함으로 전체 바이오매스의 생산량과 조성을 바이오 에너지 생산을 위해 최적 조건으로 조절함으로써 바이오 에탄올 생산을 최대화할 수 있을 것이다. 본 연구에서는 애기장대 유래 MYB7 유전자를 CaMV35S 프로모터 조절 하에서 과별현되게 한 식물체와 식물의 전사조절에서 하위 특정 유전자의 발현을 저해시키는 것으로 잘 알려진 SRDX 융합 단백질 즉, MYB7-SRDX 과발현체를 제작하여 그 특성을 조사하였다. 그 결과 MYB7 전사조절 인자가 리그닌의 생합성을 억제 조절한다는 결과를 관찰하였다. 이는 MYB7 전사조절인자를 이용하면 바이오 에탄올 발효과정에 저해 물질로 작용하는 리그닌을 경감시킬 수 있는 기초 자료로 사용할 수 있을 것이다.

• Preventive Nutrition and Food Science
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• 제15권1호
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• pp.57-66
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• 2010

Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at $121^{\circ}C$. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 mg/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1728-1733
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• 2006

A Gram-negative, strictly aerobic, nonmotile, and nonspore-forming bacterial strain, designated $T5-12^T$, was isolated from compost and characterized using a polyphasic taxonomical approach. The isolate was positive for catalase and oxidase tests. It could degrade DNA, but was negative for degradation of macromolecules such as casein, collagen, starch, chitin, cellulose, and xylan. The DNA G+C content was 36.0 mol%. The predominant isoprenoid quinone was menaquinone 7 (MK-7). The major fatty acids were $iso-C_{15:0}$ (45.6%), $iso-C_{17:0}$ 3OH (17.2%), and summed feature 4 ($C_{16:0}\;{\omega}7c$ and/or $iso-C_{15:0}$ 2OH, 14.9%). Comparative 16S rRNA gene sequence analysis showed that strain $T5-12^T$ fell within the radiation of the cluster comprising members of the genus Sphingobacterium. Strain $T5-12^T$ exhibited lower than 94% of 16S rRNA gene sequence similarity with respect to the type strains of recognized Sphingobacterium species. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain $T5-12^T$ ($=KCTC\;12578^T=LMG\;23401^T=CCUG\;52467^T$) should be classified in the genus Sphingobacterium as the type strain of a novel species, for which the name Sphingobacterium composti sp. novo is proposed.

• Asian-Australasian Journal of Animal Sciences
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• 제20권6호
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• pp.887-893
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• 2007

Influences of forage DM and addition of cane molasses on silage characteristics of berseem (Trifolium alexandrium) and lucerne (Medicago sativa) and their ruminal digestion kinetics in Nili buffaloes were studied. Berseem and lucerne fodders (at one tenth bloom) were ensiled with wheat straw in laboratory silos to achieve 20, 30, 40% forage DM and without wheat straw (control); each forage DM level was supplemented with 2, 4 and 6% of cane molasses at ensiling. The pH and lactic acid contents of berseem and lucerne silages were affected by both forage DM and addition of molasses. Dry matter, CP and true protein (TP) of berseem and lucerne silages were affected by forage DM at ensiling but were not affected by the addition of cane molasses. Higher DM, CP and TP losses were observed when berseem and lucerne fodders were ensiled either without wheat straw or with wheat straw to achieve 20% and 40% forage DM at ensiling compared with 30% DM at ensiling. Fiber fractions (NDF, ADF, hemicellulose and cellulose) of berseem silage and lucerne silage were significantly increased with increasing forage DM at ensiling. Addition of cane molasses did not affect the DM, CP, TP and fiber fractions of both berseem and lucerne silages. Berseem and lucerne ensiled at 30% DM with 2% cane molasses were screened for comparative ruminal digestion kinetics with their respective fodders. Addition of wheat straw to berseem or lucerne fodder at ensiling depressed DM and NDF ruminal degradability. However, ruminal lag time, rate of degradation and extent of digestion of silages were similar to their respective fodders. In conclusion, berseem and lucerne could be ensiled with wheat straw to increase their DM to 30% along with 2% molasses for buffaloes.

• 한국미생물·생명공학회지
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• 제4권3호
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• pp.105-110
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• 1976

곰팡이를 이용하여 섬유소분해효소를 생산할 목적으로 전국각처에서 수집한 102종의 시료로부터 총 221주의 곰팡이를 분리하였다. 이들 분리균주의 섬유소분해능을 여과 지붕괴법 ？ 액화법 및 cup method로서 1차 36균주를 선별하였고 1차 선별된 균주를 탄소원을 변경하여 배양한뒤 활성을 추정하여 2차로 15균주를 선별하였다. 15균주를 개선된 배지에서 배양한뒤 $C_1$, $C_{x}$ 및 filter paper-activity을 측정하여 최종적으로 $C_1$및 $C_{x}$ -Cellulase의 활성이 강한 균주인 Aspergillus sp. strain No. AS-9, Penicillium sp. strain No. KI-1-2 Trichoderma sp. strain No. KI-7-2, KI-7-5, 및 KI-4-IB을 선별하였다. 이상 최종적으로 선별된 균주중의 strain No. KI-4-1-1B 조효소액으로 ammonia 처리볏짚을 당화시킬 때 24시간 작용으로 26%가 당화되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1113-1120
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• 2000

Productivity, nutrient contents, in vitro gas production and in sacco degradability of different fractions and whole OPF were determined to assess the feeding value of OPF as a ruminant feed. An in vivo digestibility trial was also carried out using goat. Freshly harvested OPF was randomly collected, partitioned and weighed. An OPF from 21 years older palm weighed 13.4 kg and the annual fresh matter yield of petiole, leaflet and midrib was 46.5, 11.8 and 3.4 ton/ha, respectively. Leaflet contained 439, 926, 698, 501, 168, 196, 748 and 52 (g/kg) of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose (CE), hemicellulose (HC), total carbohydrate (TC) and non fiber carbohydrate (NFC), respectively. Petiole contained lower (p<0.01) DM, CP and EE contents than leaflet. Organic matter, CE and TC contents were higher (p<0.01) in petiole compared to leaflet. Silica and lignin contents were highest (p<0.01) in midrib followed by leaflet, whole OPF and least in petiole. The Ca, P, Na, K and Mg contents (g/100 g DM) of leaflet were 0.529, 0.182, 0.039, 0.876, and 0.168, respectively. In vitro DM digestibility (g/100 g) at 48 h of leaflet, petiole and midrib was 32.7, 38.7 and 30.2, respectively. The in sacco DM degradation (g/100 g) at 48 h of leaflet was higher than that of whole OPF, petiole and midrib. The in vivo digestibility of DM, OM, CP and ADF of whole OPF was 52, 56, 43 and 26%, respectively. It can be concluded that leaflet is the most nutritious fraction of OPF and midrib is the least. The nutrient content and digestibility of the whole OPF showed that OPF could be an alternative roughage source for ruminant diets.