• Title/Summary/Keyword: natural cellulose

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Purification and Characterization of $\beta$-Cyclodextrin Glucanotransferase Excreted by Bacillus firmus var. aikalophilus. (호알칼리성 Bacillus firmus가 생산하는 $\beta$-Cyclodextrin Glucanotransferase의 정제 및 효소반응 특성)

  • Shin, Hyun-Dong;Kim, Chan;Lee, Yong-Hyun
    • Microbiology and Biotechnology Letters
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    • v.26 no.4
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    • pp.323-330
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    • 1998
  • Cyclodextrin glucanotransferase (CGTase) was purified from the culture broth of the Bacillus firmus var. alkalophilus, using ultrafiltration, starch adsorption/desorption, ion-exchange chromatography on DEAE-cellulose and gel filtration on Sephacryl HR-100. The molecular weight of the purified enzyme was determined as 77,000 by SDS-PAGE. The optimum pH and temperature for the CD synthesis were 6.0 and 5$0^{\circ}C$, respectively. The activity of this enzyme was stably kept at the range of pH 6.0~9.5 and up to 5$0^{\circ}C$. However, in the presence of $Ca^{2+}$, the optimum temperature for CD synthesis was shifted 55~6$0^{\circ}C$ and this enzyme was stable up to 6$0^{\circ}C$ because of the stabilizing effect of $Ca^{2+}$. The purified CGTase produced CDs with high conversion yields of 45~51% from sweet potato starch, com starch and amylopectin as substrate, especially, and the product ratio of $\beta$-CD to ${\gamma}$-CD was obtained at range of from 5.8:1 to 8.4:1 according to the kind of substrate. The purified enzyme produced mainly $\beta$-CD without accumulation of $\alpha$-CD during enzyme reaction using various starches as the substrate, indicating that the purified enzyme is the typical $\beta$-CGTase. The purified CGTase produced 25 g/l of CDs from 5.0% (w/v) liquefied com starch and the conversion yield of CDs was 50%, and the content of $\beta$-CD was 84% of total CDs after 8 hours under the optimum reaction condition.ion.

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Immunostimulating Activity and Characterization of Polysaccharides from Mycelium of Phellinus linteus

  • Lee, Jae Hoon;Soo Muk Cho;Kyung Sik Song;Sang Bae Han;Hwan Mook Kim;Nam Doo Hong;Ick Dong Yoo
    • Journal of Microbiology and Biotechnology
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    • v.6 no.3
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    • pp.213-218
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    • 1996
  • Hot-water extract, Fr. 1, of Phellinus linteus mycelium was fractionated into Fr. 2, 3, 4, and 5 by the difference of solubility in ethanol. The polysaccharide fractions were studied for their immunostimulating activity on in vitro T-independent polyc1onal antibody response to trinitrophenyl-haptened SRBC (sheep red blood cell). The Fr. 4 with the highest immunostimulating activity was subjected to DEAE-cellulose ion exchange chromatography and gave five fractions, 4-I, II, III, IV, and V. The in vitro immunostimulating assay of the five fractions showed that 4-I and 4-III had a similar activity to that of LPS but the other fractions had low activity. By analyses of chemical composition and HPLC, all fractions obtained were found to be heteropolysaccharide-protein complex. The molecular weights ranged from 9, 000 to 15, 000. Sugar analyses showed that glucose, galactose, mannose, arabinose, and xylose were main component. Uronic acid and amino sugar were also detected in the fractions. It should be noted that the molecular weight (15, 000) of 4-III was very small and the structure of 4-III may be different from the known immunostimulating branched $\beta$-(1longrightarrow3)-glucan.

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Effect of carbonization temperature and chemical pre-treatment on the thermal change and fiber morphology of kenaf-based carbon fibers

  • Kim, Jin-Myung;Song, In-Seong;Cho, Dong-Hwan;Hong, Ik-Pyo
    • Carbon letters
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    • v.12 no.3
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    • pp.131-137
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    • 2011
  • Kenaf fibers, cellulose-based natural fibers, were used as precursor for preparing kenafbased carbon fibers. The effects of carbonization temperature ($700^{\circ}C$ to $1100^{\circ}C$) and chemical pre-treatment (NaOH and $NH_4Cl$) at various concentrations on the thermal change, chemical composition and fiber morphology of kenaf-based carbon fibers were investigated. Remarkable weight loss and longitudinal shrinkage were found to occur during the thermal conversion from kenaf precursor to kenaf-based carbon fiber, depending on the carbonization temperature. It was noted that the alkali pre-treatment of kenaf with NaOH played a role in reducing the weight loss and the longitudinal shrinkage and also in increasing the carbon content of kenaf-based carbon fibers. The number and size of the cells and the fiber diameter were reduced with increasing carbonization temperature. Morphological observations implied that the micrometer-sized cells were combined or fused and then re-organized with the neighboring cells during the carbonization process. By the pre-treatment of kenaf with 10 and 15 wt% NaOH solutions and the subsequent carbonization process, the inner cells completely disappeared through the transverse direction of the kenaf fiber, resulting in the fiber densification. It was noticeable that the alkali pre-treatment of the kenaf fibers prior to carbonization contributed to the forming of kenaf-based carbon fibers.

Industrial Applications of Rumen Microbes - Review -

  • Cheng, K.J.;Lee, S.S.;Bae, H.D.;Ha, J.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.1
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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.

An Electron-Microscopical Study of Cellulase Activity on Germinating Endosperm of Cannabis saiva L. (발아중인 대마 배유조직의 Cellulase 활동에 관한 전자현미경적 연구)

  • Kim, Young-Hee;Kim, Eun-Soo
    • Applied Microscopy
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    • v.24 no.3
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    • pp.67-77
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    • 1994
  • Storage material of endosperm cells digested by various enzymes should be transported to the embryo. At this time, the cellulose of the endosperm cell wall is guessed to be hydrolyzed by the cellulase enabling to transfer the storage material from the endosperm cells to the embryo. Therefore, this study has been carried out to investigate the ultrastructure of endosperm and the localization of the cellase activity on Cannabis sativa L. during germination. Endosperm cells contain a large number of lipid bodies and protein bodies with globoids as the storage material. During gemination they are gradually degenerated, however, the former almost remain until the cells are completely digested. Electron-microscopical reaction products of cellulase on endosperm cells are present. The closer the embryo, the more amount of reaction products on the endosperm cell wall are appeared.

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Decentralized Composting of Garbage in a Small Composter for Dwelling House II. Changes in Microbial Flora in laboratory Composting of Household Garbage in a small Bin (가정용 소형 퇴비화 용기에 의한 부엌쓰레기의 분산식 퇴비화 II. 실험실 조건에 있어서 미생물상의 변동)

  • Lee, Yon;Joo, Woo-Hong;Seo, Jeoung-Yoon
    • Korean Journal of Environmental Agriculture
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    • v.13 no.3
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    • pp.338-345
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    • 1994
  • In the course of developing a small composter for dwelling house, we designed two different small bins; one is insullated (type 1) and the other uninsullated (type 2). Several interesting results were abtained from the study using these bins for garbage composting in winter, spring and summer. Changes in microbial number were very similar to those observed in the general composting process. However, microbial flora was relatively simple. The genera Streptomyces and Nocardia of actinomycetes and the genera Aspergillus, Penicillium, Mucor, Absidia, Rhizopus of hypomycetes was observed from the composted materials. Thermophiles secreted most of the ${\alpha}-amylase$ secreted in winter but mesophilic actinomycetes did in summer. The amount of secreted protease was much lower in winter than in summer. Lipases were secreted more by mesophiles than thermophiles. Only Aspergillus of hypomycetes was observed to degrade cellulose. Generally, the appearance of enzyme producing microorganisms increased in summer than in the other seasons. In the point of seasonal increase of temperature and changes in microbial flora, the number of microorganisms was higher in summer or spring than in winter.

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The Preparation of Mask-pack Sheet Blended with Styela clava tunics and Natural Polymer (미더덕껍질과 천연고분자 혼합물을 이용한 마스크팩시트의 제조방법)

  • Yun, Woobin;Lee, Yechan;Kim, Dasom;Kim, Jieun;Sung, Jieun;Lee, Hyunah;Son, Hongju;Hwang, Daeyoun;Jung, Youngjin
    • Textile Coloration and Finishing
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    • v.29 no.1
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    • pp.45-54
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    • 2017
  • Ultraviolet radiation have much influenced with a deep wrinkles, roughness, laxity of skin damage and pigmentation through oxidative stress and oxidative photo-damage. This study investigates the functional properties of hydrogel facial mask sheets made from agar, Styela clava tunics and Broussonetia papyrifera tunics. The skin of S. clava is covered with a hard cellulose containing glycoprotein, glycosaminoglycan and chondroitin sulfate. B. papyrifera is better known as Paper mulberry. It contains kazinol which serves as a tyrosinase inhibitor and skin whitening agent. The tensile strength of facial mask sheet was measured by universal testing machine, and the water absorption and moisture permeability of facial mask sheet were measured by dryer. Additionally, the DPPH assay and MTT assay were conducted for anti-oxidative activity and cytotoxicity of facial mask sheet. The whitening effect of the facial mask sheet was measured by tyrosinase inhibitor assay. These tests showed that the three ingredients are suitable cosmetic materials. The results reveal that they produce a high quality hydrogel facial mask sheet when the membrane contains 1%(W/V) of agar, 0.1%(W/V) of B. papyrifera tunics and 0.05%(W/V) of S. clava tunics.

Preparation and Mechnical Properties of Biodegradable Plastic Natural Fiber Composite (생분해성 플라스틱 천연Fiber 복합체의 물리적 특성)

  • Lee, Dong-Hyun;Kim, Sung-Tae;Kim, Dong-Gye;Kim, Sang-Gu;Park, Byung-Wok
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2011.03a
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    • pp.79-79
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    • 2011
  • 최근 플라스틱 제품의 사용후 폐기에서 발생 되는 환경적인 문제점들이 대두 되고 있는 가운데, 이러한 제품에 대한 친환경적인 재료 설계에 대한 요구가 거세지고 있는 실정으로 플라스틱 업계의 사활이 걸릴 정도의 중요한 문제로 부각되고 있다. 본 연구에서는 이러한 플라스틱 제품의 치명적인 환경적인 문제점을 극복하고자, Matrix 물질이 되는 플라스틱에서 부터 친 환경적인 생분해성 수지를 사용하면서, 물성의 강화제로써 천연물 유래의 여러 종류의 섬유를 사용하고자 하였다.가장 보편화된 생분해성 플라스틱인 지방족 폴리에스테르 계통의 생분해성 수지와 Polylactic acid에 대해 검토를 하였다. 지방족 폴리에스테르 의 경우는 기존 플라스틱 제품과 비교해서 유연하고, 신장율이 높고, PLA 대비 내열 사용한계 온도도 높아서 물성적인 측면에서 상당한 장점을 가지고는 있으나 가격이 매우 고가이므로, 기존 플라스틱을 대체하는 것에는 문제점이 있다. 반면 PLA의 경우 지방족 폴리에스테르 대비 절반 이하의 가격이고 기계적 강도 또한 매우 높기 때문에 기존의 플라스틱을 대체할 수 있는 가장 유력한 물질로 대두 되고 있으나, 사출물과 같은 충격이 요구되는 제품에 있어서는 PLA 고유의 약한 취성이 가장 큰 단점으로 지적되고 있다. 본 연구에서는 이러한 PLA를 기반으로 PLA의 장점이 기계적 강성을 유지하면서, 취성을 보완하기 위해 PBS를 혼합 할 수 있는 기술을 개발하였으며, 또한 원재료의 Cost를 줄이고, PBS 혼합에 따른 PLA의 기계적 강도 감소를 보완하기 위해 천연물 유래의 Wood fiber, Starch, Bamboo fiber, Cellulose fiber, Paper fiber 와 같은 각종 천연 Filler를 사용하여 기계적 기계적 강도 감소를 최소화 하였다.

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The Effective Preparation of Protopanaxadiol Saponin Enriched Fraction from Ginseng using the Ultrafiltration

  • Seol, Su Yeon;Kim, Bo Ram;Hong, Se Chul;Yoo, Ji Hyun;Lee, Kun Hee;Lee, Ho Joo;Park, Jong Dae;Pyo, Mi Kyung
    • Natural Product Sciences
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    • v.20 no.1
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    • pp.58-64
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    • 2014
  • In this study, edible protopanaxadiol saponin enriched fraction were prepared by ultrafiltration (UF). Ginseng extract was prepared from mixtures of ginseng main root and rootlet (root: rootlet = 4 : 6). UF system was used the four-piston Diaphragm pump equipped with 5 kDa pore size Hydrosart Cassette made by regenerated cellulose acetate (CA) or 3 kDa pore size Hollow Fiber cartridge made by polyethersulfone (PES). Total ginsenoside contents of concentrated fraction by UF system was found to higher, compared to before those of untreated method. Especially, processing of UF showed the increase of PPD-type ginsenoside, while PPT-type ginsenoside was gradually decreased by both 3 kDa and 5 kDa membrane. After removal of 80% water by the 5 kDa Hydrosart Cassette and by 3 kDa Hollow Fiber cartridge, ginsenoside Rb1 content was higher 37.2 mg/g and 25.3 mg/g than 20.8 mg/g in untreated process. The ratio of Rb1 to Rg1 (Rb1/Rg1) and PPD- to PPT- type ginsenoside (PPD/PPT) were higher in inner fluid of ginseng extract after UF by 3 kDa cartridge (47.1 and 23.5, respectively) and 5 kDa Cassette (25.3 and 11.9, respectively) than those of before UF (5.7 and 3.7, respectively). PPD-type ginsenoside enriched fraction by UF system could be developed as a new ginseng material in food and cosmetic industrials.

Screening and Characterization of an Enzyme with ${\beta}-Glucosidase$ Activity from Environmental DNA

  • Kim, Soo-Jin;Lee, Chang-Muk;Kim, Min-Young;Yeo, Yun-Soo;Yoon, Sang-Hong;Kang, Han-Cheol;Koo, Bon-Sung
    • Journal of Microbiology and Biotechnology
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    • v.17 no.6
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    • pp.905-912
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    • 2007
  • A novel ${\beta}-glucosidase$ gene, bglA, was isolated from uncultured soil bacteria and characterized. Using genomic libraries constructed from soil DNA, a gene encoding a protein that hydrolyzes a fluorogenic analog of cellulose, 4-methylumbelliferyl ${\beta}-D-cellobioside$ (MUC), was isolated using a microtiter plate assay. The gene, bglA, was sequenced using a shotgun approach, and expressed in E. coli. The deduced 55-kDa amino acid sequence for bglA showed a 56% identity with the family 1 glycosyl hydrolase Chloroflexus aurantiacus. BglA included two conserved family 1 glycosyl hydrolase regions. When using $p-nitrophenyl-{\beta}-D-glucoside$ (pNPG) as the substrate, the maximum activity of the purified ${\beta}-glucosidase$ exhibited at pH 6.5 and $55^{\circ}C$, and was enhanced in the presence of $Mn^{2+}$. The $K_m\;and\;V_{max}$ values for the purified enzyme with pNPG were 0.16 mM and $19.10{\mu}mol/min$, respectively. The purified BglA enzyme hydrolyzed both pNPG and $p-nitrophenyl-{\beta}-D-fucoside$. The enzyme also exhibited substantial glycosyl hydrolase activities with natural glycosyl substrates, such as sophorose, cellobiose, cellotriose, cellotetraose, and cellopentaose, yet low hydrolytic activities with gentiobiose, salicin, and arbutin. Moreover, BglA was able to convert the major ginsenoside $Rb_1$ into the pharmaceutically active minor ginsenoside Rd within 24 h.