미생물의 키틴분해에 대한 연쇄이화작용

박제권 한국키틴키토산학회 1999 한국키틴키토산학회지 Vol.4 No.2

본 연구에서는 폐수 및 정수처리에 있어서 키토산의 효과적인 적용방법을 개발하였고, 양쪽성 고분자 응집제 특성을 가진 화합물을 제조하기 위하여 Maleic acid, Fumaric acid, Itaconic acid와 같은 Alkenedioic acid에 의하여 키토산을 그라프트-공중합하였다. 양쪽성 고분자 응집제는 산성용액중에서 양이온성과 음이온성을 나타냈고 알칼리 용액중에서는 금속이온 제거능이 더욱 향상되어졌다. 금속이온에 의한 폐수에 이들 응집제를 투입하여 1차 처리한 후 여액은 이 응집제로 만들어 진 Bead를 채운 Column에 통과시켜 잔존하는 금속이온을 제거하였다. 그리고 금속이온 제거효율은 여러 종류의 Bead size와 폐수의 유속, 그라프트 공중합의 반응조건등에 따라 시 험하였다. 실험결과, 금속 제거효율은 Column에 충진하는 Bead size가 작을수록, 폐수가 통과하는 유속이 느릴수록 증가하였다. An effective way of application of chitosan to water purification and deminerilization was developed. Chitosan was firstly graft-copolymerized with alkenedioic acids like maleic acid, fumaric acid and itaconic acid, which had an amphoteric flocculant character. An amphoteric flocculant plays like a cationic polymeric flocculant in acidic aqueous solution and also like an anionic polymeric flocculant with remarkably enhanced metal uptaking ability in alkaline aqueous solution. A wastewater contaminated with metals (metal ions) was primarily treated with doses of those agents and then supernatant was forced to pass through columns of beads of those agents to take up metals remained. Metal uptaking efficiencies were examined with variations of sizes of both beads in the column, flow rates of test water and reaction conditions of graft-copolymerizations. The experimental results explain that the of efficiency of metal uptake increases with decrease of beads size and flow rate of test water through columns within this experimental range.

Inhibitory Effect of Chitosan Oligosaccharides on Sialidase Activity In vitro

박제권 한국키틴키토산학회 2010 한국키틴키토산학회지 Vol.15 No.2

Inhibition studies have been exploited in the design of a potent polyvalent inhibitor of the sialidase. A study was conducted to investigate the inhibitory effect of chitosan-oligosaccharides referred to (GlcN)n on Sialidase (SDase) activity in vitro. Major component of (GlcN)n obtained by enzymatic digestion of chitosan was identified to be (GlcN)n, n = 2-5 by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-TOF MS) analysis. Various parameters were monitored for optimization of the inhibitory activity of (GlcN)n and other relative compounds on SDase. The results provided evidence for inhibitory effect;(GlcN)n in suppressing SDase activity in vitro and also provided useful information for the further development of chitosanoligosaccharides (GlcN)n as a potential antiviral agent.

Characterization and Immunostimulating Activity of a Water-soluble Polysaccharide Isolated from Haematococcus lacustris

박제권,김지훈,이철균,Andriy Synytsya,조항수,김성욱,박주웅,박용일 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.6

A water-soluble polysaccharide was isolated and purified from the culture filtrate of the photosynthetic green microalgae Haematococcus lacustris by 75% ethanol precipitation and Sepharose CL-6B column chromatography. The molecular mass of the purified polysaccharide (named HCP) was estimated to be approximately 135 kDa by sizeexclusion HPLC and its monosaccharide composition was galactose, glucose and mannose at a relative molar ratio of 2.0, 1.0, and 4.1, respectively, suggesting that HCP is a galactomannan. Fourier-transform infrared and elemental analysis revealed that the purified HCP contains sulfate esters by 1.08% (in mass) and no detectable level of protein. The HCP significantly stimulated murine macrophage RAW264.7 cells to secrete the pro-inflammatory cytokine,TNF-α, in a dose-dependent manner and also enhanced the expression of COX-2 and iNOS genes at a concentration of lower than 10 μg/mL HCP. These results indicated that the sulfated HCP of H. lacustris has potent early innate immune stimulating activities.

Effects of Chitosan as a Growth Regulator of the Mealworm Tenebrio molitor

박제권 한국키틴키토산학회 2023 한국키틴키토산학회지 Vol.28 No.1

The effects of high molecular weight chitosan (HMWC) and its hydrolysates with different degrees of deacetylation (DD) and molecular weight (MW) on mealworm growth were verified. Differences in body length and weight of mealworms by DD and MW of chitosan added with wheat bran as a basic growth control were compared as a basic control. As a result of evaluating the viability of mealworms by the MW or DD of chitosan in continuous culture for about two months, a survival decrease of less than 10% compared to the control group was evaluated. In addition, as a result of assessing the substrate specificity according to the isolation of mealworm intestinal microorganisms, significant enzymatic activity to degrade pNP-GlcN and pNP-(GlcNAc)2 was verified. It is believed that it is due to the chemical structural properties of chitosan that it possibly contributes to the metabolism of intestinal microbes. The point to be emphasized is that in the industrial aspect, growth inhibition for a certain period of time in the process of storage and continuous cultivation of mealworms can solve the problem of storage that must be stored in a complete growth inhibition state. Therefore, the application of chitosan as a mealworm growth regulator according to the difference between DD and MW can be expected. The results of this study should be evaluated in that it provides important information for understanding the correlation between metabolism and growth of intestinal microorganisms, since it may be critical to control the growth rate, especially in the larval state.

Matrix Sensitivity and Interpretation for Precise Molecular Weight Analysis of Chitosan Hydrolysates

박제권,Song Jio,Lee Eung Take,이지현,Yong Hyun Lee 한국키틴키토산학회 2022 한국키틴키토산학회지 Vol.27 No.2

The biological activity of chitosan differs depending on the molecular weight and degree of deacetylation, so more precise molecular weight determination has become more important. It is difficult to determine the absolute molecular weight size due to the lack of precision, whereas the approximate molecular size is determined using HPLC. Therefore, the hydrolysates using acid or enzyme were subjected to precise molecular weight analysis by using Matrix-Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF). For analysis, two types of matrices were used in this study. The results showed slight differences in sensitivity but were confirmed to be similar to each other. In addition, it was confirmed that any matrix used in this study did not significantly affect the results. In conclusion, the results of this study will provide very important scientific clues in the investigation of the biological activities of chitosan such as antibacterial, anticancer, immune, and antioxidant activity

BT 맨의 출사표

박제권 한국생물공학회 2008 BT NEWS Vol.15 No.2

키틴아제의 분포 및 그 유용성

박제권,이철균 한국키틴키토산학회 2008 한국키틴키토산학회지 Vol.13 No.3

Chitin is a structural linear homopolysaccharide composed of β-(1,4)-N-acetylglucosamine residues, widely spread in whole in the world. It is a major component of cell walls of fungi, exoskeleton of vertebrates, and shells of shrimps and crabs, and so on forth. Eventually, many earlier works demonstrated that marine bacteria such as Vibrios were preliminary responsible for this masive turnover in marine biosphere. In recent, chitinases, catalyze the hydrolysis of chitin, have received increased attention because of their wide range of potential applications in various fields, playing an important role in converting chitin to a biologically and biochemically functional forms. Moreover, chito-oligosaccharides produced by chitinases have been utilized in many fields of applications in agricultural, biology, biomedical, antifugal, and food additives. In this article, we have reviewed the diversity and an industrial application of chitinases.

A Study on the Correlation between Structural Characteristics and Biological Activity of Water-soluble Chitosan

박제권,송지오,김규현,김효은,구본건 한국키틴키토산학회 2023 한국키틴키토산학회지 Vol.28 No.2

The kinetic properties of chitosanase according to chemical and structural modifications of chitosan were evaluated by relative enzyme activity and bioactivity of hydrolysates. Changes in the specificity of the chitosanase for the substrate showed a significant difference under the optimal reaction conditions. The increase of reducing sugar content according to the activity of the chitosanase was significantly observed against carboxymethyl-chitosan (CM-CTSN) compared to glycol chitosan (GL-CTSN) and water-soluble chitosan (WSC) used as a control. Each chitooligosaccharide designated to COS, CM-COS, and GL-COS showed similar results in various antioxidant activity evaluations so that no significant difference could be confirmed. Significant antibacterial activities of three types of water-soluble chitosanderived COS, CM-COS, and GL-COS against Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) were not confirmed. However, both ferric reducing antioxidant power (FRAP) and 2,2’-azino-bis (3-ethylbenzothiazoline6-sulfonic acid) diammonium salt (ABTS) radical scavenging ability confirmed their significant antioxidant activity, but it was evaluated as irrelevant to the difference in molecular weight. Although there is a clear difference in the substrate specificity of the enzyme depending on the chemical structural modification of chitosan, our results suggest that the biological activity of COS was not significantly affected regardless of the presence or absence of a water-soluble functional group. Therefore, based on the results of this study, we suggest the need for follow-up studies to investigate the correlation between the water solubility of chitosan, enzymatic activity, and biological activity.

키토산아제(ChoA)의 대장균체내에서의 대량생산 및 이를 이용한 키토산의 저분자화

박제권,히데유끼마쯔다 한국키틴키토산학회 2000 한국키틴키토산학회지 Vol.5 No.3

A chitosanase gene, designated to choA encoding one of chitosanases of Matsuebacter chitosanotabidus 3001 was cloned in Escherichia coli. In order to construct the chitosanase gene into an high-level expression vector, the gene choA was subcloned into an ITPG inducible vector pFLAQ. The recombinant plasmid DNA pFLAQ: choA was introduced into E. coli DH5a. Chitosanase (34-kDa) was successfully overexpressed in E. coli cell harboring the recombinant pFLAQ: choA. A highly sensitive and selective high-performance liguid chromatography (HPLC) has been developed for the analysis of chitooligosaccharides. The hydrolyzates were derivatized with PMP (1-phenyl-3-nethyl-5-pyrazolone), and its were quantitated by HPLC with monitoring in UV absorbance at 245 nm. Chitosan oligosaccharides, (GlcN)n, n=2~4 and some soluble materials (>5), were produced by using highly expressed chitosanase involved in crude extract which was partially Purified. GlcN2-4 was mainly observed in the reaction mixture, whereas purified chitosanase mainly producing GlcN2. Furthermore, GlcN2-4 was purified in gam-scale using an anion exchange column Dowex50WX8-200 eluted by gradient from 0 to 4.0 M ammonium formate(PH 4.5). In addition, purified chitosan oligosaccharides (GlcN)n, n=2-4 were acetylated with 3H-acetic anhydride for further study.

Purification and Characterization of a Polysialic Acid-specific Sialidase from Pseudomonas fluorescens JK-0412

박제권,Doo Jin Choi,JINCHENGMIN,Ha Na Choi,Joo Woong Park,장성재,추영국,이철균,박용일 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.3

An enzyme with polySia degrading activity was purified from a culture filtrate of Pseudomonas fluorescens JK-0412 to apparent homogeneity using DEAE-Sepharose CL-6B column chomatography and fast performance liquid chomatography separation on a Mono-Q column. The molecular mass of the purified enzyme (tentatively named Endo-PS) was approximately 20 kDa on SDS-PAGE and 120 kDa on native-PAGE gels,suggesting that the active form is a hexamer. Although 12residues of the Endo-PS N-terminal amino acid sequence showed 75% homology to the 21 kDa chitin binding protein (CBP21) of Serratia marcescens 2170, no significant similarity to other known proteins was observed. Apparent Km and Vmax values of Endo-PS toward the artificial substrate 4-methylumbelliferyl-sialic acid (4-MU-Neu5Ac)were 0.08 mM and 16 nmol/mg/min, respectively. The enzyme was maximally active at 37oC and pH 8.0. Interestingly, the enzyme was shown to hydrolyze the natural substrate, α2,8-linked polySia (colominic acid), in an endo-acting manner. However, no activity toward α2,3-or α2,6-sialyllactose was observed. Under optimal conditions,oligoSia ranging from 2 to 30 residues long were liberated by the cleavage of polySia, as identified by HPAEC-PED. Therefore, the purified enzyme Endo-PS was found to be a polySia-specific sialidase. This is the first report to describe the properties of a bacterial polySia-specific sialidase. Therefore, this enzyme may be a useful tool for both industrial oligoSia production and research on the structure and biological functions of polySia in nature.