This study was conducted to investigate the protease expression patterns of the novel chitinase-producing bacterium Pedobacter sp. PR-M6. Protease were detected on SDS-PAGE gel as condition of 4℃, 25℃ and 37℃ to activate of enzymes obtained from incubation of LB, NB and 1% skim milk medium at 4℃, 20℃ and 30℃ after 21 days of incubation, respectively. Pedobacter sp. PR-M6 displayed proteolytic activity on SDS-PAGE gels containing 0.1% (w/v) gelatin, and protease isozymes of PR-M6 were expressed as two major bands (P7 and P8) and seven minor bands (P1, P2, P3, P4, P5, P6, and P9). Protease isozymes of PR-M6 were inhibited at 4℃ and 25℃. The two protease isozymes P5 and P6 were newly expressed in the LB culture medium at 20℃. To investigate the properties of a heat-stable antifungal factor (HSAF), PR-M6 stain was cultured to obtain the products of biosynthesis for incubation in LB medium. HSAF exhibited active biosynthesis at 20℃ for incubation in LB medium. Crude HASF obtained from LB20 medium showed hyphal growth inhibition of Rhizoctonia solani. Inhibition rate of R. solani growth was as high as 67% at 24 h and 47.8% at 48 h after incubation with 1,000 ppm of crude HSAF. Trypan blue stained the inside of the edge for destructed R. solani cell walls after crude HSAF treatment. These results indicated that HSAF and protease from Pedobacter sp. PR-M6 could be used as biocontrol agents against phytopathogens in agriculture.

This review aims to present the possibility of using it as a pet food additive and the main raw material in consideration of published journals with a thesis that utilizes research on functional food materials derived from marine resources. Functional food materials derived from the marine resources are widely used as foods in Korea, and many studies have been conducted. In addition, food materials derived from the marine are used as pet food, but research on pet food additives and the main ingredients is insufficient. The results of this study showed that marine food materials are used in various pet food products and have sufficient function and nutritional value as pet food. Therefore, the use of pet food additives and main raw materials derived from marine resources are expected to increase the competitiveness of the domestic feed industry and satisfy the consumer's needs. In addition, increasing the use of pet food made by seaweed is one of the good ways to be carbon neutrality. Accordingly, it is suggested that expand the empirical research using companion animals on the raw materials for functional pet foods derived from marine resources along with the development of mass production technology and supply system for marine resources.

This study was carried out to very precisely understand the effect of solvent selection on the molecular properties in the investigation of the biological activity according to the molecular size of chitosan. Chitosan hydrolysates derived from the hydrolysis of high molecular weight chitosan (HMWC) were prepared in enzymatic hydrolysis under solvent selective conditions. Chitosan hydrolysates were characterized by HPLC and Matrix-Assisted Laser Desorption/ Ionization-Time of Flight (MALDI-TOF) mass spectrometry analyses, respectively. HPLC analysis did not show a significant difference in the size of hydrolysates according to the type of chitosan. On the other hand, it was confirmed that each molecular size was significantly different from the results presented by HPLC with MALDI-TOF mass spectrometry analysis. In addition, the effect on the antibacterial activity of the hydrolysates of chitosan, designated to “active molecular chitosan (AMC)”, by the solvent selected for the enzymatic reaction also showed a significant difference. Therefore, it is intended to suggest that the selection of solvents for the enzymatic reaction for chitosan hydrolysis and their antibacterial activity is very important.

본 연구는 환경재료로써 수질 관리 및 수처리를 위한 키토산 기반의 처리 공정과 개질된 물질에 대해 나타냈다. 키토산은 농업 분야, 생명공학 분야 및 환경공학 분야 등 소재를 필요로 하는 분야에 적용 가능한 재료로 키토산의 물리-화학적 장점(예: 생분해성, 항균성, 무독성, 바이오 적합성 등)은 환경재료로써 경제적, 효율적으로 처리 결과를 향상하는 데 중요한 역할이 가능하다. 흡착, 흡수, 응집 및 응결 등의 기반 작용을 통해서 수질 내에 존재하는 여러 종류의 오염물질을 효율적으로 저감 및 제거하고 키토산 기반의 나노 복합체 제조 등을 통해 직접 적용이 어려운 분야로의 응용이 가능하도록 하였다. 또한, 수질 환경에서 장기적으로 발생 가능한 생물학적 오염을 방지할 수 있는 기초 능력을 보여주고 있기에, 이를 활용한 실용적인 응용은 향후 환경재료 및 환경처리 공정의 확장성에 있어서 크게 기인할 수 있다고 판단된다.
다만, 최근 발생하고 있는 지구 온난화에 의한 해수 수온의 변화가 우리나라 인근해에서 포획되는 갑각류의 어획량을 감소시킴에 따라 키토산의 원료 수급에 차질이 있을 수 있으며, 이러한 원료 문제를 해결하지 못한다면 키토산 산업에 저해가 될 수 있는 요인으로 작용할 것이다. 또한, 현재의 키토산을 추출하는 데에 있어서 방법론적 한계(예: 강산과 강염기를 사용한 화학반응에 의한 추출 등)를 가지고 있는데, 이러한 한계를 극복할 수 있는 기술 개발과 대체 원료 물질을 생산할 수 있다면 키토산을 활용할 수 있는 산업은 크게 발전할 수 있다고 생각한다. 본 연구에서 서술한 천연고분자 물질로써 개발할 수 있는 이온성 물질 흡착제 및 수처리용 응집제 뿐만 아니라 친환경 원료로써 다양하게 적용될 가능성을 가지고 있다고 볼 수 있으며, 이러한 산업 발전을 위한 꾸준한 연구와 기술개발이 필수적으로 수반되어야 한다고 판단된다.

Chitosan is an economic material applicable to fields of agriculture, biotechnology, and environmental engineering, especially, in the field of water quality managements. The main mechanisms to remove contaminants in water are adsorption, chelation, precipitation, ion exchange, and various reactive functional groups present on the chitosan surface (e.g., amino or hydroxyl group). This review is to summarize the results of many studies regarding the removing contaminants in water phase (e.g., oily substances, toxic materials, suspended solids, humus, dye materials, heavy metals, non-metals, drugs, and emerging contaminants such as pharmaceuticals and personal care products etc.) by chitosan and derivatives. This review explains the examples of the use of chitosan materials to control these contaminants and introduces the current and potential applications of chitosan in the future of environmental fields.

본 연구에서는 후코이단의 의·약학적 활용 범위를 넓히기 위해 글리콜키토산을 이용하여 나노복합체를 제조하였고, 염증 저해 효과를 살펴보았다. 후코이단은 글리콜키토산과 이온결합을 통해 나노 크기의 복합체를 성공적으로 형성하였다. 글리콜키토산-후코이단 나노복합체의 평균 입자 크기는 406.0±20.3 nm이며 전자 주사현미경을 통해 구형의 형태를 확인하였다. 글리콜키토산-후코이단 나노복합체는 대식세포 RAW 264.7에서 LPS로 유도된 NO의 생성을 저해하고 iNOS 및 COX-2 단백질 발현을 억제하는 효과가 있었다. 따라서, 본 연구에서 제시한 글리콜키토산-후코이단 나노복합체는 후코이단의 항염증 효과를 가지고 나노복합체를 형태를 형성함으로써 기능성 식품, 화장품, 제약 산업에 다양하게 활용될 수 있을 것으로 기대된다.

To improve the application of fucoidan in the biomedical field, we prepared glycol chitosan-fucoidan nanocomplexs (GC-Fu NC) through electrostatic interaction. The anti-inflammatory activities of GC-Fu NC were investigated in RAW 264.7 cells treated with lipopolysaccharide (LPS). Effects of GC-Fu NC on the production of pro-inflammatory factors (iNOS and COX-2) in LPS-stimulated RAW 264.7 cells were evaluated. GC-Fu NC were spherical with an average diameter of 406.0 ± 20.3 nm. In the cytotoxicity studies, GC-Fu NC did not show toxicity on RAW 264.7 at high concentration of 200 ppm. When LPS-stimulated RAW 264.7 cells were treated with GC-Fu NC, production of nitric oxide was inhibited in a concentration-dependent manner. In addition, induction of iNOS and COX-2 in the stimulated RAW264.7 cells was inhibited by treatment of GC-Fu NC. In conclusion, GC-Fu NC are expected to exhibit the effect of inhibiting the progression of inflammation. Furthermore, we expect that GC-Fu NC have great potential for application in food, cosmetics, and pharmaceutical industries.

The purpose of this study was to investigate the cytoprotective effects of a neutrase enzymatic hydrolysate derived from Buccinum striatissumum (BSMN) against hydrogen peroxide (H2O2)-induced oxidative damage in hepatocytes. BSMN effectively scavenged the 2,2-azino-bis (3-ethylbenzthiazoline)-6-sulfonic acid radical (ABTS) and increased the oxygen radical absorbance capacity (ORAC) value by incresing the reducing power. Also, BSMN markedly increased the cell viabiltiy by inhibiting the intracellualr reactive oxygen species (ROS) production in H2O2-stimulated hepatocytes. In addition, BSMN decreased the sub-G1 DNA contents and apoptotic body formation increased by regulating the apoptosis related proteins (Bcl-2, Bax and p53). Moreover, BSMN activated the Nrf2/HO-1 signaling pathway by suppressing the activation of NF-κB and ERK/p38 signaling pathway in H2O2-stimulated hepatocytes. These results suggest BSMN protects hepatocytes against oxidative stress caused by H2O2 stimulation