• 제목/요약/키워드: Acid Hydrolysis

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표고버섯의 열수추출 다당류 및 비타민 A와 E 첨가가 $P_388$의 세포독성에 미치는 영향 (Cytotoxic Effects of Hot Water Soluble Polysaccharides from Mushroom, Lentinus edodes and Vitamin A & E Supplementation against $P_388$ Cells)

  • 최미연
    • Journal of Nutrition and Health
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    • 제28권11호
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    • pp.1091-1099
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    • 1995
  • The cyutotoxic effects of hot water soluble polysaccharides extract(PS) from the mushroom, Lentinus edodes, and in combinations with vitamin A or vitamin E on life span of ICR mice bearing P388 cancer cells and in vitro against P388 cancer cells were examined. The chemical components of PS and fractions were analyzed and survival time and cell number of P388 treated with extract fractions with and without vatamin A or E supplementation were also measured. The results obtained were summarized as follows; The extract of fraction B was shown to have the highest antitumor activity against P388 implanted in ICR mice. The antitumor fraction B was consisted of 82.0% of polysaccharide and 4.2% of protein. All three fractions seemed to have in vivo antitumor activity against P388, and fraction B showed the highest activity, In vitro P388 cell growht was inhibited 76%, 89%, 54% by the addition of fraction A, B and C respectively. Vitamin A or E did not appear to have any accelerating effects on either in vivo or in vitro cell cytotoxicity when each of them was combined with the PS and fractions. All three fractions contained more than 68% of polysaccharides. The fraction B showed the highest value of 88% in polysaccharides. Monsaccharides of the fraction B were identified as galactose(59.1%), glucose(29.2%), fructose(2.8%) and uronic acid(4.2%). Hydrolysis of protein from the fraction B was didentifed to have 17 kinds of defined and 5 undifined amino acids. The inhibitory effects of the hot water extracts from mushroom against cancer cell growth of P388 were stronger than the control group. And the survival time of ICR mice was shown to be 161% between the control group and the experimental groups.

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이산화티탄 나노입자로부터 고굴절 하드코팅 도막의 제조 (Preparation of Hard Coating Films with High Refractive Index from Titania Nanoparticles)

  • 김남우;안치용;송기창
    • Korean Chemical Engineering Research
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    • 제53권6호
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    • pp.762-769
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    • 2015
  • 직경 2~3 nm 크기를 갖는 이산화티탄 나노입자가 산성 용액에서 titanium tetraisopropoxide(TTIP)의 가수분해 반응을 조절함에 의해 합성되었다. 생성된 이산화티탄 나노입자를 졸-겔법에 의해 3-glycidoxypropyl trimethoxysilane(GPTMS)과 반응시킴에 의해 유-무기 혼성 코팅 용액이 제조되었다. 그 후 코팅 용액을 기재인 polycarbonate(PC) 시트 위에 스핀 코팅시키고, $120^{\circ}C$에서 열경화 시켜 고굴절률 하드코팅 도막이 제조되었다. 코팅 도막은 가시광선 영역에서 90%의 높은 광학적 투과율을 보였으며 2H의 연필경도를 나타내었다. 또한 코팅 용액 내의 이산화티탄 나노입자의 함량이 4%에서 25%로 증가됨에 따라 코팅 필름의 굴절률은 633 nm 파장에서 1.502로부터 1.584로 향상되었다.

미세결정셀룰로오스의 제조를 위한 억새 바이오매스의 처리 및 특성연구 (Study of Preparation and Characterization of Microcrystalline cellulose from Miscanthus sinensis)

  • 성용주;이영주;이준우;김세빈;박관수;신수정
    • 펄프종이기술
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    • 제42권4호
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    • pp.56-63
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    • 2010
  • Microcrystalline cellulose (MCC) was prepared from Miscanthus in this study. Two pulping methods, soda pulping and alkaline sulfite pulping were applied as a pretreatment process. After pulping, two different bleaching processes such as $ClO_2$ treatment followed by $H_2O_2$ treatment and $O_3$ treatment followed by $H_2O_2$ treatment were carried out. Two concentration of $H_2SO_4$, 47% and 57% were applied to the purified Miscanthus cellulose as a acid hydrolysis process to make MCC. The crystallinity index and morphological properties of the produced MCC were evaluated with X-ray diffractometer and scanning electron microscopy. The MCC originated from the soda pulping sample showed the higher crystallinity index than that originated from the alkaline sulfite pulping sample. The two stages of treatmen twith $O_3$ and $H_2O_2$ resulted in the higher purified cellulose products.

Methanopterin과 관련된 6-[1-(4-Ribitylanilino)ethyl]-1,3,7-trimethyllumazine의 합성 (The Synthesis of 6-[1-(4-Ribitylanilino)ethyl]-1,3-dimethyllumazine Related to Methanopterin)

  • 장용진;김연희;강용한
    • 대한화학회지
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    • 제43권6호
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    • pp.670-675
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    • 1999
  • Methanopterin의 pteridine부분과 관련있는 구조를 가지는 6-[1-(4-ribityl-anilino)ethyl]-1,3,7-trimethyllumazine (2)를 합성하였다. 4-Ribitylaniline 유도체는 D-ribose와 N-benzoyl-4-bromoaniIine (7)을출발 물질로 하여 여러 단계를 거쳐 합성되었다. 6-Acetyl-1,3,7-trimethyllumazine (4)는 Timmis 반응을 이용하여 4-amino-1,3-dimethyl-5-nitrosouracil (3)과 2,4-pentanedione을 반응시켜 얻을 수 있었다. 화합물 4는 $NaBH_4$에 의한 환원반응과 뒤이은 $SOCl_2$에 의한 염소화반응으로 6-(1-chloroethyl)-1,3,7-trimethyllumazine (6)으로 변환되었다. 화합물 6과 4-(2,3:4,5-di-O-isopropylidene-D-ribityl)aniline (13)의 친핵성 치환반응으로 6-[1-{4-(2,3:4,5-di-O-isopropylidene-D-ribityl)anilino}ethyl]-1,3,7-trimethyllumazine (14)가 합성되었다 목표 화합물 2는 산 촉매하에서 화합물 14를 가수분해하여 얻어졌다.

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홍조류, 갈조류, 녹조류를 이용한 바이오에탄올 생산 및 폐 해조류 슬러리의 중금속 생물흡착 (Ethanol Production from Red, Brown and Green Seaweeds and Biosorption of Heavy Metals by Waste Seaweed Slurry from Ethanol Production)

  • 선우인영;라채훈;권성진;허지희;김예진;김지우;신지호;안은주;조유경;김성구
    • KSBB Journal
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    • 제29권6호
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    • pp.414-420
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    • 2014
  • The seaweeds with high carbohydrate ratio Gelidium amansii, Saccharina japonica and Enteromorpha intestinalis were used as red, brown, and green seaweeds, respectively. Thermal acid hydrolysis, enzymatic saccharification and fermentation were carried out using those seaweeds to produce ethanol. The ethanol concentrations from red, brown and green seaweed were 14.8 g/L, 11.6 g/L and 9.9 g/L, respectively. After the production of ethanol, the seaweeds were reused to absorb heavy metal. The maximum biosorption ratio was Cu(II) (89.6%), Cr(III) (82.9%), Ni(II) (66.1%). Cu(II) had the highest affinity with 3 waste seaweeds. Red seaweed was verified the most effective substrates to both process.

Affinity Labeling of E. coli GTP Cyclohydrolase I by a Dialdehyde Derivative of Guanosine Triphosphate

  • Ahn, Chi-Young;Park, Sang-Ick;Kim, Ju-Myeong;Yim, Jeong-Bin
    • BMB Reports
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    • 제28권1호
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    • pp.72-78
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    • 1995
  • Time-dependent inactivation of E. coli GTP cyclohydrolase I with a 2',3'-dialdehyde derivative of GTP (oGTP) was directed to the active site of the enzyme, and was dependent on the concentration of oGTP. The kinetics of inactivation were biphasic with a rapid reaction occurring immediately upon exposure of the enzyme to oGTP followed by a slow rate of inactivation. The $K_i$ value of oGTP for the enzyme was 0.25 mM. Inactivation was prevented by preincubation of the enzyme with GTP, the substrate of the enzyme. At 100% inactivation, 2.3 mol of [8.5'-$^3H$]oGTP were bound per each enzyme subunit, which consists of two identical polypeptides. The active site residue which reacted with the affinity label was lysine. oGTP interacted selectively with the ${\varepsilon}$-amino group of lysine in the GTP-binding site to form a morpholine-like structure which was stable without sodium borohydride treatment. However, triphosphate group was eliminated during the hydrolysis step. To identify the active site of the enzyme, [8.5'-$^3H$]oGTP-labeled enzyme was cleaved by endoproteinase Lys-C, and the $^3H$-labeled peptide was purified by HPLC. The amino acid sequence of the active site peptide was Pro-Ser-Leu-Ser-Lys, which corresponds to the aminoterminal sequence of the enzyme.

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Aspartic proteases of Plasmodium vivax are highly conserved in wild isolates

  • Na, Byoung-Kuk;Lee, Eung-Goo;Lee, Hyeong-Woo;Cho, Shin-Hyeong;Bae, Young-An;Kong, Yoon;Lee, Jong-Koo;Kim, Tong-Soo
    • Parasites, Hosts and Diseases
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    • 제42권2호
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    • pp.61-66
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    • 2004
  • The plasmepsins are the aspartic proteases of malaria parasites. Treatment of aspartic protease inhibitor inhibits hemoglobin hydrolysis and blocks the parasite development in vitro suggesting that these proteases might be exploited their potentials as antimalarial drug targets. In this study, we determined the genetic variations of the aspartic proteases of Plasmodium vivax (PvPMs) of wild isolates. Two plasmepsins (PvPM4 and PvPM5) were cloned and sequenced from 20 P. vivax Korean isolates and two imported isolates. The sequences of the enzymes were highly conserved except a small number of amino acid substitutions did not modify key residues for the function or the structure of the enzymes. The high sequence conservations between the plasmepsins from the isolates support the notion that the enzymes could be reliable targets for new antimalarial chemotherapeutics.

Comparison of Antioxidant Activities of Hydrolysates of Domestic and Imported Skim Milk Powders Treated with Papain

  • Ha, Go Eun;Chang, Oun Ki;Han, Gi Sung;Ham, Jun Sang;Park, Beom-Young;Jeong, Seok-Geun
    • 한국축산식품학회지
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    • 제35권3호
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    • pp.360-369
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    • 2015
  • Milk proteins have many potential sequences within their primary structure, each with a specific biological activity. In this study, we compared and investigated the bioactivities of hydrolysates of the domestic (A, B) and imported (C, D) skim milk powders generated using papain digestion. MALDI-TOF analysis revealed that all milk powder proteins were intact, indicating no autolysis. Electrophoretic analysis of hydrolysates showed papain treatment caused degradation of milk proteins into peptides of various size. The antioxidant activity of the hydrolysates, determined using 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total phenolic contents (TPC) assays, increased with incubation times. In all skim milk powders, the antioxidant activities of hydrolysates were highest following 24 h papain treatment (TPC: A, 196.48 μM GE/L; B, 194.52 μM GE/L; C, 194.76 μM GE/L; D, 163.75 μM GE/L; ABTS: A, 75%; B, 72%; C, 72%; D, 57%). The number of peptide derived from skim milk powders, as determined by LC-MS/MS, was 308 for A, 283 for B, 208 for C, and 135 for D. Hydrolysate A had the highest antioxidant activity and the most potential antioxidant peptides amongst the four skim milk powder hydrolysates. A total of 4 β-lactoglobulin, 4 αs1-casein, and 56 β-casein peptide fragments were identified as potential antioxidant peptides in hydrolysate A by LC-MS/MS. These results suggest that domestic skim milk could have applications in various industries, i.e., in the development of functional foods.

酸素의 存在下와 無酸素下에서의 水溶液 및 固體 Glycylglycylglycine의 放射線分解 (Radiolysis of Oxygenated and Deoxygenated Glycylglycylglycine in Aqueous Solution and in the Solid State)

  • Kang, Man-Sik
    • 한국동물학회지
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    • 제13권3호
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    • pp.75-84
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    • 1970
  • 蛋白質의 放射線分解의 기작을 밝히는 연구의 일환으로, 특히 peptide 結合의 분해의 기작을 구명하기 위하여 Glycylglycylglycine의 水溶液과 固體를 酸素의 존재하에서와 無酸素하에서 r 線을 조사하여 分解生成物을 여지크로마토그라프로 분리하였고, carbonyl 化合物과 amide를 각각 分光光度法과 微凉摘定法으로 정량하였으나 放射線障害를 평가하기 위하여 赤外線 spectrum과 紫外線 spectrum을 얻어 검토하였다. 水溶液과 固體에 있어서의 peptide 結合의 분해기작은 근본적인 차이가 있는 것으로 여겨지며, 전자에서는 월등하게 분해가 많이 일어난데 반해서 후자에서는 무시할 정도에 지나지 않았다. 한편, 水溶液의 경우 酸素의 유무에 따라 현저한 영향은 보이지 않았으나 無酸素하에서는 遊離基의 再結合이 일어나는 점이 특기할만 하였다. 水溶液에 있어서의 peptide 結合의 분해기구는 Garrison 一派가 주장한 기작에 의해서 일어나는 것이 분명하여 脫水素反應에 뒤이어 加水分解反應에 의해서 amide 와 carbonyl 이 생성되는 것으로 보이며, 固體의 경우도 $\\alpha$-炭素의 부위가 방사선의 공격을 가장 많이 받는 것으로 추정되나 그 정도는 미미한 것에 지나지 않는 것으로 생각되었다.

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수종의 암세포주에 대한 인삼 사포닌 및 그 분해산물의 구조와 세포독성 관계 (CYTOTOXICITIES OF GINSENG SAPONINS AND THEIR DEGRADATION PRODUCTS AGAINST SOME CANCER CELL LINES AND STRUCTURE-ACTIVITY RELATIONSHIP)

  • 백남인;김신일;이유희;김동선;박종대;이천배
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1993년도 학술대회지
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    • pp.132-137
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    • 1993
  • 한국산 고려 홍삼을 산 또는 알칼리로 가수분해하여, 여러가지 사포게닌과 프로사포게닌을 제조하였으며, 분광학적 데이터와 물리 데이터 등으로부터 이들의 화학 구조를 결정하였다. 이들 중 몇종의 분해산물은 A549, SK - OV. - 3, P388, L1210, SK - Mel - 2 및 K562 등의 암세포에 대하여 세포 독성을 나타내었다. Diol계와 triol계 모두 20번 탄소의 절대구조만이 다른 입체 이성체간의 세포독성의 차이는 인정되지 않았으며, diol 계의 물질들이 triol계 물질보다는 더 높은 활성을 나타내었다. 일반적으로 결합된 탄소의 수가 적을수록 세포독성은 강하여지는 경향??? 보였다.

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