Earticle

The acetone-butanol fermentation by C. acetobutylicum has gained increasing attention for the following reasons. First, the finite supply of petrochemical resources, combined with increasing concern over global environmental effects and the unstable nature of the price of petroleum has renewed interest in the development of fermentation technology that allows utilzation of biomass wastes for the production of alcohol. Second, it serves as excellent model system for understading the regulation and molecular biology of tightly regulated complex primary metabolism, and for applications of metabolic engineering. In this review various aspects of acetone-butanol fermentation by C. acetobutylicm including strain and fermentation characteristics, enzyme regulation, and solvent formation mechanism, and product recovery and summarized.

The use of Jerusalem artichoke containing B-1, 2-fructose oligomer for the production of D-sorbitol and L-sorbose has been studied. The employment of inulinase(0.398%, v/v) for the hydrolysis of 40% (v/w) Jerusalem artichoke juice resulted in 36.7g/1 of glucose and 85.3g/1 of fructose at 50℃. These sugars were utilized as substrates for D-sorbitol and L-sorbose production. Coimmobilization of inulinase and permeabilized cells of Zymomonas mobilis in the mixture of chitin (5%, w/e) and x-carrageenan(4%, w/v) resulted in the production of 30.2g/1 of D-sorbitol by using inulin as a substrate. The process of L-sorbose production from D-sorbitol by Gluconobacter suboxydans was optimized with respect to the substrate concentration, level of dissolved oxygen and glucosic and concentration. Gluconlc acid produced by Zymomonas mobilis from glucose was found to inhibit Gluconobacter suboxtans in conversion of D-sorbitol to L-sorbose. In view of removing such inhibitory effect by gluconic acid, mutants were selected by the NTG (N-methyl-N'-N'-nitro-N-nitrosoguanidlne) treated method. Mutants selected by NTG mutagenesis showed no inhibitory effects of gluconic acrid against L-sorbone production when its concentration increased up to 100g/1. A mutant produced 40.1g/l of L-sorbose in the medium containing 100g/l D-sorbitol and 100g/l-gluconic acid. This result is consider able when compared with L-sorbose concentration (21.7g/1) obtained from the fermentation with wild type strain of Gluconobacter suboxnians.

1.96x10-5(IU/cell/hr) of specific scu-PA production rate was obtained from HEK cells in maintaining ca. 8x105(cells/ml) of maximum roll density at 10(ml/hr) of perfusion rate with recycling 20% serum free conditioned media. It can be compared to 4x106(cells/ml) of maximum cell density and 4.56x10-4(IU/cell/hr) of specific production rate in cultivating cells with 1% serum containing medium. Thc conversion ratio of scu-PA to tc-UK increased up to 55% as the recycling ratio increased; however, recycling the used medium seemed to have least negative effect on cell growth. It also showed that the recycling process had definitive advantage of using serum free medium in perfusion cultivation of HEK cell line.

The serum free medium was developed and used for the suspension culture of mammalian cells. Although there were the problems of the longer lag time and the smaller maximum cell concentration achievable, the higher specific productivity as well as other advantages of the serum free medium can make it a more realistic alternative. The existence of a staggering period in glucose concentration vs. time profile in the batch culture can be a practical indicating signal for performing fed batch culture. The concentration dependence of the effects of the additives in the serum free medium as well as its economic feasibility was also tested.

본 연구는 포름알데히드를 분해하는 균주를 하천의 진흙에서 6종 분리하고 그 중에서 포름알데히드의 분해능이 가장 우수한 균주인 H-5을 분리동정하여 Pseudomonas putida H-5라고 명명 하였다. Pseudomonas putida H-5의 최적 생장조건은 온도 30℃, pH 7.0이었고, 포름알데히드는 0.02~0.04% 의 농도에서 가장 분해가 잘 되었고, 기질로는 glucose가 가장 우수하였다. Pseudomonas putida H-5에 의하여 포름알데히드는 메탄올과 개미산으로 분해되며 이는 균주의 생육에 아무런 영향을 미치지 않았다

This study was designed to reveal the characteristics of the strains degrading formaldehyde isolated from mud of waste water. A strain H-5 showed the highest ability of formaldehyde biodegradation among isolated strains. According to identification, the strain H-5 was ascribed to be Peudomonas putida H-5. The optimal conditions of Peudomonas putida H-5 were 30℃ and pH 7.0. The highest level of formaldehyde degradation was demonstrated at the concentration of 0.02~0.04% in a glucose containing medium. Formaldehyde biodegradation by Peudomonas putida H-5 indicated that this reaction was converted to the methanol and formic acid. However, methanol and formic acid did not show any effect on the growth of viable cells.

Continuous degradation of formaldehyde by using a rotating disc contactor was investigated in this study. Peudomonas putida H-5K was selected as a mutant using N-methyl N'-nitro N-nitrosoguandine (250ug/ml), which showed 1.5 times higher ability of formaldehyde degradation than that of the parent strain. Enzyme activity for formaldehyde degradation released form Peudomonas putida H-5K showed the highest level of 6.2mo1/min/mg protein in the 2% glucose mineral medium containing 0.02% formaldehyde. Degradation of formaldehyde from the first stage in rotating disc contactor was 95% and 5% from the 4th stage when the reactor was fed with 0.02% or 0.04% formaldehyde solution at a rate of 20 ml per hour. Continuous degradation of formaldehyde using rotating disc contactor was above 95%o in the medium containing 0.04% formalchyde, at the medium feed ratc of 20ml per hour.

천연식품인 호도, 복숭아씨, 살구씨의 지방산 함량 과 홀수 지방산의 함량을 규명하기 위하여 HPLC를 사용하여 분리 정량한 결과는 다음과 같다. 1. 각 시료의 조지방 함량은 호도 61.78%. 살구 씨 52.34%. 복숭아씨 48.21 %이고, 중성 지질량은 호도 62.32%, 복숭아씨 91.50%. 살구씨 88.0%이 고, 당지질은 호도 34.14%, 복숭아씨 3.25%. 살구 씨 4.78%이었고, 인지질은 호도 3.54%. 복숭아씨 5.25%. 상구씨 7.27%였다. 2. 중성지질의 지방산에서 호도의 홀수 지방산이 3 37.07%. 짝수 지방산이 36.72%. 복숭아씨의 홀수 지방산이 5.4%, 짝수 지방산이 94.60%. 살구씨의 홀수 지방산이 6.85%. 8 짝수 지방산이 93.92%였교, 당지질에서 호도의 홀수 지방산은 53.7%. 짝수 지 방산은 46.21 %. 복숭아씨의 홀수 지방산은 6.97% . 9 짝수 지방산은 93.03%, 살구씨의 홀수 지방산은 10.5%, 짝수 지방산은 89.42 %였고, 인지a질에서의 경우는 호도의 홀수 지방산이 3.57%, 짝수 지방산 이 96.43%, 복숭아써의 흘수 지방산이 6.51 %, 짝 수 지방산이 93.49%, 살구씨의 홀수 지방산이 15.0 % %, 짝수 지방산이 84.2%로 각각 함유되어 었다. 3. 총 지방산중 홀수 지방산은 호도 14.47%, 복 숭아씨 1.17%, 상구씨 4.03%이고, 짝수 지방산은 호도 85.53 %, 복숭아씨 98.83%, 삼구씨 95.97% 로 각각 함유되어 있음을 알 수 있다. 수 있다.

Ginkgo biloba의 세포배양을 통하여 세포성장과 flavonol glycosides의 생성에 영향을 미치는 여러 조건들을 연구하였다. 다양한 지역으로부터 유도된 세포주들의 세포성장과 flavonol glycosides의 생합성 능력은 서로 차이가 있었다. 이들의 캘러스 및 현탁 세포는 배지조건과 배양조건에 따라 성장 및 f1avonol glycosides 생합성에 많은 영향을 받았었다. 특히 배양조건 중 빛의 영향은 현저하여 명조건에서의 f1avonol glycosides의 생성은 암조건보다 10배 이상 증가함을 알 수 있었다

Cell lines of Ginkgo biloba were derived from different plant parts and from ten varieties spanning various geographic locations. They had various properties of growth and product formation. More than three flavonol glycosides were present in low concentration in callus and suspension cultures. Cell growth and biosynthesis of flavonol glycosides were found to be affected by medium composition. Culture conditions which influenced cell growth and product formation were also examined. Light stimulated the flavonol glycosides biosynthesis and ten times higher flavonol glycosides content was obtained as compared with the result without light.

Transformed rice plantlet were recovered from protoplasts by electroporation with the plasmld pB 1121, which contain the plant expressible NPT-II and GUS genes. Embryonic cell suspension culture was established with embryonic callus induced from mature seeds of rice (Oryza sativa L. cv. Dong-jin) on the MS medium supplemented with 2.0 mg/l 2,4-D, 0.5 mg/l kinetin, 3% sucrose. Protoplasts isolated from embryonic cell suspensions were electroplated and then poterltialty-transformed tissues were selected by growth on the medium containing 200 mg/l kanamycin sulfate. When subjected to GUS assay, they stained blue, indicating the expression of the inserted GUS genes. Plantlets were regenerated from electroplated protoplasts on the hormone free MS medium. Transferred foreign genes in the plants were confirmed by southern hybridization. These results support use of electroporation for transformation of these important cereal plants.

Cacao bean외피로부터 분리된 물질은 anisaldehyde-H2SO4 및 FeCi3에 각각 갈색 및 청색반응을 하였고 TLC상에서 monomer 및 dimer의 fIavan-3-ol 물질로 확인되었다. 물질의 구조를 NMR로 검정한 결과 compound I 과 II 는 각각 (-)-epicatechin과 epicatechin-(4a→8)-epicatechin의 결합 화합물인 procyanidin B-2이었다. 분리된 두 화합물은 GTase에 대해 높은 저해활성이 있었고 특히 procyanidin B-2는 1.0mM에서 완전히 저해시켰다. 이것은 f1avan-3-ol 구조내에 OH가의 증가에 따라 GTase 저해활성도 높아지는 것으로 추정되었다.

For an anti-plaque agent, two flavan-3-ols isolated from Theobroma cacao bean husk showed positive reactions with H2SO4-anisaldehyde solution, FeCl3, and were identified as monomeric, dimeric flavan-3-ots in TLC. They were (-)-epicatechin and procyanidin B-2(epicatechin-(4B→8)-epicatechin). The structures were established by spectroscopic and chemical methods. (-)-Epicatechin had moderate inhibitory activity on GTase at concentration of 1.0mM while procyanidin B-2 showed complete inhibition activity at the same concentration. The hydroxyl group of flavan-3-ol was supposed to be the essential element for inhibition on GTase.

The inhibitory effect of cacao bean husk (CBH) extract on glucosyltransferase(GTasc) from Streptococcus mutans B13 was investigated. Water solube extract from CBH showeda sarong inhibitory effect (88-89%) on GTase from Streptococcus mutans Bl3. GTase inhibitors from sequential extraction by hot water or water-methanol had the strongest inhibition. Sources, fermentation, and types of solvents and fumigation processes did not influence the effect. These active compounds proved to be polyphones through acid hydrolytic analysis of the precipitates by ammonium sulfate or ethanol and proteinase K. It was also confirmed by additional column chromatography of Sephadex G-50, Sephadex LH-20 and DEAE-Sephdex A-50.

연속추출시 그 상의 분리가 용이한 spray column 에서 역미셀을 이용한 추출에 영향을 미치는 pH, 접촉횟수, 유속, 수용상과 유기상의 비 등 추출에 영향을 미치는 여러 인자들을 조사해 보았다. 그 결과 lipase는 등전점보다 낮은 3.6-4.5 사이에서 추출이 잘되었으며 역추출시에는 그와 반대로 등전점보다 높은 pH인 8.0-9.0에서 잘 추출되었다. 수용상과 유기상 사이의 접촉횟수가 증가함에 따라 추출량이 증가되었으며 추출시 계면활성제의 손실 때문에 유기상의 계속적인 공급이 필요하다. 유속의 효과는 접촉면적과 유기상 사이의 물의 함량의 반대효과로 0 0.068ml/sec과 0.101ml/sec사이에서 최적의 값을 갖는다. 수용상과 유기상간의 비에 따른 추출량은 예측했던데로 수용상의 양이 많을수록 그 추출량이 급격히 증가하는 경 향을 보였다. 각각에서 활성도는 추출전에 비해 70%의 회수율을 보였다.

Lipase was separated using reverse mlcelles in a spray column. The 50 mM AOT-Isooctane solution was used as reverse micellar solution for the extraction of lipase (crude containing 25% Protein). Ionic strength was controlled by KCl(0.1M KCl for extraction, 0.5M KCl for back exlractlon). Acetate buffer and phosphate buffer were used for control of pH. The efficiencies of extraction and stripping were 30% and 50%. An increase of circulation did not change the efficiency of extraction in forward extraction. The optimum flow rate was around 0.10ml/sec.

Thc effect of light and phylohormonc on the belalaln synthesis was tested using the suspension culture of a rod(bclalaln produulng) cell line from Phytolacca esculenta V. Houtte. Betalain synthesis of rod-cell 1ine was strongly dependent on the irradiation of blue light, but induced by hormone, IAA and/or kinetin, in dark conditions. In a light condition, however, 2 mg/l of IAA increased the betalain content about 30% (per gram fresh weight), whereas more than 0.5mg/l of kinetin remarkably decreased. The hairy root derived from the same plant was also observed for the blue light-dependent pigmentation in the root-tips. When the hairy root grown in dark was transferred to the light condition, the accumulation of betalain was initiated after 12hours. Such pigmentation was completely inhabited by addition of a protein synthesis inhibitor.