While a range of natural organic matter (NOM) types can generate high levels of disinfection by-products (DBPs) after chlorination, there is little understanding of which specific compounds act as precursors. Use of eight model compounds allows linking of explicit properties to treatability and DBP formation potential (DBPFP). The removal of model compounds by various treatment processes and their haloacetic acid formation potential (HAAFP) before and after treatment were recorded. The model compounds comprised a range of hydrophobic (HPO) and hydrophilic (HPI) neutral and anionic compounds. On the treatment processes, an ozone oxidation process was moderate for control of model compounds, while the HPO-neutral compound was most treatable with activated carbon process. Biodegradation was successful in removing amino acids, while coagulation and ion exchange process had little effect on neutral molecules. Although compared with the HPO compounds the HPI compounds had low HAAFP the ozone oxidation and biodegradation were capable of increasing their HAAFP. In situations where neutral or HPI molecules have high DBPFP additional treatments may be required to remove recalcitrant NOM and control DBPs.

자외선은 생체 내 활성산소 생성 증가와 내인성 항산화 효소 및 항산화제 감소를 통하여 광노화 과정을 촉진하는 대표적인 외부 환경인자로 알려져 있다. 그러므로, 본 연구에서는 12종의 다양한 해양소재 추출물(김, 다시마, 모려, 모자반, 미역, 석결명, 청각, 해룡, 해마, 해삼, 파래, 톳)을 이용하여 기본적인 자유라디칼 소거능 실험을 바탕으로, 자외선 B 조사로 인한 세포독성 및 산화적 사멸을 억제하고 세포 내 항산화 기능을 강화시킬 수 있는 천연 항산화 피부보호 소재를 발굴하고자 하였다. 해양소재 추출물의 라디칼 소거능을 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay로 비교 측정한 결과 미역, 모자반, 다시마, 해마, 석결명, 모려, 해룡의 순으로 항산화력을 나타내었다. 이후 in vitro 세포 실험에서 자외선 B를 섬유아세포주인 HS68 세포에 노출시킨 경우 세포 독성이 유발되어 사멸이 진행되었으며 이는 모자반, 석결명, 청각, 해마 열수 추출물을 처리한 경우 현저히 억제되었다. 특히, 자외선 B로 인한 세포손상은 세포 내 활성산소종의 축적으로 인한 것임을 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA) 형광염색법으로 확인할 수 있었으며, 활성산소종의 생성은 모자반, 석결명, 청각, 해마 열수 추출물을 처리한 경우 유의적으로 감소되었다. 한편, 이러한 항산화 작용은 대표적인 내인성 항산화 효소인 catalase, superoxide dismutase 및 heme oxygenase-1의 발현 증가로 매개되었다. 이상의 결과는 모자반, 석결명, 청각, 해마 등의 해양소재가 항산화 작용을 통하여 산화적 스트레스가 매개하는피부손상과 노화과정을 예방 및 보호하는 새로운 화장품 천연소재로의 활용 가능성을 제시한다.

To develop natural antimicrobial agents for keeping qualities of postharvested greenhouse produce the antimiocrobial actions of Polygonum cuspidatum Sieb. et Zucc. extract , which showed remarkable antimicrobial effects against microorganism causing the postharvest decay of greenhouse produce, were investigate. In the inhibitory experiment of enzymes related to energy production metabolism hexokinase activities decreased to 73% and 68% by treating with Polygonum cuspidatum Sieb. et.Zucc. extract and Eugenia caryophyllata Thumnberg extract in comparison with control, respectively. Direct visualization of microbial cells by using both transmission electron microscope and scanning electron microscope showed that microbial cell membrane was destroyed by treating with the dilute extract solution. this change of celluloar membrane permeability could be identified in the experiment that 0-nitrophenyl--D-galactopyrano-side(ONPG), the artificial substrate of -galactosidase, was hydrolyzed in the presence of the extract, indicating that the membrane was perturbed. The separation and identification of the most antimicrobialo substances isolated from Polygonum cuspidatum Sieb et. Zucc. extract and Eugenia caryophyllata Thunberg extract were carried out by using gas chromatography and mass spectrometry 9GC/MSD), which were identified as eugenol. As a result, the functionality of Polygonum cuspidatum Sieb. et Zucc. extract and Eugenia caryophyllata Thunberg extract as antimicrobial agents for keeping qualities of postharvested greenhouse produce may be recommended.

Many plants collected at Japan, China, Korea, Imdonesia and South America were applied to antitumor and / or cytotoxic screening tests against Sarcoma 180 ascites in mice and / or V-79, KB, P388 cultured cells. On the course of these screening tests, alcoholic extracts of Forsythia viridissima (Oleaceae), Eurycoma longifolia(Simaroubaceae), Rubia cordifolia and R. akane(Rubiaceae), Cissampelos pareira and Abuta concolor (Menispermaceae), Nardostachys chinensis (Valerianacese), Mansoa alliaceae (Bignoniaceae), Casearia sylvestris (Flacourtiacear), Maytenus ilicifolia (Celastraceae), Hedychium coronarium (Zingiberaceae), Croton palanostigma(Euphorbiaceae), Cocculus trilobus(Menispermaceae), Ginkgo biloba(Ginkgoaceae), Alpinia galanga and Cucculus zanthorrhiza(Zingiberaceae), Evodia rutaecarpa(Rutaceae), and Periploca sepium(Asclepiadaceae) showed significant activity and their active principles were clarified. In this paper, a few antitumor substances in above plants are introduced.

Present anticancer drugs in the clinical side have not showed a conclusive effect of the chemotherapy for cancer patients. In order to find much more efficient antitumor agents fromnatural resources, various screening methods vivo and in vitro have been developed by manyresearchers. The intention of this paper is to provide an outline of some background on the tumorsystem in drug development of natural products, to review some screening programs for theevaluation of antitumor activity and to introduce the practical procedures of some antitumorscreening methods in vivo and in vitro. At the end of this paper, the current literatures related toantitumor natural products from higher plants at our laboratory are described.Key words'anticancer drugs, screening methods.