• Journal of Life Science
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• 제11권2호
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• pp.103-107
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• 2001

The equine chorionic gonadotropin (eCG) subunits $\alpha$ and ${\beta}$ are transcribed from different genes and associate noncovalently to form the bioactive eCG heterodimer. Dimerization is rate limiting for eCG secretion, and dissociation leads to hormone inactivation. The correct conformation of the heterodimer is alto important for efficient secretion, hormone-specific post-translational modifications, receptor binding and signal transduction. To determine whether ${\alpha}$ and ${\beta}$ subunits can be synthesized as a single polypeptide chain (tethered-eCG) and also display biological activity, the tethered-eCG molecule by fusing the carboxyl terminus of the eCG ${\beta}$-subunit to the amino terminus of the af-subunit was construe-ted and transfected into chinese hamster ovary (CHO-Kl) cells. LH- and FSH-like activities were assayed in terms of testosterone production and aromatase activity in primary cultured rat Leydig cells and granulosa cells, respectively. The tethered-eCG was efficiently secreted and showed similar LH-like activity to the dimeric eCG ${\alpha}$/${\beta}$ and native eCG. FSH-like activity of the tethered-eCG was also shown similarly in comparison with the native and wild type eCG ${\alpha}$/${\beta}$. Our data for the first time suggest that the tethered-eCG can be expressed efficiently and the produced product by the CHO-K1 cells is fully LH- and FSH-like activities in rat in vitro bioassay system. Our results also suggest that this molecular can imply particular models of FSH-like activity not LH-like activity in the eCG. Taken together, these data indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion.

• Journal of Microbiology
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• 제45권5호
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• pp.388-393
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• 2007

Citrus variegated chlorosis (CVC) is a disease of the sweet orange [Citrus sinensis (L.)], which is caused by Xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that has been shown to infect all sweet orange cultivars. Sweet orange trees have been occasionally observed to be infected by Xylella fastidiosa without evidencing severe disease symptoms, whereas other trees in the same grove may exhibit severe disease symptoms. The principal endophytic bacterial species isolated from such CVC-asymptomatic citrus plants is Curtobacterium flaccumfaciens. The Madagascar periwinkle [Citrus sinensis (L.)] is a model plant which has been used to study X. fastidiosa in greenhouse environments. In order to characterize the interactions of X. fastidiosa and C. flaccumfaciens, periwinkle plants were inoculated separately with C. flaccumfaciens, X. fastidiosa, and both bacteria together. The number of flowers produced by the plants, the heights of the plants, and the exhibited disease symptoms were evaluated. PCR-primers for C. flaccumfaciens were designed in order to verify the presence of this endophytic bacterium in plant tissue, and to complement an existing assay for X. fastidiosa. These primers were capable of detecting C. flaccumfaciens in the periwinkle in the presence of X. fastidiosa. X. fastidiosa induced stunting and reduced the number of flowers produced by the periwinkle. When C. flaccumfaciens was inoculated together with X. fastidiosa, no stunting was observed. The number of flowers produced by our doubly- inoculated plants was an intermediate between the number produced by the plants inoculated with either of the bacteria separately. Our data indicate that C. flaccumfaciens interacted with X. fastidiosa in C. roseus, and reduced the severity of the disease symptoms induced by X. fastidiosa. Periwinkle is considered to be an excellent experimental system by which the interaction of C. flaccumfaciens and other endophytic bacteria with X. fastidiosa can be studied.

• 한국약용작물학회지
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• 제6권3호
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• pp.204-209
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• 1998

오디의 기능성(機能性) 식품개발을 위한 기초연구(基礎硏究)의 일환으로 뽕나무 품종에 따라 9종의 오디를 채취(採取)하여 냉동건조(冷凍乾燥)한 후 각각에 대하여 항염증 및 항산화효과를 검색하였다. 그 결과를 요약하면 다음과 같다. 1. 비스테로이드성 항염증 작용을 검색하기 위하여 cyclooxygenase II의 활성억제도를 측정하였다. 그 결과 신광뽕 > 검설뽕 > 4배성 휘카스 > 2배성 휘카스 >검설뽕 등의 순으로 억제 효과를 나타냈다. 현재 항염증제의 표준물질로 사용되고 있는 nabumetone 10ppm에서 활성억제도(活性抑制度)를 1이라 했을 때, 가장 높은 억제 활성을 나타낸 신광뽕 오디의 경우는 0.55의 활성도를 나타냈다. 2. 최근에 천연물(天然物)로부터 항암작용과 더불어 소염작용을 갖는 물질을 탐색하기 위하여 phosphlipase $A_2$의 활성억제도법을 이용한다. 오디 9품종의 MeOH 추출물 $100{\mu}g/ml$의 농도에서 phospholipase에 대한 억제활성은 신광뽕 > 검설뽕 > 휘카스 > 북산2호의 순으로 억제작용을 나타냈다. 3. 항염증 작용과 항산화 작용은 연관성이 높기 때문에 DPPH법을 이용하여 radical scavengingrate를 측정했다. 그 결과 신광뽕 > 검설뽕 > 휘카스 > 청일뽕의 순으로 항산화작용을 나타냈다. 결론적으로 9종의 오디품종중 항염증제로의 이용가능성이 있는 것은 검설뽕, 휘카스 및 신광뽕이었고, 북산2호와 대도상의 항산화 항염증 효과는 전혀 없었다.

• 한국응용곤충학회지
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• 제31권2호
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• pp.182-189
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• 1992

신규 설충성물질 개발의 전제조건이 되는 용매의 선택을 위하여, 아세톤의 9종의 유기용매를 수종의 곤충에 대한 독성과 식이식물 및 화합물의 용해성에 미치는 영향을 엽침지법과 분무법으로 평가하였다. 각종 용매의 공시충에 대한 치사독성과 용매의 이화학적인 성질과는 뚜렷한 상관관계가 보이지는 않았으나, 분무법 처리시 벼멸구의 경우 밀도가 높을수록, 배추좀나방의 경우에는 증기압이 낮을수록 공시충에 대한 치사독성이 높았으나, 비등점, 쌍극자모멘트, 유전율, 표면장력, 점도와는 상관관계를 보이지 않았다. 처리 방법에 있어서는 분무처리가 엽침지법보다 더 높은 치사독성을 나타내었다. 약해와 용매의 이화학적 성상 역시 명확한 상관관계를 보이지 않았으나, 엽침지법의 경우 수도에 있어서 유전율이 낮을수록 약해가 심하였으며, 분무법 처리시에는 쌍극자 모멘트가 높을수록 약해가 심하였으나 기타의 이화학적 성상과는 상관관계를 보이지 않았다. 엽침지처리가 분무처리에 비하여 강한 약해를 유발하였다. 합성 화합물과 식물체 메탄올 추출물은 아세톤에 대한 용해성이 양호하여 생물검정시 5% 아세톤수용액이 다량의 화합물을 검정하는데 적합하였다.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1733-1736
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• 2006

A new biologically active peptide with structural similarity to neuromedin N (NMN) has been isolated from extracts of visceral tissue of the African lungfish, Protopterus dolloi, using the rectum of the quail as the bioassay system. The primary structure of NMN-related peptide was established as Lys-Ala-Pro-Tyr-Ile-Leu-OH ([$Ala_2$]-NMN) and contained one substitution ($Ala_2\rightarrow$Ile) compared with the porcine NMN. [$Ala_2$]-NMN was found to have an excitatory effect on rectal muscle tissues of quail (Coturnix japonica), newt (Cynops pyrrhogaster) and black bass (Micropterus sulmoides). The threshold concentration of [Ala2]-NMN for contraction of C. japonica muscle was found to be approximately $10^-11$M. [$Ala_2$]-NMN showed contractile activities in the following order: C. japonica > C. pyrrhogaster > M. sulmoides. The identification of [Ala2]-NMN provides evidence that NMN family, hitherto confined to mammals, has a widespread occurrence in lungfish.

• Macromolecular Research
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• 제11권5호
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• pp.334-340
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• 2003

In order to fabricate new sustained delivery device of nerve growth factor (NGF), we developed NGF-loaded biodegradable poly(L-lactide-co-glycolide) (PLGA, the mole ratio of lactide to glycolide 75:25, molecular weight: 83,000 and 43,000 g/mole, respectively) film by novel and simple sandwich solvent casting method for the possibility of the application of neural tissue engineering. PLGA was copolymerized by direct condensation reaction and the molecular weight was controlled by reaction time. Released behavior of NGF from NGF-loaded films was characterized by enzyme linked immunosorbent assay (ELISA) and degradation characteristics were observed by scanning electron microscopy (SEM) and gel permeation chromatography (GPC). The bioactivity of released NGF was identified using a rat pheochromocytoma (PC-12) cell based bioassay. The release of NGF from the NGF-loaded PLGA films was prolonged over 35 days with zero-order rate of 0.5-0.8 ng NGF/day without initial burst and could be controlled by the variations of molecular weight and NGF loading amount. After 7 days NGF released in phosphate buffered saline and PC-12 cell cultured on the NGF-loaded PLGA film for 3 days. The released NGF stimulated neurite sprouting in cultured PC-12 cells, that is to say, the remained NGF in the NGF/PLGA film at 37 $^{\circ}C$ for 7 days was still bioactive. This study suggested that NGF-loaded PLGA sandwich film is released the desired period in delivery system and useful neuronal growth culture as nerve contact guidance tube for the application of neural tissue engineering.

• Journal of Ginseng Research
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• 제44권2호
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• pp.215-221
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• 2020

Background: Panax ginseng has been used for a variety of medical purposes in eastern countries for more than two thousand years. From the extensive experiences accumulated in its long medication use history and the substantial strong evidence in modern research studies, we know that ginseng has various pharmacological activities, such as antitumor, antidiabetic, antioxidant, and cardiovascular system-protective effects. The active chemical constituents of ginseng, ginsenosides, are rich in structural diversity and exhibit a wide range of biological activities. Methods: Ginsenoside constituents from P. ginseng flower buds were isolated and purified by various chromatographic methods, and their structures were identified by spectroscopic analysis and comparison with the reported data. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H- tetrazolium bromide method was used to test their cytotoxic effects on three human cancer cell lines. Results: Six ginsenosides, namely 6'-malonyl formyl ginsenoside F₁ (1), 3β-acetoxyl ginsenoside F₁ (2), ginsenoside Rh₂₄ (6), ginsenoside Rh₂₅ (7), 7β-hydroxyl ginsenoside Rd (8) and ginsenoside Rh₂₆ (10) were isolated and elucidated as new compounds, together with four known compounds (3-5 and 9). In addition, the cytotoxicity of these isolated compounds was shown as half inhibitory concentration values, a tentative structure-activity relationship was also discussed based on the results of our bioassay. Conclusion: The study of chemical constituents was useful for the quality control of P. ginseng flower buds. The study on antitumor activities showed that new Compound 1 exhibited moderate cytotoxic activities against HL-60, MGC80-3 and Hep-G2 with half inhibitory concentration values of 16.74, 29.51 and 20.48 μM, respectively.

• 생약학회지
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• 제36권3호통권142호
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• pp.240-244
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• 2005

The methanol extract of the seed of Myristica fragrans (myristicaceae) demonstrated a potent inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2(melanoma), XF498 (central nerve system) and HCT-15(colon). The MeOH extract was fractionated into three portions by serial solvent partition i,e., EtOAc soluble part, BuOH soluble part and remaining water layer. Among them, the EtOAc soluble part of the extract demonstrated a potent inhibition on the proliferation of cultured human tumor cells, Bioassay-guided fractionation of the EtOAc soluble part led to the isolation of six lignan constituents, i.e., safrole(1), machilin A (2), licarin B (3), macelignan (4), mesodihydroguaiaretic acid (5) and myristargenol A (6) as well as a large amount of myristic acid as active ingredients. Structures of the isolated active components (1-6) were established by chemical and spectroscopic means.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.49-49
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• 2020

Bacterial leaf blight (BLB), caused by X. oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice due to its high epidemic potential. Understanding BLB resistance at a genetic level is important to further improve the rice breeding that provides one of the best approaches to control BLB disease. In the present investigation, a total of 10,000 accessions of rice germplasm were tested to resistance degree of four Korean isolated races (K1, K2, K3 and K3a) of Xoo by bioassay and a diverse 268 accessions was selected to the genome-wide association study (GWAS) using high quality 34,724 SNPs to identify the associated with resistance loci. LOC_Os04g53160 of chromosome 4 was significantly associated with K1 race resistant. LOC_Os11g46230 and LOC_Os11g47150 of chromosome 11 were highly associated with K2 and K3 races as 23.7 and 27.4 of -log(P) value, but K3a resistant loci was weakly associated at LOC_Os03g55270 of chromosome 3. The results of the GWAS validate known gene of BLB resistant and identified novel loci of R genes that provide useful targets for further investigation to help the breeding system and identified gene and QTL provide valuable sources for further functional characterization.

• Parasites, Hosts and Diseases
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• 제36권1호
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• pp.15-22
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• 1998

Strongyloides venezuelensis을 자유생활형 유충을 얻고자, 쥐의 분변 물질을 첨가한 영양 배지를 polyvinyl bag에 넣어 배양하는 배양기술을 확립하였다 포화식염수법으로 회수한 충란의 부화율은 배양 온도에 따라서 다르게 관찰되었는데 (Y = $-0.192X^2$ + 8.673x - 19.550, r = 0.901) $^25{\circ}C$에서 100% 부화율을 나타내었지만 온도가 낮거나 높아도 감소되는 양상을 나타내었다. 회수 한 충란 $^20{\circ}C$에서 5일간 관찰하였을 때 자유생활형 유충으로의 발육률은 영양 배지의 농도를 증가시키면 증가하여 0 12%에서 최고치를 보이다가 다시 낮아지는 양상을 보여 (Y = $-864.032X^2$ + 245.995X - 0.560, r = 0.875), 감염형 3기 유충($L_3$)으로의 발육률은 배양 온도에 따라서 다르게 관찰되었다 즉, $^25{\circ}C$에서 가장 높아서 20%에 달하며 $15^{\circ}C$는 10.9%, 그리고 $^20{\circ}C$에서는 18.1%로 나타났다 (Y = $-0.189X^2$ + 8.387x - 72 795 r = 0.981). 그렇지만 감염 유충으로 성장하는데 필요한 기간도 역시 온도의 변화와 관련이 있어 온도가 높으 면 높을수록 소요되는 시간이 잔게 나타났다 (Y = $0.035X^2$ - 2.025X + 32.375, r = 0.995) 이상의 결과로 미루어 보아 감염 유충의 최대 회수율 (19.2%)은 15,000개를 polyvinyl bag에 0.12% 영양 배지와 더불어 $^25{\circ}C$에서 5일간 배양하였을 때 얻을 수 있었다. 이처럼 새로이 고안한 Skonavloides 속의 기생충 배양 기술은 화학 물질, 구충제, 제초제에 대한 선별검사와 기생충과 관련된 면역학적 연구에 생물학적 도구로서 사용될 수 있을 것으로 기대된다. 저자는 S. venezuelensis의 국문 이름을 베네수엘라분선충으로 제안한다.