• The Plant Pathology Journal
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• 제20권2호
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• pp.81-84
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• 2004

Branched broomrape (Orobanche ramosa) is a holo-parasitic flowering plant that attaches to the root of its host, green plant, by means of a specialized structure known as haustorium. Following successful contact and penetration on susceptible plant root, complex tissue of Orobanche cells is formed which is known as the tubercle. Newly formed tubercles contain high activity ofindole-3-acetic acid (IAA). Triiodobenzoic acid (TIBA), as an inhibitor of IAA polar transport, was utilized to investigate the supply and requirement of auxin to the developing O. ramosa on tomato plant. There was no significant reduction in the incidence of O. ramosa per pot of different TIBA treatments. However, infection severity in terms of the number of O. ramosa shoots that emerged per plant and number of attachments per plant root system were significantly reduced by 60 % and 45 % on TIBA treated plants, respectively. Histo-logical studies revealed conspicuous delay in the initiation of xylem vessel differentiation inside tubercles of the TIBA treated tomato plants. Also, differentiated vessels showed thinner secondary wall deposition, and improper alignment within bundles inside those tubercles. They were wider and shorter in diameter in comparison to those of untreated plants. These findings were attri-buted to the short supply of IAA required for normal development, and to the xylem vessel differentiation of O. ramosa tubercles on infected tomato. Hence, this parasitic flowering plant seems to depend upon its host in its requirements for IAA, in a source to sink relation-ship.

• Archives of Pharmacal Research
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• 제29권6호
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• pp.490-496
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• 2006

This study aimed to evaluate in vitro effects of Rheum undulatum L. root on the development of dental caries, especially its effects on viability, dental plaque formation, and glycolytic acid production of Streptococcus mutans and Streptococcus sobrinus. Methanol extract of Rheum undulatum L. root and its fractions were prepared and tested. Among the test extract and fractions, dichloromethane fraction (DF) showed the most active antibacterial activity (inhibition zone: 13-17 mm) against S. mutans and S. sobrinus in a disc diffusion method. Minimal inhibitory concentrations (MICs) of DF against these bacteria ranged from 0.25 to 0.5 mg/mL. Furthermore, DF significantly inhibited the caries-inducing factors of these bacteria. At sub-MIC levels, DF inhibited in vitro dental plaque formation by S. mutans and S. sobrinus ($IC_{50}$= 0.079 and 0.142 mg/mL, respectively), which was caused, in part, by the inhibitory effect on the activity of glucosyltransferases. A significant reduction of glycolytic acid production was found at the concentration as low as 0.032 mg/mL for S. mutans and 0.063 mg/mL for S. sobrinus. The possible bioactive compounds that are inducing in vitro anti-cariogenic activity of DF are unknown. Based on the preliminary phytochemical analysis, the activity of DF may be related to the presence of anthraquinones, cardiac glycosides, coumarines, sterols/terpenes, and phenolics. These results indicate that DF is probably useful for the control of dental plaque formation and subsequent dental caries development.

• 한국자원식물학회지
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• 제31권3호
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• pp.211-217
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• 2018

Hibiscus syriacus (H. syriacus) as the national flower of Korea has been used as the herbal medicine in Asia. In this study, we evaluated the anti-inflammatory effect of 70% ethanol extracts from the root of Hibiscus syriacus (RHS-E70) and elucidated the potential signaling pathway in LPS-stimulated RAW264.7 cells. RHS-E70 dose-dependently suppressed NO production by inhibiting iNOS and IL-${\beta}$ expression in LPS-stimulated RAW264.7 cells. RHS-E70 inhibited the phosphorylation and degradation of $I{\kappa}B-{\alpha}$, which contributed to the inhibition of p65 nuclear accumulation and NF-${\kappa}B$ activation. Furthermore, RHS-E70 suppressed the phosphorylation of ERK1/2 and p38, which results in the inhibition of ATF2 phosphorylation and subsequent nuclear accumulation. These results indicate that RHS-E70 may exert anti-inflammatory activity by inhibiting NF-${\kappa}B$ and MAPK/ATF2 signaling. From these findings, RHS-E70 has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammatory diseases.

• International Journal of Industrial Entomology and Biomaterials
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• 제20권1호
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• pp.1-5
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• 2010

The studies have been conducted to control the soil borne fungal pathogens viz, Fusarium solani (Mart) Sacc. and Alternaria tenuissima the incitants of root rot and die-back diseases on mulberry stem cuttings planted in the mulberry nurseries and also in established mulberry gardens ten plant extracts with 10% concentration except Lantana camara (undiluted) were tested through poisoned food technique and four biofungicides were also screened by dual culture method under in vitro conditions. Plant extract of Prosopis juliflora showed the maximum inhibition on the mycelial growth (81.2% over A. tenuissima and 80.0% over F. solani) and followed by L. camara (66.7% over A. tenuissima and 68.9% over F. solani). Among the antagonists Pseudomonas fluorescens and Trichoderma viride showed maximum inhibition on the mycelial growth of both pathogenic fungi. The promising plant extracts (P. juliflora and L. camara) and antagonists (P. fluorescens and T. viride) were tested against both the pathogenic fungi under in vivo conditions along with the existing popular chemical Mancozeb. All the tested plant products and bio-fungicides showed inhibitory effect on both fungi. But the maximum survival percentage of mulberry cuttings was recorded in the treatment with T. viride (95% against F. solani and 90% against A. tenuisssima) followed by P. fluorescens (90% against both fungi) and T. harzianum (80% against F. solani and 85% against A. tenuisssima). Incase of the treatments with plant extracts and chemical fungicide the P. juliflora (60% against F. solani and 55% against A. tenuisssima) showed higher survival percentage and followed by L. camara (55% against F. solani and 50% against A. tenuisssima) and Mancozeb (55% against both fungi). In case of control only 10% of survival was recorded in F. solani inoculated cuttings and 15% survival in A. tenuissima inoculated cuttings.

• 생명과학회지
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• 제25권1호
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• pp.37-43
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• 2015

옥수수(Zea mays) 원뿌리에서 에틸렌 전구체인 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) 그리고 methyl jasmonate (MeJA)가 통기조직의 발달에 미치는 영향을 조사하였다. 식물호르몬 처리는 원뿌리의 종단 구성에 영향을 미치므로 control과 호르몬 처리된 뿌리의 비교 가능한 위치를 정할 필요가 있었다. 이를 위하여 원뿌리의 정단을 PR0, 기부를 PR100이라 정의하고 이 두 지점 사이를 길이에 비례하여 PR25, PR50, PR75로 구분하였다. 대조군 뿌리의 PR25와 PR50 부분에서는 통기조직이 관찰되지 않았으며 PR75 부분에서는 드물게 통기조직이 나타나기도 하였다. PR75 부위의 통기조직 면적은 ACC 또는 IAA가 존재할 때 증가하였다. 반면, MeJA는 옥수수 원뿌리가 침수되지 않았을 때와 침수되었을 때 서로 다른 차등 효과를 나타내었다. 뿌리가 침수되지 않았을 때 MeJA는 통기조직의 발달을 억제하였다. 반면, 뿌리를 침수 시키면 통기조직의 면적이 증가하는데 그 면적은 MeJA에 의하여 더욱 증가되었다. 한편, 곁뿌리 원기는 그 주변 피층세포의 통기조직 발달에 수반되는 세포사멸을 억제하는 것으로 알려져 있었다. 곁뿌리 원기에 의해 억제되는 통기조직의 발달은 위에 기술한 바와 같이 통기조직의 발달을 촉진하는 세 가지 호르몬들에 의해서도 회복되지 않았다. 이는 발달하는 곁뿌리 원기가 억제하는 통기조직 발달 조절의 세부 단계는 식물호르몬들이 작용한 이후 단계일 가능성을 보여주는 것이다.

• Weed & Turfgrass Science
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• 제2권3호
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• pp.242-247
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• 2013

현재 유기재배에서 잡초 방제를 위한 방법은 관행방법에 비해 효과적이지 못하다. 본 연구는 하늘타리의 잎, 줄기, 열매, 뿌리 추출물 중 어느 부위에서 제초 효과가 가장 높은지를 알아보기 위해서 각 부위별로 물, 열수 그리고 에탄올로 추출하였다. 또한 위의 추출방법 중 제초활성능력이 뛰어난 것을 hexane, chloroform, ethyl acetate, BuOH, $H_2O$로 용매분획하여 잠재적 제초 성분에 대한 특성을 조사하였다. 전반적으로 오이와 보리의 발아율, 초장 및 근장 억제는 추출방법 중 물 추출법이 가장 효과적이었고, 식물체 부위별로는 열매에서 가장 효과적이었다. Ethyl acetate, butanol, chloroform, hexane, water의 용매분획에서 오이와 보리의 발아율, 초장 및 근장 저해는 물 층에서 가장 좋았고 그 밖의 분획에서는 차이가 없었다. 5% 물 층 추출물 발아전 처리에 의해 바랭이와 까마중의 생장량은 80~100% 억제되었으나, 이 추출물에 의한 오이와 보리뿐만 아니라 잡초종(바랭이, 까마중 등) 경엽처리에 의한 생육저해 효과는 없었다. 본 연구결과로 볼 때 하늘타리 추출물을 친환경 또는 유기농 재배에 잡초방제를 위해 사용할 수 있을 것으로 본다.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.149-158
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• 2009

American sycamore seedlings were grown in chambers with two different ozone concentrations ($O_3$-free air and air with additional $O_3$) for 45 days. Both the control and the $O_3$ chambers included non-fertilized and fertilized plants. After 18 days of $O_3$ fumigation, seedlings were placed in a clean chamber for 27 days. Seedlings under ozone fumigation showed a significant decrease in pigment contents and photosynthetic activity, and a significant increase in lipid peroxidation. Fertilization enhanced physiological damage such as the inhibition of photosynthetic activity and the increase of lipid peroxidation under ozone fumigation. During the recovery phase, the physiological damage level of seedlings increased with ozone fumigation. In addition, physiological damage was observed in the fertilized seedlings. Superoxide dismutase (SOD) and glutathione reductase (GR) activities of $O_3$-treated seedlings increased up to 33.8% and 16.3% in the fertilized plants. The increase of SOD activity was higher in the fertilized plants than in the non-fertilized plants. Negative effects of ozone treatment were observed in the biomass of the leaves and the total dry weight of the fertilized sycamore seedlings. The $O_3$-treated seedlings decreased in stem, root and total dry weight, and the loss of biomass was statistically significant in the fertilized plants. In conclusion, physiological disturbance under normal nutrient conditions has an effect on growth response. In contrast, in conditions of energy shortage, although stress represents a physiological inhibition, it does not seem to affect the growth response.

• Preventive Nutrition and Food Science
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• 제10권2호
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• pp.172-178
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• 2005

Dandelions have been reported to have medicinal properties and bioactive components that impact human health. However, the precise biological properties of dandelions and the parts of the plants possessing bioactive components remain uncertain. In this study, we evaluated 3 different types of dandelions based on their cultivation origin (Songpa, Uiryung, and native Uiryung types) as well as their 4 different plant parts (leaf, flower, root, skin). Each sample was extracted with $80\%$ methanol and then compared for the biological activities (anti-oxidative, immune cell proliferative and tumor cell growth inhibitory activities). All 3 types of dandelions possessed a degree of biological functions including the hydroxyl radical scavenger activity, immune cell proliferative activity and tumor cell growth inhibitory activity. However, there was no significant difference in these activities between the 3 dandelion types. Leaves of all three dandelion types showed the highest levels of all biological activities. To a lesser degree, the flower and root parts displayed biological activities. In the skin parts, anti-oxidative activity was also detected only at higher doses of dandelion extracts. Heating the dandelion leaf extract did not affect the biological activity, suggesting a heat-stable nature of the biological compounds. Taken together, these collective data suggest that dandelions, in particular their leaves, possess a high concentration of heat-resistant biological compounds, which are responsible for anti-oxidative, immune cell proliferative and tumor cell growth-inhibitory activities.

• 생명과학회지
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• 제22권5호
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• pp.681-686
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• 2012

빛이 굴중성과 뿌리 생장에 미치는 영향을 알아보기 위해 Arabidopsis phytochrome mutant를 이용하여 뿌리 생장과 굴중성 반응을 측정하였다. $PhyA$의 뿌리 생장은 white light를 제외한 모든 빛 조건에서 WT와 비교하여 촉진되었다. 특히 red light에서 키웠을 때 다른 mutant와는 달리 뿌리 생장이 촉진되었다. 반면에 phyB는 모든 빛 조건에서 키웠을 때 뿌리 생장이 억제되었으며, 특히 double mutant인 $phyAB$는 white light와 red light에서 키웠을 때 뿌리 생장이 가장 많이 억제되었다. $PhyA$의 굴중성 반응은 far-red light에서 키웠을 때를 제외하고 모든 빛 조건에서 키웠을 때 WT와 비교하여 촉진되었다. 한편 $phyAB$는 모든 조건에서 모두 굴중성 반응이 억제되었다. Ethylene 생합성을 조절하는 효소인 ACS transcript 수준은 white light와 red light에서 키웠을 때 $phyA$가 높게 나타났으며, far-red light에서 키웠을 때는 $phyA$의 transcript 수준이 억제되었다. 결론적으로 뿌리 생장과 굴중성 반응은 $phyB$의 $P_{fr}$에 의해 조절된다.

• Journal of Nutrition and Health
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• 제49권4호
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• pp.233-240
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• 2016

항산화, 항암 및 항염증 효능 등의 생리 활성이 보고된 우엉 뿌리의 열수 추출물을 제조하여 advanced glycation end products (AGEs) 형성 저해 효과를 확인하였다. AGEs는 bovine serum albumin (BSA)과 단당류인 glucose, fructose, galactose를 혼합하여 $37^{\circ}C$에서 3주간 배양하여 생성하였고 매주 형광도 측정, fructosamine 분석, ${\alpha}$-dicarbonyl compounds 함량 분석을 통해 AGEs의 생성량을 확인하였다. 우엉 뿌리 추출물의 AGEs 생성 저해능을 AGEs 생성 억제제로 알려져 있는 aminoguanidine (AG)의 저해능과 비교하였다. 우엉 뿌리 추출물은 BSA와 단당류인 glucose, fructose, galactose 각각의 당화반응을 억제하였으며 특히 배양 3주차에서 BSA와 glucose의 당화반응 결과물인 AGEs 생성을 유의적으로 저해하였다. 농도 2 mg/mL 이상의 우엉 뿌리 추출물은 1 mM AG보다 AGEs 생성 저해능이 우수하였으며 농도 4 mg/mL의 우엉 뿌리 추출물은 배양 3주차에서 AGEs 생성을 약 80% 이상 억제하는 효능을 나타냈다. 체내 혈당은 당뇨병과 같은 질환과 식이의 영향을 받으므로 다양한 glucose 농도에서 우엉 뿌리 추출물의 AGEs 생성 억제능을 조사하였다. 그 결과 AGEs 생성은 glucose의 농도에 비례하여 증가하였으며 우엉 뿌리 추출물은 당뇨환자의 식후에 관찰되는 혈당인 25 mM glucose 군에서 1 mM의 AG보다 높은 우수한 저해 효과를 확인하였다. 본 연구 결과는 우엉 뿌리 추출물의 AGEs 생성 억제라는 새로운 기능성을 밝히며 향후 당뇨 합병증 예방 효능을 가진 기능성 식품으로의 개발 가능성을 제시한다.