• International Journal of Industrial Entomology and Biomaterials
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• 제45권2호
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• pp.43-48
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• 2022

Bombyx mori is a representative industrial insect and is used in silk production. Additionally, it serves as an insect model in molecular studies. To date, various molecular studies on its physiological characteristics, including the innate immune response and cuticular melanization, have been conducted. The melanization, including cuticular melanization, in insects is controlled by the prophenoloxidase-activating system, which is also involved in their innate immune response. In this review, to better understand the molecular mechanisms underlying the prophenoloxidase-activating system in the silkworm, the roles of five biomolecules, namely tyrosine hydroxylase, prophenoloxidase-activating enzyme, phenoloxidase, serine protease homolog, and immulectin, are discussed.

• Molecules and Cells
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• 제26권6호
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• pp.606-610
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• 2008

Phenoloxidase (PO), a melanin-forming enzyme around the foreign bodies, is an important component of the host defense system in invertebrates. Pro-PO is the enzymatically inactive zymogen form of PO. In the Drosophila genome, three Pro-PO isoforms have been identified to date. These include Pro-PO1 and 2, which are primarily expressed in crystal cells, and Pro-PO3, which is predominantly found in the lamellocytes. In this study, we demonstrated that Drosophila Pro-PO3, but not Pro-PO1 or 2, is enzymatically active in its zymogen form. These findings were evidenced by spectacular melanin forming capacities of various cells and tissues that overexpressed these pro-enzymes. Furthermore, the melanization phenotype observed in the lamellocyte-enriched $hop^{Tum-l}$ mutant was drastically reduced in the absence of PPO3, indicating that PPO3 plays a major role in the lamellocyte-mediated spontaneous melanization process. Taken together, these findings indicate that the biochemical properties, activation mode and in vivo role of Pro-PO3 are likely distinct from those of the other two Pro-PO enzymes involved in Drosophila physiology.

• The Plant Pathology Journal
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• 제19권2호
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• pp.92-96
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• 2003

The study was conducted to determine the cultural conditions and the effect of inert fillers for melanization and sporulation abilities of sodium alginate pellets, and the weeding efficacy of the formula in the field. Melanin production of E. nematosporus was affected by striking frequency. Percentage of melanized beads was increased to 80.6% at higher rpm up to 180. The melanized pellets produced more conidia with abundant mucilage than unmelanized pellets. Shaker culture of Epicoccosorus nematosporus with sodium alginate yielded a total of 55 mg per 100 pellets. Percentage of melanized pellets was highest with 81.0% and 83.3% of melanization, when wheat bran and rice polish were amended and produced the conidia with 65.4 and 68.4 mg per 100 pellets, respectively. When 1 L of conidial suspension of 6.0$\times$$10^5$ conidia per ml was applied on 30-day-old plants in a plot, 74.5% of the plants were killed within 20 days, whereas, its melanized sodium alginate pellets killed 57.8% of the plants in the same period. The number of tuber formation of Eleocharis kuroguwai in the untreated control plots was 128.5 per plot, but those of the plots treated with conidial suspension and melanized pellets were 22.1 and 39.7, respectively, at the end of the season. Results of this study showed that melanization of mycelia-mixed sodium alginate are an important sporulation factor in E. namatosporus as a mycoherbicide.

• 약학회지
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• 제46권1호
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• pp.75-80
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• 2002

Quercetin is one of the bioflavonoid compounds and has multiple biological effects such as antioxidant and effective anti-inflammatory agent. Melanin has an important role in protecting human skin from the damaging effects of ultra-violet W) radiation. We studied the effect of quercetin on proliferation of B16/F10 melanoma cells. After 48h treatment of cells with quercetin, the cells exhibited a dose-dependent inhibition in their proliferation without apoptosis. Therefore, the decrease in cell numbers may be due to cell growth arrest, not due to cell death by cytotoxicity. We also investigated the effect of quercetin on melanogenesis of this cells. B16/F10 melanoma cells were grown for 48h in the presence of 0.01~50$\mu\textrm{g}$/ml quercetin and the total melanin contents were measured. Quercetin stimulated melanization of the cells in low concentrations (0.01~20$\mu\textrm{g}$/ml), whereas it inhibited melanization in high concentrations (30~50$\mu\textrm{g}$/ml). It was observed that quercetin differently regulates melanogenesis of B16/F10 melanoma cells dependent on its concentrations.

• The Plant Pathology Journal
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• 제17권4호
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• pp.210-215
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• 2001

The phenotype of Rhizoctonia solani KR-13 was randomly segregated to both melanin-producing (M+) and non-producing (M-) types through successive cultures on PDA. M+type with dark melanin showed strong pathogenicity to rice and self-anastomosis. Meanwhile, M- type with white or less-melanized mycelia showed very weak pathogenicity and non-self-anastomosis. Melanin production of R. solani was affected by incubation temperature in both M+ and M- types, but not by light treatment. The application of tricyclazole, an inhibitor of fungal melanin biosynthesis, showed no controlling effect on R. solani causing rice sheath blight. Results of this study showed that melanization of mycelia of R. solani is an important pathogenicity factor in rice.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2002년도 합동 춘계 학술발표회
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• pp.96-96
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• 2002

• 대한임상검사과학회지
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• 제53권4호
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• pp.363-370
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• 2021

본 연구는 중금속화합물인 초산납(LA)의 피부독성을 B16/F10 멜라닌세포를 배양하여 조사하였으며, LA의 독성에 대한 싸리나무(Lespedeza bicolor, LB) 추출물의 보호효과를 조사하였다. 본 연구를 위하여 세포생존율을 비롯하여 항산화능 분석인 전자공여능(EDA)활성 억제능과 총 멜라닌량 저해능을 조사하였다. 그 결과 LA는 배양 세포에 처리한 농도 의존적으로 세포생존율을 유의하게 감소시킴으로써 독성을 나타냈다. 이 때 XTT₅₀값은 52.7 µM로서 고독성(highly-toxic)인 것으로 나타났다. 한편, 항산화제인 kaempferol (KAE)은 LA의 독성에 손상된 세포생존율을 유의하게 증가시켰다. 또한, LA의 독성에 대한 LB 추출물의 보호효과에 있어서, LB 추출물은 LA만의 처리에 비하여 세포생존율을 유의하게 증가시켰으며, 이와 동시에 전자공여능(EDA) 활성 억제능과 멜라닌 저해능과 같은 항산화 효과 및 멜라닌화의 억제를 나타냈다. 이상의 결과로부터 LA의 독성에 산화적 손상이 관여하고 있으며, LB 추출물은 항산화와 멜라닌화의 저해 효과에 의하여 LA의 독성을 효과적으로 방어하였다. 따라서, LB 추출물과 같은 천연물질은 LA와 같이 산화적 손상과 관련이 있는 중금속화합물의 독성방어나 또는 멜라닌화로 인한 질환을 위한 치료 및 간호중재 보완물질로 개발할 가치가 있다고 생각된다. 본 연구결과를 기반으로 산화적 손상이 원인인 질환에 LB 추출물을 적용가능한 형태 및 방법에 대해 추가 연구가 필요함을 제언한다.

• The Plant Pathology Journal
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• 제24권4호
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• pp.407-416
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• 2008

Studies were conducted to determine the effects of temperature, solute potential and carbon source on the mycelial growth, sclerotia development, and apothecium production of an isolate of Sclerotinia sclerotiorum. Mycelial growth rate was greatest at $25^{\circ}C$ on potato dextrose agar (PDA) medium amended with up to 2% NaCl (${\psi}s{\leq}1.91\;MPa$) and thereafter, growth rate declined. The least number of sclerotia were produced at $20^{\circ}C$on both PDA and malt extract agar (MEA) amended with 8% NaCl (${\psi}s=6.62\;MPa$). With increasing temperature and decreasing solute potential the number and size of sclerotia were significantly reduced. The combined effect of temperature, solute potential and carbon source on sclerotia production were highly significant and had an impact on the development of the rind layer cells of sclerotia. These cells lacked a transparent cell wall which was surrounded by a compact melanized layer, and some of these cells appeared to be devoid of cell contents or were totally vacuolated. The survival of the sclerotia with increase in salinity and temperature appeared to affect melanization and the nature of the rind cells. The observations of this study re-enforces the need for an integrated disease management to control S. sclerotiorum.

• 대한화학회지
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• 제44권6호
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• pp.533-540
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• 2000

음양곽 물추출액과 $\alpha$-melanocyte stimulating hormone ($\alpha$-MSH)에 의한 B16 melanoma 세포의 멜라닌화를 비교 조사하였으며, retinoic acid (RA)에 의한 억제효과도 연구하였다. B16 melanoma 세포(1×$10^5$개 정도)를 $\alpha$-MSH로 처리하고 72시간 배양한 결과 $\alpha$-MSH 처리농도에 비례하여 tyrosinase 활성도와 melanin 생성이 증가되었으며, 8 ng/mL 처리시 tyrosinase 활성도는 350%, melanin 함량은 290% 이상이었다. 음양곽 물추출액으로 처리한 경우에는, 100 ${\mu}g$/mL 처리시 tyrosinase 활성도는 200%, melanin 함량은 180% 이상이었다. 위 조건에 RA를 가하면, $\alpha$-MSH의 경우 tyrosinase 활성도는 350%에서 210%로, melanin 함량은 290%에서 250%로 억제되었다. 음양곽 물추출물의 경우 tyrosinase 활성도는 200%에서 100%로, melanin 함량은 180%에서 120%로 억제되었다. 이 결과는 음양곽 물추출액이 cAMP 신호전달 경로를 통하여 B16 melanoma 세포의 멜라닌화를 촉진하며, RA는 그것을 억제하는 것으로 해석된다.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.611-616
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• 2003

Korean ginseng(Panax Ginseng C.A. Meyer) known as a oriental miracle drug is an important medicinal plant. Ginseng has been used for geriatric, tonic, stomachic, and aphrodisiac treatments for thousands years. Also, it is an antibiotic and has therapeutic properties against stress and cancer. Ginseng is widely distributed all over the world. Among them, Korean mountain ginseng has the most valuable effect on pharmaceuticals. The roots of mountain ginseng contained several kinds of ginsenosides that have many active functions for the human body. However, the study of mountain ginseng has a limit because the mountain ginseng is very expensive and rare. So, we artificially cultured mountain ginseng adventitious roots using the bioreactor culture system. We induced callus from original mountain ginseng, directly dug up in mountain and aged about one hundred ten years. Separated adventitious roots were precultured in 500ml conical flasks and then, transferred in 20L bioreactors. The adventitious roots of mountain ginseng were harvested after culturing for 40days, dried and then, extracted with several solvents. In this study, we investigated the whitening effect, anti-wrinkle effect and the safety of tissue cultured adventitious roots extract of mountain ginseng in order to identify the merit as a cosmetic ingredient. Particularly, extract of mountain ginseng adventitious roots showed whitening and anti-wrinkle effects. The inhibitory effect of this extract on the melanogenesis was examined using B-16 melanoma cell. When B-16 melanoma cells were cultured with adventitious root extract, there was a dramatically decrease in melanin contents of 8-16 melanoma cell. And we identified this extract inhibited Dopa auto-oxidation significantly. Also, when transformed mouse fibroblast L929 cells were treated with this extract, there was a significant increase in collagen synthesis. The results show significant inhibited melanization and wrinkle without inhibiting cell viability.