• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.257-275
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• 1984

Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.149-154
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• 1996

Effects of various kinds of sawdusts, supplements and culture conditions on activities of several enzymes such as protease, phenoloxidase and cellulase produced from mycelium of P. ostreatus grown on sawdust medium were studied and the results are as follows; Higher specific activity of these enzymes was observed when oak tree sawdust and poplar tree sawdust were supplemented with rice bran or wheat bran at rate of 30%, 20% and 10% in total volume respectively. Higher total activities of protease, phenoloxidase and cellulase were observed at 70% of the moisture contents of culture media, while lower activity of these enzymes was observed with 40% moisture contents of sawdust culture medium. The pH 4 and 9 of the sawdust media appeared to be optimum pH for the. production of protease while pH 5 and 7 were optimal for the production of phenoloxidase. The pH 6 of the sawdust medium was optimal for the production of cellulase. The optimum incubating temperature for the production of protease, phenoloxidase and cellulase was $25^{\circ}C$. Higher total activities of protease and phenoloxidase were observed when culture medium was added with wood vinegar at the control, and 0.5% for cellulase.

• The Microorganisms and Industry
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• v.14 no.3
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• pp.12-14
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• 1988

빛에 의한 생물체의 분화는 작용파장별로 분류 할 때 고등식물에서 흔히 나타나는 붉은 빛에 의한 분화와 곰팡이류에서 볼 수 있는 푸른빛에 의한 것 두 종류가 있다. 곰팡이는 Chlorophyll이나 Phytochrome이 없어 붉은ㅅ개 파장을 흡수하는 phytochrome에 의한 분화는 없으나 푸른색은 곰팡이의 생활사에 중요한 요인이 된다. 예를 들면 Phycomyces와 Trichoderma의 photophorogenesis, Cyathus와 Coprinus의 fruiting body형성, Poycomyces와 Neurospora의 photocarotenogenesis, Phycomyces와 Pilobolus의 phototropism등 곰팡이의 metabolism과 development가 푸른 빛에 의하여 영향을 받는다. 한편 곰팡이의 포자및 포자생성기관은 녹색, 갈색, 흑색 등 phenoloxidase의 산물인 melanin 색소를 가지는 경우가 많으며 그 예로는 Podospora, Schizophyllum, Aspergillus 등과 같이 reproduction 할 때 phenoloxidase가 직접적 혹은 간접적으로 연관되어 있다. 버섯형성균류의 하나인 Coprinus congregatus는 버섯형성과정에서 빛을 필요로 하며 이때 phenoloxidase가 어떠한 역할을 하는지 실험하였다.

• BMB Reports
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• v.34 no.1
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• pp.15-20
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• 2001

One of the innate immune reactions in invertebrates is the pro-phenoloxidase (pro-PO) activation system that is involved in the generation of superoxide, melanin synthesis, and the subsequent sequestration of foreign matter entering the hemocoel of the invertebrates. However, the molecular mechanism of this biological reaction is still obscure. To expand our understanding of the biological roles of the pro-PO activation system in invertebrates, we performed a yeast two-hybrid screening by using three regions of pro-PO as bait and a yeast two-hybrid cDNA library from Tenebrio molitor larvae as prey We isolated a novel partial cDNA clone that encodes a glycine-rich protein that interacted with the active phenoloxidase (termed phenoloxidase interacting protein, POIP). POIP consists of two domains: One is an N-terminal unique domain and the other is a C-terminal glycine-rich domain. The C-terminal glycine-rich domain showed sequential homology with those of insect antifungal proteins. Also, the yeast two-hybrid screen in a reverse orientation (using POIP as bait) yielded PO, suggesting that the PO-POIP interaction is specific. By using a 315 bP PCR fragment of the N-terminal unique region of POIP, we cloned the full-length cDNA of POIP from the Tenebruo cDNA library constructed by using E. coli injected larvae. The interaction analysis between PO, and a truncated fragment lacking the N-terminal unique region of POIP, indicated that the N-terminal unique region is necessary for interaction between PO and POIP. The expression level of the POIP mRNA is increased by bacterial injection into T. molitor larvae. This suggests that POIP might be engaged in the humoral defense reaction.

• Korean Journal of Microbiology
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• v.28 no.3
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• pp.274-277
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• 1990

The hyphal tip phenoloxidases of Coprinus congregatus were localized by the protoplast-concanavalin A method. Protoplast were generated from cultures grown on a solid medium which was solidified with a new gelling agent, Pluronid Polyol F127, instead of agar. the enzymes were associated with the cell membrane which might work as a transducer in the light recepter complex.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.138-144
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• 2016

Phenoloxidase (PO) is an oxidizing enzyme and plays crucial roles in insect immunity and cuticle sclerotization. High oxidizing activity of chlorine dioxide gives effective control activities against microbes and insect pests. These allowed us to assess any inhibitory activity of chlorine dioxide against PO with respect to insect immunity. PO activities of the Indeanmeal moth, Plodia interpunctella, was detected in both hemocytes and plasma. Upon bacterial challenge, PO activity was significantly increased especially in plasma. However, the immune challenge coupled with chlorine dioxide treatment did not enhance PO activity. When different chlorine dioxide concentrations were incubated with activated PO by immune challenge, they did not inhibit the activated PO. These results indicate that chlorine dioxide suppresses PO activity by inhibiting PO activation.

• Journal of fish pathology
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• v.22 no.3
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• pp.293-303
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• 2009

Effects of stress on the low salinity stress were examined in the pacific abalone Haliotis discus discus. Changes in survival rate, hemolymph count, antioxidant enzyme activities (catalase: CAT and superoxide dismutase: SOD), respiratory burst activity, phenoloxidase activity, lysozyme activity and expression of heat shock protein 70 (HSP70) mRNA were measured 0, 3, 6, 12, 24 or 48hours after low salinity treatment with 25, 30, 33 and 35 psu. Survival rates of pacific abalone were 100% at 33 and 35 psu, but 93 and 97% at 25 and 30 psu for 48 hours, respectively. Hemolymph counts decreased in the time elapsed-dependent way at all of the experimental groups. At low salinity, 25 and 30 psu, SOD and CAT activity increased compared to the experimental group of 33 psu. Moreover, respiratory burst activities of the pacific abalone seemed to have no effect on low salinity stress at any experimental group. However, phenoloxidase activity is an important component of the defence against pathogen that was decreased in a reduction of salinity dependent way. Lysozyme activity also immediately reduced at 25 psu experimental group for 48 h. The HSP70 mRNA was weakly expressed at 33 psu, but strongly detectable at 25 psu experimental group. The HSP 70 mRNA expression in gill increased in the time elapsed-dependent way at 25 psu experimental group and then recovered at 48 h. These results suggest that low salinity stress give rise to inhibitory action of immune system as a result of the decrease of phenoloxidase and lysozyme activity in the pacific abalone, especially.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.157-167
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• 1987

The have been many reports that phenoloxidase are correlated with development in many fungi. C. congregatus, one of nushroom-forming basidiomycetes, which requires light for its development also has phenoloxidases. In C. congragatus, there are two sets of membrane-associated phenoloxidase (PHO I and PHO II) which are differentiated by their isozyme patterns, and each enzyme set consists of two different subtrate specific enzyme protein; o-tolidine reacting enzyme, and DOPA reacting enzyme. PHO I which is localized by a protoplast-concanavalin A technique by using a new solidifying agent, Pluronic Polyol F 127, instead of agar appears in the vegetative hyphae, and PHO II appears at the early primordial stage on agar and at the sclerotial stage of liquid shake cultures. Inhibition of PHO I with the enzyme inhibitors inhibits mushroom formation as well as melanization of the vegetative hyphae at concentrations which do not inhibit the vegetative growth. PHO I deficient mutants do not form mushrooms or melanins, and the mutants show abnormal nuclear migration patterns. PHO II has roles; possibly cementing the adjacent hyphae during the actual three dimensonal structure formation, and melanizing mushrooms and sclerotia. The possible roles of PHO I in the light reception complex and in melanin formation, the function of malanin, and possible roles of postulated post translational modifying enzymes which regulate the phenoloxidases, nuclear migration pattern, and self-nonself recognition mechanism are discussed.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.05a
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• pp.96-96
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• 2002

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.169.2-169
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• 1996

No Abstract, See Full Text