• Plant Resources
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• 제1권2호
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• pp.98-104
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• 1998

The effects of basal media, sucrose and phytohormone concentrations, and gelling agent combinations on in vitro frond proliferation of Lemna gibba G3 and 24 additional Lemna gibba strains were examined. Frond proliferation was equivalent on Schenk and Hidebrand. Murashige and Skoog. Nitsch and Nitsch, and Gamborg's B5 media and poor on murashige and Skoog medium in the absence of benzyladenine. With the addition of benzyladenine, Schenk and Hildebrand and Gamborg's B5 Were superior and equivalent. The addition of benzuyladenine increased equally frond proliferation at either 1 or $10{\mu}M$, however at $10{\mu}M$ fronds were severely curled or fused. Benzyladenine and thidiazuron suppressed root growth but kinetin was found to greatly enhance root growth. Gibberellic acid inhibited frond proliferation. Frond proliferation was significantly different on the four sucrose concentrations of 0, 1, 3, and 5% Among them, 3% sucrose was found to be superior. The reduced frond size observed in cultures grown on 8% sucrose could be explained by showing medium osmotic potential in excess of frond water potential. Gell agents also varied significantly in their ability to promote frond proliferation with 0.25% Gelrite or a mixture of 0.15% Gelrite and 0.4% agar. Proliferation of 25 Lemna gibba strains on medium neat optimal for Lemna gibba G3 showed a six-fold variation across strains with Lemna gobba G3 placing in the top 5 fastest proliferating strains.

• 한국수산과학회지
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• 제36권5호
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• pp.469-473
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• 2003

Transplantation of Sargassum horneri to natural substrate using the rope seeding method was undertaken. Seeding of S. horneri was grown on net in an indoor tank up to 0.2-0.3 cm in frond length for 2 months, and then transplanted to an architecture tile $(10\times10\;cm)$ with underwater glue and an iron pipe. After two months, number of S. horneri on the tile decreased because of grazing by herbivores. However, S. horneri on the iron pipe grew up to 0.5-2.0 cm in frond length. After 7 months, they rapidly grew up to a frond length of 11.0-203.0 cm with a mean frond length of 122.6 cm. S. horneri grew up to a maximum frond length of 313.0 cm, and mean frond length of 228.0 cm, after 10 months. The artificial S. hornevi beds can be used to clean the seawater and also be utilized as a source of marine biomass as well as for supplying habitat, shelter and spawning beds for fish and invertebrates.

• Applied Microscopy
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• 제41권1호
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• pp.55-60
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• 2011

부엽성 개구리밥은 엽상체, 연결사, 뿌리로 이루어진 축소된 수생식물로 엽상체는 특정한 시기에 물속에 가라앉는 휴면구조인 잠아를 형성한다. 식물세포의 분화발달에서 중요한 기능을 수행하는 색소체는 개구리밥의 거의 모든 기관에 분포하며, 특히 잠아 형성 및 수중 침강에 있어서 이들 색소체와의 연계성이 보고되어 있다. 본 연구에서는 개구리밥 식물체 내 모든 조직을 구성하는 각각의 세포들을 대상으로 색소체 특성에 초점을 두어 전자현미경으로 연구하였다. 생장 중의 엽상체는 활발한 분열로 개체를 계속 증식시키고, 특정 시기에 잠아원기를 형성하여 엽상체-잠아원기-잠아-엽상체원기-엽상체의 분화과정을 반복한다. 개구리밥 조직에 발달하는 색소체는 전색소체, 엽록체, 전분체로 크게 대별되며, 특히 색소체의 크기, 틸라코이드막계, 녹말입자 형성 등은 엽상체와 잠아 조직 간에 뚜렷한 차이를 보인다. 엽상체 및 잠아원기 엽육세포에는 비교적 작은 전색소체가 세포질에 분산되어 다수 분포하고, 기질 내에는 틸라코이드막계 및 녹말입자가 거의 형성되지 않는다. 반면, 생장 중의 엽상체에는 엽록체들이 중앙의 큰 액포를 따라 위치하고, 기질에는 그라나를 형성하는 틸라코이드막계가 발달한다. 유사한 형태의 엽록체가 근관에 발달하나 뿌리의 피층 및 연결사 색소체에는 녹말입자는 거의 나타나지 않는다. 잠아원기와는 대조적으로 잠아조직에는 매우 큰 전분체들이 축적된다. 이들 전분체는 기질에 내부 막의 분화 없이 당 축적에 의한 거대 녹말입자를 형성하여 무거운 구조가 된다. 이와 같이 엽상체, 연결사, 뿌리조직에 형성된 엽록체로 광합성을 수행하여 생장발달에 필요한 에너지를 생성 활용하는 반면, 잠아는 에너지 생성이나 활용이 아닌 휴면상태 유지에 필요한 독특한 구조로 각각 발달한다. 축소된 개구리밥 식물체 내 색소체 및 각각의 세포와 조직들은 최소한의 구조로 분화되나 기능은 고도로 분업화된 독특한 수생식물이라 할 수 있다.

• ALGAE
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• 제27권1호
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• pp.33-42
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• 2012

Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata) consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores ($31.2{\pm}13.7%$ vs. $19.4{\pm}7.3%$, mean ${\pm}$ standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density ($g\;m^{-2}$) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.

• ALGAE
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• 제22권2호
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• pp.107-116
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• 2007

Annual growth segments of Ascophyllum nodosum (L.) Le Jolis (Fucales, Fucaceae) are denoted by air bladders that form each spring. By examining annual growth segments, it may be possible to infer information about the physical conditions during the growth period; however, it is uncertain whether the annual segments will expand in size after the initial growth. We examined A. nodosum segments from three populations in Nova Scotia, and statistically evaluated whether the annual growth (length, mass, and maximum diameter) of segments was independent of the age of the frond, whether the segments increased in size after the initial growth, and whether the segment lengths were correlated with mean water temperatures and mean air temperatures when the segments were formed. We found that the growth in length of A. nodosum is dependent on the age of the frond, but frond age explained less than 12 % of the overall variation in length. However, the mass and maximum diameter of segments were independent of the age of the frond. Differences occurred between the lengths of segments formed in different years, but there was no significant correlation with regional mean water or air temperatures. This study indicates that the length of A. nodosum segments may be an indicator of the annual physical characteristics of a site, but future studies are needed to identify which factors have the strongest influence on growth patterns.

• 한국수산과학회지
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• 제53권5호
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• pp.665-671
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• 2020

The chemical and rheological properties of fucoidan and alginate prepared from different parts of Undaria pinnatifida (sporophyll, frond, stipe) were investigated. The algal materials were extracted with HCl (pH 2.0, 3 h at 70℃) to prepare fucoidan, and the remaining solid was continuously re-extracted with Na₂CO₃ (pH 10.0, 70℃, 3 h) to prepare alginic acid. The fucoidan and alginic acid contents in the sporophyll, frond, and stipe were 11.14%, 3.84%, and 1.73% and 22.04%, 37.14%, and 31.74%, respectively. The content of fucoidan and alginate depends on the part extracted. The fucoidan extracted from the sporophyll mainly consists of fucose and galactose, but the fucoidan extracted from frond and stipe contains mannose in addition to fucose and galactose. Fourier-transform infrared spectroscopy analysis of fucoidan and alginate suggests the presence of sulfate groups (1261 and 840 cm^-1) and carboxyl groups (1626 and 1419 cm^-1), respectively. Alginate solutions (5%) had a low viscosity of 10.84-31.63 mPa·s. The activation energies of fucoidan and sodium alginate were 14.45-18.38 kJ/mol and 18.61-22.06 kJ/mol, respectively. The D-mannuronic acid/L-guluronic acid (M/G) ratios of alginate showed a relatively high (frond, 3.72; stipe, 2.88; and sporophyll, 1.80).

• 한국수산과학회지
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• 제17권5호
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• pp.391-397
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• 1984

The seasonal and portional variation in the composition of uronic acid of alginic acid from Eckionia cava was investigated. The sample was collected from the coast of Ieechun Illkwangmyun, Yangsangun, Kyungnam, Korea, in the period of January to December in 1982. In seasonal variation of the content of alginic acid, the range of variation was larger in the frond than in the stipe, It was the highest content in between February to April, and the lowest in between August to October, and the content was more in the stipe than in the frond. The uronic acid ratio(M/G ratio) was varied seasonaly in a relationship with the variation of the alginic acid content. The maximum M/G ratio appeared in the period of December to March and minimum May to August, and the average values of the M/G ratios in the periods were 3.08, 2.64 in the frond and 2.91, 1.39 in the stipe, respectively. Additively a year mean values were 3.22 in the frond and 2.18 in the stipe.

• 한국수산과학회지
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• 제17권6호
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• pp.492-498
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• 1984

We have reported the seasonal and portional variation in the composition of uronic acid of alginic acid from Ecklonia cava in the previous study. In the present paper, uronic acid block structure of alginic acid from Ecklonia cave was investigated, and some related properties such as viscosity, the dependence on temperature and substitution of metallic ion were also discussed. The proportion M block was highest amnog three blocks in both of frond and stipe. The average values of M and G block ratios were $51.6|%\;and\;32.3\%$ in the frond, whereas $45.7\%\;and\;38.6\%$ in the stipe, respectively. The proportions of alternating blocks in the frond and stipe were similar, and the values were $16.1\%$ in the frond and $15.6\%$ in the stipe. The viscosity of $1\%$ sodium alginate solution was almost inversely proportional to the M/G and/or M block ratio. Viscosities were marked maximum from summer to autumn and minimum winter to spring. In the value of lower M/G and M block ratio, the viscosity seemed to have a considerable dependence on temperature. The temperature dependence was more appearant in the alginic acid from the frond (M/G ratio, 0.95; M block, $54.2\%$) collected in July and the stipe (M/G ratio, 1.61; M block $47.6\%$) in April. The affinity with metallic ion appeared higher in order of $Pb^{2+}>Cu^{2+}>Co^{2+}>Zn^{2+}$. The amounts of metallic ion exchange of the $Pb^{2+},\;Cu^{2+},\;Co^{2+}\;and\;Zn^{2+}$ were ranged from 3.4. to 4.7, 2.5 to 3.2, 1.8 to 2.2 and 1.6 to 1.7 meq/(g. sodium alginate), respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제14권8호
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• pp.1073-1077
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• 2001

Forty three 7-month old, Barbados Black $Belly{\times}Malin$ crossbred sheep were used for the trial. They were allotted into three treatment groups fed varying levels of oil palm (Elaeis guineensis) frond pellets and commercial sheep pellets. Treatment diets were 80% commercial pellet+20 % (% w/w) oil palm frond pellet (CON group, n=15), 50% commercial pellet+50% oil palm frond pellet (% w/w) (HAF group, n=14) and 80% oil palm frond pellet+20% (% w/w) commercial pellet (OPF group, n=14). The plasma fatty acid profiles from these animals were compared before and after 14 weeks of feeding. Results showed that total unsaturated fatty acid content in the CON group had increased by 10% (p<0.01) from the pre-treatment values. All three treatment groups had significantly different plasma n-6 and n-3 polyunsaturated fatty acid contents at the end of the trial. In fact, the CON group had significantly (p<0.01) more n-6 polyunsaturated fatty acid content compared to its own initial values, and also the values from the HAF and OPF groups. However there was a significant (p<0.01) decline in plasma n-3 polyunsaturated fatty acids in all groups. The final total unsaturated to saturated fatty acid content ratio was significantly (p<0.01) highest in the CON group, demonstrating the high plasma unsaturated fatty acid content in these animals. This study shows the plasma unsaturated fatty acids in sheep can be increased by dietary manipulation.

• Journal of Plant Biology
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• 제33권3호
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• pp.197-202
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• 1990

Exogenously applied spermine, spermidine and putrescine caused a delay of senescence in fronds Lemna gibba G3 under continuous illumination. When the proximal half of a frond containing the meristematic“pockets”was removed, endogenous spermidine level in the distal half (half frond) increased initially to a miximal level, which was followed by a decline during a period of 10 days of incubation in light. No appreciable changes were observed with putrescine or spermine levels. Treatment of fronds with $\alpha$-difluromethylarginine (DFMA) resulted in both reduced level of spermidine and enhancement of chlorophyll loss in half fronds. $\alpha$-difluoromethylornithine (DFMO) was found to be virtually ineffective in either parameter. Results of experiments with ABA and kinetin indicate that there is a close correlation between the progress of senescence and spermidine level in Lemna fronds under illumination. It is suggested that endogenous level of spermidine is associated, at least in part, with frond senescence in this aquatic plant.