• Journal of Aquaculture
• /
• v.13 no.4
• /
• pp.353-357
• /
• 2000

Porphyra pseudolinearis and P. dentata from Korea were crossed and the hybrid was cultured at different temperatures (5, 10, 15, 20 or $25^{\circ}C$), photon flux densities (10, 20, 40 or 80${\mu}$mol m$^{-2}$s$^{-1}$) under photoperiods (14L:10D and 10L:14D). In the hybrids, the conchocelis grew faster at 2$0^{\circ}C$ and 40$\mu$mol m$^{-2}$ s$^{-1}$ at $25^{\circ}C$ only, and were abundant, when cultured under 10L:14D. Foliose thalli of the hybrid grew rapidly at conditions of 10-2$0^{\circ}C$, 10L:14D and 15-2$0^{\circ}C$, 14L:10D but slowly at 5 and 2$0^{\circ}C$. No archeospores were observed any tested culture condition. Spermatangial and zygotosporangial sori were formed at the marginal portion o mature thallus. Zygotospores from the hybrid were released at 10-2$0^{\circ}C$ under both photoperiods, and gave rise to form conchocelis filament. Monoecious thalli were observed at 1$0^{\circ}C$ under 14L:10D. Neither monospores nor protothalli were produced from the conchocelis in culture.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.33 no.6
• /
• pp.496-500
• /
• 2000

Partial fragments of nuclear 185 rDNAs from morphologically wide and narrow thalli of the seaweed Porphyra pseudolineazis were amplified and sequenced to compare their DNA homology. Both sequences of 311 base pairs showed $100{\%}$ identical each other. They showed $97.7{\%}$ similarity with a wild strain collected at Sodol in Kangwondo, and $99.4{\%}$ similarity with the GenBank accession number AB013185 of the Japanese P. pseudolinearis. Thus the morphological difference of wide and narrow blades might not be a classification criterion for the sub-species level of P. pseudolinearis.

• Journal of Life Science
• /
• v.13 no.4
• /
• pp.516-521
• /
• 2003

Optimal conditions of protoplast isolation from the seaweed Prophyra pseudolinearis have been described. The P. pseudolinearis is one of indigenous and dominant Porphyra species in the East Sea region. Protoplasts have been released by enzymatic treatment of 2% agarase and 2% hemicellulase in 25mM MES buffer, pH 6.0 containing 0.5 M sorbitol. The protoplasts could be fused with neutral red-stained protoplasts of P. okamurae by the addition of polyethylene glycol 8000 solution.

• ALGAE
• /
• v.26 no.1
• /
• pp.79-86
• /
• 2011

Physiological studies on the hybrid by crossing between two dioecious species, Porphyra pseudolinearis and P. dentata from Korea were conducted at constant temperatures (5, 10, 15, 20, and $25^{\circ}C$), at photon flux densities (10, 20, 40, and $80\;{\mu}mol\;m^{-2}s^{-1}$) under photoperiods (14 L : 10 D and 10 L : 14 D). In the hybrid, higher growth of conchocelis was observed at 20 and $40\;{\mu}mol\;m^{-2}s^{-1}$ under 14 L : 10 D. Conchosporangial branches were produced under $10-80\;{\mu}mol\;m^{-2}s^{-1}$ at only $25^{\circ}C$, and were abundant when the conchocelis was cultured under 10 L : 14 D. Foliose thalli of the hybrid grew well at the conditions of $10-20^{\circ}C$, 10 L : 14 D and $15-20^{\circ}C$, 14 L : 10 D. The foliose thalli grew very slowly at $5^{\circ}C$ and $30^{\circ}C$, respectively. No archeospores were observed at any culture conditions. Spermatangial and zygotosporangial sori were formed at the marginal portion of mature thallus. Zygotospores from the hybrid were released at $10-2^{\circ}C$ under both photoperiods, and gave rise to form conchocelis filament. Monoecious thalli were observed at $10^{\circ}C$ under 14 L : 10 D. Neither monospores nor protothalli were produced from the conchocelis in culture.

• Journal of Aquaculture
• /
• v.7 no.1
• /
• pp.1-7
• /
• 1994

The effects of temperature and light intensity on the photosynthesis were investigated in fronds and cultivated filaments of Porphyra pseudolinearis Ueda. The optimum temperatures for total photosynthesis of fronds and filaments were $25\~30^{\circ}C\;and\;20^{\circ}C$, respectively. The photosynthetic rates of fronds and filaments based on light intensity were shown in a typical light saturation curve where the rates were constant over the light intensity of approximately 10,000 lux. The compensation points were 2,100 lux in fronds and 900 lux in filaments. The photosynthetic rate of filaments was 5 to 10 times greater than that of fronds. This would be very advantageous for filaments to conduct photosynthesis in the condition of dim light.

• Journal of Life Science
• /
• v.14 no.2
• /
• pp.331-338
• /
• 2004

Growth and sexual differentiation of the seaweed Porphyra pseudolinearis Ueda have been investigated monthly in the intertidal zone of the East Sea, Korea. Young blades of P. pseudolinearis appeared at the beginning of October. Carp os pores were released at the end of November immediately after carposporangia formation. Then the thalli of P. pseudolinearis were extinguished at the end of March. Young thalli were budded through the stages of conchocelis and conchospore. Thalli showed lanceolate type in shape, cordate type in holdfast, absence of microscopic spinulate process and sexual generation. Ratios of length to width in female thalli ranged from 5.6 to 7.4 at the maturation in December and slightly decreased 3.3 to 4.8 in January and 4.9 to 7.3 in December while the ratios of male thalli ranged from 4.2 to 4.8 in January. On October 12, average five individuals were obsered in a quadrate (30 cm ${\times}$ 30 cm), 238$\pm$18 individuals for the maturation stage in December and then it was reduced to 150 individuals in February and 15 individuals in March. Average sex ratios for female, male and vegetative thalli were 31.3% 46.9% and 21.9% respectively in early December, the beginning time of sex maturation. The sex ratio of female and male thalli in December 17, changed to 69.4%, 30.6% respectively.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 1998.06a
• /
• pp.151.1-152
• /
• 1998

• Journal of Life Science
• /
• v.13 no.3
• /
• pp.359-364
• /
• 2003

The seaweed Porphyra pseudolinearis as a dominant species grows at upper of the intertidal zone of the East Sea from October to March. Vegetative cells have not matured during October when observed with naked eye and microscope. In the middle of November, although it didn't distingush between female and male gametophytes by eye, it showed antheridium and carpogonium when observed vertical section under microscope. From early December, It could be distinguished female and male gametophytes clearly. From Feburary it showed shorted length of thalli by release of spermatangia and carposporangia as maturation. At early March, the colar has been decaeded and side of thalli has been melted, completed of release of spermatia. At the end of December, the average length and width of female thalli were 149.9$\pm$5.6mm and 22.2$\pm$2.3mm, respectively. The length and width of male thalli were 149.9$\pm$9.4mm and 20.7$\pm$1.8mm. At the end of January, the average length and width of female thalli were 94.6$\pm$6.4mm and 29.1mm$\pm$5.1, respcetively. The length and width of male thalli were 107.8$\pm$7.3mm and 25.9$\pm$0.9mm. From this period lengths of female and male thalli have already been shortned by the release of spermatia and carpogonia.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.6
• /
• pp.1166-1172
• /
• 1998

A method for the isolation and purification of DNA from a red algae, Porphyra was innovated. The innovation of the method consists mainly of three steps that include sodium acetate treatment, chloroform extraction, and 0.2 volume isopropanol precipitation step. The sodium acetate treatment was designed to remove polysaccharide contamination, and the isopropanol step to remove proteins and salts contaminents. Genomic DNA,s of several species(for example, P. tenera, P. yezoensis, P. seriata, and P. pseudolinearis) was successfully isolated by the innovated method. The amount of DNA purified from one g of sample material with the innovated method was 53 g in average. The resulting DNA was characterized to include high molecular weight and showed no nuclease activity. The DNA was pure enough to be digested directly by various restriction enzymes without any difficulties. Porphyra DNA was pure enough and adequate for amplification reaction through the polymerase chain reaction (small nuclear rDNA PCR amplification).

• ALGAE
• /
• v.18 no.4
• /
• pp.321-331
• /
• 2003

Cryopreservation of sporothalli of the red alga Porphyra (P. seriata, P. yezoensis, P. tenera, P. pseudolinearis and P. dentata) was performed by the two-step cooling method in liquid nitrogen. The algal samples were suspended in various cryoprotective solutions, and slowly cooled to -40$^{\circ}C$ in 4 hours using a programmed freezer. After the first slow cooling the suspensions with cryoprotectants were immediately immersed in liquid nitrogen. The suspension from the programmed freezer was thawed quickly by agitation of the vial in a water bath at 40°C. When ice in the suspension of cryogenic vial was mostly melted, the vial was transferred to an ice bath for complete melting of the residual ice. The cryoprotectants in the vial were washed off by gradual dilution with seawater. The viability of the cell was assessed with neutral red staining. The viability of Porphyra samples ranged 54.6-70.9% when the mixed suspension of 10% dimethylsulfoxide and 0.5 M sorbitol in 50% seawater used as a cryoprotectant.