• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1245-1253
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• 2014

One-step sulfuric acid saccharification of the red alga Pterocladiella capillacea was optimized, and various detoxification methods (neutralization, overliming, and electrodialysis) of the acid hydrolysate were evaluated for fermentation with the thermotolerant yeast Kluyveromyces marxianus. A proximate composition analysis indicated that P. capillacea was rich in carbohydrates. A significant galactose recovery of $81.1{\pm}5%$ was also achieved under the conditions of a 12% (w/v) biomass load, 5% (v/v) sulfuric acid, $121^{\circ}C$, and hydrolysis for 30 min. Among the various detoxification methods, electrodialysis was identified as the most suitable for fermentable sugar recovery and organic acid removal (100% reduction of formic and levulinic acids), even though it failed to reduce the amount of the inhibitor 5-HMF. As a result, K. marxianus fermentation with the electrodialyzed acid hydrolysate of P. capillacea resulted in the best ethanol levels and fermentation efficiency.

• ALGAE
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• v.36 no.4
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• pp.327-332
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• 2021

Raw material of gelidioid red algae yielding high-quality agar has been in short supply due to overharvesting, but in situ farming of gelidioids has not been practical due to their slow growth. To produce vegetative seedstock of a cosmopolitan species, Pterocladiella capillacea, we investigated the number and length of regenerated branches arising from sectioned fragments during 3 weeks of laboratory culture at 10, 15, 20, and 25℃. All sectioned fragments formed axis-like branches mostly from the upper cut edge and stolon-like branches mostly from the lower cut edge, showing a high capacity of regeneration and intrinsic bipolarity. At 20℃, the number of regenerated branches increased to 2.74 ± 1.29 on the upper cut edge and 4.26 ± 2.66 on the lower cut edge. Our study reveals that the use of fragments bearing regenerated branches as seedstock can be a simple method to initiate fast propagation for mass cultivation in the sea or outdoor tank.

• ALGAE
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• v.25 no.1
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• pp.1-9
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• 2010

Although Pterocladiella is a well-known agar-producing red algal genus, its taxonomy in Korea appears to be confused. In the present study, we demonstrate the occurrence of Pterocladiella nana and P. tenuis, as well as P. capillacea in Korea on the basis of morphological and plastid rbcL sequence comparisons. P. capillacea commonly occurs along the coasts of Korea and has regular pinnate branches with abundant second-order branches, growing up to 10 cm in length. P. nana occurs in the intertidal zone of Jeju and is distinguished by the small size of its thalli (up to 5 cm) and regular branches with up to third-order branches. P. tenuis is distributed mostly subtidally on the southern coast of Jeju and has irregular branches with rarely second-order branches, growing up to 19 cm in length. We determined rbcL sequences from 19 specimens (15 from Korea and four from France) and downloaded 28 sequences from GenBank. Analyses of all 47 rbcL sequences revealed that each of three species was consistently resolved. P. capillacea and P. tenuis always formed a sister clade with P. nana at the base. Given that 12 rbcL haplotypes from 28 specimens of P. capillacea have been found to date, analysis of a fast-evolving gene from across the range of the species should highlight its genetic diversity.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1299-1306
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• 2014

Background: Nano-biotechnology is recognized as offering revolutionary changes in various fields of medicine. Biologically synthesized silver nanoparticles have a wide range of applications. Materials and Methods: Silver nanoparticles (AgNPs) were biosynthesized with an aqueous extract of Pterocladiella (Pterocladia) capillacea, used as a reducing and stabilizing agent, and characterized using UV-VIS spectroscopy, Fourier Transform Infra red (FT-IR) spectroscopy, transmission electron microscopy (TEM) and energy dispersive analysis (EDX). The biosynthesized AgNPs were tested for cytotoxic activity in a human hepatocellular carcinoma ($HepG_2$) cell line cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, 1% antibiotic and antimycotic solution and 2 mM glutamine. Bacterial susceptibility to AgNPs was assessed with Staphylococcus aureus, Bacillus subtilis [Gram+ve] and Pseudomonas aeruginosa and Escherichia coli [Gram-ve]. The agar well diffusion technique was adopted to evaluate the bactericidal activity of the biosynthesized AgNPs using Ampicillin and Gentamicin as gram+ve and gram-ve antibacterial standard drugs, respectively. Results: The biosynthesized AgNPs were $11.4{\pm}3.52$ nm in diameter. FT-IR analysis showed that carbonyl groups from the amino acid residues and proteins could assist in formation and stabilization of AgNPs. The AgNPs showed potent cytotoxic activity against the human hepatocellular carcinoma ($HepG_2$) cell line at higher concentrations. The results also showed that the biosynthesized AgNPs inhibited the entire panel of tested bacteria with a marked specificity towards Bacillus subtillus. Conclusions: Cytotoxic activity of the biosynthesized AgNPs may be due to the presence of alkaloids present in the algal extract. Our AgNPs appear more bactericidal against gram-positive bacteria (B. subtillus).

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.383-389
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• 2021

The Erythropeltidales are a common group of small, mostly epiphytic, marine red algae. However, they are little known in Korea. Many of the described species of Erythropeltidales differ subtly in morphology, and often the morphological differences are due to the substrate or environmental changes. Integration of molecular data with standardized culture conditions has been recommended to account for these algae. A Madagascaria species was first collected from the western coast of Korea and was identified as Madagascaria erythrocladioides based on the morphological and molecular characteristics. Morphological characteristics conformed well with its original description, and the phylogenetic analysis based on rbcL sequence showed Korean M. erythrocladioides nests in the same clade with the original species described in Japan with a genetic distance of 0.0-0.1%. This species was isolated from a red alga, Pterocladiella capillacea, in laboratory culture. The thallus ontogeny and host preference were examined by a co-culture with 13 different species of algae. Results showed a relatively broad host preference in mono-spore attachment and epiphyte development of Madagascaria erythrocladioides. Mono-spores of M. erythrocladioides attached to most of the red algal hosts' surfaces but no crustose thalli developed on some of the algal hosts even after one month of co-culture.