• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.144-150
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• 2010

This study was aimed to screen bacteria of high alginate-degrading activity, to select the nitrogen source and concentration of NaCl and sodium alginate for the production of alginate-degrading enzyme, and to determine reaction conditions of enzyme. A novel alginate-degrading bacterium was isolated from abalone (Haliotis discus hannai) and named Methylobacterium sp. HJM27 by 16S rDNA sequence analysis. The optimum culture conditions for the production of alginate-degrading enzyme were 1.0% sodium alginate, 0.5% peptone, 0.3% yeast extract, 1.5% NaCl, $25^{\circ}C$ and 48 hours incubation time. The raw enzyme showed the highest activity at $25^{\circ}C$ and pH 9, and produced 1.217 g - reducing sugar per liter in 0.8% (w/v) sodium alginate for 30 minutes. Methylobacterium sp. HJM27 and its alginate-degrading enzyme would be useful for the production of bioenergy and biofunctional oligosaccharides from seaweed.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.243-249
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• 2012

This study was conducted to screen an alginate-degrading microorganism and to investigate the characteristics of the alginate-degrading activity of its crude enzyme. A marine bacterium which produces extracellular alginate-degrading enzymes was isolated from the brown alga Sargassum thunbergii. 16S rRNA sequence analysis and physiological profiling resulted in the bacterium's identification as a Vibrio crassostreae strain, named Vibrio crassostreae PKA 1002. Its optimal culture conditions for growth were pH 9, 2% NaCl, $30^{\circ}C$ and a 24 hr incubation time. The optimal conditions for the alginate degrading ability of the crude enzyme produced by V. crassostreae PKA 1002 were pH 9, $30^{\circ}C$, a 48 hr incubation time and 8% alginic acid. The alginate degrading crude enzyme produced 3.035 g of reducing sugar per liter in 4% (w/v) alginate over 1 hr.

• Journal of Microbiology and Biotechnology
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• v.30 no.1
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• pp.79-84
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• 2020

This study investigated the characterization and functionality of Undaria pinnatifida root (UPT) extracts, degraded using a crude enzyme from Shewanella oneidensis PKA1008. To obtain the optimum degrading conditions, the UPT was mixed with alginate degrading enzymes from S. oneidensis PKA 1008 and was incubated at 30℃ for 0, 3, 6, 12, 24, and 48 h. The alginate degrading ability of these enzymes was then evaluated by measuring the reducing sugar, viscosity, pH and chromaticity. Enzymatic extract at 24 h revealed the highest alginate degrading ability and the lowest pH value. As the incubation time increased, the lightness (L ^⁎) also decreased and was measured at its lowest value, 39.84, at 12 hours. The redness and yellowness increased gradually to 10.27 at 6 h and to 63.95 at 3 h, respectively. Moreover, the alginate oligosaccharides exhibited significant anti-inflammatory activity. These results indicate that a crude enzyme from S. oneidensis PKA 1008 can be used to enhance the polysaccharide degradation of UPT and the alginate oligosaccharides may also enhance the anti-inflammatory effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.109-114
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• 2006

For the purpose of oligosaccharide production from alginate, the main component in cell walls of brown algae, the alginate degrading bacteria have been screened from the seaweeds and soil. Among the isolated 69 strains, one strain showing the highest degrading activity was selected and identified as Bacillus licheniformis strain. The adequate sodium alginate concentration for growing the Bacillus licheniformis was $2.0\%$. The effective nitrogen source is nutrient broth $(0.1\%)$, and optimum initial pH, NaCl concentration, temperature and incubation time to produce the alginate degrading enzyme were 7.5, $2\%,\;30{\pm}2^{\circ}C$, and 144 hrs, respectively.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.372-378
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• 2013

An alginate-degrading bacterium, identified as Shewanella oneidensis PKA 1008 by 16S ribosomal RNA sequence analysis, was isolated from the green alga Ulva pertusa. Optimal conditions for the alginate-degrading ability of its crude enzyme were then determined. The optimal culture conditions for the growth of S. oneidensis PKA 1008 were pH 9, 2% NaCl, $30^{\circ}C$, and 24 hours incubation time. The crude enzyme produced by S. oneidensis PKA 1008 showed the highest alginate-degrading activity at pH 9, $30^{\circ}C$ and produced 1.001 g of reducing sugar per liter in 3.5% (w/v) sodium alginate for 1 hour.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.234-239
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• 1993

The alginate degrading bacteria have been screened from the marine environment. Sodium alginate and NaCl were required for cell growth and enzyme production of 145-C strain and the adequate concentrations were 0.7 and 2.5%, respectively. The effective nitrogen source was peptone and adequate temperature was 28$\pm$2$^{\circ}C$. The 145-C strain was identified as Vibrio sp. from biochemical and biological experiment. The extracellular enzyme produced by Vibrio sp. was purified and the molecular weight was estimated to be 27, 000.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.6
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• pp.888-897
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• 2015

The anti-inflammatory effect of alginate oligosaccharides on LPS-induced RAW 264.7 cells was investigated at different time points (0-60 h). The alginate oligosaccharides were produced by an alginate-degrading enzyme from Shewanella oneidensis PKA1008. The alginate oligosaccharides decreased the production of nitric oxide and proinflammatory cytokines [tumor necrosis factor-${\alpha}$, interleukin (IL)-$1{\beta}$, and IL-6] in a dose-dependent manner. The alginate oligosaccharides showed peak anti-inflammatory activity after 36 h of incubation; at that time point, reduced protein expression of NF-${\kappa}B$ p65, iNOS, and COX-2 was detected. Furthermore, the alginate oligosaccharide treatment reduced the formation of ear edema at 36 h compared to samples examined at 0 h when the oligosaccharides were administered at 50 and 250 mg/kg body weight, as well as dermal thickness and mast cell numbers in a histological analysis. These results suggest that alginate oligosaccharides are a promising anti-inflammatory agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.434-440
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• 2013

This study was conducted to screen the characteristics and alginate-degrading activity of marine bacterium isolated from brown seaweed (Sargassum thunbergii). The results of 16S ribosomal RNA sequence analysis the strain the genus Vibrio and the strain was subsequently named Vibrio sp. PKA 1003. The optimum culture conditions for the growth of Vibrio sp. PKA 1003 were at pH 7, 3% NaCl, $25^{\circ}C$, and 6% alginic acid, with a 48-hour incubation time. A crude enzyme preparation from Vibrio sp. PKA 1003, showed its highest levels of alginate-degradation activity when cultured at pH 9, $30^{\circ}C$, and 6% alginic acid, with a 63-hour incubation time. Thin layer chromatography analyses confirmed that the crude enzyme released monomers or oligomers from sodium alginate, and results from trypsin treatment showed that the alginate degrading activity depends on this enzyme produced by Vibrio sp. PKA 1003. These results suggest that Vibrio sp. PKA 1003 and its alginate-degrading crude enzyme is useful for the production of alginate oligosaccharides.

• Journal of Microbiology
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• v.44 no.3
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• pp.354-359
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• 2006

This study examined the capacity of immobilized bacteria to degrade petroleum hydrocarbons. A mixture of hydrocarbon-degrading bacterial strains was immobilized in alginate and incubated in crude oil-contaminated artificial seawater (ASW). Analysis of hydrocarbon residues following a 30-day incubation period demonstrated that the biodegradation capacity of the microorganisms was not compromised by the immobilization. Removal of n-alkanes was similar in immobilized cells and control cells. To test reusability, the immobilized bacteria were incubated for sequential increments of 30 days. No decline in biodegradation capacity of the immobilized consortium of bacterial cells was noted over its repeated use. We conclude that immobilized hydrocarbon-degrading bacteria represent a promising application in the bioremediation of hydrocarbon-contaminated areas.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.463-464
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• 2018

Tamlana sp. UJ94 isolated from seawater can degrade alginate. To identify the genomic basis of this activity, the genome was sequenced. The genome was composed of 4,116,543 bp, 3,609 coding sequences, and 35.2 mol% G + C content. A BLASTp search predicted the presence of 9 alginate lyases as well as 6 agarases, 5 amylases, 4 carrageenases, 1 cellulase, 4 pectate lyases, and 7 xylanases, indicating its ability to degrade diverse polysaccharides. The genome of strain UJ94 is a source of polysaccharide-degrading enzymes for bioconversion processes.