• The Korean Journal of Mycology
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• v.32 no.2
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• pp.89-94
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• 2004

This study was carried out to investigate the suitability of various agricultural by-products as basal substrates for the mycelial growth and fruiting body formation of Hericium erinaceum. For this aim, oak sawdust, cotton waste, sugarcane bagasse, Job's tears, rice hull, Chinese cabbage, and coconut waste were used as sole or mixed substrate(s). Corn waste and rice bran were used as nutrient supplements. The growth and density of mycelium, yield of fruiting body, and biological efficiency were compared among tested substrates colonized by Hericium erinaceum. The best measurement of mycelial growth and density, yield of fruiting body, and biological efficiency in a laboratory test was found in a spawn substrate composed with oak sawdust 80% and rice bran 20%. The suitability of this spawn substrate composition for Hericium fruiting body production was testified through practical tests in plastic bottles (850 ml) in a mushroom farm which had bottle cultivation facility. However, test in a mushroom farm which had plastic bag cultivation facility, best production of Hericium fruiting body (520 g per one bag) was observed in a spawn substrate composed of cotton waste 40%, saw dust 40%, corn waste 10%, and rice bran 10%.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.179-188
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• 2017

White-rot basidiomycetes are the organisms that decompose lignin most efficiently, and Trametes villosa is a promising species for ligninolytic enzyme production. There are several publications on T. villosa applications for lignin degradation regarding the expression and secretion of laccase and manganese peroxidase (MnP) but no reports on the identification and characterization of lignin peroxidase (LiP), a relevant enzyme for the efficient breakdown of lignin. The object of this study was to identify and partially characterize, for the first time, gDNA, mRNA, and the corresponding lignin peroxidase (TvLiP) protein from T. villosa strain CCMB561 from the Brazilian semiarid region. The presence of ligninolytic enzymes produced by this strain grown in inducer media was qualitatively and quantitatively analyzed by spectrophotometry, qPCR, and dye fading using Remazol Brilliant Blue R. The spectrophotometric analysis showed that LiP activity was higher than that of MnP. The greatest LiP expression as measured by qPCR occurred on the $7^{th}$ day, and the ABSA medium (agar, sugarcane bagasse, and ammonium sulfate) was the best that favored LiP expression. The amplification of the TvLiP gene median region covering approximately 50% of the T. versicolor LPGIV gene (87% identity); the presence of Trp199, Leu115, Asp193, Trp199, and Ala203 in the translated amplicon of the T. villosa mRNA; and the close phylogenetic relationship between TvLiP and T. versicolor LiP all indicate that the target enzyme is a lignin peroxidase. Therefore, T. villosa CCMB561 has great potential for use as a LiP, MnP, and Lac producer for industrial applications.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1255-1261
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• 2006

An alkaliphilic bacterium, Bacillus sp. strain BK, was found to produce extracellular cellulase-free xylanolytic enzymes with xylan-binding activity. Since the pellet-bound xylanase is eluted with 2% TEA from the pellet of the culture, they contain a xylan-binding region that is stronger than the xylan-binding xylanase of the extracellular enzyme. The xylanases had a different molecular weight and xylan-binding ability. The enzyme activity of xylanase in the extracellular fraction was 6 times higher than in the pellet-bound enzyme. Among the enzymes, xylanase had the highest enzyme activity. When Bacillus sp. strain BK was grown in pH 10.5 alkaline medium containing xylan as the sole carbon source, the bacterium produced xylanase, arabinofuranosidase, acetyl esterase, and $\beta$-xylosidase with specific activities of 1.23, 0.11, 0.06, and 0.04 unit per mg of protein, respectively. However, there was no cellulase activity detected in the crude enzyme preparation. The hydrolysis of agricultural residues and kraft pulps by the xylanolytic enzymes was examined at 50$^{\circ}C$ and pH 7.0. The rate of xylan hydrolysis in com hull was higher than those of sugarcane bagasse, rice straw, com cop, rice husk, and rice bran. In contrast, the rate of xylan hydrolysis in sugarcane pulp was 2.01 and 3.52 times higher than those of eucalyptus and pine pulp, respectively. In conclusion, this enzyme can be used to hydrolyze xylan in agricultural residues and kraft pulps to breach and regenerate paper from recycled environmental resources.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1218-1223
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• 2012

${\varepsilon}$-Poly-$_L$-lysine (${\varepsilon}$-PL), produced by Streptomyces or Kitasatospora strains, is a homo-poly-amino acid of $_L$-lysine, which is used as a safe food preservative. The present study investigates the combined use of cell immobilization and in situ adsorption (ISA) to produce ${\varepsilon}$-PL in shaken flasks. Loofah sponge-immobilized Streptomyces ahygroscopicus GIM8 produced slightly more ${\varepsilon}$-PL than those immobilized on synthetic sponge, and sugarcane bagasse. Moreover, loofah sponge supported the maximum biomass. Hence, loofah sponge was chosen for cell immobilization. Meanwhile, the ion-exchange resin D152 was employed for ISA. The loofah sponge-immobilized cells produced $0.54{\pm}0.1g/l$ ${\varepsilon}$-PL, which significantly increased to $3.64{\pm}0.32g/l$ after combining with ISA through the addition of resin bags. The free cells with ISA using the dispersed resin yielded $2.73{\pm}0.26g/l$ of ${\varepsilon}$-PL, an increase from $0.82{\pm}0.08g/l$. These data illustrate that the proposed combination method improved production most significantly compared with either immobilization or ISA only. Moreover, the immobilized cells could be repeatedly used and an ${\varepsilon}$-PL total amount of $8.05{\pm}0.84g/l$ was obtained. The proposed combination method offers promising perspectives for ${\varepsilon}$-PL production.