• Mycobiology
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• v.51 no.4
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• pp.239-245
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• 2023

Xylanase has been applied in various sectors, such as biomass conversion, paper, pulp, textiles, and pharmaceutical industries. This study aimed to isolate and screen potential xylanase-producing fungi from the soil of Suphan Buri Province, Thailand. Fifteen fungi were isolated, and their xylanase activities were tested by the qualitative method. The result showed that isolate SP3, SP10 and SP15 gave high xylanase activity with potency index (PI) of 2.32, 2.01 and 1.82, respectively. These fungi were selected for the xylanase quantitative test, isolate SP10 performed the highest xylanase activity with 0.535 U/mL. Through molecular methods using the 𝛽-tubulin gene, isolate SP10 was identified as Penicillium menonorum. The xylanase characteristics from P. menonorum SP10 were determined, including the xylanase isoforms and the optimum pH and temperature. The xylanase isoforms on SDS-PAGE indicated that P. menonorum SP10 produced two xylanases (45 and 54 kDa). Moreover, its xylanase worked optimally at pH 6 and 55 ℃ while reaching 61% activity at 65 ℃. These results proposed P. menonorum SP10 as a good candidate for industrial uses, especially in poultry feed and pulp industries, to improve yield and economic efficiency under slightly acidic and high-temperature conditions.

• Mycobiology
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• v.43 no.1
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• pp.49-56
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• 2015

The present study is the first report on the isolation of Penicillium menonorum from rhizosphere soil in Korea and its identification based on morphological characteristics and internal transcribed spacer gene sequence. The fungal isolate was named KNU-3 and was found to exhibit plant growth-promoting (PGP) activity through indole acetic acid (IAA) and siderophore production, as well as P solubilization. KNU-3 produced 9.7 mg/L IAA and solubilized 408 mg of $Ca_3PO_4/L$, and inoculation with the isolate significantly (p < 0.05) increased the dry biomass of cucumber roots (57%) and shoots (52%). Chlorophyll, starch, protein, and P contents were increased by 16%, 45%, 22%, and 14%, respectively, compared to plants grown in uninoculated soil. The fungus also increased soil dehydrogenase (30%) and acid phosphatase (19%) activities. These results demonstrate that the isolate KNU-3 has potential PGP attributes, and therefore it can be considered as a new fungus to enhance soil fertility and promote plant growth. Moreover, the discovery of PGP ability and traits of this fungus will open new aspects of research and investigations. In this study, plant growth promotion by P. menonorum KNU-3 is reported for the first time in Korea after its original description.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.175-185
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• 2020

Penicillium in section Exilicaulis is characterized by non-vesiculate monoverticillate and biverticillate stipes. Species in sect. Exilicaulis are commonly found in soil and plants in terrestrial environments; however, only a few species have been reported in Korea. To investigate the diversity of Penicillium sect. Exilicaulis, Penicillium species were isolated from terrestrial and marine environments. Based on sequence analyses of β-tubulin, calmodulin, and the second largest subunit of RNA polymerase II loci, 19 strains of Penicillium in sect. Exilicaulis were identified as P. citreonigrum, P. citreosulfuratum, P. corylophilum, P. menonorum, P. rubefaciens, P. velutinum, Penicillium sp. 1, and Penicillium sp. 2. Two of them, P. citreonigrum and P. citreosulfuratum, were confirmed to be new to Korea. Molecular phylogenies and detailed descriptions of the two unrecorded species are provided.