RESUMO
To exploit insect-derived fungi, insects were collected from seven different regions in Korea, including Gyeongbuk, Goryeong, and several fungi were isolated from them. A fungal strain designated 21-64-D was isolated from riparian tiger beetle (Cicindela transbaicalica) and morphologically identified as a species belonging to the genus Oidiodendron. Phylogenetic analysis using the nucleotide sequences of internal transcribed spacer (ITS) regions and the partial sequence of the large subunit of the nuclear ribosomal RNA (LSU) gene revealed the distinct phylogenetic position of the isolate among recognized Oidiodendron species including its closest neighbors O. chlamydosporicum, O. citrinum, O. maius, and O. pilicola. The hyphal and conidial morphology of the strain, particularly club-shaped hyphae, clearly differentiated it from its close relatives. Results indicated that 21-64-D is a novel species in the genus Oidiodendron, for which the name Oidiodendron clavatum sp. nov. is proposed.
RESUMO
Polylactic acid (PLA) and polycaprolactone (PCL) are commercially available bioplastics that are exploited worldwide, and both are biodegradable. The PLA and PCL polymer-degrading activity of 30 fungal strains that were isolated from terrestrial environments were screened based on the formation of a clear zone around fungal colonies on agar plates containing emulsified PLA or PCL. Among them, five strains yielded positive results of biodegradation.Strains Korean Agricultural Culture Collection (KACC) 83034BP and KNUF-20-PPH03 exhibited PCL degradation; two other strains, KACC 83035BP and KNUF-20-PDG05, degraded PLA; and the fifth strain, KACC 83036BP, biodegraded both tested plastics. Based on phylogenetic analyses using various combinations of the sequences of internal transcribed spacer (ITS) regions, RPB2, LSU, CAL, and b-TUB genes, the above-mentioned strains were identified as Apiotrichum porosum, Penicillium samsonianum, Talaromyces pinophilus, Purpureocillium lilacinum, and Fusicolla acetilerea, respectively. Based on our knowledge, this is the first report on (i) plastic biodegraders among Apiotrichum and Fusicolla species, (ii) the capability of T. pinophilus to degrade biodegradable plastics, (iii) the biodegradative activity of P. samsonianumagainst PCL, and (iv) the accurate identification of P. lilacinum as a PLA biodegrader. Further studies should be conducted to determine how the fungal species can be utilized in Korea.
RESUMO
Polylactic acid (PLA) and polycaprolactone (PCL) are commercially available bioplastics that are exploited worldwide, and both are biodegradable. The PLA and PCL polymer-degrading activity of 30 fungal strains that were isolated from terrestrial environments were screened based on the formation of a clear zone around fungal colonies on agar plates containing emulsified PLA or PCL. Among them, five strains yielded positive results of biodegradation.Strains Korean Agricultural Culture Collection (KACC) 83034BP and KNUF-20-PPH03 exhibited PCL degradation; two other strains, KACC 83035BP and KNUF-20-PDG05, degraded PLA; and the fifth strain, KACC 83036BP, biodegraded both tested plastics. Based on phylogenetic analyses using various combinations of the sequences of internal transcribed spacer (ITS) regions, RPB2, LSU, CAL, and b-TUB genes, the above-mentioned strains were identified as Apiotrichum porosum, Penicillium samsonianum, Talaromyces pinophilus, Purpureocillium lilacinum, and Fusicolla acetilerea, respectively. Based on our knowledge, this is the first report on (i) plastic biodegraders among Apiotrichum and Fusicolla species, (ii) the capability of T. pinophilus to degrade biodegradable plastics, (iii) the biodegradative activity of P. samsonianumagainst PCL, and (iv) the accurate identification of P. lilacinum as a PLA biodegrader. Further studies should be conducted to determine how the fungal species can be utilized in Korea.