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Bacterial nanocellulose (BNC) is characterized by high purity and excellent mechanical properties; however, its production is constrained by low yield. Therefore, efforts aimed at improving its yield and material properties are imperative. This study investigated the effect of adding different concentrations (0%, 0.5%, and 1.0%) of cellulose nanocrystal (CNC) in Hestrin–Schramm modified medium on the yield and properties of BNC produced by Komagataeibacter sp. SFCB22-18. The BNC yield increased as following an increase in added CNC concentration. Also, the morphology, structure, crystallinity, thermal stability, and mechanical properties of BNC improved after CNC incorporation. A low CNC concentration (0.1%) favored mechanical strength, whereas 0.5% gave the optimum morphology, structural, and thermal stability. These results showed that modifying BNC with CNC could help increase yield and improve its properties, and thus; the potentiality of BNC in various applications would be much enhanced.

Interaction between fungi and insects such as ants, beetles, wasps and termites inhabiting dead pine trees has significant ecological implication in the forest as they can decompose wood debris and add nutrients to the soil; however, only scarce information is available regarding the interaction between wood-decaying fungi and ants. We investigated wood-decaying fungi co-occurring with ants in dead pine trees of South Korea. A total of 57 pairs of wood-decaying fungi and ants were collected from 11 localities. 30 species of wood-decaying fungi and 14 species of ants were identified based on morphology and molecular analysis. Fungal species belonging to Trichaptum, Xylodon, Hyphodontia, and Ceriporia were dominant and co-occurred with common ant species of Lasius, Camponotus, Pristomyrmex, and Crematogaster across most of the sampling sites. This study provides a new baseline in unravelling the complex interaction between wood-decaying fungi and ants in forest ecosystems.

The aggregation of decaying egg masses of sailfin sandfish along the mid-east coast of Korea is a major environmental problem with concurrent negative economic consequences. In an effort to ameliorate decaying egg masses, we investigated the diversity and community structure of fungi from egg masses and tested for their cellulase and protease activity. A total of 1108 strains were identified based on morphology and multigene analyses, and found to represent 184 fungal species. Paradendryphiella salina was the most dominant species, followed by Penicillium crustosum and Penicillium aurantioviolaceum. The fungal community displayed a significant degree of variation relative to both egg mass color and locality. Over 50% of species detected in this study exhibited both cellulase and protease activity. This study suggests that fungi play an important role in nutrient recycling at intertidal zones and thus may have potential industrial applications that can help resolve the environmental problems associated with egg mass aggregation.

For the seasonal changes of fungi (Ascomycota and Basidiomycota) diversity, we performed a biweekly survey of macrofungi on defined plot in a Korean red pine (Pinus densiflora) stand (Gwangneung Forest, Pochen-si, Korea) from April 2014 to December 2014. The plot was surveyed 18 times. We also investigated the diversity of the soil fungi community during four seasons using pyrosequencing method. The collected macrofungi (25 specimens) were classified into one phylum, one class, four orders, 10 families, 13 genera, and 17 species; the soil fungal communities were classified into two phyla, 15 classes, 43 orders, 91 families, and 124 genera (49,937 sequence reads), designated as 124 genus-level operational taxonomic units. Using macrofungal collection data, environmental factor data (n = 10), and pyrosequencing data, we evaluated changes in fungal diversity with seasons and soil layers. Nonmetric multidimensional scaling ordination revealed distinct clusters of genus-level operational taxonomic units assemblage with season. Two environmental factors (exchangeable K and C/N ratio) were found to be significantly associated with soil fungi communities in the Korean red pine stand. This study will lead to a better understanding of relationships between Korean red pine stand stands and soil fungal communities. Keywords: diversity, environmental factors, macrofungi, pyrosequencing, soil layers

Ips sexdentatus (six-spined engraver beetle) from Austria and Poland were dissected and examined for the presence of pathogens. Specimens collected in Austria were found to contain the ascomycetous fungus Metschnikowia cf. typographi. Infection rates ranged from 3.6% to 26.8% at different collection sites. M. cf. typographi infected midguts were investigated by histological, ultrastructural and molecular techniques. Extraordinary ultrastructural details are shown, such as ascospores with bilateral flattened flanks resembling alar rims at both sides of their attenuating tube-like ends. These have not yet been described in other yeast species. Molecular investigations showed a close phylogenetic relationship to the fungi Metschnikowia agaves and Candida wancherniae. Presence of the entomopathogenic fungus Beauveria bassiana found in Austria was confirmed both morphologically and molecularly. The eugregarine Gregarina typographi was diagnosed most frequently. Infection rates of all I. sexdentatus specimens ranged from 21.4% to 71.9% in Austria and 54.1% to 68.8% in Poland. Other entomopathogenic protists, bacteria, or viruses were not detected.

The veiled polypore, Cryptoporus volvatus, is distributed widely in North America and East Asia and is believed to have a mutualistic relationship with coleopteran species—the fungus providing food and shelter in basidiocarps and beetle helping disperse spores. Seventy fresh basidiocarps of C. volvatus were collected from the Japanese red pine (Pinus densiflora) in the spring season of 2013 from two sites in Korea. A total of 251 insects (101 adult and 150 larvae) were collected from the inside of basidiocarps and identified using morphology and mitochondrial cytochrome c oxidase subunit I (COI) sequences. Six species belonging to five coleopteran families were identified. The number of spores attached to the bodies of adult insects was counted and average spore counts for each of the six species ranged between 1.0 × 104 and 5.2 × 105 spores/individual. Across localities, three species were shared (Aethina suturalis, Trogossita japonica and Parabolitophagus felix) and carried spores at high densities on their bodies, making them more likely to aid in spore dispersal.

Radiata pine ( Pinus radiata ) lumber from Australia, Chile, and New Zealand is imported into Korea where it represents one of the most important sources of timber. Blue stain of this timber is a serious problem for which an integrated control strategy is being developed. One of the fungi that has been isolated from stained radiata pine sapwood in Korea is a Leptographium sp. that has a distinct Sporothrix synanamorph. The aim of this study was to classify this fungus. Morphological comparisons showed that this fungus is distinct from all other species of Leptographium and especially L. elegans and L. francke-grosmanniae that also have Sporothrix synanamorphs. Comparisons of sequence data for the ITS2 and part of the 28S rDNA genes as well as the β-tubulin gene also confirmed that this fungus represents an undescribed taxon, described here as Leptographium bistatum sp. nov.