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The Xylariaceae and its relatives rank as one of the best-known members of the Ascomycota. They are now well recognized for their diversity, global distribution, ecological activities and their outstanding novel metabolites with wide ranging bioactivity., (© 2023. Crown.)

Xylaria species associated with termite nests or soil have been considered rare species in nature and the few which have been reported upon have been found to act as a rich source of bioactive metabolites. This study evaluated 10 ethyl acetate extracts of five new Xylaria species associated with termite nests or soil for their antioxidant activity, and cytotoxicity against different cancer and normal cell lines. DPPH and ABTS radical scavenging activities of the extracts demonstrated strong capacity with low IC 50 values. The highest observed activities belonged to X. vinacea SWUF18-2.3 having IC 50 values of 0.194 ± 0.031 mg/mL for DPPH assay and 0.020 ± 0.004 mg/mL for ABTS assay. Total phenolic content ranged from 0.826 ± 0.123 to 3.629 ± 0.381 g GAE/g crude extract which correlated with antioxidant activities. The high total phenolic content could contribute to the high antioxidant activities. Cytotoxicity was recorded against A549, HepG2, HeLa and PNT2 and resulted in broad spectrum to specific activity depending on the cell lines. The highest activities were observed with X. subintraflava SWUF16-11.1 which resulted in 11.15 ± 0.32 to 13.17 ± 2.37% cell viability at a concentration of 100 µg/mL. Moreover, LC-MS fingerprints indicated over 61 peaks from all isolates. There were 18 identified and 43 unidentified compounds compared to mass databases. The identified compounds were from various groups of diterpenoids, diterpenes, cytochalasin, flavones, flavonoids, polyphenols, steroids and derivatives, triterpenoids and tropones. These results indicate that Xylaria spp. has abundant secondary metabolites that could be further explored for their therapeutic properties.

The diversity of Xylaria species associated with termite nests in northeast Thailand was investigated. Among the 14 taxa included in this study, 11 species and one variety were described as new, and another two species resemble the existing taxa, X. escharoidea and X. nigripes . The newly described taxa are X. chaiyaphumensis , X. conica , X. fulvescens , X. ischnostroma , X. margaretae , X. minima , X. reinkingii var. microspora , X. siamensis , X. sihanonthii , X. subintraflava , X. thienhirunae , and X. vinacea . Their morphological and cultural characteristics are described and illustrated, and their ITS, α-actin and β-tubulin sequences were analysed. A dichotomous key to the 17 species of Xylaria occurring in Thailand is provided.

Novel species of fungi described in this study include those from various countries as follows: Antarctica , Cladosporium arenosum from marine sediment sand. Argentina , Kosmimatamyces alatophylus (incl. Kosmimatamyces gen. nov.) from soil. Australia , Aspergillus banksianus , Aspergillus kumbius , Aspergillus luteorubrus , Aspergillus malvicolor and Aspergillus nanangensis from soil, Erysiphe medicaginis from leaves of Medicago polymorpha , Hymenotorrendiella communis on leaf litter of Eucalyptus bicostata , Lactifluus albopicri and Lactifluus austropiperatus on soil, Macalpinomyces collinsiae on Eriachne benthamii , Marasmius vagus on soil, Microdochium dawsoniorum from leaves of Sporobolus natalensis , Neopestalotiopsis nebuloides from leaves of Sporobolus elongatus , Pestalotiopsis etonensis from leaves of Sporobolus jacquemontii , Phytophthora personensis from soil associated with dying Grevillea mccutcheonii. Brazil , Aspergillus oxumiae from soil, Calvatia baixaverdensis on soil, Geastrum calycicoriaceum on leaf litter, Greeneria kielmeyerae on leaf spots of Kielmeyera coriacea . Chile , Phytophthora aysenensis on collar rot and stem of Aristotelia chilensis. Croatia , Mollisia gibbospora on fallen branch of Fagus sylvatica. Czech Republic , Neosetophoma hnaniceana from Buxus sempervirens. Ecuador , Exophiala frigidotolerans from soil. Estonia , Elaphomyces bucholtzii in soil. France , Venturia paralias from leaves of Euphorbia paralias. India , Cortinarius balteatoindicus and Cortinarius ulkhagarhiensis on leaf litter. Indonesia , Hymenotorrendiella indonesiana on Eucalyptus urophylla leaf litter. Italy , Penicillium taurinense from indoor chestnut mill. Malaysia , Hemileucoglossum kelabitense on soil, Satchmopsis pini on dead needles of Pinus tecunumanii. Poland , Lecanicillium praecognitum on insects' frass. Portugal , Neodevriesia aestuarina from saline water. Republic of Korea , Gongronella namwonensis from freshwater. Russia , Candida pellucida from Exomias pellucidus , Heterocephalacria septentrionalis as endophyte from Cladonia rangiferina , Vishniacozyma phoenicis from dates fruit, Volvariella paludosa from swamp. Slovenia , Mallocybe crassivelata on soil. South Africa , Beltraniella podocarpi , Hamatocanthoscypha podocarpi , Coleophoma podocarpi and Nothoseiridium podocarpi (incl. Nothoseiridium gen. nov.) from leaves of Podocarpus latifolius , Gyrothrix encephalarti from leaves of Encephalartos sp., Paraphyton cutaneum from skin of human patient, Phacidiella alsophilae from leaves of Alsophila capensis , and Satchmopsis metrosideri on leaf litter of Metrosideros excelsa. Spain , Cladophialophora cabanerensis from soil, Cortinarius paezii on soil, Cylindrium magnoliae from leaves of Magnolia grandiflora , Trichophoma cylindrospora (incl. Trichophoma gen. nov.) from plant debris, Tuber alcaracense in calcareus soil, Tuber buendiae in calcareus soil. Thailand , Annulohypoxylon spougei on corticated wood, Poaceascoma filiforme from leaves of unknown Poaceae. UK , Dendrostoma luteum on branch lesions of Castanea sativa , Ypsilina buttingtonensis from heartwood of Quercus sp. Ukraine , Myrmecridium phragmiticola from leaves of Phragmites australis. USA , Absidia pararepens from air, Juncomyces californiensis (incl. Juncomyces gen. nov.) from leaves of Juncus effusus , Montagnula cylindrospora from a human skin sample, Muriphila oklahomaensis (incl. Muriphila gen. nov.) on outside wall of alcohol distillery, Neofabraea eucalyptorum from leaves of Eucalyptus macrandra , Diabolocovidia claustri (incl. Diabolocovidia gen. nov.) from leaves of Serenoa repens , Paecilomyces penicilliformis from air, Pseudopezicula betulae from leaves of leaf spots of Populus tremuloides . Vietnam , Diaporthe durionigena on branches of Durio zibethinus and Roridomyces pseudoirritans on rotten wood. Morphological and culture characteristics are supported by DNA barcodes., (© 2020 Naturalis Biodiversity Center & Westerdijk Fungal Biodiversity Institute.)

Oil palm decanter cake (OPDC) in the current study was converted to valuable products as laccase and manganese peroxidase (MnP) by an undescribed strain of the white-rot fungus, Pseudolagarobasidium sp. PP17-33. The optimization to enhance the production of enzymes through solid-state fermentation was performed using Plackett-Burman design and response surface methodology. The highest observed laccase was 5.841 U/gds and observed MnP was 5.156 U/gds, which enhanced yield by 2.59-fold and 1.94-fold from the non-optimization. The optimized medium (mg/g of OPDC) consisted of 0.852 mg CuSO 4 ·5H 2 O, 13.512 mg glucose, 2 mg yeast extract, 0.2 mg KH 2 PO 4 , 1.5 mg MgSO 4 ·7H 2 O, 0.01 mg FeSO 4 ·7H 2 O, 0.15 mg MnSO 4 ·H 2 O, 0.01 mg ZnSO 4 ·7H 2 O and 0.3 mg Tween 80 (pH 5.0) when incubated at 30 °C for 7 days. The most significant variables of laccase and MnP productions were CuSO 4 ·5H 2 O and glucose concentrations. This study is the first to report on the production of ligninolytic enzymes from OPDC waste using white-rot fungi. In addition, five different white-rot fungi, Coriolopsis aspera , C. retropicta , Dentipellis parmastoi , Nigroporus vinosus and Tyromyces xuchilensis, are newly observed producers of ligninolytic enzymes in Thailand. The results obtained from this study are significant not only for agro-industrial waste management but also for value-added enzyme production., Competing Interests: Conflict of interestThe authors declared no conflict of interest., (© King Abdulaziz City for Science and Technology 2019.)