Six indole alkaloids with various levels of prenylation were isolated from the thermophilic fungus Talaromyces thermophilus strain YM3-4. Their structures were identified by NMR and MS spectroscopic analyses. Compounds 1 and 2 are new analogues of the key versatile precursor notoamide E. Compound 3 is a novel analogue of preechinulin, and compound 4 was reported as a natural occurring cyclo(glycyltryptophyl) for the first time. The metabolite profile of this thermophilic organism displayed a biosynthetic pathway for talathermophilins.

The putative key biosynthetic intermediates of prenylated indole alkaloids have long been proposed but never isolated. Two such alkaloids, named talathermophilins A and B (1 and 2), were isolated from a thermophilic fungus Talaromyces thermophilus strain YM1-3 and were identified by NMR and MS spectroscopic analyses. The ratio of 1 and 2 in the culture broths was unexpectedly rather constant (about 2:3), which even remained unchanged despite the addition of exogenous 1 or 2, suggesting that talathermophilins might be of special function for the extremophilic fungus.

Two hundred and six bacterial isolates were obtained from leaf, flower and stem of three healthy plants, Euphorbia pulcherrima Willd, Pyrethrum cinerariifolium Trev. and Heracleum candicans Wall. The nematicidal activity experiment showed that a total of 92 isolates displayed activity against Caenorhabditis elegans (Maupas) Dougherty, and 70 isolates resulted active against Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle. Strain LCB-3 exhibited the strongest nematicidal activity against both two nematodes. According to the 16S rDNA, the strain LCB-3 was identified as Brevundimonas diminuta. Based on bioassay-guided fractionation, a nematicidal metabolite (R)-(-)-2-ethylhexan-1-ol was obtained from LCB-3. The median lethal concentrations (LC 50 ) of the compound were 542.0 mg l -1 against C. elegans and 168.1 mg l -1 against B. xylophilus 48 h after treatment.

Two novel thermophilic, spore-forming bacterial strains, T-11T and E-112T, were isolated from hot springs in Tengchong and Eryuan counties of Yunnan province in south-west China. The strains were Gram-stain-positive rods, occurring singly or in chains. Growth of strain T-11T was observed between 30 and 75 °C (optimum 50 °C) and at pH 7–11 (optimum pH 8.5), while the temperature range for strain E-112T was 35–70 °C (optimum 55 °C) and the pH range was 7.0–11.0 (optimum pH 8.0). The DNA G+C contents of strains T-11T and E-112T were 41.1 and 42.6 mol%, respectively. On the basis of 16S rRNA gene sequence similarity, the two strains were shown to be related most closely to Anoxybacillus species. The chemotaxonomic characteristics [predominant isoprenoid quinone menaquinone 7 (MK-7); major fatty acids iso-C15 : 0 and iso-C17 : 0] also supported the affiliation of strains T-11T and E-112T to the genus Anoxybacillus. The results of DNA–DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strains T-11T and E-112T from Anoxybacillus species with validly published names. Strains T-11T and E-112T therefore represent two novel species, for which the names Anoxybacillus tengchongensis sp. nov. (type strain T-11T =CCTCC AB209237T =KCTC 13721T) and Anoxybacillus eryuanensis sp. nov. (type strain E-112T =CCTCC AB209236T =KCTC 13720T) are proposed.

The geothermal sites near neutral and alkalescent thermal springs in Tengchong Rehai National Park were examined through cultivation-dependent approach to determine the diversity of thermophilic fungi in these environments. Here, we collected soils samples in this area, plated on agar media conducive for fungal growth, obtained pure cultures, and then employed the method of internal transcribed spacer (ITS) sequencing combined with morphological analysis for identification of thermophilic fungi to the species level. In total, 102 strains were isolated and identified as Rhizomucor miehei, Chaetomium sp., Talaromyces thermophilus, Talaromyces byssochlamydoides, Thermoascus aurantiacus Miehe var. levisporus, Thermomyces lanuginosus, Scytalidium thermophilum, Malbranchea flava, Myceliophthora sp. 1, Myceliophthora sp. 2, Myceliophthora sp. 3, and Coprinopsis sp. Two species, T. lanuginosus and S. thermophilum were the dominant species, representing 34.78% and 28.26% of the sample, respectively. Our results indicated a greater diversity of thermophilic fungi in neutral and alkaline geothermal sites than acidic sites around hot springs reported in previous studies. Most of our strains thrived at alkaline growth conditions.