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A total of 973 isolates of endophytic fungi were recovered from 1,144 tissue fragments of the six medicinal plant species belonging to 4 families collected in the Beijing Botanical Garden. Of these isolates 778 sporulated and were identified into 21 taxa by morphological characteristics. Among the taxa 11 belonged to Coelomycetes, 6 to Ascomycetes, and 4 to Hyphomycetes. Various numbers of endophytic fungi (5-8 taxa) were obtained from each plant. Alternaria alternata was the dominant species in the 6 plants, and Microsphaeropsis conielloides was also dominant in Eucommia ulmoides. There were high colonization rates (47.9%-63.1%) and isolation rates (0.7-0.93) of endophytic fungi, and they were conspicuously higher in twigs than those in leaves in the 6 plants examined. The colonization and isolation rates of endophytic fungi increased with the twig age. The results based on the analyses of cluster and Sorenson's similarity coefficients indicated that some endophytic fungi showed a certain degree of host and tissue preference.

Aims:  To characterize and identify a new taxol‐producing fungal strain HD86‐9 isolated from Taxus cuspidata in China. Methods and Results:  Taxol extracted from strain HD86‐9 was identified by HPLC and MS analyses. Strain HD86‐9 was cultured and its morphology and phenotypes were described. HD86‐9 displayed morphology most similar to that of Aspergillus niger but presented differences in the shape and size of the conidia. The growth evaluation showed that the maximal tolerable temperature of the new strain was 43°C, higher than that of the model Aspergillus niger. The 18S rDNA and the internal transcribed spacer region including the 5·8S rDNA of HD86‐9 were amplified by PCR; molecular analysis of these sequences revealed their high similarity of 98% to those of Aspergillus niger. Conclusions:  The morphology and molecular analysis identified HD86‐9 as a new variant of taxol‐producing endophytic fungi, and it was named Aspergillus niger var. taxi D.P. Zhou, K. Zhao and W.X. Ping, var. nov. Significance and Impact of the Study:  As the first report of a taxol‐producing variant of Aspergillus niger species, this study offers important information and a new resource for the production of an important anticancer drug by endofungus fermentation.

Bacteriocins have antimicrobial activities against food-spoiling bacteria and food-borne pathogens. Paracin 1.7, a bacteriocin synthesized by Lactobacillus paracasei HD1-7 isolated from Chinese sauerkraut juice, was studied. Following partial purification with ammonium sulfate precipitation, CM Sepharose Fast Flow, and Sephadex G-10 chromatography, the molecular weight of Paracin 1.7 was about 10 kDa based on Tricine-SDS-PAGE results. A 2.87 fold purified bacteriocin was produced, reaching a final yield of 39.93% and the specific activity of 1.56 × 103 AU/mg. The N-terminal amino acid sequence of Paracin 1.7 was VSNTFFA, and the LC/LTQ results revealed that the N-terminal amino acid sequence was similar to that of ABC-type oligopeptide transport system protein and N-acetylmuramoyl-L-alanine amidase. Paracin 1.7 was sensitive to protease K, had antimicrobial activities at a broad pH range (3.0–8.0), and was heat resistant (121 °C for 20 min). Paracin 1.7 from Lactobacillus paracasei HD1-7 is a novel bacteriocin that has potential applications in food preservation.

High-throughput sequencing and GC-MS (gas chromatography-mass spectrometry) were jointly used to reveal the bacterial succession and metabolite changes during flax (Linum usitatissimum L.) retting. The inoculation of Bacillus cereus HDYM-02 decreased bacterial richness and diversity. This inoculum led to the replacement of Enterobacteriaceae by Bacillaceae. The level of aerobic Pseudomonadaceae (mainly Azotobacter) and anaerobic Clostridiaceae_1 gradually increased and decreased, respectively. Following the addition of B. cereus HDYM-02, the dominant groups were all degumming enzyme producers or have been proven to be involved in microbial retting throughout the entire retting period. These results could be verified by the metabolite changes, either degumming enzymes or their catalytic products galacturonic acid and reducing sugars. The GC-MS data showed a clear separation between flax retting with and without B. cereus HDYM-02, particularly within the first 72 h. These findings reveal the important bacterial groups that are involved in fiber retting and will facilitate improvements in the retting process.

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To apply the fundamental principles of genome shuffling in breeding of taxol-producing fungi, Nodulisporium sylviform was used as starting strain in this work. The procedures of protoplast fusion and genome shuffling were studied. Three hereditarily stable strains with high taxol production were obtained by four cycles of genome shuffling. The qualitative and quantitative analysis of taxol produced was confirmed using thin-layer chromatography (TLC), high performance liquid chromatography (HPLC) and LC-MS. A high taxol producing fungus, Nodulisporium sylviform F4-26, was obtained, which produced 516.37 microg/L taxol. This value is 64.41% higher than that of the starting strain NCEU-1 and 31.52%-44.72% higher than that of the parent strains.