Sphingomonas hylomeconis sp. nov., isolated from the stem of Hylomecon japonica.

A yellow-pigmented bacterium, designated strain GZJT-2T, was isolated from the stem of Hylomecon japonica (Thunb.) Prantl et Kündig collected from Taibai Mountain in Shaanxi Province, north-west China. Cells of strain GZJT-2T were Gram-reaction-negative, strictly aerobic, rod-shaped, non-spore-forming and non-motile. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain GZJT-2T was a member of the genus Sphingomonas, with sequence similarities of 92.1-96.9 % to type strains of recognized species of the genus Sphingomonas (92.1 % to Sphingomonas oligoaromativorans SY-6T and 96.9 % to Sphingomonas oligophenolica JCM 12082T). Strain GZJT-2T contained ubiquinone-10 (Q-10) as the predominant respiratory quinone and sym-homospermidine as the major polyamine. The major cellular fatty acids were summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C14 : 0 2-OH. Phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine, sphingoglycolipid, four unidentified phospholipids, an unidentified aminolipid and four unidentified lipids were detected in the polar lipid profile. The DNA G+C content was 62.5 ± 0.3 mol%. On the basis of data from phenotypic, phylogenetic and DNA-DNA relatedness studies, strain GZJT-2T is considered to represent a novel species of the genus Sphingomonas, for which the name Sphingomonas hylomeconis sp. nov. is proposed. The type strain is GZJT-2T ( = CCTCC AB 2013304T = KCTC 42739T).

Sphingobium endophyticus sp. nov., isolated from the root of Hylomecon japonica.

A yellow-pigmented bacterium, designated strain GZGR-4(T), was isolated from the root of Hylomecon japonica (Thunb.) Prantl et Kündig collected from Taibai Mountain in Shaanxi Province, north-west China. Cells of strain GZGR-4(T) were Gram-negative, rod-shaped, strictly aerobic, non-endospore-forming and non-motile. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain GZGR-4(T) is a member of the genus Sphingobium, exhibiting the highest sequence similarity to Sphingobium aromaticiconvertens DSM 12677(T) (97.3 %). 16S rRNA gene sequence similarities between strain GZGR-4(T) and the type strains of other Sphingobium species with validly published names ranged from 93.4-96.5 %. The predominant respiratory quinone of strain GZGR-4(T) was ubiquinone-10 (Q-10) and the major cellular fatty acids were summed feature 8 (comprising C18:1 ω7c and/or C18:1 ω6c), summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c), C16:0 and C14:0 2-OH. Spermidine was the major polyamine. The polar lipid profile consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, sphingoglycolipid, one unidentified phosphoglycolipid, one unidentified phospholipid, one unidentified aminolipid and one unidentified lipid. The DNA G+C content was 63.6 mol%. DNA-DNA relatedness for strain GZGR-4(T) with respect to its closest phylogenetic relative S. aromaticiconvertens DSM 12677(T) was 22.6 ± 5.3 %. On the basis of the polyphasic taxonomic data presented, strain GZGR-4(T) is considered to represent a novel species of the genus Sphingobium, for which the name Sphingobium endophyticus sp. nov. is proposed. The type strain is GZGR-4(T) (=CCTCC AB 2013305(T) = KCTC 32447(T)).

An endophytic sanguinarine-producing fungus from Macleaya cordata, Fusarium proliferatum BLH51.

Fermentation processes using sanguinarine-producing fungi other than Macleaya cordata may be an alternative way to produce sanguinarine (SA), which is a quaternary benzo[c]phenanthridine alkaloid possessing antibacterial, anthelmintic, and anti-inflammatory properties. In this study, a SA-producing endophytic fungus strain BLH51 was isolated from the leaves of M. cordata grown in the Dabie Mountain, China. Strain BLH51 produced SA when grown in potato dextrose liquid medium. The amount of SA produced by this endophytic fungus was quantified to be 178 µg/L by HPLC, substantially lower than that produced by the host tissue. The fungal SA--which was analyzed by thin layer chromatography and high-performance liquid chromatography--was shown to be identical to authentic SA. Strain BLH51 was identified as Fusarium proliferatum based on the morphological characteristics and nuclear ribosomal DNA ITS sequence analysis. To the best of our knowledge, this is the first report concerning the isolation and identification of endophytic SA-producing fungi from the host plant, which further proved that endophytic fungi are valuable reservoirs of bioactive compounds.

[Isolation and identification of an antimicrobial endophytic actinomycete from Macleaya cordata].

OBJECTIVE: An antimicrobial endophytic actinomycete strain was isolated from the root of Macleaya cordata, and its phylogenetic position was also investigated. METHODS: Endophytic actinomycetes were isolated from the root of Macleaya cordata growing in Dabie Mountain by tablet coating method. Antimicrobial activities of endophytic actinomycetes were determined by the agar block method,and then a potential strain was identified by morphology, biochemical characterization and molecular methods. RESULTS: A total of 15 strains of endophytic actinomycetes were isolated from the samples, six of them had antimicrobial activity to the test strains which accounts for 40% of all strains. Among the six strains,the strain BL7 was found to produce antibiotic substances which showed significant inhibitory effects on Staphylococcus aureus and Bacillus subtilis,with a formed inhibition zone of 29 mm and 20 mm respectively. Based on the morphology, biochemical characterization and 16S rDNA sequence analysis,the strain BL7 was preliminary identified as Streptomyces mobaraensis. CONCLUSION: Some members of Streptomyces genus have a very wide application prospect in medicine. This is the first report that Streptomyces mobaraensis strain was isolated from Macleaya cordata, and this study provides basis for the further exploration of the strain.

[Isolation of endophytic fungi from Macleaya cordata and screening of sanguinarine-producing strains].

Endophytic fungi were isolated from Macleaya cordata growing in Dabie Mountain by agar-block method, and then the endophytic fungi were grouped into different types based on their morphological characteristics, and thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were employed to determine whether the metabolic substances contained sanguinarine or not, and then preliminarily identified by morphological method. The results showed that the leaves hosted the largest number of endophytes (96 isolates) followed by the stems (57 isolates) and finally the roots (28 isolates), respectively. Based on morphological characteristics the endophytic fungi were grouped into 26 types in our study. TLC and HPLC results showed that there was sanguinarine in the metabolic substances of BLH 51 strain. According to the morphological characteristic, the BLH 51 strain was identified as Fusarium proliferatum. All these indicated that the medicinal plant M. cordata harbors abundant endophytes, which could be a new source for the search of active secondary metabolites.