Staurosporine from the endophytic Streptomyces sp. strain CNS-42 acts as a potential biocontrol agent and growth elicitor in cucumber.

Chinese medicinal plants and their surrounding rhizospheric soil serve as promising sources of actinobacteria. A total of 180 actinobacteria strains were isolated from the rhizosphere soil, leaves, stems, and roots of nine selected plants and have been identified as potential biocontrol agents against Fusarium oxysporum f. sp. cucumerinum. An endophytic strain CNS-42 isolated from Alisma orientale showed the largest zone of inhibition demonstrating a potent effect against F. oxysporum f. sp. cucumerinum and a broad antimicrobial activity against bacteria, yeasts, and other pathogenic fungi. The in vivo biocontrol assays showed that the disease severity index was significantly reduced (P < 0.05), and plant shoot fresh weight and height increased greatly (P < 0.05) in plantlets treated with strain CNS-42 compared to the negative control. This isolate was identified as Streptomyces sp. based on cultural, physiological, morphological characteristics, and 16S rRNA gene analysis. Further bioassay-guided isolation and purification revealed that staurosporine was responsible for its antifungal and plant growth promoting activities and the latter property of staurosporine is reported for the first time. The in vivo assay was further performed and indicated that staurosporine showed good growth promoting effect on the plant shoot biomass of cucumber. This is the first critical evidence identifying CNS-42 as a biocontrol agent for the soil borne pathogen, F. oxysporum f. sp. cucumerinum.

[Endophytic bacterial diversity in Codonopsis pilosula, Ephedra sinica, and Lamiophlomis rotate: a study with LH-PCR].

To investigate the endophytic bacterial diversity in the three medicinal plant species Codonopsis pilosula, Ephedra sinica, and Lamiophlomis rotata in Ganzi of Sichuan, Southwest China, the total DNA of the three species were extracted by stringent surface sterilization, and studied with length heterogeneity-PCR (LH-PCR) method. For the same plant species, their root-, stem-, and leaf LH-PCR profiles were in a high level of similarity, with little differences in band richness. However, there existed great differences in the LH-PCR profiles among different plant species. C. pilosula had the biggest band richness, followed by E. sinica, and L. rotata. In the three plant species, the endophytic bacteria with an approximately 474 bp DNA length were dominant. The endophytic bacterial diversity of the plants was negatively correlated with rhizosphere soil available phosphorus content, but positively correlated with rhizosphere soil pH. Elevation and rhizosphere soil total nitrogen content were the important environmental factors affecting the distribution of enophytic bacteria in these plant species. The information of population diversity obtained from LH-PCR could more intuitively reflect the differences of bacterial diversity among different plant species, and thus, LH-PCR would be available to be used for analyzing the endophytic bacterial diversity in medicinal plants, providing information and guidance for the further isolation of microbial resources.

[Active ingredients and efficacies of Ganoderma lucidum cultivated on non-medicinal parts of Chinese medicinal herbs].

OBJECTIVE: Ganoderma lucidum was cultivated on non-medicinal parts of Salvia miltiorrhiza, Chrysanthemum morifolium, Ptatycodgn grandlfiorum, as all are Chinese traditional herbal medicines. We studied the changes of active ingredients and efficacies of the Ganoderma lucidum fruit bodies. METHODS: The agronomic characters, polysaccharide and terpene contents, acute toxicity and efficacy of Ganoderma lucidum grown on the non-medicinal part of the three materials were compared with that grown on the ordinary formula group (OF. G) which was composed of corn cob, cotton seed shell. RESULTS: Biological conversion efficiencies of the Ganoderma lucidum fruit body using non-medicinal parts were higher than that of using the ordinary formula group (OF. G), though growth periods became longer; Contents of active ingredients were all improved except that the terpene content of the Salvia miltiorrhiza group was decreased. Both polysaccharide and terpene from the Chrysanthemum morifolium group were the highest, contents of which were respectively 2.47% and 0.79%; Acute toxicity test showed that Ganoderma lucidum fruit bodies were all with low toxicities. Mice maximum tolerance dose were 100 g/kg weight. In hemolysin test and sleeping promotion test, the Chrysanthemum morifolium group showed better effect than the ordinary formula group (OF. G). In anti-fatigue test, only the ordinary formula group (OF. G) proved to be more effective. CONCLUSION: It's feasible to cultivate Ganoderma lucidum and active ingredients and efficacies of Ganoderma lucidum have been changed using the non-medicinal parts of Chinese medicinal herbs.

[Effects of Armillariella tabescens polysaccharide IPS-B2 on activity of mouse peritoneal macrophages and transcription of related gene].

OBJECTIVE: To observe the effect of IPS-B2 on mouse peritoneal macrophages and the transcription of IL-1beta, IL-6, TNF-alpha and iNOS. METHOD: ELISA method and Griess method were used to detect the effect of mouse peritoneal macrophages produce cytokines IL-1beta, IL-6, TNF-alpha and cytotoxic effectors NO. The transcription of IL-1beta, IL-6, TNF-alpha and iNOS was detected by real-time RT-PCR method. RESULT: IPS-B2 could not promote mouse peritoneal macrophage production, but it could significantly improve the IL-1beta, IL-6, TNF-alpha content in mouse peritoneal macrophages culture supernatant, and increase the gene expression of IL-1beta, IL-6, TNF-alpha and iNOS. CONCLUSION: IPS-B2 can enhance the ability of peritoneal macrophages to excrete bioactive substances and promote the transcription of bioactive substances to antitumor.

[AFLP analysis for genetic diversity of Ganoderma].

OBJECTIVE: To investigate the genetic diversity of Ganoderma cultivars provided for the genuineness study, germ-plasm resource identification, genetic relationship study, breeding, introduction and cultivante of Ganoderma strains. METHOD: With the software of NTSYSpc 2. 1, 24 materials, of G. lucidum and G. sinense, were studied using AFLP to construct the dendrogram. RESULT: There were 177 polymorphic bands with 14 primer combinations. And all materials could be identified with AFLP. CONCLUSION: There actually existed much genetic diversity at the molecular level among the germplasm resources of Ganoderma strains, and all the strains were clustered into G. lucidum group and G. sinense group at the similarity coefficient 0. 676.