| The chemical constituents and their bioactivities of two endophytic fungi isolated from Melia azedarach, two endophytic bacteria of Salvia miltiorrhiza Bunge and one symbiotic fungus associated with D. armandi on host P. armandi were studied.82compounds were obtained from the cultures of the microbial materials. The structures were elucidated based on spectral data(1H-NMR,13C-NMR,1H-1H COSY,HMQC,HMBC,NOESY and MS). We also report the biotransformation of paeonol by the white-rot Basidiomycete Coriolus versicolor. The results are concluded as follows:1. Two new alkaloids,12β-hydroxy-13α-methoxy verruculogen TR-2(1-6),3-hydroxyfumiquinazoline A (1-16) and37known compounds:fumitremorgin C (1-1), cyclotryprostatin A (1-2), cyclotryprostatin B (1-3), verruculogen TR-2(1-4),12β-hydroxy-verruculogen TR-2(1-5), fumitremorgin B (1-7), verruculogen (1-8), tryprostatin A (1-9), cyclo-L-tryptophyl-L-proline (1-10), terezine D (1-11), fumiquinazolines F (1-12), fumiquinazolines G (1-13), fumiquinazolines D (1-14), fumiquinazolines A (1-15),3-hydroxyfumiquinazolines A (1-16),6-methoxylspirotryprostatins B (1-17), spiro[5H,10H-dipyrrolo[1,2-a:1',2'-d]pyrazine-2(3H),2'-[2H]-indole]-3',5,10(1'H)-trione (1-18), pseurotin A (1-19), pseurotin A1(1-20), tryptoquivaline O (1-21), fumigaclavine B (1-22), bisdethiobis(methylthio)gliotoxin (1-23), cyclo-(Pro-Gly)(1-24), cyclo-(Pro-Ala)(1-25), cyclo-(D-Pro-L-Ala)(1-26), cyclo-(Pro-Ser)(1-27), cyclo-(Ser-trans-4-OH-Pro)(1-28), cyclo-(Leu-4-OH-Pro)(1-29), cyclo-(Ala-trans-4-OH-Pro)(1-30), cyclo-(cis-OH-D-Pro-L-Phe)(1-31), cyclo-(Gly-Phe)(1-32), cyclo-(Pro-trans-4-OH-Pro)(1-33), cyclo-(Gly-Ala)(1-34), uracil (1-35),4,8-dihydroxy-l-tetralone (1-36), trans-(3RS,4RS)-3,4-Dihydro-3,4,8-trihydroxynaphthalen-1(2H)-one (1-37), cis-(3RS,4SR)-3,4-Dihydro-3,4,8-trihydroxy-naphthalen-1(2H)-one (1-38) and helvolic acid (1-39) were isolated from the fermentation broth of Aspergillus fumigatus LN-4, an endophytic fungus isolated from the stem bark of Melia azedarach.These isolated compounds were evaluated for in vitro antifungal activities against phytopathogenic fungi, toxicity to brine shrimps, and antifeedant activities against armyworm larvae(Mythimna separata Walker). Among them, sixteen compounds showed potent activities against8phytopathogenic fungi, and four of them,1-6,1-7,1-8and1-39, exhibited antifungal activities with MIC values of6.25-50μg/ml, which were comparable to two positive controls carbendazim and hymexazol. In addition, of eighteen that exerted moderate lethality activity toward brine shrimps, both compounds1-7and1-8showed significant toxicities with their corresponding median lethal concentration (LC50) values of13.6and15.8μg/ml. Furthermore, among nine metabolites that were found to possess antifeedant activity against armyworm larvae, both compounds1-7,1-8and1-15gave best activity with the antifeedant index (AFI)50.0%,55.0%and45%, respectively.2. Eleven known compounds:cyclo-(Pro-Gly)(2-1), cyclo-(Pro-Ala)(2-2), cyclo-(D-Pro-L-Ala)(2-3), cycl-(Ala-4-OH-Pro)(2-4), cyclo-(Ala-Gly)(2-5), cyclo-(Phe-Gly)(2-6),4-methoxyphenylacetic acid (2-7), linoleic acid (2-8), trielaidin (2-9), cerevisterol (2-10) and ergosterol peroxide (2-11) were isolated from the organic extract of fermentation broths of Fusarium sp. LN-11, an endophytic fungus isolated from the leaves of Melia azedarach. Compound2-4was shown to be moderate active toward brine shrimp larvae at a concentration of100μg/ml with mortality rate of72.8%.3. The antioxidant, antibacterial and antifungal activities by the DPPH method, the micro-broth dilution method and the Poison Food Technique of eight endophytic bacterial stains, which isolated from the roots of Salvia miltiorrhiza Bunge, were tested in vitro. The results showed that Pseudomonas brassicacearum subsp. Neoaurantiaca (B1) and Bacillus aryabhattai (B5) had more effective at antioxidant, antibacterial and antifungal activities than other endophtic bacteria.4. A novel alkaloid Neoaurpeptide (3-1) and11known compounds:cyclo-(Gly-L-Ala)(3-2), cyclo-(L-Ala-L-Ala)(3-3), cyclo-(L-Pro-Gly)(3-4), cyclo-(L-Pro-L-Ser)(3-5), cyclo-(L-Ala-trans-4-hydroxy-L-Pro)(3-6), cyclo-(L-Val-L-Pro)(3-7), cyclo-(Gly-L-Tyr)(3-8), cyclo-(L-Ala-L-Tyr)(3-9), cyclo-(L-Tyr-trans-4-hydroxy-L-Pro)(3-10),3-methyl hydantoin (3-11) and2-piperidinone (3-12) were isolated from the culture of Pseudomonas brassicacearum subsp. Neoaurantiaca, an endophytic bacterium found inside the tissue of Salvia miltiorrhiza Bunge. Compounds3-1,3-6,3-8,3-9and3-10exerted moderate lethality activity toward brine shrimps, and were found to show significant activities with LC50values of68.2,46.1,71.0,71.0and79.5μg/ml, respectively. In addition, seven compounds showed potent activities against3phytopathogenic fungi which can cause Danshen root rot disease, and3-5showed remarkable antifungal activity with MIC values ranging from25to50μg/ml.5. Six known compounds:cyclo-(Pro-Gly)(4-1), cyclo-(Ala-4-OH-Pro)(4-2), cyclo-(Leu-4-OH-Pro)(4-3), cyclo-(Ala-Gly)(4-4), uracil (4-5) and urea (4-6) were isolated from the fermentation broth of Bacillus aryabhattai, an endophytic bacterium found inside the tissue of Salvia miltiorrhiza Bunge. Compound4-2exerted moderate lethality activity toward brine shrimps, and was found to show significant activities with LC50values of46.1μg/ml. Compounds4-2and4-3showed potent activities against3phytopathogenic fungi which can cause Danshen root rot disease, exhibited antifungal activities with MIC values of50-100μg/ml,6. Three toxins,6-methoxymethyleugenin (5-1), maculosin (5-5) and cerevisterol (5-12), together with11other compounds:6-hydroxymethyleugenin (5-2),3-methoxy-6,8-dihydroxy-3-methyl-3,4-dihydroisocoumarin (5-3),4-hydroxyphenylethanol (5-4), scytalone (5-6),4-methoxyphenylacetic acid (5-7), succinic acid (5-8), ergosterol peroxide (5-9),22E,24R-5α,6α-epoxyergosta-8(14),22-diene-3β,7α-diol (5-10), glycerol-1-monooleate (5-11), ergosterol peroxide3-O-β-D-glucopyranoside (5-13) and22E,24R-ergosta-7,22-diene-3β,5α,6β,9α-tetraol (5-14) have been isolated from the ethyl acetate extracts of the cultures of Leptographium qinlingensis, an ophiostomatoid fungal pathogen associated with a forest pest Dendroctonus armandi, which causes enormous deaths of its host trees Pinus armandi. Phytotoxic test showed that, after5days, the treated groups were almost completely wilted, and their lethal rates are above95%for these three compounds. Similarly, three toxins can reduced chlorophyll content of two-year-old field seedlings.7. Biotransformation of substrate paeonol was investigated with the white-rot basi diomycete Coriolus versicolor. Two biotransformed products,2,4-dihydroxyacetophenone (6-2) and2,5-dihydroxy-4-methoxyacetophenone (6-3), were isolated and identified by spectral methods. Compound6-3showed higher antioxidant, antibacterial, antifungal a ctivities than substrate paeonol.
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