Evaluation of the phytoremediation potential of dominant plant species growing in a chromium salt-producing factory wasteland, China.

The metal contents of the soil and plant tissues in a large chromium salt-producing factory wasteland were determined to assess the properties of soil contamination and to identify plant species accumulating a range of heavy metals. Total metal contents in the factory soils presented a high heterogeneity, and the principal contaminants were Cd and Cr. All plant species examined were metal-tolerant, but to different extents. Especially, the maximum accumulation of Cd (15.61 mg kg-1) and Cr (925.07 mg kg-1) was found in Melia azedarach L. Subsequently, the Cd and Cr bioaccumulation and diverse physiological properties of M. azedarach seedlings exposed to different concentrations of Cd(II), Cr(VI), or Cd(II) + Cr(VI) in nutrient solutions were further investigated. All treated seedlings were able to survive under heavy metal stress, and the accumulation of both metals in plant tissues increased with elevation of metal exposure strength. M. azedarach showed a BCF greater than 147.56 for Cd and 36.76 for Cr. Meanwhile, the TF was lower than 0.25 for Cd and 0.32 for Cr. The highest bioaccumulation in root tissues was 2708.03 mg kg-1 Cd and 824.65 mg kg-1 Cr for seedlings cultured with 20 mg L-1 Cd(II) or 20 mg L-1 Cr(VI). Cd and Cr increased each other's uptake in seedlings although a reduced accumulation in roots occurred when exposed to the highest concentration of Cd(II) + Cr(VI) treatment (20 mg L-1). At either level of concentration, the degree of plant growth inhibition and oxidative damage caused by heavy metals was Cd(II) + Cr(VI) > Cr(VI) > Cd(II). Superoxide dismutase and peroxidase exhibited positive and effective responses to low-Cd(II) or Cr(VI) concentration stress, but their activities decreased with increasing metal exposure strength. The behavior of the non-enzymatic antioxidants (GSH, soluble protein, and proline) in plant involved in the detoxification of ROS induced by metal exposure was correlated well with higher Cd and Cr accumulations. Here, the potentiality of M. azedarach with the capacity to accumulate and stabilize Cd/Cr in metal-contaminated soil by phytoremediation process has been explored.

Diversity and bioactivities of fungal endophytes from Distylium chinense, a rare waterlogging tolerant plant endemic to the Three Gorges Reservoir.

BACKGROUND: The present study involves diversity and biological activities of the endophytic fungal community from Distylium chinense, a rare waterlogging tolerant plant endemic to the Three Gorges Reservoir. This study has been conducted hypothesizing that the microbial communities in the TGR area would contribute to the host plant tolerating a range of abiotic stress such as summer flooding, infertility, drought, salinity and soil erosion etc., and they may produce new metabolites, which may possess plentiful bioactive property, especially antioxidant activity. Therefore in the current study, the antioxidant, antimicrobial and anticancer activities of 154 endophytes recovered from D. chinense have been investigated. Furthermore, the active metabolites of the most broad-spectrum bioactive strain have also been studied. RESULTS: A total of 154 fungal endophytes were isolated from roots and stems. They were categorized into 30 morphotypes based on cultural characteristics and were affiliated with 27 different taxa. Among these, the most abundant fungal orders included Diaporthales (34.4%) and Botryosphaeriales (30.5%), which were predominantly represented by the species Phomopsis sp. (24.7%) and Neofusicoccum parvum (23.4%). Fermentation extracts were evaluated, screening for antioxidant, antimicrobial and anticancer activities. Among the 154 isolates tested, 99 (64.3%) displayed significant antioxidant activity, 153 (99.4%) exhibited inclusive antimicrobial activity against at least one tested microorganism and 27 (17.5%) showed exclusive anticancer activity against one or more cancer cell lines. Specifically, the crude extract of Irpex lacteus DR10-1 exhibited note-worthy bioactivities. Further chemical investigation on DR10-1 strain resulted in the isolation and identification of two known bioactive metabolites, indole-3-carboxylic acid (1) and indole-3-carboxaldehyde (2), indicating their potential roles in plant growth promotion and human medicinal value. CONCLUSION: These results indicated that diverse endophytic fungal population inhabits D. chinense. One of the fungal isolate DR10-1 (Irpex lacteus) exhibited significant antioxidant, antimicrobial and anticancer potential. Further, its active secondary metabolites 1 and 2 also showed antioxidant, antimicrobial and anticancer potential.

An endophytic fungus from Trichoderma harzianum SWUKD3.1610 that produces nigranoic acid and its analogues.

The objective of this study was to determine whether endophytic fungi, isolated from Kadsura angustifolia produce nigranoic acid and its highly oxygenated derivatives. From the 426 endophytic fungi screened, Trichoderma harzianum SWUKD3.1610 was detected to have a component with the same TLC R f value and HPLC retention time as authentic nigranoic acid. This component was further confirmed as nigranoic acid by investigating the chemical composition of the fungal extracts. Besides (1), one new triterpenoid, 7ß- schinalactone C (2), and two known minor compounds were isolated and characterized by HRESIMS, 1D and 2D NMR spectroscopic methods. Our study indicates that endophytic fungus may play an important role in increasing the quality of the crude drugs from Chinese medicinal plant K. angustifolia. This study is the first to isolate, characterize, and identify schitriterpenes-producing Trichoderma spp.

Enhanced production of unusual triterpenoids from Kadsura angustifolia fermented by a symbiont endophytic fungus, Penicillium sp. SWUKD4.1850.

Highly oxygenated schitriterpenoids are interesting for study of their structures, bioactivities and synthesis. From Kadsura angustifolia fermented by an associated symbiotic endophytic fungus, Penicillium sp. SWUKD4.1850, nine undescribed triterpenoids, kadhenrischinins A-H, and 7ß-schinalactone C together with four known triterpenoids, henrischinins A and B, schinalactone C and nigranoic acid were isolated and established by the extensive 1D-, 2D-NMR, HR-ESI-MS and ECD data analysis. Except nigranoic acid, all these metabolites have been first detected in non-fermented K. angustifolia. Structurally, kadhenrischinins A-D belong to the relatively rare class of highly oxygenated schitriterpenoids that contain a unique 3-one-2-oxabicyclo [3,2,1]-octane motif, while kadhenrischinins E-H feature a cyclopentane ring in a side chain rarely found in the family Schisandraceae. These results indicated that fermentation of K. angustifolia with SWUKD4.1850 induced the production of highly oxygenated schitriterpenoids from nigranoic acid, which provided a guidance to obtain desired compounds from those plants initially thought not to produce. This is the first report on the fermentation of K. angustifolia medical plant and the first discovery of highly oxygenated schitriterpenoids by microbial technology.

Effects of an Endophytic Fungus Umbelopsis dimorpha on the Secondary Metabolites of Host-Plant Kadsura angustifolia.

Fungal endophytes live widely inside plant tissues and some have been revealed to provide benefits to their host and ecological environment. Considering the fact that endophytes are engaged in remarkably stable long-term interactions with the host for their whole life cycle, it's conceivable that both partners have substantial influence on each other's metabolic processes. Here, we investigated the fermented products of an endophytic fungus Umbelopsis dimorpha SWUKD3.1410 grown on host-plant Kadsura angustifolia and wheat bran, respectively, to assess the impact of SWUKD3.1410 on the secondary metabolites of K. angustifolia. Twenty compounds (1-20) were isolated and identified as 11 schitriterpenoids (1-9, 17-18), two lignans (10, 20), two sesquiterpenoids (11-12), one trinorsesquiterpenoid (13), one monoterpene (14), one sterol (19), and two simple aromatic compounds (15-16) by the extensive 1D-, 2D-NMR and HR-ESI-MS data analysis. Except for nigranoic acid (1), compounds 2-19 have been firstly found from K. angustifolia. Of them, metabolites 2, 11, and 14 were identified to be new. Obtained results indicated that U. dimorpha SWUKD3.1410 could not only produce the same/similar components as its host does, and modify the host-plant components, but also enhance the production of these highly oxygenated schitriterpenoids/schinortriterpenoids in plants. This study suggested an interesting prospective for setting up alternative processing techniques to improve the quality of crude drugs derived from K. angustifolia and increase their values.

Fluorescence spectra of cardiac myosin and in vivo experiment: studies on daunorubicin-induced cardiotoxicity.

OBJECTIVES: The objective of this study was to investigate the interaction of daunorubicin (DNR) and cardiac myosin (CM) and the changes in mice hearts to exhibit DNR-induced cardiotoxicity. MATERIALS AND METHODS: The interaction between DNR and CM was expressed using fluorescence quenching at pH 4.0-9.0 and 15-37 °C. DNR-induced cardiotoxicity was studied using in vivo experiment. Forty groups mice were used control group in which mice were treated with DNR orally, and three DNR-treated groups in which mice were injected intraperitoneally with DNR at seven bolus doses of 2.0, 4.0, and 6.0 mg/kg body weight, respectively. Heart indices and myocardial enzyme levels were obtained by histopathological and biochemical analysis. RESULTS: The fluorescence quenching mechanism of DNR-CM complex was observed to be a static procedure at 20 °C (pH 7.4), and weakly acidic environment (pH 4.0-6.0) or higher temperature (30-37 °C) promoted the interaction between DNR and CM, causing variations in conformation and normal physiological functions of CM. Thermodynamic studies demonstrated that the binding of DNR to CM was a spontaneous process driven by entropy. It also indicated that hydrophobic interaction and hydrogen bonds may play essential roles in the combination of DNR with CM. In addition, 4.0-6.0 mg/kg DNR-treated mice exhibited obvious histopathological lesion, increase in myocardial enzyme level, and reductions in blood cell count. CONCLUSION: Our results are valuable for better understanding the particular mode of DNR-CM interaction, and are important to have a deeper insight into the DNR-induced cardiotoxicity.