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1.
Myrothecium verrucaria and Fusarium compactum were isolated from diseased Orobanche ramosa plants collected in southern Italy to find potential biocontrol agents of this parasitic weed. Both fungi grown in liquid culture produced metabolites that inhibited the germination of O. ramosa seeds at 1-10 muM. Eight metabolites were isolated from M. verrucaria culture extracts. The main metabolite was identified as verrucarin E, a disubstituted pyrrole not belonging to the trichothecene group. Seven compounds were identified by spectroscopic methods as macrocyclic trichothecenes, namely, verrucarins A, B, M, and L acetate, roridin A, isotrichoverrin B, and trichoverrol B. The main metabolite produced by F. compactum was neosoloaniol monoacetate, a trichothecene. All the trichothecenes proved to be potent inhibitors of O. ramosa seed germination and possess strong zootoxic activity when assayed on Artemia salina brine shrimps. Verrucarin E is inactive on both seed germination and zootoxic assay.  相似文献   

2.
The production of acetylenic phenol metabolites in vitro by three strains of the ascomycete Eutypa lata, the causative agent of dying-arm disease in grapevines, has been investigated. Metabolite composition and yields differed significantly between strains and with growth medium but usually reached a maximum after 24-30 days of fungal growth. A general method for the analysis and identification of metabolites by gas chromatography/mass spectrometry of their trimethylsilyl ether derivatives was developed and individual compounds were quantitated by analytical high-performance liquid chromatography (HPLC) and separated by preparative HPLC. The phenolic aldehyde, eutypine (1), reported to be the grape phytotoxin, occurred in only one of the strains examined whereas the primary metabolite was the corresponding alcohol, eutypinol (2), the presumptive detoxification product. A novel metabolite was isolated as a major constituent, together with a minor component, and their structures were established by spectroscopic methods as a methoxyquinol, named eulatinol (4), and a chromene analog (9) of 2, respectively. The evidence suggests that 1 is not solely responsible for phytotoxicity in grapevines but that dying-arm disease may result from a suite of compounds elaborated by the fungus, with the composition dependent on fungal strain and nutritional source.  相似文献   

3.
Phyllosticta cirsii, a fungal pathogen isolated from diseased Cirsium arvense leaves and evaluated as a biocontrol agent of this noxious perennial weed, produces different phytotoxic metabolites with potential herbicidal activity when grown in liquid cultures. Phyllostictines A-D, four novel oxazatricycloalkenones, were recently isolated from this pathogen and chemically and biologically characterized. Further purification of the same organic extract provided two other metabolites, named phyllostoxin (1) and phyllostin (2), which were characterized by spectroscopic technique (essentially NMR and MS). Phyllostoxin and phyllostin proved to be a new pentasubstituted bicyclo-octatrienyl acetic acid ester and a new pentasubstituted hexahydrobenzodioxine carboxylic acid methyl ester, respectively. When tested on punctured C. arvense leaves, phyllostoxin proved to be highly phytotoxic, causing rapid and large necrosis, whereas phyllostin had no phytotoxicity in this bioassay. This is not surprising, considering the noteworthy structural differences between the two compounds, suggesting the presence of active functional groups in phyllostoxin not present in the other metabolite. These results further support the focused approach of finding novel metabolites with herbicidal properties by looking at the culture extracts of weed fungal pathogens.  相似文献   

4.
Antrodia cinnamomea (formerly A. camphorata) has recently and commercially been used in the formulation of nutraceuticals and functional foods in Taiwan. Because of its diverse properties, the neuroprotective effect was investigated using a fermented A. cinnamomea extract in this study. Serum deprivation-induced apoptosis in neuronal-like pheochromocytoma (PC12) cells was used as a cell stress model, and it was found that A. cinnamomea was effective in preventing serum-deprived apoptosis according to results of an MTT assay and Hoechst staining. Serum deprivation resulted in decreased phosphorylation of extracellular signal-regulated kinase (ERK) and increased phosphorylations of c-Jun NH2-terminal kinase (JNK) and p38, of the family of mitogen-activated protein kinases (MAPKs); however, A. cinnamomea reversed these phenomena, supporting the antagonistic effects between ERK and JNK-p38 in regulating cell survival. The previously identified active component of A. cinnamomea, adenosine (ADO), also exerted the same effects as A. cinnamomea in preventing apoptosis and regulating phosphorylations of MAPKs. Although an inhibitor of the ERK upstream activator blocked A. cinnamomea-induced ERK phosphorylations, it failed to block the protection of A. cinnamomea and ADO. A protein kinase A (PKA) inhibitor blocked the protection by both A. cinnamomea and ADO. Both JNK and p38 inhibitors were effective in preventing the phosphorylations of JNK and p38 and serum deprivation-induced apoptosis. Collectively, A. cinnamomea prevented serum deprivation-induced PC12 cell apoptosis through a PKA-dependent pathway and by suppression of JNK and p38 activities.  相似文献   

5.
Biotransformation of the environmental pollutant 3-methyl-4-nitrophenol (MNP), a newly characterized estrogenic chemical, and the primary breakdown product of the heavily used insecticide fenitrothion was investigated using a common soil fungus. In 96 h, daily culture sacrifice, extraction, and analysis showed that the filamentous fungus, Aspergillus niger VKM F-1119, removed more than 85% of the MNP present in solution (original concentration = 25 mg/L), mostly through biodegradation. Additionally, in 16-day time-course studies, A. niger was capable of biotransformation of MNP at concentrations as high as 70 mg/L. Gas chromatography mass spectroscopy (MS) analyses of culture fluid extracts indicated the formation of four metabolites: 2-methyl-1,4-benzenediol, 4-amino-3-methylphenol, and two singly hydroxylated derivatives of MNP. Culture scale up and metabolite analysis by liquid chromatography MS resulted in the confirmation of the original metabolites plus the detection of an azo derivative metabolite that has not been previously reported before during MNP biodegradation by any micro-organisms.  相似文献   

6.
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7.
Antioxidant properties of Antrodia camphorata in submerged culture   总被引：5，自引：0，他引：5  
The biologically active compounds, antioxidant activities, and free radical scavenging effects of dry matter of cultural medium (DMCM), filtrate (DMF), and different solvent extracts of mycelia from Antrodia camphorata in submerged culture (ACSC) were investigated. DMF showed the strongest inhibition of lipid peroxidation as a function of its concentration, and was comparable to the antioxidant activity of BHA at the same concentration of 0.2 mg/mL. The hexane extract of mycelia had the weakest antioxidant ability, whereas other mycelial extracts exhibited a modest inhibition of lipid peroxidation. DMF and water extract of mycelia (WEM) showed marked activity in free radical scavenging. The antioxidant activities of filtrate and mycelial extracts were correlated with the presence of total polyphenols, the crude triterpenoids, and the protein/polysaccharide ratio of the crude polysaccharides. It was found that DMCM had lower antioxidant ability than DMF in different model systems, indicating that the major antioxidant components in DMF must be derived from the secondary metabolites of mycelia. The results presented herein indicate that DMF could possibly act as a chemopreventing agent with respect to free radical-related diseases.  相似文献   

8.
A dichloromethane extract of root celery yielded falcarinol, falcarindiol, panaxydiol, and the new polyacetylene 8-O-methylfalcarindiol. The structure of the new compound was established by one- and two-dimensional (1D and 2D) NMR, mass spectrometry, and optical rotation data. Nonpolar extracts of roots and bulbs of carrots, celery, fennel, parsley, and parsnip were investigated for their content of polyacetylenes by high-performance liquid chromatography with diode array detection (HPLC-DAD). All five species contained polyacetylenes, although carrots and fennel only in minor amounts. Additionally, the cytotoxicity of the four polyacetylenes against five different cell lines was evaluated by the annexin V-PI assay. Falcarinol proved to be the most active compound with a pronounced toxicity against acute lymphoblastic leukemia cell line CEM-C7H2, with an IC(50) of 3.5 micromol/L. The possible chemopreventive impact of the presented findings is discussed briefly.  相似文献   

9.
Targeted metabolite analysis of aqueous extract of Rumex induratus leaves, in terms of phenolic compounds and organic acids, and the study of its antioxidant activity against the DPPH(*) radical, a reactive oxygen species, hypochlorous acid, and a reactive nitrogen species, nitric oxide ((*)NO), were performed. The samples were collected in several locations, spontaneously occurring or from greenhouse culture, at different stages of development and seasons. The phenolic composition was achieved by high-performance liquid chromatography (HPLC)-diode array detection, and four hydroxycinnamic acid derivatives and 10 flavonoid glycosides (C- and O-heterosides) were determined. Organic acids composition was established by HPLC-UV, revealing five compounds. The total amount of phenolic compounds and organic acids were affected by growing conditions and developmental phase. The aqueous extract exhibited a dose-related activity against all tested reactive species.  相似文献   

10.
Two new triterpene benzoates, 5-dehydrokarounidiol dibenzoate (1) and karounidiol dibenzoate (2), and two new triterpene glycosides, 5alpha,6alpha-epoxymogroside IE(1) (8) and 11-oxomogroside A(1) (9), along with 15 known triterpenoids (one triterpene benzoate, 3; three triterpene mono-ols, 4-6; one triterpene aglycon, 7; and 10 triterpene glycosides, 10-19), were isolated from the ethanol extract of the fruit of Momordica grosvenori. The structures of 1, 2, 8, and 9 were determined on the basis of spectroscopic and chemical methods. Among the known triterpene glycosides, mogroside I E(1) (12) was a new naturally occurring compound. Eighteen triterpenoids (2-19) and 11-oxomogrol (20), a hydrolysis product of 9, were evaluated with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, which is known to be a primary screening test for antitumor promoters. All of the compounds tested showed potent inhibitory effects on EBV-EA induction (70-100% inhibition at 1 x 10(3) mol ratio/TPA).  相似文献   

11.
A method for simultaneous determination of ginsenosides and polyacetylenes in Panax quinquefolium L. (American ginseng) roots was developed. The ginsenosides Rb1, Rb2, Rc, Rd, Re, Rg1, Ro, malonyl-Rb1, malonyl-Rc, and malonyl-Rd and the polyacetylenes falcarinol and panaxydol were extracted from fresh ginseng roots in a sequential extraction process with 100% methanol followed by 80% aqueous methanol and quantified simultaneously in extracts by high-performance liquid chromatography using diode array detection. Separations were achieved with a phosphate buffer-acetonitrile gradient system using an RP-C18 column. Except for Rd, the present extraction method resulted in similar or significantly higher concentrations of both ginsenosides and polyacetylenes in comparison to commonly used extraction methods for these compounds. The contents of polyacetylenes and ginsenosides were determined in the root hairs, lateral roots, and main roots of 6 year old ginseng plants. The total mean concentrations of ginsenosides and polyacetylenes in root hairs were 31.0 g/kg fresh weight (FW) and 2.6 g/kg FW, respectively, whereas the concentrations of these bioactive compounds in the main roots were significantly lower with total mean concentrations of 17.8 g/kg FW for ginsenosides and 0.6 g/kg FW for polyacetylenes. The concentration of individual and total ginsenosides and polyacetylenes did not differ significantly between main roots of different sizes. Consequently, it is possible to do quantitative screening for ginsenosides and polyacetylenes to breed ginseng roots with higher levels of bioactive compounds.  相似文献   

12.
Changes in the physicochemical composition of wine vinegars produced by submerged culture system and aged in wood were followed. Five Sherry wine vinegars and a model vinegar solution were aged in six new American oak butts of 16.6 L capacity. A total of 24 phenolic compounds were monitored during the maturation study (24 months), along with other physicochemical parameters (total extract, acidity, residual alcohol and total phenolic index). Multivariate statistical analysis was applied to the data. From the sixth month on, significant changes were produced in most of the phenolic compounds, mainly aromatic aldehydes and 5-(hydroxymethyl)-2-furaldehyde. When all the phenolic compounds were considered as variables, cluster analysis grouped samples according to the wine substrate employed in the elaboration of vinegars under study. Within each subcluster, samples are arranged according to their aging status when phenolic compounds accounting significative changes at 180 days of aging are considered. Discriminant functions were constructed from the phenolic compounds data set. The validity of these functions was tested using 13 samples of aged commercial Sherry wine vinegars and 25 unaged vinegars. A total of 97.4% of the test samples was correctly classified within its respective group.  相似文献   

13.
殷朝敏  李雨鸿  范秀芝  史德芳  姚芬  程薇  高虹 《核农学报》2022,36(10):1984-1995
为探究不同栽培基质对侧耳属食用菌风味成分的影响以及不同品种食用菌间的风味成分差异,本研究采用顶空固相微萃取结合气相色谱-质谱联用(HS-SPME-GC-MS)技术对桑枝、杂木屑和棉籽壳基质上栽培的6种侧耳属食用菌风味成分进行了分析。结果表明,18个样品中共检出47种挥发性化合物,包括13种醛类化合物、9种醇类化合物、9种酮类化合物、2种呋喃类化合物、2种酯类化合物等。18个样品中的共有成分有17种,包括正己醛、壬醛、1-辛烯-3-醇、3-辛酮、1-辛烯-3-酮、2-正戊基呋喃等。18个样品中挥发性化合物的种类和相对含量差异较大,但棉籽壳基质上栽培的6个菌株子实体中均出现了较高含量的酯类化合物。所有样品中的关键风味成分(ROAV≥1)均包括1-辛烯-3-酮和1-辛烯-3-醇,桑枝基质和杂木屑基质栽培的部分菌株中关键风味成分还包括正己醛、壬醛和2-壬烯醛等。18个样品中总5'-核苷酸含量和总游离氨基酸含量分别为7.86~43.86 mg·g-1 DW和8.54~25.34 mg·g-1 DW, 且杂木屑基质栽培的所有菌株中总游离氨基酸含量均高于桑枝基质和棉籽壳基质。综上所述,棉籽壳基质有利于侧耳属食用菌中酯类化合物的生成,而杂木屑基质有利于游离氨基酸的生成。本研究结果为侧耳属食用菌栽培及风味成分的开发利用提供了科学依据。  相似文献   

14.
Despite the promising antioxidant action of Lamiaceae herbs in vitro, human studies on these potential sources of dietary antioxidants have remained scarce. In this work, the phenolic acids recovered in human urine after single ingestion of Origanum onites extract were analyzed. The excretion was increased 4- and 2-fold during 0-24 and 24-48 h of the follow-up, respectively. The mean increase in the excretion of phenolic compounds exceeded the ingested amount of identified phenolic acids. The result can be partly explained by rosmarinic acid, the main identified phenolic constituent in the extract, as well as flavonoids present in minor amounts, presumably being metabolized into a double amount of simple phenolic metabolites. Furthermore, unidentified phenolic constituents in the extract partly contribute to the excretory increase. The main metabolite, p-hydroxybenzoic acid, was excreted rapidly. The results show that constituents of oregano extract and, in particular, their metabolites may contribute to the dietary intake of phenolic antioxidants.  相似文献   

15.
The metabolites of three species of Apiaceae, also known as Pegaga, were analyzed utilizing (1)H NMR spectroscopy and multivariate data analysis. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) resolved the species, Centella asiatica, Hydrocotyle bonariensis, and Hydrocotyle sibthorpioides, into three clusters. The saponins, asiaticoside and madecassoside, along with chlorogenic acids were the metabolites that contributed most to the separation. Furthermore, the effects of growth-lighting condition to metabolite contents were also investigated. The extracts of C. asiatica grown in full-day light exposure exhibited a stronger radical scavenging activity and contained more triterpenes (asiaticoside and madecassoside), flavonoids, and chlorogenic acids as compared to plants grown in 50% shade. This study established the potential of using a combination of (1)H NMR spectroscopy and multivariate data analyses in differentiating three closely related species and the effects of growth lighting, based on their metabolite contents and identification of the markers contributing to their differences.  相似文献   

16.
Napa Gamay grapes were fermented with four different strains of the yeast Saccharomyces cerevisiae (VL1, MI16, Fermirouge, and RA17). Petite Sirah grapes were fermented with seven different strains of the same yeast (BM45, Fermirouge, RA17, NI, CX3079, A350, and A796). Volatile compounds formed in the wines were analyzed by gas chromatography/mass spectrometry. Volatile compounds found in both wines were alcohols, esters, and acids, as well as some miscellaneous compounds. Isoamyl alcohol was the compound found in the highest relative amount with all four yeast strains in the Napa Gamay wines, followed by 2-phenyl ethanol, monoethyl succinate, and hexanoic acid. The relative amounts of isoamyl alcohol ranged from 30.84% (VL1) to 43.28% (RA17). Major volatile compounds found in Petite Sirah wines were isoamyl alcohol, 2-phenyl ethanol, 2-hydroxy ethyl propanoate, monoethyl succinate, and octanoic acid. The several esters, including 2-hydroxyethyl propanoate, may contribute to the fruity flavor of Petite Sirah wines. Overall, the S. cerevisiae yeast strains used to ferment Napa Gamay grapes and Petite Sirah grapes produced the same major components, with certain variations in formation levels.  相似文献   

17.
During screening of microorganisms producing antifungal metabolites, Streptomyces psammoticus strain KP1404 was isolated. The culture extract of this strain showed potent disease control efficacy against Fusarium wilt on tomato plants. The antifungal metabolites ST-1 and ST-2 were isolated from the culture extract using a variety of chromatographic procedures. On the basis of MS and NMR spectrometric analysis, the structures of the antifungal active compounds ST-1 and ST-2 were determined to be the polyene antibiotics strevertene A and strevertene B, respectively. In vitro, strevertenes A and B showed inhibitory effects against the mycelial growth of Alternaria mali , Aspergillus oryzae , Cylindrocarpon destructans , Colletotrichum orbiculare , Fusarium oxysporum f.sp. lycopersici, and Sclerotinia sclerotiorum , even at concentrations of 4-16 μg/mL. Fusarium wilt development on tomato plants was strongly retarded by treatment with 1 μg/mL of these strevertenes. The disease control efficacies of strevertenes on Fusarium wilt were as remarkable as that of benomyl.  相似文献   

18.
A fungus, Fusarium solani, isolated from the soil, degraded ioxynil (3,5-diiodo-4-hydroxyben-zonitrile) in pure culture into at least eight products. Five products were detected in the organic fractions extracted from a culture grown in [14C]cyano-labeled ioxynil. Three additional products were separated by ion-exchange chromatography of the acidified aqueous phase. Cultures grown in the presence of [14C]ring-labeled ioxynil produced the same products in the organic extract and four to five products in the aqueous phase. The cyano-carbon of ioxynil was released as CO2 at a faster rate than that of ring-carbons and was released after the initial ring cleavage. Two of the metabolites were identified as 3,5-diiodo-4-hydroxybenzamide and 3,5-diiodo-4-hydroxybenzoic acid.  相似文献   

19.
Four trichothecene-producing strains of Fusarium graminearum were grown on three maize grain fractions, whole grain, degermed grain, and the germ, to determine the effect of natural substrates on mycotoxin production. Monitoring the ergosterol content after 25 days of incubation indicated that fungal growth on all grain fractions was comparable. Trichothecene (TCT) production was highest on degermed grain, less on whole grain, and very low or nondetectable on the germ; similar results were found with four different strains. It was concluded that inhibitor(s) of TCT biosynthesis were present in maize germ. The presence of phenolic compounds was investigated in the different fractions. The hydroxamate 4-acetylbenzoxazolin-2-one (4-ABOA), a known inhibitor of mycotoxin production, was found in the degermed and whole grain fractions but not in the germ. Therefore, the TCT inhibition observed on the maize germ fraction used in our study is clearly not linked to 4-ABOA. Other soluble phenolic compounds were found at a much higher concentration in the germ than in the two other fractions. The inhibition property of the soluble ester-bound extracts was tested in liquid culture. A possible role for these compounds is discussed.  相似文献   

20.
A gas chromatography-mass spectrometry approach was employed to evaluate the use of metabolite patterns to differentiate fruit from six commercially grown apple cultivars harvested in 2008. Principal component analysis (PCA) of apple fruit peel and flesh data indicated that individual cultivar replicates clustered together and were separated from all other cultivar samples. An independent metabolomics investigation with fruit harvested in 2003 confirmed the separate clustering of fruit from different cultivars. Further evidence for cultivar separation was obtained using a hierarchical clustering analysis. An evaluation of PCA component loadings revealed specific metabolite classes that contributed the most to each principal component, whereas a correlation analysis demonstrated that specific metabolites correlate directly with quality traits such as antioxidant activity, total phenolics, and total anthocyanins, which are important parameters in the selection of breeding germplasm. These data sets lay the foundation for elucidating the metabolic basis of commercially important fruit quality traits.  相似文献   

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