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1.
Nitric oxide (NO) has been evidenced to mediate biosynthesis of polyphenols in Inonotus obliquus. However, it remains unknown how NO regulates their biosynthesis. Here we show that higher cellular NO levels coincided with
higher accumulation of S-nitrosothiols (SNO; the products of NO combined with a specific residue in glutathione or proteins) and polyphenols, and
higher activity of denitrosylated S-nitrosoglutathione reductase (GSNOR) and thioredoxin reductase (TrxR). This homeostasis was breached by GSNOR or TrxR inhibitors.
Inhibiting GSNOR boosted TrxR activity, but reduced SNO formation, coinciding with an enhanced production of polyphenols.
Likewise, inhibiting TrxR increased GSNOR activity and SNO production, but downregulated accumulation of polyphenols. Inhibiting
GSNOR or TrxR also modified the polyphenolic profiles of I. obliquus. Suppressing GSNOR-enhanced biosynthesis of phelligridins C and H, inoscavin C and methyl inoscavin B, but reduced that of
phelligridin D, methyl inoscavin A, davallialactone and methyl davallialactone, the typical polyphenols in I. obliquus. Similarly, downregulating TrxR increased production of phelligridin D, methyl inoscavin A, davallialactone, and methyl davallialactone,
but shrinking that of phelligridins C and H, methyl inoscavin B and inoscavin C. Thus, in I. obliquus, the state of S-nitrosylation and denitrosylation affects not only the accumulation of polyphenols, but also their metabolic profiles. 相似文献
2.
Li Zheng Xiaojun Yan Jilin Xu Haimin Chen Wei Lin 《Applied Biochemistry and Microbiology》2005,41(1):29-33
Among marine bacteria isolated from the cytotoxic sponge Hymeniacidon perleve, one strain NJ6-3-1 classified as Pseudomonas sp. showed both cytotoxic and antimicrobial activities. Fatty acid analysis indicated that the bacterial strain consists mainly of C16:1, C16:0, C18:1, C18:0, C15:0, C14:0. One unusual 9,10-cyclopropane-C17:0 fatty acid and C26:0 also constitute major components, as well as the existence of squalene, the precursor of triterpenoids. The major metabolites in the culture broth were identified as alkaloids, including diketopiperazines and indole compounds, namely 3,6-diisopropylpiperazine-2,5-dione, 3-benzyl-3-isopropylpiperazine-2,5-dione, 3,6-bis-(2-methylpropyl)-piperazine-2,5-dione, indole-3-carboxaldehyde, indole-3-carboxylic acid methyl ester, indole-3-ethanol, and quinazoline-2,4-dione.From Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 1, 2005, pp. 35–39.Original English Text Copyright © 2005 by Li Zheng, Xiaojun Yan, Jilin Xu, Haimin Chen, Wei Lin.This article was submitted by the authors in English. 相似文献
3.
Allelopathic effects of the submerged macrophyte Potamogeton malaianus on Scenedesmus obliquus were assessed using a two-phase approach under controlled laboratory conditions. In the co-culture experiment (phase І),
the growth of S. obliquus at two different initial cell densities was significantly inhibited by P. malaianus. Moreover, the growth inhibition was dependent on the biomass density of P. malaianus. Antioxidant enzymes (SOD, CAT and POD), MDA, APA, total soluble protein, protein electrophoretic pattern and morphology
of S. obliquus were determined after the co-culture experiment was terminated. The activities of SOD, CAT, POD and APA at the low initial
cell density were stimulated, the contents of MDA and total soluble protein were increased, and some special protein bands
disappeared in P. malaianus treatments. The macrophyte had no effect on the activities of SOD and APA at the high initial cell density, but significantly
influenced other physiological parameters of S. obliquus with the increase of biomass density. The morphology of S. obliquus showed no difference in the macrophyte treatments and the controls, and the cultures were dominated by 4-celled coenobia.
The results indicated P. malaianus had significant allelopathic effects on the growth and physiological processes of S. obliquus. Moreover, the allelopathic effects depended on initial algal cell density, biomass density of the macrophyte, and their
interaction. In the experiment of P. malaianus culture filtrates (phase II), filtrates from combined culture of plant and S. obliquus at the low initial cell density exhibited no apparent growth inhibitory effect on S. obliquus. The result showed that initial addition of growth-inhibiting plant filtrates had no allelopathic effect on S. obliquus. We concluded that the allelopathic effects on S. obliquus were found in the presence of P. malaianus, but not in P. malaianus filtrates. However, the absence of allelopathic effect on S. obliquus might be due to the very low concentrations of allelochemicals in the filtrates.
Handling editor: S. M. Thomas 相似文献
4.
The balloon flower (Platycodon grandiflorum) is a popular traditional medicinal plant used in Korea to treat conditions such as bronchitis, asthma, tuberculosis, diabetes,
and inflammatory diseases. Recently, immunopharmacological research identified triterpenoid and saponin as important active
compounds in P. grandiflorum. To study and extract these compounds and other metabolites from P. grandiflorum, a technique was developed for producing hairy root cultures, which are a reliable source of plant compounds. To achieve this,
the activity of Agrobacterium rhizogenes was exploited, which can transfer DNA segments into plant genomes after infecting them. In this study, the A. rhizogenes strain R1000 was determined that had the highest infection frequency (87.5%) and induced the most hairy roots per plant,
and the concentration of antibiotics (75 mg/l kanamycin) was elucidated for selection after transformation. Wild-type and
transgenic hairy roots contained various phenolic compounds, although both of them had similar concentrations of phenolic
compounds. In the future, the protocols described here should be useful for studying and extracting valuable metabolites such
as phenolic compounds from P. grandiflorum hairy root cultures. 相似文献
5.
采用基于核磁共振代谢组学的方法研究了两株地理隔离的桦褐孔菌中国牡丹江菌株(IOM)和芬兰万塔菌株(IOV)在深层培养过程中主要代谢产物组成的差异。IOM和IOV两菌株在培养过程中积累菌丝体生物量、菌丝体酚类(TMP)以及三萜化合物(TMT)的过程相似,但IOM菌株产生较高水平的TMP。代谢产物组成动力学比较结果表明,IOM在第3天含有较高水平的硬毛素类似物、桦褐孔菌二糖和TMT,但在第5天均有所下降。导致这些差异的代谢产物为fuscoparianolD,21,24-羊毛甾-7,9(11),23-三烯-3β,22,25-三醇,羊毛甾-8,23-二烯-3β,22,25-三醇,23,24-环戊羊毛甾-3β,21,25-三醇-8-烯,桦褐孔菌二糖,phelligridinsC,D及H,甲基地花菌素A和C,地花菌素B,davallialactone及methyl davallialactone。这些代谢产物在IOV的提取物中均参与清除自由基,而在IOM的提取物中主要是酚类化合物参与自由基的清除。两菌株的这些差异反应了环境条件对桦褐孔菌生长及代谢的影响,即不仅影响其次生代谢产物的合成,还影响代谢产物在防止细胞氧化损伤过程中所起的作用。 相似文献
6.
Huizhong Chen Haiyan Xu Thomas M. Heinze Carl E. Cerniglia 《Journal of industrial microbiology & biotechnology》2009,36(12):1459-1466
The capability of Lactobacillus acidophilus and Lactobacillus fermentum to degrade azo dyes was investigated. The bacteria were incubated under anaerobic conditions in the presence of 6 μg/ml Methyl
Red, Ponceau BS, Orange G, Amaranth, Orange II, and Direct Blue 15; 5 μg/ml Sudan I and II; or 1.5 μg/ml Sudan III and IV
in deMann–Rogosa–Sharpe broth at 37°C for 36 h, and reduction of the dyes was monitored. Both bacteria were capable of degrading
all of the water-soluble azo dyes to some extent. They were also able to completely reduce the oil-soluble diazo dyes Sudan
III and IV but were unable to reduce the oil-soluble monoazo dyes Sudan I and II to any significant degree in the concentrations
studied. Growth of the bacteria was not significantly affected by the presence of the Sudan azo dyes. Metabolites of the bacterial
degradation of Sudan III and IV were isolated and identified by liquid chromatography electrospray ionization tandem mass
spectrometry analyses and compared with authentic standards. Aniline and o-toluidine (2-methylaniline), both potentially carcinogenic aromatic amines, were metabolites of Sudan III and IV, respectively. 相似文献
7.
An experiment was carried out to evaluate the effects of phosphorus concentration (1, 4 and 10 mg l−1) and temperature (15 and 25°C) on chlorophyll a (chl a) contents and cell size/volume of green alga Scenedesmus
obliquus and blue green alga Microcystis aeruginosa. Long-term field data from Lake Taihu, a large, shallow eutrophic lake between Jiangsu and Zhejiang Provinces, China, was
also used to evaluate the effect of temperature on the model between chl a and total phosphorus (TP). The chl a content of both algae increased with an increase in phosphorus concentration and temperature. Temperatures showed a significantly
different effect on chl a content of S. obliquus at a phosphorus concentration of 10 mg l−1, whereas there was no significant difference at the two lower phosphorus levels. For M. aeruginosa, temperatures presented significantly different effects on the chl a contents at three phosphorus concentrations. Chl a content of neither alga presented an interaction between the nutrient and the temperature. Long-term field data from Lake
Taihu also indicated that the addition of temperature to the model increased predictability of chl a by TP. The length/diameter and volume of both algae were greater at the lower temperature and phosphorus concentration. Moderate
negative correlations were observed between algal size, volume, and chl a content. Our results suggest that phosphorus concentration and temperature could change chl a contents and size in species-specific algal cells and that temperature should be considered when building the model of TP
and chl a concentration. 相似文献
8.
Hui Chen Mingchao Yan Jinwei Zhu Xiangqun Xu 《Journal of industrial microbiology & biotechnology》2011,38(2):291-298
We reported that lignocellulose decomposition can be used to facilitate the production of bioactive polysaccharides from submerged
culture of Inonotus obliquus. Exo-polysaccharide (EPS) production and antioxidant activity by Inonotus obliquus was enhanced by employing lignocellulose decomposition in a corn straw-containing submerged fermentation. A significant increase
in the EPS production and hydroxyl radical scavenging activity from 1.09 ± 0.01 g/l and 72.3 ± 1.9% in a basal medium to 1.38 ± 0.02 g/l
and 82.7 ± 0.5% in a corn straw-containing medium was obtained. A synchronized effect between lignocellulose decomposition
and malondialdehyde presenting hydroxyl radical concentration in the fermentation broth was identified. The adding of thiourea,
a hydroxyl radical-scavenging reagent, suppressed malondialdehyde generation and lowered the lignocellulose decomposition
rate. Correspondingly, the EPS production and hydroxyl radical scavenging activity decreased to 1.26 g/l and 74%. The EPS
obtained from the corn straw-containing medium also presented the strongest superoxide radical scavenging activity. The monosaccharide
components of the EPS from the corn straw-containing medium are rhamnose, arabinose, xylose, mannose, glucose, and galactose
with molar proportions at 3.0, 3.0, 0.9, 46.6, 11.4, and 35.1%, respectively, which are largely different from the molar proportions
of the EPS from the basal medium. 相似文献
9.
Laboratory experiments were conducted to elucidate the allelopathic effects of exudates from the aquatic macrophyte Stratiotes aloides on the growth and morphology of the green alga Scenedesmus obliquus. Both water originating from a S. aloides culture and water that had not been in contact with S. aloides was simultaneously inoculated with S. obliquus cells. In all experiments we observed a highly significant inhibitory effect of Stratiotes water on the green alga. The duration of the lag phase as well as the initial biovolume doubling time of S. obliquus were extended. The growth rate of S. obliquus was only significantly inhibited by the younger Stratiotes plants. Furthermore, the mean particle volume (MPV) of Scenedesmus increased significantly in the presence of Stratiotes water in all three experiments. Microscopic analyses confirmed that S. obliquus forms more colonies in the presence of water from a S. aloides culture. Colonies of phytoplankton have higher sinking rates than single phytoplankton cells of the same species and disappear faster from the upper water layers, reducing the competition for light between algae and macrophytes. 相似文献
10.
María del Pilar Nicasio-Torres Juan Carlos Erazo-Gómez Francisco Cruz-Sosa 《Acta Physiologiae Plantarum》2009,31(5):905-914
Two Cecropia species (Cecropia obtusifolia and C. peltata), known as guarumbo, are employed in Mexican traditional medicine to treat diabetes mellitus; the leaves of both species contain phenolic bioactive
compounds such as chlorogenic acid (CA) and isoorientine (ISO), which have been attributed with hypoglycemic, hypolipidemic,
and antioxidant properties. An in vitro propagation protocol was developed from existing apical bud meristem from C. obtusifolia seedlings; the shoot generation was induced on Murashige and Skoog (MS) medium supplemented with varying concentrations of
6-benzylaminopurine and kinetin (Kn) combined with either α-naphtalene acetic acid (NAA) or indole-3-acetic acid (IAA) auxins.
Best morphogenetic response was developed with Kn 26.64 μM combined with either NAA or IAA 0.57 μM, respectively; likewise,
C. peltata-seedling apical buds were subjected to these best selected treatments. Cecropia obtusifolia and C. peltata shoots were rooted in growth regulator-free half-strength MS medium, and regenerated whole plants were adapted successfully
under greenhouse conditions and field. Leaves from both Cecropia-micropropagated plants produced the phenolic compounds CA and ISO, with highest concentrations in leaves from 18-month C. obtusifolia (12.28 ± 7.06 mg g−1 dry leaves of CA and 8.30 ± 2.70 mg g−1 dry leaves of ISO) growth in the field. Our results offer a protocol of apical-bud use for multiplication and curative-property
conservation of the two previously mentioned important Mexican medicinal plants. 相似文献
11.
12.
Various solvent extracts of the lichen Usnea ghattensis showed good antioxidant activity. A methanol extract prevented lipid peroxidation by 87% followed by 65% in Trolox at 20 μg/ml. It also showed superoxide anion scavenging activity and free radical scavenging activity 56% and 73%, respectively. The known antioxidants butylated hydroxytoluene (BHT), butylated hydroxyanisol (BHA) and quercetin at similar concentrations showed superoxide anion scavenging activity of 68, 59 and 47% and free radical scavenging activity 83, 77 and 69%, respectively. In addition, these extracts were inhibitory against Bacillus licheniformis, Bacillus megaterium, Bacillus subtilis and Staphylococcus aureus with MIC values of 5–10 μg/ml.Received after revisions 10 May 2005 相似文献
13.
P. Selvakumar S. Rajasekar K. Periasamy N. Raaman 《World journal of microbiology & biotechnology》2008,24(10):2125-2131
Melanins are enigmatic pigments that are produced by a wide variety of microorganisms including several species of bacteria
and fungi. For more than 40 years, fungi have been known to produce pigments called melanins. Melanin pigment production by
mushrooms was not intensively studied. The present study was carried out on isolation and characterization of melanin from
an edible mushroom Pleurotus
cystidiosus var. formosensis. The mushroom produced dark mucous mass of hyaline arthrospores on mycelium. The coremia exclusively produced dikaryotic
arthrospores with the remnant of a clamp connection. Continuous cell extension and division in the coremium stipe supplied
cells for arthroconidiation at the coremium apex, which is surrounded by a liquid droplet (coremioliquid). The black coloured
coremea (conidia) were produced by Antromycopsis macrocarpa (anamorph of P. cystidiosus) when cultured on potato dextrose agar medium. The agar plate was incubated at continuous light illumination for high amount
of pigment (coremea) production. The slimy layer of the coremea was extracted and partially purified by alkaline and acid
treatment. The black pigment was confirmed as melanin based on UV, IR and EPR spectra apart from chemical analysis. This is
the first report on characterization of melanin obtained from Pleurotus
cystidiosus var. formosensis. 相似文献
14.
Tropilaelaps
mercedesae is a serious ectoparasite of Apis
mellifera in China. The aim of this study was to investigate the infestation rates and intensity of T. mercedesae in A. mellifera in China, and to explore the relative importance of climate, district, management practices and beekeeper characteristics
that are assumed to be associated with the intensity of T. mercedesae. Of the 410 participating apiaries, 379 apiaries were included in analyses of seasonal infestation rates and 352 apiaries
were included in multivariable regression analysis. The highest infestation rate (86.3%) of T. mercedesae was encountered in autumn, followed by summer (66.5%), spring (17.2%) and winter (14.8%). In autumn, 28.9% (93) of the infested
apiaries were in the north (including the northeast and northwest of China), 71.1% (229) were in the central and south (including
east, southeast and southwest China), and 306 apiaries (82.9%) were co-infested by both T. mercedesae and Varroa. Multivariable regression analysis showed that geographical location, season, royal jelly collection and Varroa infestation were the factors that influence the intensity of T. mercedesae. The influence of beekeeper’s education, time of beekeeping, operation size, and hive migration on the intensity of T. mercedesa was not statistically significant. This study provided information about the establishment of the linkage of the environment
and the parasite and could lead to better timing and methods of control. 相似文献
15.
Ruixiang Zhao Junliang Sun Haizhen Mo Yang Zhu 《World journal of microbiology & biotechnology》2007,23(2):195-200
Metabolites from Lactobacillus acidophilus were analysed. The results showed that Lactobacillus
acidophilus Ind-1 and Lactobacillus acidophilus Lakcid produced respectively 12.73 g and 13.33 g lactic acid l−1 after incubating in skim milk at 37 °C for 36 h; and 2.229 unit and 1.808 unit β-galactosidase l−1 in an MRS medium. The proteolytic activity of Lactobacillus acidophilus was high and the content of 17 free amino acids in the fermented milk of Lactobacillus
acidophilus Ind-1 and Lactobacillus acidophilus Lakcid was 394.4 mg l−1 and 563.2 mg l−1, respectively. Meantime, Lactobacillus acidophilus reduced cholesterol level in an MRS medium supplemented with cholesterol. Furthermore, Lactobacillus
acidophilus Ind-1 and Lactobacillus acidophilus Lakcid showed antimicrobial activity against Bacillus anthracis and Escherichia coli. 相似文献
16.
In this study, an aqueous extract of leaves from Melothria maderaspatana was tested for in vitro antioxidant activity. Free radical scavenging assays, such as hydroxyl radical, hydrogen peroxide, superoxide anion radical
and 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2’-azinobis-(3-ethyl-enzothiazoline-6-sulfonic acid) (ABTS) radical scavenging,
and reducing power assay, were studied. The extract effectively scavenged hydroxyl radical, hydrogen peroxide and superoxide
anion radicals. It also scavenged DPPH and ABTS radicals. Furthermore, it was found to have reducing power. All concentrations
of leaf extract exhibited free radical scavenging and antioxidant power, and the preventive effects were in a dose-dependent
manner. The antioxidant activities of the above were compared to standard antioxidants such as butylated hydroxytoluene (BHT),
ascorbic acid, and α-tocopherol. The results obtained in the present study indicate that the M. maderaspatana extract could be considered a potential source of natural antioxidant. 相似文献
17.
Pseudomonas putida and Pseudomonas fluorescens present as a coculture were studied for their abilities to degrade benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX) under various growth conditions. The coculture effectively degraded various concentrations of BTEX as sole carbon sources. However, all BTEX compounds showed substrate inhibition to the bacteria, in terms of specific growth, degradation rate, and cell net yield. Cell growth was completely inhibited at 500mgl–1 of benzene, 600mgl–1 of o-xylene, and 1000mgl–1 of toluene. Without aeration, aerobic biodegradation of BTEX required additional oxygen provided as hydrogen peroxide in the medium. Under hypoxic conditions, however, nitrate could be used as an alternative electron acceptor for BTEX biodegradation when oxygen was limited and denitrification took place in the culture. The carbon mass balance study confirmed that benzene and toluene were completely mineralized to CO2 and H2O without producing any identifiable intermediate metabolites. 相似文献
18.
Marinella De Leo Luigi Milella Alessandra Braca Nunziatina De Tommasi 《Phytochemistry Reviews》2018,17(4):751-783
Cedrela P. Browne is a genus of trees, strictly related to Toona, in the Meliaceae, a family of flowering plants in the order Sapindales, which is among the most diverse sources of secondary metabolites in the Angiospermae. The most abundant metabolites in these genera are limonoids, tetranortriterpenes possessing diverse structural features, apotirucallanes, tirucallanes, and other triterpenes. The chemical constituents isolated from the genera Cedrela and Toona over the past decades, together with their biological activities, have been compiled in this article. The allelochemical and the phytotoxic activity of limonoids and triterpenoids seem to play a crucial role in the ecological function of these metabolites. While, the most promising use in human field seems related to their antimalarial and anti-inflammatory effects, even that further investigation are still needed. 相似文献
19.
Cristina M. Monteiro Susana C. Fonseca Paula M. L. Castro F. Xavier Malcata 《Journal of applied phycology》2011,23(1):97-103
Aquatic environments often contain toxic heavy metals that may enter the food web via uptake by microalgae and eventually
cause severe poisoning problems at higher trophic levels. The effects of Cd and Zn cations upon growth of two native green
microalgal species, Scenedesmus obliquus and Desmodesmus pleiomorphus (previously isolated from a polluted site in Northern Portugal), were accordingly evaluated. Growth inhibition of the microalgal
cells was determined following exposure for 96 h to several initial concentrations of aqueous solutions of either of those
two metals. At the higher end of Cd and Zn experimental concentration ranges, a significant reduction in cell density was
observed in the cultures; EC50 values, calculated after fitting a Weibull model to the experimental data, were 0.058 and 1.92 mg L−1 for Cd and 16.99 and 4.87 mg L−1 for Zn in the case of S. obliquus and D. pleiomorphus, respectively. One observed that S. obliquus can tolerate higher Zn concentrations than D. pleiomorphus, but the reverse holds regarding exposure to Cd. 相似文献
20.
An SJ Pandeya D Park SW Li J Kwon JK Koeda S Hosokawa M Paek NC Choi D Kang BC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(3):459-470
A temperature-sensitive mutant of Capsicum chinense, sy-2, shows a normal developmental phenotype when grown above 24°C. However, when grown at 20°C, sy-2 exhibits developmental defects, such as chlorophyll deficiency and shrunken leaves. To understand the underlying mechanism
of this temperature-dependent response, phenotypic characterization and genetic analysis were performed. The results revealed
abnormal chloroplast structures and cell collapse in leaves of the sy-2 plants grown at 20°C. Moreover, an excessive accumulation of reactive oxygen species (ROS) resulting in cell death was detected
in the chlorophyll-deficient sectors of the leaves. However, the expression profile of the ROS scavenging genes did not alter
in sy-2 plants grown at 20°C. A further analysis of fatty acid content in the leaves showed the impaired pathway of linoleic acid
(18:2) to linolenic acid (18:3). Additionally, the Cafad7 gene was downregulated in sy-2 plants. This change may lead to dramatic physiological disorder and alteration of leaf morphology in sy-2 plants by losing low-temperature tolerance. Genetic analysis of an F2 population from a cross between C. chinense ‘sy-2’ and wild-type C. chinense ‘No. 3341’ showed that the sy-2 phenotype is controlled by a single recessive gene. Molecular mapping revealed that the sy-2 gene is located at a genomic region of the pepper linkage group 1, corresponding to the 300 kb region of the Ch1_scaffold
00106 in tomato chromosome 1. Candidate genes in this region will reveal the identity of sy-2 and the underlying mechanism of the temperature-dependent plant response. 相似文献