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1.
This study aimed to evaluate the antioxidant activities of a cultured medicinal fungus—Armillariella mellea (Vahl. ex Fr.) Karst. (AM). Three antioxidant assay systems, namely cytochrome c, xanthine oxidase inhibition, and FeCl2-ascorbic acid stimulated lipid peroxidation in rat tissue homogenate tests, were used. Total flavonoid and phenol contents
of AM extracts were also analyzed. Results showed that both aqueous (AM-H2O) and ethanolic (AM-EtOH) extracts of solid state cultured AM showed antioxidant activities in a concentration-dependent
manner. At concentrations 1–100 μg/ml, the free radical scavenging activity was 73.7–92.1% for AM-H2O, and 60.0–90.8% for AM-EtOH. These extracts also showed an inhibitory effect on xanthine oxidase activity, but with a lesser
potency (IC50 is 9.17 μg/ml for AM-H2O and 7.48 μg/ml for AM-EtOH). In general, AM-H2O showed a stronger antilipid peroxidation activity on different rat’s tissues than AM-EtOH. However, both AM extracts displayed
a weak inhibitory effect on lipid peroxidation in plasma. Interestingly, the antilipid peroxidation activity of AM-H2O (IC50–6.66 μg/ml) in brain homogenate was as good as IC50–5.42 μg/ml. AM-H2O (80.0 mg/g) possessed a significantly higher concentration of total flavonoids than AM-EtOH (30.0 mg/g), whereas no difference
was noted in the total phenol content between these two extracts. These results conclude that AM extracts possess potent free
radical scavenging and antilipid peroxidation activities, especially the AM-H2O in the brain homogenate.
Published in Russian in Prikladnaya Biokhimiya i Mikrobiologiya, 2007, Vol. 43, No. 4, pp. 495–500.
The text was submitted by the authors in English. 相似文献
2.
Bimal Kumar Ghimire Eun Soo Seong Eun Jung Goh Eun Young Kang Joung Kuk Ahn Chang Yeon Yu Ill Min Chung 《Plant Growth Regulation》2011,63(1):1-6
Codonopsis lanceolata Trautv (Companulaceae) is a folk medicine in Korea. To shift the content of tocopherol and enhance its antioxidant properties,
we overexpressed the γ-tocopherol methyltransferase (γ-tmt) gene in C. lanceolata. The antioxidant activity of methanolic crude extracts of the transgenic plants was compared to that of control plants using
the 1,1-diphenyl-2-picrylhydrazyl radical scavenging method, with α-tocopherol and butylated hydroxy toluene as standard antioxidants.
The antioxidant activity of the leaf and root extracts of transgenic plants was higher (IC 50 12–17.33 and 408–524 μg/ml, respectively) than that of control plant leaf and root extracts (18 and 529 μg/ml, respectively).
High-performance liquid chromatography analysis of phenolic compounds confirmed an increase in the levels of 12 major phenolic
acids and flavonoids in the leaf and root extracts of transgenic plants compared to control plants. We also found that the
rate of photosynthesis was 48% higher in transgenic plants than in control plants. Based on these results, we suggest that
increases in the α-tocopherol level in transgenic C. lanceolata plants may result in increases in the photosynthetic performance and antioxidant metabolism of these plants. 相似文献
3.
Extracts fromshiitake (Lentinula edodes) mycelial culture broth, by an organic solvent ethyl acetate, inhibited the proliferation of cultured cells. At lower concentrations
(1.25–15 μg/ml), this inhibition, measured by the MTT assay, was dose- and cell line-dependent. Inhibition of tumor cells,
such as Caski, SiHa, HeLa, HP-1 and A375, byL. edodes-436 extracts was stronger than inhibition of normal cells (3T3). At 20 μg/ml, the extracts induced changes in cell shape,
DNA-fragmentation and the activation of caspase-3. The extracts also inhibited the binding of E2F protein to its promoter.
The results suggest that extracts ofL. edodes culture broth contain substances that have the ability to induce apoptosis in the cultured cells. 相似文献
4.
Dae Haeng Cho Yun Jie Lee Youngsoon Um Byoung-In Sang Yong Hwan Kim 《Applied microbiology and biotechnology》2009,83(6):1035-1043
In the present study, we investigated the peroxidase-catalyzed detoxification of model phenolic compounds and evaluated the
inhibitory effects of the detoxified solution on butanol production by Clostridium beijerinckii National Collection of Industrial and Marine Bacteria Ltd. 8052. The six phenolic compounds, p-coumaric acid, ferulic acid, 4-hydroxybenzoic acid, vanillic acid, syringaldehyde, and vanillin, were selected as model fermentation
inhibitors generated during pretreatment and hydrolysis of lignocellulose. The enzyme reaction was optimized as a function
of the reaction conditions of pH, peroxidase concentration, and hydrogen peroxide to substrate ratio. Most of the tested phenolics
have a broad optimum pH range of 6.0 to 9. Removal efficiency increased with the molar ratio of H2O2 to each compound up to 0.5–1.25. In the case of p-coumaric acid, ferulic acid, vanillic acid, and vanillin, the removal efficiency was almost 100% with only 0.01 μM of enzyme.
The tested phenolic compounds (1 g/L) inhibited cell growth by 64–74%, while completely inhibiting the production of butanol. Although syringaldehyde and vanillin were less toxic on cell growth, the level of inhibition on the butanol production was
quite different. The detoxified solution remarkably improved cell growth and surprisingly increased butanol production to
the level of the control. Hence, our present study, using peroxidase for the removal of model phenolic compounds, could be
applied towards the detoxification of lignocellulosic hydrolysates for butanol fermentation. 相似文献
5.
Ilkay Orhan Berrin Özçelik Sinem Aslan Murat Kartal Taner Karaoglu Bilge Şener Salih Terzioglu M. Iqbal Choudhary 《Phytochemistry Reviews》2007,6(1):189-196
Purpose of the present study was to evaluate antioxidant, antibacterial, antifungal, and antiviral activities of the petroleum
ether, chloroform, ethyl acetate and methanol extracts as well as the alkaloid fraction of Lycopodium clavatum L. (LC) from Lycopodiaceae growing in Turkey. Antioxidant activity of the LC extracts was evaluated by 1,1-diphenyl-2-picrylhydrazyl
(DPPH) radical-scavenging method at 0.2 mg/ml using microplate-reader assay. Antiviral assessment of LC extracts was evaluated
towards the DNA virus Herpes simplex (HSV) and the RNA virus Parainfluenza (PI-3) using Madin-Darby Bovine Kidney (MDBK) and Vero cell lines. Antibacterial and antifungal activities of the extracts
were tested against standard and isolated strains of the following bacteria; Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Acinobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis as well as the fungi; Candida albicans and C. parapsilosis. All of the extracts possessed noteworthy activity against ATCC strain of S. aureus (4 μg/ml), while the LC extracts showed reasonable antifungal effect. On the other hand, we found that only the chloroform
extract was active against HSV (16–8 μg/ml), while petroleum ether and alkaloid extracts inhibited potently PI-3 (16–4 μg/ml
and 32–4 μg/ml, respectively). However, all of the extracts had insignificant antiradical effect on DPPH. In addition, we
also analyzed the content of the alkaloid fraction of the plant by capillary gas chromatography-mass spectrometry (GC-MS)
and identified lycopodine as the major alkaloid. 相似文献
6.
Neda S. Lakić Neda M. Mimica-Dukić Jelena M. Isak Biljana N. Božin 《Central European Journal of Biology》2010,5(3):331-337
The antioxidant properties of methanol extracts of Lady’s Bedstraw (Galium verum L., Rubiaceae) herb from two different localities in Serbia were evaluated. Antioxidant activity was assessed in four different
model systems. Free radical scavenging capacity (RSC) was examined by measuring the scavenging activity of extracts on 2,2-diphenyl-1-pycrylhydrazil
(DPPH) and hydroxyl radical (OH), as well as on hydrogen peroxide. In addition, the protective effects of lipid peroxidation
(LP) in corn oil were evaluated by the TBA-assay using the Fe2+/ascorbate system of induction. The amount of dried extract, the content of total phenolics, flavonoids and chlorophylls was
also determined. Extracts from both locations expressed very strong scavenger activity, reducing the DPPH⊙ (IC50=3.10 μg/mland 8.04 μg/ml) and OH radical formation (IC50=0.05 μg/ml and 0.54 μg/ml) and neutralising H2O2 (IC50=4.98 μg/ml and 3.80 μg/ml), in a dose dependant manner. Also, examined extracts showed notable inhibition of LP (IC50=11.69 μg/ml and 19.47 μg/ml). The observed differences in antioxidant activity could be partially explained by the levels
of phenolics (2.44–4.65 mg and 4.57–5.16 mg gallic acid equivalents/g dry extract), flavonoids (6.38–10.70 μg and 15.56–17.96
μg quercetin equivalents/g dry extract) and chlorophylls in the investigated Lady’s Bedstraw extracts. 相似文献
7.
Wiyakrutta Suthep Sriubolmas Nongluksna Panphut Wattana Thongon Nuntawan Danwisetkanjana Kannawat Ruangrungsi Nijsiri Meevootisom Vithaya 《World journal of microbiology & biotechnology》2004,20(3):265-272
A total of 81 Thai medicinal plant species collected from forests in four geographical regions of Thailand were examined for
the presence of endophytic fungi with biological activity. Of 582 pure isolates obtained, 360 morphologically distinct fungi
were selected for cultivation on malt Czapek broth and yeast extract sucrose broth, from which extracts were tested for biological
activity. Extracts of 92 isolates could inhibit Mycobacterium tuberculosis (MIC 0.0625–200 μg ml−1) when tested by the microplate Alamar blue assay, while extracts of six inhibited Plasmodium falciparum (IC50 of 1.2–9.1 μg ml−1) as determined by the [3H]hypoxanthine incorporation method. Strong anti-viral activity against Herpes simplex virus type 1 was observed in 40 isolates
(IC50 of 0.28–50 μg ml−1). The sulphorhodamine B assay for activity against cancer cell lines revealed that 60 were active against human oral epidermoid
carcinoma cells (EC50 0.42–20 μg ml−1) and 48 against breast cancer cells (EC50 0.18–20 μg ml−1). Bioactivity profile was affected by the type of culture medium. Given the high incidence of bioactive extracts and the
fact that most of the isolated fungi could not be identified due to lack of spore formation, the results suggested that Thai
medicinal plants can provide a wide variety of endophytes that might be a potential source of novel bioactive compounds.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
Alma R. López-Laredo Fanny D. Ramírez-Flores Gabriela Sepúlveda-Jiménez Gabriela Trejo-Tapia 《In vitro cellular & developmental biology. Plant》2009,45(5):550-558
Tecoma stans is a tropical plant from the Americas. Antioxidant activity and both phenolic compound and flavonoid total content were determined
for callus tissue of T. stans cultured in either a set photoperiod or in darkness. Callus lines from three explant types (hypocotyls, stem, and leaf) were
established on B5 culture medium supplemented with 0.5 μM 2,4-D and 5.0 μM kinetin. While leaf-derived callus grew slower
under a 16-h photoperiod (specific growth rate, μ = 0.179 d−1, t
D = 3.9 d) than in darkness (μ = 0.236 d−1, t
D = 2.9 d), it accumulated the highest amount (p < 0.05) of both phenolics (86.6 ± 0.01 mg gallic acid equivalents/g) and flavonoids (339.6 ± 0.06 mg catechin equivalents/g).
Similarly, antioxidant activity was significantly higher (p < 0.05) when callus was cultured in period light than when grown in extended darkness. Antioxidant activity measured with
a 2,20-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS)-based assay was 350.5 ± 15.8 mmol Trolox/g
extract for callus cultured under a defined photoperiod compared to 129.1 ± 7.5 mmol Trolox/g extract from callus cultured
in darkness. Content of phenolic compounds and flavonoids was in agreement with a better antioxidant power (EC50 = 450 μg extract/mg 1,1-diphenyl-2-picrylhydrazyl) and antiradical efficiency. Results of the present study show that calli
of T. stans are a source of compounds with antioxidant activity that is favored by culture under a set photoperiod. 相似文献
9.
Terry L. Riss' David A. Sirbasku 《In vitro cellular & developmental biology. Plant》1989,25(2):136-142
Summary The effect of 17β-estradiol (E2) on growth of GH4C1 rat pituitary tumor cells was investigated under serum-free conditions and with medium containing charcoal-extracted serum.
Serum-free TRM-1 medium was a 1∶1 (vol/vol) mixture of F12-DME supplemented with 50 μg/ml gentamicin, 15 mM 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, 10 μg/ml insulin, 10 μg/ml transferrin, 10 ng/ml selenous acid, 10 nM 3,5,3′-triiodothyronine (T3), 50 μM ethanolamine, and 500 μg/ml bovine serum albumin. The cells grew continuously in TRM-1 but were E2 responsive only when growth was retarded by reducing the T3 concentration to 10 pM (TRM-MOD). Addition of 1 to 10 nM E2 to TRM-MOD increased growth by 0.3 to 0.9 cell population doublings over controls in 9 d. By using medium supplemented with
charcoal-extracted sera, basal growth became 1 to 1.5 cell population doublings in 9 d. Addition of 0.1 pM E2 to medium containing charcoal-extracted serum caused a significant increase in cell number whereas pM-nM concentrations stimulated 200 to 570% increases over controls. The effect of steroid hormone was the same in phenol-red-containing
and indicator-free medium. The data presented confirm that the major requirements for demonstration of estrogenic effects
in culture were optimum concentrations of thyroid hormones and the presence of yet-to-be-characterized serum factors.
This work was supported by National Cancer Institute (Bethesda, MD) grants CA-26617 and CA-38024, American Cancer Society
grant BC-255, and grant 2225 from The Council for Tobacco Research, U.S.A., Inc. 相似文献
10.
Masami Ogasawara David A. Sirbasku 《In vitro cellular & developmental biology. Plant》1988,24(9):911-920
Summary Growth of the MCF-7, T47D, and ZR-75-1 human breast cancer cells was established in a serum-free defined medium (MOM-1) composed
of a 1∶1 (vol/vol) mixture of Ham's F12 medium and Dulbecco's modified Eagle's medium containing 15 mM HEPES (pH 7.2), 2 mM 1-glutamine, 20 μg/ml glutathione, 10 μg/ml insulin, 10 μg/ml transferrin (Tf), 10 ng/ml selenous acid, 0.3 nM triiodothyronine, 50 μg/ml ethanolamine, 20 ng/ml epidermal, growth factor, 2.0 nM 17β-estradiol, and 1.0 mg/ml bovine serum albumin (BSA). Proliferation in MOM-1 was 50 to 70% of the serum stimulated rate.
Deletion of components from MOM-1 gave a medium (Tf-BSA) containing only HEPES, 10 μg/ml Tf, and 200 μg/ml BSA, which sustained
MCF-7 and T47D cells in a slowly dividing and mitogen responsive state; ZR-75-1 cells required Tf plus 1.0 mg/ml BSA. In Tf-BSA,
insulin and insulin-like growth factor I(IGF-I) were mitogenic with ED50 values of 2 to 3 ng/ml and 30 to 150 pg/ml, respectively, with MCF-7 cells. The T47D cells were responsive to these factors
in Tf-BSA but required 10-fold higher concentrations for ED50. At saturating concentrations, insulin and IGF-I promoted 1.5 to 3.5 cell population doublings over controls in 8 d. At≤ng/ml
concentrations, epidermal growth factor, insulin-like growth factor II, and basic fibroblast growth factor were mitogenic
for human breast cancer cells in Tf-BSA. Mitogen activities in uterus and pituitary extracts were assayed readily in Tf-BSA.
This new method offers a convenient means of comparing the potencies of growth-promoting factors on human breast cancer cells
without interfering activities known to be present in serum.
This work was supported by grants CA-38024 and CA-26617, from the National Cancer Institute, Bethesda, MD, and by American
Cancer Society grant BC-255 and grant 2225 from the Council for Tobacco Research, USA, Inc. 相似文献
11.
V. E. Kataev I. Yu. Strobykina O. V. Andreeva B. F. Garifullin R. R. Sharipova V. F. Mironov R. V. Chestnova 《Russian Journal of Bioorganic Chemistry》2011,37(4):483-491
Conjugates of the antituberculosis drug isoniazid (isonicotinyl hydrazine) and isomeric hydrazides of nicotinic and α-picolinic
acid with glycoside steviolbioside from the Stevia rebaudiana plant and the product of its acid hydrolysis, diterpenoid isosteviol, were synthesized. In addition, isosteviol hydrazide
and hydrazone derivatives as well as conjugates containing two isosteviol moieties joined by a dihydrazide linker were obtained.
The parental compounds and their synthetic derivatives were found to inhibit the in vitro growth of Mycobacterium tuberculosis (H37RV). The measured minimal concentrations of stevio-side and steviolbioside, at which the growth of M. tuberculosis was inhibited by 100% (MIC), were 7.5 and 3.8 μg/ml, respectively. MIC values for steviolbioside and isosteviol conjugates
with hydrazides of pyridine carbonic acid were within the ranges of 5–10 and 10–20 μg/ml, respectively. The maximal inhibitory
effect against M. tuberculosis was shown by the isosteviol conjugates with adipic acid dihydrazide (MIC 1.7 and 3.1 μg/ml). Antituberculosis activities
of the tested compounds were higher than the activity of antituberculosis drug Pyrizanamide (MIC 20 μg/ml) but lower than
that of antituberculosis drug isoniazid (MIC 0.02–0.04 μg/ml). 相似文献
12.
Myung-Suk Choi Ji-Hyun Park Ji Yun Min Bu-Kug Lim Byung Hyun Lee Gang Won Jung Jong-Yoon Lee Chandrakant S. Karigar Jae-Kyung Yang 《Biotechnology and Bioprocess Engineering》2008,13(3):319-324
An efficient method for release of ferulic acid from sweet potato stems was developed. Ferulic acid along with phenolic compounds
were released from stems by acid and alkaline treatments. The base hydrolysis with 0.1 N NaOH yielded the highest quantity
of total extracts (471.1 mg/g). The stems released more phenolic compounds when 0.0125∼0.025 N NaOH was employed. Where as
ferulic acid release was maximal with 0.05 N H2SO4 (0.32 mg/g). Ferulic acid was separated from phenolics by column chromatography. Among the elution solvents, ethyl acetate
fractions (80%) contained ferulic acid. Ethyl acetate eluants were further fractionated with n-hexane/ethyl acetate/formic acid (100/50/0.5, v/v/v). All fractions showed ferulic acid and phenolic compounds. Fraction
V among them was ascribed to ferulic acid with an yield of 5.41 mg/g of dry sweet potato tissue. 相似文献
13.
Summary Chili pepper (Capsicum annuum L., cv. Tampique?o 74) cell suspensions were employed to study the influence of phenylalanine and phenylpropanoids on the
total production of capsaicinoids, the hot taste compounds of chili pepper fruits. The effect of capsaicinoid precursors and
intermediates on the accumulation of lignin as an indicator of metabolic diversion was also investigated. Addition of 100
μM of either phenylalanine, cinnamic or caffeic acids to chili pepper cell cultures did not cause significant increases in total
capsaicinoids (expressed as capsaicin content, and calculated as averages of the measured values) during the growth cycle.
The highest total capsaicinoid content was recorded in cultures grown in the presence of vanillin (142.61 μg g−1 f.wt.), followed by cells treated with 100 μM vanillylamine (104.88 μg g−1 f.wt.), p-coumaric acid (72.36 μg g−1 f.wt.). and ferulic acid (34.67 μg g−1 f.wt.). Capsaicinoid content for control cells was 13.97 μg g−1 f.wt. Chili pepper cell suspensions cultured in the presence of 100 μM of either phenylalanine, or cinnamic, caffeic, or ferulic acids, or the same concentration, of vanillin and vanillylamine,
did not exhibit statistically significant differences in the content of lignin as compared with control cells. However, addition
of p-coumaric acid (100 μM) to the cultute medium significantly increased thelignin production (c. 10–15 times the contents of control cells). 相似文献
14.
Pei-Wen Hsieh Li-Chi Hsu Chern-Hsiung Lai Chin-Chung Wu Tsong-Long Hwang Yin-Ku Lin Yang-Chang Wu 《World journal of microbiology & biotechnology》2009,25(8):1461-1469
The endophytic extracts from 19 endophytes, isolated from 13 species of Taiwanese plants, were evaluated for biological activity,
including cytotoxicity, anti-platelet aggregation, and anti-inflammatory activity. The extracts of 12 endophytes exhibited
inhibitory effects on collagen-induced platelet aggregation with IC50 values of 19.85–87.64 μg/ml. Four strains, Rahnella aquatilis, Pantoea agglomerans, Rhodotorula sp., and Penicillium paxilli, also showed inhibitory effects on thrombin-induced platelet aggregation with IC50 values of 42.80–61.54 μg/ml. Additionally 12 extracts of endophytes exhibited cytotoxicities with IC50 values of 0.12–19.83 μg/ml. However, eight extracts revealed inhibitory effects on superoxide anion generation induced by
fMLP (N-formyl-l-methionyl-l-leucyl-l-phenylalanine) in human neutrophils. The extract of Rahnella aquatilis showed anti-platelet aggregation activity, and bioassay-directed fractionation led to the isolation of six compounds, including
one isoalloxazine: lumichrome (1); two isoflavones: genistein (2) and daidzein (3); two cyclic peptides: cyclo-Pro-Val (4)
and cyclo-Pro-Phe (5); and one benzenoid: methyl 2,4,5-trimethoxybenzoate (6). These results indicated that endophytes from
Taiwanese herbal plants could be useful sources for research and development of bioactive lead compounds from nature. 相似文献
15.
We compared the effects of four quaternary benzo[c]phenanthridine alkaloids – chelerythrine, chelilutine, sanguinarine, and sanguilutine – and two quaternary protoberberine
alkaloids – berberine and coptisine – on the human cell line HeLa (cervix carcinoma cells) and the yeastsSaccharomyces cerevisiae andSchizosaccharomyces japonicus var. versatilis. The ability of alkaloids to display primary fluorescence, allowed us to record their dynamics and localization in cells.
Cytotoxic, anti-microtubular, and anti-actin effects in living cells were studied. In the yeasts, neither microtubules nor
cell growth was seriously affected even at the alkaloid concentration of 100 μg/ml. The HeLa cells, however, responded to
the toxic effect of alkaloids at concentrations ranging from 1 to 50 μg/ml. IC50 values for individual alkaloids were: sanguinarine IC50 = 0.8 μg/ml, sanguilutine IC50 = 8.3 μg/ml, chelerythrine IC50 = 6.2 μg/ml, chelilutine IC50 = 5.2 μg/ml, coptisine IC50 = 2.6 μg/ml and berberine IC50 >10.0 μg/ml. In living cells, sanguinarine produced a decrease in microtubule numbers, particularly at the cell periphery,
at a concentration of 0.1 μg/ml. The other alkaloids showed a similar effect but at higher concentrations (5–50 μg/ml). The
strongest effects of sanguinarine were explained as a consequence of its easy penetration through the cell membrane owing
to nonpolar pseudobase formation and to a high degree of molecular planarity.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
Wu-Yang Huang Yi-Zhong Cai Kevin D. Hyde Harold Corke Mei Sun 《World journal of microbiology & biotechnology》2007,23(9):1253-1263
Diverse endophytic fungi exist within plant aerial tissues, with a global estimate of up to a million undescribed species.
These endophytes constitute a rich bio-resource for exploration to discover new natural products. Here we investigate fungal
endophytes associated with a medicinal plant, Nerium oleander L. (Apocynaceae). A total of 42 endophytic fungal strains were isolated from the host plant. Total antioxidant capacity,
xanthine oxidase inhibitory activity, antimicrobial activity, and total phenolic content (TPC) were evaluated for 16 representative
fungal cultures grown in improved Czapek’s broth and for the host plant. The total antioxidant capacities and phenolic contents
of the fungal cultures ranged from 9.59 to 150.79 μmol trolox/100 mL culture, and from 0.52 to 13.95 mg gallic acid/100 mL
culture, respectively. The fungal culture of an endophytic strain Chaetomium sp. showed the strongest antioxidant capacity, contained the highest level of phenolics, and to some extent inhibited xanthine
oxidase activity with an IC50 value of 109.8 μg/mL. A significant positive correlation was found between antioxidant capacity and TPC in the tested samples.
Most of the endophytic fungal cultures tested have a wide range of antimicrobial activities, which were not very strong, but
much better than those of the host plant. The major bioactive constituents of the fungal cultures were investigated using
LC-ESI-MS and GC-MS, and preliminary identification detected phenolics (e.g. phenolic acids and their derivatives, flavonoids)
and volatile and aliphatic compounds. This study shows that the endophytic fungi isolated from N. oleander can be a potential antioxidant resource. 相似文献
17.
Acetylene reduction and indoleacetic acid production by Azospirillum isolates from Cactaceous plants
Azospirillum isolates were obtained from rhizosphere soil and roots of three cactaceae species growing under arid conditions.
All Azospirillum isolates from rhizosphere and roots ofStenocereus pruinosus andStenocereus stellatus were identified asA. brasilense; isolates of surface-sterilized roots fromOpuntia ficus-indica were bothA. brasilense andA. lipoferum. Azospirilla per g of fresh root in the three species ranged from 70×103 to 11×103. The most active strains in terms of C2H2 reduction (25–49.6 nmol/h·ml) and indoleacetic acid (IAA) production (36.5–77 μg/ml) were those identified asA. brasilense and isolated from Stenocereus roots.A. lipoferum isolated from Opuntia roots produced low amounts of IAA (6.5–17.5 μg/ml) and low C2H2-reduction activity (17.8–21.2 nmol/h·ml). 相似文献
18.
The in vitro biological activity of Lepidium meyenii extracts 总被引:1,自引:0,他引:1
Valentová K Buckiová D Kren V Peknicová J Ulrichová J Simánek V 《Cell biology and toxicology》2006,22(2):91-99
The biological activity of methanolic and aqueous extracts from dehydrated hypocotyls of Lepidium meyenii (Brassicaceae, vernacular name “maca”), was studied on rat hepatocytes and human breast cancer MCF-7 cells. The extracts
did not exhibit cytotoxicity in hepatocyte primary cultures up to 10 mg/ml as measured by the MTT viability test, and lactate
dehydrogenase (LDH) and aspartate aminotransferase (AST) leakage. Moreover, after 72 h, extracts inhibited LDH and AST leakage
from the hepatocytes. When hepatocytes were intoxicated by t-butyl hydroperoxide, neither extract prevented oxidative damage. Both extracts showed weak antioxidant activity in the DPPH
radical scavenging test with IC50 values of 3.46 ± 0.16 and 0.71 ± 0.10 mg/ml, for aqueous and methanolic extracts, respectively. Thus, the observed effect
on spontaneous enzyme leakage is probably mediated through mechanisms other than antioxidant activity. Both methanolic and
aqueous extracts have shown estrogenic activity comparable with that of silymarin in MCF-7 cell line. Maca estrogenicity was
exhibited in the range from 100 to 200 μg of extract per ml. The findings in the present study show that maca does not display
in vitro hepatotoxicity. In contrast, a slight cytoprotective effect, probably not mediated by antioxidant capacity, was noted. Maca
extracts exhibited estrogenic activity comparably to the effect of silymarin in MCF-7 cells. 相似文献
19.
V. O. Tkachev E. B. Menshchikova N. K. Zenkov N. V. Kandalintseva N. N. Volsky 《Biochemistry. Biokhimii?a》2010,75(5):549-553
Synthetic water-soluble phenolic antioxidant TS-13 exhibits pronounced anti-inflammatory properties in vivo and induces intracellular signal system Nrf2/ARE. At concentrations 150–1000 μM it inhibits nitric oxide (NO) production
in mouse peritoneal macrophages. However, this compound at low concentrations (1–100 μM) paradoxically increases NO production
and decreases activity of arginase. These results are indicative of an ambiguous role of NO and its metabolites in the mechanism
of development of inflammatory reaction. 相似文献
20.
Chow-Chin Tong Yew-Keong Choong Nor-Aini-B Umar Mohamed-Mustapha Noordin Suhaila Mohamed 《World journal of microbiology & biotechnology》2009,25(4):687-695
Ganoderma lucidum powder using hot water and methanol extraction methods indicated a twofold more active cytotoxic activity with IC50 of 44 ± 3.8 μg/ml in the latter method. The representative dose-response curves of the G. lucidum crude extracts on J558 cell-lines revealed that there were great similarities between the curves which reflected rapid killing
activities. The percentage viability of the J558 cell exposed to these crude extracts was dose dependent only up to 150 μg/ml.
After which, there was no significant reduction when the dose was increased to 200 or 400 μg/ml. The morphological alterations
induced by the crude extract were examined under the phase contrast, fluorescent and electron microscopy. When J558 cells
were treated with doses higher than 50 μg/ml of the crude extract, obvious morphological changes and apoptosis occurred after
72 h. At 400 μg/ml, most of the cells showed necrosis characterized as small fragments with uniformly stained red nuclei.
The apoptotic and necrotic cells increased by 16.5 and 29.1%, respectively whereas the viable cells decreased by as much as
45.6. The mode of cell death via apoptosis was 3.6% higher than necrosis. However, these morphological changes were not observed
in the case of 3T3 cells. Results obtained from scanning electron microscopy and transmission electron microscopy further
confirmed the occurrence of various apoptotic and necrotic features. 相似文献