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1.
The dichloromethane, ethyl acetate, ethanol, and aqueous extracts of Cyclotrichium niveum (CN) and Thymus praecox subsp. caucasicus var. caucasicus (TP), Echinacea purpurea (EPU), and E. pallida (EPA) along with the essential oils of CN and TP were assessed for their anti-acetylcholinesterase (AChE) and antioxidant activities. AChE inhibition was estimated using spectrophotometric method of Ellman. Antioxidant activity was evaluated by 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferrous ion-chelating power tests. Ferric-reducing antioxidant power (FRAP) of CN and TP were also tested. CN essential oil was found to contain isomenthone (56.21%) and pulegone (19.76%). The ethyl acetate (83.11–87.98%) and dichloromethane (73.45–84.02%) extracts of CN showed the highest AChE inhibition. The ethyl acetate and ethanol extracts of TP exerted significant DPPH scavenger effect. The water extracts of CN and TP and the chloroform extract of the aerial parts of EPU displayed the highest ferrous ion-chelating effect. The leaf and flower essential oils of TP had the best FRAP.  相似文献   

2.
An indigenous strain HD-550 of Bacillus thuringiensis subsp. kenyae was found to be toxic to lepidopteran as well as dipteran insects. The cry2Aa gene (classified as cry2Aa14) from this isolate was cloned and expressed in Escherichia coli. Only a little amount of the expressed Cry2Aa14 protein was observed in soluble fraction under normal induction condition. The inclusions were non-toxic to test insects, whereas solubilized Cry2Aa14 was highly toxic to lepidopteran and dipteran insects. Cry2Aa14 protein was expressed as thioredoxin (trx) fusion protein for improving the yield of active protein. An enhancement of nearly 15% was observed in the yield of active Cry2Aa14. The TrxA-Cry2Aa14 protein purified from the solubilized fraction also showed toxicity profile similar to the wild-type protein. The LC50 values of Cry2Aa14 and TrxA-Cry2Aa14 protein against Spodoptera litura was 694 and 696 ng/cm2, respectively, while for Culex quinquefasciatus the LC50 values were 894 and 902 ng/ml, respectively. The broad spectrum toxicity of the Cry2Aa14 thus indicates that this protein could be an important component in integrated pest management. Further, the trx tag clearly led to higher yield, which facilitates protein purification for biophysical and biochemical characterization.  相似文献   

3.
Two traditional cultivated vegetables highly consumed among Northern Portuguese regions were tested for their chemical composition, nutritional profile and in vitro antioxidant properties using four assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging activity, reducing power, inhibition of β-carotene bleaching and inhibition of lipid peroxidation by thiobarbituric acid reactive substances (TBARS) assay. The studied varieties of two Brassica species, locally known as “grelos” (rape) and “espigos” (“tronchuda” cabbage) are nutritionally well-balanced vegetables; particularly “tronchuda” cabbage revealed the highest levels of moisture, proteins, fat, energy, β-carotene and vitamin C; rape gave the highest contents of ash, carbohydrates, sugars (including fructose, glucose, sucrose and raffinose), essential n-3 fatty acid α-linolenic acid, and the best ratios of PUFA/SFA and n-6/n-3 fatty acids, tocopherols, lycopene, chlorophylls, phenolics, flavonoids, and also the highest antioxidant properties. The health benefits associated to the antioxidant properties reinforce their contribution to a healthy and balanced diet, highlight the interest of their consumption, validate the empirical use and add new values to traditional/regional products which have been used for a long time.  相似文献   

4.
The present study aimed to determine whether the leaves of Turnera ulmifolia Linn. var. elegans extract exert significant antioxidant activity. The antioxidant activity of its hydroethanolic extract (HEETU) was evaluated by assessing (a) its radical scavenging ability in vitro, and (b) its in vivo effect on lipid peroxidation and antioxidant enzyme activities. The in vitro antioxidant assay (DPPH) clearly supported HEETU free radical scavenging potential. Moreover, glutathione content and antioxidant enzyme activities (glutathione peroxidase, superoxide dismutase and catalase) were significantly enhanced in CCl4-treated rats due to oral HEETU-treatment (500 mg/kg b.w.) over 7 and 21 days. In addition, an improvement was observed in lipid peroxidation and serum biochemical parameters (aspartate aminotransferase and alanine aminotransferase), indicating a protective effect against CCl4-induced liver injuries, confirmed by histopathological studies. The HEETU effect was comparable to the standard drug Legalon® (50 mg/kg b.w.) under the same experimental condition. Quantitative analysis of the HPLC extract revealed the presence of flavonoids, wich mediate the effects of antioxidant and oxidative stress. In conclusion, extract components exhibit antioxidant and hepatoprotective activities in vitro and in vivo.  相似文献   

5.
Phenolic and organic acid profiles of aqueous extracts from Pieris brassicae material and the host kale (Brassica oleracea L. var. acephala) leaves were determined by HPLC/UV–DAD/MSn-ESI and HPLC–UV, respectively. The identified phenolics included acylated and nonacylated flavonoid glycosides, hydroxycinnamic acyl gentiobiosides, and sulphate phenolics. Kale exhibited the highest content (11 g/kg lyophilized extract), while no phenolics were identified in the butterflies or exuviae. Nine different organic acids were characterized in the materials, with kale showing the highest amount (112 g/kg lyophilized extract). With the exception of the exuviae extract, the rest were screened for bioactivity. Using spectrophotometric microassays, all exhibited antiradical capacity against DPPH and NO in a concentration-dependent way, whereas only kale and excrement extracts were active against superoxide. All displayed activity on intestinal smooth muscle, albeit with distinct relaxation–contraction profiles. Larvae and butterfly extracts were more efficacious for intestinal relaxation than was kale extract, whereas excrement extract evoked only contractions, thus evidencing their different compositions. Collectively, these results show that P. brassicae sequesters and metabolizes kale’s phenolic compounds. Moreover, the extract’s bioactivities suggest that they may constitute an interesting source of bioactive compounds whose complex chemical structures preclude either synthesis or isolation.  相似文献   

6.
This study was designed to examine the chemical composition and antioxidant activity of the essential oils and methanol extracts of Myrtus communis var. italica L. leaf, stem and flower. Myrtle leaf and flower were the valuable organs for the essential oil production representing a yield of 0.61% and 0.30% (w/w), respectively. The essential oil composition of myrtle leaf and flower was characterized by high proportions of α-pinene, the main compound of monoterpene hydrocarbon class, with 58.05% for leaf and 17.53% for flower. Stem was rich in oxygenated monoterpenes, largely due to 1,8-cineole with 32.84%. The total phenol contents varied between different myrtle parts; leaf extract had higher total phenol content (33.67 mg GAE/g) than flower (15.70 mg GAE/g) and stem (11.11 mg GAE/g) extracts. Significant differences were also found in total tannin contents among different myrtle parts, representing 26.55 mg GAE/g in leaf, 11.95 mg GAE/g in flower, 3.33 mg GAE/g in stem. The highest contents of total flavonoids and condensed tannins were observed in stem (5.17 and 1.99 mg CE/g, respectively) and leaf (3 and 1.22 mg CE/g, respectively) extracts. The HPLC analysis indicated that the main phenolic class was hydrolysable tannins (gallotannins) in leaf (79.39%, 8.90 mg/g) and flower (60.00%, 3.50 mg/g) while the stem was characterized by the predominance of flavonoid class (61.38%, 1.86 mg/g) due to the high presence of catechin (36.91%, 1.12 mg/g). Antioxidant activities of the essential oil and the methanolic extract from different myrtle parts were evaluated by using DPPH radical scavenging, β-carotene-linoleic acid bleaching, reducing power and metal chelating activity assays. In all tests, methanolic extracts of different myrtle parts showed better antioxidant activity than essential oils.  相似文献   

7.
Bacillus thuringiensis (Bt) is the best known and most widely used of all pesticidal microbes. The aim of this study was to assess the toxicity of a new formulation of Bacillus thuringiensis var israelensis SH-14 in rats through acute dermal toxicity, dermal and eye irritation experiments. The acute dermal toxicity and dermal and eye irritation studies were performed using rabbits according to the United States Environmental Protection Agency guidelines 885.3100, 870.2500 and 870.2500, respectively. The skin sensitization study was carried out in accordance to the EPA OPPTS 870.2600 using guinea pigs. There was no mortality and no evidence of treatment-related toxicity in acute dermal toxicity test. No dermal responses, including erythema/eschar or edema, were found in rabbits treated with the new formulation of Bti SH-14. Minimum response was observed after eye application of test substance. No skin sensitization reactions were observed after the challenge with the new formulation of Bti SH-14 in the Bti SH-14-treated guinea pigs. In summary, the present study demonstrated that the new formulation of Bti SH-14 is not acutely toxic via dermal route, has low eye irritation and would not cause dermal irritation or hypersensitivity to tested animals.  相似文献   

8.
Blue-green algae (BGA) have been consumed as food and herbal medicine for centuries. However, safety for their consumption has not been well investigated. This study was undertaken to evaluate in vitro and in vivo toxicity of cultivated Nostoc commune var. sphaeroides Kützing (NO) and Spirulina platensis (SP). Neither NO nor SP contained detectable levels of microcystin (MC)-LA, MC-RR, MC-LW and MC-LR by LC/MS/MS. Cell viability remained ∼70-80% when HepG2 cells were incubated with 0-500 μg/ml of hexane, chloroform, methanol and water-extractable fractions of NO and SP. Four-week-old male and female C57BL/6J mice were fed an AIN-93G/M diet supplemented with 0%, 2.5% or 5% of NO and SP (wt/wt) for 6 months. For both genders, BGA-rich diets did not induce noticeable abnormality in weight gain and plasma alanine aminotransferase (ALT) and aspartate aminotransferase concentrations except a significant increase in plasma ALT levels by 2.5% NO supplementation in male mice at 6 month. Histopathological analysis of livers, however, indicated that BGA did not cause significant liver damage compared with controls. In conclusion, our results suggest that NO and SP are free of MC and the long-term dietary supplementation of up to 5% of the BGA may be consumed without evident toxic side-effects.  相似文献   

9.
In the present study, chemical compositions, antimicrobial and antioxidant activities of the essential oils of Sideritis erythrantha var. erythrantha (SE) and Sideritis erythrantha var. cedretorum (SC), which are endemic taxa in Turkey, were investigated. The essential oils obtained by hydrodistillation were analyzed by gas chromatography–mass spectrometry (GC–MS). α-Pinene was the major component of the essential oils of SC and SE. SC essential oil was as effective as antibiotic against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus faecalis (VRE), ampicillin resistant Haemophilusinfluenzae and vancomycin sensitive E. faecalis. Similarly, SE essential oil was also as effective as antibiotic against VRE and ampicillin resistant H. influenzae. Antioxidant activities of the essential oils of SC and SE were determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH), β-carotene/linoleic acid and reducing power. Both essential oils exhibited weak antioxidant activity. This is the first report on antimicrobial and antioxidant activities of the essential oils of SC and SE.  相似文献   

10.
Tilia species are well known around the world for their properties in traditional medicine. Antinociceptive activity of hexane, methanol and aqueous extracts from Tilia americana var. mexicana inflorescences was evaluated in the pain-induced functional impairment model in rats (PIFIR). A preliminar 300 mg/kg dosage of aqueous extracts i.p., but not the same dose of methanol or hexane extract, produced an antinociceptive response in rats similar to that of tramadol (17.8 mg/kg i.p.). A dose-response curve from aqueous extract allowed the determination of ED50 = 364.97 mg/kg in comparison to ED50 = 10.35 mg/kg for tramadol in this model. A previous HPLC-DAD analysis corroborated by an HPLC-MS technique in this study demonstrated the flavonoid composition in this Tilia aqueous extract revealing the presence of glycosides mainly derived from quercetin. Thus, Tilia aqueous extract and quercetin were tested at 30 and/or 100 mg/kg dosages i.p. in the PIFIR and formalin models producing a significant and dose-dependent antinociceptive response resembling that produced by a total and a partial agonist of 5-HT1A receptors like 8-OH-DPAT (0.1 mg/kg, s.c.) and buspirone (5 mg/kg, i.p.), respectively. In all the treatments, antinociceptive response was inhibited in the presence of WAY 100635 (0.12 mg/kg, i.p.). Our results support the analgesic activity of T. americana var. mexicana inflorescences attributed by folk medicine; they also indicate that quercetin is partly responsible for this pharmacological activity that is likely mediated by serotonin 5-HT1A receptors.  相似文献   

11.
The essential oil composition of Rosmarinus officinalis var. typicus and var. troglodytorum endemic to Tunisia, and growing wild in different bioclimates, was determined by GC and GC–MS. Oils were assessed for their antimicrobial and antioxidant activity. A variation of the chemical composition attributed to varieties rather than to bioclimates was revealed. 1.8-Cineole (47.2–27.5%) and camphor (12.9–27.9%) were identified as the main constituents of var. typicus and var. troglodytorum, respectively. The principal component analysis performed on oil constituents for all the populations allowed the distinction of two distinct population groups in accordance to the varietal subdivision. Based on the determination of the diameter of inhibition and the determination of the minimum inhibitory concentration, a low to moderate antimicrobial activity according to oils was revealed against eight bacteria tested. However, oils from var. troglodytorum showed higher bactericidal effect than those from var. typicus. The oils’ antioxidant activity, determined by 1,1-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric reducing (FRAP) assay and β-carotene bleaching test, was relatively high. The highest activity was found in oils from var. troglodytorum and in one population of var. typicus from the upper semi-arid bioclimate.  相似文献   

12.
High performance liquid chromatography coupled with electrospray ionization multi-stage tandem mass spectrometry (HPLC–ESI-MSn) and triple quadrupole mass spectrometric detection (HPLC–ESI-MS/MS), respectively, had been employed for the simultaneous identification and quantification of steroidal saponins in the rhizomes of Parispolyphylla var. yunnanensis and P. polyphylla var. chinensis, which are the qualified plants of “Chonglou” in Chinese. The HPLC experiments were performed by means of a reversed-phase C-18 column and a binary mobile phase system consisting of 0.1% aqueous formic acid and acetonitrile under gradient elution conditions. The characteristic fragmentation patterns of diosgenin- and pennogenin-type steroidal saponins were investigated using ESI-MSn in negative ion mode. The MSn data of the [M−H] ions provided structural information on the sugar sequence of the oligosaccharide chains and the aglycones of steroidal saponins. As a result, ten and seven saponins were determined in P. polyphylla var. yunnanensis and P. polyphylla var. chinensis, respectively, including four unknown compounds. One unknown compound was tentatively identified as diosgenin-3-O-α-l-rhamnopyranosyl(1 → 4) [α-l-rhamnopyranosyl(1 → 2)]-β-d-glucopyranoside and the aglycones of the other three new compounds were reported from Chonglou for the first time. The developed HPLC–ESI-MS/MS method was validated and found to be satisfactorily linear, selective and robust. The limits of detection (LODs) and quantitation (LOQs) ranged, respectively, from 0.5 to 10 ng/mL and 2 to 34 ng/mL depending on six various compounds. The intra- and inter-day precisions of the method were evaluated and were less than 5.0%. Recoveries ranged from 92% to 104% for all compounds. The established quality evaluation method was successfully used for simultaneous quantification of six predominant steroidal saponins in the rhizomes of these two Paris species.  相似文献   

13.
Bacillus thuringiensis Cry toxins are widely used as biocontrol agents in bioinsecticides and transgenic plants. In the three domain-Cry toxins, domain II has been identified as an important determinant of their highly specific activity against insects. In this work, we assessed the role in membrane associated proteolysis and toxicity in Colorado potato beetle (CPB) of a previously reported ADAM recognition motif present in Cry3Aa toxin domain II. We used site-directed mutagenesis to modify the Bacillus thuringiensis cry3A gene in amino acid residues 344, 346, 347, 351 and 353 of the ADAM recognition motif in Cry3Aa toxin. Cry3Aa toxin mutants displayed decreased toxicity when compared to the wild type toxin and impaired ability to compete CPB brush border membrane associated cleavage of an ADAM fluorogenic substrate. Although the proteolytic profile of Cry3Aa toxin mutants generated by brush border membrane associated proteases was similar to that of Cry3Aa toxin, the metalloprotease inhibitor 1,10-phenanthroline was less efficient on the proteolysis of mutants than on that of the wild type toxin. The relevance of the Cry3Aa-ADAM interaction through the predicted recognition sequence was further confirmed by analyzing the effect of membrane integrity disturbance on Cry3Aa toxin membrane associated proteolysis and CPB larvae toxicity. Data support that Cry3Aa proteolysis, as a result of the interaction with ADAM through the Cry3Aa recognition motif, is essential for Cry3Aa toxic action in CPB. Detailed knowledge of Cry3Aa interaction with CPB midgut membrane should facilitate the development of more effective Bt based products against this devastating pest and other Coleoptera.  相似文献   

14.
This study aimed to explore the antioxidant and DNA protection abilities of hydroalcoholic extracts from fruits of Anadenanthera colubrina (ACHE), Libidibia ferrea (LFHE) and Pityrocarpa moniliformis (PMHE). These extracts were tested by five antioxidant methods (phosphomolibdenium and reducing power assays; superoxide, hydrogen peroxide and nitric oxide scavenging) and DNA protection capacity. Total phenolic content was measured by Folin-Ciocalteu method. ACHE exhibited the highest phenolic content (578 mg/g GAE), followed by LFHE (460 mg/g GAE) and PMHE (448 mg/g GAE). In phosphomolibdenium assay, ACHE showed 24.81% of activity in relation to ascorbic acid, whereas LFHE and PMHE had 21.08% and 18.05%, respectively. These plants showed high ability to inhibit reactive species tested with IC50 values ranged from 10.66 to 14.37 μg/mL for superoxide radical; 26.05 to 45.43 μg/mL for hydrogen peroxide; 178.42 to 182.98 μg/mL for reducing power; and 199.2 to 283 μg/mL for nitric oxide. Furthermore, these extracts had capacity to break the DNA damage induced by hydroxyl radicals. The antioxidant activity of these plants is related with their higher phenolic content and show that they may be used as source of bioactive compounds, relevant to the maintenance of oxidative stability of the food matrix, cosmetics and/or pharmaceutical preparations.  相似文献   

15.
The aim of the present study was to compare the toxic effects of the venoms from Hemiscorpius lepturus (H. lepturus), Androctonus crassicauda (A. crassicauda) and Mesobuthus eupeus (M. eupeus). For this purpose, three in vitro models were employed to compare the toxic effects of various concentrations of the venoms from these three scorpions, namely: hemolytic potential using human RBCs, phospholipase activity using Saubouraud's dextrose agar (SDA) supplemented with 2% egg yolk and lactate dehydrogenase (LDH) enzyme releasing effect using K562 leukemia cell line. In addition, the neutralizing effectiveness of the antivenom against these toxic properties was assessed. The results showed that, unlike the venoms from A. crassicauda and M. eupeus, the venom from H. lepturus produced dose-dependent lysis of human RBCs and showed phospholipase activity. However, all the tested venoms showed variable degrees of LDH releasing properties. The venom from H. lepturus had highest and the venom from M. eupeus had the lowest LDH releasing effect. The antivenom effectively inhibited all the tested toxicities. In conclusion, these results suggest that the venoms from the studied scorpions have variable toxic properties, which may explain the underlying reason for the differences in their clinical manifestations. In addition, the antivenom was effective in neutralizing all the tested toxic effects.  相似文献   

16.
Dinoflagellates in the genus Gambierdiscus produce toxins that bioaccumulate in tropical and sub-tropical fishes causing ciguatera fish poisoning (CFP). Little is known about the diversity and distribution of Gambierdiscus species, the degree to which individual species vary in toxicity, and the role each plays in causing CFP. This paper presents the first global distribution of Gambierdiscus species. Phylogenetic analyses of the existing isolates indicate that five species are endemic to the Atlantic (including the Caribbean/West Indies and Gulf of Mexico), five are endemic to the tropical Pacific, and that two species, Gambierdiscus carpenteri and Gambierdiscus caribaeus are globally distributed. The differences in Gambierdiscus species composition in the Atlantic and Pacific correlated with structural differences in the ciguatoxins reported from Atlantic and Pacific fish. This correlation supports the hypothesis that Gambierdiscus species in each region produce different toxin suites. A literature survey indicated a >100-fold variation in toxicity among species compared with a 2 to 9-fold within species variation due to changing growth conditions. These observations suggest that CFP events are driven more by inherent differences in species toxicity than by environmental modulation. How variations in species toxicity may affect the development of an early warning system for CFP is discussed.  相似文献   

17.
Major toxins from skin extracts of 18 specimens of six Atelopus toad species collected in Panama were analyzed. Chiriquitoxin was identified using 1H NMR in A. limosus and A. glyphus for the first time. Zetekitoxin in A. zeteki and tetrodotoxin in A. varius, A. chiriquiensis and A. zeteki were identified again. Furthermore, A. certus was suggested to contain a water-soluble toxin other than tetrodotoxin.  相似文献   

18.
Numerous plant species worldwide including Palicourea marcgravii and Tanaecium bilabiatum in Brazil cause sudden death and are known to contain monofluoroacetate (MFA). Other species in Brazil including some species traditionally assigned to Mascagnia but now properly called Amorimia species and other Palicourea species are reported to cause sudden death in livestock and are suspected to contain MFA due to the similarity of clinical signs. In this study, an HPLC-APCI-MS method to detect and quantify MFA was developed and was used to investigate plant material from field collections and/or herbarium specimens of Mascagnia, Amorimia, and Palicourea species suspected of causing sudden death. MFA was detected in Amorimia amazonica, Amorimia camporum, Amorimia exotropica, Amorimia pubiflora, Amorimia rigida, and Amorimia septentrionalis as well as Palicourea aeneofusca. MFA concentrations differ greatly between Palicourea species and Amorimia species, which may explain the incidence of poisoning and the amount of plant material required to cause sudden death between these taxa.  相似文献   

19.
This study was carried out to evaluate the anticandidal effects of bioconverted product, obtained from the microbial conversion of cabbage (Brassicaoleracea) by a bacterial strain Pseudomonassyringe pv. T1 (Ps-T1) against various isolates of Candida species. The diameters of zones of inhibition of bioconverted product of cabbage (10 μl, corresponding to 500 μg/disc) against Candidaalbicans KACC 30003 and 30062, Candidageochares KACC 30061, Candidasaitoana KACC 41238 and Candidaglabrata P00368 were found between 10 ± 1 and 16 ± 0.8 mm. The bioconverted product was tested for the minimum inhibitory and minimum fungicidal concentration values against the tested pathogens which were found in the range of 125-500 and 125-500 μg/ml, respectively. On the viable counts of the tested fungal pathogens, the bioconverted product showed a remarkable anticandidal effect. Also the study of using scanning electron microscopy on the morphology of C.albicans KACC 30062 revealed potential detrimental effect of bioconverted product at MIC concentration. The results of this study suggest that bioconverted product of cabbage by Ps-T1 holds potential therapeutic value and medicinal significance to control Candida species.  相似文献   

20.
A standardized extract of the fruits of Solanum distichum has previously been shown to possess anti-hypertensive activity in rats (ED50 about 1 mg/kg). Earlier acute toxicity studies had shown that single doses up to 2 g/kg orally or intraperitoneally failed to show any signs of morbidity. To study its potential long-term toxicity, rats of either sex were fed orally 1 g/kg of the extract daily over a period of 4 weeks to 6 months. The extract did not affect food intake or rate of growth of the animals. Blood counts and other hematological parameters remained unaffected. Treatment for 4 weeks had no effect on plasma cholesterol or blood urea nitrogen in both sexes, but extended treatment to 6 months tended to lower both parameters. Plasma creatinine, liver enzymes and fasting blood sugar, plasma electrolytes, total protein and albumin were not altered. Gross necropsy showed a 20% increase in liver to body weight ratios after 6 months. None of the body organs tested showed any histopathological changes. Bearing in mind that the dose of the extract used in this study was several 100 times greater than its ED50, the present findings point to the wide safety margin of the extract.  相似文献   

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