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1.
This research expresses the potential of the bacterial activity present in the organic extracts obtained from Penicillium sp., isolated from the esponge Irciniafelix. This activity was evaluated through agar diffusion test and Minimal Inhibitory Concentration (MIC). The susceptibility trials of organic fractions were carried out against Staphylococcus aureus, S. epidermidis, Bacillus cereus and B. subtilis. The use of the chromatographic techniques (CLV and TLC), permitted to obtain bioactive organic extracts of different polarities, of which only the EtOAc and MeOH fractions inhibited the growth of the bacteria used. Of the EtOAc fractionation, only fraction number 3 EtOAc/Hex presented greatest activity against the Gram-positive bacteria. Number 1 EtOAc/Hex fraction increased its activity against S. aureus (24 mm) and S. epidermidis (25 mm), which can be explained by the loss of possible antagonistic effect during the fractionation process. The CMI trials were carried out for the EtOAc number I subfraction against S. aureus, S. epidermidis, B. cereus and B. subtilis, wich was clinical interest, and shows the potential of this organic extract as antimicrobial agent.  相似文献   

2.
18S ribosomal DNA and internal transcribed spacer 2 (ITS-2) full-length sequences, each of which was sequenced three times, were used to construct phylogenetic trees with alignments based on secondary structures, in order to elucidate genealogical relationships within the Aplysinidae (Verongida). The first poriferan ITS-2 secondary structures are reported. Altogether 11 Aplysina sponges and 3 additional sponges (Verongula gigantea, Aiolochroia crassa, Smenospongia aurea) from tropical and subtropical oceans were analyzed. Based on these molecular studies, S. aurea, which is currently affiliated with the Dictyoceratida, should be reclassified to the Verongida. Aplysina appears as monophyletic. A soft form of Aplysina lacunosa was separated from other Aplysina and stands at a basal position in both 18S and ITS-2 trees. Based on ITS-2 sequence information, the Aplysina sponges could be distinguished into a single Caribbean–Eastern Pacific cluster and a Mediterranean cluster. The species concept for Aplysina sponges as well as a phylogenetic history with a possibly Tethyan origin is discussed.Reviewing Editor: Dr. Martin Kreitman  相似文献   

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Feeding biology in mollusks has important biological, ecological and evolutionary implications because many of the characteristics we observe in mollusks arise from their co-evolution with diet organisms. We investigated the relationship between the opisthobranch Tylodina perversa and the sponges Aplysina aerophoba and Aplysina cavernicola in order to ascertain the trophic interactions between them. The opisthobranch preferred specimens of Aplysina aerophoba inhabiting shallow overdeep waters, ectosome of Aplysina aerophoba over choanosome, and showed no preference for Aplysina cavernicola . The sponge Aplysina cavernicola lacks the cyanobacteria abundant in the ectosome of Aplysina aerophoba . Our study shows that the opisthobranch Tylodina perversa actively selects for sponges or sponge zones with high concentration of cyanobacteria, i.e. only a fraction of the ingested material is of animal origin. Addition of cyanobacteria to symbiont-free sponge material induced a shift in mollusk preference. Our results cast doubt over the widely recognized qualification of Tylodina perversa as a carnivorous sponge feeder and show evidence that cyanobacteria determine the opisthobranch food selection. Whether this is an isolated example of how symbionts may determine trophic interactions between hosts and predators or it is widespread in benthic organisms remains an open question that requires further investigation.  © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 78 , 429–438.  相似文献   

6.
A total of seven microsatellites out of 88 isolated from a genomic library enriched for (CA)n and (GA)n repeats were characterized in the Mediterranean marine sponge Scopalina lophyropoda. The microsatellite motifs were large (34.81 ± 13.9 bp) and imperfect. The seven microsatellite loci were screened in 30 individuals collected from Blanes, northwestern Mediterranean. All of them were polymorphic (allele numbers and observed heterozygosities ranged from 3 to 6 and from 0.16 to 0.76, respectively). No significant linkage disequilibrium between pairs of loci and no departure from Hardy–Weinberg equilibrium were found. These markers are therefore promising for studies of the population structure of the species.  相似文献   

7.
Cut specimens of the common reef sponge of the Verongid family, Aplysina fistularis, were retained in flow‐through seawater tanks over a six‐week period to assess the metabolite profile of the sponge when subjected to stress, compare the profile with the source material, and assess the preliminary feasibility of the protocol for sponge culture. The living specimens were harvested, extracted with MeOH/CH2Cl2 1 : 1, and subjected to column chromatography to identify metabolites. The brominated isoxazoline compounds, aerothionin ( 1 ) and 11‐oxoaerothionin ( 2 ), along with aeroplysinin 2 ( 3 ) and 2‐(3,5‐dibromo‐4‐hydroxyphenol)acetamide ( 4 ), were detected in the cuttings from the tank‐maintained sponge. An examination of the metabolite profile of the sponge from the natural habitat showed that the compounds 1 and 2 were present. The identities of all the compounds were ascertained by analysis of the mass‐spectral data and NMR spectra (1H, 13C, HMBC, and HSQC) of the compounds, which were compared with reported data. The survival rate was 44% with limited necrosis or exposed skeletal tissue being observed in eight of the 18 cuttings, suggesting that protocol modifications would be required for culturing the sponge.  相似文献   

8.
The aim of this work was to select endophytic fungi from mangrove plants that produced antimicrobial substances. Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) or minimal fungicidal concentrations (MFC) of crude extracts from 150 isolates were determined against potential human pathogens by a colorimetric microdilution method. Ninety-two isolates (61.3%) produced inhibitory compounds. Most of the extracts (28–32%) inhibited Staphylococcus aureus (MIC/MBC 4–200/64–200 μg ml−1). Only two extracts inhibited Pseudomonas aeruginosa (MIC/MBC 200/>200 μg ml−1). 25.5 and 11.7% inhibited Microsporum gypseum and Cryptococcus neoformans (MIC/MFC 4–200/8–200 μg ml−1 and 8–200/8–200 μg ml−1, respectively), while 7.5% were active against Candida albicans (MIC/MFC 32–200/32–200 μg ml−1). None of the extracts inhibited Escherichia coli. The most active fungal extracts were from six genera, Acremonium, Diaporthe, Hypoxylon, Pestalotiopsis, Phomopsis, and Xylaria as identified using morphological and molecular methods. Phomopsis sp. MA194 (GU592007, GU592018) isolated from Rhizophora apiculata showed the broadest antimicrobial spectrum with low MIC values of 8–32 μg ml−1against Gram-positive bacteria, yeasts and M. gypseum. It was concluded that endophytic fungi from mangrove plants are diverse, many produce compounds with antimicrobial activity and could be suitable sources of new antimicrobial natural products.  相似文献   

9.
Three crude extracts of Aplysina caissara, a marine sponge endemic to Brazil, were tested against a hepatoma cell line and Mycobacterium tuberculosis. The results demonstrate that all extracts are toxic and capable of inhibiting cellular growth. Additionally, the extracts produced morphological aberrations and inhibited cell attachment to culture substrates. These effects were dose/time dependent. Our results also suggest that reactive oxygen species (ROS) production is not involved in the cytotoxic processes levied by the extracts employed in this study and that active metabolites are likely to be present in the polar fractions of the crude extracts. Finally, our results indicate that all three extracts exhibit a moderate anti-tuberculosis capacity, and that the removal of an extract's lipid fraction appears to diminish this activity.  相似文献   

10.
An antibiotic-producing actinomycete was isolated from Nigerian soil and assigned to the genusStreptomyces. The antibiotic had antimicrobial activity on solid agar against both Gram-positive and Gram-negative bacteria as well as fungi.
Résumé On a isolé un actinomycète producteur d'antibiotique d'un sol Nigérian et on lui a assigné le genreStreptomyces. L'antibiotique avait une activité antimicrobienne sur agar solide tant contre les bactéries gram-positives et les bactéries Gram-négatives que les fungi.
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11.
Four pentacyclic tritepenes were isolated from Combretum imberbe Engl. & Diels, of which two are novel glycosidic derivatives of 1alpha,3beta,23-trihydroxyolean-12-en-29-oic acid (hydroxyimberbic acid). Terminalia stuhlmannii Engl. & Diels stem bark yielded two glycosides of hydroxyimberbic acid, one of which is reported for the first time. The structures of the isolated compounds were elucidated by spectroscopic methods. Several of the compounds had antibacterial activity, imberbic acid showing particularly potent activity against Mycobacterium fortuitum and Staphylococcus aureus.  相似文献   

12.
AIMS: Although probiotic prophylaxis has been suggested to prevent small bowel bacterial overgrowth, bacterial translocation and infection of pancreatic necrosis in severe acute pancreatitis, limited data are available on their antimicrobial activity. METHODS AND RESULTS: Using the well-diffusion method, we studied the antimicrobial properties of a multispecies probiotic product (Ecologic 641) against a collection of pathogens cultured from infected pancreatic necrosis. All individual probiotic strains included in the multispecies preparation were able to inhibit the growth of the pathogens to some extent. However, the combination of the individual strains (i.e. the multispecies preparation) was able to inhibit all pathogenic isolates. Probiotic-free supernatants adjusted to pH 7 were not able to inhibit pathogen growth. CONCLUSION: Ecologic 641 is capable of inhibiting growth of a wide variety of pathogens isolated from infected pancreatic necrosis. The antimicrobial properties are to a large extent explained by the production of organic acids. SIGNIFICANCE AND IMPACT OF THE STUDY: Ecologic 641 is currently being used in a Dutch nationwide double-blind, placebo-controlled, randomized multicentre trial in patients with predicted severe acute pancreatitis.  相似文献   

13.
A range of biologically active secondary metabolites with pharmacological application has been reported to occur in marine sponges. The present study was undertaken to provide a set of data on the safety of a hydro-alcoholic extract (ALE) and an aqueous fraction (AQE) from Aplysina fulva Pallas, 1766 (Aplysinidae, Verongida, Porifera). Salmonella typhimurium strains TA97, TA98, TA100 and TA102, Escherichia coli strains PQ65, OG40, OG100, PQ35 and PQ37 and Balb/c 3T3 mouse fibroblasts were used to detect induction of DNA lesions by ALE and AQE. Assays used for these analyses were a bacterial (reverse) mutation assay (Ames test), the SOS-chromotest and the comet assay. Both extracts presented identical infrared 2-oxazolidone spectra. ALE treatment induced a higher frequency of type-4 comets, indicative of increasing DNA migration, in the alkaline comet assay. ALE also induced a weak genotoxic effect, as expressed by the induction factor (IF) values in the test with E. coli strain PQ35 (IF=1.5) and by cytotoxic effects in strains PQ35, PQ65 and PQ37. Positive SOS induction (IF=1.7) was detected in strain PQ37 treated with diluted AQE. No genotoxic effects were observed in strains PQ35, PQ65, OG40 and OG 100 after treatment with AQE dilutions. Using the bacterial (reverse) mutation test and survival assays with or without S9 mix, after 60min of pre-incubation, we observed for strain TA97 treated with ALE a weak mutagenic response (MI=2.2), while cytotoxic effects were seen for strains TA98, TA100 and TA102. AQE did not show mutagenic activity in any of the strains tested, but a weak cytotoxic effect was noted in strain TA102. Our data suggest that both ALE and AQE from A. fulva induce DNA breaks leading to cytotoxicity and mutagenicity under the conditions used.  相似文献   

14.
Three thiosulfinates were isolated from oil-macerated garlic extract, and their structures were identified as 2-propene-1-sulfinothioic acid S-(Z,E)-1-propenyl ester [AllS(O)SPn-(Z,E)], 2-propenesulfinothioic acid S-methyl ester [AllS(O)SMe], and methanesulfinothioic acid S-(Z,E)-1-propenyl ester [MeS(O)SPn-(Z,E)]. This is the first report of isolating these thiosulfinates from oil-macerated garlic extract. Antimicrobial activities of AllS(O)SPn-(Z,E) and AllS(O)SMe against Gram-positive and negative bacteria and yeasts were compared with 2-propene-1-sulfinothioic acid S-2-propenyl ester [AllS(O)SAll, allicin] which is well-known as the major thiosulfinate in garlic. Antimicrobial activity of AllS(O)SMe and AllS(O)SPn-(Z,E) were comparable and inferior to that of allicin, respectively. This result suggested that the antimicrobial activity of 2-propene sulfinothioic acid S-alk(en)yl esters were affected by alk(en)yl groups. The order for antimicrobial activity was: allyl > or = methyl > propenyl.  相似文献   

15.
Plumbagin is a naturally occurring naphthoquinone isolated from roots of Plumbago scandens. The plant was collected at the Campus of Funda??o Oswaldo Cruz, Rio de Janeiro, Brazil. P. scandens is used as a traditional medicine for the treatment of several diseases. The antimicrobial activity of plumbagin was evaluated using the macrodilution method. The compound exhibited relatively specific activity against bacteria and yeast. The minimum inhibitory concentration test showed the growth inhibiton of Staphylococcus aureus at a concentration of 1.56 g/ml and of Candida albicans at a concentration of 0.78 g/ml. These results suggest the naphthoquinone plumbagin as a promising antimicrobial agent.  相似文献   

16.
Çinar  Melih Ertan  Katagan  Tuncer  Ergen  Zeki  Sezgin  Murat 《Hydrobiologia》2002,472(1-3):107-117
The cavities and outer surfaces of 20 individuals of the sponge Sarcotragus muscarum collected from the Turkish Aegean coast during July–September 1993 contained a total of 148 zoobenthic species with 5299 individuals belonging to seven taxonomic groups. Among these, Polychaeta accounted for 60% of the total number of species, while Crustacea comprised 71% of the total number of individuals and 40% of the wet weight of biomass. The amphipod and decapod crustaceans Tritaeta gibbosa and Synalpheus gambarelloides, and the bivalve Hiatella arctica, were the most abundant species on the sponge samples both in terms of number of individuals and biomass values. The community structure inside the sponges was greatly influenced by the nature of the substratum around the sponge, and by the overwhelming population of the Lessepsian echinoderm Ophiactis savignyi. Number of species, biomass and diversity index values were found to be positively related to the sponge volume. Mean density and biomass of the associated taxa are 0.22 ind cm–3 and 11.63 mg cm–3, respectively.  相似文献   

17.
采用琼脂稀释法研究西瓜藤提取物的体外抑菌作用,用小鼠腹腔注射金黄色葡萄球菌法研究80%醇提物的体内抑菌作用。结果表明:西瓜藤提取物对金黄色葡萄球菌、大肠埃希氏菌、铜绿假单胞菌、伤寒沙门氏菌、枯草芽孢杆菌和肺炎克雷伯氏菌均有不同程度的抑制作用,但对链球菌作用不明显。其中80%醇提取物和乙酸乙酯萃取物抑制金黄色葡萄球菌活性最好,其最低抑菌浓度(MIC)分别为4.2、8.4mg.mL-1。体内实验也表明,乙醇提取物具有较好的抑菌作用。西瓜藤提取物具有抑菌活性,在抑菌方面有一定开发前景。  相似文献   

18.
Antibacterial and antifungal properties of wax and hexane extracts of Citrus spp. peels were tested using bioautographic and microdilution techniques against three plant pathogenic fungi (Penicillium digitatum, Curvularia sp., and Colletotrichum sp.), two human pathogens (Trichophyton mentagrophytes and Microsporum canis), and two opportunistic bacteria (Escherichia coli and Staphylococcus aureus). Two polymethoxylated flavonoids and a coumarin derivative, were isolated and identified from peel extracts, which presented antimicrobial activity especially against M. canis and T. mentagrophytes: 4',5,6,7,8-pentamethoxyflavone (tangeritin) and 3',4',5,6,7,8-hexamethoxyflavone (nobiletin) from C. reticulata; and 6,7-dimethoxycoumarin (also known as escoparone, scoparone or scoparin) from C. limon.  相似文献   

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Baccharis dracunculifolia D.C. (Asteraceae) is the most important plant source of the Brazilian green propolis. Since propolis is known for its antimicrobial activity, the aim of this work was to evaluate the antimicrobial activities of B. dracunculifolia and some of its isolated compounds. The results showed that the leaves extract of B. dracunculifolia (BdE) presents antifungal and antibacterial activities, especially against Candida krusei and Cryptococcus neoformans, for which the BdE showed IC50 values of 65 microg mL(-1) and 40 microg mL(-1), respectively. In comparison to the BdE, it was observed that the green propolis extract (GPE) showed better antimicrobial activity, displaying an IC50 value of 9 microg mL(-1) against C. krusei. Also, a phytochemical study of the BdE was carried out, affording the isolation of ursolic acid (1), 2a-hydroxy-ursolic acid (2), isosakuranetin (3), aromadendrin-4'-methylether (4), baccharin (5), viscidone (6), hautriwaic acid lactone (7), and the clerodane diterpene 8. This is the first time that the presence of compounds 1, 2, and 8 in B. dracunculifolia has been reported. Among the isolated compounds, 1 and 2 showed antibacterial activity against methicillin-resistant Staphylococcus aureus, displaying IC50 values of 5 microg mL(-1) and 3 microg mL(-1), respectively. 3 was active against C. neoformans, showing an IC50 value of 15 microg mL(-1) and a MIC value of 40 microg mL(-1), while compounds 4-8 were inactive against all tested microorganisms. The results showed that the BdE, similar to the GPE, displays antimicrobial activity, which may be related to the effect of several compounds present in the crude extract.  相似文献   

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