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1.
Free sterol fractions were isolated from the marine sponges Phyllospongia madagascarensis, Scalarispongia sp., Oceanapia sp., Monanchora clathrata and studied by GLC, GLC–MS, and spectroscopy NMR. P. madagascarensis and Scalarispongia sp. contained common Δ5-sterols; cholesterol was shown to be a main sterol of both the sponges. Oceanapia sp. contained stanols and minor Δ5-sterols with 24R-24,25-methylene-5α-cholestan-3β-ol as a main constituent. Many free sterols from M. clathrata were Δ7-series compounds, and latosterol was a main sterol. Δ4-3-Ketosteroids and Δ5-sterol esters were found in the Antarctic sponge Haliclona sp., but free sterols were practically absent except for trace amount of cholesterol. A chemotaxonomic application of sterols in relation to the genera Phyllospongia, Oceanapia and the family Crambeidae is provided. The known cases of the absence of sterols in sponges and probable reasons of the phenomenon are discussed.  相似文献   

2.
Actinobacteria exclusively within the sub-class Acidimicrobidae were shown by 16S rDNA community analysis to be major components of the bacterial community associated with two sponge species in the genus Xestospongia. Four groups of Actinobacteria were identified in Xestospongia spp., with three of these four groups being found in both Xestospongia muta from Key Largo, Florida and Xestospongia testudinaria from Manado, Indonesia. This suggests that these groups are true symbionts in these sponges and may play a common role in both the Pacific and Atlantic sponge species. The fourth group was found only in X. testudinaria and was a novel assemblage distantly related to any previously sequenced actinobacterial clones. The only actinobacteria that were obtained in initial culturing attempts were Gordonia, Micrococcus and Brachybacterium spp., none of which were represented in the clone libraries. The closest cultured actinobacteria to all the Acidimicrobidae clones from Xestospongia spp. are Microthrix parvicella and Acidimicrobium spp. Xestospongia spp. can now be targeted as source material from which to culture novel Acidimicrobidae to investigate their potential as producers of bioactive compounds. Isolation of sponge-associated Acidimicrobidae will also make it possible to elucidate their role as sponge symbionts.  相似文献   

3.
Two halophilic archaea, strains MDB25(T) and MDB20, were isolated from a sample of the brine from Lake Medee, at a depth of 3050m, in the Mediterranean Sea. Cells of the organisms were Gram-negative, non-motile and pleomorphic, and colonies were red pigmented. Strains MDB25(T) and MDB20 showed optimum growth at 45°C, in 2.6-3.4M NaCl and at pH 7.0-8.0. The major polar lipids of the two strains were phosphatidylglycerol (PG1 and PG2), phosphatidylglycerol phosphate methyl ester (PGP-Me) and mannose-2,6-dissulfate (1→2)-glucose glycerol diether (S(2)-DGD). Menaquinone MK-8 and MK-8(H(2)) were the major respiratory quinones. The DNA G+C content of strain MDB25(T) was 63.0%. The strains were facultatively anaerobic but grew better under aerobic conditions, nitrate served as electron acceptor. Analysis of the almost complete 16S rRNA gene sequence indicated that the strains MDB25(T) and MDB20 represented a member of the genus Natrinema in the family Halobacteriaceae. Both strains formed a distinct cluster and were most closely related to Natrinema ejinorense JCM 13890(T) and Haloterrigena longa JCM 13562(T) (98.0% and 97.9% sequence similarity, respectively). Based on 16S rRNA gene sequence analysis, DNA-DNA hybridization results, physiological and biochemical characteristics we describe a new species represented by strain MDB25(T) (=DSM 25055(T) =JCM 17869(T)) for which we propose the name Natrinema salaciae sp. nov.  相似文献   

4.
Marine sponges are a rich source of structurally and biologically active metabolites of biomedical importance. We screened polar and non-polar samples of crude extracts obtained from marine sponges collected in different locations of Argentinean south sea coast, as a novel approach for their characterization.The evaluation was performed using cytotoxic and genotoxic biomarkers such as mitotic index (MI), cell proliferation kinetics (CPK) and sister chromatid exchanges (SCE), monitored in vitro using peripheral blood lymphocytes. Statistical analysis was performed using two-way analysis of variance (ANOVA). The extracts evaluated belonged to: Callyspongia flabellata (BURTON, 1932) (Callyspongiidae); Plicatellopsis sp.(Suberitidae); Callyspongia fortis (RIDLEY, 1881) (Callyspongiidae); Clathria (Microciona) antarctica (TOPSENT, 1917) (Microcionidae); Spongia (Spongia) magellanica (THIELE, 1905) (Spongiidae); Halicnemia papillosa (THIELE, 1905) (Axinellidae); Cliona chilensis (THIELE, 1905) (Clionidae); Haliclona sp. 1; Haliclona sp. 2(Chalinidae).Genotoxicity studies revealed that the evaluated sponge extracts did not exhibit cytotoxic activity measured from mitotic index MI and cell proliferation kinetics(CPK). In contrast, sister chromatid exchanges (SCE) showed that the non-polar extract of Callyspongia fortis and the polar extract of Cliona chilensis presented significant differences in SCE frequency (p < 0.001), when compared with control cultures. These results emphasize the need to set up a standard battery of “in vitro” genotoxicity testing for new chemicals, pharmaceutical and drugs.  相似文献   

5.
The paper reports the isolation and structural elucidation of seven diketopiperazines from the title microorganisms. Although all isolates are known, three of which were isolated from the actinomycetes for the first time. And this is also the first report to isolate four DKPs from the D. avara-associated microorganism.  相似文献   

6.
In this paper, we report the synthesis and bioactivity of four synthetic analogues of 28-homobrassinosteroids, in order to evaluate the influence in bioactivity when the C-6 keto group is replaced by different functional groups. The synthetic analogues are 6-deoxo-28-homocastasterone [(22R,23R)-stigmasta-2alpha,3alpha,22,23-tetraol], 6alpha-hydroxy-28-homocastasterone [(22R,23R)-stigmasta-2alpha,3alpha,6alpha,22,23-pentaol], 6beta-hydroxy-28-homocastasterone [(22R,23R)-stigmasta-2alpha,3alpha,6beta,22,23-pentaol], and [(22R,23R)-6alpha-fluorostigmasta-2alpha,3alpha,22,23-tetraol]. Results indicate that replacement of the 6-keto moiety by an beta or alpha hydroxyl group led to a decrease in activity, whereas the 6-deoxo analogue showed a very low activity, confirming the importance of an electronegative moiety at C-6 to observe hormonal potency. The 6alpha-fluorinated analogue elicited a low activity, similar to that of the 6-deoxo analogue.  相似文献   

7.
The sterol composition of two sponges, Haliclona flavescens and Haliclona cinerea, from the Black Sea was investigated. Sterol composition in the two species is similar and both sponges actively transform dietary sterols into stanols and further to Δ7-sterols. Short side chain sterols of androstane and pregnane type were discovered in one sample. The composition of steryl esters and the taxonomic position of the two Haliclona species are discussed.  相似文献   

8.
Major glycolipids [monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfoquinovosyldiacylglycerol (SQDG)) and phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG)] as well as betaine lipid 1,2-diacylglycero-O-4'-(N,N,N-tri-methyl)-homoserine (DGTS) were isolated from Anfeltia tobuchiensis (Rhodophyta), Laminaria japonica, Sargassum pallidum (Phaeophyta), Ulva fenestrata (Chlorophyta) and Zostera marina (Embriophyta), harvested in the Sea of Japan. GC analysis of their fatty acid (FA) composition revealed that the n-6 polyunsaturated FAs (PUFAs) shared the most part of the sum of n-6 and n-3 PUFAs in PC and PE compared with glycolipids and PG. In algae, it was related to the prevalence of 20:4n-6 over 20:5n-3 in non-photosynthetic lipids. Percentage of n-6 PUFAs as well as the sum of n-3 and n-6 PUFAs decreased in the following sequence: PC-->PE-->PG. The saturation increased in the lines of MGDG-->DGDG-->SQDG and PC-->PE-->PG. PG was close to SQDG by the level of saturation. Distribution of C(18) and C(20) PUFAs in polar lipids depended on taxonomic position of macrophytes. Balance between C(18) and C(20) PUFAs was preferably shifted to the side of C(20) PUFAs in PC and PE that was observed in contrast to glycolipids and PG from L. japonica containing both series of FAs. The set of major FAs of polar lipid classes can essentially differ from each other and from total lipids of macrophytes. For example, MGDG was found to accumulate characteristic fatty acids 16:4n-3, 16:3n-3, 18:3n-6 and 18:4n-3, 20:3n-6 in U. fenestrata, Z. marina, L. japonica and S. pallidum, respectively.  相似文献   

9.
10.
An alternative approach for plant complex protein extracts pre-purification by in-solution isoelectric focusing in non-denaturing conditions is presented. The separation of biologically active proteins, in narrow ranges of isoelectric point (pI) was obtained by a modified OFFGEL electrophoresis. Two different water-soluble protein extracts from Phragmites leaves were fractionated into 24 fractions within a 3–10 pI range at 10 °C in the absence of denaturing/reducing agents. One-dimensional electrophoretic analysis revealed different protein distribution patterns and the effective fractionation of both protein extracts. Peroxidase activity of each fraction confirmed that proteins remained active and pre-purification occurred. Biological triplicates assured the needed reproducibility.  相似文献   

11.
为探明爵床(Justicia procumbens)甲醇提取物对小菜蛾的生物活性,采用室内生测法测定了爵床甲醇提取物对小菜蛾的触杀、拒食、胃毒、生长发育抑制和产卵忌避作用。结果表明,爵床甲醇提取物对小菜蛾幼虫具有较强的触杀、拒食、胃毒和生长发育抑制活性,对小菜蛾成虫具有较强的产卵忌避活性。在触杀试验中,药后1、2 d和3 d爵床甲醇提取物对小菜蛾3龄幼虫的致死中浓度(LC50)分别为5.17、4.05和3.06 mg/m L;在拒食试验中,药后1 d和2 d提取物对3龄幼虫的选择性拒食中浓度(AFC50)分别为2.64和3.13 mg/m L,药后1 d和2 d提取物对3龄幼虫的非选择性拒食中浓度(AFC50)分别为3.70、4.54 mg/m L;在胃毒试验中,药后4、5、6 d和7 d提取物对3龄幼虫的致死中浓度(LC50)分别为8.13、3.65、2.88、2.23 mg/m L;在生长发育抑制试验中,药后1 d和2 d提取物对3龄幼虫的抑制中浓度(IC50)分别为2.02、1.40 mg/m L;在产卵忌避试验中,药后1、2 d和3 d提取物对小菜蛾成虫的选择性产卵忌避中浓度(AOC50)分别为2.61、3.66、4.58 mg/m L,药后1、2和3 d提取物对小菜蛾成虫的非选择性产卵忌避中浓度(AOC50)分别为3.19、4.52、5.65 mg/m L。由此证实,爵床提取物对小菜蛾具有显著的毒杀活性,具有开发为新型高效、低毒植物源农药的潜在价值。  相似文献   

12.
A Gram-positive, coccoid bacterial isolate (02-St-019/1T), forming beige pigmented colonies was obtained from an indoor air sample. Based on 16S rRNA gene sequence similarity studies it was determined that this isolate 02-St-019/1T belonged to the genus Kytococcus, showing sequence similarties of 98.6% to Kytococcus schroeteri DSM 13884T and 98.3% to Kytococcus sedentarius DSM 20547T, respectively. The diagnostic diaminoacid of the peptidoglycan was lysine, cell wall sugars were ribose and xylose. The major menaquinones detected were MK-7 and MK-8. The polar lipid profile consisted of the major phospholipids diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylserine and phosphatidylinositol mannoside. Fatty acid patterns were composed of major amounts of the iso- and anteiso-branched fatty acids anteiso C17:0, iso C15:0 and iso C17:0 and unsaturated fatty acids (C17:1 ω8c, iso C17:1 ω9c, and C17:1 ω8c) with smaller amounts of the straight-chain fatty acids C15:0, C16:0 and C17:0. The results of DNA–DNA hybridizations and physiological and biochemical tests clearly allowed a genotypic and phenotypic differentiation of strain 02-St-019/1T from the two described Kytococcus species. On the basis of these results a novel species to be named Kytococcus aerolatus sp. nov., is proposed, with the type strain 02-St-019/1T (=DSM 22179T=CCM 7639T).  相似文献   

13.
Two extremely halophilic archaeal strains GX3(T) and GX26(T) were isolated from the Gangxi marine solar saltern near the Weihai city of Shandong Province, China. Cells from the two strains were pleomorphic and stained Gram-negative, colonies were red-pigmented. Strains GX3(T) and GX26(T) were able to grow at 25-50 °C (optimum 37 °C), at 1.4-5.1M NaCl (optimum 3.1M), at pH 5.5-9.5 (optimum pH 7.0) and neither strain required Mg(2+) for growth. Cells lyse in distilled water and the minimal NaCl concentration to prevent cell-lysis was 8% (w/v). The major polar lipids of the two strains were PA (phosphatidic acid), PG (phosphatidylglycerol), PGP-Me (phosphatidylglycerol phosphate methyl ester) and three major glycolipids (GL1, GL2 & GL3) chromatographically identical to S-TGD-1 (sulfated galactosyl mannosy glucosyl diether), S-DGD-1 (sulfated mannosyl glucosyl diether), and DGD-1 (mannosyl glucosyl diether) respectively, an unidentified lipid (GL4) was also detected in strain GX26(T). Phylogenetic analysis based on 16S rRNA gene revealed that strain GX3(T) and strain GX26(T) formed a distinct clade with the closest relative, Haladaptatus paucihalophilus (89.9-92.4% and 90.4-92.7, respectively). The rpoB' gene similarities between strains GX3(T) and GX26(T), and between the two strains and the closest relative, Halorussus rarus TBN4(T) are 96.5%, 84.3% and 83.9%, respectively. The DNA G+C contents of strain GX3(T) and strain GX26(T) are 67.3 mol% and 67.2 mol%, respectively. The DNA-DNA hybridization value between strain GX3(T) and strain GX26(T) was 44%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain GX3(T) and strain GX26(T) represent two novel species in a new genus within the family Halobacteriaceae, Halorubellus salinus gen. nov., sp. nov. (type strain GX3(T)=CGMCC 1.10384(T)=JCM 17115(T)) and Halorubellus litoreus sp. nov. (type strain GX26(T)=CGMCC 1.10386(T)=JCM 17117(T)).  相似文献   

14.
Sun L  Song Y  Qu Y  Yu X  Zhang W 《Cell and tissue research》2007,328(1):223-237
Marine sponges (Porifera) are the best source of marine bioactive metabolites for drug discovery and development, although the sustainable production of most sponge-derived metabolites remains a difficult task. In vitro cultivation of sponge cells in bioreactors has been proposed as a promising technology. However, no continuous cell line has as yet been developed. Archaeocytes are considered to be toti/multipotent stem cells in sponges and, when purified, may allow the development of continuous sponge cell lines. As a prerequisite, we have developed a novel four-step protocol for the purification of archaeocytes from a marine sponge, Hymeniacidon perleve: (1) differential centrifugation to separate large sponge cells including archaeocytes; (2) selective agglomeration in low-Ca2+/Mg2+ artificial seawater in which living archaeocytes form small loose aggregates with some pinacocytes and collencytes; (3) differential adherence to remove anchorage-dependent pinacocytes, collencytes and other mesohyl cells; (4) Ficoll-Vrografin density gradient centrifugation to purify archaeocytes. The final purity of archaeocytes is greater than 80%. The proliferation potential of the archaeocytes has been demonstrated by high levels of BrdU incorporation, PCNA expression and telomerase activity. In 4-day primary cultures, the purified archaeocytes show a 2.5-fold increase in total cell number. This study opens an important avenue towards developing sponge cell cultures for the commercial exploitation of sponge-derived drugs. The authors are grateful for the financial support of the Chinese Academy of Sciences under the “100 Talent Project”, the “Innovation Fund” from the Dalian Institute of Chemical Physics, the “Hi-Tech Research and Development Program of China” (2001AA620404), and the European Commission (project: Silicon Biotechnology).  相似文献   

15.
Major glyco- and phospholipids as well as betaine lipid 1,2-diacylglycero-O-4'-(N,N,N-tri-methyl)-homoserine (DGTS) were isolated from five species of marine macrophytes harvested in the Sea of Japan in summer and winter at seawater temperatures of 20-23 and 3 degrees C, respectively. GC and DSC analysis of lipids revealed a common increase of ratio between n-3 and n-6 polyunsaturated fatty acids (PUFAs) of polar lipids from summer to winter despite their chemotaxonomically different fatty acid (FA) composition. Especially, high level of different n-3 PUFAs was observed in galactolipids in winter. However, the rise in FA unsaturation did not result in the lowering of peak maximum temperature of phase transition of photosynthetic lipids (glycolipids and phosphatidylglycerol (PG)) in contrast to non-photosynthetic ones [phosphatidylcholine (PC) and phosphatidylethanolamine (PE)]. Different thermotropic behavior of these lipid groups was accompanied by higher content of n-6 PUFAs from the sum of n-6 and n-3 PUFAs in PC and PE compared with glycolipids and PG in both seasons. Seasonal changes of DSC transitions and FA composition of DGTS studied for the first time were similar to PC and PE. Thermograms of all polar lipids were characterized by complex profiles and located in a wide temperature range between -130 and 80 degrees C, while the most evident phase separation occurred in PGs in both seasons. Polarizing microscopy combined with DSC has shown that the liquid crystal - isotropic melt transitions of polar lipids from marine macrophytes began from 10 to 30 degrees C mostly, which can cause the thermal sensitivity of plants to superoptimal temperatures in their environment.  相似文献   

16.
Benthic marine invertebrates collected from sub-Arctic regions of northern Norway, were found to be a promising source of novel bioactive compounds against human and fish pathogenic bacteria and fungi. Lyophilized material from seven species of ascidians, six sponges and one soft alcyonid coral were extracted with 60% acidified acetonitrile (ACN). After separation into an ACN-rich phase (ACN-extract) and an aqueous phase, and subsequent solid-phase extraction of the aqueous phase, fractions differing in polarity were obtained and screened for antibacterial and antifungal activities, along with the more lipophilic ACN-extracts. Antimicrobial activity was determined against two Gram-negative, two Gram-positive bacteria, and two strains of fungi. Notably, all the invertebrate species in the study showed activity against all four strains of bacteria and the two strains of fungi. In general, the aqueous fractions displayed highest antimicrobial activity, and the most potent extracts were obtained from the colonial ascidian Synoicum pulmonaria which displayed activity against bacteria and fungi at a concentration of 0.02 mg/ml; the lowest concentration tested.  相似文献   

17.
Species distribution of staphylococci from small wild mammals   总被引:1,自引:0,他引:1  
A total of 197 isolates of Staphylococcus from small wild animals (insectivores and rodents) were identified by partial sequencing of the rpoB and dnaJ genes. Among the identified isolates the predominant species was S. succinus (28%), followed by S. xylosus (20.8%) and S. stepanovicii (18.3%). The other 14 Staphylococcus species were occasionally isolated. PCR-RFLP of the rpoB gene digested by Hpy8I was a fast and simple method to distinguish the two subspecies of S. succinus. More than 90% of the 55 S. succinus strains isolated belonged to S. succinus subsp. casei and only 9% to S. succinus subsp. succinus. Moreover, the present study describes the first ever isolation of S. fleurettii from healthy animals.  相似文献   

18.
Five isolates from marine fish (W3T, WM, W1S, S2 and S3) and three isolates misclassified as Photobacterium phosphoreum, originating from spoiled modified atmosphere packed stored cod (NCIMB 13482 and NCIMB 13483) and the intestine of skate (NCIMB 192), were subjected to a polyphasic taxonomic study. Phylogenetic analysis of 16S rRNA gene sequences showed that the isolates were members of the genus Photobacterium. Sequence analysis using the gapA, gyrB, pyrH, recA and rpoA loci showed that these isolates formed a distinct branch in the genus Photobacterium, and were most closely related to Photobacterium aquimaris, Photobacterium kishitanii, Photobacterium phosphoreum and Photobacterium iliopiscarium. The luxA gene was present in isolates W3T, WM, W1S, S2 and S3 but not in NCIMB 13482, NCIMB 13483 and NCIMB 192. AFLP and (GTG)5-PCR fingerprinting indicated that the eight isolates represented at least five distinct genotypes. DNA–DNA hybridizations revealed 89% relatedness between isolate W3T and NCIMB 192, and values below 70% with the type strains of the phylogenetically closest species, P. iliopiscarium LMG 19543T, P. kishitanii LMG 23890T, P. aquimaris LMG 26951T and P. phosphoreum LMG4233T. The strains of this new taxon could also be distinguished from the latter species by phenotypic characteristics. Therefore, we propose to classify this new taxon as Photobacterium piscicola sp. nov., with W3T (=NCCB 100098T = LMG 27681T) as the type strain.  相似文献   

19.
Procyanidin oligomers in Cinnamon are thought to be responsible for the biological activity in the treatment of diabetes mellitus (DM). To clarify types of procyanidin oligomers in different Cinnamon species and investigate their different effects, the present study investigated procyanidin oligomers in polyphenolic oligomer-rich extracts of three Cinnamon samples by LC-MS methods, and their hypoglycemic activities were detected in vivo and in vitro. The results showed that two of the three samples from Cinnamomum cassia were rich in B-type procyanidin oligomers, and the other sample was rich in A-type procyanidin oligomers. The Cinnamon extracts were administered at doses of 200 and 300 mg/kg body wt. in high-fat diet-fed and low-dose streptozotocin (STZ)-induced diabetic mice for 14 days. The results showed that blood glucose concentrations were significantly decreased in all Cinnamon extract groups compared with the control group (p < 0.05). Administration of the Cinnamon extracts significantly increased the consumption of extracellular glucose in insulin-resistant HepG2 cells and normal HepG2 cells compared with the control group. These results suggest that both A- and B-type procyanidin oligomers in different Cinnamon species have hypoglycemic activities and may improve insulin sensitivity in type 2 DM.  相似文献   

20.
An intense colored marine bacterium, identified as Cellulophaga lytica, was isolated previously from a sea anemone surface on the Charente-Maritime rocky shore (Atlantic Coast, France), and iridescence of its colonies under direct light was recently described. In addition, iridescence intensities were found to differ strongly between C. lytica strains from different culture collections. However, importantly, the occurrence and distribution of iridescent bacteria in the marine environment were still unknown. Therefore, in this study, a search was undertaken for marine iridescent bacterial strains in different biotopes of the Charente-Maritime coast. Various marine samples (water, sediment, macroalgae, other macroorganisms and detritus) were collected from seven biotopes using a direct plate inoculation method. As a result, 34 iridescent strains related to the genus Cellulophaga, as well as 63 iridescent strains affiliated to the genera Tenacibaculum and Aquimarina, were isolated. Iridescent colors were different according to the genera but iridescent marine bacteria were widely distributed. However, a majority of strains were isolated from rocky shores and, in particular, red seaweed surfaces and mollusks. The data from the study suggested that isolates with iridescent properties were well conserved in stressful environments such as the coastal shoreline. This origin may provide an insight into the ecological and biological functions of iridescence.  相似文献   

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