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1.
Inheritance pattern of wood traits viz. specific gravity, fibre dimensions and fibre-derived biometrical indices and their interactions among themselves and with that of growth are reported in Hevea brasiliensis. Girth (h2 =???0.02?±?0.44 to h2 =?0.35?±?0.24) showed moderate genetic control. Among wood traits, specific gravity (h2?=?0.15?±?0.31 to h2 =?0.33?±?0.28) was found to be under moderate genetic control. Fibre traits viz., fibre length (h2 =???0.26?±?0.30 to h2 =?0.50?±?0.34), fibre diameter (h2 =?0.19?±?0.49 to h2 =?0.70?±?0.11), fibre lumen diameter (h2 =???0.18?±?0.35 to h2 =?0.56?±?0.47) and fibre wall thickness (h2 =???5.17?±?5.26 to h2 =?0.50?±?0.50) were under moderate to strong genetic control. Among fibre-derived indices, flexibility coefficient (h2 =?0.48?±?0.21 to h2 =?0.89?±?0.29) showed moderate to very strong genetic control. The Runkel ratio (h2 =???0.40?±?0.27 to h2 =?0.42?±?0.29) and slenderness ratio (h2 =???0.36?±?0.29 to h2 =?0.43?±?0.28) showed moderate genetic control. Girth showed very strong positive genetic correlation with fibre wall thickness and strong positive correlation with fibre width indicating scope of indirect selection potential for these traits. Wood specific gravity was not correlated with either girth or fibre traits. Hence, it would be possible to concomitantly improve growth and fibre traits without adversely affecting wood specific gravity. Moderate to very high estimates of heritability for fibre traits, girth and specific gravity indicated that considerable genetic gain can be realised for these traits. Implications of the above findings in genetic improvement of wood in Hevea are discussed.  相似文献   

2.
Phycobiliproteins, light-harvesting pigments found in cyanobacteria and in some eukaryotic algae, have numerous commercial applications in food, cosmetic, and pharmaceutical industries. Colorant production from cyanobacteria offers advantages over their production from higher plants, as cyanobacteria have fast growth rate and high photosynthetic efficiency and require less space. In this study, three cyanobacteria strains were studied for phycobiliprotein production and the influence of sodium nitrate, potassium nitrate and ammonium chloride on the growth and phycobiliprotein composition of the strains were evaluated. In the batch culture period of 12 days, Phormidium sp. and Pseudoscillatoria sp. were able to utilize all tested nitrogen sources; however, ammonium chloride was the best nitrogen source for both strains to achieve maximum growth rate μ?=?0.284?±?0.03 and μ?=?0.274?±?0.13 day?1, chlorophyll a 16.2?±? 0.5 and 12.2?±? 0.2 mg L?1, and phycobiliprotein contents 19.38?±?0.09 and 19.99?±?0.14% of dry weight, whereas, for Arthrospira platensis, the highest growth rate of μ?=?0.304?±?0.0 day?1, chlorophyll a 19.1?±?0.5 mg L?1, and phycobiliprotein content of 22.27?±?0.21% of dry weight were achieved with sodium nitrate. The phycocyanin from the lyophilized cyanobacterial biomass was extracted using calcium chloride and food grade purity (A620/A280 ratio >?0.7) was achieved. Furthermore, phycocyanin was purified using two-step chromatographic method and the analytical grade purity (A620/A280 ratio >?4) was attained. SDS-PAGE demonstrated the purity and presence of two bands corresponding to α- and β-subunits of the C-phycocyanin. The results showed that Phormidium sp. and Pseudoscillatoria sp. could be good candidates for phycocyanin production.  相似文献   

3.
Studies with diterpenes from marine brown alga Canistrocarpus cervicornis showed the antiviral potential of the products from this alga in controlling the replication of HSV-1 and maintaining low cytotoxicity. Hence, the aim of this work was to evaluate the anti-herpetic efficacy of C. cervicornis extract ointment in BALB/c mice. To test the anti-herpetic efficacy in vivo, four groups of BALB/c mice (n?=?5) were used: 1—untreated, 2—extract ointment (2 % or 0.4 mg cm?2 dose?1), 3—Acyclovir cream (5 % or 1.0 mg cm?2 dose?1), and 4—ointment base. The right midflank of each mouse was clipped and depilated with a chemical depilatory. After 2 days, the skin area was scratched and inoculated with HSV-1. The ointments and cream were applied three times a day over a 16-day period, beginning 1 h after virus inoculation. The development of skin lesions was continuously monitored and scored. To evaluate the effect of C. cervicornis topical treatment on biochemical parameters and on body weight, two uninfected groups were formed: an untreated group and a group treated with ointment C. cervicornis extract (2 %). The signs of infection appeared from the second day after infection, while on the 10th day of the experiment, the ointment base and untreated groups had significantly more severe lesions than did the groups that were treated with extract (p?<?0.05) or acyclovir (p?<?0,01). The topical application of extract ointment did not change body weight, hepatic, or renal function suggesting that the extract has a low toxicity in this route of administration. These results suggest that the extract may be useful in reducing the severity of HSV-1 cutaneous lesions.  相似文献   

4.
The objective of this study comprises of developing novel co-spray dried rifampicin phospholipid lipospheres (SDRPL) to investigate its influence on rifampicin solubility and oral bioavailability. Solid-state techniques were employed to characterize the liposphere formulation. SDRPL solubility was determined in distilled water. BACTEC 460TB System was employed to evaluate SDRPL antimycobacterial activity. The oral bioavailability of the lipospheres was evaluated in Sprague Dawley rats. Lipospheres exhibited amorphous, smooth spherical morphology with a significant increase (p?<?0.001) in solubility of SDRPL (2:1), 350.9?±?23 versus 105.1?±?12 μg/ml and SDRPL (1:1) 306.4?±?20 versus 105.1?±?12 μg/ml in comparison to rifampicin (RMP). SDRPL exhibited enhanced activity against Mycobacterium tuberculosis, H37Rv strain, with over twofolds less minimum inhibitory concentration (MIC) than the free drug. Lipospheres exhibited higher peak plasma concentration (109.92?±?25 versus 54.31?±?18 μg/ml), faster T max (two versus four hours), and enhanced area under the curve (AUC0–∞) (406.92?±?18 versus 147.72?±?15 μg h/L) in comparison to pure RMP. Thus, SDRPL represents a promising carrier system exhibiting enhanced antimycobacterial activity and oral bioavailability of rifampicin.  相似文献   

5.
A Gram-stain negative, aerobic, motile by flagella, rod-shaped strain (THG-T16T) was isolated from rhizosphere of Hibiscus syriacus. Growth occurred at 10–40 °C (optimum 28–30 °C), at pH 6.0–8.0 (optimum 7.0) and at 0–1.0% NaCl (optimum 0%). Based on 16S rRNA gene sequence analysis, the near phylogenetic neighbours of strain THG-T16T were identified as Nibribacter koreensis KACC 16450T (98.6%), Rufibacter roseus KCTC 42217T (94.7%), Rufibacter immobilis CCTCC AB 2013351T (94.5%) and Rufibacter tibetensis CCTCC AB 208084T (94.4%). The DNA G+C content of strain THG-T16T was determined to be 46.7 mol%. DNA–DNA hybridization values between strain THG-T16T and N. koreensis KACC 16450T, R. roseus KCTC 42217T, R. immobilis CCTCC AB 2013351T, R.tibetensis CCTCC AB 208084T were 33.5?±?0.5% (31.7?±?0.7% reciprocal analysis), 28.1?±?0.2% (25.2?±?0.2%), 17.1?±?0.9% (10.2?±?0.6%) and 8.1?±?0.3% (5.2?±?0.1%). The polar lipids were identified as phosphatidylethanolamine, two unidentified aminophospholipids, an unidentified aminolipid and three unidentified lipids. The quinone was identified as MK-7 and the polyamine as sym-homospermidine. The major fatty acids were identified as C16:1 ω5c, C17:1 ω6c, iso-C15:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) and summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B). On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics, and DNA–DNA hybridization data, strain THG-T16T represents a novel species of the genus Nibribacter, for which the name Nibribacter flagellatus sp. nov. is proposed. The type strain is THG-T16T(=?KACC 19188T?=?CCTCC AB 2016246T).  相似文献   

6.
The purpose of this research was to prepare and characterize polyherbal patches made from polyvinyl alcohol (PVA) and hydroxypropylmethyl cellulose (HPMC) with glycerine as a plasticizer. Polyherbal extracts were Luk-Pra-Kob recipes extracted with 95% ethanol. They were prepared by mixing the polymer solutions and glycerine in a beaker; subsequently, the polyherbal extracts were homogeneously mixed. Then, they were transferred into a Petri dish and dried in a hot-air oven at 70?±?2°C for 5 h. The dry polyherbal patches were evaluated for physicochemical properties by Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and a scanning electron microscope. They were studied for in vitro release and skin permeation of the marker active compound (E)-4-(3′,4′-dimethoxyphenyl)but-3-en-l-ol (compound D) using a modified Franz-type diffusion cell. The polyherbal patches made from PVA as a matrix layer were homogeneous, smooth, and compact relative to HPMC-containing polyherbal patches. The selected polyherbal patches made from PVA produced a release profile with an initial burst effect in which compound D release was 74.21?±?6.13% within 8 h, but compound D could permeate the pig skin only 37.28?±?5.52% and was highly accumulated in newborn pig skin at 35.90?±?6.72%. The in vitro release and skin permeation kinetics of compound D were fitted to the Higuchi model. The polyherbal patches made from PVA could be suitably used for herbal medicine application.  相似文献   

7.
A Gram-stain negative, aerobic, motile, non-spore-forming and rod-shaped bacterial strain, designated YIM 730227T, was isolated from a soil sample, collected from Karak district, Khyber-Pakhtun-Khwa, Pakistan. The bacterium was characterized using a polyphasic taxonomic approach. Pairwise comparison of the 16S rRNA gene sequences showed that strain YIM 730227T is closely related to Phenylobacterium lituiforme FaiI3T (97.5% sequence similarity), Phenylobacterium muchangponense A8T (97.4%), Phenylobacterium panacis DCY109T (97.1%), Phenylobacterium immobile ET (97.1%) and Phenylobacterium composti 4T-6T (97.0%), while also sharing 98.0% sequence similarity with Phenylobacterium hankyongense HKS-05T after NCBI blast, showing it represents a member of the family Caulobacteraceae. The major respiratory quinone was Q-10 and the major fatty acids were C16:0, summed feature 8 (comprising C18:1ω7c and/or C18:1ω6c), C18:1ω7c 11-methyl and C17:0. The polar lipids were phosphatidylglycerol, unidentified glycolipids, phospholipid and unidentified lipid. The G?+?C content of the genomic DNA was 68.2 mol%. The DNA–DNA relatedness values of strain YIM 730227T with P. hankyongense HKS-05T, P. lituiforme FaiI3T, P. muchangponense A8T, P. panacis DCY109T, P. immobile ET and P. composti 4T-6T were 31.3?±?0.6, 26.1?±?0.2, 24.3?±?0.1, 21.8?±?0.9, 19.8?±?0.6 and 18.2?±?1.1%, respectively, values lower than 70%. Besides the morphological and chemotaxonomic characteristics, phylogenetic analyses of 16S rRNA gene sequences and the biochemical characteristics indicated that the strain YIM 730227T represents a novel member of the genus Phenylobacterium, for which the name Phenylobacterium terrae sp. nov. (type strain YIM 730227T =?KCTC62324T?=?CGMCC 1.16326T) is proposed.  相似文献   

8.
A Gram-stain positive, aerobic, non-motile, endospore-forming and rod-shaped strain (THG-NT9T) was isolated from a green tea sample. Growth occurred at 20–45 °C (optimum 28–35 °C), at pH 6.0–8.0 (optimum 7.0) and at 0–2.0% NaCl (optimum 0%). Based on 16S rRNA gene sequence analysis, the near phylogenetic neighbours of strain THG-NT9T were identified as Scopulibacillus daqui DSM 28236T (98.6%), Scopulibacillus darangshiensis DSM 19377T (97.4%), Pullulanibacillus pueri CGMCC 1.12777T (96.7%) and Pullulanibacillus camelliae CGMCC 1.15371T (96.3%). The DNA G?+?C content of strain THG-NT9T was determined to be 47.5 mol %. DNA–DNA hybridization values between strain THG-NT9T and S. daqui DSM 28236T, S. darangshiensis DSM 19377T, P. pueri CGMCC 1.12777T, P. camelliae CGMCC 1.15371T and Pullulanibacillus naganoensis DSM 10191T were 41.3?±?0.1 (39.4?±?0.4% reciprocal analysis), 39.1?±?0.1 (37.3?±?0.1%), 21.4?±?0.7 (20.1?±?0.3%), 20.7?±?0.1 (20.1?±?0.4%) and 12.1?±?0.2% (8.3?±?0.2%). The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids. The quinone was identified as MK-7. The major fatty acids were C18:3 ω7c, iso-C15:0, iso-C16:0, iso-C17:0 and anteiso-C17:0. The cell wall type was determined to be A1γ peptidoglycan with meso-diaminopimelic acid as the diagnostic diamino acid plus alanine and glutamic acid and glucose as the cell wall sugar. On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics, and DNA–DNA hybridization data, strain THG-NT9T represents a novel species of the genus Scopulibacillus, for which the name Scopulibacillus cellulosilyticus sp. nov. is proposed. The type strain is THG-NT9T (=?KCTC 33918T?=?CGMCC 1.16305T).  相似文献   

9.
This study examined the co-immobilization of the cyanobacterium Synechococcus elongatus with the plant growth-promoting bacterium Azospirillum brasilense in alginate beads and its potential application for the removal of phosphorus from aquaculture wastewater. Co-immobilization of both microorganisms significantly increased the cell density of S. elongatus (2852.5?×?104 cells mL?1) compared with that of immobilization of cyanobacteria alone (1325.2?×?104 cells mL?1). Chlorophyll a content was similar in co-immobilized (11.1?±?3.5 pg cell?1) and immobilized S. elongatus (14.5?±?4.9 pg cell?1). Azospirillum brasilense showed continuous growth until day 2, after which its cell concentration declined until the end of the assay. Co-immobilized S. elongatus removed more phosphorus (44.8 %) than immobilized cyanobacteria cells alone (32.0 %). In conclusion, phosphate removal was greater with free cells of S. elongatus but overlapped with the values that were obtained with the treatment of co-immobilization of cells. Our results demonstrate that A. brasilense enhances the growth of S. elongatus and improves its removal of phosphorus when they are co-immobilized in alginate beads compared with only immobilization of cyanobacteria cells alone.  相似文献   

10.
11.
The present work evaluated biomass productivity, carbon dioxide fixation rate, and biochemical composition of two microalgal species, Phaeodactylum tricornutum (Bacillariophyta) and Tetradesmus obliquus (Chlorophyta), cultivated indoors in high-technology photobioreactors (HT-PBR) and outdoors both in pilot ponds and low-technology photobioreactors in a greenhouse in southern Italy. Microalgae were grown in standard media, under nitrogen starvation, and in two liquid digestates obtained from anaerobic digestion of agro-zootechnical and vegetable biomass. P. tricornutum, cultivated in semi-continuous mode in indoor HT-PBRs with standard medium, showed a biomass productivity of 21.0?±?2.3 g m?2 d?1. Applying nitrogen starvation, the lipid productivity increased from 2.3 up to 4.5?±?0.5 g m?2 d?1, with a 24 % decrease of biomass productivity. For T. obliquus, a biomass productivity of 9.1?±?0.9 g m?2 d?1 in indoor HT-PBR was obtained using standard medium. Applying liquid digestates as fertilizers in open ponds, T. obliquus gave a biomass productivity (10.8?±?2.0 g m?2 d?1) not statistically different from complete medium such as P. tricornutum (6.5?±?2.2 g m?2 d?1). The biochemical data showed that the fatty acid composition of the microalgal biomass was affected by the different cultivation conditions for both microalgae. In conclusion, it was found that the microalgal productivity in standard medium was about doubled in HT-PBR compared to open ponds for P. tricornutum and was about 20 % higher for T. obliquus.  相似文献   

12.
This study aimed to overexpress a glucose oxidase gene (GOD1) in Aureobasidium sp. P6 to achieve Ca2+-gluconic acid (GA) overproduction. The GOD1 gene was cloned, deleted, and overexpressed. A protein deduced from the GOD1 gene of Aureobasidium sp. P6 strain had 1824 bp that encoded a protein with 606 amino acids, with a conserved NADB-ROSSMAN domain and a GMC-oxred domain. Deleting the GOD1 gene made the disruptant GOK1 completely lose the ability to produce GA and GOD1 activity, whereas overexpressing the GOD1 gene rendered the transformant GOEX8 to produce considerably more Ca2+-GA (160.5?±?5.6 g/L) and higher GOD1 activity (1438.6?±?73.2 U/mg of protein) than its parent P6 strain (118.7?±?4.3 g/L of Ca2+-GA and 1100.0?±?23.6 U/mg of GOD1 protein). During a 10-L fermentation, the transformant GOEX8 grown in the medium containing 160.0 g/L of glucose produced 186.8?±?6.0 g/L of Ca2+-GA, the yield was 1.2 g/g of glucose, and the volumetric productivity was 1.7 g/L/h. Most of the produced GOD1 were located in the yeast cell wall. The purified product was identified to be a GA. The transformant GOEX8 overexpressing the GOD1 gene could produce considerably more Ca2+-GA (186.8?±?6.0 g/L) than its wild-type strain P6.  相似文献   

13.
Horse heart carboxymethylated cytc (CM-cytc) displays myoglobin-like properties. Here, the effect of cardiolipin (CL) liposomes on the nitrite reductase activity of ferrous CM-cytc [CM-cytc-Fe(II)], in the presence of sodium dithionite, is reported between pH 5.5 and 7.6, at 20.0 °C. Cytc-Fe(II) displays a very low value of the apparent second-order rate constant for the NO2 ?-mediated conversion of cytc-Fe(II) to cytc-Fe(II)-NO [k on = (7.3 ± 0.7) × 10?2 M?1 s?1; at pH 7.4], whereas the value of k on for NO2 ? reduction by CM-cytc-Fe(II) is 1.1 ± 0.2 M?1 s?1 (at pH 7.4). CL facilitates the NO2 ?-mediated nitrosylation of CM-cytc-Fe(II) in a dose-dependent manner, the value of k on for the NO2 ?-mediated conversion of CL–CM-cytc-Fe(II) to CL–CM-cytc-Fe(II)-NO (5.6 ± 0.6 M?1 s?1; at pH 7.4) being slightly higher than that for the NO2 ?-mediated conversion of CL–cytc-Fe(II) to CL–cytc-Fe(II)-NO (2.6 ± 0.3 M?1 s?1; at pH 7.4). The apparent affinity of CL for CM-cytc-Fe(II) is essentially pH independent, the average value of B being (1.3 ± 0.3) × 10?6 M. In the absence and presence of CL liposomes, the nitrite reductase activity of CM-cytc-Fe(II) increases linearly on lowering pH and the values of the slope of the linear fittings of Log k on versus pH are ?1.05 ± 0.07 and ?1.03 ± 0.03, respectively, reflecting the involvement of one proton for the formation of the transient ferric form, NO, and OH?. These results indicate that Met80 carboxymethylation and CL binding cooperate in the stabilization of the highly reactive heme-Fe atom of CL–CM-cytc.  相似文献   

14.
The aim of this work was to evaluate the effects of co-inoculation with phosphate-solubilizing and nitrogen-fixing rhizobacteria on growth promotion, yield, and nutrient uptake by wheat. Out of twenty-five bacteria isolated from the rhizosphere soils of cereal, vegetable, and agro-forestry plants in eastern Uttar Pradesh, three superior most plant growth-promoting (PGP) isolates were characterized as Serratia marcescens, Microbacterium arborescens, and Enterobacter sp. based on their biochemical and 16S rDNA gene sequencing data and selected them for evaluating their PGP effects on growth and yield of wheat. Among them, Enterobacter sp. and M. arborescens fixed significantly higher amounts (9.32?±?0.57 and 8.89?±?0.58 mg Ng?1 carbon oxidized, respectively) of atmospheric nitrogen and produced higher amounts (27.06?±?1.70 and 26.82?±?1.63 TP 100 µg mL?1, respectively) of IAA in vitro compared to S. marcescens (8.32?±?0.39 mg Ng?1 carbon oxidized and 21.29?±?0.99 TP 100 µg mL?1). Although both M. arborescens and S. marcescens solubilized remarkable amounts of phosphate from tricalcium phosphate likely through production of organic acids, however, Enterobacter sp. was inactive. The effects of these three rhizobacteria were evaluated on wheat in alluvial soils of the Indo-Gangetic Plain by inoculation of plants with bacterial isolates either alone or in combinations in both pot and field conditions for two successive years. Rhizobacterial inoculation either alone or in consortium of varying combinations significantly (P?≤?0.05) increased growth and yield of wheat compared to mock inoculated controls. A consortium of two or three rhizobacterial isolates also significantly increased plant height, straw yield, grain yield, and test weight of wheat in both pot and field trials compared to single application of any of these isolates. Among the rhizobacterial treatment, co-inoculation of three rhizobacteria (Enterobacter, M. arborescens and S. marcescens) performed best in promotion of growth, yield, and nutrient (N, P, Cu, Zn, Mn, and Fe) uptake by wheat. Taken together, our results suggest that co-inoculation of Enterobacter with S. marcescens and M. arborescens could be used for preparation of an effective formulation of PGP consortium for eco-friendly and sustainable production of wheat.  相似文献   

15.
The aim of present study was to elucidate the association of CTLA4 +49 A/G and HLA-DRB1*/DQB1* gene polymorphism in south Indian T1DM patients. The patients and controls (n?=?196 each) were enrolled for CTLA4 and HLA-DRB1*/DQB1* genotyping by RFLP/PCR-SSP methods. The increased frequencies of CTLA4 ‘AG’ (OR?=?1.99; p?=?0.001), ‘GG’ (OR?=?3.94; p?=?0.001) genotypes, and ‘G’ allele (OR?=?2.42; p?=?9.26?×?10?8) were observed in patients. Reduced frequencies of ‘AA’ (OR?=?0.35; p?=?7.19?×?10?7) and ‘A’ (OR?=?0.41; p?=?9.26?×?10?8) in patients revealed protective association. Among HLA-DRB1*/DQB1* alleles, DRB1*04 (OR?=?3.29; p?=?1.0?×?10?5), DRB1*03 (OR?=?2.81; p?=?1.9?×?10?6), DQB1*02:01 (OR?=?2.93; p?=?1.65?×?10?5), DQB1*02:02 (OR?=?3.38; p?=?0.0003), and DQB1*03:02 (OR?=?7.72; p?=?0.0003) were in susceptible association. Decreased frequencies of alleles, DRB1*15 (OR?=?0.32; p?=?2.55?×?10?7), DRB1*10 (OR?=?0.45; p?=?0.002), DQB1*06:01 (OR?=?0.43; p?=?0.0001), and DQB1*05:02 (OR?=?0.28; p?=?2.1?×?10?4) in patients were suggested protective association. The combination of DRB1*03+AG (OR?=?5.21; p?=?1.4?×?10?6), DRB1*04+AG (OR?=?2.14; p?=?0.053), DRB1*04+GG (OR?=?5.21; p?=?0.036), DQB1*02:01+AG (OR?=?4.44; p?=?3.6?×?10?5), DQB1*02:02+AG (OR?=?20.9; p?=?9.5?×?10?4), and DQB1*02:02+GG (OR?=?4.06; p?=?0.036) revealed susceptible association. However, the combination of DRB1*10+AA (OR?=?0.35; p?=?0.003), DRB1*15+AA (OR?=?0.22; p?=?5.3?×?10?7), DQB1*05:01+AA (OR?=?0.45; p?=?0.007), DQB1*05:02+AA (OR?=?0.17; p?=?1.7?×?10?4), DQB1*06:01+AA (OR?=?0.40; p?=?0.002), and DQB1*06:02+AG (OR?=?0.34; p?=?0.001) showed decreased frequency in patients, suggesting protective association. In conclusion, CTLA4/HLA-DR/DQ genotypic combinations revealed strong susceptible/protective association toward T1DM in south India. A female preponderance in disease associations was also documented.  相似文献   

16.
An endophytic fungus (strain T1) isolated from Taxus baccata was studied for the production of metabolites with anticancer and antioxidant activities. This fungus was identified as Diaporthe sp. based on rDNA-internal transcribed spacer (ITS) sequence analysis. The crude extract showed cytotoxic activity against MCF-7 and HeLa cancer cell lines, with IC50 (concentration inhibiting 50% of growth rate) values of 1058?±?44 and 1257?±?80 μg ml?1, respectively. The scavenging activity of fungal extract increased significantly with increasing concentration [IC50 (concentration required to scavenge 50% of free radicals) 482?±?9 μg ml?1]. Ultra-high-performance liquid chromatography-quadrupole-time of flight analysis revealed the presence of three trichalasins (trichalasin E, F and H) in the crude extract of T1 which are known to have antitumour and antioxidant activities. These results suggest that Diaporthe sp. has the potential to be used for therapeutic purposes because of its antiproliferative and antioxidant potential and also for the production of cytochalasins.  相似文献   

17.
The filamentous Cyanobacterium Arthrospira is commercially produced and is a functional, high-value, health food. We identified 5 low temperature and low light intensity tolerant strains of Arthrospira sp. (GMPA1, GMPA7, GMPB1, GMPC1, and GMPC3) using ethyl methanesulfonate mutagenesis and low temperature screening. The 5 Arthrospira strains grew rapidly below 14?°C, 43.75 μmol photons m?2 s?1 and performed breed conservation at 2.5?°C, 8.75 μmol photons m?2 s?1. We used morphological identification and molecular genetic analysis to identify GMPA1, GMPA7, GMPB1 and GMPC1 as Arthrospira platensis, while GMPC3 was identified as Arthrospira maxima. Growth at different culture temperatures was determined at regular intervals using dry biomass. At 16?°C and 43.75 μmol photons m?2 s?1, the maximum dry biomass production and the mean dry biomass productivity of GMPA1, GMPB1, and GMPC1 were 2057?±?80 mg l?1, 68.7?±?2.5 mg l?1 day?1, 1839?±?44 mg l?1, 60.6?±?1.8 mg l?1 day?1, and 2113?±?64 mg l?1, 77.7?±?2.5 mg l?1 day?1 respectively. GMPB1 was chosen for additional low temperature tolerance studies and growth temperature preference. In winter, GMPB1 grew well at mean temperatures <10?°C, achieving 3258 mg dry biomass from a starting 68 mg. In summer, GMPB1 grew rapidly at mean temperatures more than 28?°C, achieving 1140 mg l?1 dry biomass from a starting 240 mg. Phytonutrient analysis of GMPB1 showed high levels of C-phycocyanin and carotenoids. Arthrospira metabolism relates to terpenoids, and the methyl-d-erythritol 4-phosphate pathway is the only terpenoid biosynthetic pathway in Cyanobacteria. The 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) gene from GMPB1 was cloned and phylogenetic analysis showed that GMPB1 is closest to the Cyanobacterium Oscillatoria nigro-viridis PCC711. Low temperature tolerant Arthrospira strains could broaden the areas suitable for cultivation, extend the seasonal cultivation time, and lower production costs.  相似文献   

18.
Hypoaspis larvicolus (Acari: Laelapidae) (first report from Turkey) occurred together with Sancassania polyphyllae (Acari: Acaridae) on the larvae of the scarab beetle, Polyphylla fullo (Coleoptera: Scarabaeidae), that were feeding on the roots of strawberry in Aydin, Turkey. Laboratory studies were conducted to (1) observe whether H. larvicolus feeds and completes its life cycle on the various stages of S. polyphyllae or other astigmatid mites, such as Acarus siro, Carpoglyphus lactis and Tyrophagus putrescentiae (Acaridae), and to determine its population growth when feeding on these prey, and (2) to determine development periods, longevity and fecundity of H. larvicolus feeding on C. lactis. Hypoaspis larvicolus females did not feed on S. polyphyllae, but fed, developed and reproduced when A. siro, C. lactis or T. putrescentiae were provided as prey. Hypoaspis larvicolus is larviparous as well as oviparous. The female lays eggs or gives birth to larvae. If a female gives birth to a larva, it is attached under the female’s venter for 1–2 days, a phenomenon recorded for the first time in Hypoaspis; in fact, for the first time in mites. The results of the population growth experiments revealed that H. larvicolus feeding on C. lactis produced the highest number of eggs, juveniles and adults. The developmental periods of H. larvicolus feeding on C. lactis at life-cycle path I (larva to adult) and II (egg to adult) were 12.2?±?0.3 and 15.6?±?0.6 days (females) and 19.5?±?0.2 and 20.9?±?0.4 days (males), respectively. Longevity of females versus males of H. larvicolus was 120.6?±?7.2 versus 91.6?±?13.1 days (life cycle I) and 110.0?±?27.7 versus 118.3?±?10.9 days (life cycle II), respectively.  相似文献   

19.

Background

Male European seabass, already predominant (~?70%) in cultured stocks, show a high incidence (20–30%) of precocious sexual maturation under current aquaculture practices, leading to important economic losses for the industry. In view of the known modulation of reproductive development by swimming exercise in other teleost species, we aimed at investigating the effects of sustained swimming on reproductive development in seabass males during the first year of life in order to determine if swimming could potentially reduce precocious sexual maturation.

Methods

Pre-pubertal seabass (3.91?±?0.22 g of body weight (BW)) were subjected to a 10 week swimming regime at their optimal swimming speed (Uopt) in an oval-shaped Brett-type flume or kept at rest during this period. Using Blazka-type swim tunnels, Uopt was determined three times during the course of the experiment: 0.66 m s??1 at 19?±?1 g BW, 10.2?±?0.2 cm of standard length (SL) (week 1); 0.69 m s??1 at 38?±?3 g BW, 12.7?±?0.3 cm SL (week 5), and also 0.69 m s??1 at 77?±?7 g BW, 15.7?±?0.5 cm SL (week 9). Every 2 weeks, size and gonadal weight were monitored in the exercised (N?=?15) and non-exercised fish (N?=?15). After 10 weeks, exercised and non-exercised males were sampled to determine plasma 11-ketotestosterone levels, testicular mRNA expression levels of genes involved in steroidogenesis and gametogenesis by qPCR, as well as the relative abundance of germ cells representing the different spermatogenic stages by histological examination.

Results

Our results indicate that sustained swimming exercise at Uopt delays testicular development in male European seabass as evidenced by decreased gonado-somatic index, slower progression of testicular development and by reduced mRNA expression levels of follicle stimulating hormone receptor (fshR), 3-beta-hydroxysteroid dehydrogenase (3βhsd), 11-beta hydroxysteroid dehydrogenase (11βhsd), estrogen receptor-beta (erβ2), anti-mullerian hormone (amh), structural maintenance of chromosomes protein 1B (smc1β), inhibin beta A (inhba) and gonado-somal derived factor 1 (gsdf1) in exercised males as compared with the non-exercised males.

Conclusions

Swimming exercise may represent a natural and non-invasive tool to reduce the incidence of sexually precocious males in seabass aquaculture.
  相似文献   

20.
A Nocardia-like actinobacterial strain, designated YIM TG2190T, was isolated from rhizosphere soil of Psammosilene tunicoides collected from Gejiu, Yunnan province, China. The cells of strain YIM TG2190T were observed to be Gram-stain positive and non-motile. The strain forms extensively branched substrate mycelia that fragments into rod-shaped elements. The 16S rRNA gene sequence analysis showed that strain YIM TG2190T is closely related to Nocardia nova (97.5%), Nocardia jiangxiensis (97.1%) and Nocardia miyunensis (96.8%). Growth occurs at 4–30?°C (optimum 28?°C), pH 6.0–8.0 (optimum pH 7.0) and the strain can tolerate NaCl (w/v) up to 3% (optimum 0–1%). The cell walls were found to contain meso-diaminopimelic acid. The whole-cell sugars were identified as glucose, mannose, ribose, galactose, arabinose and fucose. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannosides, phosphatidylglycerol and an unidentified phospholipid. The menaquinones detected were MK-9 (H2) and MK-8 (H4). The major fatty acids (>?5%) were found to be C16:0 (33.9%), summed feature 3 (21.7%), C18:0 10-methyl TBSA (13.7%) and C18:1ω9c (7.0%). The DNA G+C content was determined to be 61.1 mol%. DNA-DNA relatedness between the strain YIM TG2190T and N. nova CGMCC 4.1705T, N. jiangxiensis CGMCC 4.1905T and N. miyunensis CGMCC 4.1904T were 46.9?±?2.6, 36.8?±?1.3, and 35.7?±?2.6%, respectively, values which are less than the threshold value (70%) for the delineation of prokaryotic genomic species. The phenotypic, chemotaxonomic and phylogenetic data indicates that strain YIM TG2190T represents a novel species of the genus Nocardia, for which the name Nocardia zhihengii sp. nov. is proposed. The type strain is YIM TG2190T (=KCTC 39596T?=?DSM 100515T).  相似文献   

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