共查询到20条相似文献,搜索用时 15 毫秒
1.
Indu Chaturvedi Tapas Kumar Dutta Pawan Kumar Singh Ashwani Sharma 《Bioinformation》2015,11(5):261-266
The present study was to evaluate effect of herbal feed additives on methane and total gas production during the rumen
fermentation for environment and animal health concern. Different parts of the five medicinal plants were selected such as leaf and
small stems of Ocimum sanctum (Tulsi), roots of Curcuma longa (Haldi), fruits of Emblica officinalis (Amla), leaves of Azadirachta
indica (Neem) and leaves and small stem of Clerodendrum phlomidis (Arni) for our study. Addition of different herbal additive
combinations did not influence IVDMD and total gas production however methane production (mg/g of substrate DM) was
significantly (P<0.05) reduced in Amla: Neem and Neem: Arni combinations. Total nitrogen significantly (P<0.01) increased in the
combinations of Tulsi: Haldi and Amla: Neem. TCA–ppt-N is significantly (P<0.01) increased in Tulsi: Haldi, Haldi: Amla, Amla:
Neem and Neem: Arni however NH3-N (mg/dl) significantly decreased in all treatments. We conclude that the screening of plant
combinations, Amla: Neem and Neem: Arni have potential to decrease methane production and our herbal feed supplements have
no side-effects on the ruminant in small amount. 相似文献
2.
Helmut Dietrich Wolfgang Maret Henryk Kozkłowski Michael Zeppezauer 《Journal of inorganic biochemistry》1981,14(4):297-311
Insertion of nickel ions into the empty catalytic site of horse liver alcohol dehydrogenase yields an active enzyme with 65% metal substitution and about 12% intrinsic activity. The electronic absorption spectrum is characterized by bands at 357 nm (2900 M?1 cm?1, 407 nm (3500 M?1 cm?1), 505 nm (300 M?1 cm?1), 570 nm (?130 M?1 cm?1), and 680 nm (?80 M?1 cm?1). The absorption and CD spectra are similar to those of nickel(II) azurin and nickel(II) aspartate transcarbamoylase and prove coordination of the nickel(II) ions to sulfur in a distorted tetrahedral coordination geometry. Changes of the spectra upon ligand binding at the metal or conformation changes of the protein induced by coenzyme, or both, indicate alterations of the metal geometry.The chromophoric substrate trans-4-(N, N-dimethylamino)-cinnamaldehyde forms a ternary complex with Ni(II) liver alcohol dehydrogenase and the coenzyme analogue 1,4,5,6-tetrahydronicotinamide-adenine-dinucleotide, stable between pH 6 and 10. The corresponding ternary complex with NADH is only stable at pH > 9.0. The spectral redshifts induced in the substrate are 11 nm larger than those found in the zinc enzyme. We suggest direct coordination of the substrate to the catalytic metal ion which acts as a Lewis acid in both substrate coordination and catalysis. 相似文献
3.
The relationship between leaf resistance to water vapour diffusion and each of the factors leaf water potential, light intensity and leaf temperature was determined for leaves on seedling apple trees (Malus sylvestris Mill. cv. Granny Smith) in the laboratory. Leaf cuticular resistance was also determined and transpiration was measured on attached leaves for a range of conditions. Leaf resistance was shown to be independent of water potential until potential fell below — 19 bars after which leaf resistance increased rapidly. Exposure of leaves to CO2-free air extended the range for which resistance was independent of water potential to — 30 bars. The light requirement for minimum leaf resistance was 10 to 20 W m?2 and at light intensities exceeding these, leaf resistance was unaffected by light intensity. Optimum leaf temperature for minimum diffusion resistance was 23 ± 2°C. The rate of change measured in leaf resistance in leaves given a sudden change in leaf temperature increased as the magnitude of the temperature change increased. For a sudden change of 1°C in leaf temperature, diffusion resistance changed at a rate of 0.01 s cm?1 min?1 whilst for a 9°C leaf temperature change, diffusion resistance changed at a rate of 0.1 s cm?1 min?1. Cuticular resistance of these leaves was 125 s cm?1 which is very high compared with resistances for open stomata of 1.5 to 4 s cm?1 and 30 to 35 s cm?1 for stomata closed in the dark. Transpiration was measured in attached apple leaves enclosed in a leaf chamber and exposed to a range of conditions of leaf temperature and ambient water vapour density. Peak transpiration of approximately 5 × 10?6 g cm?2 s?1 occurred at a vapour density gradient from the leaf to the air of 12 to 14 g m?3 after which transpiration declined due presumably to increased stomatal resistance. Leaves in CO2-free air attained a peak transpiration of 11 × 10?6 g cm?2 s?1 due to lower values of leaf resistance in CO2 free air. Transpiration then declined in these leaves due to development of an internal leaf resistance (of up to 2 s cm?1). The internal resistance was masked in leaves at normal CO2 concentrations by the increase in stomatal resistance. 相似文献
4.
Gautam G. Yadav Jungsang Cho Damon Turney Brendan Hawkins Xia Wei Jinchao Huang Sanjoy Banerjee Michael Nyce 《Liver Transplantation》2019,9(48)
The recent trend in zinc (Zn) anode aqueous batteries has been to explore layered structures like manganese dioxides and vanadium oxides as Zn‐ion intercalation hosts. These structures, although novel, face limitations like their layered counterparts in lithium (Li)‐ion batteries, where the capacity is limited to the host's intercalation capacity. In this paper, a new strategy is proposed in enabling new generation of energy dense aqueous‐based batteries, where the conversion reactions of rock salt/spinel manganese oxides and carbon nanotube‐nested nanosized Zn electrodes are exploited to extract significantly higher capacity compared to intercalation systems. Accessing the conversion reactions allows to achieve high capacities of 750 mAh g?1 (≈30 mAh cm?2) from manganese oxide (MnO) and 810 mAh g?1 (≈30 mAh cm?2) from nanoscale Zn anodes, respectively. The high areal capacities help to attain unprecedented energy densities of 210 Wh per L‐cell and 320 Wh per kg‐total (398 Wh per kg‐active) from aqueous MnO|CNT‐Zn batteries, which allows an assessment of its viable use in a small‐scale automobile. 相似文献
5.
Except for buckwheat, no cereal or pseudocereal contains any detectable rutin. This study was carried out to compare the rutin content in leaves treated with various concentrations of salicylic acid (SA) (50?mg?l?1, 100?mg?l?1, 150?mg?l?1) for various lengths of time (2?C120?h) to those of untreated F. tartaricum. Rutin content in leaves during the early stages of SA treatment (100?mg?l?1, 150?mg?l?1; 24?C48?h) were higher than at other times. The highest rutin content (40.3?mg?gFW?1) was found in leaves treated with 150?mg?l?1 SA for 48?h. We cloned partial cDNAs of five genes known to be related to rutin biosynthesis from the leaves of F. tataricum using RACE. These genes were chalcone synthase (FtCHS), flavonol synthase (FtFLS-like), flavone 3-hydroxylase (FtF3H), 4-coumaroyl CoA ligase (Ft4CL), and 4-coumaroyl CoA ligase 2 (Ft4CL2). The protein sequences of these genes were analyzed by similarity searching and phylogenetic trees. Apart from the FtFLS-like gene, which had poor identity with F. esculentum, the other genes showed high similarity to those in F. esculentum. During the early stages of SA treatment (24?C48?h), expression levels of four genes (FtCHS, FtFLS-like, FtF3H, and Ft4CL) were higher than controls but that of Ft4CL2 was not. Most notably, the expression level of FtFLS-like 24?h after application of 150?mg?l?1 SA was 14.79 times of the control. These results suggest that rutin content can be enhanced to great extent by SA treatment and the gene expression patterns of rutin-biosynthesis-related genes are regulated by SA. 相似文献
6.
Helena Oliveira António S. Barros Ivonne Delgadillo Manuel A. Coimbra Conceição Santos 《Environmental and Experimental Botany》2009,65(1):1-10
The impacts of salt stress and inoculation in in vitro grapevine (Vitis vinifera L.) growth, nutrient accumulation, osmoregulation, photosynthesis and membrane integrity were evaluated. One month exposure to 100 mM NaCl as well as to inoculation with Phaeomoniella chlamydospora reduced relative growth rate (RGR) and induced senescence in grapevine plants, shown by: (1) decrease of Ψπ without osmoregulation, (2) decrease of chlorophyll content and fluorescence, (3) loss of membrane integrity and (4) nutritional disorders. To assess putative changes in structural and/or non-structural carbohydrates induced by these two stress conditions, alcohol insoluble residues from the roots, stems and leaves were also characterised by FT-IR and GC with respect to the sugar composition. The referred organs were distinguished based on: (1) higher proportion of uronic acid residues in leaves which diagnose the presence of pectic polysaccharides (wavenumbers 1100, 1150 and 1018 cm?1 in FT-IR spectra), (2) higher proportion of xylose and glucose on stems and FT-IR spectra diagnostic of xylose-rich polysaccharides (1041 cm?1) and cellulose (1060 cm?1), (3) higher proportion of glucose residues, xylose and arabinose on roots and a FT-IR spectra characteristic of xylose-rich polysaccharides (1041 cm?1). The main alterations induced by salt stress and inoculation were more visible in leaves, where the content of uronic acid decreased showing that changes in cell wall composition occurred, mostly at the pectic fraction. Besides, an accumulation of insoluble glucose was found, and FT-IR spectra showed that this glucose-based material was starch (maximum absorption at 998 cm?1), accumulated as a non-specific response to salt stress and P. chlamydospora inoculation. 相似文献
7.
Edward A. Drew 《Journal of experimental marine biology and ecology》1978,31(2):173-194
Measurements of photosynthesis, dark respiration, and leaf chlorophyll content were made in the laboratory on both shallow (1 to 5 m) and deep (25 to 33 m) leaves of Cymooceu nodosa (Ucria) Aschers, and Posidonia oceanica (L.) Delile in Malta in April and August. Light saturated photosynthetic rates in Cymodocea were similar in spring (18 μg C cm?2h?1) and summer (25μg Ccm?2h?1) if the 9 C increase in water temperature in summer is taken into account: however, photosynthetic rates in Posidonia were higher in spring than in summer, especially in shallow leaves which fixed ≈ 10 μg C cm?2h?1 in spring but less than half that in summer when rates of carbon accretion were close to compensation point. Levels of irradiance at which photosynthesis was light saturated (Iλ were ≈ 3 mW cm?2 PAR for Cymodocea and 2 mW cm?2 PAR for Posidonia: underwater irradiance at the lower depth limit for these plants (≈33 m) was ≈3 mW cm?2 PAR. corresponding closely to the saturation irradiances. Compensation irradiance for both species was between 0.3 and 0.5 mW cm?2 PAR.Photosynthesis in both species had a temperature optimum at about 30 C (slightly higher in Cymodocea in summer). Dark respiration rates were generally similar in spring and summer, in the region of 3 μg C cm?2 h?1 in Cymodocea and 1.5 to 2 μg C cm?2 h?1 in Posidonia. Increase in dark respiration rates with increased temperature was considerably greater in spring than in summer in both species. Photosynthesis was directly proportional to chlorophyll content in Posidonia in the range encountered (up to 58 μg Chl cm?2) and the summer reduction in photosynthesis was closely correlated with reduction in chlorophyll content. It seems unlikely that environmental factors such as seasonal changes in light intensity, nutrient availability or water temperature were directly responsible for this loss of chlorophyll and it is suggested that this is a manifestation of general leaf senescence, probably induced by daylength changes but possibly enhanced by increased water temperature. Cymodocea showed a similar reduction in chlorophyll content in summer but this was not reflected in reduced photosynthesis. Thus, although Cymodocea may grow rapidly throughout the spring and summer with an overall productivity of 3.6 g C m?2 day?1 in shallow water, the luxuriant growths of Posidonia must develop in the first half of the year when a dense meadow may produce up to 2.1 g C m?2 day?1 in shallow water, declining to ?0.6 g C m?2 day?1 in summer. 相似文献
8.
R. L. C. Giordano R. C. Giordano C. L. Cooney 《Bioprocess and biosystems engineering》2000,23(2):159-166
In this work different aspects of the glucose-fructose enzymatic isomerization, using immobilized glucose isomerase, are studied and quantified. Reaction temperatures range from 40?°C to 60?°C. Intra-particle effective diffusivities (D e), determined after uptake experiments, are between 1.20?×?10?6?cm2/s, at 40?°C, and 2.52?×?10?6?cm2/s, at 60?°C. The estimated energy of activation for diffusion (E aD) is 7.71?kcal/mol. No significant adsorption of the sugars on the support gel matrix is observed. Crushed particles (φ = 150–350?μ) are used during kinetic experiments. For this range of particle diameters, inherent kinetics is approached. A reversible Michaelis–Menten rate equation is fitted to the data, providing the following parameters at pH = 7.0: k 0 = 2.15?×?10?6?g/IU/s; E a/R = 8998?K. Glucose (K G) and fructose (K F) affinity constants are essentially the same, ranging from 0.190?M, at 40?°C to 0.305?M, at 60?°C. The thermodynamic equilibrium constant is determined for the three temperatures, and the heat of reaction, estimated from a Van't Hoff plot, is ΔH = 1682?cal/mol. Independent experiments, where the reaction occurs in the presence of significant intra-particle mass transfer resistance, are used as validation tests. 相似文献
9.
Jerónimo Guzmán-Deara Homero Reyes-De la Cruz Elda María Beltrán-Peña Elda Castro-Mercado Ernesto García-Pineda 《Protoplasma》2013,250(3):779-785
Superoxide dismutase (SOD) activities of the oomycete Phytophthora cinnamomi were examined. Five polypeptides with manganese superoxide dismutase (MnSOD) activity were found in mycelium growing in liquid culture with relative molecular weights ranging from approximately 25 to 100 kDa. Comparison with characterized avocado SODs showed no evidence for the presence of either iron or copper/zinc SODs in P. cinnamomi. The level of activity of the MnSOD polypeptides decreased in the presence of avocado root or cell wall components. Growth of P. cinnamomi, measured as dry weight, increased when the mycelium was grown in the presence of superoxide anion (O2 ?), which was added exogenously. Our results suggest that the metabolism of O2 ? has an important role in the development of P. cinnamomi. 相似文献
10.
Growth,physiological, biochemical and ionic responses of pistachio seedlings to mild and high salinity 总被引:1,自引:0,他引:1
Roghieh Hajiboland Fahimeh Norouzi Charlotte Poschenrieder 《Trees - Structure and Function》2014,28(4):1065-1078
Key message
Depending on salt concentrations, different mechanisms are involved in the tolerance of pistachio and an acclimation to salinity conditions occurs in the leaves that develop in the presence of salt.Abstract
Pistachio (Pistacia vera L.) is a salt tolerant species that is considered an alternative crop for cultivation in salinzied orchard soils. In this work, 12-week-old pistachio seedlings cultivated in soil under greenhouse conditions were treated with five levels of salinity including control (0.63 dSm?1), low (2 and 4 dSm?1) and high (8 and 10 dSm?1) salt concentrations for further 12 weeks. Plant growth parameters were not affected by mild salinity; a significant reduction was only observed from 8 dSm?1. Considerable differences were observed between the young and mature leaves regarding osmotic and ionic stress effects of salt. Main compatible solutes were proline in mature leaves, proline and soluble sugars in young leaves, and soluble sugars and amino acids, other than proline, in roots. Concentration and content of Na in the leaves were not significantly increased at low levels of salinity and the K:Na and Ca:Na ratio of leaves were affected only by higher salt concentrations. Using the sequential extraction procedure for cell wall isolation, we observed that both absolute and relative amounts of Na in the cell wall fraction increased under low salinity, while decreased under higher levels of salt supply. Stable water relations, photochemistry and CO2 assimilation rates particularly of young leaves, as well as ion homeostasis were mechanisms for maintenance of plants growth under mild salinity. Under severe saline conditions, the impaired ability of mature leaves for synthesis of assimilates, preferent allocation of carbohydrates to roots for maintenance of osmotic homeostasis and finally, reduction of protein synthesis caused growth inhibition in pistachio. 相似文献11.
Karin Kikamägi Katri Ots Tatjana Kuznetsova Aleksander Pototski 《Trees - Structure and Function》2014,28(1):53-64
Key message
Use of wood ash or a mixture of wood and oil shale ashes increases the concentrations of P and K in the assimilation organs of conifers and stimulates tree growth.Abstract
The effect of fertilization with wood ash (10 and 15 t ha?1) and a mixture of wood ash (10 t ha?1) and oil shale ash (8 t ha?1) on the growth (height, root collar diameter, biomass, biomass production) and nutrient concentrations in subsoil and needles of young Pinus sylvestris and Picea abies plants on the Puhatu (Northeast Estonia) cutaway peatland in the first 2 years were studied. After the second growing year differences in the average height growth of P. abies and P. sylvestris were statistically significantly higher on ash-treated plots than on the control plots (p < 0.05), being respectively 1.4–1.6 and 1.5–1.7 times greater than height growth of the control trees. The best results on root collar diameter were observed on mixture ash treatments: the root collars were 1.9 (P. abies) and 2.2 (P. sylvestris) times larger than of the control trees. The biomass of the two conifer species and the biomass production of P. sylvestris in 2012 was the greatest on the mixture ash treatments. Five months after fertilization with ashes the concentrations of P, K, Ca and Mg were higher on the treated plots than on the control plot. Although the concentrations of P and K in P. sylvestris needles rose after the treatment with ash, seedlings suffered from P and K deficiency. The concentrations of P and K in P. abies needles were on optimum. The P/N and the K/N ratios in needles were also improved compared to control trees needles. 相似文献12.
Pertti V. Eloranta 《Hydrobiologia》1982,96(3):253-265
Periphyton (Aufwuchs) accumulation was measured on artificial substrates in a pond in central Finland which receives warm
cooling-water effluent from a power plant. The growth of periphyton was generally more rapid on the substrates during the
first two weeks of colonization near the inflow of the warm water effluent than in the middle of the pond. The maximum accumulation
of periphyton was in spring and autumn (dry weight maximum at warm effluent was in spring 3.5 mg DW cm−2,2.65 mg AFDW cm−2; chlorophyll a maximum 3.96 μg cm−2 was found in autumn at pond-middle station). During mid-winter months the growth was strongly limited by solar radiation,
but the growth was also slow at both stations in the summer months, when the power plant was out of operation. The periphyton
accumulation rate was fastest near the water surface and decreased rapidly with increasing depth. A total of 167 diatom species
were found in periphyton samples. However, most species were rare; many of the dominants were common to both plankton and
periphyton. Species similarity analyses (Jaccard's similarity) between 10 different diatom communities (including periphyton
from 9 different types of substrates and phytoplankton) indicated low similarity index values although differences between
communities were not significant. 相似文献
13.
Eutectic‐Derived Mesoporous Ni‐Fe‐O Nanowire Network Catalyzing Oxygen Evolution and Overall Water Splitting
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The development of efficient and abundant water oxidation catalysts is essential for the large‐scale storage of renewable energy in the form of hydrogen fuel via electrolytic water splitting, but still remains challenging. Based upon eutectic reaction and dealloying inheritance effect, herein, novel Ni‐Fe‐O‐based composite with a unique mesoporous nanowire network structure is designed and synthesized. The composite exhibits exceptionally low overpotential (10 mA cm?2 at an overpotential of 244 mV), low Tafel slope (39 mV dec?1), and superior long‐term stability (remains 10 mA cm?2 for over 60 h without degradation) toward oxygen evolution reaction (OER) in 1 m KOH. Moreover, an alkaline water electrolyzer is constructed with the Ni‐Fe‐O composite as catalyst for both anode and cathode. This electrolyzer displays superior electrolysis performance (affording 10 mA cm?2 at 1.64 V) and long‐term durability. The remarkable features of the catalyst lie in its unique mesoporous nanowire network architecture and the synergistic effect of the metal core and the active metal oxide, giving rise to the strikingly enhanced active surface area, accelerated electron/ion transport, and further promoted reaction kinetics of OER. 相似文献
14.
Katrin Jõgar Aare Kuusik Luule Metspalu Külli Hiiesaar Maria Grishakova & Anne Luik 《Entomologia Experimentalis et Applicata》2008,126(2):165-173
Effects of Neem EC (The Indian Neem Tree CompanyTM, 1% azadirachtin) on gas exchange cycles, tracheal ventilation, and water loss in diapausing pupae of the large white butterfly, Pieris brassicae L. (Lepidoptera: Pieridae), were studied using a constant volume respirometer combined with an infrared probe actograph. The non‐treated pupae displayed discontinuous gas exchange cycles (DGC) with a trend coinciding with the bursts of carbon dioxide (CO2) release, active tracheal ventilation, and the heartbeat periods. Two independent forms of tracheal ventilation were observed, relatively vigorous abdominal shaking movements and weak abdominal pulsations. The ability to respond to mechanical excitation with abdominal movements was entirely lost on the 2nd day after treatments with Neem EC, and also a reduced tendency to use a DGC was observed. During 2–3 days after treatments, the DGCs and gas exchange microcycles were entirely lost, as was active ventilation. Before treatments, body mass loss, that is, water loss, was 0.6–0.9 mg g?1 day?1. After the treatments, water loss increased to 3–5 mg g?1 day?1. The pupae remained alive for 10–15 days after the treatments and died after having lost about 50% of their initial body mass. The absence of heartbeats measured during at least 4–5 h was the main criterion for ascertaining death of pupae. The results suggested that respiratory failures, that is, the loss of cyclic gas exchange, evoked by Neem EC were the primary cause of lethal desiccation. Thus, the hypothesis that the cyclic gas exchange is an adaptation for restricting water losses in insects was supported. 相似文献
15.
Calcium-binding stoichiometry, dissociation equilibrium constants at zero ionic strength (K0), and molar extinction difference coefficients (Δ?λ) at the wavelength λ of the metallochromic indicators arsenazo I (ArsI) and tetramethylmurexide (TMX) were reevaluated with a computerized method based on mass conservation and thermodynamic consistency checks. This new method is shown to provide a more critical assessment of the assumed calcium-dye complexing model than is afforded by the commonly used reciprocal-plot method. The analyses of spectrophotometric Ca titrations confirm that both dyes form only 1:1 complexes in aqueous solution. For TMX, K0 = 1.3 × 10?3m and Δ?480 = 1.5 × 104m?1 cm?1; for ArsI, K0 = 5.8 × 10?3m and Δ?562 = 1.8 × 104m?1 cm?1 at pH 7.0 and T = 293°K. The discriminatory power of the analytical method is demonstrated by comparison of these results with those found for a different dye, arsenazo III, which complexes Ca in 1:1, 1:2, and 2:1 forms. 相似文献
16.
Effect of Pulsed Electric Field Treatments on Permeabilization and Extraction of Pigments from Chlorella vulgaris 总被引:1,自引:0,他引:1
Elisa Luengo Santiago Condón-Abanto Ignacio Álvarez Javier Raso 《The Journal of membrane biology》2014,247(12):1269-1277
The effect of pulsed electric field (PEF) treatments of different intensities on the electroporation of the cytoplasmatic membrane of Chlorella vulgaris, and on the extraction of carotenoids and chlorophylls were investigated. Staining the cells with propidium iodide before and after the PEF treatment revealed the existence of reversible and irreversible electroporation. Application of PEF treatments in the range of 20–25 kV cm?1 caused most of the population of C. vulgaris to be irreversibly electroporated even at short treatment times (5 pulses of 3 µs). However, at lower electric field strengths (10 kV cm?1), cells that were reversibly electroporated were observed even after 50 pulses of 3 µs. The electroporation of C. vulgaris cells by PEF higher than 15 kV cm?1 and duration is higher than 15 µs increased significantly the extraction yield of intracellular components of C. vulgaris. The application of a 20 kV cm?1 for 75 μs increased the extraction yield just after the PEF treatment of the carotenoids, and chlorophylls a and b 0.5, 0.7, and 0.8 times, respectively. However, further increments in electric field strength and treatment time did not cause significant increments in the extraction yield. The extraction of carotenoids from PEF-treated C. vulgaris cells after 1 h of the application of the treatment significantly increased the extraction yield in comparison to the yield obtained from the cells extracted just after the PEF treatment. After PEF treatment at 20 kV cm?1 for 75 µs, extraction yield for carotenoids, and chlorophylls a and b increased 1.2, 1.6, and 2.1 times, respectively. A high correlation was observed between irreversible electroporation and percentage of yield increase when the extraction was conducted after 1 h of the application of PEF treatment (R: 0.93), but not when the extraction was conducted just after PEF treatment (R: 0.67). 相似文献
17.
G. Courtois de Vi?ose A. Porta M. P. Viera H. Fernández-Palacios M. S. Izquierdo 《Journal of applied phycology》2012,24(6):1427-1437
Diatom cell quantity and their biochemical composition vary among species and are greatly affected by harvest stage or culture conditions. This study compares growth pattern, cell attachment, and biochemical composition of four diatoms suitable for abalone post-larvae: Navicula incerta, Proschkinia sp., Nitzschia sp., and Amphora sp. The four diatoms were grown in F/2 medium at 28.5?±?1.4°C, under 62?±?8?μmol?photons?m?2?s?1, at different original inoculating densities (0.05?×?106, 0.10?×?106, and 0.25?×?106?cells?mL?1) and were harvested in log and stationary phase of growth for biochemical analysis. Total protein, carbohydrate, lipid, and ash composition, as well as fatty acid composition, were determined. All diatoms grew better when inoculated at 0.10?×?106?cell?mL?1 with Proschkinia sp. reaching the highest cell density of 6.56?×?106?cells?mL?1 in log phase. Amphora sp. had the highest cell attachment capacity when inoculated at 0.10?×?106?cell?mL?1 (11,580?cells?mm?2), whereas N. incerta had the lowest (7,750?cells?mm?2). Protein and lipid (percent dry weight) contents were generally highest in cells during log phase of growth; Amphora sp. in log phase of growth had the highest lipid content of 9.74% DW, whereas significant differences in carbohydrate between the two growth phases were only observed for Proschkinia sp. Besides, all diatoms had higher energy contents in log phase of growth. There were no significant differences in ash content among the four diatoms. Polyunsaturated fatty acid (PUFA) content ranged from 23.25% to 38.62% of the total fatty acids, and the four diatoms tested were richer in n-3 PUFA than in n-6 PUFA. All the diatoms had significant quantities of 20:5n-3 (EPA) (between 12.69% and 17.68% of TFA), and Proschkinia sp., in log phase of growth, had the highest quantity of arachidonic acid (20:4n-6; ARA). The results highlight the influence of culture conditions and harvest protocols on diatom nutritive value and enabled a preliminary approach towards the selection of novel diatom species. 相似文献
18.
Mostafa Khajeh 《Biological trace element research》2010,138(1-3):337-345
In this study, silver nanoparticles were prepared and used for separation and preconcentration of manganese from biological samples. The technical feasibility of silver nanoparticles for manganese removal was investigated under batch studies. The effects of different parameters such as pH of solution, time (t), amounts of PAN (E), and silver nanoparticles (N) on the adsorption of manganese by silver nanoparticle were investigated using factorial design and response surface methodology based on Box–Behnken design. Thermodynamic parameters indicate the adsorption process to be exothermic. The limit of detection of the proposed method followed by inductively coupled plasma was found to be 0.08?µg L?1. The method was applied to determine of manganese in biological samples. 相似文献
19.
Bernal M García-Alcalde F Concha A Cano C Blanco A Garrido F Ruiz-Cabello F 《Cancer immunology, immunotherapy : CII》2012,61(6):803-816