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1.
Foods ; 13(9)2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38731659

ABSTRACT

The research is focused on the quantitative evaluation of the flaxseed (Linum usitatissimum L.) proteome at the level of seed cake (SC), fine flour-sieved a fraction below 250 µm (FF)-and protein concentrate (PC). The evaluation was performed on three oilseed flax cultivars (Agriol, Raciol, and Libra) with different levels of α-linolenic acid content using LC-MS/MS (shotgun proteomics) analysis, which was finalized by database searching using the NCBI protein database for Linum usitatissimum and related species. A total of 2560 protein groups (PGs) were identified, and their relative abundance was calculated. A set of 33 quantitatively most significant PGs was selected for further characterization. The selected PGs were divided into four classes-seed storage proteins (11S globulins and conlinins), oleosins, defense- and stress-related proteins, and other major proteins (mainly including enzymes). Seed storage proteins were found to be the most abundant proteins. Specifically, 11S globulins accounted for 41-44% of SC proteins, 40-46% of FF proteins, and 72-84% of PC proteins, depending on the cultivar. Conlinins (2S albumins) were the most abundant in FF, ranging from 10 to 13% (depending on cultivar). The second most important class from the point of relative abundance was oleosins, which were represented in SC and FF in the range of 2.1-3.8%, but only 0.36-1.20% in PC. Surprisingly, a relatively high abundance of chitinase was found in flax products as a protein related to defence and stress reactions.

2.
Plant Foods Hum Nutr ; 79(1): 159-165, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38236453

ABSTRACT

Linseed represents a rich source of nutritional, functional and health-beneficial compounds. Nevertheless, the chemical composition and content of bioactive compounds may be quite variable and potentially affected by various factors, including genotype and the environment. In this study, the proximate chemical composition, lignans content and antioxidant potential of six experimentally grown linseed cultivars were assessed and compared. A diagonal cultivation trial in the University of South Bohemia Experimental Station in Ceské Budejovice, Czech Republic, was established in three subsequent growing seasons (2018, 2019 and 2020). The results showed that the cultivar and growing conditions influenced most studied parameters. The lack of precipitation in May and June 2019 negatively affected the seed yield and the level of secoisolariciresinol diglucoside but did not decrease the crude protein content, which was negatively related to the oil content. The newly developed method for lignans analysis allowed the identification and quantification of secoisolariciresinol diglucoside and matairesinol. Their content correlated positively with the total polyphenol content and antioxidant assays (DPPH and ABTS radical scavenging activity), indicating the significant contribution to the biofunctional properties of linseed. On the other hand, we did not detect minor linseed lignans, pinoresinol and lariciresinol. The results of this study showed the importance of cultivar and growing conditions factors on the linseed chemical composition and the lignans content, determining its nutritional and medicinal properties.


Subject(s)
Flax , Glucosides , Lignans , Antioxidants/analysis , Butylene Glycols/analysis , Butylene Glycols/chemistry , Butylene Glycols/metabolism , Flax/chemistry , Lignans/analysis , Lignans/chemistry , Lignans/metabolism
3.
Plants (Basel) ; 13(1)2023 Dec 30.
Article in English | MEDLINE | ID: mdl-38202419

ABSTRACT

As a source of nutritionally important components, hemp seeds are often dehulled for consumption and food applications by removing the hard hulls, which increases their nutritional value. The hulls thus become waste, although they may contain valuable protein items, about which there is a lack of information. The present work is therefore aimed at evaluating the proteome of hemp (Cannabis sativa L.) at the whole-seed, dehulled seed, and hull levels. The evaluation was performed on two cultivars, Santhica 27 and Uso-31, using LC-MS/MS analysis. In total, 2833 protein groups (PGs) were identified, and their relative abundances were determined. A set of 88 PGs whose abundance exceeded 1000 ppm (MP88 set) was considered for further evaluation. The PGs of the MP88 set were divided into ten protein classes. Seed storage proteins were found to be the most abundant protein class: the averages of the cultivars were 65.5%, 71.3%, and 57.5% for whole seeds, dehulled seeds, and hulls, respectively. In particular, 11S globulins representing edestin (three PGs) were found, followed by 7S vicilin-like proteins (four PGs) and 2S albumins (two PGs). The storage 11S globulins in Santhica 27 and Uso-31 were found to have a higher relative abundance in the dehulled seed proteome (summing to 58.6 and 63.2%) than in the hull proteome (50.5 and 54%), respectively. The second most abundant class of proteins was oleosins, which are part of oil-body membranes. PGs belonging to metabolic proteins (e.g., energy metabolism, nucleic acid metabolism, and protein synthesis) and proteins related to the defence and stress responses were more abundant in the hulls than in the dehulled seeds. The hulls can, therefore, be an essential source of proteins, especially for medical and biotechnological applications. Proteomic analysis has proven to be a valuable tool for studying differences in the relative abundance of proteins between dehulled hemp seeds and their hulls among different cultivars.

4.
Antioxidants (Basel) ; 11(10)2022 Oct 13.
Article in English | MEDLINE | ID: mdl-36290745

ABSTRACT

The utilization of plant by-products as functional food ingredients has received increasing attention in the last decade. One such by-product generated during milk thistle oil pressing is oilseed cakes, which could be used as a novel food ingredient. Therefore, the study aimed at investigating the effects of the addition of milk thistle oilseed cake (MTOC) flour fractions obtained via dry sieving, differing in particle size (unsieved; coarse: >710 µm; medium: 315−710 µm; and fine: <315 µm), on the quality of gluten-free bread and stability of silymarin during breadmaking. The 10% addition of the fractions into gluten-free bread increased the protein, fibre, fat, ash and silymarin content. The breads with the coarse fraction had the highest content of fibre, whereas the breads with the fine fraction excelled in protein, fat and ash content. The medium fraction was characterized as the richest source of silymarin, whilst the fine fraction was the poorest. Silymarin constituents were slightly released during dough rising but also partially decomposed during baking; moreover, silydianin was the most susceptible and degraded the most. The enriched breads had better sensory and textural properties compared to the control bread. The results suggest that MTOC flour fractions can improve the potential health benefits and nutritional profile of gluten-free bread.

5.
J Agric Food Chem ; 70(37): 11689-11703, 2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36094395

ABSTRACT

The influence of pumpkin seed roasting conditions (110-140 °C) and screw-pressing on the formation of previously undescribed Δ7-phytosterol oxidation products and tocopherylquinone adducts with nucleophilic phosphatidylethanolamine species was investigated. The roasting process of pumpkin seed paste at a temperature above 120 °C for 30 min considerably enhanced the formation of Δ7-oxysterols. Targeted analysis [electron impact mass spectrometry (MS), 1D-nuclear magnetic resonance] led to the identification of five novel markers of pumpkin paste roasting, among which (3ß,5α,22E,24S)-stigmasta-7,22-dien-6-one-3-ol (6-oxo-α-spinasterol), stereoisomers of (3ß,5α,22E)-7,8-epoxystigmast-22-en-3-ol (7,8-epoxy-α-spinasterol), and (3ß,5α)-22,23-epoxystigmast-7-en-3-ol (7,8-epoxy-α-spinasterol) were reported in edible oils for the first time. Simulated culinary processing provided novel stereoisomers of (3ß,5α,22E)-stigmasta-7,22-dien-3,6-diol, unusual (3ß,5α,22E)-stigmasta-7,22-dien-6,15-dione-3-ol, and (5α,22E)-stigmasta-7,22-dien-3-one accompanied by minor stereoisomers of (3ß,5α)-7,8;22,23-diepoxystigmastan-3-ol. Moreover, a clear relationship between the pumpkin seed oil stability index and synergistic effect of glycerophospholipids with present tocochromanols was found. High-resolution atmospheric pressure chemical ionization-MS experiments clearly demonstrated the formation of various γ-tocopherylquinone adducts with primary amines, namely, octylamine. The mitigation strategy of potentially detrimental oxysterols from pumpkin seed oil included optimization of processing parameters while maintaining the formation of desirable sensory-active compounds.


Subject(s)
Cucurbita , Oxysterols , Phytosterols , Amines , Bone Screws , Phosphatidylethanolamines , Plant Oils/chemistry , Temperature , Vitamin E/analogs & derivatives
6.
Foods ; 11(15)2022 Aug 02.
Article in English | MEDLINE | ID: mdl-35954070

ABSTRACT

Flaxseed is an excellent source of valuable nutrients and is also considered a functional food. There are two types of hydrocolloids in flaxseed: flaxseed gum and proteins. Flaxseed gum exhibits emulsifying and foaming activities or can be used as a thickening and gelling agent. Due to its form of soluble fiber, flaxseed gum is related to many health benefits. Flaxseed proteins have various functional properties based on their physicochemical properties. While albumins possess the emulsion-forming ability, globulins better serve as foaming agents. Flaxseed proteins may also serve as a source of functional peptides with interesting biological and health-related activities. Functional properties and health-related benefits predetermine the application of these hydrocolloids, mainly in the food industry or medicine. Although these properties of flaxseed hydrocolloids have been recently and extensively studied, they are still not widely used on the industrial scale compared to other popular plant gums and proteins. The aim of this review was to present, discuss and highlight the recent discoveries in the structural characteristics and functional and biological properties of these versatile hydrocolloids with respect to factors affecting their characteristics and offer new insights into their potential applications as comparable alternatives to the other natural hydrocolloids or as the sources of novel functional products.

7.
Nanomaterials (Basel) ; 12(14)2022 Jul 18.
Article in English | MEDLINE | ID: mdl-35889684

ABSTRACT

The effect of magnetic nanoparticles size and concentration on nematic liquid crystal (NLC) behavior in a magnetic field was investigated. The magneto-optical investigation using measurements of the light transmission through the liquid crystal was used to study the structural changes induced by an applied weak magnetic field. Magnetic nanoparticles Fe3O4 of spherical shape with different size and volume concentration were added to NLC 4-cyano-40 -hexylbiphenyl (6CB) during its isotropic phase. In contrast to undoped liquid crystals, the distinctive different light transmission responses induced by a magnetic field in studied NLC samples were observed suggesting both structural changes and the orientational coupling between magnetic moments of nanoparticles and the director of the NLC. Experimental measurements were conducted, including investigation under linearly increasing and/or jumped magnetic field, respectively, as well as the investigation of time influence on structural changes to study their stability and switching time. The analysis of observed light transmission characteristics confirmed the role of concentration and size of magnetic nanoparticles on the resultant behavior of investigated NLC compounds. The obtained results showed the lowering of the threshold magnetic field with an increase in the volume concentration of nanoparticles and on the important role of nanoparticles size on stability and switching properties. Obtained results are discussed within the context of previous ones.

8.
Foods ; 10(11)2021 Nov 05.
Article in English | MEDLINE | ID: mdl-34828984

ABSTRACT

Black garlic (BG) is a product originating from fresh garlic (FG) and substantially differs in many aspects from FG due to the process called ageing. During this thermal process, the health-promoting properties of FG are enhanced, and the sensory traits are altered. However, very little is known about how the physicochemical properties of different FG varieties affect these properties of BG. Thus, the aim of this study was to investigate the influence of seven FG varieties subjected to the thermal process on the physicochemical parameters of BG. To prepare the BG samples, a fifteen-day ageing process involving a temperature gradient ranging from 30 to 82 °C was used. It was found that the antioxidant activity, the total polyphenol content, and the total soluble solids increased during ageing, while the pH level, moisture content, and lightness decreased in all the garlic varieties. The varieties of garlic differed in the studied traits significantly, both before (FG) and after ageing (BG). In the sensory analysis, significant differences between the BG varieties were observed only in the pleasantness of texture, while the remaining sensory descriptors (pleasantness of color, odor, taste and intensity of the garlic aroma, and overall acceptability) were not affected by variety. The correlations suggest that most of the FG's studied parameters in this study do not correlate with the properties of BG and cannot be used for the prediction of the quality of BG. Additionally, HPLC-MS/MS analysis revealed substantial changes in the composition of low molecular compounds.

9.
Foods ; 10(11)2021 Nov 11.
Article in English | MEDLINE | ID: mdl-34829047

ABSTRACT

Oilseed cakes are produced as a by-product of oil pressing and are mostly used as feed. Their use for human consumption is due to the functional properties and benefits for human health. Herein, oilseed cake flours of eight species (flax, hemp, milk thistle, poppy, pumpkin, rapeseed, safflower, sunflower) were sieved into fractions above (A250) and below (B250) 250 µm. The chemical composition, SDS-PAGE profiles, colour, functional properties and antioxidant activities of these flours were evaluated. The B250 fractions were evaluated as being protein and ash rich, reaching crude protein and ash content ranging from 31.78% (milk thistle) to 57.47% (pumpkin) and from 5.0% (flax) to 11.19% (poppy), respectively. A high content of carbohydrates was found in the flours of hemp, milk thistle and safflower with a significant increase for the A250 fraction, with a subsequent relation to a high water holding capacity (WHC) for the A250 fraction (flax, poppy, pumpkin and sunflower). The A250 milk thistle flour was found to have the richest in polyphenols content (TPC) (40.89 mg GAE/g), with the highest antioxidant activity using an ABTS•+ assay (101.95 mg AAE/g). The A250 fraction for all the species exhibited lower lightness than the B250 fraction. The obtained results indicate that sieving oilseed flour with the aim to prepare flours with specific functional characteristics and composition is efficient only in combination with a particular species.

10.
Appl Microbiol Biotechnol ; 103(14): 5533-5547, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31144014

ABSTRACT

Potato proteins are well known for their nutritional, emulsifying, foaming, gel forming or antioxidant properties that all make from them valuable protein source for food industry. Antifungal, antimicrobial and also antiviral properties, described for potato proteins in the review, enrich the possibilities of potato protein usage. Potato proteins were divided into patatin, protease inhibitors and fraction of other proteins that also included, besides others, proteins involved in potato defence physiology. All these proteins groups provide proteins and peptides with antifungal and/or antimicrobial actions. Patatins, obtained from cultivars with resistance to Phytophthora infestans, were able to inhibit spore germination of this pathogen. Protease inhibitors represent the structurally heterogeneous group with broad range of antifungal and antimicrobial activities. Potato protease inhibitors I and II reduced the growth of Phytophthora infestans, Rhizoctonia solani and Botrytis cinerea or of the fungi of Fusarium genus. Members of Kunitz family (proteins Potide-G, AFP-J, Potamin-1 or PG-2) were able to inhibit serious pathogens such as Staphylococcus aureus, Listeria monocytogenes, Escherichia coli or Candida albicans. Potato snakins, defensins and pseudothionins are discussed for their ability to inhibit serious potato fungi as well as bacterial pathogens. Potato proteins with the ability to inhibit growth of pathogens were used for developing of pathogen-resistant transgenic plants for crop improvement. Incorporation of potato antifungal and antimicrobial proteins in feed and food products or food packages for elimination of hygienically risk pathogens brings new possibility of potato protein usage.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Fungi/drug effects , Fungicides, Industrial/pharmacology , Plant Proteins/pharmacology , Solanum tuberosum/chemistry , Anti-Bacterial Agents/chemistry , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Candida albicans/drug effects , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/pharmacology , Fungicides, Industrial/chemistry , Listeria monocytogenes/drug effects , Peptides/chemistry , Peptides/pharmacology , Phytophthora/drug effects , Plant Proteins/chemistry , Staphylococcus aureus/drug effects
11.
Dalton Trans ; 46(10): 3252-3264, 2017 Mar 07.
Article in English | MEDLINE | ID: mdl-28224153

ABSTRACT

In this paper, Keggin-type heteropoly acids H3PMo12O40 (PMo12), H3PW12O40 (PW12) and H4SiW12O40 (SiW12) were successfully supported on silica-coated perovskite type LaMnO3 nanoparticles by a simple acid-base reaction. These novel hybrid nanomaterials (denoted as LaMnO3@SiO2/PMo12 (1), LaMnO3@SiO2/PW12 (2), and LaMnO3@SiO2/SiW12 (3)) were characterized by means of FT-IR, PXRD, inductively coupled plasma (ICP) spectrometry, SEM, EDX, TEM and BET surface area analysis. Furthermore, the adsorption abilities of 1-3 were tested towards cationic methylene blue (MB) and anionic methyl orange (MO) dyes. The results revealed that the MB dye can be removed almost completely (≥98%) by adsorbents 1-3 in 1, 30 and 0.5 minutes, respectively. For the most efficient adsorbent 3, the effects of the initial concentration and the initial pH values of MB solution on its adsorption ability were examined. Furthermore, the selective adsorption of the hybrid materials towards mixed MB & MO solution was investigated. The nanomaterials 1-3 could be easily separated from the aqueous solution and reused several times without any impact on their adsorption abilities and structures.

12.
J Nanosci Nanotechnol ; 15(2): 1060-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-26353613

ABSTRACT

There are relatively few nanotechnologies that can produce nanocomposite scaffolds for cell growth. Electrospinning has emerged as the foremost method of producing nanofibrous biomimetic scaffolds for tissue engineering applications. In this study diamond nanoparticles were integrated into a polymer solution to develop a nanocomposite scaffold containing poly(lactide-co-glycolide) (PLGA) loaded with diamond nanoparticles. To investigate the effect of adding diamond nanoparticles to PLGA scaffolds, primary human mesenchymal stem cells (hMSCs) were seeded on the scaffolds. The cytocompatibility results showed that addition of diamond nanoparticles did not impinge upon cell proliferation, nor was there a cytotoxic cellular response after 9 days in culture. Scanning electron microscopy, transmission electron microscopy, atomic force microscopy and confocal microscopy enabled qualitative characterization of the fibres and revealed cell morphology and number. Furthermore, surface roughness was measured to evaluate diamond nanoparticle modifications, and no significant difference was found between the diamond nanocomposite and pure polymer scaffolds. On the other hand, bright spots on phase images performed by atomic force microscopy suggested a higher hardness at certain points on fibers of the PLGA-nanodiamond composites, which was supported by nanoindentation measurements. This study shows that PLGA nanofibers can be reinforced with nanodiamond without adversely affecting cell behaviour, and thus it sets the foundation for future application of these scaffolds in bone tissue engineering.


Subject(s)
Lactic Acid/chemistry , Mesenchymal Stem Cells/cytology , Nanocomposites/chemistry , Nanodiamonds/chemistry , Osteogenesis/physiology , Polyglycolic Acid/chemistry , Tissue Scaffolds , Bone Substitutes/chemical synthesis , Cells, Cultured , Equipment Design , Equipment Failure Analysis , Humans , Materials Testing , Mesenchymal Stem Cells/physiology , Nanocomposites/ultrastructure , Nanodiamonds/ultrastructure , Particle Size , Polylactic Acid-Polyglycolic Acid Copolymer , Surface Properties
13.
PLoS One ; 9(3): e91685, 2014.
Article in English | MEDLINE | ID: mdl-24626462

ABSTRACT

Various nitric oxide modulators (NO donors--SNP, GSNO, DEA NONOate and scavengers--PTIO, cPTIO) were tested to highlight the role of NO under Cd excess in various ontogenetic stages of chamomile (Matricaria chamomilla). Surprisingly, compared to Cd alone, SNP and PTIO elevated Cd uptake (confirmed also by PhenGreen staining) but depleted glutathione (partially ascorbic acid) and phytochelatins PC2 and PC3 in both older plants (cultured hydroponically) and seedlings (cultured in deionised water). Despite these anomalous impacts, fluorescence staining of NO and ROS confirmed predictable assumptions and revealed reciprocal changes (decrease in NO but increase in ROS after PTIO addition and the opposite after SNP application). Subsequent tests using alternative modulators and seedlings confirmed changes to NO and ROS after application of GSNO and DEA NONOate as mentioned above for SNP while cPTIO altered only NO level (depletion). On the contrary to SNP and PTIO, GSNO, DEA NONOate and cPTIO did not elevate Cd content and phytochelatins (PC2, PC3) were rather elevated. These data provide evidence that various NO modulators are useful in terms of NO and ROS manipulation but interactions with intact plants affect metal uptake and must therefore be used with caution. In this view, cPTIO and DEA NONOate revealed the less pronounced side impacts and are recommended as suitable NO scavenger/donor in plant physiological studies under Cd excess.


Subject(s)
Cadmium/chemistry , Chamomile/drug effects , Nitric Oxide/chemistry , Antioxidants/chemistry , Ascorbic Acid/chemistry , Cyclic N-Oxides/chemistry , Glutathione/chemistry , Imidazoles/chemistry , Microscopy, Confocal , Microscopy, Fluorescence , Nitric Oxide Donors/chemistry , Nitroprusside/chemistry , Reactive Oxygen Species/chemistry , S-Nitrosoglutathione/chemistry , Seeds/drug effects
14.
J Plant Physiol ; 171(3-4): 260-8, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-24054753

ABSTRACT

Barley (Hordeum vulgare cv. Bojos) plants cultured in low nitrogen (N) containing Hoagland solution (20 mg/l) were exposed to N deficiency (-N) over 15 days. Plants revealed relatively high tolerance to total N deficit because shoot length was not altered and dry biomass was depleted by ca. 30% while root length increased by ca. 50% and dry biomass remained unaffected. Soluble proteins and free amino acids decreased more pronouncedly in the roots. Antioxidants (glutathione and ascorbic acid) decreased in the shoots but increased or were not affected in the roots. Ascorbate peroxidase and glutathione reductase activities were depleted in shoots and/or roots while guaiacol peroxidase activity was stimulated in the shoots. In accordance, fluorescence signal of reactive oxygen species (ROS) and nitric oxide was elevated in shoots but no extensive changes were observed in roots if +N and -N treatments are compared. At the level of phenolic metabolites, slight increase in soluble phenols and some phenolic acids and strong elevation of flavonoid homoorientin was found in the shoots but not in the roots. Fluorescence microscopy in terms of detection of phenols is also discussed. We also briefly discussed accuracy of quantification of some parameters owing to discrepancies in the literature. It is concluded that N deficiency induces increase in shoot phenolics but also elevates symptoms of oxidative stress while increase in root antioxidants probably contributes to ROS homeostasis aimed to maintain root development.


Subject(s)
Antioxidants/metabolism , Hordeum/metabolism , Nitrogen/metabolism , Hordeum/chemistry , Oxidative Stress , Reactive Oxygen Species/metabolism
15.
J Biomed Mater Res A ; 102(11): 3918-30, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24375970

ABSTRACT

Various types of nanofibers are increasingly used in tissue engineering, mainly for their ability to mimic the architecture of tissue at the nanoscale. We evaluated the adhesion, growth, viability, and differentiation of human osteoblast-like MG 63 cells on polylactide (PLA) nanofibers prepared by needle-less electrospinning and loaded with 5 or 15 wt % of hydroxyapatite (HA) nanoparticles. On day 7 after seeding, the cell number was the highest on samples with 15 wt % of HA. This result was confirmed by the XTT test, especially after dynamic cultivation, when the number of metabolically active cells on these samples was even higher than on control polystyrene. Staining with a live/dead kit showed that the viability of cells on all nanofibrous scaffolds was very high and comparable to that on control polystyrene dishes. An enzyme-linked immunosorbent assay revealed that the concentration of osteocalcin was also higher in cells on samples with 15 wt % of HA. There was no immune activation of cells (measured by production of TNF-alpha), associated with the incorporation of HA. Moreover, the addition of HA suppressed the creep behavior of the scaffolds in their dry state. Thus, nanofibrous PLA scaffolds have potential for bone tissue engineering, particularly those with 15 wt % of HA.


Subject(s)
Cell Differentiation , Durapatite/chemistry , Nanofibers/chemistry , Osteoblasts/metabolism , Polyesters/chemistry , Bone Substitutes , Cell Adhesion , Cell Line , Cell Survival , Humans , Osteoblasts/cytology , Osteocalcin/biosynthesis , Tissue Engineering/methods
16.
Int J Nanomedicine ; 7: 1931-51, 2012.
Article in English | MEDLINE | ID: mdl-22619532

ABSTRACT

BACKGROUND: Nanofibrous scaffolds loaded with bioactive nanoparticles are promising materials for bone tissue engineering. METHODS: In this study, composite nanofibrous membranes containing a copolymer of L-lactide and glycolide (PLGA) and diamond nanoparticles were fabricated by an electrospinning technique. PLGA was dissolved in a mixture of methylene chloride and dimethyl formamide (2:3) at a concentration of 2.3 wt%, and nanodiamond (ND) powder was added at a concentration of 0.7 wt% (about 23 wt% in dry PLGA). RESULTS: In the composite scaffolds, the ND particles were either arranged like beads in the central part of the fibers or formed clusters protruding from the fibers. In the PLGA-ND membranes, the fibers were thicker (diameter 270 ± 9 nm) than in pure PLGA meshes (diameter 218 ± 4 nm), but the areas of pores among these fibers were smaller than in pure PLGA samples (0.46 ± 0.02 µm(2) versus 1.28 ± 0.09 µm(2) in pure PLGA samples). The PLGA-ND membranes showed higher mechanical resistance, as demonstrated by rupture tests of load and deflection of rupture probe at failure. Both types of membranes enabled the attachment, spreading, and subsequent proliferation of human osteoblast-like MG-63 cells to a similar extent, although these values were usually lower than on polystyrene dishes. Nevertheless, the cells on both types of membranes were polygonal or spindle-like in shape, and were distributed homogeneously on the samples. From days 1-7 after seeding, their number rose continuously, and at the end of the experiment, these cells were able to create a confluent layer. At the same time, the cell viability, evaluated by a LIVE/DEAD viability/cytotoxicity kit, ranged from 92% to 97% on both types of membranes. In addition, on PLGA-ND membranes, the cells formed well developed talin-containing focal adhesion plaques. As estimated by the determination of tumor necrosis factor-alpha levels in the culture medium and concentration of intercellular adhesion molecule-1, MG-63 cells, and RAW 264.7 macrophages on these membranes did not show considerable inflammatory activity. CONCLUSION: This study shows that nanofibrous PLGA membranes loaded with diamond nanoparticles have interesting potential for use in bone tissue engineering.


Subject(s)
Bone Substitutes/chemistry , Diamond/chemistry , Lactic Acid/chemistry , Nanofibers/chemistry , Nanoparticles/chemistry , Polyglycolic Acid/chemistry , Tissue Scaffolds/chemistry , Actin Cytoskeleton/metabolism , Animals , Cell Adhesion , Cell Line , Cell Proliferation , Cell Survival , Humans , Materials Testing , Mice , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Nanofibers/ultrastructure , Nanomedicine , Nanoparticles/ultrastructure , Osteoblasts/cytology , Osteoblasts/immunology , Osteoblasts/physiology , Polylactic Acid-Polyglycolic Acid Copolymer , Tissue Engineering/methods
17.
Inorg Chem ; 50(8): 3743-51, 2011 Apr 18.
Article in English | MEDLINE | ID: mdl-21438499

ABSTRACT

The diffraction data of η'-Cu(3+x)(Si,Ge) were collected by 3D quantitative electron diffraction tomography on a submicrometer-sized sample, and the structure was solved by the charge-flipping algorithm in superspace. It is shown that the structure is trigonal, and it is incommensurately modulated with two modulation vectors q(1) = (α, α, 1/3) and q(2) = (-2α, α, 1/3), superspace group P31m(α, α, 1/3)000(-2α, α, 1/3)000. The modulation functions of some atoms are very complicated and reach amplitudes comparable with the unit cell dimensions. The modulated structure can be described as sheets of Cu clusters separated by honeycomb layers of mixed Si/Ge positions. The shape of the Cu clusters in the sheets strongly varies with the modulation phase, and the predominant form is an icosahedron. The striving of the Cu layers to form icosahedral clusters is deemed to be the main driving force of the modulation. The combination of methods used in this work can be applied to other structures that are difficult to crystallize in large crystals and opens new perspectives, especially for investigations of aperiodic or otherwise complex metallic alloys.

18.
Acta Crystallogr C ; 66(Pt 4): o222-4, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20354316

ABSTRACT

In the title compound, C(20)H(40)N(8).H(2)O, the organic molecule crystallizes with one water molecule located within the molecular cavity of the octaaza macrocycle. The two molecules are linked via two weak O-H...N hydrogen bonds. The assembly has noncrystallographic C(2) axial symmetry.

19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1391, 2010 May 19.
Article in English | MEDLINE | ID: mdl-21579471

ABSTRACT

The crystal structure of the title compound, C(7)H(10)N(+)·H(2)PO(3) (-), has been reported previously by Sabounchei & Naghipour [Asian J. Chem. (2003) ▶, 15, 1677-1686]. A new look at this compound has revealed doubling of the unit cell. The asymmetric unit consists of two 4-methyl-anilinium cations and two dihydrogen phosphite anions. The crystal structure is built upon alternating layers of organic cations and dihydrogen phosphite anions stacked along c. The organic layer is stabilized by C-H⋯π interactions. Weak aromatic π-π stacking interactions with centroid-centroid distances of 4.6147 (12), 4.6917 (12), 4.6932 (13) and 4.8366 (13) Šare also observed in the structure. The dihydrogen phosphite anions are linked by O-H⋯O hydrogen bonds into chains running parallel to the a-axis direction. These chains are connected to the cation layer by N-H⋯O hydrogen bonds.

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