•There is limited data on the mechanisms of fucoidan transformation in the human body after oral administration.•Fucoidans have a great therapeutic potential, but with only preliminary ...pharmacokinetic studies.•Absorption study of fucoidan from Cladosiphon okamuranus demonstrated in Japanese volunteers.•Horizontal transfer of carbohydrate active enzymes from marine bacteria to Japanese guts microbiota.
Fucoidans are a group of homo-and hetero-polysaccharides, which necessarily contains residues of sulfated α-L-fucose. Fucoidans are found only in brown algae. These polysaccharides exhibit a wide spectrum of biological activity and have a great therapeutic potential. Enzymes capable of catalyzing the degradation of fucoidans are absent in the mammalian enzyme system. The question arises: is the transformation of fucoidan in mammals, particularly in human possible? Studies in vivo (in situ) and in vitro have demonstrated that high molecular weight fucoidans are absorbed across rat intestinal epithelial cells, accumulated by liver macrophages, and characterized by low levels in blood and urine. Using the example of the Okinawa Prefecture (Japan) residents, it was shown that Cladosiphon okamuranus alga is digested and the fucoidan contained in this alga is absorbed in the human body.
This review analyzes the issues associated with biodegradation of glyphosate (N-(phosphonomethyl)glycine), one of the most widespread herbicides. Glyphosate can accumulate in natural environments and ...can be toxic not only for plants but also for animals and bacteria. Microbial transformation and mineralization of glyphosate, as the only means of its rapid degradation, are discussed in detail. The different pathways of glyphosate catabolism employed by the known destructing bacteria representing different taxonomic groups are described. The potential existence of alternative glyphosate degradation pathways, apart from those mediated by C-P lyase and glyphosate oxidoreductase, is considered. Since the problem of purifying glyphosate-contaminated soils and water bodies is a topical issue, the possibilities of applying glyphosate-degrading bacteria for their bioremediation are discussed.
The ability of fucoidans to scavenge reactive oxygen species still remains a subject of debate in scientific literature, as shown by an analysis of the results of recent studies on the antioxidant ...activity (AOA) of fucoidans. On the one hand, in vitro and in vivo experiments provide evidence that fucoidans of brown algae can modulate diseases associated with oxidative stress by regulating the antioxidant defense systems and signaling pathways. On the other hand, the use of cell-free assay systems has revealed a relationship between the antioxidant activity attributed to fucoidans and the polyphenolic compounds extracted along with them. The polyphenolic compounds of brown algae referred to as phlorotannins are also known as potent antioxidants. Since the vast majority of studies use various commercial preparations or extracts containing fucoidan and polyphenolic compounds without measuring the level of the latter in polysaccharide samples, there is still no clear understanding of whether fucoidans or co-extracted polyphenolic compounds are a priority component providing AOA.
The degradation of stable organophosphorus pollutants has been studied in six soil bacterial isolates and three strains of bacteria adapted to utilize glyphosate herbicide (GP) under laboratory ...conditions. Significant differences in the uptake of organophosphonates were found in taxonomically close strains possessing similar enzymatic pathways of catabolism of these compounds, which suggests the existence of unknown mechanisms for the regulation of the activity of these enzymes. The effect of adaptation to GP utilization as the sole phosphorus source on the consumption rates of several other structurally different phosphonates was observed in the studied bacteria. New, highly efficient degrading strains that resulted in a GP decomposition of up to 56% after soil application were isolated. Unsolved problems of microbial GP metabolism and trends in further research on the creation of effective preparations for the bioremediation of soils contaminated with organophosphonates are discussed.
The effect of temperature conditions on the formation of copper active sites obtained by solid state ion exchange between copper chloride and H-mordenite zeolite using X-ray absorption spectroscopy ...in near-threshold (XANES) and extended (EXAFS) spectral regions behind the copper
K
-edge measured in in-situ conditions of the reaction at temperatures varying from room temperature to 400°C. The analysis of the spectra performed using direct calculations of Cu
K
-XANES and taking into account anharmonic corrections for Cu
K
-EXAFS fitting enables us to establish that there is no ion exchange up to 200°C and copper remains in the CuCl state. An increase in the temperature higher 200°C leads to the incorporation of copper atoms to the zeolite framework.
The influence of temperature conditions for synthesis on the nearest-neighbor environment of copper atoms in copper–mordenite zeolites produced by solid-phase ion exchange has been investigated. The ...models of the local atomic structure of active copper centers in copper–mordenite zeolite at 300 and 400°C have been established using two complementary techniques: X-ray absorption spectroscopy and density functional theory. It has been found that, at 300°C, the copper atom does not have another one in its nearest-neighbor environment (monocentric model), whereas at 400°C the center contains at least two copper atoms, which form Cu–O–Cu bridges. The structural parameters of Cu–O bonds have been determined.
Experimental neutron and proton single-particle energies in
N
= 12 to
N
= 20 silicon isotopes and data on neutron and proton scattering by nuclei of the isotope
28
Si are analyzed on the basis of the ...dispersive optical model. Good agreement with available experimental data was attained. The occupation probabilities calculated for the single-particle states in question suggest a parallel-type filling of the 1
d
and 2
s
1/2
neutron states in the isotopes
26,28,30,32,34
Si. The single-particle spectra being considered are indicative of the closure of the
Z
= 14 proton subshell in the isotopes
30,32,34
Si and the
N
= 20 neutron shell.
Fucoidan hydrolase inhibitors were discovered for the first time. Metabolites in the aqueous EtOH extract of Fucus evanescens inhibited specifically the activity of enzymes involved in catabolism of ...brown-alga polysaccharides, i.e., fucoidanases (recombinant FFA from the marine bacterium Formosa algae KMM 3553T and PPF from the marine mollusk Patinopecten yessoensis) and glycosidases (recombinant α-L-fucosidase FucFa from F. algae and β-D-glucosidase G-II from the marine mollusk Littorina sitkana). The purified fucophlorethol fraction isolated from this extract inhibited recombinant fucoidanase FFA in the concentration range 10–50 μg/mL.
The research outcomes for the status of cellular immunity of piglets with porcine reproductive and respiratory syndrome (PRRS) under the industrial hog farm conditions are reported. The 92-day-old ...animals were allocated to two experimental groups of clinically healthy piglets and piglets with symptoms of respiratory pathology. The disease etiology was determined based on the results of bacteriological and molecular biological surveys. Lukocyte counts, leukogram patterns, indicators for phagocytosis, T- and B-lymphocyte counts, interleukin 1 beta, tumor necrosis factor, interferon-gamma, and interleukin 10 were determined. In the animals with PRRS manifesting as respiratory pathology, 21.3, 27.1, and 21.3% decreases in counts of segmented neutrophils, eosinophils, and monocytes, respectively, were recorded. A 12.8% increase in the rod neutrophil counts was ascertained. The integrated immunoreactivity indices of white blood cells in the ratios of lymphocytes and eosinophils to monocytes, lymphocytes to eosinophils, lymphocytes to neutrophils, lymphocytes to monocytes, and neutrophils to monocytes increased by 43.5, 53.4, 33.6, 45.7, and 11.1%, respectively. Increases in the absolute and relative counts of T lymphocytes (CD8+) by 50.0 and 27.7%, respectively, and increases in T-lymphocyte counts (CD4+) becoming twofold and 1.4-fold greater corresponded to an increase in the immunoregulatory index by 23.5%. The recorded changes can indicate the activation of a cell link of nonspecific resistance and the formation of adaptive immunity. A 3.9% increase in the IL-1β and especially a 34.8% increase in the IFN gamma were followed by an increase in the activities of absorption and metabolism of neutrophils in the absence of pronounced changes in the TFN-α and IL-10 concentrations in sick piglets. This could indicate a high activity of a cellular link of nonspecific immunity focused on the inactivation and elimination of a pathogen.
New polymer nanocomposites containing iron oxide nanoparticles stabilized with a biocompatible copolymer of 1-vinyl-1,2,4-triazole with
N
-vinylpyrrolidone were produced. The synthesis was conducted ...using the method of chemical reduction of iron ions with hydrazine hydrate in an aqueous medium in the presence of a polymer matrix. The ESR spectroscopy data showed that the core—shell type nanoparticles were obtained. The core generally consistsed of zero-valence iron coated with an oxide shell. According to the data of transmission electron microscopy, the obtained polymer nanocomposites consisted of nanoparticles of mainly spherical shape with a diameter from 1 to 14 nm. Aggregates formed from individual stabilized nanoparticles of up to 75 nm in size (in most cases) were also observed. These aggregated particles were found to self-organize and form branched chains. Nanocomposites were characterized by a different particle-size distribution, which was determined by the initial ratio of the copolymer and the precursor of iron nanoparticles.
