Low Molecular Weight Fraction Research Articles

The novel immunomodulatory biologic LMWF5A for pharmacological attenuation of the \u201ccytokine storm\u201d in COVID-19 patients: a hypothesis

BackgroundA common complication of viral pulmonary infections, such as in the ongoing COVID-19 pandemic, is a phenomenon described as a “cytokine storm”. While poorly defined, this hyperinflammatory response results in diffuse alveolar damage. The low molecular weight fraction of commercial human serum albumin (LMWF5A), a novel biologic in development for osteoarthritis, demonstrates beneficial in vitro immunomodulatory effects complimentary to addressing inflammation, thus, we hypothesize that LMWF5A could improve the clinical outcomes of COVID-19 by attenuating hyperinflammation and the potential development of a cytokine storm.Presentation of the hypothesisA variety of human in vitro immune models indicate that LMWF5A reduces the production of pro-inflammatory cytokines implicated in cytokine storm associated with COVID-19. Furthermore, evidence suggests LMWF5A also promotes the production of mediators required for resolving inflammation and enhances the barrier function of endothelial cultures.Testing the hypothesisA randomized controlled trial, to evaluate the safety and efficacy of nebulized LMWF5A in adults with Acute Respiratory Distress Syndrome (ARDS) secondary to COVID-19 infection, was developed and is currently under review by the Food and Drug Administration.Implications of hypothesisIf successful, this therapy may attenuate the cytokine storm observed in these patients and potentially reduce mortality, increase ventilation free days, improve oxygenation parameters and consequently lessen the burden on patients and the intensive care unit.ConclusionsIn conclusion, in vitro findings suggest that the immunomodulatory effects of LMWF5A make it a viable candidate for treating cytokine storm and restoring homeostasis to the immune response in COVID-19.

Development of a Methodology Using GPC-ICP HR MS for Analysis of the Adsorption of Asphaltene Aggregates on SiO2 Nanoparticles

The aggregation and adsorption of asphaltenes is of great interest due to their negative effects on the oil industry. Asphaltenes form aggregates, even at low concentrations, producing groups of molecules with different molecular weights in equilibrium. Using GPC ICP HR MS, the different molecular weight fractions are separated. By monitoring the signals of S, V, and Ni ions, typical mass profiles are obtained. The V profile of asphaltene in toluene shows three zones corresponding to low, medium, and high molecular weight fractions in equilibrium. The present study describes the development of a method to study the adsorption of asphaltenes on SiO2 nanoparticles using GPC-ICP HR MS. Samples of asphaltenes in toluene were analyzed before and after adsorption onto nanoparticles (NPs). At low concentrations, the adsorption of larger aggregates predominates. The adsorption onto NPs increases the proportion of vanadium in the low molecular weight fraction of the solution.

Copper(I)‐catalyzed azide‐alkyne cycloaddition‐assisted polymerization of linear glucose‐derived co/polymers

AbstractThe synthesis of linear and controllable oligomers and polymers using sugar‐derived monomers is still highly challenging. Herein, we present a method allowing the linear polymerization of a bifunctional glucose derivative as monomer, which contained an azide group at C1 and a propargyl group at C4 position of the glucose ring. The reaction conditions were optimized by grafting the monomer onto the surface of silica nanoparticles (SiNPs) and at the end‐modified polyethylene glycol (PEG). For grafting the surface of SiNPs with the monomer, an azide‐bearing chlorosilane linker was synthesized and introduced onto SiNPs surface. The copper(I)‐catalyzed azide‐alkyne cycloaddition using the glucose‐derived monomer led to the growth of linear triazole‐linked oligosaccharide‐mimics on the surface of SiNPs with a degree of polymerization up to 13 and the formation of cyclic trimers and tetramers in the solution. Furthermore, during polymerization of the monomer at end‐modified PEG, various linear diblock‐copolymers pseudo‐cellulose‐block‐PEG and triblock‐copolymers pseudo‐cellulose‐block‐PEG‐block‐pseudo‐cellulose were obtained. The polymerization reactions expired with nearly complete consumption of the monomer and high yields between 88 and 94% were achieved. Obtained block‐copolymers showed amphiphilic properties that helped to fractionate obtained polymers into lower and higher molecular weight fractions with narrow polymer dispersity Đ.

Degradation of non-oxidizing biocide benzalkonium chloride and bulk dissolved organic matter in reverse osmosis concentrate by UV/chlorine oxidation

Non-oxidizing biocide that is used to inhibit the microorganism growth on RO membrane, are observed to be high concentration and toxic in RO concentrate. The synergistic oxidation process (SOP) of UV/chlorine was investigated to simultaneously reduced the content (60.2 %) and toxicity (57.0 %) of a representative biocide dodecylbenzyldimethylammonium chloride (DDBAC) in real RO concentrate, with a UV fluence 1080 mJ/cm2 and chlorine dose 20 mg/L. Besides eliminating the DDBAC, UV/chlorine reduced the UVA254 and fluorescence of the dissolved organic matters (DOM). The oxidation mechanism was verified to be the radical electrophilic addition rather than the chlorine-electrophilic substitution through the decay of electron-donation moiety and UVA254. As results, high molecular weight fractions of DOM (>2k Da, 79.2 %) was cleaved into low molecular weight fractions (<0.4k Da, 18.4 %) and organic halide was formed. Parallel-factor analysis of the fluorescence components suggested that decomposition of the protein-like fluorophore is most likely to surrogate the biocide removal and organic halide formation compared to other fluorophore components and UVA254. Accordingly, a portable fluorescence probe with 400 nm excitation and 410–600 nm emission wavelengths was developed as an online surrogate for the DDBAC removal and organic halide formation.

Assessing Redox Properties of Natural Organic Matters with regard to Electron Exchange Capacity and Redox-Active Functional Groups

Redox processes in groundwater play an important role in bioavailability, toxicity, and mobility of redox-active elements and contaminants. A recent study has demonstrated that low-molecular-weight fraction (LMWF) of humic substances with great number of redox-active functional groups (RAFGs) exhibits great reducing capacity. However, whether LMWF of natural organic matter (NOM) exhibits high redox capacity still remains unclear. Therefore, this study extracted Pahokee peat NOM (PPNOM) and Leonardite NOM (LNOM) from soils, and then LMWFs in these NOMs were collected using a dialysis method. Electron exchange capacities (EEC) and RAFGs of LMWF NOMs at different Eh were analyzed using a novel electrochemical method and a three-dimensional excitation emission fluorescence (3DEEM) spectroscopy. We found that the reducing capacity in LMWF PPNOM was approximately 5-6 times higher than the bulk NOM, while only 7.8% LMWF PPNOM was accounted for in the bulk NOM. An increasing in EEC (EAC + EDC, where EAC is the electron accepting capacity and EDC is the electron donating capacity) of LMWF PPNOM and LNOM with Eh reduced from −0.49 V to −0.69 V. Additionally, an obvious increase in fluorescent intensities of quinone-like fluorophores before and after being reduced LMWF LNOM is responsible for high EAC of LMWF LNOM. These findings provide a better understanding of relationship between RAFGs Eh in LMWF of NOM, further helping in predicting and protection of groundwater environment and fate of transformation and transport for redox-active contaminants in groundwater.

Исследование протеиновых фракций высокотемпературных гидролизатов из голов копченой кильки

The authors study three fractions obtained as a result of hydrolysis of smoked sprat heads (under temperature of 130oC and presser of 0.25 MPa) – fat, protein water-soluble, and protein-and-mineral ones. Waste from sprat production of two fish canning complexes of the Kaliningrad Region - “RosCon” and “Kolkhoz for the Motherland” - was used as raw material. Hydrolysis was carried out in an aqueous medium in two ways - with preliminary separation of fat and without this operation. The protein fraction was sublimated and its quantitative and qualitative indices were examined - mass yield, solubility, chemical composition and molecular fractional composition of the obtained peptide fractions were determined. The output of sublimated protein fractions is practically independent of the type of raw material and the method of pre-treatment and is 6.47.9% of the mass of raw materials. The chemical composition of protein fractions varies widely in terms of fat (1.4–8.3%), minerals (9.8–13.4%) and proteins (72.1–80.2%). The solubility of the peptide fractions ranged from 91-98%. The molecular weight assessment results showed a high content of a low molecular weight fraction of peptides with an MM of less than 10 kDa in all experimental samples (about 38%). This indicates a high digestibility and biological value of the obtained peptide compositions. Sublimated peptide compositions had typical organoleptic characteristics, pleasant aroma and taste of smoked fish. &#x0D; Ключевые

Molecular weight-dependent heterogeneities in photochemical formation of hydroxyl radical from dissolved organic matters with different sources

Dissolved organic matter (DOM) is ubiquitous in aquatic ecosystem and characterized by a wide range of molecular weight (MW) distribution. In this study, a total of nine bulk DOM samples, including five International Humic Substances Society (IHSS) standards and four naturally collected samples, were fractionated into low MW (LMW-, <1 kDa) and high MW (HMW-, 1 kDa~0.45 μm) fractions, with MW-dependent heterogeneities in photochemical formation of hydroxyl radical (HO) was investigated. The formation rate of HO (RHO) for the bulk samples were 4.60–7.27 × 10−12 M/s/mg-C/L for IHSS standards and 4.63–7.66 × 10−12 M/s/mg-C/L for naturally collected samples. Regardless of sample types, the LMW fraction was found to exhibit generally higher RHO values than the HMW counterparts. For IHSS standards, the RHO decreased from 4.68–8.46 × 10−12 M/s/mg-C/L for LMW fraction to 3.67–6.66 × 10−12 M/s/mg-C/L for HMW fraction, and for naturally collected samples, the value of RHO decreased from 5.21–12.04 × 10−12 M/s/mg-C/L for LMW fraction to 3.25–6.49 × 10−12 M/s/mg-C/L for HMW counterpart. A positive correlation between the net RHO and the normalized intensities of fluorescent peak [Em/Ex: (400–500)/(230–250) nm] was found, showing that the HO formation was strongly coupled to the abundance of humic-like substances. The results indicate that aquatic DOM is an important pool for HO formation, and characterization of MW distribution rather than average MW is thus required to explain the DOM-induced formation potential of HO.

Characteristics of microplastic polymer-derived dissolved organic matter and its potential as a disinfection byproduct precursor

Although there are numerous studies concerning the occurrence of microplastics (MP) in the environment and its impact on the ecosystem, dissolved organic matter (DOM) leached from MP (MP-DOM) has received little attention, and its characteristics have been rarely examined. It is presumed that the DOM leaching from plastics could be accelerated when plastics lost their protective additives during their transport and weathering processes in aquatic systems. In this study, two additive-free MPs (or micro-sized plastic polymers) were leached in artificial freshwater under UV irradiation and dark conditions. The leached DOM was characterized by typical analyses for naturally occurring DOM (N-DOM) such as dissolved organic carbon (DOC), size exclusion chromatography (SEC), and Fourier-transform infrared spectroscopy (FTIR). The potential to generate trihalomethanes (THMs), a well-known environmental impact of N-DOM, was also explored for the DOM with plastic origins for the first time. The leaching results demonstrated that UV irradiation promoted the leaching of DOM from the plastic polymers with an amount corresponding to ∼3% of the total mass of the polymers. The leached amounts were much greater than those previously reported using commercial plastics which presumably contained protective additives. The SEC results revealed that, different from typical aquatic N-DOM, MP-DOM is mostly composed of low molecular weight fractions <350 Da. For the two polymer types (polyethylene and polypropylene), the MP-DOM exhibited a high potential to form THMs upon chlorination, which was comparable to those of typical aquatic N-DOM. This study highlighted an overlooked contribution of UV irradiation to the DOM leaching from additive-free plastics and the potential risk of MP-DOM to produce toxic disinfection byproducts (DBPs) upon chlorination.

Silver Composites of Ultradisperse Polytetrafluoroethylene and Its Fractions in Supercritical Carbon Dioxide: Synthesis and Structural Study

Ultradisperse polytetrafluoroethylene is separated into fractions soluble and insoluble in supercritical carbon dioxide. The initial polymer and its soluble and insoluble fractions are impregnated with silver(I) (1,5-cyclooctadiene)-1,1,1,5,5,5-hexafluoroacetylacetonate in supercritical carbon dioxide solution for 6.6 h under thermodynamic conditions at 65°С and 8 MPa followed by reduction of the metal in an atmosphere of hydrogen for 6 h at 65°С and 1.2 MPa. According to X-ray fluorescence analysis, the content of the metal attains 2.4 wt %. Ag-polymer composites are studied by X-ray fluorescence spectroscopy, transmission electron microscopy, small-angle X-ray scattering, and X-ray photoelectron spectroscopy. It is shown that silver in the form of nanoparticles with a size of 1.0–7.5 nm is localized largely in the soluble low molecular weight fraction.

Live Neuron High-Content Screening Reveals Synaptotoxic Activity in Alzheimer Mouse Model Homogenates

Accurate quantification of synaptic changes is essential for understanding the molecular mechanisms of synaptogenesis, synaptic plasticity, and synaptic toxicity. Here we demonstrate a robust high-content imaging method for the assessment of synaptic changes and apply the method to brain homogenates from an Alzheimer’s disease mouse model. Our method uses serial imaging of endogenous fluorescent labeled presynaptic VAMP2 and postsynaptic PSD95 in long-term cultured live primary neurons in 96 well microplates, and uses automatic image analysis to quantify the number of colocalized mature synaptic puncta for the assessment of synaptic changes in live neurons. As a control, we demonstrated that our synaptic puncta assay is at least 10-fold more sensitive to the toxic effects of glutamate than the MTT assay. Using our assay, we have compared synaptotoxic activities in size-exclusion chromatography fractioned protein samples from 3xTg-AD mouse model brain homogenates. Multiple synaptotoxic activities were found in high and low molecular weight fractions. Amyloid-beta immunodepletion alleviated some but not all of the synaptotoxic activities. Although the biochemical entities responsible for the synaptotoxic activities have yet to be determined, these proof-of-concept results demonstrate that this novel assay may have many potential mechanistic and therapeutic applications.

Advanced treatment of bio-treated Chinese patent medicine wastewater using ozone/peroxymonosulfate-upflow biological aerated filter

The advanced treatment of biotreated Chinese patent medicine wastewater (BCPMW) was urgently necessitated to meet the strictest wastewater discharge standard. In the present study, combined ozone/peroxymonosulfate oxidation and upflow biological aerated filter process (O3/PMS-UBAF) significantly integrated advantages of O3/PMS oxidation and UBAF, and has been demonstrated to be very effective in the advanced treatment of BCPMW. For dissolved organic matter (DOM) in BCPMW, O3/PMS oxidation efficiently degraded higher molecular weight (MW) fractions and non-biodegradable fractions. In addition, O3/PMS oxidation not only increased the overall removal of DOM but also enhanced the biodegradation rate of DOM. Therefore, the beneficial effect of O3/PMS oxidation may mainly be due to the special effect of increased biodegradability and the generalized effect on DOM. Finally, the results also indicated that compared with UBAF alone, O3/PMS-UBAF not only promoted the removal of low MW fractions (<3kDa) but also inhibited the formation of higher MW fractions (3–10 kDa) that was generated by UBAF alone.

Fucoidan Inhibition of Osteosarcoma Cells Is Species and Molecular Weight Dependent.

Fucoidan is a brown algae-derived polysaccharide having several biomedical applications. This study simultaneously compares the anti-cancer activities of crude fucoidans from Fucus vesiculosus and Sargassum filipendula, and effects of low (LMW, 10–50 kDa), medium (MMW, 50–100 kDa) and high (HMW, >100 kDa) molecular weight fractions of S. filipendula fucoidan against osteosarcoma cells. Glucose, fucose and acid levels were lower and sulphation was higher in F. vesiculosus crude fucoidan compared to S. filipendula crude fucoidan. MMW had the highest levels of sugars, acids and sulphation among molecular weight fractions. There was a dose-dependent drop in focal adhesion formation and proliferation of cells for all fucoidan-types, but F. vesiculosus fucoidan and HMW had the strongest effects. G1-phase arrest was induced by F. vesiculosus fucoidan, MMW and HMW, however F. vesiculosus fucoidan treatment also caused accumulation in the sub-G1-phase. Mitochondrial damage occurred for all fucoidan-types, however F. vesiculosus fucoidan led to mitochondrial fragmentation. Annexin V/PI, TUNEL and cytochrome c staining confirmed stress-induced apoptosis-like cell death for F. vesiculosus fucoidan and features of stress-induced necrosis-like cell death for S. filipendula fucoidans. There was also variation in penetrability of different fucoidans inside the cell. These differences in anti-cancer activity of fucoidans are applicable for osteosarcoma treatment.

Physicochemical properties and aroma profiles of flaxseed proteins extracted from whole flaxseed and flaxseed meal

The aim of this study was to determine the structural and functional properties, and aroma profiles of flaxseed proteins extracted from golden whole flaxseed (WF) and flaxseed meal (FM). Results showed that two kinds of proteins differed significantly in terms of extraction and protein recovery yields, purities, as well as molecular and structural properties. Flaxseed proteins obtained from WF and FM reached different purities of isolate (FPI) and concentrate (FPC), respectively. Both SDS–PAGE and size exclusion chromatography (SEC-HPLC) results suggested that FPC consisted of a larger proportion of low molecular weight fractions with greater heterogeneity than FPI. The isoelectric point (IEP) of the two proteins was significantly different, being pH 4.2 and 3.0 for FPI and FPC, respectively. This was because of the presence of mucilage in FPC. Both proteins showed the high solubility (>90%) at alkaline conditions (pH > 7.0) and the lowest solubility (<10%) near individual IEP. FPI presented higher foaming capacity than FPC at both neutral (pH 7.0) and acidic pH (pH 3.5) while FPC exhibited higher thermal stability than FPI. Both flaxseed proteins presented overall neutral to positive flavors and FPC exclusively contained (Z)-3-hexen-1-ol, 1-octen-3-ol, and (E)-3-octen-2-one, which can be used to differentiate FPC from FPI.

Adsorption of cyanobacterial extracellular polymeric substance on colloidal particle: Influence of molecular weight.

Cyanobacterial extracellular polymeric substances (EPSs) in aquatic environments are easily adsorbed onto colloidal particles, whereas the adsorption behavior as affected by molecular weight (MW) properties remained unknown till now. Herein, the bulk cyanobacterial EPS matrix (<0.45μm) was fractionated into high MW (HMW-, 1kDa~0.45μm) and low MW (LMW-, <1kDa) fractions, with MW-dependent adsorption heterogeneities onto TiO2 colloids exploring through batch experiment, UV-Vis and fluorescence spectroscopy, and two dimensional Fourier transform infrared correlation spectroscopy (2D-FTIR-COS). About two-thirds of total organic matters within bulk EPS matrix were distributed in the HMW fraction, leaving one-third in the LMW fraction. Compared to LMW-EPS, the HMW counterpart exhibited higher aromaticity and richness of autochthonous protein-like substances, showing evident MW-dependent differences in abundance and composition. The adsorption capacity based on the measurement of total abundance, UV-Vis and fluorescent spectra all decreased in sequence of HMW->Bulk>LMW-EPS, demonstrating obvious MW-dependent adsorption heterogeneities. During adsorption, the values of SUVA254 in residual supernatants exhibited an initial decrease followed by gradual increase for all samples, suggesting that the preferentially adsorbed aromatic substances can be subsequently replaced by the non-aromatic moieties. 2D-FTIR-COS further revealed that the carboxylic groups of proteins were preferentially adsorbed onto colloidal surface, followed by the CC functional groups and then the CH groups of polysaccharides, which accounted for the variations of SUVA254 values in the supernatants. This study demonstrated that the adsorption behavior of EPS matrix was highly MW-dependent, and detailed characterization on size fractionation is thus needed in future studies.

Covalent Protein-Polyphenol Bonding as Initial Steps of Haze Formation in Beer

Beer subjected to forced aging by five (Medium) or ten (High) heat/chill cycles (60 °C 48 h/0 °C 24 h) showed increased turbidity from 5.4 ± 0.4 EBC units without forced aging to 12.9 ± 0.7 and 48 ± 2 EBC units for Medium and High forced aged beers, respectively. The particle size diameter increased from 100–200 nm to 10–30 µm. The colloidal changes were associated with modifications of the low molecular weight fraction (∼1 kDa), which were found to increase in the soluble part of the beer as identified by size exclusion chromatography. Polyphenol analyses by liquid chromatography and mass spectrometry showed significant losses of gallic acid, hydroxyphenyllactic acid, salicylic acid, chlorogenic acid, vanillic acid, epicatechin, pyrocatechuic acid, ferulic acid, and luteolin during the forced aging, indicating that these phenolic compounds took part in the colloidal changes, proposedly upon polymerization into tannins. Gel electrophoresis coupled with staining by nitroblue tetrazolium indicated polyphenol modification of all proteins and especially LTP1 (lipid transfer protein 1). It is proposed that the di- and tri-hydroxyl phenolic compounds upon oxidation to quinones react with protein nucleophiles of especially LTP1 to generate the initial covalent bonds, which eventually leads to larger insoluble permanent haze particles.

Antihypertensive Effects of Virgin Olive Oil (Unfiltered) Low Molecular Weight Peptides with ACE Inhibitory Activity in Spontaneously Hypertensive Rats

The low molecular weight peptide composition of virgin olive oil (VOO) is mostly unknown. We hypothesised that unfiltered VOO could possess low molecular weight peptides with antihypertensive activity. We produced unfiltered VOO and obtained a water-soluble peptide extract from it. The peptides were separated by size-exclusion using fast protein liquid chromatography, and the low molecular weight fraction was analysed by nanoscale liquid chromatography-Orbitrap coupled with tandem mass spectrometry and de novo sequencing. We selected 23 peptide sequences containing between 6 and 9 amino acids and molecular masses ranging 698–1017 Da. Those peptides were chemically synthesised and their angiotensin-converting enzyme (ACE) inhibitory activity was studied in vitro. Seven peptides showed a strong activity, with half maximal inhibitory concentration (IC50) <10 µm. The antihypertensive effects of the four most active synthesised ACE inhibitor peptides were studied in spontaneously hypertensive rats (SHR). Acute oral administration of synthetic peptides RDGGYCC and CCGNAVPQ showed antihypertensive activity in SHR. We conclude that unfiltered VOO naturally contains low molecular weight peptides with specific ACE inhibitory activity and antihypertensive effects in SHR.

Evaluation of Probiotic Properties and Prebiotic Utilization Potential of Weissella paramesenteroides Isolated From Fruits.

Weissella paramesenteroides has gained a considerable attention as bacteriocin and exopolysaccharide producers. However, potential of W. paramesenteroides to utilize different prebiotics is unexplored area of research. Fruits being vectors of various probiotics, five W. paramesenteroides strains, namely, FX1, FX2, FX5, FX9, and FX12, were isolated from different fruits. They were screened and selected based on their ability to survive at pH2.5 and in 1.0% sodium taurocholate, high cell surface hydrophobicity, mucin adhesion, bile-induced biofilm formation, antimicrobial activity (AMA) against selected enteropathogens, and prebiotic utilization ability, implicating the functional properties of these strains. In vitro safety evaluation showed that strains were susceptible to antibiotics except vancomycin and did not harbor any virulent traits such as biogenic amine production, hemolysis, and DNase production. Based on their functionality, two strains FX5 and FX9 were selected for prebiotic utilization studies by thin layer chromatography (TLC) and short-chain fatty acids (SCFAs) production by high performance liquid chromatography. TLC profile evinced the ability of these two strains to utilize low molecular weight galactooligosaccharides (GOS) and fructooligosaccharides (FOS), as only the upper low molecular weight fractions were disappeared from cell-free-supernatants (CFS). Enhanced β-galactosidase activity correlated with galactose accumulation in residual CFS of GOS displayed GOS utilization ability. Both the strains exhibited AMA against E. coli and Staph. aureus and high SCFAs production in the presence of prebiotic, suggesting their synbiotic potential. Thus, W. paramesenteroides strains FX5 and FX9 exhibit potential probiotic properties with prebiotic utilization and can be taken forward to evaluate synergistic synbiotic potential in detail.

Extraction Optimization and Evaluation of the Antioxidant and α-Glucosidase Inhibitory Activity of Polysaccharides from Chrysanthemum morifolium cv. Hangju

In order to evaluate the antioxidant and α-glucosidase activities of polysaccharides from Chrysanthemum morifolium cv. Hangju (CMPs), the response surface methodology was applied to optimize the parameters for extraction progress of CMPs by ultrasound, with heat reflex extraction (HRE) performed as the control. The difference in the physicochemical properties of polysaccharides obtained by the two methods were also investigated. The maximum yields (8.29 ± 0.18%) of polysaccharides extracted by ultrasonic assisted extraction (UAE) were obtained under the optimized conditions of ultrasonic power 501 W, extraction time 19 min, and ratio of liquid-to-raw material 41 mL/g. Polysaccharides extracted by UAE possessed lower protein contents (2.56%) and higher uronic acids contents (7.08%) and low molecular weight fractions than that by HRE. No significant differences were found in monosaccharide composition and Fourier transform infrared (FT-IR) spectra of polysaccharides extracted by UAE and HRE, while polysaccharides by UAE possessed stronger antioxidant and α-glucosidase inhibitory activities. Therefore, UAE was an efficient way to obtain CMPs.

Toxicological effects of bioactive peptide fractions obtained from Bothrops jararaca snake venom on the structure and function of mouse seminiferous epithelium.

Background:Pathogenesis of Bothrops envenomations is complex and despite numerous studies on the effects of this snake venom on various biological systems, relatively little is known about such effects on the male reproductive system. In the present study, the toxicological outcomes of the low molecular weight fraction (LMWF) of B. jararaca snake venom - containing a range of bioactive peptides - were investigated on the dynamics and structure of the seminiferous epithelium and 15P-1 Sertoli cells viability.Methods:LMWF (5 µg/dose per testis) venom was administered in male Swiss mice by intratesticular (i.t.) injection. Seven days after this procedure, the testes were collected for morphological and morphometric evaluation, distribution of claudin-1 in the seminiferous epithelium by immunohistochemical analyses of testes, and the nitric oxide (NO) levels were evaluated in the total extract of the testis protein. In addition, the toxicological effects of LMWF and crude venom (CV) were analyzed on the 15P-1 Sertoli cell culture.Results:LMWF induced changes in the structure and function of the seminiferous epithelium without altering claudin-1 distribution. LMWF effects were characterized especially by lost cells in the adluminal compartment of epithelium (spermatocytes in pachytene, preleptotene spermatocytes, zygotene spermatocytes, and round spermatid) and different stages of the seminiferous epithelium cycle. LMWF also increased the NO levels in the total extract of the testis protein and was not cytotoxic in concentrations and time tested in the present study. However, CV showed cytotoxicity at 10 μg/mL from 6 to 48 h of treatment.Conclusions: The major finding of the present study was that the LMWF inhibited spermatozoa production; principally in the spermiogenesis stage without altering claudin-1 distribution in the basal compartment. Moreover, NO increased by LMWF induce open of complexes junctions and release the germ cells of the adluminal compartment to the seminiferous tubule.

Purification and removal of the low molecular weight fraction of polyDADMAC reduces N-nitrosodimethylamine formation during water treatment

Residual organics in cationic polymer contribute disproportionately to NDMA formation, but can be removed through polymer purification.