Search

Small-aroma chicken with a high protein content, is widely distributed in the mountainous area of Yunnan-Guizhou Plateau, China. In this work, three novel ACE-inhibitory peptides, Leu-Thr-Glu-Lys-Val-Val-Phe (LTQKVVF), Leu-Asp-Asp-His-Phe-Leu (LDDHFL), and Val-Pro-Gly-Pro-Glu-Pro-Lys-Pro (VPGPEPKP), were prepared from the Small-Aroma Chicken breast. The purification and identification protocol employed comprised ion-exchange chromatography, gel filtration chromatography, reverse phase-high performance liquid chromatography (RP-HPLC), and nano liquid chromatography-electrospray ionization–tandem mass (Nano-LC-ESI–MS/MS). Compared with VPGPEPKP and VPGPEPKP, LTQKVVF displayed noticeable ACE inhibitory activity, with IC 50 values of 189.34 μM. What's more, the Lineweaver-Burk plots revealed peptides LTQKVVF and LDDHFL acted as the mixed-competitive inhibitor while VPGPEPKP inhibited ACE in a manner similar to uncompetitive inhibition. The binding free energies of LTQKVVF, LDDHFL, and VPGPEPKP for ACE were −8.1 kcal/mol, −8.6 kcal/mol, and −9.6 kcal/mol, respectively. The strong inhibition of ACE by VPGPEPKP may be attributed to the interaction of hydrogen bonds, alkyl, and pi-alkyl, which formed by crucial residues of ACE. [Display omitted] • Three novel peptides were characterized from small-aroma chicken. • The peptides exhibited inhibition activity on angiotensin converting enzyme (ACE). • Lineweaver Burk plots was used to identify the inhibition mode of peptides. • The interactions between peptides and ACE were simulated by molecular docking. [ABSTRACT FROM AUTHOR]

The wild, edible mushroom Rugiboletus extremiorientalis has an excellent taste and also medicinal effects, and is very popular in China. In this study, hot water extraction is used to isolate polysaccharides from R. extremiorientalis fruiting bodies, and response surface methodology is used to optimize the extraction conditions in terms of temperature, liquid–solid ratio, and time. The crude extract (REP) is purified in turn by DEAE‐52 chromatography and Sephadex G‐100 chromatography, resulting in three fractions (REP‐1, REP‐2, and REP‐3) with recovery rates of 16.7%, 57.65%, and 6.63%, respectively. In vitro antioxidant activity is highest for REP‐2, and the subsequent research is therefore focused on that fraction. High‐performance liquid chromatography reveals that REP‐2 is comprised of fucose, arabinose, galactose, glucose, xylose, and mannose. Fourier‐transform infrared spectroscopy of REP‐2 indicates the presence of functional groups typical for polysaccharides. High‐performance gel filtration chromatography indicates the REP‐2 has a molecular weight of 342.4 kDa. The results of this study provide a foundation for future research concerning the antioxidant activity of polysaccharides in R. extremiorientalis. [ABSTRACT FROM AUTHOR]

Dendrobium officinale Kimura et Migo (D. officinale) is used as herbal medicine and new food resource in China, which is nontoxic and harmless, and can be used as common food. Polysaccharide as one of the main bioactive components in D. officinale , mainly composed of glucose and mannose (Man p : Glc p = 2.01:1.00-8.82:1.00), along with galactose, xylose, arabinose, and rhamnose in different molar ratios and types of glycosidic bonds. Polysaccharides of D. officinale exhibit a variety of biological effects, including immunomodulatory, anti-tumor, gastro-protective, hypoglycemic, anti-inflammatory, hepatoprotective, and vasodilating effects. This paper presents the extraction, purification, structural characteristics, bioactivities, structure-activity relationships and analyzes gaps in the current research on D. officinale polysaccharides. In addition, based on in vitro and in vivo experiments, the possible mechanisms of bioactivities of D. officinale polysaccharides were summarized. We hope that this work may provide helpful references and promising directions for further study and development of D. officinale polysaccharides. • D. officinale polysaccharides are purified by anion exchange and gel permeation chromatography. • D. officinale polysaccharides possess diverse structures and configurations. • D. officinale polysaccharides exhibit diverse biological activities. • Structure-activity relationship of D. officinale polysaccharides should be addressed in future studies. [ABSTRACT FROM AUTHOR]

Platycodonis Radix is widely used as homology of medicine and food in China; polysaccharides are thought to be one of its functional constituents. In this study, a pectic polysaccharide, PGP-I-I, was obtained from the root of the traditional medicine plant Platycodon grandiflorus through ion exchange chromatography and gel filtration. This was characterized being mainly composed of 1,5-α-L-arabinan and both arabinogalactan type I (AG-I) and II chains linked to rhamnogalacturonan I (RG-I) backbone linked to longer galacturonan chains. In vitro bioactivity study showed that PGP-I-I could restore the intestinal cellular antioxidant defense under the condition of hydrogen peroxide (H 2 O 2) treatment through promoting the expressions of cellular antioxidant genes and protect against oxidative damages. • A pectic polysaccharide PGP-I-I was purified from Platycodon grandiflorus. • PGP-I-I contains long HG regions and AG side chains, with Mw of 27.9 kDa. • PGP-I-I promotes antioxidant defense of the intestinal porcine epithelial cells in vitro. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the morphological characteristics of different brands of lentinan injections produced in China using atomic force microscopy (AFM) and their relationship to immunological activity. Based on AFM imaging, chain height could be used as characterizing the conformation of lentinan, and the heights of 95 % confidence interval for triple, double and single helix were 1.746 ± 0.039 nm, 1.564 ± 0.037 nm and 1.243 ± 0.031 nm, respectively, which were calculated using self-developed MATLAB protocol. AFM characters and their immunological activity of different lentinan injection were compared. In detail, two parameters, triple helix ratio 51.3 % and adhesion force 800 pN, of Jinling (JL) lentinan injection are much higher than samples of other four manufacturers. In addition, immunological activity of JL lentinan injection is also significantly higher than Yineng's. High performance size exclusion chromatography (HPSEC) profiles of different lentinans were also compared, and the data were in accordance with those from AFM. Molecular weight accumulation curves could be used for evaluation of quality consistence of different batches of lentinan from same manufacturer and/or different manufacturers. The results showed that quality consistence of lentinan from different manufactures is poor, which should be greatly improved. [Display omitted] • The conformation of lentinan was investigated and quantitatively characterized using AFM. • The morphology and immune activity of different lentinan injections were compared. • The conformation of lentinan has closed relationship to its activity. • Triple helix is the major active conformation of lentinan. [ABSTRACT FROM AUTHOR]

Nitraria sibirica Pall is a traditional Chinese medicine (TCM) and rich in polysaccharides. The Xinjiang district of China is rich in Nitraria sibirica resources. Numerous preparations containing Nitraria sibirica have been used to treat various diseases in TCM. However, the relevant studies lack systematicness in both chemistryand pharmacodynamics, and the effective substances are still not clear. They are facing the crisis of "insufficient scientific interpretation of drug theory" and "unclear sourceof medicinal materials", which leads to the lack of scientific methods and indicators for the quality control of Nitraria sibirica or its preparations. Therefore, it is essential to systematically study genuine medicinal materials to solve the problems such as the confusion of medicinal materials, the lack of related literature, andtheoretical basis. In this paper, the isolation and bioactivity evaluation of polysaccharides from the Nitraria sibirica medicinal material was systematically discussed, which laid an important basis for elucidating the theoretical basis of its medicinal substances. The main findings are as follows: The ultrasonic-assisted extraction of Nitraria sibirica polysaccharides (NSP) was optimized by response surface methodology. The results showed that the optimum conditions were liquidsolid ratio 33 mL/g, ultrasonic power 430 W, ultrasonic temperature 60 ℃ and ultrasonic time 70 min. At this condition, the yield of NSP wasup to 14.63 ± 0.21%. Four homogenous polysaccharides, namely NSP-a, NSP-b1, NSPb2, and NSP-c, were obtained through purifying by AB-8 macroporous resin, dialysis, DEAE-650M anion exchange, and Sephadex G-150 gel permeation chromatography. Among them, NSP-a was a neutral polysaccharide, and acidic polysaccharides for the others, with the purity 91.12 ± 1.15%, 94.02 ± 2.18%, 95.71 ± 2.56%, 94.30 ± 0.87%, respectively. [ABSTRACT FROM AUTHOR]

A capsular polysaccharides (CPS) producer Bacillus velezensis SN-1 (B. velezensis SN-1) was isolated in Da-jiang, China. We used ultrasonic extraction to obtain CPS from a culture of B. velezensis SN-1 at a yield of 755 mg/L. Using gel permeation chromatography (GPC), CPS was separated into a single peak with a molecular weight of 1.46 × 105 Da. Its structures were characterized by gas chromatography (GC), methylation, Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). The CPS was identified as a polysaccharide with a highly branched main chain of mannose with (1 → 3) connections. Moreover, our results revealed that CPS has the capacity to scavenge DPPH radical, hydroxyl radical, ABTS radical and oxygen radical in a manner that relied on concentration. Anti-neoplastic analysis showed that CPS displayed significant anti-tumor activity towards HepG-2 tumor cells. Above findings indicate that CPS generated by B. velezensis SN-1 may be adapted for use as a natural antioxidant in foodstuffs and as an anti-tumor drug. Unlabelled Image • A purified cell-bound exopolysaccharides (CPS) were extracted from Bacillus velezensis SN-1 in Da-jiang. • The primary structure of CPS was identified by GPC, FT-IR, GC–MS, NMR. • The CPS exhibited potent antioxidant activity in vitro. • The CPS had significant antitumor activities on HepG-2 tumor cells in vitro. [ABSTRACT FROM AUTHOR]

This study concerns total arsenic (TAs) and arsenic species determination in three species of mushrooms collected in Yunnan, China. The purpose of this study was to check concentration level of arsenic in Boletus edulis , Tricholoma matsutake and Suillellus luridus , estimate arsenic bioaccessibility and find out which arsenic species occur in mushrooms to assess if they may pose a threat to human health. An analytical methodology based on ion chromatography (IC) hyphenated to inductively coupled plasma mass spectrometry (ICP-MS) with dynamic reaction cell (DRC) and size exclusion chromatography (SEC) with UV–Vis detection and ICP-DRC-MS detection. Ultrasound assisted extraction (UAE), microwave assisted extraction (MAE) and enzymatic assisted extraction (EAE) were applied. Quantification of As species in extracts was performed by IC/ICP-DRC-MS in the first dimension. Slightly better extraction efficiencies were obtained for MAE (from 75% to 90%) then for UAE. EAE was used for estimation of bioaccessibility by application of a modified BARGE bioaccessibility method (UBM) for in vitro studies. Bioaccessibility values were in the ranges of 73%–102%, 74%–115% and 18%–87% for step 1 (S1), for step 2 (S2) and for step 3 (S3) of EAE, respectively. Extracts obtained after EAE were subjected to SEC-UV-Vis/ICP-DRC-MS analysis as the second dimension. The main signal was obtained in the area of a molecular mass of ∼5 kDa for all mushroom extracts. Monitoring of an 50SO+ ion confirmed that this signal comes from As-protein. In sample of Boletus edulis additional signal occurred which is classified as unknown As-compound. Both signals require identification with another analytical technique. Image 1 • Speciation of As in mushroom samples from Yunnan, China. • Speciation analysis by IEC-ICP-DRC-MS and SEC-UV-Vis/ICP-DRC-MS. • Ultrasound, microwave and enzymatic assisted extraction of arsenic from mushroom samples. • Bioaccessibility of As from mushroom samples using modified BARGE method. [ABSTRACT FROM AUTHOR]

Achyranthes bidentata has been traditionally used in China as a nature remedy for osteoporosis; however, little is known about the osteoprotective effects of its polysaccharides. The crude A. bidentata polysaccharide (AB70) was prepared by hot water extraction- ethanol precipitation method and a homogeneous fructan (ABW70-1) was purified from AB70 by ion-exchange and gel filtration column chromatography. Structural analysis indicated that ABW70-1 was composed of (2 → 1)-linked- β - d -fructofuranosyl (Fru f), (2 → 6)-linked- β - d -Fru f and (2 → 1,6)-linked- β - d -Fru f residues, and terminated with fructose and glucose residue. AB70 treatment for 13 weeks has shown a therapeutic effect on ovariectomized rats by restoring bone mineral content and biomechanical properties of the femur. Moreover, such osteoprotective effects of AB70 on bone mass were accompanied by improving trabecular bone microarchitecture and decreasing serum levels of bone turnover biomarkers. Furthermore, ABW70-1 stimulated the osteogenic differentiation of MC3T3-E1 cells by promoting cell proliferation, ALP activity, mineral nodules formation and the gene expression of Osx , Ocn and Bsp. These results suggest that A. bidentata polysaccharides have a great potential in the prevention and treatment of osteoporosis. Unlabelled Image • Water soluble crude polysaccharide (AB70) was extracted from Achyranthes bidentata. • AB70 improved bone mineral content and biomechanical properties in OVX rats. • A homogeneous fructan, ABW70-1, was purified from AB70. • ABW70-1 stimulated osteogenic differentiation of MC3T3-E1 cells. • ABW70-1 upregulated gene expression of Osx , Ocn and Bsp. [ABSTRACT FROM AUTHOR]

• Three types of asphalt with the largest usage in China were tested. • Rubber# has the best anti-aging performance, followed by SBS# and 70#. • The glass transition temperature and the area ratio of characteristic functional groups increased after aging. • The GPC curve shifts to the macromolecular direction after asphalt aging. To study the effect of thermo-oxidative aging on the physical properties and microstructure of base and modified asphalts, conventional index tests, dynamic shear rheology (DSR), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and gel permeation chromatography (GPC) were performed. The macro-physical indexes and microstructural changes in the asphalt before and after aging were analyzed. The results show that with an increase in the thermal-oxidative aging degree, the penetration degree of asphalt decreases; the softening point increases, and the high-temperature performance improves. Simultaneously, the asphalt consistency and hardness increase. This results in a significant increase in the initial modulus and glass transition temperature, decrease in the shear resistance, and degradation of the low-temperature performance. Rubber-modified asphalt exhibited the highest anti-aging performance, followed by styrene–butadiene–styrene-modified and 70# asphalts. Thermal-oxidative aging did not change the original functional group species; however, the peak area ratio of the sulfoxide and carbonyl functional groups increased significantly. After aging, the overall molecular weight of the asphalt shifted in the macromolecular direction. Weight-average and number-average molecular weights and polydispersity increased. [ABSTRACT FROM AUTHOR]

• The aging HCPMA is combined with hardening of asphalt and degradation of SBS polymer. • The content and molecular weight of SBS polymer decreases during PAV aging. • The addition of high content of SBS polymer can reduce the formation of carbonyl in asphalt. • HCPMA gains better rheological properties with higher SBS content, while economic dosage is 9%. • Compared with SK asphalt, Esso asphalt is more suitable for HCPMA as base asphalt. To meet the high temperature and anti-reveling properties required in open-graded friction course, high content polymer modified asphalt (HCPMA) is gradually widely used in China, but the rheological, chemical and aging characteristic is not clear yet. In this paper, HCPMA with different SBS content and different base asphalt are prepared, and Pressure Aging Vessel (PAV) aging was conducted to simulate the long-term aging condition. The chemical and rheological evaluation of HCPMA before and after aging were tracked with Fourier transform infrared, gel permeation chromatography test, dynamic shear oscillatory test, master curve and multiple stress creep and recovery test. The results show that firstly, the aging of HCPMA is combined with hardening of asphalt and degradation of Styrene–butadiene–styrene (SBS) polymer. Furthermore, the addition of high content of SBS polymer can reduce the formation of carbonyl, but the degradation rate of SBS polymer is not related to the content of SBS or the type of base asphalt. Besides, HCPMA with a higher SBS content will have better rheological properties, but in consideration of economy, 9% is optimum dosage. At last, HCPMA prepared with Esso asphalt as base binder exhibits better rheological properties than HCPMA prepared with SK asphalt. However, the rheology difference reduces with the increase of SBS content and after PAV aging. [ABSTRACT FROM AUTHOR]

Polysaccharides with multiple biological activities and health benefit effects are usually considered as one of the major function components in food and medicine dual purposes Chinese herbs (FMDPCH). With the increasing interest in the utilization of FMDPCH, their quality control is very important for ensuring their safety and efficacy. To date, there is no report focus on the analysis of polysaccharides in FMDPCH. Herein, advanced development for quality control approaches, including sample preparation, separation and fraction, qualitative and quantitative analysis, of polysaccharides in MPDPCH were reviewed and discussed. Especially, discrimination and quantification of polysaccharides, respectively, based on novel saccharide mapping and universal refractive index increment were focused. Besides, the perspective for the characterization of polysaccharides has also been described. [ABSTRACT FROM AUTHOR]

Douchi is a fermented soybean food, which is popular in China. Composition and angiotensin I-converting enzyme-inhibitory activity of Douchi fermented withMucor wutungkiaowere studied in this work. The results showed that the nutritional potency of protein, fat, and soluble polysaccharide was improved in Douchi fermentation. The angiotensin I-converting enzyme-inhibitory activity of Douchi that ripening for 2 weeks showed the highest angiotensin I-converting enzyme-inhibitory activity. Then this sample was purified with Sephadex G-25 gel chromatography, and the amino acids and angiotensin I-converting enzyme-inhibitory activity of the purified fractions were studied. The results suggested that hydrophobic amino acids were assumed to cause the main increase of the angiotensin I-converting enzyme-inhibitory activity in Douchi. [ABSTRACT FROM PUBLISHER]

Although a number of studies have addressed the bioaccumulation of Dechlorane Plus (DP) flame retardant in wildlife, few data are available on terrestrial organisms. This study examined the presence of DP isomers in the muscle tissue of seven terrestrial resident passerine species, i.e., the great tit ( Parus major ), the oriental magpie-robin ( Copsychus saularis ), the red-whiskered bulbul ( Pycnonotus jocosus ), the light-vented bulbul ( Pycnonotus sinensis ), the streak-breasted scimitar babbler ( Pomatorhinus ruficollis ), the long-tailed shrike ( Lanius schach ), and the orange-headed thrush ( Zoothera citrina ), from a national nature reserve located in South China. The ∑DP (sum of syn -DP and anti -DP) concentrations ranged from 1.2 to 104 ng/g lipid weight, with significantly higher levels in insectivorous birds than in omnivorous birds. The overall exposure to DP isomers of the current passerines may be attributed to the intensive release of this pollutant from electronic waste recycling sites and industrial zones in the vicinity of the nature reserve. Species-specific DP isomeric profiles were also found, with significantly greater f anti values (the isomer fractions of anti -DP) in the red-whiskered bulbul and the oriental magpie-robin. Additionally, the f anti values were significantly negatively correlated to ∑DP concentrations for the individual bird samples, suggesting the influence of DP concentrations on the isomeric profiles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pterins were identified as recurring algae-derived humic-like fluorophores. • Redox transformation from H 4 Bip to biopterin occurred during oxygen aeration. • Sunlight induced algal biodegradation and photochemical oxidation of biopterin. • Pterins contributed to the absorbance and fluorescence of algae-laden lake water. • Once released during pre-oxidation, biopterin cannot be removed by coagulation. In this study, we have identified 6-L-biopterins and their glucosides as candidate structures for the consistently occurring algae-derived humic-like fluorophores (Em 440–460 nm) using a combination of fluorescence excitation-emission matrixes, size exclusion chromatography with fluorescence detector and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry. In intact algal cells, biopterins and their glucosides existed mainly as their reduced tetrahydrobiopterin (H 4 Bip) forms, and redox transformation from H 4 Bip to biopterin occurred with the exposure of intracellular algal organic matter to oxygen. During the degradation experiment under simulated natural conditions, light irradiation facilitated the utilization of biopterin by Microcystic aeruginosa and induced the photochemical degradation of 6-L-biopterin to 6-carboxypterin. The concentrations of 6-L-biopterin (without counting any other derivatives) ranged from 0.20 μg/L to 2.78 μg/L in water samples from 5 lakes in China. For an investigated sample from Lake Tai surface water, biopterin and its derivatives contributed to 24.0 ± 1.1% of UV absorbance at 350 nm and 55.5 ± 1.7% of fluorescence at Ex350/Em450 nm of total chromophoric/fluorescent dissolved organic matter (CDOM/FDOM). During water treatment, pre-chlorination of algae-laden water induced the releases of biopterin and its derivatives into water, and the variation of biopterin fluorescence intensity can be used as a surrogate indicator for predicting algal membrane damage. Once released into water, biopterin could not be effectively removed by the conventional coagulation treatment irrespective of coagulant type, dose and water pH. The identification of ubiquitous pterins as candidate structures responsible for "humic-like" fluorophores is conducive to the understanding of the generation, property, behavior and fate of algae-derived CDOM/FDOM in natural and engineered water systems. [ABSTRACT FROM AUTHOR]

China's highway asphalt pavement has entered the stage of major repair, and improving the utilization rate of recycled asphalt pavement (RAP) is the main issue. The key link affecting the performance of recycled asphalt mixtures is the regeneration of aged asphalt, and the effect of the regenerant dosing on the high-temperature performance and viscosity of aged asphalt is the main content to be studied in this research. The aging behavior of asphalt seriously affects the roadworthiness of asphalt mixtures. In this study, we investigated the effect of changes in the microscopic properties of the aged asphalt on its viscosity properties during regeneration using gel permeation chromatography (GPC), Fourier-transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) as well as Brinell viscosity tests. This study simulated asphalt aging by the RTFOT test, and then we obtained an aged asphalt with a needle penetration of 30. We prepared different regenerated asphalts by adding regeneration agent with doses of 2%, 4%, and 6% to the aged asphalt. The results showed that the regeneration agent could effectively reduce the viscosity of the aged asphalt, which can play a positive role in improving the construction and ease of the aged asphalt. Rejuvenation agents affected the aging asphalt sulfoxide and carbon group indices. Moreover, rejuvenation agents can also significantly reduce the intensities of their characteristic functional group indices. The results of the AFM test showed that the increase in the dose of regeneration agent increased the number of the asphalt bee-like structures and decreased the area of individual bee-like structures. The results of the GPC test were consistent with the results of the AFM test, and the increase in the dose of regeneration agent reduced the asphalt macromolecule content. The viscosity properties and microstructure of the aged asphalt changed positively after the addition of the regeneration agent, indicating that the regeneration agent had a degrading and diluting effect on macromolecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • Online cleanup method for simultaneous analysis of PAHs and OH-PAHs in fingernail. • Online GPC-GC–MS/MS enables rapid and sensitive determination of 16 PAHs. • Online SPE-LC-MS/MS allows sensitive and robust quantification of 12 OH-PAHs. • PAHs of 2–4 rings and their hydroxylated metabolites were widely detected. • Nail analysis facilitate non-invasive biomonitoring of PAHs in human. A method was developed for the simultaneous determination of polycyclic aromatic hydrocarbons (PAHs) and their hydroxylated metabolites (OH-PAHs) in human fingernails using liquid–liquid extraction and online purification. After surface decontamination by rinsing with acetone, the fingernails were digested with sodium hydroxide and subjected to liquid–liquid extraction with a mixture of n-hexane and methyl tertbutyl ether. The organic extract was then fractionated using a silica-based solid-phase extraction (SPE) cartridge to obtain a PAH fraction eluted with n-hexane/dichloromethane (v/v, 95:5) and an OH-PAH fraction eluted with dichloromethane/ethyl acetate (v/v, 50:50). The PAH fraction was directly injected into an online gel permeation chromatography-gas chromatography-triple quadrupole tandem mass spectrometry (GPC-GC–MS/MS) system, enabling rapid determination of 16 PAHs. A parallel online SPE liquid chromatography tandem mass spectrometry (LC-MS/MS) method was used to determine 12 OH-PAHs. Validation experiments showed that the recovery of PAH and OH-PAH were within range of 67.4%−105.1% (RSD ≤ 10.1%) and 72.8%−102.3% (RSD ≤ 10.9%), respectively, with limits of quantitation (LOQ) of 0.06–0.8 ng/g and 0.15–3.1 ng/g, respectively. Forty-two human fingernail samples from residents of Southern China were analyzed to establish background PAH and OH-PAH levels in this region. Several PAHs and OH-PAHs were detected, at concentrations of 97.5 to 3,687 ng/g for PAHs and 24.2 to 767 ng/g for OH-PAHs. The dominant homologues were two- and three-ring PAH isomers, notably naphthalene (Nap), fluorene (Flu), and phenanthrene (Phe), as well as the corresponding hydroxylated metabolites 2-OH-Nap, OH-Flu, and OH-Phe. Smoking, consuming barbecued food, and age had no significant effects on PAH exposure, but a larger sample would be required to confirm this finding. The online purification strategy presented here expedites cleanup and purification during analysis of human fingernails and should facilitate non-invasive biomonitoring of PAHs in humans, particularly when analyzing large numbers of samples. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) in wastewater treatment plant (WWTP) effluent threats aquatic environment and challenges engineered aquatic systems. In order to predict its environmental risk and guide the selection of suitable strategy and technology, understanding the removal efficiency and the fate of DOM along the treatment is helpful. Herein, to qualitatively and quantitatively estimate the composition of DOM in a full-scale WWTP in northern China, a combined approach of chromatography and spectroscopy was employed, and the contribution of size-dependent substructure to the global feature of DOM was discussed simultaneously. The results suggest that the WWTP could remove the free proteins of low molecular size by physical treatment with removal ratios of 46.4% and 41.0% for tyrosine and tryptophan, respectively, whereas humic-like and humic-protein complex accumulate in the effluent of treatment with a ratio of 40.6%. Biotreatment is of importance for changing the proportion of different types of DOM, especially for anaerobic tank and the anoxic tank, which results in the increase of humification. Size exclusive chromatography (SEC) coupled with multi emission maps identifies six DOM substructures. Two protein-like DOM were removed by the WWTP, except the composition with the molecular weight ranging from 0.75 to 0.25 kDa, whereas humic-like DOM with whole size range accumulated to varying extent. The standard deviation analysis states that the structure variation of bulk DOM in the WWTP is primarily contributed by the decrease of small-sized proteins and the increase of humic-like DOM. This study presents insight into the fate and behavior of DOM components during the full-scale WWTP treatment and provides guidelines for altering DOM-treating technologies. Besides, innovative strategies suggest using DOM as a resource based on the critical review of previous research. [ABSTRACT FROM AUTHOR]

Chroma is not effectively removed from Vitamin C (VC) wastewater by traditional anaerobic-aerobic treatment. This means current treatment does not meet the strict new discharge standard for VC wastewater in China. However, to date, no studies have investigated the removal of chroma from VC wastewater, or characterized the chromophoric organic matter in wastewater. In this study, choromophoric organic matter in effluent from anaerobic-aerobic treatment of Vitamin C wastewater was characterized using high performance gel permeation chromatography (HPGPC), ultrafiltration, and infrared (IR) and ultraviolet-visible (UV/Vis) spectroscopy. Routine water-quality indices were determined, and indicated that the organic matter in the effluent contained nitrogen. The molecular weight of most organic matter in this effluent was below 1000 Da, while the remainder was between 1000-3000 Da. These compounds are likely biodegradation products of high molecular weight organic matter in the effluent, which are raw materials and byproducts from VC production. IR spectra indicated that the low molecular weight (<1000 Da) organic matter and higher molecular weight (1000-3000 Da) organic matter contain similar major functional groups, including - OH, -NH2, -CO-NH2, -C=O-, and -COO-. The effluent was treated using electrolysis, and UV/Vis spectra of this effluent before and after electrolysis indicated that -C=O is an important chroma group in this effluent. Electrolysis can easily break -C=O, and provides a feasible technology for the advanced treatment of anaerobic-aerobic effluent from VC wastewater treatment. [ABSTRACT FROM AUTHOR]

Abstract: The polysaccharide of Opuntia ficus indica Mill. was isolated by water, and purified by Sephacryl S-400 HR column. The purity of polysaccharide was evaluated by HPLC coupled with gel permeation chromatography. Results showed that the neutral monosaccharide composition of O. ficus indica polysaccharide was rhamnose, arabinose, and glucose in a molar ratio of 1.00:2.98:2.57, with an average molecular weight of about 172,591Da. Further, its antioxidant capacities in vitro were respectively evaluated by the assays of inhibition of pyrogallol autoxidation, scavenging hydroxyl radical, and liver lipid peroxidation inhibiting. The crude water-soluble polysaccharide and purified polysaccharide showed notable free radical scavenging activity and hydroxyl radical-induced liver lipid peroxidation inhibiting ability, suggesting that O. ficus indica polysaccharide may be considered as a potential candidate for the natural antioxidants and possible health-promoting functional foods. [ABSTRACT FROM AUTHOR]

Abstract: A bacteriocin named plantaricin MG produced by Lactobacillus plantarum KLDS1.0391 which was isolated from “Jiaoke”, a traditional, naturally fermented cream from Inner Mongolia in China is reported in this article. Plantaricin MG was purified by ammonium sulfate precipitation followed by sequential gel filtration chromatography and reverse-phase chromatography. Mass spectrometry analysis showed the mass of plantaricin MG to be approximately 2180Da. The bacteriocin showed a broad inhibitory activity against Gram-positive and Gram-negative bacteria including Listeria monocytogenes, Staphylococcus aureus, Salmonella typhimurium and Escherichia coli. The bacteriocin was extremely heat-stable (30min at 121°C) and remained active after incubation at pH 2.0–10.0. It was found to be sensitive to proteolytic enzymes (pepsin, trypsin, papain, α-chymotrypsin, proteinase K, Neutrase and Alcalase). The mode of action of plantaricin MG was identified as bactericidal. [Copyright &y& Elsevier]

• COVID-19's impacts on water quality were first studied with fluorescence technique. • One of the main pollution sources in study water body was identified. • Shutdown & production cutdown of industries due to the pandemic weakened pollution. • Fluorescent component's intensity reduced during the domestic and global pandemic. In 2020, a sudden COVID-19 pandemic unprecedentedly weakened anthropogenic activities and as results minified the pollution discharge to aquatic environment. In this study, the impacts of the COVID-19 pandemic on aquatic environment of the southern Jiangsu (SJ) segment of Beijing-Hangzhou Grand Canal (SJ-BHGC) were explored. Fluorescent component similarity and high-performance size exclusion chromatography analyses indicated that the textile printing and dyeing wastewater might be one of the main pollution sources in SJ-BHGC. The water quality parameters and intensities of fluorescent components (WT-C1(20) and WT-C2(20)) decreased to low level due to the collective shutdown of all industries in SJ region during the Spring Festival holiday and the outbreak of the domestic COVID-19 pandemic in China (January 24th to late February, 2020). Then, they presented a gradual upward trend after the domestic epidemic was under control. In mid-March, the outbreak of the international COVID-19 pandemic hit the garment export trade of China and consequently inhibited the production activities of textile printing and dyeing industry (TPDI) in SJ region. After peaking on March 26th, the intensities of WT-C1(20) and WT-C2(20) decreased again with changed intensity ratio until April 12th. During the study period (135 days), correlation analysis revealed that WT-C1 and WT-C2 possessed homology and their fluorescence intensities were highly positively correlated with conductivity and COD Mn. With fluorescence fingerprint (FF) technique, this study not only excavated the characteristics and pollution causes of water body in SJ-BHGC, but also provided novel insights into impacts of the COVID-19 pandemic on production activities of TPDI and aquatic environment of SJ-BHGC. The results of this study indicated that FF technique was an effective tool for precise supervision of water environment. [ABSTRACT FROM AUTHOR]

Comparison of Salvia miltiorrhiza polysaccharides (SMPs) from different geographical origins in China (Henan, Hebei, Shandong, Sichuan, Shaanxi) was performed using high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID), saccharide mapping based on polysaccharide analysis by using carbohydrate gel electrophoresis (PACE) and combined with principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Based on the results of HPSEC-MALLS/RI, the relative content of SMPs showed a significant difference between different geographical origins, however, the molecular weight of SMPs showed almost no significance. SMPs can be discriminated as five regions after PACE coupled with OPLS-DA models analysis of endo-1,5- α -arabinanase hydrolysates. Moreover, all the PACE fingerprint indicated that 1,4- β -D-Galp, 1,5- α -Araf, 1,4- α -D-GalAp and 1,4- β -D-Glcp linkages existed in SMPs. [ABSTRACT FROM AUTHOR]

new peptide that had anti-oxidant activity and molecular weight 5,000.5 Da according to PAAG data and mass spectrometry was isolated from celery seed using chromatographic methods. [ABSTRACT FROM AUTHOR]

• Polysaccharides from nine species of Polygonatum were firstly compared. • Enzymatic digestion followed by HPGPC saccharide mapping were used. • Polysaccharides from most Polygonatum spp. consisted of pectins and fructans. • Polysaccharides from P. macropodium were mainly composed of fructans. • Both pectins and fructans were related to antiglycation activity. Multiple species of Polygonatum are used as "Huangjing" in China and polysaccharides are the main effective constituents of "Huangjing". However, there is a lack of systematic comparison of polysaccharides from Polygonatum spp., and little work concerning on the polysaccharides from unofficial species. This paper conducted a comparison study on the characterization, high-performance gel permeation chromatography (HPGPC) saccharide mapping and antiglycation assay of polysaccharides and their enzymatic hydrolysates from nine species of Polygonatum. The results showed that polysaccharides from P. macropodium were mainly composed of fructans (3.3 × 103 Da); while polysaccharides from other eight Polygonatum spp. contained both fructans (2.5 × 103-4.1 × 103 Da) and pectins (more than 4.1 × 105 Da). Antiglycation assay showed that polysaccharides from Polygonatum spp. could significantly inhibit the formation of AGEs, and degradation of pectins and fructans could result in loss of activity. The results are helpful to the rational usage and quality control of Polygonatum spp. [ABSTRACT FROM AUTHOR]

• The thermal degradation has a greater impact on properties erosion of PMA. • For TDTTA or TFOT, the degradation of polymer is present base on analysis of GPC and FTIR. • The properties deterioration rate of PMA after TDTTA was not as serious as PMA after TFOT. • The performance erosion cannot be ignored when the air/oxygen is lack during the process of practical applications. Currently, more and more polymer modified asphalt binders (PMA) were used in road engineering in China. There are still many unqualified phenomena in the test of PMA samples on the construction site, which causes a confusion of suppler. To obtain the high quality of asphalt pavement, the effects of thermal degradation on PMA during storage and transportation become very important. This paper investigates physical properties and molecular structure of PMA samples by a series of test. The results of conventional tests indicated that time, temperature and oxygen concentration (thermal degradation test in thin air (TDTTA) and TFOT) have great effects on the deterioration of asphalt performance. For TDTTA or TFOT, the PMA exhibit performance erosion with time increasing. Moreover, the influences of temperature on physical properties of three PMA can be ranked as follows:163 °C＞150 °C＞130 °C. Compared with the effects of TDTTA on physical properties of three PMA, the TFOT has a more significant effect on physical properties of three PMA. The reason is that many scholars main focus on the study of conditions of high oxygen concentrated. Moreover, fourier transform infrared spectroscopy (FTIR) displayed that there were no chemical reaction found in three PMA. For TDTTA or TFOT, the degradation reaction of polymer in three PMA can clearly present base on analysis results of gel permeation chromatography (GPC) and FTIR. The performance erosion of PMA is more obvious in the air/oxygen compared with performance erosion of PMA in the thin air/oxygen, but the performance degradation cannot be ignored when the air/oxygen is lack during the process of practical applications. [ABSTRACT FROM AUTHOR]

• The thermal aging of high viscosity modified asphalt consists of three processes: polymer degradation, phase structure damage and asphalt oxidation. • In short-term aging, the degradation of polymer has a more pronounced effect on the property of high viscosity modified asphalt. • In long-term aging, the oxidation of asphalt is dominated for the property change of high viscosity modified asphalt. • High viscosity modified asphalt has a better aging resistance than PEN70 asphalt and SBS modified asphalt. Currently, the high viscosity modified asphalt (HVMA) is widely used in the porous asphalt pavement (PA) in China. HVMA provides good raveling resistance and rutting resistance for PA due to the excellent rheological property of it. However, the high construction temperature and the well-developed void structure of PA lead to a severe aging of HVMA. In order to understand the thermal aging behavior and mechanism of HVMA, the changes of rheological property, chemical composition, and phase morphology of HVMA, SBS modified asphalt (SBSMA) and PEN70 asphalt (70#A) during thermal aging process were investigated in this study. Rotational viscosity (RV) test, frequency sweep test, and multiple stress creep recovery (MSCR) test were used to evaluate the rheological property of HVMA. Then, Fourier transform infrared spectroscopy (FTIR) test and Gel permeation chromatography (GPC) test were used to determine the effect of thermal aging on the chemical composition of HVMA. Moreover, the phase morphology of HVMA, and SBSMA were observed by Fluorescence microscopic (FM) test. Test results indicate that the rotational viscosity, softening point, and strain recovery of HVMA show a decreasing trend initially and then increase with the process of thermal aging. The polymer phase structure of HVMA degrades obviously in short-term aging process, which leads to a deteriorated rheological property of HVMA. After long-term aging, the oxidation of base asphalt is the main reason for the changes in rheological property of HVMA. The aging resistance of HVMA is better than 70#A and SBSMA. As the amount of polymers increases, the aging resistance of HVMA is further improved. During thermal aging process, the polymer phase structure of HVMA is more abundant than SBSMA, which contributes to the superior anti-aging property of HVMA. [ABSTRACT FROM AUTHOR]

In the coastal areas of southeastern China, high temperatures and humidity in the summer and microfreezing in the winter, as well as a high concentration of salt spray in the environment, seriously deteriorate the durability of asphalt mixtures. Therefore, the microcharacteristics of asphalt mastics (asphalt mixed with mineral filler) under the effect of chlorine salt and "dry–wet and freeze–thaw" (DW-FT) cycles were investigated by Fourier-transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), and atomic force microscopy (AFM) techniques. Two factors, including asphalt mastic types (base and styrene-butadiene-styrene (SBS)-modified mastics) and numbers of DW-FT cycles, were considered based on the natural environment. Regression functions were established to explore the relationship between the FTIR, GPC, and AFM indexes. The results indicate that there were no chemical reactions between the asphalt and filler because the infrared spectrum of the base and SBS-modified mastics were similar. With the increase of the salt "DW-FT" cycle numbers, the sulfoxide index and large molecular size ratios ( L M S % ) increased, and the surface roughness ( R q and R a ) of the morphology decreased, as illustrated by a flatting mastics surface phenomenon in the AFM test. Regression analysis confirmed that there was a high correlation between the FTIR, GPC, and AFM indexes, and formation of the bee structures was closely related to the long chain index. The SBS-modified mastics had a better antiaging performance with a lower increase in the sulfoxide index after the salt "DW-FT" cycles in the coastal environment. [ABSTRACT FROM AUTHOR]