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The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a serious threat to global public health. In an effort to develop novel anti-coronavirus therapeutics and achieve prophylactics, we used gene set enrichment analysis (GSEA) for drug screening and identified that Astragalus polysaccharide (PG2), a mixture of polysaccharides purified from Astragalus membranaceus , could effectively reverse COVID-19 signature genes. Further biological assays revealed that PG2 could prevent the fusion of BHK21-expressing wild-type (WT) viral spike (S) protein and Calu-3-expressing ACE2. Additionally, it specifically prevents the binding of recombinant viral S of WT, alpha, and beta strains to ACE2 receptor in our non-cell-based system. In addition, PG2 enhances let-7a , miR-146a , and miR-148b expression levels in the lung epithelial cells. These findings speculate that PG2 has the potential to reduce viral replication in lung and cytokine storm via these PG2-induced miRNAs. Furthermore, macrophage activation is one of the primary issues leading to the complicated condition of COVID-19 patients, and our results revealed that PG2 could regulate the activation of macrophages by promoting the polarization of THP-1-derived macrophages into an anti-inflammatory phenotype. In this study, PG2 stimulated M2 macrophage activation and increased the expression levels of anti-inflammatory cytokines IL-10 and IL-1RN. Additionally, PG2 was recently used to treat patients with severe COVID-19 symptoms by reducing the neutrophil-to-lymphocyte ratio (NLR). Therefore, our data suggest that PG2, a repurposed drug, possesses the potential to prevent WT SARS-CoV-2 S-mediated syncytia formation with the host cells; it also inhibits the binding of S proteins of WT, alpha, and beta strains to the recombinant ACE2 and halts severe COVID-19 development by regulating the polarization of macrophages to M2 cells.

The objective of this work was characterize and evaluate the protein-stabilizing property of pea soluble polysaccharide (PSPS) extracted from pea by-products using spray-drying and ethanol precipitation oven drying, obtaining PSPS-A and PSPS-B, respectively. The weight average molecular weight (Mw) of PSPS-A and PSPS-B were 625 kDa and 809 kDa, respectively. The results of Fourier transform infrared spectroscopy (FT-IR) analysis indicated that PSPS-A, PSPS-B and soybean soluble polysaccharide (SSPS) contained the same functional groups. The absolute negative charges of PSPS-A or PSPS-B in aqueous solution were slightly higher than that of SSPS at pH 2.0 to 7.0. The apparent diameter of PSPS-B (479.1 nm) was larger than that of PSPS-A (127.7 nm) and SSPS (209.5 nm) were measured by dynamic light scattering. The AFM images revealed that both PSPS-A and PSPS-B possessed star-like structures with more side chains as compared to SSPS. It was found that the addition of 0.15% PSPS-A or 0.1% PSPS-B was adequate to prevent the aggregation of protein and obtain stable dispersion. Furthermore, PSPS has a wider pH range (pH 3.6-4.6) to stabilize milk protein than SSPS (pH 3.6-4.2)., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Rosa laevigata fruit has been known as a functional foodstuff for a long time. Recently, increasing attention has been given to polysaccharides from R. laevigata fruit due to their numerous medicinal and nutritional properties. In this study, a rapid and effective approach for the extraction and separation of polysaccharides from the title fruit was developed using microwave-assisted aqueous two-phase extraction (MA-ATPE) with a PEG/ammonium sulfate system. After analysis of the response surface methodology (RSM) data based on a Box-Behnken design (BBD), a model was proposed and was found to predict an optimum yield value of 258.99 mg g -1 which is in good agreement with the experimental value (258.59 mg g -1 ). Two selenium (Se)-containing polysaccharides, Se-RLFP-1 and Se-RLFP-2, were isolated from R. laevigata fruit. Their chemical structures were elucidated by acid hydrolysis, weight-average molecular mass and Se-content analysis, along with UV, FT-IR, 1 H and 13 C NMR spectroscopy. As a result, Se-RLFP-1 was found to be mainly composed of mannose, glucose, galactose and xylose in a molar ratio of 1.4 : 7.9 : 1.0 : 1.5, while Se-RLFP-2 was composed of mannose, rhamnose, glucose, galactose and xylose (12.6 : 1.0 : 38.3 : 5.6 : 19.6). Furthermore, the antioxidant properties of the polysaccharides were investigated on the basis of FRAP, ABTS and DPPH radical scavenging assays. The results showed that the two polysaccharides had a noticeable effect on the radical scavenging of ABTS and DPPH, especially at high concentrations. In addition, the neuroprotective effect of Se-RLFP-1 and Se-RLFP-2 against oxidative stress induced by H 2 O 2 in SH-SY5Y neuroblastoma cells was also investigated. In particular, Se-RLFP-1 exhibited obvious neuroprotective activity at a concentration of 100 μg mL -1 .

Acutobin isolated from Deinagkistrodon acutus venom has been used to prevent or treat stroke in patients. This defibrinogenating serine protease is a 39 kDa glycoprotein containing terminal disialyl-capped N-glycans. After sialidase treatment, the enzyme showed similar catalytic activities toward chromogenic substrate, and cleaved the Aα chain of fibrinogen as efficiently as the native acutobin did. However, the level of fibrinogen degradation products in mice after i.p.-injection of desialylated-acutobin was significantly lower than the level after acutobin injection, suggesting that the disialyl moieties may improve or prolong the half-life of acutobin. Two recombinant enzymes with identical protein structures and similar amidolytic activities to those of native acutobin were expressed from HEK293T and SW1353 cells and designated as HKATB and SWATB, respectively. Mass spectrometric profiling showed that their glycans differed from those of acutobin. In contrast to acutobin, HKATB cleaved not only the Aα chain but also the Bβ and γ chains of human fibrinogens, while SWATB showed a reduced α-fibrinogenase activity. Non-denaturing deglycosylation of these proteases by peptide N-glycosidase F significantly reduced their fibrinogenolytic activities and thermal stabilities. The in vivo defibrinogenating effect of HKATB was inferior to that of acutobin in mice. Taken together, our results suggest that the conjugated glycans of acutobin are involved in its interaction with fibrinogen, and that the selection of cells optimally expressing efficient glycoforms and further glycosylation engineering are desirable before a recombinant product can replace the native enzyme for clinical use.

Glycosylation analysis of nonmammalian sources often springs surprises and conjures up intriguing views of evolutionary adaptation. Many of the constituents of snake venoms are known to be glycosylated and yet very few were fully characterized and accorded specific functions. In the process of glycomic screening through the venoms from Asian pit vipers, a partially O-acetylated NeuAcα2-8NeuAcα2-3Galβ1-4GlcNAcβ1-terminal epitope was found to be the predominant glycosylation characteristic of the snake venom produced by the monotypic Deinagkistrodon acutus, with acutobin, a highly specific fibrinogenase, being identified as a primary protein carrier. Full structural definition and glycosylation site mapping were completed through advanced mass spectrometry analyses at both the glycan and glycopeptide levels in conjunction with chemical and enzymatic cleavages. Although similar occurrence of such terminal disialyl cap on the N-glycans of several mammalian glycoproteins has been implicated, most of these correspond to only minor constituents of the full glycomic heterogeneity and remain poorly characterized. In contrast, each antennae of the hybrid- and complex-type N-glycans derived from acutobin was found to be rather homogeneously disialylated. With up to eight sialic acids evenly distributed on nonextended tetraantennary core structure, these unusual N-glycans are among those of highest sialic acid density ever identified without actually carrying polysialic acid chains. It remains to be tested whether they may serve as multivalent disialyl ligands for several of the human Siglecs and thus meddle with the natural immuno-recognition systems of snakebite victims, apart from affecting the general efficacy of acutobin as anticoagulant in biomedical applications.

The coagulation factor X activator from Russell's viper venom (RVV-X) is a heterotrimeric glycoprotein. In this study, its three subunits were cloned and sequenced from the venom gland cDNAs of Daboia siamensis. The deduced heavy chain sequence contained a C-terminal extension with four additional residues to that published previously. Both light chains showed 77-81% identity to those of a homologous factor X activator from Vipera lebetina venom. Far-western analyses revealed that RVV-X could strongly bind protein S, in addition to factors X and IX. This might inactivate protein S and potentiate the disseminated intravascular coagulation syndrome elicited by Russell's viper envenomation. The N-glycans released from each subunit were profiled and sequenced by MALDI-MS and MS/MS analyses of the permethyl derivatives. All the glycans, one on each light chain and four on the heavy chain, showed a heterogeneous pattern, with a combination of variable terminal fucosylation and sialylation on multiantennary complex-type sugars. Amongst the notable features were the presence of terminal Lewis and sialyl-Lewis epitopes, as confirmed by western blotting analyses. As these glyco-epitopes have specific receptors in the vascular system, they possibly contribute to the rapid homing of RVV-X to the vascular system, as supported by the observation that slower and fewer fibrinogen degradation products are released by desialylated RVV-X than by native RVV-X.

Lessertia frutescens is a perennial shrub of commercial importance in South Africa, but the scarcity of plant resources has limited current product production. In this study, to provide an alternative approach for obtaining L. frutescens material, adventitious roots (ARs) were induced from sterilized seedlings and cultured in a suspension culture system. During this process, selection tests were conducted to find a suitable auxin and its concentration for AR induction and a suitable basal medium for AR growth and metabolite accumulation; a kinetic study was then performed to constructure kinetic models. The results showed that compared to other auxins and concentrations, indole-3-butyric acid at 3 mg/L was suitable for increasing the number and length of ARs during AR induction. In AR suspension culture, Schenk and Hildebrandt (SH) was better than other basal media, and the maximum AR fresh (86.9 g/L) or dry weight (5.5 g/L), total triterpenoid saponin (92.6 mg/g DW), and polysaccharide (114.7 mg/g DW) contents were determined in the 1.5×SH medium. In addition, AR biomass and metabolite contents reached the maximum on day 42. The kinetic models for AR growth and triterpenoid and polysaccharide production were constructed, providing the basis for further optimization of culture conditions and large-scale culture. • Auxin type and concentration affected AR induction and 3 mg/L IBA was most suitable. • The 1.5×SH basal medium was advantageous for AR suspension culture. • The most suitable time for harvesting ARs was 42 days of suspension culture. • The kinetic models of AR growth and metabolite production were successfully constructed. [ABSTRACT FROM AUTHOR]

Aging is characterized by inevitable organ function decline over time, with consequent body deterioration and increased susceptibility to death. Astragalus polysaccharide (APS) has been reported to have anti‐oxidative, anti‐apoptotic, and anti‐inflammatory properties. We investigated the potential protective effects of APS on hydrogen peroxide (H2O2) induced hepatocyte senescence and identified related mechanisms in L02, Huh7, and LM3 cell lines. Aged female C57BL/6 mice were given APS for 1 week by intraperitoneal injection, and APS provided the strongest protective effect against H2O2‐induced damage at 100 μM. APS reduced the expression of cell senescence markers and alleviated pathological damage in aged mouse liver. APS treatment decreased oxidative stress, apoptosis, NOD‐like receptor protein‐3‐mediated pyroptosis, and maintained mitochondrial homeostasis. Notably, the protective effect of APS was weakened in the presence of chloroquine. APS might enrich autophagy by activating AMP‐activated protein kinase (AMPK) and inhibiting mammalian target of rapamycin (mTOR). In conclusion, APS reduced reactive oxygen species levels, inhibited apoptosis and pyroptosis, and promoted mitophagy via AMPK/mTOR pathway to alleviate hepatocyte senescence in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The present study designed two sets of experiments by using the uniform design method and investigated the effects of medium components on the accumulation of bioactive compounds (polysaccharide and kinsenoside) in rhizomes, in order to select a suitable culture medium for the rhizome suspension culture of Anoectochilus roxburghii (Wall.) Lindl. Among the combinations of Murashige and Skoog (MS) medium strengths and plant growth regulator (benzylaminopurine, BA; kinetin, KT; and α-naphthaleneacetic acid, NAA) concentrations, and the combinations of nitrogen, phosphorus, and sucrose concentrations, the maximum yield of polysaccharides and kinsenoside was achieved with 0.75 × MS + 2.0 mg L−1 BA + 0.2 mg L−1 KT + 0.5 mg L−1 NAA and 45 mM nitrogen + 0.93 mM phosphorus + 35 g L−1 sucrose, respectively. Therefore, the optimal rhizome suspension culture medium was 0.75 × MS medium supplemented with 2.0 mg L−1 BA, 0.2 mg L−1 KT, 0.5 mg L−1 NAA, and 35 g L−1 sucrose. Yeast extract (YE) enhanced bioactive compound accumulation in rhizomes. The polysaccharide and kinsenoside production was significantly improved when 75 mg L−1 YE was added to the culture medium after 30 d of rhizome suspension culture; 8.3 g L−1 of polysaccharide and 6.1 g L−1 of kinsenoside were obtained after 4 d of YE treatment. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of YE-treated rhizomes was higher than that of YE-untreated rhizomes, demonstrating enhanced antioxidant activity of the treated bioreactor-cultured rhizomes. [ABSTRACT FROM AUTHOR]

Fed-batch culture is rarely applied in plant organ culture, but it has been attempted to be used in Oplopanax elatus adventitious root (AR) culture. To establish a complete fed-batch O. elatus AR culture system, this study investigated the effects of sucrose, phosphorus, and nitrogen concentrations in the initial medium, and feeding time, feeding volume, and harvest time on AR biomass and flavonoid or polysaccharide accumulation. The results indicated the initial medium (3 L) containing 0.938 mM phosphorus and 40 mM nitrogen supplemented with 40 g/L sucrose, feeding with 2 L feeding medium on the 15th day, and harvesting on the 45th day were the most suitable conditions for the production of flavonoid- and polysaccharide-enriched ARs. In the established culture system, 76.7 mg/L/day of flavonoids and 200.9 mg/L/day of polysaccharides were obtained. This study suggested that fed-batch culture is a promising approach for mass production of O. elatus ARs. [Display omitted] • Fed-batch culture system of Oplopanax elatus adventitious roots is established. • Sucrose, phosphorus, and nitrogen concentrations in initial medium are optimized. • Suitable feeding time and feeding volume are selected. • Harvesting adventitious roots after 40 days of culture is the most optimal. • Fed-batch cultured adventitious roots contain rich flavonoids and polysaccharides. [ABSTRACT FROM AUTHOR]

GC-MS method combined with FTIR techniques by the analysis of polysaccharide was applied to evaluate the similarity between wild (W) and tissue-cultured (TC) Dendrobium huoshanense (DHS), Dendrobium officinale (DO), and Dendrobium moniliforme (DM) as well as 3 wild Dendrobium spp.: Dendrobium henanense (DHN), Dendrobium loddigesii (DL), and Dendrobium crepidatum (DC). Eight monosaccharides involving xylose, arabinose, rhamnose, glucose, mannose, fructose, galactose, and galacturonic acid were identified in the polysaccharide from each Dendrobium sample while the contents of the monosugars varied remarkably across origins and species. Further similarity evaluation based on GC-MS data showed that the rcor values of different origins of DHS, DO, and DM were 0.831, 0.865, and 0.884, respectively, while the rcor values ranged from 0.475 to 0.837 across species. FTIR files of the polysaccharides revealed that the similarity coefficients between W and TC-DHS, DO, and DM were 88.7%, 86.8%, and 88.5%, respectively, in contrast to the similarity coefficients varying from 57.4% to 82.6% across species. These results suggested that the structures of polysaccharides between different origins of the investigated Dendrobiums might be higher than what we had supposed. [ABSTRACT FROM AUTHOR]

The article presents a scientific research on the isolation and characterization of a pure mannan from Oncidium Gower Ramsey, a sympodial orchid, current pseudobulb during the early inflorescence stage. The experiment resulted to the discovery of a water-soluble and neutral polysachharide that was extracted from current pseudobulbs of Oncidium Gower Ramsey during initial inflorescence development. The polysaccharide was identified as a linear β‐ 1 → 4 linked mannan.

Fed-batch culture of plant cells can enhance biomass and bioactive compound accumulation compared with batch culture, in which the initial culture medium is one of the controllable factors in the fed-batch culture system. Rhodiola sachalinensis is a valuable medicinal herb and its cell culture is an alternative approach to obtaining plant material. R. sachalinensis cells has been previously cultured in a fed-batch culture system and the initial culture medium has been found to critically affect production yield. Therefore, this study investigated the effect of nitrogen concentration, ammonia and nitrate ratio (NH 4 +/NO 3 -), and phosphorus and calcium concentrations in initial culture medium on cell biomass, as well as salidroside and polysaccharide accumulation to improve the fed-batch culture efficiency. Then, the cultured cells were extracted by flash extraction and the extraction conditions were optimized by Box-Behnken Design Response Surface Method (BBD–RSM). Finally, the antibacterial and antibiofilm effects of the extract were examined to further utilize R. sachalinensis cell cultures. The results showed that the fed-batch culture efficiency was obviously improved when the initial culture medium was modified as 30 mM of nitrogen with 5/25 of NH 4 +/NO 3 -, 0.94 mM of phosphorus, and 2.3 mM of calcium, at which 277.3 mg/L of salidroside and 4.5 g/L of polysaccharides were obtained In flash extraction, polysaccharide yield was as the response value to optimize extraction process by controlling extraction time, extraction temperature, and liquid–solid ratio in the BBD–RSM experiments. The optimal flash extraction conditions were 55.7 s of extraction time, 56.5 °C of extraction temperature, and 37.0 mL/g of liquid–solid ratio, which the polysaccharide yield reached 12.76% under the optimized conditions. In antibacterial experiment, the cell extract (RCE) inhibited the growth of Bacillus subtilis, Pseudomonas aeruginosa , and Salmonella choleraesuis ; the biofilm of B. subtilis and S. choleraesuis was scavenged in the groups of 8 mg/mL and 16 mg/mL RCE. The findings provided a basis for further industrial production of cell cultures and a theoretical reference in using R. sachalinensis cells in the production of antibacterial-related products. [Display omitted] • Salt concentrations in initial culture medium strongly affected fed-batch culture efficiency of Rhodiola sachalinensis cells. • The suitable concentrations of nitrogen, phosphorous, and calcium were confirmed. • Extract from cultured cells can be efficiently extracted in a flash extractor. • Extraction process was optimized by adjusting extraction time, temperature, and liquid−solid ratio. • The cultured cells possessed anti-bacterial and antibiofilm activities. [ABSTRACT FROM AUTHOR]

Highlights • Rhizome cultures is an alternative plant material of Anoectochilus roxburghii (Wall.) Lindl. • Bioactive compound synthesis of rhizomes was obviously improved after elicitation. • Elicitation effect of salicylic acid was better than that of methl jasmonate. • Treatment of 500 μM salicylic acid for 12 days is the most optimal. Abstract Elicitation is an efficient strategy for enhancement of metabolite production during plant cell or organ culture. Salicylic acid (SA) and methyl jasmonate (MeJA) are the wildly used abiotic elicitors. To improve the accumulation of the kinsenoside and polysaccharides in rhizome cultures of Anoectochilus roxburghii (Wall.) Lindl., the present study added SA or MeJA to the culture medium after 30 days of rhizome suspension culture, and the effects of concentration and elicitation time of both elicitors on the kinsensode and polysaccharide accumulation were investigated. SA and MeJA efficiently enhanced contents of the bioactive compounds in concentration- and time-dependent manners. In SA groups, the maximum kinsenoside and polysaccharide contents were determined when rhizomes were treated with 500 μM SA for 12 days; in MeJA groups, kinsenoside and polysaccharide contents reached the highest levels when rhizomes were treated with 550 μM MeJA for 14 days and 16 days, respectively. In addition, the elicitation effects were compared in a large-scale bioreactor system. Kinsenoside and polysaccharide contents were markedly improved by elicitation with SA and MeJA compared with the un-elicited rhizomes and field-grown plants. The SA-treated group produced high kinsenoside (661.4 mg/g DW), which was 1.9-fold more than that from MeJA treatment. No significant difference was found in the polysaccharide content between SA and MeJA treatments. Thus, SA is a promising elicitor to economically improve the industrial production of kinsenoside and polysaccharides during rhizome culture of A. roxburghii. [ABSTRACT FROM AUTHOR]

Malignant melanoma is an invasive and highly aggressive skin cancer that—if diagnosed—poses a serious threat to the patient's health and life. In this work, a novel purified cell-wall polysaccharide (termed Abwp) was obtained from the discarded stipe of Agaricus bisporus (A. bisporus) and characterized to be a novel homogeneous polysaccharide consisted of a β-(1 → 4)- glucosyl backbone with β-(1 → 2) and (1 → 6)- d -glucosyl side-chains. The anti-melanoma effects of Abwp and its associated mechanisms in mice were then explored using in vitro and in vivo approaches. In vitro results showed that Abwp inhibited B16 melanoma cell proliferation and promoted their apoptosis in both time- and dose-dependent manners. In B16 cells induced with tumor necrosis factor (TNF-α), Abwp significantly decreased the protein expression of inflammatory-related signaling pathway (e.g., p38 MAPK and NF-κB) in time-, concentration-, and dose-dependent manners. Moreover, Abwp blocked nuclear entry of NF-κB-p65. In an in vivo mouse model featuring neoplasm transplantation with B16 melanoma cells, Abwp significantly inhibited the growth and proliferation of mouse melanoma. Hematoxylin staining showed that the invasion of melanoma cells into the lung tissue of the Abwp-treated group was significantly reduced. Immunohistochemical analysis showed that the expression of proliferation cell nuclear antigen (PCNA), N-cadherin, MMP-9, and Snail in the lung of mouse was significantly inhibited. Immunofluorescence showed that Abwp significantly interfered with the nuclear transcription of NF-κB-p65 in a dose-dependent manner. Collectively, these results showed that Abwp mediated p38 MAPK and NF-κB signaling pathways to inhibit the inflammatory response and malignant proliferation and metastasis of melanoma in mice. [Display omitted] • A homogeneous β-glucan was obtained and characterized from Agaricus bisporus cell-wall. • The anti-melanoma effects were explored using in vitro and in vivo approaches. • The β-glucan inhibits mouse melanoma proliferation and metastasis by p38 MAPK and NF-κB signaling pathways. [ABSTRACT FROM AUTHOR]

Soybean soluble polysaccharide (SSPS) is anionic polysaccharide extracted from the by-product of isolated soy protein production. In this study, a simple and eco-friendly procedure had been developed to prepare high-molecular-weight octenyl succinic esters of SSPS (OSA-SSPS) via the esterification between SSPS and octenyl succinic anhydride (OSA). The absolute molecular weights of OSA-SSPS and SSPS were 620 kDa and 53 kDa, respectively. OSA-SSPS had some similar properties to SSPS, such as microstructure and viscosity of 1 wt% concentration. However, compared to SSPS, OSA-SSPS showed different milk protein stabilization properties. The stabilizing behavior of OSA-SSPS was better than that of SSPS at pH range of 3.8–4.6, and poorer at pH 3.6. The model mixture of OSA-SSPS had smaller particle sizes at pH range of 3.8–4.6 and larger absolute negative charges at pH 2.0–10.0. In addition, from the molecular diameter measured by DLS and AFM image, the surface concentration of OSA-SSPS was larger than that of SSPS, which indicated that the thicker OSA-SSPS layer produces larger steric repulsion to milk protein particles. The mechanism for the greater ability of OSA-SSPS to stabilize milk proteins was proposed on the basis of the results discussed in this research. [ABSTRACT FROM AUTHOR]

This research presents a green procedure to prepare oil in water (O/W) emulsion from acid soluble soy protein (ASSP) and soy soluble polysaccharide (SSPS), a long-term stable nanoscale system for delivering the lipophilic components. The emulsion technique involved the preparation complexion using ASSP and SSPS by electrostatic and hydrophobic interactions as well as high pressure homogenization. The average diameter of the droplet of emulsions (fresh and heated) is 263 ± 2 nm. Such emulsions resulted in heating stable dispersions containing corn oil at the concentration of 20.0%, even at the pH around the isoelectric points of ASSP. After 90 days storage at 4 °C, the mean diameter of emulsions after heating at 80 °C for 60 min is 314 ± 1 nm compared with 341 ± 3 nm of emulsions unheated. The heat-stability of dispersions were affected by emulsion conditions, so the present research demonstrates the emulsion stability against heat treatment, ionic strength and pH change. [ABSTRACT FROM AUTHOR]

Abstract: The conjugation reaction between soy β-conglycinin and dextran via Maillard reaction in crowded liquid system was studied. Apparent viscosity indicated that environment became more and more crowded with the increase of dextran concentration. The covalently linked conjugate was produced by incubating aqueous solution containing soy β-conglycinin and dextran at pH7.0 and 95°C for 6h. Free amino group content and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profile showed that soy β-conglycinin–dextran conjugate was successfully formed and macromolecular crowding enhanced the extent of glycation. The results of atomic force microscopy indicated that glycation inhibited the thermal aggregate of protein. Meanwhile, the tertiary structure of protein in conjugate changed with increasing number of aromatic side-chains exposed in heating environment. All data showed that the introduction of macromolecular crowding in soy β-conglycinin–dextran conjugate was an effective and promising method for linking polysaccharides to proteins. [Copyright &y& Elsevier]

Two sequencing batch reactors (SBRs) were concurrently operated to investigate the effect of Mg2+ augmentation on aerobic granulation. Augmentation with 10mg/l Mg2+ in R2 significantly decreased the sludge granulation (defined as that over 15% of granules were larger than 0.6mm) time from 32days to 18days, at the same time, the mean diameter of the granules in R2 was 2.9mm after the granulation, which was consistently larger than that (1.8mm) in R1. Mg2+-fed granules were denser and more compact, showed better settling and had higher polysaccharide contents, but it did not result in a difference in microbial morphology. The results demonstrated that Mg2+ enhanced the sludge granulation process in the sequencing batch reactor. [Copyright &y& Elsevier]