Publications by authors named "Peixin He"

30 Publications

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The thermal/pH-sensitive drug delivery system encapsulated by PAA based on hollow hybrid nanospheres with two silicon source.

J Biomater Sci Polym Ed 2020 Dec 28:1-19. Epub 2020 Dec 28.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan, China.

The synthesis of drug delivery systems based on hollow mesoporous silica nanoparticles (MSNs) is still a major challenge. In this work, the hollow hybrid MSNs were successfully prepared by cetyltrimethylammonium bromide-directed sol-gel process and one-step hydrothermal treatment process. The hollow hybrid MSNs had hybrid ethane-bridged frameworks with the uniform particle size (250 nm) and mesoporous pore diameter (3.7 nm). The polyacrylic acid (PAA) encapsulated drug delivery system based on hollow hybrid MSNs was prepared by using silanization, surface modification, doxorubicin hydrochloride (DOX) loading, and PAA coating. Drug encapsulation and release behavior at different temperatures and pH were studied by using DOX as a model guest molecule. The results displayed that the modified hollow ethane-bridged MSNs possessed good biocompatibility and excellent thermal/pH-dual-sensitive drug release property. This novel thermal/pH-sensitive drug delivery system based on hollow ethane-bridged MSNs has the advantages of feasible synthesis, no cytotoxicity, and good drug loading capacity, which may have potential applications in the anticancer therapy.
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http://dx.doi.org/10.1080/09205063.2020.1861734DOI Listing
December 2020

Discovery and identification of medium-chain fatty acid responsive promoters in .

Eng Life Sci 2020 Apr 21;20(5-6):186-196. Epub 2020 Jan 21.

CAS Key Laboratory of Systems Microbial Biotechnology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences (CAS) Tianjin P. R. China.

Medium-chain fatty acids (MCFAs) and their derivatives are important chemicals that can be used in lubricants, detergents, and cosmetics. MCFAs can be produced in several microbes, although production is not high. Dynamic regulation by synthetic biology is a good method of improving production of chemicals that avoids toxic intermediates, but chemical-responsive promoters are required. Several MCFA sensors or promoters have been reported in . In this study, by using transcriptomic analysis of exposed to fatty acids with 6-, 12-, and 16-carbon chains, we identified 58 candidate genes that may be responsive to MCFAs. Using a fluorescence-based screening method, we identified MCFA-responsive promoters, four that upregulated gene expression, and three that downregulated gene expression. Dose-response analysis revealed that some of the promoters were sensitive to fatty acid concentrations as low as 0.02-0.06 mM. The MCFA-responsive promoters reported in this study could be used in dynamic regulation of fatty acids and fatty acid-derived products in .
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http://dx.doi.org/10.1002/elsc.201900093DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7447867PMC
April 2020

Interspecific hybridization between cultivated morels Morchella importuna and Morchella sextelata by PEG-induced double inactivated protoplast fusion.

World J Microbiol Biotechnol 2020 Mar 31;36(4):58. Epub 2020 Mar 31.

Institute of Applied Mycology, Huazhong Agricultural University, Wuhan, 430070, China.

The commercial production of Morchella mushrooms calls for urgent breeding of excellent varieties or strains with appropriate tools, such as protoplast fusion. However, the protoplast fusion in morels has not been studied. In this paper, interspecific hybridization between cultivated morels of M. importuna and M. sextelata by PEG-induced protoplast fusion was conducted. Apart from functional complementation of double inactivated protoplasts, the fusants were characterized by cultural and cultivated characters and molecular markers of random amplified polymorphic DNA (RAPD). The results suggested that the hybrids and their parents showed significant difference in their inoculum recovery time, mycelial growth rate, yield of cultivation and total amino acid content of ascocarps. Moreover, positive barrage reactions were observed between parental strains as well as between each parent and a hybrid line. A dendrogram created on the basis of RAPD fingerprints exhibited three major clusters, in which morel hybrids showed intra-cluster variations, M. sextelata #6 formed an out group, while M. importuna #4 was phylogenetically closer to morel hybrids. All the results demonstrated that real fusants were obtained in our study. Protoplast fusion may provide an ideal alternative for new strain selection, and thus will promote the healthy development of morel industry.
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http://dx.doi.org/10.1007/s11274-020-02835-0DOI Listing
March 2020

Co-occurrence patterns among prokaryotes across an age gradient in pit mud of Chinese strong-flavor liquor.

Can J Microbiol 2020 Sep 1;66(9):495-504. Epub 2020 Apr 1.

School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, Henan Province, People's Republic of China.

It is widely believed that the quality and characteristics of Chinese strong-flavor liquor (CSFL) are closely related to the age of the pit mud; CSFL produced from older pit mud tastes better. This study aimed to investigate the alteration and interaction of prokaryotic communities across an age gradient in pit mud. Prokaryotic microbes in different-aged pit mud (1, 6, and 10 years old) were analyzed by Illumina MiSeq sequencing of the 16S rRNA gene. Analysis of the 16S rRNA gene indicated that the prokaryotic community was significantly altered with pit mud age. There was a significant increase in the genera , , and with increased age of pit mud, while the genus showed a significant decreasing trend. Network analysis demonstrated that both synergetic co-occurrence and niche competition were dominated by 68 prokaryotic genera. These genera formed 10 hubs of co-occurrence patterns, mainly under the phyla , , and , playing important roles on ecosystem stability of the pit mud. Environmental variables (pH, NH, available P, available K, and Ca) correlated significantly with prokaryotic community assembly. The interaction of prokaryotic communities in the pit mud ecosystem and the relationship among prokaryotic communities and environmental factors contribute to the higher quality of the pit mud in older fermentation pits.
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http://dx.doi.org/10.1139/cjm-2020-0012DOI Listing
September 2020

Tumor-mediated shape-transformable nanogels with pH/redox/enzymatic-sensitivity for anticancer therapy.

J Mater Chem B 2020 05;8(17):3801-3813

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules of Ministry of Education, Key Laboratory for the Green Preparation and Application of Functional Materials of Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China. and The State Key Laboratory of Bioreactor Engineering and Key Laboratory for Ultrafine Materials of Ministry of Education, Key Laboratory for Ultrafine Materials of Ministry of Education, Engineering Research Centre for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China.

Lack of sufficient tumor penetration of the current nanomedicines is a major reason limiting their clinical success in cancer therapy. In this work, we aimed at the development of a novel biodegradable nanoplatform for the selective and controlled delivery of anticancer agents, with improved tumor permeability and the ability to release ultrasmall nanovesicles in the tumor microenvironment. To this end, positively charged nanogels were obtained through the double-crosslinking of chitosan with an ionic physical gelator and a disulfide-containing chemical crosslinker. After conjugation to an anionic oligomer, the cationic nanogels were transformed into negatively charged nanocarriers (CTCP), enabling effective encapsulation of the cationic anticancer agent doxorubicin (DOX) to generate a biodegradable nanomedicine (DOX@CTCP). DOX@CTCP could maintain sustained DOX release and decreased DOX toxicity. Upon arrival at the tumor tissue, the reductive and lysozyme-high microenvironment drives the cleavage of the nanomedicine to release DOX-carrying nanoblocks of smaller size, which together with their acidic-protonable feature achieves an effective therapeutic delivery into cancer cells. The nanomedicine described here showed excellent biocompatibility/biosafety and enhanced in vivo antitumor efficacy.
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http://dx.doi.org/10.1039/d0tb00143kDOI Listing
May 2020

Optimizing the DO-stat protocol for enhanced production of thermostable pullulanase in Escherichia coli by using oxygen control strategies.

J Food Biochem 2020 05 9;44(5):e13173. Epub 2020 Mar 9.

School of Food and Bioengineering, Zhengzhou University of Light Industry, Zhengzhou, China.

Production of a thermostable pullulanase by DO-stat fed-batch fermentation of recombinant Escherichia coli BL 21 was investigated in a 5 L of fermentor. The effect of three oxygen control strategies, glucose feedback, shifting fermentor pressure, and adding oxygen-enriched air, on cell growth and pullulanase expression were examined. The oxygen-transfer capacity was found to be enhanced with increasing fermentor pressure and oxygen ratio in oxygen-enriched air, but the cell growth and pullulanase production were restrained under high fermentor pressure. The highest cell density and pullulanase activity reached 55.1 g/L and 412 U/mL, respectively, in the case by adding oxygen-enriched air, which was suggested as an effective approach to enhance both cell growth and pullulanase production. PRACTICAL APPLICATIONS: This thermostable pullulanase displayed optimal activity at 90°C and pH 5.4, which could be applied for one-step saccharification of starch biomass. The optimization of the DO-stat fed-batch fermentation in high cell density level would provide a research basis for its industrialization.
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http://dx.doi.org/10.1111/jfbc.13173DOI Listing
May 2020

Characterization and Antioxidant Activity of a Low-Molecular-Weight Xanthan Gum.

Biomolecules 2019 11 12;9(11). Epub 2019 Nov 12.

College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China.

In the present work, a low-molecular-weight xanthan gum (LW-XG) was successfully obtained via biodegradation of commercial xanthan by the endophytic fungus CGMCC 6882. The monosaccharide composition of LW-XG was glucose, mannose, and glucuronic acid in a molar ratio of 1.63:1.5:1.0. The molecular weight of LW-XG was 4.07 × 10 Da and much smaller than that of commercial xanthan (2.95 × 10 Da). Antioxidant assays showed that LW-XG had a good scavenging ability on DPPH radicals, superoxide anions, and hydroxyl radicals and good ferric reducing power. Moreover, LW-XG exhibited excellent protective effect on HO-injured Caco-2 cells. Results of this work suggested that LW-XG could be used in foods or pharmaceuticals to alleviate and resist the oxidative damage induced by the overproduction of reactive oxygen species.
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http://dx.doi.org/10.3390/biom9110730DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6920750PMC
November 2019

Hybrid mesoporous silica nanospheres modified by poly (NIPAM-co-AA) for drug delivery.

Nanotechnology 2019 Aug 9;30(35):355604. Epub 2019 May 9.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, People's Republic of China.

The synthesis of drug delivery systems based on surface-modified mesoporous silica hollow structures remains a huge challenge. In this paper, we have obtained hollow mesoporous silica nanoparticles (MSNs) by surfactant directed sol-gel assisted hydrothermal treatment. The MSNs have the inorganic-organic hybrid frameworks with uniform diameter distribution (260 nm), and their specific surface area, mesoporous size and pore volume are 540 m g, 3.7 nm, 0.58 cm g, respectively. It was proved that the preparation of hollow ethane-bridged nanospheres with two silicon source was due to the high crosslinking of the silicone interface and hydrothermal treatment, providing a new approach for the study of drug-loaded and controlled release behavior. Based on the synthesis of MSNs, MSNs were modified by methacryloxy propyl trimethoxyl silane (MPS) on the surface of MSNs. Then N-isopropylacryamide (NIPAM) and acrylic acid (AA) were grafted onto the surface of modified MSNs. The hollow ethane-bridged PNA-MSNs (poly (NIPAM-co-acrylic acid)-MSNs) with two silicon source were prepared successfully. Due to their distinctive hollow structure, PNA-MSNs demonstrated high drug encapsulation efficiency (70.4% ± 2.9%). The experiment results proved that the modified hollow nanoparticles not only had good biocompatibility and stability, but also possessed pH-/thermal-dual responsiveness in drug release.
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http://dx.doi.org/10.1088/1361-6528/ab209dDOI Listing
August 2019

Formation of enzymatic/redox-switching nanogates on mesoporous silica nanoparticles for anticancer drug delivery.

Mater Sci Eng C Mater Biol Appl 2019 Jul 9;100:855-861. Epub 2019 Mar 9.

The Key Laboratory for Ultrafine Materials of Ministry of Education, State Key Laboratory of Bioreactor Engineering and Engineering Research Centre for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China. Electronic address:

In this study, we demonstrate a simple approach to developing mesoporous nanohybrids via a process of pre-loading of an anticancer drug (doxorubicin, DOX) into mesoporous silica nanoparticles (MSN), followed by assembly with a kind of naturally-derived polymer (gelatin, cleavable by matrix metalloproteinase 2 overexpressed by tumor). The gelatin shell is then in situ crosslinked by degradable N,N'-bis(acryloyl)cystamine (BAC) to form enzymatic and redox switchable nanogates on the mesoporous nanoparticles. The nanohybrids displayed pH/redox/enzymatic sensitivity in DOX release under conditions mimicking tumor microenvironments. The nanocarriers can be effectively taken up by A549 cells (a carcinomic human alveolar basal epithelial cell line), resulting in a high DOX intracellular accumulation and an improved anticancer cytotoxicity when compared with free DOX, suggesting their potential as a nanoplatform for therapeutic delivery.
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http://dx.doi.org/10.1016/j.msec.2019.03.028DOI Listing
July 2019

Comparative transcriptomics reveals potential genes involved in the vegetative growth of .

3 Biotech 2019 Mar 13;9(3):81. Epub 2019 Feb 13.

1Institute of Applied Mycology, Huazhong Agricultural University, 430070 Wuhan, China.

True morels ( spp.) are edible, medicinal mushrooms which have recently been artificially cultivated in China but stable production remains a problem. Here, we describe complete and comprehensive transcriptome of at the stages of vegetative mycelium (VM), initial sclerotium (IS) and mature sclerotium (MS) by deep transcriptional sequencing and assembly for the first time and which will potentially provide useful information for improving its cultivation. A total of 26,496 genes were identified with a contig N50 length of 1763 bp and an average length of over 1064 bp. Additionally, 11,957 open reading frames (ORFs) were predicted and 9676 of them (80.9%) were annotated. The 2605 differentially expressed genes (DEGs) identified by gene expression clustering were mainly involved with energy metabolism and could be divided into three broad clusters, of which genes in cluster_1 and cluster_2 were involved in the metabolic process of carbohydrate, polysaccharide, hydrolase, caprolactam, beta-galactosidase, and disaccharide, respectively. Genes in cluster_3 were the largest category, mainly identified with the catalytic activity and transporter activity. Overall, the enzymes involved in the carbohydrate metabolism were highly expressed, and the CAZyme (carbohydrate-active enzyme) genes were significantly expressed within cluster_3. For expression verification, 16 CAZYme genes were selected for qRT-PCR, and the results suggested that the catabolism of carbohydrates occurs mainly in the vegetative mycelium stage, and the anabolism of the energy-rich substances is the main event of mycelial growth and sclerotial morphogenesis of .
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http://dx.doi.org/10.1007/s13205-019-1614-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6374242PMC
March 2019

Preparation of thermo/redox/pH-stimulative poly(N-isopropylacrylamide-co-N,N'-dimethylaminoethyl methacrylate) nanogels and their DOX release behaviors.

J Biomed Mater Res A 2019 06 31;107(6):1195-1203. Epub 2019 Jan 31.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China.

Stimuli-sensitive drug delivery systems show beneficial features of both medical and pharmaceutical fields. In this article, polymeric nanogel P (N-isopropylacrylamide-N,N '-dimethylaminoethyl methacrylate [NIPAM-DMAEMA]) (PND) with pH/redox/thermo-responsivenesses was synthesized by the in situ polymerization of NIPAM and DMAEMA for the controlled release of doxorubicin hydrochloride (DOX) and N,N '-bis(acryloyl)cystamine (BAC) and N,N '-methylenebisacrylamide (MBA) act as the crosslinkers, respectively. The structure, size, and zeta potential of PND-BAC and PND-MBA were further characterized. Moreover, after loading DOX, the encapsulation efficiency and the in vitro release behavior of PND-BAC/DOX and PND-MBA/DOX nanogels were discussed in detail. Compared to PND-MBA NGs, PND-BAC nanogels have redox degradability due to the presence of the crosslinker BAC. After loading DOX, the PND-BAC/DOX nanogel showed a higher encapsulation efficiency (81.6 ± 1.2)% and thermo- and pH-responsiveness as well as redox-responsive in vitro release. These properties together with excellent environmentally sensitive properties make PND-BAC as an attractive candidate for application in drug nanocarriers for the targeted drug delivery of model payloads. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1195-1203, 2019.
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http://dx.doi.org/10.1002/jbm.a.36611DOI Listing
June 2019

Effect of Aging on Culture and Cultivation of the Culinary-Medicinal Mushrooms Morchella importuna and M. sextelata (Ascomycetes).

Int J Med Mushrooms 2019 ;21(11):1089-1098

Minquan Bureau of Agriculture and Animal Husbandry, Minquan 436800, China.

The prominent problem of "uncertainty" has been frustrating morel farming since the commercial production of Morchella mushrooms was realized in 2012 in China. Spawn aging may be the main underlying reason. In this paper, aging in cultivated strains of M. importuna T4 and M. sextelata T6 was achieved by successive subculturing. Oxidative stress, mycelial growth rate, biomass, sclerotial formation, pigmentation, and yield of different subcultures were determined. The results suggested that M. importuna T4 and M. sextelata T6 exhibited systemic senescence manifested as 24 and 17 subcultures and lifespan of 3048 and 2040 h, respectively. Aging showed a close relevance to oxidative stress. Regression analysis revealed a strong positive correlation between time of subculturing (aging) and lipid peroxidation (oxidative stress) in both morels. In addition, pigmentation tended to increase, while the number of sclerotia tended to decrease, with the rise of subculturing times in both morels. Moreover, the mycelial growth rate and biomass of the last two subcultures were significantly lower than those of others, indicating that cultural characteristics may be used as signs of seriously aging culture. Finally, the yield of subcultures was significantly lower than that of the original strains in artificial cultivation. Regression analysis showed a strong negative correlation between time of subculturing and yield in two morels. This work will improve the understanding of "uncertainty" and thus be beneficial for stable development of morel farming.
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http://dx.doi.org/10.1615/IntJMedMushrooms.2019032891DOI Listing
June 2020

Hybridization of graphene oxide into nanogels to acquire higher photothermal effects for therapeutic delivery.

Nanotechnology 2019 Mar 17;30(11):115701. Epub 2018 Dec 17.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, People's Republic of China.

Although the special architecture of two-dimensional (2D) nanomaterials endows them with unique properties, their poor colloidal stability remains a main bottleneck to fully exploit their applications in the biomedical field. Herein, this study aims to develop a simple and effective approach to in situ incorporate 2D graphene oxide (GO) nanoplatelets into a thermosensitive matrix to acquire hybrid nanogels with good stability and photothermal effect. In order to improve its stability, GO firstly underwent silanization to its surface with double bonds, followed by intercalation with N-isopropylacrylamide (NIPAM) in the presence of a disulfide-containing crosslinker via an emulsion method. Radical polymerization was then initiated to accelerate direct GO exfoliation in PNIPAM nanogels by forming covalent bonds between them. The well-dispersed GO nanopletlets in the nanogels not only displayed an enhanced photothermal effect, but also improved the encapsulation efficiency of an anticancer drug. The hybrid nanogels accelerate drug release under conditions mimicking the acidic/reducible solid tumor and intracellular microenvironments, most importantly, it can be further enhanced via remote photothermal treatment. The multifunctional nanogels potentiate their synergistic anticancer bioactivity as an ideal nanoplatform for cancer treatment.
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http://dx.doi.org/10.1088/1361-6528/aaf8e4DOI Listing
March 2019

Involvement of autophagy and apoptosis and lipid accumulation in sclerotial morphogenesis of Morchella importuna.

Micron 2018 06 21;109:34-40. Epub 2018 Mar 21.

Institute of Applied Mycology, Huazhong Agricultural University, Wuhan 430070, China. Electronic address:

Sclerotial formation is a key phase of the morel life cycle and lipids have been recorded as the main cytoplasmic reserves in sclerotia of Morchella fungi without any experimental verification. In this study, the ultrastructural features of the undifferentiated mycelia stage (MS) and three main sclerotial differentiation states (sclerotial initial [SI], sclerotial development [SD] and sclerotial maturation [SM]) were compared by transmission electron microscopy. The nature of the energy-rich substance in hypha and sclerotium of Morchella importuna was qualitatively investigated by confocal laser scanning microscopy and quantitatively studied by extraction of lipids. Sclerotia were observed to form from the repeated branching and enlargement of either terminal hyphae or subordinate hyphal branches, indicating a complex type of sclerotial development. Autophagy and apoptosis were involved in the sclerotial metamorphosis of the cultivated strain of M. importuna. During the SI phase, the characteristic features of autophagy (vacuolation, coalescence of small vacuoles, existence of autophagosomes and engulfment of autophagosomes by vacuoles) were observed. At the SD phase, apoptotic characteristics (condensation of the cytoplasm and nucleus, shrinkage of plasma membrane, extensive plasma membrane blebbing and existence of phagosomes) could be seen in some developing sclerotial cells. In the final stage of sclerotial morphogensis, the sclerotial cells showed a necrotic mode of cell death. In addition, confocal laser imaging studies of live cells indicated that the energy-rich substance in morel hyphae and sclerotia was lipid. The lipid content in sclerotia was significantly more than that in hyphal cells. To the best of our knowledge, this is the first detailed ultrastructural description highlighting the involvement of autophagy and apoptosis in sclerotial metamorphosis of Morchella species and lipid accumulation during morel sclerotial development was also first experimentally verified. This work will promote a better understanding of the mechanism of morel sclerotial metamorphosis.
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http://dx.doi.org/10.1016/j.micron.2018.03.005DOI Listing
June 2018

Multistimulative Nanogels with Enhanced Thermosensitivity for Intracellular Therapeutic Delivery.

ACS Appl Mater Interfaces 2017 Nov 3;9(45):39143-39151. Epub 2017 Nov 3.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University , Wuhan 430062, People's Republic of China.

The flexibility and hydrophilicity of nanogels suggest their potential for the creation of nanocarriers with good colloidal stability and stimulative ability. In the present study, biocompatible AGP and AGPA nanogels with triple-stimulative properties (thermosensitivity, pH sensitivity, and redox sensitivity) were prepared by incorporating poly(N-isopropylacrylamide) (PNIPAM) or poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-AA)) into alginate (AG) emulsion nanodrops, followed by fixation with a disulfide-containing molecule (cystamine dihydrochloride (Cys)). Compared to AG/PNIPAM(AGP) nanogels, AG/P(NIPAM-AA) (AGPA) nanogels exhibited more sensitive volumetric expansion by switching the temperature from 40 to 25 °C under physiological medium. This expansion occurs because P(NIPAM-AA) with -COOH groups can be fixed inside the nanogels via chemical bonding with Cys, whereas PNIPAM was encapsulated in the nanogels through simple physical interactions with the AG matrix. AGPA nanogels carrying an anticancer drug tend to easily enter cells upon heating, thereby exerting toxicity through a cold shock and reverse thermally induced release of an anticancer drug. Upon internalization inside cells, the nanogels use the reducible and acidic intracellular environments to effectively release the drug to the nucleus to impart anticancer activity. These results demonstrate that multifunctional nanogels may be used as a general platform for therapeutic delivery.
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http://dx.doi.org/10.1021/acsami.7b08209DOI Listing
November 2017

Effect of carbon source on production, characterization and bioactivity of exopolysaccharide produced by Phellinus vaninii Ljup.

An Acad Bras Cienc 2017 16;89(3 Suppl):2033-2041. Epub 2017 Oct 16.

College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450002 Henan, P.R. China.

The effect on different three carbon source (i.e. glucose, fructose and sucrose) on production, chemical characterization and antioxidant activity of exopolysaccharide (EPS) produced by Phellinus vaninii Ljup was investigated in this study. Amongst carbon sources examined, glucose and sucrose were favorable for the mycelia growth, while the maximum EPS yield was achieved when sucrose was employed. The predominant carbohydrate compositions in EPSs identified were gluconic acid, glucose, mannose and galactose acid. Then, FT-IR spectral analysis revealed prominent characteristic groups in EPSs. EPSs molecule exist as nearly globular shape form in aqueous solution. The variation also affects antioxidant activities by investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was best carbon source from the viewpoint of antioxidant activity due to the relatively high contents of galactose in the EPS with moderate molecular weight and polydispersity.
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http://dx.doi.org/10.1590/0001-3765201720150786DOI Listing
April 2018

Characterization and Antiproliferative Effect of Novel Acid Polysaccharides from the Spent Substrate of Shiitake Culinary-Medicinal Mushroom Lentinus edodes (Agaricomycetes) Cultivation.

Int J Med Mushrooms 2017 ;19(5):395-403

School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Food Production and Safety, Henan Province, Zhengzhou, China.

In this study, a high yield of crude polysaccharide (16.73 ± 0.756%) was extracted from the spent mushroom substrate of Lentinus edodes using a hot alkali extraction method. Two groups of polysaccharides (designated as LSMS-1 and LSMS-2) were obtained from the crude extract by size exclusion chromatography (SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index detector system. The weight-average molar masses of LSMS-1 and LSMS-2 were determined to be 6.842 × 106 and 2.154 × 106 g/mol, respectively. The SEC/MALLS analysis revealed that the molecular shapes of LSMS-1 and LSMS-2 were sphere-like forms in aqueous solution. Carbohydrate composition analysis using chromatography--mass spectrometry revealed that they were both acid heteropolysaccharides. LSMS-1 comprised mainly glucose and galacturonic acid, whereas LSMS-2 mainly consisted of xylose and glucuronic acid. Fourier transform infrared spectral analysis of the purified fractions revealed typical characteristic polysaccharide groups. In addition, MTT assays with refined polysaccharide doses of 25, 50, 100, 200, and 400 µg/mL suggested that both of the polysaccharide fractions exhibited antiproliferative activity against 6 tested human tumor cell lines in a concentration-dependent manner, and LSMS-2 had better anticancer capacity in vitro than LSMS-1. The inhibition ratio of LSMS-2 against A549 human lung cancer cells, the SGC7901 gastric cancer cell line, MCF-7 breast cancer cells, the U937 histiocytic lymphoma cell line, and the MG-63 human osteosarcoma cell line reached 43.55%, 29.97%, 19.63%, 18.24%, and 17.93%, respectively, at a concentration of 400 µg/mL.
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http://dx.doi.org/10.1615/IntJMedMushrooms.v19.i5.20DOI Listing
April 2018

Live cell confocal laser imaging studies on the nuclear behavior during meiosis and ascosporogenesis in Morchella importuna under artificial cultivation.

Micron 2017 Oct 29;101:108-113. Epub 2017 Jun 29.

School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, China; Institute of Applied Mycology, Huazhong Agricultural University, Wuhan 430070, China. Electronic address:

The commercial production of Morchella mushrooms, especially M. importuna, has been realized since 2012 in China, which facilitates the fundamental studies of Morchella spp. In this paper, the cytological characteristics at three stages of ascocarpic development and the nuclear behavior during meiosis and ascosporogenesis in cultivated strain M. importuna 1 was visualized by confocal laser scanning microscopy. The results suggested that the strain sporulated at sporulation stage of ascocarpic development. A total of six nuclear divisions typically took place during ascosporogenesis. The first and second divisions were meiotic in which the single diploid nucleus divided into four haploid nuclei. The subsequent mitosis gave rise to eight nuclei, and eight incipient ascospores with one nucleus in each spore were formed after spore delimitation in the clavate ascus. Then, the nucleus in most of the young ascospore underwent three successive mitoses producing 6-8 haploid nuclei in each mature spore, and thus the multinucleate ascospores in each ascus were all homokaryons. To the best of our knowledge, this is the first dynamic tracing study of nuclear behavior during meiosis and ascosporogenesis in cultivated morels, and the spore delimitation time is also the first report. The study will be beneficial for the genetics study and strain breeding of Morchella mushrooms.
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http://dx.doi.org/10.1016/j.micron.2017.06.012DOI Listing
October 2017

Study on β-cyclodextrin-complexed nanogels with improved thermal response for anticancer drug delivery.

Mater Sci Eng C Mater Biol Appl 2017 Sep 19;78:773-779. Epub 2017 Apr 19.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, People's Republic of China. Electronic address:

For achievement of controllability in drug delivery, development of nanocarriers with thermal response is one of the most investigated stimulative strategies for oncological treatment. How to improve the thermosensitivity of the nanocarriers is an important factor for their successful drug delivery applications. In this study, a kind of complexed nanogels (PNACD) was developed by incorporating β-cyclodextrin (β-CD) into the nanogels of copolymers of N-isopropylacrylamide (NIPAM) and acrylic acid (AA) during their polymerization via in situ crosslinking of N,N'-methylenebisacrylamide (MBA) as a crosslinker. The complexed PNACD nanogels displayed a significantly enhanced thermosensitivity near body temperature compared to the β-CD-free nanogels (PNA), which is probably associated with the rapid volumetric transformation during heating/cooling process due to the formation of complexed (decomplexed) structure between β-CD and PNIPAM element. The PNACD nanogels can be used for loading of an anticancer drug (doxorubicin, DOX) with an encapsulation efficiency of 54±5%. The DOX-loaded nanogels displayed pH-/thermo-dual responsivenesses in drug release, which can be effectively internalized into KB cells (a human epithelial carcinoma cell line) to exert good anticancer bioactivity. This approach may enlighten design of novel nanocarriers for delivery of drugs beyond anticancer chemotherapeutic reagents.
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http://dx.doi.org/10.1016/j.msec.2017.04.096DOI Listing
September 2017

Stimulative nanogels with enhanced thermosensitivity for therapeutic delivery via β-cyclodextrin-induced formation of inclusion complexes.

Carbohydr Polym 2017 Jun 1;166:219-227. Epub 2017 Mar 1.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China. Electronic address:

To explore the potential biomedical application of thermoresponsive nanosystems, it is important to enhance their thermosensitivity to improve the controllability in delivery of therapeutic agents. The present work develops multifunctional nanogels with enhanced thermosensitivity through copolymerization of N-isopropylacrylamide (NIPAM) and acrylic acid (AA) in the presence of β-cyclodextrin (β-CD), using N,N'-bis(acryloyl)cystamine (BAC) as a biodegradable crosslinker. The resulting nanogels display significantly improved sensitivity in deswelling (swelling) behavior upon temperature increase (decrease) around body temperature. The nanogels can effectively encapsulate doxorubicin (DOX), which can be released in an accelerated way under microenvironments that mimic intracellular reductive conditions and acidic tumor tissues. Release can also be remotely manipulated by increasing temperature. In vitro study indicates that the nanogels are quickly taken up by KB cells (a human epithelial carcinoma cell line), exerting improved anticancer cytotoxicity, showing their potential for delivery of therapeutic agents beyond anticancer drugs.
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http://dx.doi.org/10.1016/j.carbpol.2017.02.107DOI Listing
June 2017

Effect of Tween 80 and Acetone on the Secretion, 
Structure and Antioxidant Activities of Exopolysaccharides from .

Food Technol Biotechnol 2016 Sep;54(3):290-295

School of Food and Biological Engineering, Zhengzhou University of Light Industry,
Zhengzhou 450001, PR China; Collaborative Innovation Center of Food Production and Safety, Henan Province,
Zhengzhou 450001, PR China.

In this study, the effects of the addition of Tween 80 and acetone on secretion, structure and antioxidant activities of exopolysaccharides (EPS) were investigated. It was found that Tween 80 and acetone displayed a stimulatory effect on EPS secretion. The EPS obtained by the addition of Tween 80 (EPS-T), acetone (EPS-A) and control (EPS--C) were purified by Sepharose CL-6B gel filtration chromatography and molecular mass of purified fractions was estimated to be 22.1, 137 and 12 kDa, respectively. Monosaccharide composition analysis indicated that EPS-T, EPS-A and EPS-C were mainly composed of glucose and mannose. Congo Red test indicated that EPS-T and EPS-A had a highly ordered conformation of triple helix, while EPS-C had a random coil conformation. Furthermore, EPS-A exhibited higher DPPH scavenging and antiproliferative activities than EPS--C and EPS-T, which might be attributed to the molecular mass.
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http://dx.doi.org/10.17113/ftb.54.03.16.4211DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5151215PMC
September 2016

Endothelium-Independent Hypoxic Contraction Is Prevented Specifically by Nitroglycerin via Inhibition of Akt Kinase in Porcine Coronary Artery.

Stem Cells Int 2016 29;2016:2916017. Epub 2015 Dec 29.

Department of Physiology and Pathophysiology, Peking University Health Science Center, 38 Xue Yuan Road, Beijing 100191, China; Key Laboratory of Molecular Cardiovascular Science (Peking University), Ministry of Education, Beijing, China.

Objective. Hypoxia-induced sustained contraction of porcine coronary artery is endothelium-independent and mediated by PI3K/Akt/Rho kinase. Nitroglycerin (NTG) is a vasodilator used to treat angina pectoris and acute heart failure. The present study was to determine the role of NTG in hypoxia-induced endothelium-independent contraction and the underlying mechanism. Methods and Results. Organ chamber technique was used to measure the isometric vessel tension of isolated porcine coronary arteries. Protein levels of phosphorylated and total Akt were determined by western blot. A sustained contraction of porcine coronary arteries induced by hypoxia was significantly reduced by NTG but not by isoproterenol. This contraction was also inhibited by DETA NONOate, 8-Br-cGMP, which can be reversed by ODQ, and Rp-8-Br-PET-cGMPS. The restored contraction was blocked by LY294002. The reduction of Akt-p at Ser-473 by NTG, DETA NONOate, and 8-Br-cGMP was significantly inhibited by ODQ, PKG-I. The decrease in Akt-p level by NTG and 8-Br-cGMP was prevented by calyculin A but not by okadaic acid. Conclusions. These results demonstrated that the endothelium-independent sustained hypoxic vasoconstriction can be prevented by NTG and that the inhibition of PI3K/Akt signaling pathway may be involved.
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http://dx.doi.org/10.1155/2016/2916017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4709768PMC
February 2016

Morphological and ultrastructural examination of senescence in Morchella elata.

Micron 2015 Nov 26;78:79-84. Epub 2015 Jul 26.

School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, China; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China.

In recent years, the artificial cultivation of Morchella mushrooms that belong to Elata Clade, including Morchella elata, has been developed rapidly in China. However, the prominent problem of spawn aging has been frustrating the morel farming. In this paper, aging in M. elata was achieved from 12 to 17 subcultures and lifespan of 1536-2256 h by successive subculturing. The lifespan can be roughly divided into juvenile phase and senescent phase with respect to the mycelia linear growth rate. After a certain period of rapid growth with almost constant rate at the juvenile phase, the isolate entered the senescent phase characterized by slow down of mycelia growth, producing pigments ahead of time and final death of the apical hyphae. The period of the senescent phase was definitely 240-288 h; while that of the juvenile phase was diverse relying on different isolates. Moreover, microscopic study showed that angles between the leading and primary hyphae increased constantly with aging. In senesced hyphal cells of M. elata, the typical characteristics of autophagy (enlargement of vacuoles and existence of organelles sequestrated lysosomes) and apoptosis (condensation of the cytoplasm and nuclear and plasmolysis) were observed. In addition, in the final stage of senescence, the apical hyphae collapsed with the plasma membrane and all the cellular organelles disrupted, indicated a necrotic mode of cell death. Taken together, these data revealed the involvement of autophagy, apoptosis and necrosis in senescence of M. elata. The characterization and molecular mechanism of autophagy, apoptosis and necrosis need further study and the systematic study of morel aging will be beneficial for the healthy development of morel farming.
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http://dx.doi.org/10.1016/j.micron.2015.07.010DOI Listing
November 2015

Thermo/redox/pH-triple sensitive poly(N-isopropylacrylamide-co-acrylic acid) nanogels for anticancer drug delivery.

J Mater Chem B 2015 May 29;3(20):4221-4230. Epub 2015 Apr 29.

Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, People's Republic of China.

The clinical application of doxorubicin (DOX), like other anticancer drugs, is limited by insufficient cellular uptake and the numerous drug resistance mechanisms existing in cells. The development of smart nanomaterials capable of carrying the drugs into the cells and of releasing them under the control of the microenvironment is an interesting approach that may increase the success of the anticancer drugs currently in use. Herein, we report an easy process to prepare biocompatible nanogels (NGs) with thermo/redox/pH-triple sensitivity, which are highly effective in the intracellular delivery of DOX. Redox-sensitive/degradable NGs (PNA-BAC) and nondegradable NGs (PNA-MBA) were prepared through in situ polymerization of N-isopropylacrylamide (NIPAM) and acrylic acid (AA) in the presence of sodium dodecyl sulfate (SDS) as a surfactant, using N,N'-bis(acryloyl)cystamine (BAC) as a biodegradable crosslinker or N,N'-methylene bisacrylamide (MBA) as a nondegradable crosslinker, respectively. After that, the cationic DOX drug was loaded into the NGs through electrostatic interactions, by simply mixing them in aqueous solution. Compared to nondegradable PNA-MBA NGs, PNA-BAC NGs not only presented a higher DOX drug loading capacity, but also allowed a more sustainable drug release behavior under physiological conditions. More importantly, PNA-BAC NGs displayed thermo-induced drug release properties and an in vitro accelerated release of DOX under conditions that mimic intracellular reductive conditions and acidic tumor microenvironments. The thermo/redox/pH multi-sensitive NGs can quickly be taken up by CAL-72 cells (an osteosarcoma cell line), resulting in a high DOX intracellular accumulation and an improved cytotoxicity when compared with free DOX and DOX-loaded nondegradable PNA-MBA NGs. The developed NGs can be possibly used as an effective platform for the delivery of cationic therapeutic agents for biomedical applications.
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http://dx.doi.org/10.1039/c5tb00468cDOI Listing
May 2015

Effect of Carbon Source on Properties and Antioxidant Potential of Exopolysaccharides Produced by Trametes robiniophila (Higher Basidiomycetes).

Int J Med Mushrooms 2015 ;17(2):179-86

College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan 450002, People's Republic of China.

The effects of carbon source on properties and antioxidant potential of exopolysaccharides (EPS) produced by Trametes robiniophila were investigated in this study. The results indicated that the EPS production varied with five different carbon sources. The predominant carbohydrate compositions in EPSs identified were glucose and mannose. Then, FT-IR spectral analysis revealed prominent characteristic groups in the EPSs. Furthermore, thermogravimetric analysis (TGA) indicated the EPS with lactose as the carbon source showed different degradation behavior as compared to the other four EPSs, probably due to larger ribose content as one of major monosaccharides in the EPS. The variation also affects the antioxidant activities investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was the best carbon source from the viewpoint of antioxidant activity due to the relatively high xylose content in the EPS.
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http://dx.doi.org/10.1615/intjmedmushrooms.v17.i2.90DOI Listing
December 2015

Production, preliminary characterization, and bioactivities of exopolysaccharides from Pleurotus geesteranus 5(#).

Prep Biochem Biotechnol 2013 ;43(1):108-22

College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, PR China.

The optimal culture conditions of exopolysaccharides (EPS) production in submerged culture medium by Pleurotus geesteranus 5(#) were determined using an orthogonal matrix method. The optimal defined medium (per liter) was 60.0 g maltose, 5.0 g tryptone, 1 mM NaCl, 5 mM KH(2)PO(4), and initial pH 6.0 at 28 °C. In the optimal culture medium, the maximum EPS production was 16.97 g/L in a shake flask. Two groups of EPSs (designated as Fr-I and Fr-II) were obtained from the culture filtrates by size exclusion chromatography (SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The approximate weight-average molar masses of the Fr-I and Fr-II of EPS were determined to be 3.263 × 10(4) and 5.738 × 10(3) g/mol, respectively. The low values of polydispersity ratio (1.176 and 1.124 for Fr-I and Fr-II, respectively) of EPSs mean that these EPS molecules exist much less dispersed in aqueous solution without forming large aggregates. Furthermore, the experiments in vitro indicated that P. geesteranus 5(#) EPS exhibit high antitumor and antioxidative effects.
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http://dx.doi.org/10.1080/10826068.2012.712078DOI Listing
May 2013

Fermentation optimization, characterization and bioactivity of exopolysaccharides from Funalia trogii.

Carbohydr Polym 2012 Jun 16;89(1):17-23. Epub 2012 Feb 16.

College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan 450002, PR China.

Optimization of culture conditions for exopolysaccharide (EPS) by Funalia trogii in submerged culture was investigated using one-factor-at-a-time method and uniform design (UD). Under the optimized conditions, the maximum concentration of EPS was 8.68 g/l. After EPS was deproteinized by Sevag method, two groups of EPSs (designated as Fr-I and Fr-II) were obtained from the culture filtrates by gel filtration chromatography on Sepharose CL-6B. Furthermore, EPSs were characterized by size exclusion chromatography (SEC) coupled with a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The weight-average molar masses of the Fr-I and Fr-II were determined to be 1.007 × 10(5) and 2.393 × 10(4)g/mol, respectively. The root mean square (RMS) radii for both peaks ranged from 9.7 to 10.8 nm with no clear trends. Pharmacology experiments indicated F. trogii EPS were useful to the therapy of free radical injury and cancer diseases.
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http://dx.doi.org/10.1016/j.carbpol.2012.01.093DOI Listing
June 2012

Production, characterization and antioxidant activity of exopolysaccharides from submerged culture of Morchella crassipes.

Bioprocess Biosyst Eng 2012 Oct 14;35(8):1325-32. Epub 2012 Mar 14.

College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, People's Republic of China.

The aim of this work was to investigate the fermentation optimization, molecular characterization, and antioxidant activity in vitro of exopolysaccharides (EPS) from Morchella crassipes in submerged culture. Firstly, an optimal medium for EPS production was obtained by single-factor experiment and central composite design as follows: maltose 44.79 g/L and tryptone 4.21 g/L. Then, one fraction of EPS was obtained from the culture filtrates by size exclusion chromatography and the molecular characteristics were examined by a multi-angle laser light scattering and refractive index detector system. The weight-average molar mass and the polydispersity ratio of the EPS fraction were revealed to be 1.961 × 10(4) g/mol and 1.838, respectively. FT-IR spectroscopy was used for obtaining vibrational spectra of the purified EPS fraction. Finally, the antioxidant activity of EPS was investigated and the relationship with molecular properties was discussed as well.
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http://dx.doi.org/10.1007/s00449-012-0720-6DOI Listing
October 2012

Production, purfication, molecular characterization and bioactivities of exopolysaccharides produced by the wine cap culinary-medicinal mushroom, Stropharia rugosoannulata 2# (higher Basidiomycetes).

Int J Med Mushrooms 2012 ;14(4):365-76

College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, 450002, P.R. China.

The optimal culture conditions of exopolysaccharides (EPS) production in submerged culture medium by Stropharia rugosoannulata 2# were determined using the orthogonal matrix method. The optimal defined medium (per liter) was 60.0 g sucrose, 6.0 g tryptone, 5 mM KH₂PO₄, and initial pH 7.0 at 28°C. In the optimal culture medium, the maximum EPS production was 9.967 g/L in shake-flask culture. One fraction of EPS was purified from the culture filtrates by size exclusion chromatography (SEC), and the molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The weight-average molar masses and the polydispersity ratio of the EPS fraction were determined to be 5.305 × 103 g/mol and 2.014, respectively. FTIR spectroscopy was used for obtaining vibrational spectra of the purified EPS fraction. The obvious characteristic absorption at 884.3 cm-1 revealed the existence of β configuration. Furthermore, the experiments in vitro indicated that S. rugosoannulata 2# EPS exhibit high antitumor and antioxidative effects.
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http://dx.doi.org/10.1615/intjmedmushr.v14.i4.40DOI Listing
June 2013

Addressable nanoelectrode membrane arrays: fabrication and steady-state behavior.

Anal Chem 2007 Feb;79(4):1474-84

Department of Chemistry and Biochemistry, New Mexico State University, MSC 3C, Las Cruces, New Mexico 88003, USA.

An addressable nanoelectrode membrane array (ANEMA) based on a Au-filled track-etched polycarbonate membrane was fabricated. The Au-filled membrane was secured to a lithographically fabricated addressable ultramicroelectrode (UME) array patterned with 25 regularly spaced (100 microm center to center spacing), 10 microm diameter recessed Pt UMEs to create 25 microregions of 10 microm diameter nanoelectrode ensembles (NEEs) on the membrane. The steady-state voltammetric behavior of 1.0 mM Ru(NH(3))(6)Cl(3) and 1.0 mM ferrocene methanol in 0.1 M KCl on each of the micro NEEs resulted in sigmoidal-shaped voltammograms which were reproducible across the ANEMA. This reproducibility of the steady-state current was attributed to the overlapping hemispherical diffusion layers at the Au-filled nanopores of each 10 microm diameter NEE of a ANEMA. The track-etched polycarbonate membranes were filled using a gold electroless deposition procedure into the 30 nm diameter pores in the membrane. Electrical connection between the Au-filled template array and the lithographic UME platform array was achieved by potentiostatic electrodeposition of Cu from an acidic copper solution into each of the 25 recessed Pt UMEs on the UME array platform. A multiplexer unit capable of addressing 64 individual micro NEEs on an ANEMA is described. ANEMAs have advantages of high reproducibility, facile fabrication, multitime reuse of lithographically fabricated UME arrays, and purely steady-state behavior.
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http://dx.doi.org/10.1021/ac0619534DOI Listing
February 2007