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1.
Nutrients ; 15(8)2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37111066

ABSTRACT

Mortality is the most clinically serious outcome, and its prevention remains a constant struggle. This study was to assess whether intravenous or oral vitamin C (Vit-C) therapy is related to reduced mortality in adults. Data from Medline, Embase, and the Cochrane Central Register databases were acquired from their inception to 26 October 2022. All randomized controlled trials (RCTs) involving intravenous or oral Vit-C against a placebo or no therapy for mortality were selected. The primary outcome was all-cause mortality. Secondary outcomes were sepsis, COVID-19, cardiac surgery, noncardiac surgery, cancer, and other mortalities. Forty-four trials with 26540 participants were selected. Although a substantial statistical difference was observed in all-cause mortality between the control and the Vit-C-supplemented groups (p = 0.009, RR 0.87, 95% CI 0.78 to 0.97, I2 = 36%), the result was not validated by sequential trial analysis. In the subgroup analysis, mortality was markedly reduced in Vit-C trials with the sepsis patients (p = 0.005, RR 0.74, 95% CI 0.59 to 0.91, I2 = 47%), and this result was confirmed by trial sequential analysis. In addition, a substantial statistical difference was revealed in COVID-19 patient mortality between the Vit-C monotherapy and the control groups (p = 0.03, RR 0.84, 95% CI 0.72 to 0.98, I2 = 0%). However, the trial sequential analysis suggested the need for more trials to confirm its efficacy. Overall, Vit-C monotherapy does decrease the risk of death by sepsis by 26%. To confirm Vit-C is associated with reduced COVID-19 mortality, additional clinical random control trials are required.


Subject(s)
Ascorbic Acid , COVID-19 , Adult , Humans , Cause of Death , Vitamins , Dietary Supplements
2.
Article in English | MEDLINE | ID: mdl-37042839

ABSTRACT

Six aerobic or facultative anaerobic, motile, Gram-stain-positive, catalase-positive and oxidase-negative strains (zg-Y453T, zg-Y324, zg-Y462T, zg-Y411, zg-Y809T and zg-Y786) were isolated from different faecal samples of Marmota himalayana from the Qinghai-Tibet Plateau. Pale yellow, round, raised and moist colonies appeared 48 h after incubation at 28 °C on brain-heart infusion plates supplemented with 5 % defibrinated sheep blood. According to the 16S rRNA gene sequence alignment, two strain pairs (zg-Y453T/zg-Y324 and zg-Y462T/zg-Y411) shared the highest similarities to Arthrobacter luteolus (99.5 and 99.2 %), and the other one (zg-Y809T/zg-Y786) to Arthrobacter citreus (99.5 %). Results of phylogenetic analysis based on the 16S rRNA gene and genome sequences showed that these six strains represented three separate species within the genus Arthrobacter. The average nucleotide identity and digital DNA-DNA hybridization values between the three novel type strains (zg-Y453T/zg-Y462T/zg-Y809T) and other known species in this genus were all below respective thresholds (70.2-81.5/19.6-24.2 %, 70.6-81.8/19.8-25.0 %, and 70.4-88.2/19.9-35.3 %). Although phylogenetically related, there were obvious chemotaxonomic and phenotypic differences: strain pair zg-Y462T/zg-Y411 had anteiso-C15 : 0 as the only major fatty acid; the three novel species had different dominant quinones, MK-8(H2) in strains zg-Y462T/zg-Y809T (74.8/81.1 %) and MK-8(H2)/MK-9(H2) (43.1/53.0 %) in zg-Y453T; similarly, the ability to reduce nitrate in strains zg-Y453T and zg-Y462T could differentiate them from zg-Y809T. All strains had diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol, but differed slightly in the types of unidentified glycolipids, phospholipids and lipids. Based on the results of these polyphasic taxonomic analyses, three novel species within the genus Arthrobacter are proposed, namely Arthrobacter caoxuetaonis sp. nov. (type strain, zg-Y453T=GDMCC 1.2809T=JCM 35173T), Arthrobacter zhangbolii sp. nov. (type strain, zg-Y462T=GDMCC 1.2880T=JCM 35170T) and Arthrobacter gengyunqii sp. nov. (type strain, zg-Y809T=GDMCC 1.2808T=JCM 35168T).


Subject(s)
Arthrobacter , Animals , Sheep , Tibet , Fatty Acids/chemistry , Marmota , Phylogeny , RNA, Ribosomal, 16S/genetics , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Sequence Analysis, DNA , Vitamin K 2 , Feces
3.
Acta Biomater ; 159: 324-337, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36706851

ABSTRACT

Collateral damage to healthy tissue, uneven heat distribution, inflammatory diseases, and tumor metastasis induction hinder the translation of high-temperature photothermal therapy (PTT) from bench to practical clinical applications. In this report, a multifunctional gold nanorod (GNR)-based nanosystem was designed by attaching siRNA against B7-H3 (B7-H3si), glucose oxidase (GOx), and hyaluronic acid (HA) for efficient low-temperature PTT. Herein, GOx can not only exhaust glucose to induce starvation therapy but also reduce the heat shock protein (HSP), realizing the ablation of tumors without damage to healthy tissues. Evidence shows that B7-H3, a type I transmembrane glycoprotein molecule, plays essential roles in growth, metastasis, and drug resistance. By initiating the downregulation of B7-H3 by siRNA, siRNA-GOx/GNR@HA NPs may promote the effectiveness of treatment. By targeting cluster of differentiation 44 (CD44) and depleting B7-H3 and HSPs sequentially, siRNA-GOx/GNR@HA NPs showed 12.9-fold higher lung distribution than siRNA-GOx/GNR NPs. Furthermore, 50% of A549-bearing mice in the siRNA-GOx/GNR NPs group survived over 50 days. Overall, this low-temperature phototherapeutic nanosystem provides an appropriate strategy for eliminating cancer with high treatment effectiveness and minimal systemic toxicity. STATEMENT OF SIGNIFICANCE: To realize efficient tumor ablation under mild low-temperature (42-45 â„ƒ) and RNA interference simultaneously, here we developed a multifunctional gold nanorod (GNR)-based nanosystem (siRNA-GOx/GNR@HA NPs). This nanoplatform can significantly inhibit tumor cell proliferation and induce cell apoptosis by downregulation of HSP90α, HSP70, B7-H3, p-AKT, and p-ERK and upregulation of cleaved caspase-9 at mild low-temperature due to its superior tumor homing ability and the combined effect of photothermal effect, glucose deprivation-initiated tumor starvation, and B7-H3 gene silence effect. It is believed that this multifunctional low-temperature photothermal nanosystem with efficient and specific anticancer properties, shows a potential application in clinical tumor treatment.


Subject(s)
Nanotubes , Neoplasms , Animals , Mice , Phototherapy , Temperature , Gold/pharmacology , RNA Interference , Neoplasms/therapy , RNA, Small Interfering/genetics , Glucose , Cell Line, Tumor
4.
Food Chem ; 400: 134007, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36055149

ABSTRACT

On-site screening of biotoxins is of great importance for food safety. A new electrochemical-biosensing strategy was constructed for ochratoxin A (OTA) detection by direct using ready-made commercial portable-glucose-meter (PGM). Aptamer against OTA was adopted as the recognition probe and pre-immobilized onto the sensing interface. The complementary biotin-modified probe was further decorated by hybridization. Biotinylated invertase was further introduced onto the sensing system with streptavidin, which also acted as the signal amplification unit. The invertase, which was depended on the amount of OTA, produced the glucose from sucrose in the sensing solution. The glucose could be directly and conveniently measured with PGM. Quantitative analysis of OTA was achieved with a linear range from 0.5 ng/mL to 10 ng/mL and detection limit of 0.45 ng/mL. Of significance, it has been successfully applied for OTA analysis in rice with satisfied recoveries. This unique PGM-based electrochemical platform reveals prospective potential in food safety monitoring.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Ochratoxins , Oryza , Aptamers, Nucleotide/chemistry , Biotin , Electrochemical Techniques , Glucose , Limit of Detection , Ochratoxins/analysis , Streptavidin , Sucrose , beta-Fructofuranosidase
5.
Emerg Microbes Infect ; 11(1): 2715-2723, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36287125

ABSTRACT

Between November 2021 and January 2022, four patients of community-acquired pneumonia were admitted to the hospitals in Lishui city, Zhejiang province, China. Their main clinical manifestations were fever and dry cough as well as radiographic infiltrate, but the empiric antimicrobial therapy or traditional Chinese medicine was not effective for their illness. Clinical specimens from the patients as well as environmental and poultry specimens were collected for the determination of the causative pathogen. The ompA gene and seven housekeeping genes of Chlamydia psittaci were successfully amplified from all the patients, and the sequences of each gene were identical to one another, suggesting that they were infected by the same strain of C. psittaci. A novel strain of C. psittaci (LS strain) was isolated from the bronchoalveolar lavage fluid of patient 2 and its whole genome was obtained. Phylogenetic analyses based on the whole-genome sequences showed that the isolate is most closely related to the strain (WS/RT/E30) identified as genotype E/B. In addition, The ompA gene and four housekeeping genes of C. psittaci were also amplified from two of four faeces samples of geese at the home of patient 2, and the sequences from geese were 100% identical to those from the patients. Accordingly, these cases could be attributed to a circulating C. psittaci strain of genotype E/B in the local geese. Therefore, there is an urgent need to strengthen the regional surveillance on C. psittaci among poultry and humans for prevention and control of the outbreak of psittacosis in the city.


Subject(s)
Chlamydophila psittaci , Community-Acquired Infections , Pneumonia , Psittacosis , Animals , Humans , Chlamydophila psittaci/genetics , Psittacosis/epidemiology , Psittacosis/veterinary , Geese , Phylogeny , China/epidemiology , Community-Acquired Infections/epidemiology , Genotype , Poultry
6.
Zhongguo Zhong Yao Za Zhi ; 46(15): 3998-4007, 2021 Aug.
Article in Chinese | MEDLINE | ID: mdl-34472277

ABSTRACT

To summarize and evaluate the efficacy and safety of Shenmai Injection in the treatment of viral myocarditis, shock, pulmonary heart disease, coronary heart disease, neutropenia and tumor chemotherapy, so as to provide supportive evidences for clinical rational use of Shenmai Injection. By searching literatures about studies on the systematic reviews on Shenmai Injection in treatment of viral myocarditis, shock, pulmonary heart disease, coronary heart disease, neutropenia and tumor chemotherapy from the main Chinese and English databases. Primary efficacy and safety outcome measures were selected for comparative analysis and summary, and the appraisal tool of AMSTAR 2 was used to evaluate the included studies.A total of 36 systematic reviews(published from 2005 to 2020) were included, involving viral myocarditis, shock, pulmonary heart disease, malignant tumor and coronary heart disease. The number of cases included in each type of the above diseases was 3 840, 2 484, 12 702, 28 036 and 27 082, respectively. The comparison results showed that, Shenmai Injection combined with conventional/western medicine treatment groups had better efficacy than conventional/western medicine groups alone in the prevention and treatment of the above five diseases. The main adverse reactions of Shenmai Injection reported in the included studies were facial flushing, rash, palpitation, etc., but the incidence was low and the general symptoms were mild, so no special treatment was needed. Therefore, the application of Shenmai Injection on the basis of conventional treatment or western medicine treatment had better prevention and treatment efficacy of the diseases. It was suggested that more multi-center and larger sample-size randomized controlled trials should be carried out in the future, and the relevant reporting standards should be strictly followed in systematic reviews, so as to improve the scientificity and transparency of the study.


Subject(s)
Drugs, Chinese Herbal , Pulmonary Heart Disease , Drug Combinations , Humans , Systematic Reviews as Topic
7.
Neural Plast ; 2021: 8706400, 2021.
Article in English | MEDLINE | ID: mdl-34221003

ABSTRACT

Neuroinflammation plays important roles in the pathogenesis and progression of altered neurodevelopment, sensorineural hearing loss, and certain neurodegenerative diseases. Hyperoside (quercetin-3-O-ß-D-galactoside) is an active compound isolated from Hypericum plants. In this study, we investigate the protective effect of hyperoside on neuroinflammation and its possible molecular mechanism. Lipopolysaccharide (LPS) and hyperoside were used to treat HT22 cells. The cell viability was measured by MTT assay. The cell apoptosis rate was measured by flow cytometry assay. The mRNA expression levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) were determined by quantitative reverse transcription polymerase chain reaction. The levels of oxidative stress indices superoxide dismutase (SOD), reactive oxygen species (ROS), catalase (CAT), glutathione (GSH), and malondialdehyde (MDA) were measured by the kits. The expression of neurotrophic factor and the relationship among hyperoside, silent mating type information regulation 2 homolog-1 (SIRT1) and Wnt/ß-catenin, and sonic hedgehog was examined by western blotting. In the LPS-induced HT22 cells, hyperoside promotes cell survival; alleviates the level of IL-1ß, IL-6, IL-8, TNF-α, ROS, MDA, Bax, and caspase-3; and increases the expression of CAT, SOD, GSH, Bcl-2, BDNF, TrkB, and NGF. In addition, hyperoside upregulated the expression of SIRT1. Further mechanistic investigation showed that hyperoside alleviated LPS-induced inflammation, oxidative stress, and apoptosis by upregulating SIRT1 to activate Wnt/ß-catenin and sonic hedgehog pathways. Taken together, our data suggested that hyperoside acts as a protector in neuroinflammation.


Subject(s)
Neurons/drug effects , Quercetin/analogs & derivatives , Signal Transduction/drug effects , Sirtuin 1/biosynthesis , Animals , Apoptosis/drug effects , Cell Line , Cytokines/blood , Drug Evaluation, Preclinical , Hedgehog Proteins/physiology , Inflammation , Lipopolysaccharides/pharmacology , Mice , Nerve Growth Factors/physiology , Neurons/metabolism , Oxidative Stress/drug effects , Quercetin/pharmacology , Sirtuin 1/genetics , Up-Regulation/drug effects , Wnt Signaling Pathway/drug effects
8.
Ying Yong Sheng Tai Xue Bao ; 32(2): 521-528, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33650361

ABSTRACT

The activity and stoichiometry of soil extracellular enzyme can provide a good indication for changes in soil nutrient availability and microbial demands for nutrients. However, it remains unclear how would nitrogen (N) deposition affect nutrient limitation of microbes in subtropical forest soils. We conducted a 5 years N addition experiment in a subtropical Phyllostachys pubescens forest. The soil nutrients and enzyme activities associated with carbon (C), N, and phosphorus (P) cycles were measured. We also examined the nutrient distribution of microorganisms using enzyme stoichiometry and vector analysis. The results showed that N addition significantly decreased the contents of soil soluble organic C and available P and increased that of available N. Furthermore, N addition significantly decreased ß-N-acetyl-glucosaminidase (NAG) activity and NAG/ microbial biomass carbon (MBC), and increased acid phosphatase (ACP) and ACP/MBC. The low and moderate N addition levels significantly increased enzyme C/P, vector length, and vector angle, but significantly decreased enzyme N/P. Results of redundancy analysis showed that the change in soil enzyme activity and enzymatic stoichiometry were mainly driven by soil available P content under N addition. In summary, N addition altered the microbial nutrient acquisition strategy, which increased nutrient allocation to P-acquiring enzyme production but reduced that to N-acquiring enzyme production. Moreover, N addition exacerbated the C and P limitation of soil microorganisms. Appropriate amount of P fertilizer could be applied to improve soil fertility of subtropical P. pubescens forest in the future.


Subject(s)
Nitrogen , Phosphorus , Carbon/analysis , China , Forests , Nitrogen/analysis , Phosphorus/analysis , Soil , Soil Microbiology
9.
Mikrochim Acta ; 188(3): 90, 2021 02 18.
Article in English | MEDLINE | ID: mdl-33598733

ABSTRACT

The design and construction of a novel magnetic resonance sensor (MRS) is presented for bisphenol A (BPA) detection. The MRS has been built based on the core component of magnetic Fe3O4 nanoparticles (~ 40 nm), which were uniformly distributed in nanoporous carbon (abbreviated as Fe3O4@NPC). The synthesis was derived from the calcination of the metal organic framework (MOF) precursor of Fe-MIL-101 at high temperature. Fe3O4@NPC was confirmed with enhanced transversal relaxation with r2 value of 118.2 mM-1 s-1, which was around 1.7 times higher than that of the naked Fe3O4 nanoparticle. This enhancement is attributed to the excellent proton transverse relaxation rate of Fe3O4@NPC caused by the reduced self-diffusion coefficient of water molecules in the vicinity of Fe3O4 nanoparticles in the nanoporous carbon. BPA antibody (Ab) and antigen (Ag)-ovalbumin (OVA) were immobilized onto the Fe3O4@NPC to form Ab-Fe3O4@NPC and Ag-Fe3O4@NPC, respectively. These two composites can cause the three-dimensional assembly of Fe3O4@NPC via immunological recognition. The presence of BPA can compete with antigen-OVA to combine with Ab-Fe3O4@NPC, thereby breaking the assembly process (disassembly). The difference in the change of the T2 value before and after adding BPA can thus be used to monitor BPA. The proposed MRS not only revealed a wide linear range of BPA concentration from 0.05 to 50 ng mL-1 with an extremely low detection limit of 0.012 ng mL-1 (S/N = 3), but also displayed high selectivity towards matrix interferences. The recoveries of BPA ranged from 95.6 to 108.4% for spiked tea π, and 93.4 to 104.7% for spiked canned oranges samples, respectively, and the RSD (n = 3) was less than 4.4% for 3 successive assays. The versatility of Fe3O4@NPC with customized relaxation responses provides the possibility for the adaptation of magnetic resonance platforms for food safety development. The magnetic Fe3O4 nanoparticles are uniformly dispersed in the nanoporous carbon (Fe3O4@NPC), which derived from the calcinating of the metal organic framework (MOF) precursor of Fe-MIL-101. And the magnetic Fe3O4@NPCs are adopted for the construction of magnetic resonance sensor (MRS) for bisphenol A (BPA) detection.


Subject(s)
Benzhydryl Compounds/analysis , Magnetite Nanoparticles/chemistry , Nanocomposites/chemistry , Phenols/analysis , Antibodies, Immobilized/immunology , Benzhydryl Compounds/immunology , Carbon/chemistry , Citrus sinensis/chemistry , Food Contamination/analysis , Limit of Detection , Magnetic Resonance Spectroscopy/methods , Phenols/immunology , Porosity , Tea/chemistry
10.
Theranostics ; 10(23): 10498-10512, 2020.
Article in English | MEDLINE | ID: mdl-32929362

ABSTRACT

Rationale: Current traditional treatment options are frequently ineffective to fight against ovarian cancer due to late diagnosis and high recurrence. Therefore, there is a vital need for the development of novel therapeutic agents. B7H3, an immune checkpoint protein, is highly expressed in various cancers, representing it a promising target for cancer immunotherapy. Although targeting B7H3 by bispecific T cell-engaging antibodies (BiTE) has achieved successes in hematological malignancies during recent years, attempts to use them for the treatment of solid cancers are less favorable, in part due to the heterogeneity of tumors. Sorafenib is an unselective inhibitor of multiple kinases currently being tested in clinical trials for several tumors, including ovarian cancer which showed limited activity and inevitable side effect for ovarian cancer treatment. However, it is able to enhance antitumor immune response, which indicates sorafenib may improve the efficiency of immunotherapy. Methods: We evaluated the expression of B7H3 in ovarian cancer using online database and validated its expression of tumor tissues by immunohistochemistry staining. Then, B7H3 expression and the effects of sorafenib on ovarian cancer cell lines were determined by flow cytometry. In addition, 2D and 3D ovarian cancer models were established to test the combined therapeutic effect in vitro. Finally, the efficiency of B7H3×CD3 BiTE alone and its combination with sorafenib were evaluated both in vitro and in vivo. Results: Our data showed that B7H3 was highly expressed in ovarian cancer compared with normal samples. Treatment with sorafenib inhibited ovarian cancer cell proliferation and induced a noticeable upregulation of B7H3 expression level. Further study suggested that B7H3×CD3 BiTE was effective in mediating T cell killing to cancer cells. Combined treatment of sorafenib and B7H3×CD3 BiTE had synergistic anti-tumor effects in ovarian cancer models. Conclusions: Overall, our study indicates that combination therapy with sorafenib and B7H3×CD3 BiTE may be a new therapeutic option for the further study of preclinical treatment of OC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , B7 Antigens/antagonists & inhibitors , Carcinoma, Ovarian Epithelial/therapy , Ovarian Neoplasms/therapy , Sorafenib/pharmacology , Animals , Antibodies, Bispecific/pharmacology , Antibodies, Bispecific/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , B7 Antigens/analysis , B7 Antigens/metabolism , CD3 Complex/antagonists & inhibitors , Carcinoma, Ovarian Epithelial/immunology , Carcinoma, Ovarian Epithelial/mortality , Carcinoma, Ovarian Epithelial/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Datasets as Topic , Drug Synergism , Female , HEK293 Cells , Humans , Kaplan-Meier Estimate , Lymphocytes, Tumor-Infiltrating/drug effects , Lymphocytes, Tumor-Infiltrating/immunology , Mice , Neoplasm Recurrence, Local , Ovarian Neoplasms/immunology , Ovarian Neoplasms/mortality , Ovarian Neoplasms/pathology , Ovary/pathology , Sorafenib/therapeutic use , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Xenograft Model Antitumor Assays
11.
Sci Rep ; 10(1): 8876, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32483369

ABSTRACT

Present study was designed to compared the total flavonoids and polyphenols contents and antibacterial activity of hawthorn extracts with different polarities as well as the underlying antibacterial mechanisms. The results showed that among all hawthorn extracts, methanol and ethanol extracts (ME and EE) exhibited high levels of total flavonoids and polyphenols contents, followed by acetone, ethyl acetate, trichloromethane and petroleum ether extracts. ME exhibited the strongest antibacterial activity against tested bacteria, especially Staphylococcus aureus with a 1.25 µg/mL of the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). Further analysis revealed that the main phenolic compounds from ME were epicatechin (281.6 mg/100 g DW), procyanidin B2 (243.5 mg/100 g DW), chlorogenic acid (84.2 mg/100 g DW) and quercetin (78.4 mg/100 g DW). The action mechanism of ME against S. aureus could be ascribed to ME damaging cell wall and cell membrane integrity, inhibiting intracellular enzyme activity, increasing reactive oxygen species (ROS), also changing expression of associated genes and then inducing apoptosis of S. aureus. In addition, the antimicrobial activity of ME against S. aureus has also been demonstrated to be efficient in the food matrix (whole milk).


Subject(s)
Anti-Bacterial Agents/chemistry , Crataegus/chemistry , Plant Extracts/chemistry , Anti-Bacterial Agents/pharmacology , Catechin/pharmacology , Cell Wall/drug effects , Cell Wall/physiology , Chlorogenic Acid/pharmacology , Chromatography, High Pressure Liquid , Crataegus/metabolism , Flavonoids/chemistry , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Membrane Potentials/drug effects , Microbial Sensitivity Tests , Phenols/chemistry , Plant Extracts/pharmacology , Reactive Oxygen Species/metabolism
12.
Ying Yong Sheng Tai Xue Bao ; 31(3): 753-760, 2020 Mar.
Article in Chinese | MEDLINE | ID: mdl-32537969

ABSTRACT

Phosphorus (P) is an important nutrient for plant and microbial growth. Soil P availabi-lity is poor in subtropical areas. Long-term heavy nitrogen (N) deposition might further reduce P availability. The experiment was performed in a Phyllostachys pubescens forest in Daiyun Mountain. The effects of N application on soil basic physical and chemical properties, soil P fractions, microbial biomass, and acid phosphomonoesterase activity were analyzed after three years of N application. The results showed that N application significantly increased NO3--N content and thus soil N availability, while it significantly reduced the percentage of decomposable organic P to total P, with the ratio of carbon (C) to organic P being over 200. The soil microbial biomass C, microbial biomass P, acid phosphomonoesterase, and the ratio of microbial biomass N to microbial biomass P and microbial biomass C to microbial biomass P were increased as the N application rate increased. There was a significant negative correlation between the percentage of decomposable organic P to total P and microbial biomass P. Consequently, N application enhanced soil P limitation and increased microbial P demand.


Subject(s)
Nitrogen , Phosphorus , Biomass , Carbon , China , Forests , Soil , Soil Microbiology
13.
Food Chem ; 328: 127081, 2020 Oct 30.
Article in English | MEDLINE | ID: mdl-32454260

ABSTRACT

Mycotoxin contaminations of tea have been considered serious problems. The presence of interfering substances presents enormous challenges to accurate detection of hazardous analytes in tea soups. In this work, we have carefully predicted, evaluated, and confirmed the matrix effects in tea that have an undesired influence on the detection of aflatoxin B1 (AFB1) in tea soups by lateral flow test strips (LFTS). After pretreatment of tea samples by simple dilution to change the acidic tea soups to alkaline environments, the matrix effects can be completely eliminated and the reliability of AFB1 analysis in tea soups can be effectively guaranteed. AFB1 contaminated samples of different tea soups can be accurately measured with detection limits down to 0.05 ppb. As the first pioneering report to study the matrix effects on AFB1 monitoring in tea soups by LFTS, we definitely expect this work to further widen the application of LFTS for hazard screening in food safety.


Subject(s)
Aflatoxin B1/analysis , Food Analysis/instrumentation , Food Contamination/analysis , Tea/chemistry , Limit of Detection , Reagent Strips/chemistry , Time Factors
14.
Int J Syst Evol Microbiol ; 70(6): 3665-3672, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32416735

ABSTRACT

Two novel Gram-stain-positive, irregular rod-shaped bacterial strains, dk3136T and dk3543, were isolated from the faeces of Tibetan gazelle (Procapra picticaudata) in the Qinghai-Tibet Plateau of PR China. The cells were aerobic, oxidase-negative and catalase-positive. Colonies were yellowish, circular without any observable aerial mycelium after culturing at 28 ℃ for 3 days on brain-heart infusion (BHI) agar with 5 % sheep blood. The cells grew optimally at 28 °C, pH 7.5 and with 1 % (w/v) NaCl on BHI agar supplemented with 5 % sheep blood. Phylogenetic analysis of the 16S rRNA gene sequences revealed that their nearest phylogenetic relative was Nocardioides solisilvae Ka25T (97.9 % similarity). The results of 16S rRNA gene sequence and phylogenetic/phylogenomic analyses illustrated that N. solisilvae Ka25T, Nocardioides gilvus XZ17T, Nocardioides houyundeii 78T and Nocardioides daphniae D287T were their nearest phylogenetic neighbours. The DNA G+C contents of strains dk3136T and dk3543 were 70.3 mol% and 70.4 mol%, respectively. Their genomes exhibit lower than threshold (95-96 %) average nucleotide identity to known species of the genus Nocardioides. ll-2,6-diaminopimelic acid was the diagnostic diamino acid and MK-8(H4) was the predominant respiratory quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The two strains had C18 : 1 ω9c, iso-C16 : 0 and C17 : 1 ω8c as the major fatty acids, and rhamnose and galactose as the main whole-cell sugars. On the basis of the results of our genotypic, phenotypic and biochemical analyses, we conclude that strains dk3136T and dk3543 represent a novel species in genus Nocardioides, for which the name Nocardioides jishulii sp. nov. is proposed. The type strain is dk3136T (=CGMCC 4.7570T=JCM 33496T=KCTC 49314T).


Subject(s)
Actinobacteria/classification , Antelopes/microbiology , Feces/microbiology , Phylogeny , Actinobacteria/isolation & purification , Animals , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Peptidoglycan/chemistry , Phospholipids/chemistry , Pigmentation , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Tibet , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
15.
Nat Prod Res ; 33(5): 746-749, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29172783

ABSTRACT

The influence of natural drying (ND), hot-air drying (HD), vacuum drying (VD), infrared drying (ID) and freeze drying (FD) on bioactive compounds and bioactivities of Isodon rubescens (Hemsl.) was investigated in this study. The results showed that different drying methods resulted in the differences in bioactive compositions' content, antioxidant and antibacterial activities of extracts from I. rubescens. FD sample possessed the highest content of total phenolics, total flavonoids and several main phenolic compounds, as well as the stronger antioxidant and antibacterial activities, followed by ND, HD and VD, the lowest for ID samples. For this reason, freeze drying would seem to be more advisable for the drying I. rubescens, and future studies could focus on the quality evaluation and optimising various drying parameters.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Desiccation/methods , Isodon/chemistry , Anti-Bacterial Agents/isolation & purification , Antioxidants/isolation & purification , China , Flavonoids/isolation & purification , Freeze Drying , Hot Temperature , Infrared Rays , Phenols/isolation & purification , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Extracts/chemistry , Vacuum
16.
Int J Syst Evol Microbiol ; 68(12): 3874-3880, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30362934

ABSTRACT

In the present study, we describe two novel Gram-stain-positive, irregular rod-shaped bacterial strains, 78T and 601, that had been isolated from the faeces of Tibetan antelopes at the Hoh Xil Nature Reserve, Qinghai-Tibet Plateau, China. The cells were aerobic, oxidase-negative and catalase-positive. When cultured on brain-heart infusion agar supplemented with 5 % sheep blood, colonies were cream in colour, circular, smooth and convex. Phylogenetic analysis based on the full-length 16S rRNA sequences revealed that type strain 78T and strain 601 belong to the genus Nocardioides, sharing the highest similarity to Nocardioides solisilvae JCM 31492T (98.3 %), Nocardioides gilvus XZ17T (97.4 %) and Nocardioides daejeonensis JCM 16922T (97.4 %). The average nucleotide identity values between the two novel strains and the three closely related type strains of the genus Nocardioides were lower than the 95-96 % threshold. The DNA G+C content of strains 78T and 601 were 71.2 and 71.3 mol% respectively. MK-8 (H4) was the predominant respiratory quinone and ll-2,6-diaminopimelic acid was the diagnostic diamino acid in its cell-wall peptidoglycan. Its polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The main whole-cell sugars were rhamnose, xylose and galactose and the major fatty acids (>10 %) were C17 : 1ω8c, iso-C16 : 0 and C18 : 1ω9c. These data supported the affiliation of strains 78T and 601 to genus Nocardioides. Based on evidence collected from the phenotypic, genotypic and phylogenetic analyses, we propose a novel species named Nocardioideshouyundeii sp. nov. The type strain is 78T (=CGMCC 4.7461T=DSM 106424T).


Subject(s)
Actinomycetales/classification , Antelopes/microbiology , Feces/microbiology , Phylogeny , Actinomycetales/genetics , Actinomycetales/isolation & purification , Animals , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Diaminopimelic Acid/chemistry , Fatty Acids/chemistry , Peptidoglycan/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sheep , Tibet
17.
Nat Prod Res ; 32(10): 1184-1188, 2018 May.
Article in English | MEDLINE | ID: mdl-28438032

ABSTRACT

The influence of natural, hot-air and infrared drying on chemical composition and bioactivity of lemon peel essential oil are investigated in this study. The results showed that drying resulted in losses or increases of some components or production of some new substances, but the d-limonene (59.52-70.01%) was found as the main component of essential oil. Drying brought about decreases in the yield, antioxidant and antibacterial activity of essential oil. However, the natural drying had little effect, while the hot-air and infrared drying resulted in significant decreases in these parameters, especially at the higher temperature. The yield was the lowest under hot-air drying (60 °C) and decreased by 78%, while infrared drying (60 °C) sample exhibited the lowest antioxidant and antibacterial activities. Infrared drying was easier to lead to the decrease in bioactivity than hot-air drying at the same temperature. These results provided the theoretical basis for drying lemon peel.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Plant Oils/chemistry , Plant Oils/pharmacology , Anti-Bacterial Agents/chemistry , Antioxidants/chemistry , Cyclohexenes/analysis , Desiccation , Hot Temperature , Limonene , Oils, Volatile/analysis , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Plant Oils/analysis , Terpenes/analysis
18.
J Chromatogr Sci ; 56(2): 108-114, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29045617

ABSTRACT

High-speed counter-current chromatography (HSCCC) combined with macroporous resin (MR) column was successfully applied to the isolation and purification of four flavonoid glycosides from the medicinal herb Lotus plumule (LP). A polar two-phase solvent system composed of ethyl acetate-n-butanol-water (1:2:3, v/v/v) was selected by high-performance liquid chromatography (HPLC) and run on a preparative scale where the lower aqueous phase was used as the mobile phase with a head-to-tail elution mode. Quercetin-3-O-ß-D-glucopyranoside (15 mg), isorhamnetin-3-O-ß-D-glucopyranoside (13 mg), apigenin 6-C-ß-D-glucopyranosyl-8-C-α-L-arabinopyranoside (18 mg) and apigenin 6,8-di-C-ß-D-glucopyranoside (48 mg) were obtained in a one-step HSCCC separation from 240 mg of the sample. The purity of each compound was over 95% as determined by HPLC. Chemical structures of the isolated compounds were identified by electrospray ionization mass spectrometry (ESI-MS-MS) and nuclear magnetic resonance (NMR) methods. Moreover, the four compounds were isolated from LP for the first time.


Subject(s)
Countercurrent Distribution/methods , Flavonoids/isolation & purification , Glycosides/isolation & purification , Nelumbo/chemistry , Plant Extracts/chemistry , Chromatography, High Pressure Liquid/methods , Flavonoids/analysis , Glycosides/analysis , Magnetic Resonance Spectroscopy , Plant Stems/chemistry , Spectrometry, Mass, Electrospray Ionization
19.
J Asian Nat Prod Res ; 20(12): 1116-1122, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29088926

ABSTRACT

Two new daphnane diterpenes named tianchaterpenes A and B were isolated from the roots of Stelleropsis tianschanica. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR analyses and HRESIMS. Compounds 1 and 2 were evaluated for their cytotoxic activities against HeLa and HCT-8 cell lines. The results showed that all compounds displayed weak cytotoxicities to the HeLa cells and were inactive to the HCT-8 cells.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Diterpenes/chemistry , Diterpenes/pharmacology , Plant Roots/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Cell Line, Tumor , Drug Screening Assays, Antitumor , Drugs, Chinese Herbal/chemistry , Humans , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Structure
20.
Zhongguo Zhong Yao Za Zhi ; 42(16): 3219-3224, 2017 Aug.
Article in Chinese | MEDLINE | ID: mdl-29171244

ABSTRACT

To provide molecular evidence for medical material identification, we analyzed the nucleotide sequence of ITS2, psbA-trnH gene in Morus genus plants and commercial products which were obtained from different places in Xinjiang. The sequence of ITS2 and psbA-trnH in fifty-one samples were amplified and sequenced, MEGA 6.0 was used to analyze the intra- and interspecific K-2P distances, neighbor-joining (NJ) tree was used to constructing clustering tree. ITS2 sequence analyzed results showed that there is no intra-specific variation among Morus alba, M. alba var. tatarica and M. nigra, but 13 variations sites were exist between M. alba and M. nigra and their inter-specific K-2P distances was 0.04, which indicated that there had significant variation in them. We didn't find informative variation sites between Morus genus plants and commercial products, and we also found that M. nigra can be distinguished from other two species by NJ Tree. PsbA-trnH analysis results showed there was only one variation site between M. alba and M. nigra, but insertion or deletion variation were remarkable evidence among M. alba, M. alba var. tatarica and M. Nigra. Inter-specific variation was accordance with intra-specific variation of commercial products. So ITS2 and psbA-trnH gene were important marker for M. alba, M. alba var. tatarica and M. nigra identification. This study provided important evidence for Uygur medicine identification and market supervision.


Subject(s)
DNA Barcoding, Taxonomic , Morus/classification , China , DNA, Plant/genetics , DNA, Ribosomal Spacer/genetics , Geography , Phylogeny , Plants, Medicinal/classification , Trees/classification
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