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Improved observation of colonized roots reveals the regulation of arbuscule development and senescence by drought stress in the arbuscular mycorrhizae of citrus
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作者 Xilong Yin Wei Zhang +3 位作者 Zengwei Feng Guangda Feng Honghui Zhu Qing Yao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期425-436,共12页
Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to dr... Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to drought stress, remain unclear, which is mainly due to the difficulty in clearing and staining lignified roots with the conventional method. Here, we improved the observation of colonized roots of citrus plants with the sectioning method, which enabled the clear observation of AM fungal structures. Furthermore, we investigated the effects of one week of drought stress on arbuscule development and senescence with the sectioning method. Microscopy observations indicated that drought stress significantly decreased mycorrhizal colonization (F%and M%) although it did not affect plant growth performance. Fluorescence probes (WGA 488 and/or Nile red) revealed that drought stress inhibited arbuscule development by increasing the percentage of arbuscules at the early stage and decreasing the percentages of arbuscules at the midterm and mature stages. Meanwhile, drought stress accelerated arbuscule senescence, which was characterized by the increased accumulation of neutral lipids. Overall, the sectioning method developed in this study enables the in-depth investigation of arbuscule status, and drought stress can inhibit arbuscule development but accelerate arbuscule senescence in the colonized roots of citrus plants. This study paves the way to elaborately dissecting the arbuscule dynamics in the roots of fruit tree species in response to diverse abiotic stresses. 展开更多
关键词 Arbuscular mycorrhizae CITRUS Drought stress Arbuscule development Arbuscule senescence Fruit tree species
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Tannins from Acacia mangium Bark as Natural Dyes for Textiles:Characteristics and Applications
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作者 Maya Ismayati Nissa Nurfajrin Solihat +3 位作者 Fifi Melinda Setiawati Wasrin Syafii Yuki Tobimatsu Deni Zulfiana 《Journal of Renewable Materials》 EI CAS 2024年第9期1625-1637,共13页
Tannins are capable of producing natural dyes with antioxidant and antibacterial propertis,while synthetic dyes are commonly used in the textile industry,causing environmental issues like water pollution.This research... Tannins are capable of producing natural dyes with antioxidant and antibacterial propertis,while synthetic dyes are commonly used in the textile industry,causing environmental issues like water pollution.This research aims to utilize waste tannins as natural dyes as an alternative to synthetic dyes.This study examined the effect of the extraction method on tannin properties such as phenolic content,antioxidants,and antibacterial activity.In addition,Pyrolysis Gas Chromatography‒Mass Spectrometry(Py-GCMS)analysis was used to identify the effect of extraction temperature on the chemical elucidation of tannin.The effect of tannin concentration was evaluated against four bacteria that are usually found on human skin:Staphylococcus epidermidis,Bacillus subtilis,Propionibacterium acnes,and Staphylococcus aureus.Extraction temperature significantly influences the chemical composition of tannin,which leads to different antioxidant properties.The maximum antibacterial properties of tannin were obtained at 90℃with the inhibition zone in the range of 0.9–1.0 mm against four bacteria,tannin yield of 26.59%,Gallic Acid Equivalents or total phenolic content(GAE)of 40.30 mg/g,and Radical Scavenging Activity or antioxidant activity(RSA)of 89.88%.Moreover,the concentration of tannin was significantly linear with its antibacterial properties.Tannin was successfully applied to the textile by using alum as a mordanting agent to create an antibacterial textile.The textile’s bacterial structure damage was analyzed under Field Emission Scanning Electron Microscopy(FESEM).After 50 washings,tannin-textiles with alum-modified properties remained stable compared to those without alum,with S.aureus and S.epidermidis being the most vulnerable bacteria,as confirmed by FESEM images.Hence,tannin is a feasible alternative to harmful and nondegradable synthetic dyes and antibacterial agents. 展开更多
关键词 Acacia mangium tannin ANTIBACTERIAL ANTIOXIDANT different temperature extraction DYES
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White Blood Cells Detection Using Spectral Tresholding 被引量:1
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作者 Kamara Ndèye Lama Boye Mouhamadou Moustapha Traore Ali 《Journal of Signal and Information Processing》 2023年第1期1-8,共8页
The study of the morphology of White Blood Cells (WBCs) further contributes to the clinical diagnosis of blood diseases. In this research paper, we come up with an image segmentation enhancement by combining Fourier F... The study of the morphology of White Blood Cells (WBCs) further contributes to the clinical diagnosis of blood diseases. In this research paper, we come up with an image segmentation enhancement by combining Fourier Fast Transform on smear blood capture and classical thresholding. The Fast Fourier Transform (FFT) is a very powerful tool in image processing and it was used to segment and extract the WBCs. Our image processing method uses a Fast Fourier Transform combined with filtering and an Inverse Fast Fourier Transform for the extraction and visualization of the high frequency region of the image. In order to remove residual Red Blood Cells acting as noise in the expected result, a final thresholding step is added at the end of the processing. The results presented in this article report the tests performed using our mathematical implementation. Moreover, we were able to detect and differentiate the sub-families of WBCs. 展开更多
关键词 SEGMENTATION Fourier Transform White Blood Cell
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流动电极微生物电合成提高产物生成速率及降低能量消耗
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作者 褚娜 王东麟 +5 位作者 王厚锋 梁勤军 常佳丽 高瑜 蒋永 曾建雄 《Engineering》 SCIE EI CAS CSCD 2023年第6期157-167,M0007,共12页
微生物电合成(microbial electrosynthesis,MES)利用可再生电力驱动微生物固定CO_(2)合成化学品,在推进碳循环经济中具有一定潜力,受到广泛关注。但是,很少有研究通过高效反应器设计来促进产乙酸并降低能耗。本研究中,新型流动电极MES... 微生物电合成(microbial electrosynthesis,MES)利用可再生电力驱动微生物固定CO_(2)合成化学品,在推进碳循环经济中具有一定潜力,受到广泛关注。但是,很少有研究通过高效反应器设计来促进产乙酸并降低能耗。本研究中,新型流动电极MES反应器的总产乙酸速率[(16±1)g·m^(-2)·d^(-1)]比无粉末活性炭(powder activated carbon,PAC)对照[(8±3)g·m^(-2)·d^(-1)]高两倍。流动电极MES反应器的库伦效率为43.5%±3.1%,能量消耗为(0.020±0.005)k Wh·g^(-1),产乙酸的能量效率为18.7%±1.3%。基于PAC的流动电极能够降低水跨膜通量、传质阻力,但是对装置电压、流变行为、乙酸吸附的影响较小。流动电极MES反应器中,能量代谢相关基因高表达,Acetobacterium的丰度增加。MES反应器中同时存在用于碳固定的还原性乙酰辅酶A途径(Wood–Ljungdahl pathway,WLP)与还原性三羧酸循环途径(reductive citric acid cycle,r TCA)。堆叠型流动电极MES中的乙酸浓度达7.0 g·L^(-1)。本研究提供一种构建可扩展MES反应器的新方法,促进CO_(2)利用以及产物生成。 展开更多
关键词 微生物电合成 乙酸浓度 能量消耗 三羧酸循环 传质阻力 生成速率 能量效率 粉末活性炭
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Ultra-Violet (UV): A Good Bacterial Sterilizer?
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作者 Sira Sidibe Mouhamadou Moustapha Boye +1 位作者 Maryam Mouhamadou Ali Traore 《Journal of Biosciences and Medicines》 CAS 2023年第2期80-85,共6页
Introduction: The aim of this study was to improve the DISTER-UV and to perform microbiological quality control at the biomedical laboratory of the West African Polytechnic University from January 2022 to November 202... Introduction: The aim of this study was to improve the DISTER-UV and to perform microbiological quality control at the biomedical laboratory of the West African Polytechnic University from January 2022 to November 2022. Methodology: During this eleven-month prospective study, we set up a quality control device (QCD). For microbiological quality control, we performed different cultures of bacteria with different bacteriological and morphological characteristics at T0 (no sterilization) and at T30 (after 30 minutes of sterilization under DISTER-UV). Results: After the realization, the DCQ attached to the DISTER-UV1 allows to display of the UV wavelength present in the light box. This device also displays and alerts when the UV intensity emitted by the lamps is below 250 nm. During microbiological quality control, the cultures carried out at T30 and incubated for 24 hours did not reveal any bacterial colonies. This shows the bactericidal character of DISTER-UV-2. Conclusion: The improvement and the microbiological quality control allowed us to switch from DISTER-UV1 (without sensor) to DISTER-UV-2 (with sensor or DCQ). The biological control allowed us to affirm that the DISTER-UV-2 is bactericidal. 展开更多
关键词 STERILIZATION Ultraviolet Radiation BACTERICIDE Quality Control BACTERIA
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Vitamin E modulates androgen receptor gene expression to attenuate ovarian dysfunctions in a rat model of dehydroepiandrosterone-induced polycystic ovary
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作者 Olugbemi T Olaniyan Ayobami Dare +4 位作者 Charles O.Adetunji Gloria E.Okotie Joseph B.Dare Bosun M.Adigun Femi Adebayo 《Asian pacific Journal of Reproduction》 2023年第2期81-89,共9页
Objective:To investigate the protective effect of vitamin E in dehydroepiandrosterone(DHEA)-induced polycystic ovary in rats.Methods:Premature female Wistar rats were randomly allocated into four groups,with 7 rats in... Objective:To investigate the protective effect of vitamin E in dehydroepiandrosterone(DHEA)-induced polycystic ovary in rats.Methods:Premature female Wistar rats were randomly allocated into four groups,with 7 rats in each group.Group栺received corn oil(vehicle)and served as the control group;group栻received 0.2 mL of 0.06 mg/g DHEA in corn oil;group栿received 200 mg/kg vitamin E;group桇received DHEA plus vitamin E.All treatments lasted for 15 days,with DHEA administered subcutaneously,while vitamin E and corn oil were administered orally.After the experiment,serum samples and ovaries were harvested for biochemical,immunohistochemical,hormonal,and histological analysis.The ovarian mRNA expression of androgen receptor was analyzed by reverse transcriptase quantitative polymerase chain reaction(qPCR).Results:The antioxidant and metabolic enzyme activity significantly decreased in the DHEA-treated rats compared to the control rats(P<0.05).Administration of vitamin E to DHEAtreated rats significantly decreased cytokines and malondialdehyde compared to the DHEA-treated rats.The histological analysis showed reduced atretic and cystic ovaries,increased E-cadherin and Bcl-2 expression,and reduced expression of Bax in the DHEAtreated rats co-treated with vitamin E.The mRNA expression of androgen receptor was upregulated in the DHEA-treated rats compared to the control rats.Conclusions:Vitamin E ameliorates the hyperandrogenic effect of DHEA-induced polycystic ovaries via metabolic,antioxidant,and anti-apoptotic pathways. 展开更多
关键词 DEHYDROEPIANDROSTERONE Metabolic markers Polycystic ovarian syndrome Vitamin E Wistar rats
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Biofilm analyses and exoproduct release by clinical and environmental isolates of Burkholderia pseudomallei from Brazil
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作者 Glaucia Morgana de Melo Guedes Crister JoséOcadaque +7 位作者 Alyne Soares Freitas Rodrigo Machado Pinheiro Giovanna Barbosa Riello Silviane Praciano Bandeira Rossana de Aguiar Cordeiro Marcos Fábio Gadelha Rocha JoséJúlio Costa Sidrim Débora de Souza Collares Maia Castelo-Branco 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第7期321-328,共8页
Objective:To characterize biofilm production by clinical(n=21)and environmental(n=11)isolates of Burkholderia pseudomallei and evaluate the production of proteases,hemolysins and siderophores.Methods:Initially,the 32 ... Objective:To characterize biofilm production by clinical(n=21)and environmental(n=11)isolates of Burkholderia pseudomallei and evaluate the production of proteases,hemolysins and siderophores.Methods:Initially,the 32 strains were evaluated for biofilm production in Müller-Hinton broth-1%glucose(MH-1%glucose)and BHI broth-1%glucose,using the crystal violet staining technique.Subsequently,growing(48 h)and mature(72 h)biofilms were evaluated by confocal microscopy.Finally,the production of proteases,hemolysins and siderophores by planktonic aggregates,growing biofilms and mature biofilms was evaluated.Results:All isolates produced biofilms,but clinical isolates had significantly higher biomass in both MH-1%glucose(P<0.001)and BHI-glucose 1%(P=0.005).The structural analyses by confocal microscopy showed thick biofilms,composed of multiple layers of cells,homogeneously arranged,with mature biofilms of clinical isolates presenting higher biomass(P=0.019)and thickness of the entire area(P=0.029),and lower roughness coefficient(P=0.007)than those of environmental isolates.Protease production by growing biofilms was significantly greater than that of planktonic(P<0.001)and mature biofilms(P<0.001).Hemolysin release by planktonic aggregates was higher than that of biofilms(P<0.001).Regarding siderophores,mature biofilms presented higher production than growing biofilms(P<0.001)and planktonic aggregates(P<0.001).Conclusions:Clinical isolates have higher production of biofilms than their environmental counterparts;protease and siderophores seem important for growth and maintenance of Burkholderia pseu­domallei biofilms. 展开更多
关键词 MANGOSTEEN Burkholderia pseudomallei Biofilms Proteases HEMOLYSINS SIDEROPHORES
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HIV-1 RNA Viral Load, CD4 Count and Some Haematological Parameters of People Living with HIV in the Enugu Metropolis
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作者 Izuchukwu Ibeagha Evelyn Ada Kyrian-Ogbonna +7 位作者 Felix Emelike Ekene Ibeagha Emmanuel Enyi Theresa Osarunwese Ifeyinwa Onochie-Igbinedion Harrison Abone Dorothy Ezeagwuna Chinwe Chukwuka Moses Ikegbunam 《World Journal of AIDS》 2023年第2期57-69,共13页
Background: It is widely known that the human immune-deficiency virus (HIV) induces biochemical and physiological changes in affected persons. Consequently, the overall aim of this study was to evaluate the HIV-1 RNA ... Background: It is widely known that the human immune-deficiency virus (HIV) induces biochemical and physiological changes in affected persons. Consequently, the overall aim of this study was to evaluate the HIV-1 RNA viral load, CD4 count, and certain haematological parameters among HIV treatment-na?ve subjects in the Enugu metropolis of Nigeria. Materials and Methods: A total of 252 HIV-infected, ART-native subjects (≥18) attending the University of Nigeria Teaching Hospital (UNTH) in Ituku-Ozalla, Enugu were recruited for this study and were made up of 157 (62.3%) females and 95 (37.7%) males. A total of 250 HIV-negative subjects were used as control subjects (100 males and 150 females). Blood samples were collected from all the participants and their HIV-1 status was confirmed by an immunoblot confirmatory test. Their haematological parameters and CD4 count were evaluated, while the HIV-1 viral load was only assessed on confirmed HIV-positive subjects. Results: There was female predominance (62.3%) among these HIV-positive subjects. The mean age of HIV-positive subjects was 39.16 ± 10.08 years while the mean age of the control subjects was 34.8 ± 8.6 years. The age group of 31 - 40 years (102/252 (40.5%)) constituted most of the test subjects. The total white blood cells (TWBC) (6.05 ± 5.46), lymphocyte counts (36 ± 14), haemoglobin concentrations (Hb) (9.85 ± 7.36) and the CD4 counts (242 ± 228) of the HIV-infected subjects showed a significant difference when compared with their control counterpart values of TWBC (4.5 ± 0.568), lymphocytes (39.67 ± 8.2), Hb (13.48 ± 1.5), and CD4 counts (807 ± 249) (p 0.05). Anaemia, lymphocytopenia, and thrombocytopenia were the haematological abnormalities seen in the HIV-positive subjects. HIV viral load correlated with haemoglobin concentration, CD4 count, lymphocyte count, and neutrophil count (p Conclusion: Prognostic factors, such as haemoglobin concentrations, CD4 counts, lymphocyte counts, and neutrophil counts can be used to monitor patients’ viral loads since they correlate with the latter;furthermore, age is a factor that should be considered in the management of HIV-positive patients. 展开更多
关键词 HIV-1 RNA CD4 Count Haematological Parameters
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从豆科植物的根瘤中直接提取根瘤菌DNA的方法 被引量:40
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作者 陈强 张小平 +3 位作者 李登煜 陈文新 K.Lindstrm Z.Terefework 《微生物学通报》 CAS CSCD 北大核心 2002年第6期63-67,共5页
豆科植物的新鲜根瘤经表面灭菌、破碎后直接加入 2 0 0 μL 4mol/L异硫氰酸胍 (GUTC)裂解液混匀 ,离心去掉根瘤残留物 ,再加入适量RNA酶 ,37℃温育 30min后 ,加入 2 0 μL硅藻土吸附液 ,室温处理 1 5min离心去掉上清 ,沉淀经GUTC裂解液... 豆科植物的新鲜根瘤经表面灭菌、破碎后直接加入 2 0 0 μL 4mol/L异硫氰酸胍 (GUTC)裂解液混匀 ,离心去掉根瘤残留物 ,再加入适量RNA酶 ,37℃温育 30min后 ,加入 2 0 μL硅藻土吸附液 ,室温处理 1 5min离心去掉上清 ,沉淀经GUTC裂解液二次处理 ,再分别用洗涤液、 70 %酒精洗涤。最后 ,硅藻土沉淀经真空干燥 ,加入 2 0 μL超纯水洗涤硅藻土沉淀 ,即可获得类菌体根瘤菌DNA。所获得的DNA可以用于AFLP、 1 6SrRNAPCR反应。 展开更多
关键词 豆科植物 直接提取 根瘤菌DNA AFLP指纹图谱
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水稻土中铁氧化物的厌氧还原及其对微生物过程的影响 被引量:40
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作者 曲东 张一平 +1 位作者 Schnell S Conrad R 《土壤学报》 CAS CSCD 北大核心 2003年第6期858-863,共6页
采用厌氧泥浆恒温培养实验 ,测定了添加 6种外源氧化铁后土壤中Fe(Ⅱ )和Fe(Ⅲ )浓度的变化 ,探讨了不同氧化铁的还原能力及其对土壤产H2 、产CO2 、产乙酸和产CH4 过程的影响。结果表明 :无定形氧化铁和纤铁矿易于被还原 ,两者的最终... 采用厌氧泥浆恒温培养实验 ,测定了添加 6种外源氧化铁后土壤中Fe(Ⅱ )和Fe(Ⅲ )浓度的变化 ,探讨了不同氧化铁的还原能力及其对土壤产H2 、产CO2 、产乙酸和产CH4 过程的影响。结果表明 :无定形氧化铁和纤铁矿易于被还原 ,两者的最终还原程度大体相同 ,但无定形氧化铁存在还原滞后现象 ;针铁矿、赤铁矿、Al取代针铁矿和Al取代赤铁矿难以被还原 ,表现出与对照相同的还原特征 ;铁还原能导致土壤中H2 和乙酸稳态浓度的降低 ,有效抑制了甲烷产生 ;添加Fe(OH) 3和纤铁矿后 ,Fe(Ⅲ )还原占总电子传递的贡献率由对照的 1 8.3 0 %增至 63 .3 2 %和 46.90 % ,而形成甲烷的电子传递贡献率由对照的 80 .92 %降至 3 5 .85 %和 5 2 .3 2 % ,Fe(Ⅲ )还原对电子的竞争消耗 。 展开更多
关键词 水稻土 铁氧化物 厌氧还原 微生物 影响因素 厌氧泥浆 恒温培养实验
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添加氧化铁对水稻土中H_2、CO_2和CH_4形成的影响 被引量:27
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作者 曲东 张一平 +1 位作者 S.Schnell R.Conrad 《应用生态学报》 CAS CSCD 2003年第8期1313-1316,共4页
水稻土是甲烷产生的重要源地 .厌氧条件下甲烷的形成与有机质厌氧降解产生的乙酸、H2 和CO2 有关 .氧化铁作为电子受体可有效地竞争有机质向甲烷的转化 ,其抑制作用机理可能与乙酸、H2 和CO2 的有效消耗有关 .通过向水稻土泥浆中添加无... 水稻土是甲烷产生的重要源地 .厌氧条件下甲烷的形成与有机质厌氧降解产生的乙酸、H2 和CO2 有关 .氧化铁作为电子受体可有效地竞争有机质向甲烷的转化 ,其抑制作用机理可能与乙酸、H2 和CO2 的有效消耗有关 .通过向水稻土泥浆中添加无定形氧化铁和纤铁矿 ,分别测定了 2 5℃厌氧恒温培养1 0 5d过程中的H2 、CO2 和CH4 的浓度变化 .结果表明 ,添加无定形氧化铁及纤铁矿可导致H2 浓度显著降低 ;无定形氧化铁对H2 消耗的影响明显大于纤铁矿 ;添加不同氧化铁对CO2 浓度的影响与H2 浓度的变化有相同的趋势 ;添加氧化铁能显著抑制水稻土中甲烷形成 ,并导致有机碳的转移发生变化 ,使得CH4 C显著降低 ,气相中CO2 C量减少 ,而由土壤泥浆固定的CO32 - 展开更多
关键词 水稻土 甲烷形成 氧化铁 二氧化碳
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短期淹水培养对水稻土中地杆菌和厌氧粘细菌丰度的影响 被引量:10
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作者 朱超 Stefan Ratering +1 位作者 曲东 Sylvia Schnell 《生态学报》 CAS CSCD 北大核心 2011年第15期4251-4260,共10页
模拟水稻土淹水过程,采用Real-time PCR技术测度了不同水稻土中地杆菌(Geobacteraceae spp.)和厌氧粘细菌(Anaeromyxobacter spp.)在不同淹水时期16S rDNA拷贝数的变化,比较了地杆菌和厌氧粘细菌丰度与培养过程中微生物Fe(Ⅲ)还原的关... 模拟水稻土淹水过程,采用Real-time PCR技术测度了不同水稻土中地杆菌(Geobacteraceae spp.)和厌氧粘细菌(Anaeromyxobacter spp.)在不同淹水时期16S rDNA拷贝数的变化,比较了地杆菌和厌氧粘细菌丰度与培养过程中微生物Fe(Ⅲ)还原的关系。结果表明,在4类稻作区采集的水稻土样品中,Fe(Ⅲ)还原潜势有明显的区别,表现出由北向南逐渐降低的趋势。从淹水12 h的地杆菌和厌氧粘细菌拷贝数变化看出,采自浙江和天津的水稻土样品对淹水过程具有高度敏感性,而采自吉林和广西的水稻土样品对淹水响应不敏感。在17 d的短期淹水培养中,地杆菌丰度明显高于厌氧粘细菌,表明地杆菌对水稻土中铁还原的贡献大于厌氧粘细菌。地杆菌和厌氧粘细菌拷贝数总体上表现出在11 d时达到峰值,17 d时显著下降。吉林水稻土中地杆菌丰度在5 d时达到38.3%,与其最大铁还原速率到达时间(TVmax)为4.07 d相对应,表明地杆菌对其铁还原过程具有重要贡献。四川水稻土中地杆菌和厌氧粘细菌丰度均较低,暗示其他兼性铁还原菌对其铁还原的作用值得重视。 展开更多
关键词 水稻土 地杆菌 厌氧粘细菌 丰度 REAL-TIME PCR
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外源氧化铁对水稻土中有机酸含量的影响 被引量:5
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作者 曲东 Sylvia Schnell Rolf Conrad 《应用生态学报》 CAS CSCD 2002年第11期1425-1428,共4页
在水稻土泥浆中添加Fe(OH) 3 可显著降低乙酸浓度 .在新鲜水稻土样品中 ,由于添加Fe(OH) 3导致对乙酸的竞争消耗 ,在培养 5d后 ,乙酸浓度降至 10~ 2 0 μmol·L-1的稳态浓度 ,而此刻对照中的乙酸浓度仍在 12 0 0 μmol·L-1以... 在水稻土泥浆中添加Fe(OH) 3 可显著降低乙酸浓度 .在新鲜水稻土样品中 ,由于添加Fe(OH) 3导致对乙酸的竞争消耗 ,在培养 5d后 ,乙酸浓度降至 10~ 2 0 μmol·L-1的稳态浓度 ,而此刻对照中的乙酸浓度仍在 12 0 0 μmol·L-1以上 .在乙酸产生量较低的土壤中 ,添加Fe(OH) 3 可完全消耗体系中的乙酸 ,并导致产CH4过程的完全被抑制 .添加纤铁矿同样可使乙酸浓度显著减少 ,但作用效果不如无定形氧化铁 .添加赤铁矿可造成培养初期 (10d以内 )乙酸的大量积累 ,但并不引起产CH4量的增大 .添加Fe(OH) 3 、纤铁矿及铝取代针铁矿 ,能引起厌氧培养的水稻土中丙酸浓度的降低 ,其抑制效率为Fe(OH) 3 >纤铁矿 >铝取代针铁矿 .新鲜土样和经过 11周厌氧处理后的土样中 ,有机酸种类和含量有较大差别 . 展开更多
关键词 外源氧化铁 水稻土 有机酸含量 脂肪酸浓度
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Insights into Cronobacter sakazakii Biofilm Formation and Control Strategies in the Food Industry 被引量:12
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作者 Na Ling Stephen Forsythe +3 位作者 Qingping Wu Yu Ding Jumei Zhang Haiyan Zeng 《Engineering》 SCIE EI 2020年第4期393-405,共13页
Cronobacter sakazakii(C.sakazakii)is a foodborne opportunistic pathogen that can cause life-threatening invasive diseases,such as necrotizing enterocolitis,meningitis,and sepsis in infants.The potential risk of C.saka... Cronobacter sakazakii(C.sakazakii)is a foodborne opportunistic pathogen that can cause life-threatening invasive diseases,such as necrotizing enterocolitis,meningitis,and sepsis in infants.The potential risk of C.sakazakii contamination of powdered infant formula(PIF)is an issue that has attracted considerable attention from manufacturers,regulators,and consumers.C.sakazakii biofilms on the surfaces of equipment and in diverse food-production environments constitute a mode of cell growth that protects the pathogen from hostile environments,and are an important source of persistent contamination of food products.Bacterial biofilms are difficult to remove due to their resistant properties.Conventional cleaning and sterilizing procedures may be insufficient for biofilm control,and may lead to further biofilm development and dispersal.Consequently,novel control strategies are being developed,such as nanotechnology-based delivery systems,interspecies interactions,antimicrobial molecules of microbial origin,natural extracts,and phages.This review focuses on describing the mechanisms underlying the biofilm formation and behavior of C.sakazakii and discussing potential control strategies. 展开更多
关键词 BIOFILM CONTROL Cronobacter sakazakii FORMATION REMOVAL
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基于文献计量学方法分析中国2005—2009年亚洲玉米螟的研究动态(英文) 被引量:10
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作者 蔡卓平 朱红惠 《浙江农业学报》 CSCD 北大核心 2012年第1期76-80,共5页
利用文献计量学方法分析2005—2009年间中文核心期刊上发表的亚洲玉米螟研究论文的数量、发表时间、研究主题、期刊分布、作者单位和资助课题等,探讨我国亚洲玉米螟近年的研究动态。结果表明,玉米螟研究是我国近年的热点课题。2005—200... 利用文献计量学方法分析2005—2009年间中文核心期刊上发表的亚洲玉米螟研究论文的数量、发表时间、研究主题、期刊分布、作者单位和资助课题等,探讨我国亚洲玉米螟近年的研究动态。结果表明,玉米螟研究是我国近年的热点课题。2005—2009年间在中文核心期刊上发表相关论文约62篇,其中2007年发表的论文篇数最多(21篇),其次为2009年(17篇);研究关注亚洲玉米螟的生物化学与分子遗传学(32.26%)、防治理论与技术(29.03%)、种群与繁殖行为(16.13%);发表相关论文最多的单位为中国农业科学院(15篇)、沈阳农业大学(11篇)和扬州大学(8篇);论文主要发表在《昆虫学报》(10篇)、《植物保护学报》(9篇)和《玉米科学》(6篇);标注项目资助的论文为56篇,而标注国家自然科学资金资助的论文为25篇。分析结果有助于多角度为读者和作者展示我国亚洲玉米螟研究的现状,为今后深入系统开展玉米螟研究提供参考。 展开更多
关键词 亚洲玉米螟 文献计量法 中国
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The aflatoxin B1 isolating potential of two lactic acid bacteria 被引量:9
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作者 Adel Hamidi Reza Mirnejad +5 位作者 Emad Yahaghi Vahid Behnod Ali Mirhosseini Sajad Amani Sara Sattari Ebrahim Khodaverdi Darian 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期732-736,共5页
Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for prevent... Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin Bl in human and animal bodies.Methods:In the present research,the bacteria were isolated from five different sources.For surveying the capability of the bacteria in isolating aflatoxin Bl,ELISA method was implemented,and for identifying the resultant strains through 16S rRNA sequencing method,universal primers were applied.Results:Among the strains which were isolated,two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin Bl by respectively absorbing and discharging 17.4%and 34.7%of the aforementioned toxin existing in the experiment solution.Conclusions:Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples,respectively.And both strains has the ability to isolate or bind with aflatoxin Bl. 展开更多
关键词 MYCOTOXIN AFLATOXIN LACTIC ACID BACTERIA ELISA test
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Extraction and Characterization of Antioxidant Compositions From Fermented Fruit Juice of Morinda citrifolia (Noni) 被引量:7
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作者 LIU Chang-hong XUE Ya-rong +3 位作者 YE Yong-hang YUAN Feng-feng LIU Jun-yan SHUANG Jing-lei 《Agricultural Sciences in China》 CAS CSCD 2007年第12期1494-1501,共8页
Extraction and characterization of antioxidative compositions from the extracts of fermented Xisha Noni (Morinda citrifolia L.) juice were studied. The antioxidative constituents of 184.6 g freeze-dried extracts of ... Extraction and characterization of antioxidative compositions from the extracts of fermented Xisha Noni (Morinda citrifolia L.) juice were studied. The antioxidative constituents of 184.6 g freeze-dried extracts of naturally fermented Xisha Noni juice were isolated successfully by petroleum ether, EtOAc and n-BuOH solvents, and the antioxidative effects were measured according to scavenging activity against hydroxyl generated in Fenton reaction system and superoxide anion radicals in pyrogallol autoxidation system. The EtOAc extract exhibited most significantly higher (P 〈 0.01) antioxidative activity than mannitol or vitamin C, while the petroleum ether and n-BuOH extracts showed lower activities compared to mannitol. Three antioxidant phenolic compounds, isoscopoletin, aesculetin and 3,3',4',5,7-pentahydroxyflavone (quercetin) were isolated from the EtOAc extract by several chromatography techniques for the first time. The results suggest that several compounds, in particular, the phenolic compounds, contribute separately or synergistically to the antioxidative activity of fermented Noni fruit juice. 展开更多
关键词 antioxidant activity Morinda citrifolia L. fermented fruit juice
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Caries-related factors and bacterial composition of supragingival plaques in caries free and caries active Algerian adults 被引量:3
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作者 Amina Hoceini Nihel Klouche Khelil +6 位作者 Ilhem Ben-Yelles Amine Mesli Sara Ziouani Lotfi Ghellai Nadia Aissaoui Fatima Nas Mounia Arab 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第8期720-726,共7页
Objective: To compare oral hygiene practices, education and social background, food intake and oral malodor of Algerian adults suffering from dental caries with normal controls, and to determine and compare the bacter... Objective: To compare oral hygiene practices, education and social background, food intake and oral malodor of Algerian adults suffering from dental caries with normal controls, and to determine and compare the bacterial composition of the supragingival plaques from the above-mentioned groups.Methods: Participants completed a questionnaire and were clinically examined for dental caries using decayed, missing and filled teeth index according to the criteria laid down by the World Health Organization. Supragingival plaque samples were collected from 50 caries-free adults(CF) and 50 caries-active adults(CA). Standard procedures of culture and identification of aerobic and anaerobic bacteria were used. Data were analyzed using Chi-square test.Results: A total of 117 bacterial strains were isolated from supragingival plaques in CF group subjects, 76(64.96%) of them belonged to 9 aerobic genera, and 41(35.04%) to 9anaerobic genera(P < 0.05). While in the second group, 199 strains were isolated, 119(59.80%) of the strains belonged to 10 aerobic genera and 80(40.20%) to 10 anaerobic bacteria(P < 0.05). Streptococcus mutans, Enterococcus faecium, Aerococcus viridans,Actinomyces meyeri, Lactobacillus acidophilus and Eubacterium limosum showed a significantly higher prevalence in the CA group(P < 0.05). The findings revealed that CA group had a high sugar intake(80%). A significantly higher frequency of tooth brushing(P < 0.000) and a significantly less self-reported oral malodor(P < 0.000) and tooth pain(P < 0.000) were found in CF group, while there was no association of socioeconomic levels and intake of meal snacks with dental caries.Conclusions: This study confirms the association of some aciduric bacteria with caries formation, and a direct association of sugar intake and cultural level with dental caries.Furthermore, oral hygiene practices minimize the prevalence of tooth decay. 展开更多
关键词 Supragingival plaque Caries-free Caries-active BACTERIAL COMPOSITION Algerian ADULTS Cultural level Food intake
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Composition and antimicrobial activity of Cistus munbyi essential oil: an endemic plant from Algeria 被引量:7
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作者 Fethi Benbelaid Abdelmounaim Khadir +3 位作者 Mourad Bendahou Mohamed Amine Abdoune Alain Muselli Jean Costa 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第6期1127-1132,共6页
The chemical composition and antimicrobial potential of Cistus munbyi essential oil were studied for the first time. GC and GC–MS analysis revealed 48 compounds representing 96.98% of the oil. Terpinen-4-ol(23.75%), ... The chemical composition and antimicrobial potential of Cistus munbyi essential oil were studied for the first time. GC and GC–MS analysis revealed 48 compounds representing 96.98% of the oil. Terpinen-4-ol(23.75%), meta-Cymene(17.30%), and Sabinene(12.38%)were the major constituents. Antimicrobial activity was evaluated against nine pathogens using the disc diffusion and broth micro-dilution methods. Results show that C.munbyi essential oil possesses strong antimicrobial activity against all strains, regardless if Gram-positive or Gramnegative bacteria, or yeast, with MICs values not exceeding10(mg/ml). In addition to its efficacy, C. munbyi essential oil has an unusual antimicrobial potency which is attributed to its specific chemical composition. Thus, findings presented here suggest that endemic C. munbyi contains a very interesting essential oil that may be valuable in several areas. 展开更多
关键词 Antimicrobial activity Chemical composition Cistus munbyi Essential oil
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Microbiologic risk factors of recurrent choledocholithiasis postendoscopic sphincterotomy 被引量:5
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作者 Ying Li Wen-Hui Tan +12 位作者 Jia-Chuan Wu Zhi-Xin Huang Yan-Yan Shang Biao Liang Jian-Hui Chen Rui Pang Xin-Qiang Xie Ju-Mei Zhang Yu Ding Liang Xue Mou-Tong Chen Juan Wang Qing-Ping Wu 《World Journal of Gastroenterology》 SCIE CAS 2022年第12期1257-1271,共15页
BACKGROUND Choledocholithiasis is a severe disorder that affects a significant portion of the world’s population.Treatment using endoscopic sphincterotomy(EST)has become widespread;however,recurrence post-EST is rela... BACKGROUND Choledocholithiasis is a severe disorder that affects a significant portion of the world’s population.Treatment using endoscopic sphincterotomy(EST)has become widespread;however,recurrence post-EST is relatively common.The bile microbiome has a profound influence on the recurrence of choledocholithiasis in patients after EST;however,the key pathogens and their functions in the biliary tract remain unclear.AIM To investigate the biliary microbial characteristics of patients with recurrent choledocholithiasis post-EST,using next-generation sequencing.METHODS This cohort study included 43 patients,who presented with choledocholithiasis at the Guangdong Second Provincial General Hospital between May and June 2020.The patients had undergone EST or endoscopic papillary balloon dilation and were followed up for over a year.They were divided into either the stable or recurrent groups.We collected bile samples and extracted microbial DNA for analysis through next-generation sequencing.Resulting sequences were analyzed for core microbiome and statistical differences between the diagnosis groups;they were examined using the Kyoto Encyclopedia of Genes and Genomes pathway hierarchy level using analysis of variance.Correlation between the key genera and metabolic pathways in bile,were analyzed using Pearson’s correlation test.RESULTS The results revealed distinct clustering of biliary microbiota in recurrent choledocholithiasis.Higher relative abundances(RAs)of Fusobacterium and Neisseria(56.61%±14.81%vs 3.47%±1.10%,8.95%±3.42%vs 0.69%±0.32%,respectively)and the absence of Lactobacillus were observed in the bile of patients with recurrent disease,compared to that in stable patients.Construction of a microbiological co-occurrence network revealed a mutual relationship among Fusobacterium,Neisseria,and Leptotrichia,and an antagonistic relationship among Lactobacillales,Fusobacteriales,and Clostridiales.Functional prediction of biliary microbiome revealed that the loss of transcription and metabolic abilities may lead to recurrent choledocholithiasis.Furthermore,the prediction model based on the RA of Lactobacillales in the bile was effective in identifying the risk of recurrent choledocholithiasis(P=0.03).CONCLUSION We demonstrated differences in the bile microbiome of patients with recurrent choledocholithiasis compared to that in patients with stable disease,thereby adding to the current knowledge on its microbiologic etiology. 展开更多
关键词 CHOLEDOCHOLITHIASIS Biliary tract MICROBIOME Endoscopic sphincterotomy RECURRENCE LACTOBACILLUS
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