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961.
Orchids live with mycorrhizal fungi in mutualism. This symbiotic relationship plays an essential role in the overall life cycle of orchids from germination, growth, settlement, and reproduction. Among the 1000 species of the orchid, the Korean lady’s slipper, Cypripedium japonicum, is known as an endangered species. Currently, only five natural habitats of the Korean lady’s slipper remain in South Korea, and the population of Korean lady’s slipper in their natural habitat is not increasing. To prevent extinction, this study was designed to understand the fungal community interacting in the rhizosphere of the Korean lady’s slipper living in the native and artificial habitats. In-depth analyses were performed to discover the vital mycorrhizal fungi contributing to habitat expansion and cultivation of the endangered orchid species. Our results suggested that Lycoperdon nigrescens contributed most to the increase in natural habitats and Russula violeipes as a characteristic of successful cultivation. And the fungi that helped L. nigrescens and R. violeipes to fit into the rhizosphere community in Korean lady’s slipper native place were Paraboeremia selaginellae and Metarhizium anisopliae, respectively. The findings will contribute to restoring and maintaining the endangered orchid population in natural habitats. 相似文献
962.
Shiyuan Guo Ge Wu Wenli Liu Yajuan Fan Wengang Song Jian Wu Dan Gao Xi Gu Sanhui Jing Quanquan Shen Lingyan Ren Yindi Dong Zhangsuo Liu 《Bioscience reports》2022,42(5)
Background: Morbidity of chronic kidney disease (CKD) is increased, with many complications and high mortality rates. The characteristics of oral microbiome in CKD patients have not been reported. This study aims to analyze the oral microbiome, and to demonstrate the potential of microbiome as noninvasive biomarkers for CKD patients.Methods: The study collected 253 oral samples from different regions of China (Central China and East China) prospectively and finally 235 samples completed Miseq sequencing, including 103 samples from CKD patients and 132 healthy controls (HCs).Results: Compared with HCs (n=88), the oral microbial diversity in CKD patients (n=44) was increased. Fourteen genera including Streptococcus, Actinomyces and Leptotrichia were enriched, while six genera including Prevotella and Haemophilus were decreased in CKD patients. Moreover, 49 predicted microbial gene functions including arginine metabolism and tryptophan metabolism increased, while 55 functions including Ribosome and DNA repair recombination proteins decreased. Furthermore, correlation analysis demonstrated that 38 operational taxonomic units (OTUs) were closely related to 5 clinical indicators of CKD. Notably, 7 optimal biomarkers were identified using random forest model, and the classifier model respectively reached an area under the curve (AUC) of 0.9917 and 0.8026 in the discovery and validation phase, achieving a cross-region validation.Conclusions: We first illustrated the characteristics of the oral microbiome of patients with CKD, identified the potential of oral microbial makers as noninvasive tools for the diagnosis of CKD and achieved cross-region validation. 相似文献
963.
A phage-typing scheme for Salmonella virchow 总被引:3,自引:0,他引:3
R.M. Chambers P. McAdam J.D.H. de Sa L.R. Ward B. Rowe 《FEMS microbiology letters》1987,40(2-3):155-157
964.
Demonstration of epithelium-associated microbes in the oesophagus of pigs, cattle, rats and deer 总被引:1,自引:0,他引:1
Scanning electron microscope or light microscope examination of oesphageal specimens demonstrated the association of microbial cells with the epithelial surface. Rod-shaped bacteria and cocci were seen in specimens obtained from pigs and rats, cocci in specimens from cattle, and rods 相似文献
965.
A Vibrio cholerae O1 phage-typing scheme, developed in the USSR, has been used to type 120 strains of V. cholerae O1 isolated in Africa and Asia, and 56 non-O1 V. cholerae isolated in England and Wales from infections contracted abroad. 90.9% of V. cholerae O1 were typable. Phage type 13 predominated among African strains whereas types 11 and 15 were more common among strains from Asia. Only 14.3% of non-O1 V. cholerae reacted with the phages. 相似文献
966.
Kivaandra Dayaa Rao Ramarao Chandran Somasundram Zuliana Razali Wijenthiran Kunasekaran Tan Li Jin 《Saudi Journal of Biological Sciences》2022,29(6):103290
The recent COVID-19 pandemic resulted in major postharvest losses because most fresh produce could not be sold. Drying is an important thermal-based food preservation method which could have prolonged the shelf-life of these produce, but most drying technologies are costly, and cannot be afforded by small-time farmers. From this context, we were interested in evaluating the drying of Moringa oleifera leaves (MOL) using a low-cost self-built prototype convective-air dryer (CAD), alongside conventional drying methods for its antioxidant properties, microbial load and phytoconstituents. Results showed total polyphenol content was the highest (p < 0.05) in our CAD samples, and it retained among the highest total flavonoid content, total antioxidant capacity, total alkaloid content and DPPH radical scavenging activity. Furthermore, methanolic CAD extract presented lower coliform and yeast and mold count than the aqueous CAD extract. We also briefly explored MOL as a sanitizer where the microbial load of the methanolic extract was comparable (p > 0.05) with several commercial non-alcoholic sanitizers, indicating its commercialization potential as a bio-friendly sanitizer. Finally, using GC–MS, we are the first to report (best of our knowledge) on the presence of caprolactam, an important bio-medical field compound, in the CAD sample’s aqueous extract. 相似文献
967.
金黄色葡萄球菌荚膜分型血清研制及初步应用 总被引:2,自引:0,他引:2
为了解中国金葡菌荚膜流行型,用5型和8型国际标准菌株的菌悬液免疫家兔,吸收除去交叉凝集素研制出金葡菌5型和8型荚膜分型血清,并应用于333株临床菌株荚膜分型。该血清效价为1:1280和1:640,与本菌及其它同型菌株玻片凝集反应呈强凝集,与其它型菌株不凝集,且与美国标准血清同时对333株临床分离菌株进行分型比较的符合率为100%。333株金葡地方菌株荚膜分型结果显示,8型菌株占绝对优势,所占百分率为70.9%;5型占6.3%,5型和8型菌株共占77.2%。这与国外金葡菌荚膜5型和8型占70%-80%的报道相似。试验为金葡菌疫苗株选择提供了流行病学依据。 相似文献
968.
969.
Monitoring of microbial adhesion and biofilm growth using electrochemical impedancemetry 总被引:1,自引:0,他引:1
Dheilly A Linossier I Darchen A Hadjiev D Corbel C Alonso V 《Applied microbiology and biotechnology》2008,79(1):157-164
Electrochemical impedance spectroscopy was tested to monitor the cell attachment and the biofilm proliferation in order to
identify characteristic events induced on the metal surface by Gram-negative (Pseudomonas aeruginosa PAO1) and Gram-positive (Bacillus subtilis) bacteria strains. Electrochemical impedance spectra of AISI 304 electrodes during cell attachment and initial biofilm growth
for both strains were obtained. It can be observed that the resistance increases gradually with the culture time and decreases
with the biofilm detachment. So, the applicability of electric cell-substrate impedance sensing (ECIS) for studying the attachment
and spreading of cells on a metal surface has been demonstrated. The biofilm formation was also characterized by the use of
scanning electron microscopy and confocal laser scanning microscopy and COMSTAT image analysis. The electrochemical results
roughly agree with the microscope image observations. The ECIS technique used in this study was used for continuous real-time
monitoring of the initial bacterial adhesion and the biofilm growth. It provides a simple and non-expensive electrochemical
method for in vitro assessment of the presence of biofilms on metal surfaces. 相似文献
970.
In this paper, we reported a kind of exoelectrogens, Pseudomonas alcaliphila (P. alcaliphila) strain MBR, which could excrete phenazine-1-carboxylic acid (PCA) to transfer electron under alkaline condition in microbial fuel cells (MFCs). The electrochemical activity of strain MBR and the extracellular electron transfer mechanism in MFCs were evaluated by cyclic voltammetry (CV) and electricity generation curve measurement. The results indicated a soluble mediator was the key factor for extracellular electron transfer of strain MBR under alkaline condition. The soluble mediator was PCA detected by gas chromatography-mass (GC-MS) analyses. 相似文献