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441.
Jae Kwang Kim Young Seon Kim YeJi Kim Md. Romij Uddin Yeon Bok Kim Haeng Hoon Kim Soo Yun Park Mi Young Lee Sun Ok Chung Sang Un Park 《World journal of microbiology & biotechnology》2014,30(3):887-892
Baicalin, baicalein, and wogonin were accumulated in hairy roots derived from Scutellaria lateriflora and Scutellaria baicalensis. The levels of baicalein and baicalin were 6.8 and 5.0 times higher, respectively, in S. baicalensis than in S. lateriflora. A total of 47 metabolites were detected and identified in Scutellaria species by GC-TOF MS. The metabolites from the two species were subjected to principal component analysis (PCA) to evaluate differences. PCA fully distinguished between the two species. The results showed that individual phenolic acids and phenylalanine, precursors for the phenylpropanoid biosynthetic pathway, were higher in S. baicalensis than in S. lateriflora. This GC-TOF MS-based metabolic profiling approach was a viable alternative method to differentiate metabolic profiles between species. 相似文献
442.
Bacteria isolated from spent mushroom substrate (SMS) were evaluated for the suppression of Pyricularia grisea, the causal agent of gray leaf spot of perennial ryegrass (Lolium perenne) turf. Thirty-two of 849 bacterial isolates (3.8%) from SMS significantly inhibited the mycelial growth of P. grisea in vitro. Six bacterial isolates that afforded maximum inhibition of P. grisea were also refractory to Rhizoctonia solani, Rhizoctonia cerealis, Sclerotinia homoeocarpa, and Fusarium culmorum. Each of the six isolates was identified as Pseudomonas aeruginosa by fatty acid profile analysis. The biocontrol activity of the bacterial isolates was not compromised by a prolonged exposure to UV radiation in vitro. In controlled-environment chamber experiments, all 32 bacterial isolates were tested for suppression of gray leaf spot on Pennfine perennial ryegrass when applied as seed treatment or foliar sprays. Foliar applications of the bacteria (108 cfu/ml 0.1% carboxymethylcellulose), but not the seed treatment, significantly reduced disease severity and incidence. The three most efficient isolates from foliar application treatments, which were among the six bacterial isolates identified as P. aeruginosa, were further evaluated for suppression of gray leaf spot as a function of timing of application. The three isolates of P. aeruginosa suppressed gray leaf spot in perennial ryegrass in Cone-tainers when applied at 1, 3, and 7 days prior to inoculation with P. grisea both in controlled-environment chamber experiments, and in potted ryegrass plants maintained in the field. All application intervals, regardless of the bacterial isolate, provided significant reduction of gray leaf spot severity. Suppression of gray leaf spot by isolates of P. aeruginosa under controlled-environment chamber conditions was not different from that observed in potted ryegrass plants maintained in the field. In field experiments, an isolate of P. aeruginosa provided significant suppression of gray leaf spot when applied at 1, 7, and 14 days prior to inoculation with P. grisea. The bacterium proved effective against gray leaf spot of perennial ryegrass maintained as fairway and rough heights. These results indicate that P. aeruginosa may be a potential biocontrol agent for gray leaf spot of perennial ryegrass turf. 相似文献
443.
Noor Uddin Guangqing Du Feng Chen Yu Lu Qing Yang Hao Bian Jiale Yong Xun Hou 《Plasmonics (Norwell, Mass.)》2017,12(3):627-630
Plasmonic optical trapping is widely applied in the field of bioscience, microfluidics, and quantum optics. It can play a vital role to extend optical manipulation tools from micrometer to nanometer scale level. Currently, it is a challenge to obtain the highly stable optical trapping with low power and less damage. In this paper, we propose Fano resonance-assisted self-induced back-action (FASIBA) method, through which a single 40-nm gold particle can be trapped in hole-slit nano-aperture milled on metallic film. It is used to achieve ultra-accurate positioning of nanoparticle, metallic nanostructures at wide infrared wavelength range, quite effectively and evidently. The stable plasmonic trapping is achieved by tuning the transmission wavelengths and modifications of nanoslit, indicating that the depth of potential well can be increased from minus 8KT to 12KT, with the input power of 109 W/m2. This can be attributed to great modifications in Fano resonance transmissions according to self-induced back-action (SIBA) theory. The results are basically helpful to facilitate the trapping with lower power and less damage to the objects, which enables new scenario for the treatment of undesirable spread of a single nanoscale creature, such as virus. 相似文献
444.
Md. Nizam Uddin Md. Zinnatul Alam Md. Ramiz Uddin Miah Md. Ismail Hossain Mian Kishowar‐E‐ Mustarin 《Entomological Research》2017,47(2):84-93
The life table of the indigenous Neoseiulus californicus was studied at different temperatures and 65 ± 5% relative humidity under conditions of 16 h light : 8 h dark (LD 16:8). The total developmental period from egg to adult varied from 3.0 to 14.0 days at 15 to 35°C. Survival to adulthood ranges from 86.21 to 93.94%, with the highest rate at 25°C. The lower threshold temperature from egg to adult stages of females and males was 10.84 and 10.72°C, respectively, and the thermal constant was 57.14 degree‐days (DD) for females and 56.18 DD for males. Total number of eggs laid by each female was the highest (70.38 eggs) at 25°C, whereas average daily fecundity was the highest (3.69 eggs/female/day) at 30°C. The net reproductive rate was the highest (48.49) at 25°C and lowest (26.18) at 30°C. Mean generation time decreased from 19.04 to 11.47 days with increasing temperature from 20 to 30°C. Both intrinsic rate of natural increase (0.284) and finite rate of increase (1.32) were maximum at 30°C. Adult longevity was the highest (42.75 days for females and 32.60 days for males) at 20°C and lowest (22.70 days for females and 15.30 days for males) at 30°C. Sex ratio was female biased and was the highest (78.08) at 25°C and lowest (70.24) at 30°C. Developmental data of five constant temperatures, temperature thresholds and thermal requirements may be used to predict the occurrence, number of generations and population dynamics of N. californicus as an important biocontrol agent of Tetranychus urticae. 相似文献
445.
Codon usage bias refers to the differences in the occurrence frequency of synonymous codons. To understand the patterns of codon usage in mitochondrial genes we used bioinformatic approaches to analyze the protein coding sequences of W. bancrofti and S. haematobium as no work was reported earlier. It was found that the ENC value ranged from 43 to 60 with a mean of 46.91 in W. bancrofti but varied from 49 to 60 with a mean of 45.17 in S. haematobium, respectively. In W. bancrofti a significant positive correlation was found between ENC and GC3% (r = 0.826**, p < 0.01), but in S. haematobium significant correlation was found between ENC and GC3% (r = 0.983**, p < 0.01). Principal component analysis suggests that the pattern of codon usage significantly differed between W. bancrofti and S. haematobium. Neutrality plot reveals that natural selection played a major role while mutation pressure played a minor role in codon usage pattern in the mitochondrial protein coding genes of W. bancrofti and S. haematobium. Various factors namely nucleotide composition, natural selection and mutation pressure affected the codon usage pattern. 相似文献
446.
Water availability moderates N2 fixation benefit from elevated [CO2]: A 2‐year free‐air CO2 enrichment study on lentil (Lens culinaris MEDIK.) in a water limited agroecosystem
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Shahnaj Parvin Shihab Uddin Maryse Bourgault Ute Roessner Sabine Tausz‐Posch Roger Armstrong Garry O'Leary Glenn Fitzgerald Michael Tausz 《Plant, cell & environment》2018,41(10):2418-2434
Increased biomass and yield of plants grown under elevated [CO2] often corresponds to decreased grain N concentration ([N]), diminishing nutritional quality of crops. Legumes through their symbiotic N2 fixation may be better able to maintain biomass [N] and grain [N] under elevated [CO2], provided N2 fixation is stimulated by elevated [CO2] in line with growth and yield. In Mediterranean‐type agroecosystems, N2 fixation may be impaired by drought, and it is unclear whether elevated [CO2] stimulation of N2 fixation can overcome this impact in dry years. To address this question, we grew lentil under two [CO2] (ambient ~400 ppm and elevated ~550 ppm) levels in a free‐air CO2 enrichment facility over two growing seasons sharply contrasting in rainfall. Elevated [CO2] stimulated N2 fixation through greater nodule number (+27%), mass (+18%), and specific fixation activity (+17%), and this stimulation was greater in the high than in the low rainfall/dry season. Elevated [CO2] depressed grain [N] (?4%) in the dry season. In contrast, grain [N] increased (+3%) in the high rainfall season under elevated [CO2], as a consequence of greater post‐flowering N2 fixation. Our results suggest that the benefit for N2 fixation from elevated [CO2] is high as long as there is enough soil water to continue N2 fixation during grain filling. 相似文献
447.
The direct attachment and growth of gold or silver nanoparticles (NPs) on indium tin oxide (ITO) surfaces was demonstrated using a simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method by chemical reduction of the precursor metal salts with dopamine aqueous solution. Ag NPs on ITO substrate were approximately spherical with an average particle size of about 57 nm, but had a wide particle size distribution. Compared with Ag NPs, under the same 10 SILAR cycles, Au NPs have higher density packing and smaller average particle size of about 36 nm. XRD characterization and surface chemistry analysis confirmed the formation of Ag and Au NPs on ITO substrate with small amounts of dopamine-quinone adsorbed on the surface of them. Although Au NPs showed characteristic plasmon absorption, this did not result in performance enhancement in solar cell with the structure of ITO/ZnO/PCPDTBT:[6,6]-phenyl C71/MoO3/Ag because of the energy level mismatch between ZnO and dopamine molecules adsorbed on the surface of metal NPs. 相似文献
448.
449.
Guo H Zhou J Jing W Zhang X Zhang Z Uddin MS 《Bioprocess and biosystems engineering》2005,27(4):249-254
A novel combined biofilm reactor was established and applied as a single treatment unit for carbon and nitrogen removal of
wastewater. The nitrogen removal performance of the reactor at different levels of organic carbon (COD) loading was investigated
when the influent total nitrogen (TN) loading was 0.74 g TN/m2 day. Continuous experimental results demonstrated that 80% nitrogen was eliminated when the influent COD loading ranged between
2.06 g and 3.92 g COD/m2 day. Microbial composition in the reactor was analyzed using fluorescent in situ hybridization (FISH) and conventional batch
tests. The relative abundance of ammonia-oxidizing bacteria in the aerobic zone of the reactor measured by FISH was consistent
with the result from conventional batch tests. 相似文献
450.
Ahmed Salahuddin Kabir Daizy Bharti Santosh Kumar Shahed Uddin Ahmed Shazib Mann Kyoon Shin 《The Journal of eukaryotic microbiology》2020,67(5):541-554
The morphology and morphogenesis of Rigidohymena inquieta (Stokes, 1887) Berger, 2011, isolated from a lawn soil in the campus of the University of Ulsan, Korea, was studied, using live observation and protargol impregnation. The molecular phylogeny was studied based on the SSU rRNA gene sequences. The morphology of the Korean population of R. inquieta matches the previously known populations; however, the morphogenetic pattern shows differences to the species R. candens in the involvement of cirrus V/3 in the anlagen formation. A novel genus namely Metahymena gen. nov. has been erected for the present species based on the ontogenetic difference, and the new combination Metahymena inquieta gen. nov., comb. nov. is proposed. The morphology, morphogenesis, distribution, and phylogeny of M. inquieta are presented. The morphologic and morphogenetic data corroborate the phylogenetic analyses as M. inquieta clusters among the stylonychid ciliates in a clade distant from Rigidohymena candens. 相似文献