ion cyclotron resonance
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2022 ◽  
Author(s):  
Konstantin V. Moiseenko ◽  
Olga S. Savinova ◽  
Olga A. Glazunova ◽  
Arkadiy P. Sinitsyn ◽  
Tatiana V. Fedorova

Trameteshirsuta is a wood rotting fungus that possesses a vast array of lignin degrading enzymes, including7 laccases, 7 ligninolyticmanganese peroxidases, 9 lignin peroxidases and 2 versatile peroxidases. In this study,electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS)was used to examine kraft lignin modification by the enzymatic system of this fungus.The observed pattern of lignin modification suggested that before the 6th day of cultivation,the fungal enzymatic system tended to degrade more oxidized moleculesand, hence, less recalcitrant molecules, with the production of hard-to-modify reduced molecular species. At some point after the 6th day of cultivation,the fungal enzymatic system tended to degrade more oxidized moleculesand, hence, less recalcitrant molecules, with the production of hard-to-modify reduced molecular species. At some point after the 6th day of cultivation,the fungus started to degrade less oxidized, more recalcitrant, compounds, converting them into the more oxidized forms. The altered pattern of lignin modification enabled changes in the fungal enzymatic system. These changes were further attributed to the appearance of the particular ligninolyticmanganese peroxides enzyme(MnP7), which was added by the fungus to the mixture of enzymes that had already been secreted (VP2 and MnP5). Keywords: wood rotting fungi, kraft lignin, mass spectrometry, peroxidases


2022 ◽  
Author(s):  
Hongxing Jiang ◽  
Jun Li ◽  
Jiao Tang ◽  
Min Cui ◽  
Shizhen Zhao ◽  
...  

Abstract. Organosulfur compounds (OrgSs), especially organosulfates, have been widely reported at large quantities in particulate organic matter found in various atmospheric environments. Despite various kinds of organosulfates and their formation mechanisms being previously identified, a large fraction of OrgSs remain unexplained at the molecular level, impeding further knowledge on additional formation pathways and critical environmental parameters that help to explain their concentrations. In this work, the abundance and molecular composition of OrgSs in fine particulate samples collected in Guangzhou was reported. Our results revealed that organic sulfur can averagely contribute to 30 % of total particulate sulfur, and showed positively correlations with the SO2 (r = 0.37, p < 0.05) and oxidants (NOx+O3, r = 0.40, p < 0.01). Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) results presented that more than 80 % by number of the detected OrgSs in our samples have the elemental composition of O/(4S+3N)  ≥ 1, indicating that they were largely in the form of oxidized organosulfates and/or nitrooxy organosulfates. Many OrgSs, which are tentatively attributed to previously identified biogenic and anthropogenic origins, were also present in aerosols derived from freshly-emitted combustion sources. Results show that the formation of OrgSs through an epoxide intermediate pathway could be as much as 46 %, and the oxidants levels could explain 20 % variation of organic sulfur mass. The analysis from our large FT-ICR MS dataset suggests that relative humidity, oxidation of biogenic volatile organic compounds via ozonolysis, and NOx-related nitrooxy organosulfate formations were the major reasons for the molecular variation of OrgSs, possibly highlighting the importance of heterogeneous reactions involving either the uptake of SO2 or the heterogeneous oxidations of particulate organosulfates into additional unrecognized OrgSs.


2021 ◽  
Vol 11 (40) ◽  
pp. 149-149
Author(s):  
Settimio Grimaldi

Background: Only recently has the critical importance of electromagnetic (EM) field interactions in biology and medicine been recognized. We review the phenomenon of resonance signaling, discussing how specific frequencies modulate cellular function to restore or maintain health. Evidence: Application of EM tuned signals represents more than merely a new tool in Information Medicine. It can also be viewed in the larger context of Electromagnetic Medicine, the all-encompassing view that elevates the electromagnetic over the biochemical. The discovery by Zhadin that ultrasmall magnetic intensities are biologically significant suggests that EM signaling is endogenous to cell regulation, and consequently that the remarkable effectiveness of EM resonance treatments reflects a fundamental aspect of biological systems. The concept that organisms contain mechanisms for generating biologically useful electric signals is not new, dating back to the 19th century discovery of currents of injury by Matteucci. The corresponding modern-day version is that ion cyclotron resonance magnetic field combinations help regulate biological information. Prospects: The next advance in medicine will be to discern and apply those electromagnetic signaling parameters acting to promote wellness, with decreasing reliance on marginal biochemical remediation and pharmaceuticals.


Separations ◽  
2021 ◽  
Vol 8 (12) ◽  
pp. 245
Author(s):  
Filomena Lelario ◽  
Raffaella Pascale ◽  
Giuliana Bianco ◽  
Laura Scrano ◽  
Sabino Aurelio Bufo

The development and application of advanced analytical methods for a comprehensive analysis of Cannabis sativa L. extracts plays a pivotal role in order to have a reliable evaluation of their chemotype definition to guarantee the efficacy and safety in pharmaceutical use. This paper deals with the qualitative and quantitative determination of cannabidiol (CBD), tetrahydrocannabinol (THC), cannabinol (CBN), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), and cannabigerol (CBG) based on a liquid chromategraphy-mass spectrometry (LC-MS) method using electrospray ionization in positive mode (ESI+), coupled with a hybrid quadrupole linear ion trap (LTQ) and Fourier transform ion cyclotron resonance mass spectrometer (FTICR-MS). For the first time, structural information of phytocannabinoids is available upon precursor ions’ isolation within the FTICR trapping cell and subsequent fragmentation induced by infrared multiphoton dissociation (IRMPD). Such fragmentation and accurate mass measurement of product ions, alongside collision-induced dissociation (CID) within LTQ, was advantageous to propose a reliable fragmentation pattern for each compound. Then, the proposed LC-ESI(+)-LTQ-FTICR MS method was successfully applied to the hemp chemotype definition of three registered Italian accessions of hemp C. sativa plants (Carmagnola C.S., Carmagnola, and Eletta Campana), thus resulting in the Eletta Campana accession being the best one for cannabis product manufacturing.


Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3553
Author(s):  
Anna N. Khreptugova ◽  
Tatiana A. Mikhnevich ◽  
Alexandra A. Molodykh ◽  
Sofia V. Melnikova ◽  
Andrey I. Konstantinov ◽  
...  

Large scale isolation—in gram quantities—of dissolved organic matter (DOM) from natural waters is necessary for detailed investigation of its role in chemical and microbial processes driving carbon cycling under conditions of global climate change. The best candidate for a use in these large-scale experiments is a bulk sorbent Bondesil PPL, which has the same modification as the widely used Bond Elut PPL sorbent. There have been no studies so far reported on interchangeability of these sorbents with regard to DOM isolation. This work was devoted to comparative studies on sorption efficiency and molecular selectivity of these two sorbents—Bond Elut PPL and Bondesil PPL with regard to DOM components. Fulvic acids (FA) from peat water leachate were used as a model DOM. Laboratory solid phase extraction (SPE) setup was used for monitoring sorption recovery and extraction yield. It included three parallel experiments on pre-packed Bond Elut PPL cartridges (500 mg/3 mL) and three self-packed Bondesil PPL cartridges (500 mg/3 mL). Fourier transform ion cyclotron resonance mass spectrometry (FT ICR MS) and 13C/1H nuclear magnetic resonance (NMR) spectroscopy were used for determination of molecular and structural group compositions of the FA isolates obtained with a use of two different sorbents. The results of this study allowed a conclusion on interchangeability of the two sorbents used in this study for the purposes of DOM isolation from natural waters. This conclusion was backed up by similarity of sorption behavior of the peat FA components on both sorbents and by high similarity of molecular compositions and carbon distribution among the main structural groups.


Metabolites ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 843
Author(s):  
Kevin J. Zemaitis ◽  
Heng Ye ◽  
Henry T. Nguyen ◽  
Troy D. Wood

Drought is the most prolific form of abiotic stress that legumes and cereal plants alike can endure, and the planting of an improper cultivar at the beginning of a season can cause unexpected losses up to fifty percent under water deficient conditions. Herein, a plant introduction (PI) of an exotic cultivar of soybean (Glycine max), PI 567731, which demonstrates a slow wilting (SW) canopy phenotype in maturity group III, was profiled under drought conditions in field trials in Missouri against a drought susceptible check cultivar, Pana. Metabolomic profiling was carried out on samples of leaves from each of these cultivars at V5 and R2 growth stages both while irrigated and while under drought stress for three weeks. PI 567731 was observed to have differential phytochemical content, and enhanced levels of chlorophyll (Chl) a/b and pheophytin (Pheo) were profiled by direct infusion electrospray Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Indicating drought induced changes of the photosystem and photosynthetic capabilities alongside water preservation strategies are important within the SW phenotype drought response. Subsequent multivariate analysis was able to form predictive models, encompassing the variance of growth and drought stress of the cultivar. Moreover, the existence of unique Chl-related metabolites (CRM) (m/z > 900) were confirmed through tandem mass spectrometry. The resultant coordination of fatty acids to the core of the porphyrin ring was observed and played an unknown role in the proliferation of the photosynthesis. However, the relative ratio of the most abundant CRM is undisturbed by drought stress in PI 567731, in contrast to the drought susceptible cultivar. These results provide key insights into drought related metabolic mechanisms.


2021 ◽  
Vol 87 (6) ◽  
Author(s):  
V. Maquet ◽  
A. Druart ◽  
A. Messiaen

In the ion cyclotron range of frequency (ICRF), the presence of a lower hybrid (LH) resonance can appear in the edge of a tokamak plasma and lead to deleterious edge power depositions. An analytic formula for these losses is derived in the cold plasma approximation and for a slab geometry using an asymptotic approach and an analytical continuation near the LH resonance. The way to minimize these losses in a large machine like ITER is discussed. An internal verification between the power loss computed with the semi-analytical code ANTITER IV for ion cyclotron resonance heating (ICRH) and the analytic result is performed. This allows us to check the precision of the numerical integration of the singular set of cold plasma wave differential equations. The set of cold plasma equations used is general and can be applied in other parameters domain.


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