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1.
PLoS One ; 19(3): e0299861, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38502649

RESUMO

The challenge facing Ethiopian farmers are the combination of low soil fertility and reduced agricultural productivity. The study aimed to quantify nitrogen and phosphorus-containing fertilizers for tef production in Sekota and Lasta-Lalibela districts, using four nitrogen and three phosphorus levels from urea and triple super phosphate sources. The Results showed that nitrogen and phosphorus fertilizers significantly affected tef yield and yield components. Application of nitrogen at the rate of 92 kg ha-1 increased tef grain yield by 131.01%, 87.78% and 182.23% in Woleh, Sayda and Lasta Lalibela districts, respectively, compared to control treatment. Similarly, 23 kg ha-1 phosphorus increased tef grain yield by 7.42 and 8.52% in Woleh and Lasta Lalibela, respectively. In Lalibela and Woleh, the application of 92 kg N ha-1 resulted in a maximum net benefits of 2099.6 and 2007 United States Dollar (USD) respectively. Furthermore, in Sayda, the application of 92 kg N ha-1 and 23 kg P2O5 ha-1 yielded a net benefit of 1812.55 USD. The marginal rate of return (MRR) from these applications was 539.6% in Lalibela, 781% in Woleh and 352.44% in Sayda. Therefore, application of 92 N and 23 kg P2O5 ha-1 is appropriate for maximum tef production in Sekota and Lasta districts of Amhara region. Further research and extension services should focus on promoting the adoption of these optimized fertilizer practices among smallholder farmers to maximize the sustainable production of tef.


Assuntos
Fertilizantes , Compostos de Fósforo , Fósforo , Nitrogênio/análise , Etiópia , Agricultura/métodos , Solo , Grão Comestível/química
2.
Chempluschem ; 88(6): e202300176, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37222183

RESUMO

PCl3 and POCl3 are the most important sources of phosphorus-containing compounds. They are also used for large-scale industrial productions. However, chemical reactions using the highly reactive PCl3 and POCl3 tend to result in overreactions. In addition, the reactions are usually exothermic and therefore their utilization sometimes involves significant risk. That is why some phosphorylating reagents with mild electrophilicity such as phosphoramidites have been developed. Although these mild electrophiles are very useful for the highly selective synthesis of organophosphorus compounds, problems persist: the high cost of the reagents, the generation of large amounts of waste, and the requirement of long reaction times and high temperatures. Continuous-flow technology is one of the most promising solutions for these problems. In particular, precise control of reaction times and temperatures enabled by micro-flow technology suppresses undesired reactions and allows the safe operation of exothermic reactions using highly reactive PCl3 and POCl3 . This Review describes recently reported reactions of PCl3 and POCl3 using continuous- and micro-flow technologies.


Assuntos
Compostos de Fósforo , Compostos de Fósforo/química , Temperatura
3.
Artigo em Inglês | MEDLINE | ID: mdl-36669121

RESUMO

To estimate the daily intake of food additives by young children aged 1-6 years in Japan, an intake survey was conducted in 2018 using the market basket method for food additives, including twelve types of colourants, three kinds of preservatives, three kinds of sweeteners and two kinds of food manufacturing agents. A list of the daily consumption of processed foods was prepared based on a special survey (MHLW 2011) and used for the estimation. The results of the survey showed that the food additives with the highest daily intake were phosphorus compounds (phosphoric acid and its salts; 11.2 mg/kg bw/day, expressed as phosphorus), followed by propylene glycol (0.80 mg/kg bw/day). The daily intake of other food additives ranged from 0 to 0.20 mg/kg bw/day. The estimated daily intake of each food additives by young children was compared with the acceptable daily intake (ADI) or maximum tolerable daily intake (MTDI). The highest ratio of the estimated daily intake to ADI was 3.2% for propylene glycol, whereas the ratios of the estimated daily intake to ADI for colourants, preservatives and sweeteners ranged from 0 to 1.1% (benzoic acid). The ratio of the estimated daily intake to MTDI for phosphorus compounds was 16%.


Assuntos
Dieta , População do Leste Asiático , Aditivos Alimentares , Criança , Pré-Escolar , Humanos , Propilenoglicol , Edulcorantes , Lactente , Compostos de Fósforo
4.
Eur Endod J ; 8(4): 253-261, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38219032

RESUMO

OBJECTIVE: The primary objective of this randomised clinical trial was to evaluate the efficacy of Calcium Enriched Mixture (CEM) cement compared to Mineral Trioxide Aggregate (MTA) and Calcium Hydroxide (CH) in maintaining pulp vitality when used for direct pulp capping (DPC) of deep carious lesions with reversible pulpitis and secondary objective was to assess the overall success of DPC in carious exposures. METHODS: One hundred and fifty patients diagnosed with reversible pulpitis with deep carious lesions were included in this study. Patients were randomly allocated into three groups (n=50), Group C: CEM group, Group M: MTA group, and Group D: CH (Dycal) group. After caries removal by mechanical excavation except for one carious spot, the removal of which resulted in the exposure of the pulp, the final carious spot was removed with a sterile no.2 round carbide bur. After haemostasis, the pulpal wound was dressed by a capping agent, followed immediately by permanent restoration. Patients were assessed for successful outcomes based on positive vitality tests, absence of clinical signs and symptoms, and PAI scores after 1, 3, 6, 12, and 18-month follow-up periods. The ANOVA test was employed to analyse quantitative variables, and the Pearson Chi-square test was used for qualitative variables. A Bonferroni Test was employed as the post hoc test for intergroup comparison. The significance level was set at p≤0.05 within all tests. RESULTS: The percentage of success in Group C was 86.7%, Group M was 77.3%, and Group D was 57.9%. This study's overall success rate after direct pulp capping of deep carious lesions was 74.8%. A statistically significant difference in PAI score was found between Groups C and D. Pain on percussion and response to vitality tests also showed significant differences among the three groups at the one-month follow-up. CONCLUSION: CEM cement had comparable efficacy to MTA and was superior to CH in maintaining pulpal vitality following DPC in teeth with reversible pulpitis. An overall success rate of 74.8% indicated that DPC in deep carious lesions with reversible pulpitis could yield favourable clinical outcomes. (EEJ-2022-11-134).


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Cárie Dentária , Óxidos , Compostos de Fósforo , Agentes de Capeamento da Polpa Dentária e Pulpectomia , Pulpite , Silicatos , Humanos , Hidróxido de Cálcio/uso terapêutico , Agentes de Capeamento da Polpa Dentária e Pulpectomia/uso terapêutico , Cálcio , Pulpite/tratamento farmacológico , Capeamento da Polpa Dentária/métodos , Cárie Dentária/terapia , Cárie Dentária/complicações , Combinação de Medicamentos
5.
Inorg Chem ; 61(49): 19925-19932, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36453123

RESUMO

Herein, we present a simple synthesis of mixed-valent phosphinophosphoranes bearing three- and five-coordinate phosphorus centers. Compounds with phosphorus-phosphorus bonds were synthesized via a reaction of lithium phosphides RR'PLi with cat2PCl (cat = catecholate), whereas derivatives with methylene-linked phosphorus centers were obtained via a reaction of phosphanylmethanides RR'CH2Li with cat2PCl. The presence of accessible lone-pair electrons on the P-phosphanyl atom of phosphinophosphoranes during the reaction of the title compounds with H3B·SMe2, where phosphinophosphorane-borane adducts were formed quantitatively, was confirmed. Furthermore, the Lewis basic and Lewis acidic properties of the phosphinophosphoranes in reactions with phenyl isothiocyanate were tested. Depending on the structure of the starting phosphinophosphorane, phosphinophosphorylation of PhNCS or formation of a five-membered zwitterionic adduct was observed. The structures of the isolated compounds were unambiguously determined by heteronuclear nuclear magnetic resonance spectroscopy and single-crystal X-ray diffraction. Moreover, by applying density functional theory calculations, we compared the Lewis basicity and nucleophilicity of diversified trivalent P-centers.


Assuntos
Compostos de Fósforo , Cristalografia por Raios X , Fósforo/química , Elétrons , Espectroscopia de Ressonância Magnética , Lítio
6.
J Environ Manage ; 322: 116031, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055093

RESUMO

Slash and burn is a land use practice widespread all over the world, and nowadays it is formally recognized as the principal livelihood system in rural areas of South America, Asia, and Africa. The practice consists of a land rotation where users cut native or secondary forest to establish a new crop field and, in some cases, build charcoal kilns with the cut wood to produce charcoal. Due to several socio-economic changes in developing countries, some scientists and international organizations have questioned the sustainability of slash and burn since in some cases, crop yield does not justify the soil degradation caused. To estimate the soil quality in agricultural and forest soils at different ages of the forest-fallow period (25, 35, and 50 years), this survey investigated rural areas in three locations in Manica province, central Mozambique: Vanduzi, Sussundenga, and Macate. Soil profiles were trenched and sampled with a pedological approach under crop fields and forest-fallow. The chronosequence was selected to test the hypothesis that the increase in forest-fallow age causes an improvement of soil fertility. Results highlighted discrete variations among locations in mineralogy, Al- and Fe-oxyhydroxides, sand, silt, pH, total organic carbon, humic carbon, total nitrogen, available phosphorous, chloride, nitrate, fluoride, and ammonium. Few differences in mineralogy, Fe-oxyhydroxides, available P, chloride, and nitrate were detected between crop fields and forest-fallow within the same location. Such differences were mostly ascribed to intrinsic fertility inherited from the parent material rather than a longer forest-fallow period. However, physicochemical soil property improvement did not occur under a forest age of 50 years (the longest forest-fallow considered), indicating that harmonization of intrinsic fertility and agronomic practices may increase soil organic matter and nutrient contents more than a long forest-fallow period.


Assuntos
Compostos de Amônio , Queimaduras , Agricultura/métodos , Carbono , Carvão Vegetal , Cloretos , Fluoretos , Humanos , Pessoa de Meia-Idade , Moçambique , Nitratos , Nitrogênio , Compostos de Fósforo , Areia , Solo/química
7.
J Med Chem ; 65(12): 8511-8524, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35678759

RESUMO

Systematically studying the lipophilicity of phosphorus compounds is of great importance for many chemical and biological fields and particularly for medicinal chemistry. Here, we report on the study of trends in the lipophilicity of a wide set of phosphorus compounds relevant to drug design including phosphates, thiophosphates, phosphonates, thiophosphonates, bis-phosphonates, and phosphine chalcogenides. This was enabled by the development of a straightforward log P determination method for phosphorus compounds based on 31P-NMR spectroscopy. The log P values measured ranged between -3.2 and 3.6, and the trends observed were interpreted using a DFT study of the dipole moments and by H-bond basicity (pKHB) measurements of selected compounds. Clear signal separation in 31P-NMR spectroscopy grants the method high tolerability to impurities. Moreover, the wide range of chemical shifts for the phosphorus nucleus (250 to -250 ppm) enables a direct simultaneous log P determination of phosphorus compound mixtures in a single shake-flask experiment and 31P-NMR analysis.


Assuntos
Organofosfonatos , Compostos de Fósforo , Espectroscopia de Ressonância Magnética/métodos , Fósforo/química
8.
Science ; 376(6598): 1157-1158, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679417
9.
Angew Chem Int Ed Engl ; 61(30): e202202467, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35548922

RESUMO

Axially chiral biaryl monophosphorus molecules, exemplified by atropisomeric 1,1'-biaryl aminophosphines, are significant motifs in numerous chiral ligands/catalysts. Developing efficient methods for preparing phosphorus compounds with these privileged motifs is an important endeavor in synthetic chemistry. Herein, we develop an effective, modular method by a chiral-phosphonium-salt-catalyzed novel cascade between phosphorus-containing nitroolefins and α,α-dicyanoolefins, leading to a great diversity of atropisomeric biaryls bearing phosphorus groups in high yields with excellent stereoselectivities. The reaction features include a Thorpe-type cycloaddition/oxidative hydroxylation/aromatization cascade pathway with a central-to-axial chirality transfer process. Insight gained from our studies is expected to advance general efforts towards the catalytic synthesis of atropisomeric biaryl phosphorus compounds, offering a platform for developing new efficient chiral ligands and catalysts.


Assuntos
Compostos de Fósforo , Fenômenos Químicos , Ligantes , Fósforo , Estereoisomerismo
10.
Chemistry ; 28(37): e202200932, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35481688

RESUMO

We demonstrate a sequential nucleophilic substitution of highly electrophilic and inexpensive phosphorus trichloride with three different alcohols in a continuous-flow reactor. A variety of alcohols including ones that contained acid- and/or basic-labile functionalities were rapidly reacted. A over nucleophilic substitution that occurred during reaction of the second alcohol was suppressed by the addition of imidazole. Density functional theory calculations of the sequential nucleophilic substitutions of alcohols were performed both with and without imidazole, and Berry pseudorotation was suggested as a rate-limiting step in both cases. Herein, we discuss the reasons for the decreased selectivity in the absence of imidazole as well as those for improved selectivity in the presence of imidazole during the second nucleophilic substitution.


Assuntos
Álcoois , Compostos de Fósforo , Cloretos , Imidazóis
11.
Anal Bioanal Chem ; 414(2): 1129-1139, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34719746

RESUMO

A label-free electrochemical immunosensor has advantages of real-time and rapid detection, but it is weak in detection of small molecular toxins such as aflatoxin B1 (AFB1). The greatest obstacle to achieving this is that small molecules bound to a common immunosensing interface cannot interfere with electron transfer effectively and the detection signal is so weak. Therefore, a sensitive electrochemical immunosensing interface for small molecules is urgently needed. Here, we employed functionalized black phosphorene (BP) as electrode modification materials and anti-AFB1 nanobody (Nb) as a biorecognition element to construct a very sensitive immunosensing interface towards small molecular AFB1. The BP functionalized by carboxylic multi-walled carbon nanotubes (MWCNTs-COOH) via P-C bonding behaved with a satisfactory stability and good catalytic performance for the ferricyanide/ferrocyanide probe, while the small-sized Nb showed good compatibility with the functionalized BP and also had less influence on electron transfer than monoclonal antibody (mAb). Expectedly, the as-prepared immunosensing interface was very sensitive to AFB1 detection by differential pulse voltammetry (DPV) in a redox probe system. Under optimized conditions, a linear range from 1.0 pM to 5.0 nM and an ultralow detection limit of 0.27 pM were obtained. Additionally, the fabricated immunosensor exhibited satisfactory stability, specificity, and reproducibility. The strategy proposed here provides a more reliable reference for label-free sensing of small molecules in food samples.


Assuntos
Aflatoxina B1/análise , Técnicas Eletroquímicas/métodos , Compostos de Fósforo/química , Anticorpos de Domínio Único/química , Técnicas Biossensoriais/métodos , Limite de Detecção
12.
Biomater Sci ; 9(23): 7876-7894, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34676835

RESUMO

Bioactive glasses (BGs) are attractive materials for bone tissue engineering because of their bioactivity and osteoinductivity. In this study, we report the synthesis of a novel phosphorous pentoxide-free, silicate-based bioactive glass (52S-BG) composed of 52.1% SiO2, 23.2% Na2O and 22.6% CaO (wt%). The glass was thoroughly characterized. The biocompatibility and osteogenic properties of 52S-BG particles were analyzed in vitro with human adipose-derived mesenchymal stem cells (AdMSCs) and human osteoblasts. 52S-BG particles were biocompatible and induced mineralized matrix deposition and the expression of osteogenic markers (RunX2, alkaline phosphatase, osteocalcin, osteopontin, collagen I) and the angiogenic marker vascular endothelial growth factor (VEGF). Angiogenic properties were additionally confirmed in a zebrafish embryo model. 52S-BG was added to poly-ε-caprolactone (PCL) to obtain a composite with 10 wt% glass content. Composite PCL/52S-BG scaffolds were fabricated by additive manufacturing and displayed high porosity (76%) and pore interconnectivity. The incorporation of 52S-BG particles increased the Young's modulus of PCL scaffolds from 180 to 230 MPa. AdMSC seeding efficiency and proliferation were higher in PCL/52S-BG compared to PCL scaffolds, indicating improved biocompatibility. Finally, 52S-BG incorporation improved the scaffolds' osteogenic and angiogenic properties by increasing mineral deposition and inducing relevant gene expression and VEGF protein secretion. Overall, 52S-BG particles and PCL/52S-BG composites may be attractive for diverse bone engineering applications requiring concomitant angiogenic properties.


Assuntos
Materiais Biocompatíveis , Peixe-Zebra , Indutores da Angiogênese , Animais , Vidro , Humanos , Osteogênese , Compostos de Fósforo , Dióxido de Silício , Fator A de Crescimento do Endotélio Vascular
13.
Gen Dent ; 69(6): 58-61, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34678745

RESUMO

This study aimed to assess the thermal effect of different light irradiation times on the setting time of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cements. This in vitro experimental study evaluated 40 hydraulic cement specimens, including 20 MTA and 20 CEM specimens, according to the manufacturers'instructions. For each cement, the specimens were divided into 3 test groups light cured with a halogen light-curing unit (n = 5 per group) and 1 control group (n = 5) that was not exposed to irradiation. The specimens in the MTA test groups were light cured for 20, 40, or 60 seconds, and the specimens in the CEM test groups were light cured for 60, 90, or 120 seconds. All test and control groups had 60 seconds of rest time. Setting of the cements was assessed at different timepoints using a Gillmore needle weighing 113.4 g with a 12.2-mm diameter according to ASTM C266-03 standards. The data were analyzed with the Fisher exact test and the Mann-Whitney U test (α = 0.05). The setting of MTA specimens after different curing times was significantly different (P < 0.05). The setting time of MTA control specimens was significantly longer than that of test specimens (P = 0.008). The setting of CEM specimens after different curing times was not significantly different (P > 0.05). However, the setting time for CEM control specimens was significantly longer than that for test specimens (P = 0.008). Light curing with a halogen light-curing unit can significantly decrease the setting time for MTA and CEM cements.


Assuntos
Compostos de Cálcio , Cimentos Dentários , Silicatos , Compostos de Alumínio , Cimentos Dentários/efeitos da radiação , Combinação de Medicamentos , Óxidos , Compostos de Fósforo
14.
Nutrients ; 13(8)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34445034

RESUMO

In 2012, the Japanese Society for Dialysis Therapy (JSDT) established the order of correction of P, corrected Ca (cCa), and whole PTH (w-PTH) in the treatment of Chronic Kidney Disease-Metabolic Bone Disorder (CKD-MBD) as P-first. However, there is no report that analyzes whether this rule is in line with reality and what the adequate rate of P is. Therefore, we analyzed the test values of our 48 patients during the year of 2019 and examined the validity of the results. The results showed that the adequate range rates were 70.8% for P, 100% for cCa, and 89.6% for w-PTH. This result is better than the JSDT Web-based Analysis of Dialysis Data Archives (WADDA) P adequacy rate of 66.2%. Although the guideline is P-first, it is often the case that we cannot reach the adequate level; therefore, healthcare professionals and patients often blame each other. We believe that this is due to the mismatch between the modern era of processed foods covered with P additives and treatment methods (P intake restriction and P-binders). The development of processed foods with P additives has brought light and darkness to mankind. The light side is freedom from starvation, and the dark side is a new condition caused by P burden: P burden disease including CKD-MBD.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/etiologia , Aditivos Alimentares/efeitos adversos , Manipulação de Alimentos , Compostos de Fósforo/efeitos adversos , Fósforo na Dieta/efeitos adversos , Biomarcadores/sangue , Calcimiméticos/uso terapêutico , Cálcio/sangue , Quelantes/uso terapêutico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/sangue , Distúrbio Mineral e Ósseo na Doença Renal Crônica/diagnóstico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/terapia , Fator de Crescimento de Fibroblastos 23 , Humanos , Hormônio Paratireóideo/sangue , Compostos de Fósforo/sangue , Fósforo na Dieta/sangue , Prognóstico , Diálise Renal , Medição de Risco , Fatores de Risco
15.
Bioresour Technol ; 338: 125529, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34265592

RESUMO

Removal of nitrogenous and phosphorus compounds from aquaculture wastewater by green microalgae (Tetraselmis sp.) was investigated using a novel method of algal cell immobilization. Immobilized microalgae removed nitrogenous and phosphorous compounds efficiently from aquaculture wastewater. Results showed that Tetraselmis beads reduced significantly (p < 0.05) the total ammonia nitrogen, nitrite nitrogen and soluble reactive phosphorous concentration (0.08; 0.10 and 0.17 mg/L, respectively) from the initial concentration of 7.7, 3.1 and 2.0 mg/L respectively within 48 h compared to other treatments. Removal rate of total ammonia nitrogen, nitrite nitrogen and soluble reactive phosphorous were 99.2, 99.2 and 94.3% respectively, for the artificial wastewater within 24 h. For the shrimp pond wastewater, total ammonia nitrogen, nitrite nitrogen and soluble reactive phosphorous were reduced 98.9, 97.7 and 91.1% respectively within 48 h. It is concluded that Tetraselmis sp. beads is an effective means to reduce nitrogen and phosphorus levels in aquaculture wastewater.


Assuntos
Microalgas , Compostos de Fósforo , Aquicultura , Biomassa , Nitrogênio/análise , Fósforo , Águas Residuárias
16.
Environ Pollut ; 288: 117732, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34256284

RESUMO

Phosphorus (P) discharges from human activities result in eutrophication of lakes. We investigated whether the forms of phosphorus (P) in rivers with high effluent loads flowing through urban areas of Sapporo, Japan, were transformed when transported downstream into a eutrophic lake, namely Lake Barato. We hypothesized that the inorganic P supplied from the rivers might be transformed to organic forms in the lake. The results showed that soluble reactive phosphorus (SRP) and particulate inorganic phosphorus (PIP) dominated in the river discharge to the lake. Suspended solids in the rivers were rich in iron (Fe) so PIP was associated with Fe. A comparison of the concentrations at the river mouth and 4.5 km downstream showed that the concentrations of SRP and PIP were lower at 4.5 km downstream than at the river mouth, whereas the concentrations of organic P (i.e., dissolved organic phosphorus and particulate organic phosphorus) were similar. The results from solution 31P nuclear magnetic resonance spectroscopy of lake water showed that pyrophosphate was only present in the particulate fraction, while orthophosphate diesters (DNA-P) were only present in the dissolved fraction. Riverine samples contained orthophosphate (ortho-P) only, while lake samples contained ortho-P, orthophosphate monoesters, and DNA-P. The results suggest that the P forms, particularly those of dissolved P, shifted from inorganic to organic forms as the water was discharged from the river to the lake.


Assuntos
Compostos de Fósforo , Poluentes Químicos da Água , China , Monitoramento Ambiental , Eutrofização , Humanos , Lagos , Espectroscopia de Ressonância Magnética , Fósforo/análise , Compostos de Fósforo/análise , Rios , Poluentes Químicos da Água/análise
17.
Chembiochem ; 22(21): 3001-3009, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34289217

RESUMO

Known since the 1890s, diamidophosphate (DAP) has been investigated within the context of its inorganic chemistry. In 1999 - with the demonstration of DAP's potential as a phosphorylating agent of sugars in aqueous medium - began the exciting phase of research about DAP's role as a plausible prebiotic phosphorylating agent. More recently, in the last five years, there has been a steady increase in the publications that have documented the surprising versatility of DAP enabling the emergence of many classes of biomolecules of life, such as nucleic acids, peptides and protocells. Thus, though in its infancy, DAP seems to be uniquely positioned to play a central role in modelling abiotic- to prebiotic-chemical evolution. In this context, there is a need for systematic investigations for: (a) establishing DAP's likely availability on the early Earth, and (b) developing DAP's potential as a tool for use in synthetic and bioorganic chemistry.


Assuntos
Indicadores e Reagentes/metabolismo , Compostos de Fósforo/metabolismo , Planeta Terra , Evolução Química , Indicadores e Reagentes/química , Compostos de Fósforo/química , Fosforilação
18.
Bioprocess Biosyst Eng ; 44(10): 2153-2166, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34057575

RESUMO

Expensive cellulase and complex detoxification procedures increase the cost of biomass lactic acid fermentation. Therefore, it is of great significance to develop a robust method to ferment lactic acid using biomass by avoiding cellulase and detoxification. This study demonstrates the advantage of combining mechanocatalytic P2O5 pre-treatment and strain domestication. We show that an enzyme-free mechanocatalytic saccharification process by combining mix-milling of P2O5 with biomass and successive hydrolysis produces a fermentable hydrolysate with much less inhibitory compounds than the hydrolysates obtained by conventional methods; only 5-HMF, furfural and acetic acid were detected in the biomass hydrolysate, and no phenolic inhibitors were detected. Pretreatment of biomass with P2O5 not only avoided cellulase, but also obtained less toxic hydrolysate. Furthermore, the Pediococcus pentosaceus strain gained superior inhibitor tolerance through domestication. It could tolerate 17.1 g/L acetic acid, 12.5 g/L 5-HMF, 11.9 g/L guaiacol and 11.5 g/L furfural and showed activity in decomposing furfural and 5-HMF for self-detoxification, allowing efficient lactic acid fermentation from biomass hydrolysate without detoxification. The lactic acid concentration and conversion rate fermented by domesticated bacteria were increased by 113.5% and 22.4%, respectively. In addition, the domesticated bacteria could utilize glucose and xylose simultaneously to produce lactic acid selectively. The combination of P2O5 pre-treatment and strain domestication to ferment lactic acid is applied to several biomass feedstocks, including corn stalk, corn stalk residue and rice husk residue. Lactic acid concentrations of 29.8 g/L, 31.1 g/L, and 46.2 g/L were produced from the hydrolysates of corn stalk, corn stalk residue and rice husk residue, respectively.


Assuntos
Ácido Láctico/biossíntese , Pediococcus pentosaceus/efeitos dos fármacos , Compostos de Fósforo/farmacologia , Biomassa , Cromatografia Líquida de Alta Pressão , Fermentação , Hidrólise , Oryza/metabolismo , Espectrofotometria Ultravioleta , Zea mays/metabolismo
19.
Bioconjug Chem ; 32(6): 1117-1122, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34030446

RESUMO

A cyclotriphosphazene-based "butterfly" fluorescence probe HCCP-MNI bearing two naphthalimide and morpholine units were developed for lysosome targeting. The synthesized HCCP-MNI exhibited stable fluorescence signals and was cytocompatible in the given concentration range. Co-localization experimental results showed that cells treated with the HCCP-MNI and a commercial dye (Lyso-Tracker Red DND-99) had overlapped fluorescence signals, demonstrating its targeting specificity to lysosomes. The developed HCCP-MNI may be used for cell tracking applications associated with the functionalities of lysosomes.


Assuntos
Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Lisossomos/metabolismo , Compostos de Fósforo/química , Espectrometria de Fluorescência
20.
J Xray Sci Technol ; 29(2): 373-382, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33554936

RESUMO

The main objective of this work is to explore the X-ray interaction properties of P2O5- SnCl2-SnO bioactive glass system using Photon Shielding and Dosimetry (Phys-X/PSD) software in the energy range 10-150 keV. The study of these parameters will have applications in various fields of nuclear medicine, medical technology, and other medical applications. The value of mass attenuation coefficients (µm) and effective atomic numbers (Zeff) decrease whereas the value of mean free path as well as half value layer increases with rises in energy in the selected energy range. The study results indicate that bioactive glass composition of T2 of chemical composition (35P2O5- 55SnCl2-10SnO) possesses the lowest value of mean free path (MFP), and highest value of µm, and Zeff, among the chemical composition.


Assuntos
Fótons , Radiometria , Compostos de Fósforo , Radiografia , Raios X
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