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1.
Water Res ; 246: 120713, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37839225

RESUMEN

Previous research suggested that two major groups of polyphosphate-accumulating organisms (PAOs), i.e., Ca. Accumulibacter and Tetrasphaera, play cooperative roles in enhanced biological phosphorus removal (EBPR). The fermentation of complex organic compounds by Tetrasphaera provides carbon sources for Ca. Accumulibacter. However, the viability of the fermentation products (e.g., lactate, succinate, alanine) as carbon sources for Ca. Accumulibacter and their potential effects on the metabolism of Ca. Accumulibacter were largely unknown. This work for the first time investigated the capability and metabolic details of Ca. Accumulibacter cognatus clade IIC strain SCUT-2 (enriched in a lab-scale reactor with a relative abundance of 42.8%) in using these fermentation products for EBPR. The enrichment culture was able to assimilate lactate and succinate with the anaerobic P release to carbon uptake ratios of 0.28 and 0.36 P mol/C mol, respectively. In the co-presence of acetate, the uptake of lactate was strongly inhibited, since two substrates shared the same transporter as suggested by the carbon uptake bioenergetic analysis. When acetate and succinate were fed at the same time, Ca. Accumulibacter assimilated two carbon sources simultaneously. Proton motive force (PMF) was the key driving force (up to 90%) for the uptake of lactate and succinate by Ca. Accumulibacter. Apart from the efflux of proton in symport with phosphate via the inorganic phosphate transport system, translocation of proton via the activity of fumarate reductase contributed to the generation of PMF, which agreed with the fact that PHV was a major component of PHA when lactate and succinate were used as carbon sources, involving the succinate-propionate pathway. Metabolic models for the usage of lactate and succinate by Ca. Accumulibacter for EBPR were built based on the combined physiological, biochemical, metagenomic, and metatranscriptomic analyses. Alanine was shown as an invalid carbon source for Ca. Accumulibacter. Instead, it significantly and adversely affected Ca. Accumulibacter-mediated EBPR. Phosphate release was observed without alanine uptake. Significant inhibitions on the aerobic phosphate uptake was also evident. Overall, this study suggested that there might not be a simply synergic relationship between Ca. Accumulibacter and Tetrasphaera. Their interactions would largely be determined by the kind of fermentation products released by the latter.


Asunto(s)
Betaproteobacteria , Fósforo , Fósforo/metabolismo , Fermentación , Protones , Reactores Biológicos , Betaproteobacteria/metabolismo , Polifosfatos/metabolismo , Lactatos/metabolismo , Alanina , Succinatos/metabolismo , Carbono/metabolismo , Acetatos/metabolismo
2.
Molecules ; 24(23)2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31766544

RESUMEN

Cancer is one of the foremost causes of death globally and also the major stumbling block of increasing life expectancy. Although the primary treatment of surgical resection, chemotherapy, and radiotherapy have greatly reduced the mortality of cancer, the survival rate is still low because of the metastasis of tumor, a range of adverse drug reactions, and drug resistance. For all this, it is relevant to mention that a growing amount of research has shown the anticarcinogenic effect of phytochemicals which can modulate the molecular pathways and cellular events include apoptosis, cell proliferation, migration, and invasion. However, their pharmacological potential is hindered by their low water solubility, low stability, poor absorption, and rapid metabolism. In this scenario, the development of nanotechnology has created novel formulations to maximize the potential use of phytochemicals in anticancer treatment. Nanocarriers can enhance the solubility and stability of phytochemicals, prolong their half-life in blood and even achieve site-targeting delivery. This review summarizes the advances in utilizing nanoparticles in cancer therapy. In particular, we introduce several applications of nanoparticles combined with apigenin, resveratrol, curcumin, epigallocatechin-3-gallate, 6-gingerol, and quercetin in cancer treatment.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Neoplasias/tratamiento farmacológico , Antineoplásicos Fitogénicos/química , Humanos , Nanopartículas/química
3.
Carbohydr Polym ; 92(1): 200-5, 2013 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-23218283

RESUMEN

The fructose polymer fructan was extracted from white garlic and fractionated using DEAE cellulose 52 and Sephadex G-100 columns to characterize its chemical composition and protective effect against ultraviolet radiation b (UVB) induced human keratinocyte (HaTaC) damage. Gel permeation chromatography, high performance anion exchange chromatography, infrared spectroscopy and 1D and 2D nuclear magnetic resonance spectroscopy were used to determine the chemical composition and functional characteristics of the garlic fructan (GF). GF was a homogeneous polysaccharide with a molecular weight of 4.54 × 10(3)Da. It was a member of the 1-kestose family, and it was composed of fructose and glucose at a ratio of 14:1. The main chain of GF was composed of (2→1)-ß-D-fructopyranose linked to a terminal (2→1)-α-D-glucopyranose at the non-reducing end and a (2→6)-ß-D-fructopyranose branched chain. The degree of polymerization was 28. Preliminary tests described herein indicated that GF may be effective in protecting HaTaC from UVB-induced damage.


Asunto(s)
Fructanos , Ajo/química , Protectores contra Radiación/farmacología , Trisacáridos/química , Línea Celular/efectos de los fármacos , Línea Celular/efectos de la radiación , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Cromatografía , Fructanos/química , Fructanos/aislamiento & purificación , Fructanos/farmacología , Humanos , Queratinocitos/efectos de la radiación , Espectroscopía de Resonancia Magnética , Peso Molecular , Protectores contra Radiación/química
4.
Ying Yong Sheng Tai Xue Bao ; 21(9): 2209-16, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21265139

RESUMEN

Taking the mixed leaf litters in broadleaved-Korean pine forests at different succession stages (secondary birch forest, selective cutting forest, and original mixed forest) and the leaf litters of the dominant tree species (Betula costata, Tilia amurensis, and Pinus koraiensis) in these forests in Xiaoxing' an Mountains, China as test objects, this paper studied their remaining rates and nutrient dynamics in October 2006-November 2008 by using decomposition bag method. For all test leaf litters, their remaining rate had an exponential relationship with time. The annual decomposition constant (k) ranged from 0.137 to 0.328, and the time for decomposing 50% (t50%) and 95% (t95%) was 2.340-4.989 years and 9.360-21.796 years, respectively. No significant differences were observed in the decomposition rates of the leaf litters among the forests, but the k value of the mixed leaf litters was decreased in the order of original mixed forest > selective cutting forest > secondary birch forest, while that of the dominant tree species leaf litters had no obvious pattern. During decomposition, the elements C, P, and K in leaf litters released continuously, and the release pattern of C followed linear function, while that of P and K followed a function of higher degree. Element N presented different levels of accumulation, but had no clear pattern.


Asunto(s)
Carbono/metabolismo , Ecosistema , Fósforo/metabolismo , Pinus/metabolismo , Hojas de la Planta/metabolismo , China , Pinus/crecimiento & desarrollo , Potasio/metabolismo , Tilia/crecimiento & desarrollo , Tilia/metabolismo
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