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1.
Planta ; 255(4): 87, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303194

RESUMO

MAIN CONCLUSION: A critical investigation into arsenic uptake and transportation, its phytotoxic effects, and defense strategies including complex signaling cascades and regulatory networks in plants. The metalloid arsenic (As) is a leading pollutant of soil and water. It easily finds its way into the food chain through plants, more precisely crops, a common diet source for humans resulting in serious health risks. Prolonged As exposure causes detrimental effects in plants and is diaphanously observed through numerous physiological, biochemical, and molecular attributes. Different inorganic and organic As species enter into the plant system via a variety of transporters e.g., phosphate transporters, aquaporins, etc. Therefore, plants tend to accumulate elevated levels of As which leads to severe phytotoxic damages including anomalies in biomolecules like protein, lipid, and DNA. To combat this, plants employ quite a few mitigation strategies such as efficient As efflux from the cell, iron plaque formation, regulation of As transporters, and intracellular chelation with an array of thiol-rich molecules such as phytochelatin, glutathione, and metallothionein followed by vacuolar compartmentalization of As through various vacuolar transporters. Moreover, the antioxidant machinery is also implicated to nullify the perilous outcomes of the metalloid. The stress ascribed by the metalloid also marks the commencement of multiple signaling cascades. This whole complicated system is indeed controlled by several transcription factors and microRNAs. This review aims to understand, in general, the plant-soil-arsenic interaction, effects of As in plants, As uptake mechanisms and its dynamics, and multifarious As detoxification mechanisms in plants. A major portion of this article is also devoted to understanding and deciphering the nexus between As stress-responsive mechanisms and its underlying complex interconnected regulatory networks.


Assuntos
Arsênio , Arsênio/metabolismo , Arsênio/toxicidade , Transporte Biológico , Produtos Agrícolas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Fitoquelatinas/metabolismo
2.
Mol Cell Biochem ; 477(4): 1041-1052, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34994923

RESUMO

Cytotoxic chemotherapy dominates the field of cancer treatment. Consequently, anticancer phytochemicals are largely screened on the basis of their cytotoxicity towards cancer cells which are achieved at higher doses, leading to various toxic side effects. Some phytochemicals also showed pro-carcinogenic effects at certain doses. The concept of hormesis has taught us to look into biphasic responses of phytochemicals in a more systematic way. Interestingly, the monoterpenoid alcohol, linalool, also has been reported to display both anti-oxidant and pro-oxidant properties, which prompted us to explore a probable biphasic effect on cancer cells. Cytotoxicity of various concentrations of linalool (0.1-4 mM) was tested on B16F10 murine melanoma cell line, and two sub-lethal concentrations (0.4 and 0.8 mM) were selected for further experiments. 0.4 mM linalool inhibited angiogenesis and metastasis, while 0.8 mM increased them. Similarly, B16F10 cell migration, invasion, and epithelial-mesenchymal transition markers also showed inhibition and induction with lower and higher linalool concentrations, respectively. Chorioallantoic membrane assay, scratch wound assay, and Boyden's chamber were used to analyze angiogenesis and metastasis. Expression of molecular markers such as vascular endothelial growth factor (VEGF) and its receptor phosphorylated VEGF receptor II (p-VEGFRII or p-Flk-1), Hypoxia-inducible factor-1 α (HIF-1α), E-cadherin, and vimentin were detected using Western blot, ELISA, PCR, qPCR, and immunofluorescence. Finally, ChIP assay was performed to evaluate HIF-1α association with VEGF promoter. Interestingly, measurement of intracellular reactive oxygen species at the selected concentrations of linalool using DCFDA in a flow cytometer showed that the phytochemical induced significant amount of ROS at 0.8 mM. This work sheds light on bimodal dose-response relationship exhibited by dietary phytochemicals like linalool, and it should be taken into consideration to elicit a desirable therapeutic effect.


Assuntos
Monoterpenos Acíclicos/farmacologia , Melanoma Experimental , Neovascularização Patológica , Animais , Embrião de Galinha , Células HEK293 , Humanos , Melanoma Experimental/sangue , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Metástase Neoplásica , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia
3.
Environ Res ; 214(Pt 3): 114059, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35961545

RESUMO

Phthalates are a family of reprotoxicant compounds, predominantly used as a plasticizer to improve the flexibility and longevity of consumable plastic goods. After their use these plastic products find their way to the waste disposal sites where they leach out the hazardous phthalates present within them, into the surrounding environment, contaminating soil, groundwater resources, and the nearby water bodies. Subsequently, phthalates move into the living system through the food chain and exhibit the well-known phenomenon of biological magnification. Phthalates as a primary pollutant have been classified as 1B reprotoxicants and teratogens by different government authorities and they have thus imposed restrictions on their use. Nevertheless, the release of these compounds in the environment is unabated. Bioremediation has been suggested as one of the ways of mitigating this menace, but studies regarding the field applications of phthalate utilizing microbes for this purpose are limited. Through this review, we endeavor to make a deeper understanding of the cause and concern of the problem and to find out a possible solution to it. The review critically emphasizes the various aspects of phthalates toxicity, including their chemical nature, human health risks, phytoaccumulation and entry into the food chain, microbial role in phthalate degradation processes, and future challenges.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Humanos , Ácidos Ftálicos/química , Ácidos Ftálicos/toxicidade , Plastificantes/química , Plastificantes/toxicidade , Plásticos
4.
J Food Sci Technol ; 55(9): 3809-3820, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30150841

RESUMO

This present study was aimed to evaluate proximate composition, antioxidant activity, amino and phenolic acids, protein profile and pasting characteristics of pigmented rice (PR) and non pigmented rice (NPR) landraces grown in Himalayan region. Higher antioxidant activity, total phenolic content, fat and protein content were observed for PR as compared to NPR. Histidine, iso-leucine, lysine, methionine, phenyl-alanine, valine and threonine were significantly higher for PR. Paste viscosities were higher for NPR (except IC568266) as compared to PR. IC568266 was observed to be waxy landrace. Higher free (gallic acid, catechin, caffeic acid, vanillic acid, sinapic acid and luteolin) and bound phenolics (ferulic acid, p-coumaric acid and quercetin) were observed in PR as compared to NPR. Majority of PR landraces showed higher accumulation of prolamines with low molecular weight polypeptides of 18, 20 and 29 kDa as compared to NPR. PR showed the higher essential amino acids, phenolic acids (p-coumaric acid, ferulic acid and quercetin) and antioxidant activity with improved nutritional value and showed potential for developing nutraceutical and functional foods.

5.
J Fluoresc ; 26(1): 355-62, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26555288

RESUMO

Live cells contain high concentrations of macromolecules, but almost all experimental biochemical data have been generated from dilute solutions that do not reflect conditions in vivo. To understand biomolecular behavior in vivo, properties studied in vitro are extrapolated to conditions in vivo. Another significant factor which is overlooked is the effects of macromolecular crowding and its consequences in the actual biochemical and physiological environment. Such influences of crowding, its modification and physiological parameters have been reported. The present study investigates the effect of molecular crowding on binding characteristics of Salmon sperm DNA with Bovine hemoglobin and their reconstitutes in presence of molecular crowders viz., Poly ethylene glycol (PEG) and Dextran of different molecular weight by fluorescence, UV visible spectroscopic technique at different temperatures. The results showed that BHb fluorescence was quenched by sDNA through static quenching mechanism which is enhanced in presence of polymers. The number of binding sites 'n' and binding constants 'K' were determined at different temperatures based on fluorescence quenching. The thermodynamic parameters namely ∆H°, ∆G°, T∆S° were studied at different temperatures and the results indicate that hydrophobic forces are predominant in the sDNA-BHb complex. Negative ∆G° values imply that the binding process is spontaneous.


Assuntos
DNA/química , Dextranos/química , Hemoglobinas/química , Polietilenoglicóis/química , Termodinâmica , Animais , Bovinos , Substâncias Macromoleculares/química , Masculino , Salmão , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espermatozoides
6.
J Food Sci Technol ; 53(8): 3186-3196, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27784913

RESUMO

The effects of transplantation date on milled rice (physicochemical, amino acids composition and protein profiling) of different cultivars and their starch characteristics (granules size distribution, pasting and thermal) were investigated. Head rice yield increased (2.0-4.1 %) and chalky grains (5-10 %) decreased with delaying the paddy transplantation of different cultivars by 20 days. Delayed transplantation of paddy significantly increased asparagine, glutamine, threonine, cysteine, methionine, tryptophan, lysine and proline content in milled rice. Early transplantation of paddy showed higher accumulation of glutelin and prolamines than that in milled rice from delayed transplantation. The change in amino acid composition of milled rice with delay in transplantation was related to variation in accumulation of glutelin and prolamines. Starch from delayed transplanted paddy showed higher peak viscosity and lower breakdown viscosity than those from early transplanted paddy. These differences were due to higher accumulation of amylose in starch from delayed transplanted paddy than that from early transplanted paddy due to exposure of former to lower night air temperature during starch synthesis.

7.
J Fluoresc ; 24(4): 1275-84, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24894381

RESUMO

Biological macromolecules evolve and function within intracellular environments that are crowded with other macromolecules. Crowding results in surprisingly large quantitative effects on both the rates and the equilibria of interactions involving macromolecules, but such interactions are commonly studied outside the cell in uncrowded buffers. The addition of high concentrations of natural and synthetic macromolecules to such buffers enables crowding to be mimicked in vitro, and should be encouraged as a routine variable to study. In this study, we propose to understand the changes in DNA character and its modulation in presence of macromolecules such as PEG with reference to binding parameters to amino acids using fluorescence enhancement.


Assuntos
Aminoácidos/química , DNA/química , Aminoácidos/análise , DNA/análise , Fluorescência , Substâncias Macromoleculares/análise , Substâncias Macromoleculares/química , Polietilenoglicóis/química , Espectrometria de Fluorescência , Termodinâmica
8.
Chemosphere ; 352: 141359, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309604

RESUMO

Dibutyl phthalate (DBP) is a widely used plasticizer to make plastic flexible and long-lasting. It is easily accessible in a broad spectrum of environments as a result of the rising level of plastic pollution. This compound is considered a top-priority toxicant and persistent organic pollutant by international environmental agencies for its endocrine disruptive and carcinogenic propensities. To mitigate the DBP in the soil, one DBP-degrading bacterial strain was isolated from a plastic-polluted landfill and identified as Paenarthrobacter ureafaciens PB10 by 16S rRNA gene sequence-based homology. The strain was found to develop a distinct transparent halo zone around grown colonies on an agar plate supplemented with DBP. The addition of yeast extract (100 mg/L) as a nutrient source accelerated cell biomass production and DBP degradation rate; however, the presence of glucose suppressed DBP degradation by the PB10 strain without affecting its ability to proliferate. The strain PB10 was efficient in eliminating DBP under various pH conditions (5.0-8.0). Maximum cell growth and degradation of 99.49% at 300 mg/L DBP were achieved in 72 h at the optimized mineral salt medium (MS) conditions of pH 7.0 and 32 °C. Despite that, when the concentration of DBP rose to 3000 mg/L, the DBP depletion rate was measured at 79.34% in 72 h. Some novel intermediate metabolites, like myristic acid, hexadecanoic acid, stearic acid, and the methyl derivative of 4-hydroxyphenyl acetate, along with monobutyl phthalate and phthalic acid, were detected in the downstream degradation process of DBP through GC-MS profiling. Furthermore, in synchronization with native soil microbes, this PB10 strain successfully removed a notable amount of DBP (up to 54.11%) from contaminated soil under microcosm study after 10 d. Thus, PB10 has effective DBP removal ability and is considered a potential candidate for bioremediation in DBP-contaminated sites.


Assuntos
Dibutilftalato , Micrococcaceae , Ácidos Ftálicos , Dibutilftalato/metabolismo , Biodegradação Ambiental , Ácido Mirístico , RNA Ribossômico 16S/genética , Ácidos Ftálicos/metabolismo , Solo
9.
Chempluschem ; 88(1): e202200299, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36646519

RESUMO

The present study focuses on generating mesopores within H-ZSM-5 (H-Z) zeolite via desilication and dealumination to incorporate Lewis acidic metal, such as Sn, into the framework (Sn4 ZS180 A15 ) to catalyse glucose isomerisation. Sn4 ZS180 A15 possesses enhanced surface area (457 m2 g-1 ), mesopore volume (0.585 cm3 g-1 ) and a high weak-medium to strong acidic sites ratio, compared to parent H-Z (395 m2 g-1 ; 0.174 cm3 g-1 ). DRS-UV-Vis and XPS results corroborate Sn incorporation into the framework of Sn4 ZS180 A15 , based on the absorbance peak around 200-220 nm and peaks appearing at 495.8 and 487.4 eV, respectively. Sn4 ZS180 A15 exhibits higher catalytic activity towards glucose isomerisation in ethanol-water at 110 °C, yielding 44.2 % fructose with 80.0 % selectivity. Conversely, the parent H-Z afforded negligible glucose conversion with a fructose yield of <1 % under identical conditions. Moreover, Sn-incorporated on dealuminated (Sn4 ZS0 A15 ) and desilicated (Sn4 ZS180 A0 ) catalysts give a low yield of fructose (7-10 %), signifying the requirement of the desilication-dealumination process before incorporating Sn into the framework.


Assuntos
Frutose , Glucose , Isomerismo , Água , Etanol
10.
ChemSusChem ; 15(17): e202200902, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-35713635

RESUMO

The present study focused on developing a stable basic MnOx support for Ru (RuMn) for the efficient oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) in water in the absence of an external base. A series of MnOx supports, synthesized via hydrothermal approach using urea as precipitant, was prepared by thermal treatment at various temperatures (300-800 °C) before doping with Ru. The RuMn-2 (1 wt % Ru, MnOx calcined at 400 °C) possessed a large number of basic sites (1.72 mmol g-1 ) based on CO2 temperature-programmed desorption analysis, affording an FDCA yield of 87 % with a turnover frequency of 22 h-1 . Transmission electron microscopy energy-dispersive X-ray spectroscopy elemental mapping of RuMn-2 showed a high dispersion of Ru over the surface of MnOx, contributing to the efficient HMF oxidation. Moreover, X-ray diffraction, X-ray photoelectron spectroscopy, and H2 temperature-programmed reduction indicated that the predominant MnO2 phase (ϵ-MnO2 ) played a vital role in HMF oxidation. RuMn-2 was recyclable for up to four runs without significant loss in the activity and retained its structural integrity.


Assuntos
Compostos de Manganês , Óxidos , Catálise , Ácidos Dicarboxílicos , Furaldeído/análogos & derivados , Furanos , Compostos de Manganês/química , Óxidos/química
11.
Bioresour Technol ; 361: 127661, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35872278

RESUMO

The intricate nature and rigidity of rice straw, particularly the presence of lignin and silica, hinders the catalytic valorization, consequently decreasing the yield of target products. This study reports the concurrent removal of lignin and silica from rice straw to obtain enriched holocellulose, then transforming it to furfural (FUR) and levulinic acid (LA). Interestingly, rice straw in the form of powder displays an improved removal of lignin (51.0%) and silica (92.0%) during ammonia treatment. Encouragingly, adding organic solvents, such as THF, to the aqueous system during the pretreatment of rice straw improves the lignin removal to 60.0%. Upon improving lignin removal to 60%, the obtained holocellulose enriched solid residue yields 71.0% FUR along with 52.0% LA, which is 8 and 4-fold higher than what is obtained with parent rice straw, signifying the importance and the prerequisite of lignin and silica removal from rice straw.


Assuntos
Lignina , Oryza , Amônia , Hidrólise , Lignina/química , Oryza/química , Dióxido de Silício , Solventes/química
12.
J Environ Pathol Toxicol Oncol ; 41(3): 13-32, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35993953

RESUMO

The use of platinum (Pt)-based anticancer drugs, although widespread in clinical practice, is severely limited due to toxic side-effects. One of the strategies for making Pt-based chemotherapy more effective is the synthesis and use of Pt nanoparticles (PtNPs). However, increasing evidence suggestD that nanoplatinum also pose potential risk to human health. This study examined the toxicity and anticancer activity of mycosynthesized PtNPs against sarcoma-180 (S-180) cells in vitro and in vivo. Curvularia affinis Boedijn, a phyto-pathogenic fungi isolated from rice, was used to synthesize PtNPs (named as CaPtNP). Well dispersed, mostly spherical CaPtNPs, with sizes ranging from 3-9 nm were characterized by Transmission electron microscopy (TEM), field emission scanning electron microscopy, X-ray diffraction, atomic force microscopy, and Fourier transform infrared spectrometry. Two concentrations of the CaPtNPs (2.31 and 4.63 ng/mL) were selected based on in vitro cytotoxicity assay on erythrocytes and peripheral blood mononuclear cells. The selected doses were found to induce significant in vitro and in vivo anti-proliferative and pro-apoptotic activity in S-180 cells. Elevated levels of pro-apoptotic markers (p53, Bax/Bcl2 ratio, Cyt c, caspase-3, cleaved PARP) and reduced BrdU incorporation validated the anticancer activity of CaPtNPs. The antitumor activity was further confirmed in S-180 transplanted tumor bearing mice. Moreover, examination of the impact of sub-chronic exposure (three months) of CaPtNPs on the ultra-structural features of renal and hepatic tissue by TEM revealed no significant toxicological manifestation in these organs. The CaPtNPs were also found to reduce oxidative stress and improve liver function in tumor bearing mice compared with untreated controls. Thus, this green CaPtNPs was well tolerated in mice and displayed significant antitumor property.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Animais , Antineoplásicos/farmacologia , Curvularia , Humanos , Leucócitos Mononucleares , Camundongos , Platina/química , Platina/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
13.
ACS Omega ; 6(41): 27247-27258, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34693145

RESUMO

The efficient removal of silica from rice straw and separation of its major components is essential for further valorization to produce value-added products. With regard to this, the isolation of cellulose (CEL), hemicellulose (HEM), and lignin (LIG) is imperative but quite challenging. Among several pretreatments of lignocellulosic biomass, the organosolv approach is deemed as one of the promising methods. Here, we present two different two-step approaches for the removal of silica and disintegration of significant components from rice straw, especially CEL; (i) base pretreatment, followed by organosolv treatment in the presence of organic acid, and (ii) organosolv pretreatment in the presence of organic acid, followed by base treatment. After each treatment, the recovered solid components are confirmed by various characterization techniques such as Fourier-transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, and thermogravimetric analysis. Method 2 demonstrates 82% total removal of HEM and LIG along with 90.4% of silica removal from rice straw to obtain CEL. Furthermore, the obtained crude CEL is found to be with a purity of 78%. Excellent removal of silica (90.4%) reflects that in a test study, the crude CEL obtained from method 2 gives a higher yield of butyl glucosides (59.6%) than rice straw, which affords 45.0% of butyl glucosides.

14.
Microbiol Res ; 250: 126809, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34166969

RESUMO

The toxic metalloid arsenic (As), is a major pollutant of soil and water, imposing severe health concerns on human lives. It enters the food chain mainly through As-contaminated crops. The uptake, translocation and accumulation of As in plant tissue are often controlled by certain soil-inhabiting microbial communities. Among them, indigenous, free-living As-resistant plant growth-promoting rhizobacteria (PGPR) plays a pivotal role in As-immobilization. Besides, the plant's inability to withstand As after a threshold level is actively managed by these PGPR increasing As-tolerance in host plants by a synergistic plant-microbe interaction. The dual functionality of As-resistant PGPR i.e., phytostimulation and minimization of As-induced phytotoxic damages are one of the main focal points of this review article. It is known that such PGPR having the functional arsenic-resistant genes (in ars operon) including As-transporters, As-transforming genes contributed to the As accumulation and detoxification/transformation respectively. Apart from assisting in nutrient acquisition and modulating phytohormone levels, As-resistant PGPR also influences the antioxidative defense system in plants by maneuvering multiple enzymatic and non-enzymatic antioxidants. Furthermore, they are effective in reducing membrane damage and electrolyte leakage in plant cells. As-induced photosynthetic damage is also found to be salvaged by As-resistant PGPR. Briefly, the eco-physiological, biochemical and molecular mechanisms of As-resistant PGPR are thus elaborated here with regard to the As-exposed crops.


Assuntos
Arsênio/farmacologia , Biodegradação Ambiental , Produtos Agrícolas/microbiologia , Desenvolvimento Vegetal , Rhizobiaceae/fisiologia , Poluentes do Solo/metabolismo , Solo/química , Arsênio/análise , Produtos Agrícolas/efeitos dos fármacos , Raízes de Plantas/microbiologia
15.
Dermatol Surg ; 36(12): 2030-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21040124

RESUMO

BACKGROUND: Infantile hemangiomas (IHs) are the most common benign tumors of infancy and may need to be treated in some cases. Oral corticosteroids are the mainstay of therapy but are not without their attendant side effects. OBJECTIVES: To evaluate the efficacy of combination therapy with oral corticosteroids and polidocanol sclerotherapy in hemangiomas needing treatment. PATIENTS AND METHODS: Eight children with IHs were started on oral prednisolone 3 to 4 mg/kg per day and fortnightly sclerotherapy with 3% polidocanol solution. The outcome was evaluated on the basis of color, turgidity of the lesion, ongoing growth, and assessment by parents and physician. Serial photographic records were maintained. The response was graded as excellent, good, poor, or nil. Complications were recorded. RESULTS: Four male and four female patients presented at a mean age of 4.6 months. The average area of the lesions was 40.6 cm(2) . The mean duration of treatment with steroids at full dose was 8.2 weeks and mean total duration of treatment was 28.6 weeks. Mean number of sclerotherapy sessions required was 4.7. Complications included ischemic necrosis, rebound growth, and ulceration. CONCLUSION: Combining oral corticosteroids with polidocanol sclerotherapy produced excellent results in the patients treated, with minimal attendant side effects.


Assuntos
Corticosteroides/uso terapêutico , Hemangioma Capilar/terapia , Polietilenoglicóis/uso terapêutico , Prednisolona/uso terapêutico , Soluções Esclerosantes/uso terapêutico , Escleroterapia/métodos , Administração Oral , Corticosteroides/administração & dosagem , Terapia Combinada , Feminino , Humanos , Lactente , Masculino , Polidocanol , Polietilenoglicóis/administração & dosagem , Prednisolona/administração & dosagem , Estudos Prospectivos , Soluções Esclerosantes/administração & dosagem , Resultado do Tratamento
16.
ChemSusChem ; 12(1): 145-163, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30362263

RESUMO

5-Hydroxymethylfurfural (HMF) is one of the versatile platform molecules that can be derived from biomass, and a promising starting substrate for producing 2,5-diformylfuran (DFF) and 2,5-furandicarboxylic acid (FDCA). DFF is a platform chemical with applications in pharmaceuticals, macrocyclic ligands, and functional polymeric materials. Importantly, FDCA is being considered as a potential alternative to replace terephthalic acid for producing the bioplastic polyethylene furanoate, instead of polyethylene terephthalate, by blending with ethylene glycol. A significant number of studies have focused on the oxidation of HMF to FDCA with metal-containing heterogeneous catalysts in both aqueous and organic media in the presence of peroxides/air/molecular oxygen as the oxidant. In this regard, articles have recently been published related to HMF oxidation with base (nonprecious)-metal-containing catalysts that exhibit appealing activity towards DFF or FDCA in terms of yield. Thus, this Minireview focuses on recent developments in efficient transformations of HMF to DFF and FDCA with base-metal-containing heterogeneous catalysts in aqueous and organic media. This review further focuses on the direct transformation of glucose/fructose to DFF and/or FDCA with nonprecious-metal-containing catalysts in various solvents. Photocatalytic approaches for HMF oxidation with nonprecious metal- containing catalysts are also briefly discussed.

17.
Food Res Int ; 126: 108675, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31732053

RESUMO

Brown rice of different long-grain Indica cultivars was polished to variable degree of milling (DoM) to see the difference in proteins and starches characteristics in head (HR) and broken rice (BR). Study revealed differential accumulation of starch, fat and proteins in both HR and BR. Extended DoM of brown rice resulted in a progressive decrease in HR yield and increase in BR yield. The extended DoM caused a decrease in protein and fat content in both HR and BR, whereas; an increase in peak viscosity and final viscosity was observed. On the contrary, the setback viscosity of HR and BR of different rice cultivars was influenced by cultivars and extended DoM. Milled rice from different cultivars milled to 6% DoM showed higher levels of 59 kDa, 54 kDa, 51 kDa, 32 kDa, 31 kDa, 30 kDa, 28 kDa, 24 kDa, 23 kDa, 15 kDa, 13 and 12 kDa PPs, while 28 kDa, 24 kDa, 23 kDa, 15 kDa, 13 kDa and 12 kDa PPs was the least or not observed in BR. The major quantitative changes were observed in 28 kDa, 24 kDa, and 23 kDa PPs. MALDI-ToF/MS analysis revealed the identity of 28 kDa PP as 60S ribosomal protein L10a and glutelin type-D 1 proteins. Whereas, the identity of 24 and 23 kDa PP, respectively was established as pathogenesis-related protein 1 (Oryza sativa Japonica Group) and Oryza sativa 1-Cys peroxiredoxin A. HR showed the presence of highly condensed packaged starch granules with smooth edges, which were tightly imbibed in the proteins matrix. However, the inter-cultivar differences in the starch structure and packaging were also observed. On the contrary, BR revealed lesser accumulation of starch particles with abnormal protein filling and several fissures and cracks in the starch granules of BR of different cultivars.


Assuntos
Oryza/química , Proteínas de Plantas/análise , Proteínas de Plantas/química , Amido/análise , Amido/química , Manipulação de Alimentos , Índia , Microscopia Eletrônica de Varredura , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 11): 1712-1718, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31709095

RESUMO

In the title 1:1 cocrystal, C7H4ClNO4·C6H6N2O, nicotinamide (NIC) and 2-chloro-5-nitro-benzoic acid (CNBA) cocrystallize with one mol-ecule each of NIC and CNBA in the asymmetric unit. In this structure, CNBA and NIC form hydrogen bonds through O-H⋯N, N-H⋯O and C-H⋯O inter-actions along with N-H⋯O dimer hydrogen bonds of NIC. Further additional weak π-π inter-actions stabilize the mol-ecular assembly of this cocrystal.

19.
J Food Sci ; 83(11): 2761-2771, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30372786

RESUMO

The present study evaluated the effect of parboiling on milling, chemical constituents, pasting and cooking properties of different paddy varieties. Parboiling decreased L* and a* values and increased b* and head rice recovery. Parboiling significantly increased the protein content and antioxidant activity on a dry basis. Parboiling decreased whiteness, fat content, and paste viscosities. The parboiling process increased the hydrophobicity of rice from all the varieties. Parboiled milled rice showed higher free and bound phenolic acids as compared to unparboiled milled rice. Parboiled milled rice showed higher content of essential amino acid than unparboiled milled rice. Variety PB1121 was suited best for parboiling on the basis of total color (ΔE), protein content, essential amino acid, and phenolic acids among the evaluated paddy varieties. PRACTICAL APPLICATION: The present study revealed that parboiled milled rice had higher antioxidant activity, amino acids, ferulic acid, and p-coumaric acids. Indeed, parboiled milled rice showed better textural and nutritional properties and would be more suitable for canning, puffed rice and biryani (rice cooked with chicken/mutton).


Assuntos
Culinária/métodos , Proteínas de Grãos/análise , Oryza/química , Fenóis/análise , Antioxidantes/análise , Cor , Ácidos Cumáricos/análise , Temperatura Alta , Hidroxibenzoatos/análise , Paladar , Viscosidade
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