Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Environ Monit Assess ; 196(5): 494, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691200

RESUMO

This study investigated the impact of soil type, pH, and geographical locations on the accumulation of arsenic (As), lead (Pb), and cadmium (Cd) in rice grains cultivated in Ghana. One hundred rice farms for the sampling of rice grains and soil were selected from two regions in Ghana-Volta and Oti. The concentrations of As, Pb, and Cd were analyzed using ICP-OES. Speciation modeling and multivariate statistics were employed to ascertain the relations among measured parameters. The results showed significant variations in soil-As, Pb, and Cd levels across different soil types and pH ranges, with the highest soil-As and Cd found in alkaline vertisols. For soil-As and Cd, the vertisols with a pH more than 7.0 exhibited the highest mean concentration of As (2.51 ± 0.932 mgkg-1) and Cd (1.00 ± 0.244 mgkg-1) whereas for soil-Pb, the luvisols of soil types with a pH less than 6.0 exhibited the highest mean concentration of Pb (4.91 ± 1.540 mgkg-1). Grain As, Pb, and Cd also varied across soil types and pH levels. In regards to grain-As, the vertisols soil type, with a pH less than 6.0, shows the highest mean concentration of grain As, at 0.238 ± 0.107 mgkg-1. Furthermore, vertisols soil types with a pH level less than 6.0 showed the highest mean concentration of grain Cd, averaging at 0.231 ± 0.068 mgkg-1 while luvisols, with a pH less than 6.0, exhibited the highest mean concentration of grain Pb at 0.713 ± 0.099 mgkg-1. Speciation modeling indicated increased bioavailability of grains Cd2+ and Pb2+ ions in acidic conditions. A significant interaction was found between soil-Cd and pH, affecting grain-As uptake. The average concentrations of soil As, Pb, and Cd aligned with international standards. Generally, the carcinogenic metals detected in grain samples collected from the Volta region are higher than that of the Oti region but the differences are insignificant, and this may be attributed to geographical differences and anthropogenic activities. About 51% of the study area showed a hazard risk associated with grain metal levels, although, no carcinogenic risks were recognized. This study highlights the complex soil-plant interactions governing metal bioaccumulation and emphasizes the need for tailored strategies to minimize metal transfer into grains.


Assuntos
Arsênio , Cádmio , Monitoramento Ambiental , Oryza , Poluentes do Solo , Solo , Poluentes do Solo/análise , Gana , Solo/química , Oryza/química , Cádmio/análise , Concentração de Íons de Hidrogênio , Arsênio/análise , Chumbo/análise , Agricultura
2.
Environ Technol ; 35(21-24): 2761-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25176478

RESUMO

Agro-waste from the bark of Metroxylon sagu (sago) was studied as a low cost and effective oil sorbent in dry and aqueous environments. Sorption study was conducted using untreated sago bark (SB) and esterified sago bark (ESB) in used engine oil. Characterization study showed that esterification has successfully improved the hydrophobicity, buoyancy, surface roughness and oil sorption capacity of ESB. Sorption study revealed that water uptake of SB is higher (30 min static: 2.46 g/g, dynamic: 2.67 g/g) compared with ESB (30 min static: 0.18 g/g, dynamic: 0.14 g/g). ESB, however, showed higher oil sorption capacity in aqueous environment (30 min static: 2.30 g/g, dynamic: 2.14) compared with SB (30 min static: 0 g/g, dynamic: 0 g/g). ESB has shown great poTENTial as effective oil sorbent in aqueous environment due to its high oil sorption capacity, low water uptake and high buoyancy.


Assuntos
Arecaceae , Óleos/química , Casca de Planta/química , Poluentes Químicos da Água/química , Adsorção , Agricultura , Recuperação e Remediação Ambiental , Esterificação , Reciclagem , Resíduos
3.
Curr Top Med Chem ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38847246

RESUMO

Flavonoids belong to the polyphenol group that naturally exists in fruits, vegetables, tea, and grains. Flavonoids, as secondary metabolites, show indispensable contributions to biolog-ical processes and the responses of plants to numerous environmental factors. The bioactivity of flavonoids depends on C6-C3-C6 ring substitution patterns that exhibit bioactive antioxidant, an-timicrobial, antifungal, antitumor, and anti-inflammatory properties. The synthesis of flavonoids has been reported by various methodologies. Therefore, the present review systematically sum-marizes the synthesis of recent heterocyclic flavonoid derivatives via facile synthetic approaches since the research in flavonoids is useful for therapeutic and biotechnology fields.

4.
Environ Sci Pollut Res Int ; 31(18): 27099-27116, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503949

RESUMO

This research provides a comprehensive analysis of groundwater pollution in the Lower Anayari Catchment (LAC) through δ2H and δ18O isotopic analysis, along with positive matrix factorization (PMF) and PCS-MLR receptor models. Forty groundwater samples were collected from hand-dug wells and equipped boreholes across the LAC. Flame photometry for Na+ and K+, complexometric titration for Ca2+, ion chromatography for Cl-, F-, NO3-, SO42-, and PO43-, and atomic absorption spectrometry for Mg2+, Fe, Pb, Cd, As, and Ni were analytical techniques/instruments employed. In regard to cations, Na+ has the highest average concentration of 63.0 mg/L, while Mg2+ has the lowest at 2.58 mg/L. Concerning the anions and nutrients, Cl- has the highest mean concentration of 18.7 mg/L, and Fl- has the lowest at 0.50 mg/L. Metalloids were detected in trace amount with Fe displaying the highest mean concentration of 0.077 mg/L whereas Cd and As recorded lowest (0.001 mg/L). The average values for groundwater δ18O and δ2H were - 3.64‰ and - 20.7‰, respectively; the average values for rainwater isotopic composition were - 3.41‰ for δ18O and - 17.4‰ for δ2H. It is believed that natural geological features, particularly biotite granitoid and volcanic flow/subvolcanic rocks from the Birimian Supergroup, significantly influence groundwater mineralisation. Additionally, the impact of anthropogenic activities on water quality, with urban development and agricultural practices, may be attributed to increasing levels of certain contaminants such as Fe, Ni, NO3-, and PO43-. This research contributes to the broader field of hydrological study and provides practical implications for managing and conserving water resources in similar contexts. The innovative combination of isotopic and statistical analyses sets a new standard for future studies in groundwater quality assessment, emphasising the need for comprehensive approaches that consider both geological characteristics and human impacts for sustainable water resource management.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Poluentes Químicos da Água , Água Subterrânea/química , Poluentes Químicos da Água/análise
5.
Artigo em Inglês | MEDLINE | ID: mdl-24427019

RESUMO

The asymmetric unit of the title compound, C22H18N4O2S2, contains two mol-ecules. In one of them, the dihedral angles between the central benzene ring and the phenyl rings are 16.97 (8) and 20.97 (8)°, while the phenyl rings make a dihedral angle of 37.87 (8)°. In the other mol-ecule, the corresponding values are 34.92 (7), 53.90 (7) and 60.68 (8)°, respectively. In each mol-ecule, two intra-molecular N-H⋯O hydrogen bonds generate S(6) rings and a short C-H⋯S contact also occurs. In the crystal, N-H⋯S, N-H⋯O, C-H⋯O and C-H⋯S inter-actions link the mol-ecules into a three-dimensional network.

6.
Nat Prod Res ; : 1-11, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752781

RESUMO

Chemical modification of active scaffolds from natural products has gained interest in pharmaceutical industries. Nevertheless, the metabolites extraction is time-consuming while the lead is frequently mismatched with the receptor. Here, the diazo coupling approach was introduced to generate a series of vanillin derivatives featuring halogenated azo dyes (1a-h). The vanillin derivatives showed effective inhibition of S. aureus (7-9 mm) and E. coli (7-8 mm) compared to the parent vanillin, while 1b had the highest inhibition zone (9 mm) against S. aureus comparable to the reference ampicillin. The presence of N = N, C = O, -OH, -OCH3 and halogens established strategic binding interactions with the receptor. The potential vanillin-azo as an antimicrobial drug was supported by in silico docking with penicillin-binding proteins and DFT (using Gaussian 09) with binding affinity -7.5 kcal/mol and energy gap (Egap) 3.77 eV, respectively. This study represents a significant advancement in drug discovery for effective antibiotics with excellent properties.

7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2909, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125701

RESUMO

In the title compound, C(21)H(24)O(3), the enone moiety adopts an s-cis conformation and the dihedral angle between the benzene rings is 12.89 (6)°. The hex-yloxy tail adopts an extended conformation. In the crystal, inversion dimers are linked by pairs of O-H⋯O hydrogen bonds and pairs of C-H⋯O inter-actions, forming two R(2) (2)(7) and one R(2) (2)(10) loops. The dimers are then arranged into sheets lying parallel to (201) and weak C-H⋯π inter-actions consolidate the packing.

8.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2911-2, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125703

RESUMO

In the title compound, C(29)H(40)O(3), the enone moiety adopts an s-cis conformation. The dihedral angle between the benzene rings is 4.33 (5)° The least-squares mean line through the tetra-decyl side chain forms a dihedral angle of 83.99 (7)° with the normal to the attached benzene ring. In the crystal, O-H⋯O and C-H⋯O hydrogen bonds involving the keto and the hy-droxy O atoms form ribbons along [-41-1]. The crystal structure also features C-H⋯π inter-actions.

9.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2935-6, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125722

RESUMO

In the title compound, C(25)H(32)O(3), the enone group adopts an s-cis conformation. The alk-oxy chain is in an all-trans conformation. The dihedral angle between the benzene rings is 7.86 (5)°. In the crystal, mol-ecules are connected by pairs of O-H⋯O hydrogen bonds, forming inversion dimers and giving R(2) (2)(10) rings. Within these dimers, weak C-H⋯O hydrogen bonds form two R(2) (2)(7) rings. In the crystal, the approximately planar mol-ecules [largest deviation for an atom being 0.4737 (12) Šfor the terminal C atom of the alk-oxy chain] are arranged in sheets parallel to (20-1). Weak C-H⋯π inter-actions are also observed.

10.
Membranes (Basel) ; 12(10)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36295672

RESUMO

To meet the need for food products to be safe and fresh, smart food packaging that can monitor and give information about the quality of packaged food has been developed. In this study, pH-sensitive films with sago starch and various anthocyanin concentrations of Brassica oleracea also known as red cabbage anthocyanin (RCA) at 8, 10, 12, and 14% (w/v) were manufactured using the solvent casting process. Investigation of the physicochemical, mechanical, thermal, and morphological characteristics of the films was performed and analysed. The response of these materials against pH changes was evaluated with buffers of different pH. When the films were exposed to a series of pH buffers (pH 3, 5, 9, 11, and 13), the RCA-associated films displayed a spectacular colour response. In addition, the ability of the starch matrix to overcome the leaching and release of anthocyanins was investigated. Higher concentrations of RCA can maintain the colour difference of films after being immersed in a series of buffer solutions ranging from acidic to basic conditions. Other than that, incorporating RCA extracts into the starch formulation increased the thickness whereas the water content, swelling degree, tensile strength, and elongation at break decreased as compared to films without RCA. The immobilisation of anthocyanin into the film was confirmed by the FTIR measurements. The surface patterns of films were heterogeneous and irregular due to the presence of RCA extract aggregates, which increased as the extract concentration enhanced. However, this would not affect the properties of films. An increase in thermal stability was noted for the anthocyanin-containing films at the final stage of degradation in TGA analysis. It is concluded that RCA and sago starch formulation has great potential to be explored for food packaging purposes.

11.
Curr Org Synth ; 18(4): 318-332, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32778031

RESUMO

Latest progress in the liquid crystal (LC) field related to azo molecules incorporated into natural product- based moieties for the improvement of LC texture and mesomeric phases has received great interest among researchers. A LC containing natural product-based moieties i.e. menthol, kojic acid, cholesterol and chalcone with stable azo and azobenzene scaffolds with specific optical tunability, has been widely used in photo-active materials such as Liquid Crystal Display (LCD), LC films, smart windows and other devices. This review discusses the influence of azobenzene, a renowned photo-responsive and stable LC scaffold, in mesogenic phases due to photo-isomerization and optical switching. The incorporation of mesomeric phases of natural product moieties to azo molecules has improved the properties of LC, i.e, from the nematic phase to the smectic phase with proper magnetic field alignment. Natural product-based LC can be useful in numerous applications, especially practical electronic or optic devices such as optical image storage, display devices, solar cells, optical switching.

12.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3275-6, 2010 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-21589557

RESUMO

There are two mol-ecules in the asymmetric unit of the title compound, C(21)H(24)O(3), in which the dihedral angles between the aromatic rings are 6.4 (1) and 7.0 (1)°. The enone moiety of both mol-ecules adopts an s-cis configuration. In the crystal, inter-molecular O-H⋯O and C-H⋯O inter-actions to the same acceptor O atom generate R(2) (1)(6) ring motifs and further C-H⋯O inter-actions generate R(2) (2)(8) ring motifs. Topologically, the R(2) (1)(6) and R(2) (2)(8) ring motifs are arranged alternately, forming [001] chains of mol-ecules. The crystal structure is further stabilized by C-H⋯π inter-actions.

13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): o169-70, 2010 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-21522676

RESUMO

In the title compound, C(21)H(24)O(3), inter-molecular O-H⋯O and C-H⋯O inter-actions form bifurcated acceptor bonds, generating R(2) (1)(6) ring motifs. These ring motifs link the mol-ecules into extended chains along [010]. The crystal structure is further stabilized by C-H⋯π inter-actions.

14.
Protein J ; 39(1): 62-72, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31863255

RESUMO

Metroxylon sagu Rottb. or locally known as sago palm is a tropical starch crop grown for starch production in commercial plantations in Malaysia, especially in Sarawak, East Malaysia. This plant species accumulate the highest amount of edible starch compared to other starch-producing crops. However, the non-trunking phenomenon has been observed to be one of the major issues restricting the yield of sago palm starch. In this study, proteomics approach was utilised to discover differences between trunking and non-trunking proteomes in sago palm leaf tissues. Total protein from 16 years old trunking and non-trunking sago palm leaves from deep peat area were extracted with PEG fractionation extraction method and subjected to two-dimensional gel electrophoresis (2D PAGE). Differential protein spots were subjected to MALDI-ToF/ToF MS/MS. Proteomic analysis has identified 34 differentially expressed proteins between trunking and non-trunking sago samples. From these protein spots, all 19 proteins representing different enzymes and proteins have significantly increased in abundance in non-trunking sago plant when subjected to mass spectrometry. The identified proteins mostly function in metabolic pathways including photosynthesis, tricarboxylic acid cycle, glycolysis, carbon utilization and oxidative stress. The current study indicated that the several proteins identified through differentially expressed proteome contributed to physical differences in trunking and non-trunking sago palm.


Assuntos
Arecaceae , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Arecaceae/crescimento & desenvolvimento , Arecaceae/metabolismo , Expressão Gênica/fisiologia , Proteômica/métodos , Estresse Fisiológico
15.
Nat Prod Res ; 34(11): 1505-1514, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30507306

RESUMO

In searching for drugs from natural product scaffolds has gained interest among researchers. In this study, a series of twelve halogenated thiourea (ATX 1-12) via chemical modification of aspirin (a natural product derivative) and evaluated for cytotoxic activity against nasopharyngeal carcinoma (NPC) cell lines, HK-1 via MTS-based colorimetric assay. The cytotoxicity studies demonstrated that halogens at meta position of ATX showed promising activity against HK-1 cells (IC50 value ≤15 µM) in comparison to cisplatin, a positive cytotoxic drug (IC50 value =8.9 ± 1.9 µM). ATX 11, bearing iodine at meta position, showed robust cytotoxicity against HK-1 cells with an IC50 value of 4.7 ± 0.7 µM. Molecular docking interactions between ATX 11 and cyclooxygenase-2 demonstrated a robust binding affinity value of -8.1 kcal/mol as compared to aspirin's binding affinity value of -6.4 kcal/mol. The findings represent a promising lead molecule from natural product with excellent cytotoxic activity against NPC cell lines.


Assuntos
Antineoplásicos/farmacologia , Tioureia/toxicidade , Aspirina/análogos & derivados , Aspirina/metabolismo , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Halogênios/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Salix/química , Relação Estrutura-Atividade , Tioureia/análogos & derivados , Tioureia/metabolismo
16.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 4): o881-2, 2009 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21582591

RESUMO

In the title compound, C(25)H(32)O(3), the asymmetric unit contains two crystallographically independent mol-ecules: both enone groups adopt an s-cis configuration. In the crystal, O-H⋯O and C-H⋯O inter-molecular inter-actions form bifurcated hydrogen bonds, which generate R(1) (2)(6) ring motifs. These inter-molecular inter-actions link the mol-ecules into one-dimensional chains along the [10] direction. The crystal structure is further stabilized by C-H⋯π inter-actions.

17.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 4): o889-90, 2009 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21582598

RESUMO

In the title compound, C(25)H(32)O(3), the enone group is in an s-cis configuration. The dihedral angle between the benzene rings is 8.84 (7)°. An intra-molecular O-H⋯O inter-action between the keto and hydr-oxy groups forms an S(6) ring motif. Inter-molecular C-H⋯O inter-actions link the mol-ecules into supra-molecular chains along the c axis which are subsequently stacked down the b axis; the crystal structure is further consolidated by C-H⋯π inter-actions.

18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): o1301-2, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21583159

RESUMO

In the title compound, C(21)H(24)O(3), the conformation of the enone group is s-cis. The benzene rings are inclined at an angle of 7.9 (1)°. The alk-oxy tail is planar, with a maximum deviation from the least-squares plane of 0.009 (2) Å, and adopts a trans conformation throughout. An intra-molecular O-H⋯O inter-action between the keto and hydr-oxy groups forms S(6) ring motifs. In the crystal, mol-ecules are arranged in a head-to-tail manner down the a axis and are subsequently stacked along the b axis, forming mol-ecular sheets parallel to the ab plane. The crystal structure is further stabilized by weak C-H⋯π inter-actions and short C⋯O [3.376 (2) Å] contacts.

19.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): o1439-40, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-21583279

RESUMO

In the title compound, C(21)H(24)O(3), the enone group adopts an s-cis conformation. The planes of the aromatic rings are inclined at an angle of 6.1 (1)°. The alk-oxy tail is not linear, with the maximum deviation from the least-squares plane being 0.375 (2) Å. Mol-ecules are connected into extended chains along the a axis through O-H⋯O(carbon-yl) hydrogen bonds and are inter-linked via C-H⋯O inter-actions to form a two-dimensional array parallel to the ab plane.

20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): o1092-3, 2009 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21583907

RESUMO

In the title compound, C(25)H(32)O(3), the enone group adopts an s-cis conformation. The alk-oxy unit is nearly planar and is in a trans conformation. The two benzene rings make a dihedral angle of 18.87 (9)°. In the crystal structure, mol-ecules are linked into chains running along the a axis by inter-molecular O-H⋯O hydrogen bonds involving the hydr-oxy and keto groups. The chains are crosslinked along the b axis via C-H⋯O hydrogen bonds, forming a two-dimensional network parallel to the ab plane.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa