RESUMO
South Pars Industrial Energy Zone, located in the southwest of Iran along the Persian Gulf coast, encompasses many industrial units in the vicinity of urban areas. This research study investigated the effects of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) on human health and the environment. Suspended particulate matters (SPM) in the air sampled, in summer and winter 2019, from ten stations next to industrial units and residential areas. The samples were analyzed by gas chromatography-mass spectrometry (GC-MS). Spatial distribution maps of pollutants in the region were prepared using GIS software. The highest carcinogenic risk due to PAHs and PCBs measured as ([Formula: see text]) and ([Formula: see text], respectively. According to the US Environmental Protection Agency limit ([Formula: see text]), the cancer risks from PAH compounds were significant and need further investigation. The PCB cancer risks were within acceptable ranges. The highest adsorption ratios for PAHs were obtained through skin and PCBs by ingestion. The maximum measured non-carcinogenic hazard indexes (HI) turned out to be 0.037 and 0.023 for PAH and PCB, respectively, and were reported as acceptable risks. The predominant source of PAH in industrial areas was liquid fossil combustion, and in urban areas replaced by coal-wood-sugarcane combustion. Petrochemical complexes, flares, power plants (69%), electric waste disposal sites, and commercial pigments (31%) were reported as PCB sources. Industries activities were the most effective factors in producing the highest level of carcinogenic compounds in the region, and it is necessary to include essential measures in the reform programs.
Assuntos
Poluentes Atmosféricos , Neoplasias , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Compostos Policíclicos , Humanos , Bifenilos Policlorados/análise , Compostos Policíclicos/análise , Compostos de Bifenilo/análise , Monitoramento Ambiental/métodos , Irã (Geográfico) , Poeira/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Carcinógenos/toxicidade , Carcinógenos/análise , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Carvão Mineral/análise , Medição de Risco , Carcinogênese , Poluentes Atmosféricos/análiseRESUMO
According to current regulatory guidelines, a stability-indicating method has been developed to determine the impurities in sacubitril (SCB) and valsartan (VLS) tablet dosage forms and perform robustness studies using the design of experiments approach. The present study was initiated to understand quality target product profile, analytical target profile, and risk assessment for method variables that affect the method response. A reversed-phase-HPLC system was equipped with a Phenomenex Gemini-NX C18 column (150 × 4.6 mm, 3 µm) and a photo diode array detector. A gradient mobile phase was used in this research work. The detection was performed at 254 nm; the flow rate was 1.5 mL/min, and the column temperature was maintained at 30°C. The proposed method was validated per the International Council for Harmonisation Q2 (R1) guidelines. The coefficient of correlation was >0.999 for all impurities. The limits of detection and quantification were evaluated for SCB, VLS, and all impurities. The precision and accuracy were obtained for SCB, VLS, and their related impurities. Intra- and inter-day relative standard deviation values were less than 10.0%, and the recoveries of impurities varied between 90.0 and 115.0%. Based on the validation results, the proposed DoE method can estimate SCB and VLS impurities in the finished dosage form.
Assuntos
Aminobutiratos , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Valsartana , Aminobutiratos/análise , Aminobutiratos/química , Compostos de Bifenilo/análise , Compostos de Bifenilo/química , Cromatografia de Fase Reversa , Combinação de Medicamentos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Projetos de Pesquisa , Valsartana/análise , Valsartana/químicaRESUMO
Coffee is one of the most often consumed beverages almost all over the world. The multiplicity of beans, as well as the methods and parameters used to brew, encourages the optimization of the brewing process. The study aimed to analyze the effect of roasting beans, the brewing technique, and its parameters (time and water temperature) on antioxidant activity (determined using several in vitro methods), total polyphenols, flavonoids, and caffeine content. The infusions of unroasted and roasted Arabica beans from Brazil, Colombia, India, Peru, and Rwanda were analyzed. In general, infusions prepared from roasted beans had higher antioxidant activity and the content of above-mentioned compounds. The hot brew method was used to obtain infusions with a higher antioxidant activity, while the cold brew with higher caffeine content. The phenolic compound content in infusions prepared using both techniques depended on the roasting process. Moreover, the bean's origin, roasting process, and brewing technique had a significant effect on the tested properties, in contrary to brewing time and water temperature (below and above 90 °C), which had less impact. The results confirm the importance of coffee brewing optimization.
Assuntos
Café/química , Antioxidantes/análise , Bebidas , Compostos de Bifenilo/análise , Brasil , Cafeína/análise , Coffea/química , Colômbia , Índia , Peru , Fenóis/análise , Extratos Vegetais/química , Polifenóis/análise , Sementes/química , Temperatura , Fatores de Tempo , Água/químicaRESUMO
A new type of multigrain snack has been designed containing varied additions of Moldavian dragonhead (Dracocephalum moldavica L.) seeds. The antioxidant properties and the general health benefits of this plant material have already been widely acknowledged. The research discussed herein aimed to investigate the influence of the formulation and expansion method (frying) on the content of polyphenolic compounds, individual phenolic acids, and antiradical properties of innovative snacks enriched with dragonhead seeds. The highest content of polyphenols (0.685 mg GAE/mL), free phenolic acids (47.052 µg/g of dry matter), and highest radical scavenging activity (96.23% towards DPPH) were found in the fried snacks enriched with 22% of seeds. In these samples, 11 phenolic acids were detected. Strong positive correlations were seen between the addition of dragonhead and the polyphenol content (r = 0.989) and between the quantity of the enriching additive and the content of free phenolic acids (r = 0.953). The research has shown that such innovative snacks have the potential to supply health-benefiting free phenolic acids, e.g., salicylic, isoferulic, ferulic, p-coumaric, vanillic. Our studies provide an introduction to the development of a new range of functional foods.
Assuntos
Compostos de Bifenilo/análise , Alimento Funcional/análise , Hidroxibenzoatos/análise , Lamiaceae/química , Picratos/análise , Polifenóis/análise , Lanches , Extratos Vegetais/análise , Sementes/químicaRESUMO
A novel surface plasmon resonance-based P-gp ligand screening system (SPR-PLSS) combined with lentiviral particle (LVP) stabilization strategy was constructed to screen out potential P-gp inhibitors from natural products. Firstly, we constructed LVPs with high and low expression levels of P-gp. The LVPs can ensure the natural conformation of P-gp based on the principle that LVPs germinated from packaging cells will contain cell membrane fragments and P-gp they carry. Then the LVPs with high P-gp expression for active channel and LVPs with low P-gp expression for reference channel were immobilized on CM5 chip respectively. The affinity detection was thus carried out with the signal reduction on the two channels. The P-gp inhibitors, Valspodar (Val) and cyclosporin (CsA), as positive compounds, were detected to characterize the chip's activity, and the KD of Val and CsA were 14.09 µM and 16.41 µM, respectively. Forty compounds from natural product library were screened using the SPR CM5 chip, and magnolol (Mag), honokiol (Hon), and resveratrol (Res) were screened out as potential P-gp ligands, showing a significant response signal. This work presented a novel P-gp ligand screening system based on LVP-immobilized biosensor to rapidly screen out P-gp ligands from natural product library. Compared with traditional cell experiments which the screening time may take up to several days, our method only takes several hours. Furthermore, this study has also provided solid evidences to support that some complicated membrane proteins would apply to the lentivirus-based SPR screening system.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Técnicas Biossensoriais , Lentivirus/metabolismo , Ressonância de Plasmônio de Superfície , Animais , Produtos Biológicos , Compostos de Bifenilo/análise , Linhagem Celular Tumoral , Sobrevivência Celular , Química Farmacêutica/métodos , Ciclosporina/análise , Ciclosporinas/análise , Cães , Avaliação Pré-Clínica de Medicamentos/métodos , Células HEK293 , Humanos , Técnicas In Vitro , Cinética , Ligantes , Lignanas/análise , Células MCF-7 , Células Madin Darby de Rim Canino , Proteínas de Membrana/metabolismo , Resveratrol/análiseRESUMO
In the present study, we evaluated for the first time the variability of antioxidant traits of four Brassica wild species: B. incana, B. macrocarpa, B. villosa, and B. rupestris. The content of the main water-soluble antioxidants (phenolics, ascorbic acid, and total biothiols) and the in vitro antioxidant potential (1,1-diphenyl-2-picrylhydrazil (DPPH) and superoxide anion scavenging capacity) were investigated. A total of 28 polyphenolic compounds were identified by LC/MS and quantitated by HPLC/DAD analysis. Kaempferol and quercetin derivatives were the most abundant phenolics compared to hydroxycinnamoyl gentiobiosides. In the ten populations, phenolics ranged from 163.9 to 533.9 mg/100 g dry weight (d.w.), ascorbic acid from 7.6 to 375.8 mg/100 g d.w., and total biothiols from 0.59 to 5.13 mg/100 g d.w. The different classes of phytochemicals were separated using solid-phase extraction at increasing methanol concentrations, and the antioxidant power of fractionated extracts was evaluated. The superoxide anion scavenging activity was significantly correlated to phenolics, particularly to flavonol derivatives, while DPPH was mainly related to ascorbic acid content. The present findings improve the knowledge of the phytochemical composition of Italian Brassica wild species by showing the great diversity of phytochemicals among populations and highlighting their importance as a valuable genetic resource for developing new cultivars with improved bioactive content.
Assuntos
Antioxidantes/química , Brassica/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Antioxidantes/análise , Ácido Ascórbico/análise , Ácido Ascórbico/química , Compostos de Bifenilo/análise , Brassica/classificação , Cromatografia Líquida de Alta Pressão , Itália , Espectrometria de Massas , Compostos Fitoquímicos/análise , Picratos/análise , Extratos Vegetais/análise , Polifenóis/análise , Polifenóis/química , Sementes/química , SolubilidadeRESUMO
Propolis is a resinous bee hive product that has many biological activities. In this study, a total of 11 raw propolis samples were collected from various geographical areas in Turkey. Phenolic compounds were extracted from all samples and analyses of total phenolics and flavonoids and total antioxidant capacities were performed. All the samples showed high total phenolic and flavonoid contents and antioxidant capacities. Moreover, the in vitro bioaccessibility of Turkish propolis samples were investigated according to simulated in vitro gastrointestinal digestion method. Bioaccessibility was increased through the gastric and intestinal phases. Furthermore, the composition of polyphenols (phenolic acids and flavonoids) in Turkish propolis extracts was investigated by LC-MS/MS method. A total of 32 phenolic compounds, including Caffeic acid phenylethyl ester (CAPE) which was observed in all samples, were identified in the samples. Higher CAPE contents were determined in the samples from the Marmara region which is in line with its higher antioxidant capacity values. As a conclusion, propolis samples collected from different geographical locations differ for their phenolic and flavonoid contents, individual phenolic profile and bioaccessibility.
Assuntos
Antioxidantes/análise , Cromatografia Líquida , Fenóis/análise , Própole/química , Espectrometria de Massas em Tandem , Compostos de Bifenilo/análise , Digestão , Flavonoides/análise , Análise de Alimentos , Hidroxibenzoatos/análise , Modelos Biológicos , Picratos/análise , Polifenóis/análise , TurquiaRESUMO
Recently, new approaches for measuring antioxidant activity have been developed to eliminate or reduce the use of a spectrophotometer. All analytical methods must provide consistent and reliable results, which should be compared with statistical models. Therefore, we compared the conventional and dropping DPPH methods with three widely used standards. We employed and compared with three statistical methods. Good R-squared (R2â¯=â¯≥0.96) confirmed the similarity in comparison of using dropping DPPH method compared with the conventional DPPH method and reported lower deviations (ARDâ¯=â¯-0.32 to 0.13; RMSDâ¯=â¯0.10 to 1.15). Bland-Altman method (95% CI) demonstrated a good agreement between the two methods using standards and grape extracts (skin and seed). These findings suggested that the dropping DPPH method proved cheaper (without spectrophotometer) and correlated well with the conventional DPPH method. Therefore, this method could be affordably conducted in research laboratories in developing and less developed countries.
Assuntos
Antioxidantes/análise , Compostos de Bifenilo/análise , Modelos Estatísticos , Picratos/análise , Espectrofotometria/métodos , Antioxidantes/química , Compostos de Bifenilo/química , Cromatografia em Camada Fina , Picratos/químicaRESUMO
Traditional Tibetan medicine (TTM) has been valuable for the identification of new therapeutic leads. Nevertheless, reports about the chemical constituents of TTM are meager owing to the lack of suitable purification techniques. In this study, an off-line two-dimensional reversed-phase/hydrophilic interaction liquid chromatography (2D RP/HILIC) technique guided by on-line HPLC-DPPH has been established for the isolation of pure antioxidants from the extract of Dracocephalum heterophyllum. According to the chromatographic recognition outcome of the HPLC-DPPH system, the first-dimensional (1D) separation on the Megress C18 preparative column yielded 6 antioxidative fractions (61.4% recovery) from the ethyl acetate fraction (6.1â¯g). In the second-dimensional (2D) separation, a HILIC XAmide preparative column was employed. In total, 8 antioxidants were isolated from D. heterophyllum with a purity of >95%, which indicated the efficiency of the developed method to prepare antioxidative compounds with high purity from plant extracts. In addition, this method was highly efficient for the preparation of structural analogues of the antioxidative polyphenols and could be applied for the purification of structural analogues from other resources.
Assuntos
Antioxidantes/isolamento & purificação , Cromatografia de Fase Reversa/métodos , Lamiaceae/química , Extratos Vegetais/química , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/metabolismo , Compostos de Bifenilo/análise , Compostos de Bifenilo/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Interações Hidrofóbicas e Hidrofílicas , Picratos/análise , Picratos/metabolismoRESUMO
Different kinds of freshwater fish soups show a diverse range of health functions, due to their different nutritional substances and corresponding bioactivities. In the current study, in order to learn the theoretical basis of the potential role fish soup plays in diet therapy functions, the changes of nutrient profiles and antioxidant activities in crucian carp soup and snakehead soup (before and after simulated gastrointestinal digestion) were investigated, such as chemical composition, free amino acids, mineral and fatty acid contents, DPPH radical scavenging activity, ferrous ion chelating activity, hydroxyl radical-scavenging activity and the reducing power effect. Results show that the content of mineral elements in snakehead fish soup was significantly higher than that of crucian carp soup, especially for the contents of Ca, Zn, Fe. The content of total amino acid (TAA) of crucian carp soup (82.51 mg/100 mL) was much higher than that of snakehead fish soup (47.54 mg/100 mL) (p < 0.05). Furthermore, the antioxidant capacity of crucian carp soup was stronger than that of snakehead soup. The intensive profiles of nutritional composition and antioxidant activities of these two kinds of fish soups were expected to partly provide the theoretical basis of therapeutic effects.
Assuntos
Aminoácidos/análise , Antioxidantes/análise , Ácidos Graxos/análise , Animais , Compostos de Bifenilo/análise , Carpas , Digestão , Peixes , Análise de Alimentos/métodos , Picratos/análiseRESUMO
The enzyme sphingomyelinase (SMase) is an important biomarker for several diseases such as Niemann Pick's, atherosclerosis, multiple sclerosis, and HIV. We present a two-component colorimetric SMase activity assay that is more sensitive and much faster than currently available commercial assays. Herein, SMase-triggered release of cysteine from a sphingomyelin (SM)-based liposome formulation with 60 mol % cholesterol causes gold nanoparticle (AuNP) aggregation, enabling colorimetric detection of SMase activities as low as 0.02 mU/mL, corresponding to 1.4 pM concentration. While the lipid composition offers a stable, nonleaky liposome platform with minimal background signal, high specificity toward SMase avoids cross-reactivity of other similar phospholipases. Notably, use of an SM-based liposome formulation accurately mimics the natural in vivo substrate: the cell membrane. We studied the physical rearrangement process of the lipid membrane during SMase-mediated hydrolysis of SM to ceramide using small- and wide-angle X-ray scattering. A change in lipid phase from a liquid to gel state bilayer with increasing concentration of ceramide accounts for the observed increase in membrane permeability and consequent release of encapsulated cysteine. We further demonstrated the effectiveness of the sensor in colorimetric screening of small-molecule drug candidates, paving the way for the identification of novel SMase inhibitors in minutes. Taken together, the simplicity, speed, sensitivity, and naked-eye readout of this assay offer huge potential in point-of-care diagnostics and high-throughput drug screening.
Assuntos
Compostos de Bifenilo/análise , Colorimetria , Desipramina/análise , Inibidores Enzimáticos/análise , Naftalenos/análise , Pirimidinonas/análise , Esfingomielina Fosfodiesterase/análise , Animais , Compostos de Bifenilo/farmacologia , Bovinos , Desipramina/farmacologia , Inibidores Enzimáticos/farmacologia , Lipossomos/química , Estrutura Molecular , Naftalenos/farmacologia , Tamanho da Partícula , Pirimidinonas/farmacologia , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Esfingomielina Fosfodiesterase/metabolismo , Propriedades de SuperfícieRESUMO
Magnolia officinalis and Magnolia obovata bark extracts have been used for thousands of years in Chinese and Japanese traditional medicines and are still widely employed as herbal preparations for their sedative, antioxidant, anti-inflammatory, antibiotic, and antispastic effects. Neolignans, particularly magnolol and honokiol, are the main substances responsible for the beneficial properties of the magnolia bark extract (MBE). The content of magnolol and honokiol in MBE depends on different factors, including the Magnolia plant species, the area of origin, the part of the plant employed, and the method used to prepare the extract. The biological and pharmacological activities of magnolol and honokiol have been extensively investigated. Here we review the safety and toxicological properties of magnolol and honokiol as pure substances or as components of concentrated MBE, including the potential side-effects in humans after oral intake. In vitro and in vivo genotoxicity studies indicated that concentrated MBE has no mutagenic and genotoxic potential, while a subchronic study performed according to OECD (Organisation for Economic Co-operation and Development) guidelines established a no adverse effect level for concentrated MBE > 240 mg/kg b.w/d. Similar to other dietary polyphenols, magnolol and honokiol are subject to glucuronidation, and despite a relatively quick clearance, an interaction with pharmaceutical active principles or other herbal constituents cannot be excluded. However, intervention trials employing concentrated MBE for up to 1 y did not report adverse effects. In conclusion, over the recent years different food safety authorities evaluated magnolol and honokiol and considered them safe.
Assuntos
Compostos de Bifenilo/efeitos adversos , Compostos de Bifenilo/farmacocinética , Compostos de Bifenilo/toxicidade , Lignanas/efeitos adversos , Lignanas/farmacocinética , Lignanas/toxicidade , Animais , Compostos de Bifenilo/análise , Interações Medicamentosas , Humanos , Lignanas/análise , Magnolia/química , Testes de Mutagenicidade , Extratos Vegetais/química , Distribuição TecidualRESUMO
This paper reviews a selection of the most important studies on antioxidants in foods (including beverages), food ingredients, and dietary supplements by effect-directed analysis using TLC with DPPH*, ABTS*+, and ß-carotene direct bioautography. Total antioxidant activity by visible mode spectrometry (colorimetry) with TLC used offline to obtain additional analytical results, mostly for identification and quantification of phenolic compounds in samples, is also discussed. Finally, dot-blot assay for total antioxidant activity, carried out on a TLC plate without mobile-phase development, is reviewed as an alternative with possible advantages compared with spectrometry.
Assuntos
Antioxidantes/análise , Cromatografia em Camada Fina/métodos , Suplementos Nutricionais/análise , Análise de Alimentos/métodos , Ingredientes de Alimentos/análise , Animais , Bebidas/análise , Compostos de Bifenilo/análise , Colorimetria/métodos , Humanos , Espectrometria de Massas/métodos , Picratos/análise , beta Caroteno/análiseRESUMO
A simultaneous immunosensor based on surface plasmon resonance (SPR) was developed for determination of 3 pesticides -boscalid, clothianidin and nitenpyram- instead of the direct competitive enzyme-linked immunosorbent assays (dcELISAs) widely used as individual determination methods. Carboxy groups that introduced compounds to their pesticides were designed, and conjugates of them and bovine serum albumin were immobilized onto separate channels of the same sensor chip. When a mixture of 3 monoclonal antibodies reacted to each pesticide, and 3 pesticides were injected into the SPR immunosensor, each channel showed specific reactivity at 15 - 93 ng mL-1 for boscalid, 6.7 - 27 ng mL-1 for clothianidin, and 7.3 - 62 ng mL-1 for nitenpyram. Recovery tests using vegetables spiked with a mixture of 3 pesticides showed good results: 75 - 90%, 88 - 104%, and 72 - 105%, respectively, with a high correlation to results of the dcELISAs. The SPR immunosensor would be useful for the determination of pesticide residues in vegetables.
Assuntos
Compostos de Bifenilo/análise , Ensaio de Imunoadsorção Enzimática , Guanidinas/análise , Neonicotinoides/análise , Niacinamida/análogos & derivados , Resíduos de Praguicidas/análise , Tiazóis/análise , Verduras/química , Técnicas Biossensoriais , Estrutura Molecular , Niacinamida/análise , Ressonância de Plasmônio de SuperfícieRESUMO
Polyphenolic catechins prevalent in tea are powerful antioxidants for therapeutics of various free radical-related diseases. The non-epicatechins are thermally obtained from the naturally abundant epicatechins. In our study series on the structure-antioxidant property relationship of the CD inclusion complexes with tea catechins, this closing chapter presents the ß-CD encapsulation of three non-epicatechins, i.e., (-)-gallocatechin (GC) 1, (-)-catechin gallate (GC) 2, and (-)-gallocatechin gallate (GCG) 3 investigated by means of single-crystal X-ray diffraction, DFT calculation and DPPH radical scavenging activity assay. Detailed structural comparisons of the ß-CD inclusion complexes with both non-epi and epi type catechins reveal that a common host-guest hydrogen bonding scheme and the shielding of catechin OH groups inside the host circular wall play a prime role in flourishing antioxidant capacities in the order of 3â¯>â¯2â¯>â¯1. This is consistent with the relative thermodynamic stabilities derived from DFT energy minimization.
Assuntos
Antioxidantes/química , Compostos de Bifenilo/análise , Picratos/análise , Teoria Quântica , Chá/química , Raios X , beta-Ciclodextrinas/química , Estrutura MolecularRESUMO
Methylated vegetable oil adjuvants can enhance initial deposition and decrease the required dosages of pesticides sprayed on plants, so an oil adjuvant mixed with fungicides were used to prevent and control gray mold in greenhouse strawberry. As the persistence and dietary exposure risks from fungicides on strawberries after using adjuvants have not been assessed, the efficacy, dissipation and safety of pyrimethanil and boscalid in the presence and absence of a methylated vegetable oil adjuvant were evaluated. To better describe the actual use of fungicides in greenhouse strawberry, twice repeated application of fungicides were conducted follower by an optimized QuEChERS pre-treatment method. When applied at 60% of their recommended dosages with the adjuvant, the efficacy of pyrimethanil and boscalid for gray mold was similar to that shown by the treatment of 100% fungicides in absence of the adjuvant based on Duncan's Multiple-Range test, and their average residues increased to 89.0% and 89.3%, respectively. The adjuvant enhanced the accumulation effect of pyrimethanil residue by 31.7% after repeated applications, and the half-lives were similar (5.2 and 4.2 d). The adjuvant had comparable accumulation effects (1.75 and 1.83) and similar half-lives (5.4 and 5.5 d) for boscalid. In absence of adjuvant, the risk quotients (RQs) of pyrimethanil (0.41 and 0.33) and boscalid (0.49 and 0.63) after twice applications at pre-harvest interval were lower than 1. Adding the methylated vegetable oil adjuvant to fungicides would result in unprolonging half-life and acceptably low dietary exposure risk on strawberries, but lower dosage of fungicides were used.
Assuntos
Compostos de Bifenilo/administração & dosagem , Fragaria , Fungicidas Industriais/administração & dosagem , Niacinamida/análogos & derivados , Resíduos de Praguicidas/análise , Óleos de Plantas/administração & dosagem , Pirimidinas/administração & dosagem , Compostos de Bifenilo/análise , Botrytis/efeitos dos fármacos , Fragaria/química , Fragaria/microbiologia , Fungicidas Industriais/análise , Niacinamida/administração & dosagem , Niacinamida/análise , Doenças das Plantas/prevenção & controle , Óleos de Plantas/análise , Pirimidinas/análiseRESUMO
The aim of this work was to develop a programmable flow system for rapid assessment of total antioxidant capacity (TAC). Novel features of the prototype include a single pressure-driven source, versatile manipulation of fluid flows, ability to adapt to different TAC assays, and compatibility with microfluidic design. Antioxidant activity was determined by electrochemical measurement of residual 2,2-diphenyl-2-picrylhydrayl hydrate (DPPHâ¢) free radicals in the solution. The overall performance of the device was validated by the spectrophotometric method. The results indicated that dosing of reagents and samples could be controlled by pressure (R2 = 0.992) and time (R2 = 0.999) with high accuracy, and the mixing uniformity of the device was equivalent to that of the batch mixing (R2 = 0.994). TAC assays of a standard antioxidant, ascorbic acid, as well as selected samples such as orange and pomegranate juices, white wine, and green tea by the device were comparable to traditional measurement techniques. Due to the short incubation time, the approach may be more suitable for fast, rather than slow reacting antioxidant compounds. The developed system could be used for rapid TAC screening of food and biological samples.
Assuntos
Antioxidantes/análise , Compostos de Bifenilo/análise , Técnicas Eletroquímicas , Ensaios de Triagem em Larga Escala , Picratos/análise , Radicais Livres/análise , Sucos de Frutas e Vegetais/análise , Chá/química , Vinho/análiseRESUMO
The aim of the study was to identify new potential chemical markers of extra virgin olive oil (EVOO) quality by using a multicomponent analysis approach. Sixty-six EVOOs were purchased from the Italian market and classified according to their price as low price EVOOs (LEVOOs) and high price EVOOs (HEVOOs) costing 3.60-5.90euro/L and 7.49-29.80euro/L respectively. Sensory and chemical parameters strictly related to olive oil quality have been investigated, like volatile substances, polar phenolic substances, antioxidant activity, fatty acid composition, and α-tocopherol. Significant differences in terms of chemical composition and sensory features have been highlighted between the two EVOOs classes investigated, proving a generally lower level of quality of LEVOOs, clearly showed also by means of principal component analysis. Among the most interesting outcomes, R ratio (free tyrosol and hydroxytyrosol over total free and bound forms), measuring the extent of secoiridoids hydrolysis, resulted to be significantly higher in LEVOOs than in HEVOOs. Other key differences were found in the volatile substances composition, in the stearic acid percentage and in p-coumaric acid content.
Assuntos
Qualidade dos Alimentos , Azeite de Oliva/análise , Azeite de Oliva/química , Azeite de Oliva/economia , Aldeídos/análise , Antioxidantes/análise , Compostos de Bifenilo/análise , Ácidos Cumáricos/análise , Ácidos Graxos/análise , Humanos , Iridoides/análise , Itália , Olea/química , Azeite de Oliva/classificação , Fenóis/análise , Picratos/análise , Polifenóis/análise , Ácidos Esteáricos/análise , Tocoferóis/análise , alfa-Tocoferol/análiseRESUMO
An effective method to functionalize chitosan with 4-hexyloxyphenol (HP) under homogeneous reaction conditions was developed using laccase as the catalyst. The resulting copolymer was characterized for chemical structure, grafted-HP content, surface morphology, thermal stability, antioxidant capacity, hydrophobic properties and tensile strength. Solid-state 13C NMR spectrum confirmed the incorporation of HP onto chitosan. X-ray diffraction (XRD) showed a decrease in the degree of crystallinity for laccase/HP treated chitosan compared to pure chitosan. The grafted-HP content in laccase/HP-treated chitosan first increased and then declined with increase of the initial HP/chitosan ratio. A heterogeneous surface with spherical particles on the laccase/HP treated chitosan was observed by environmental scanning electron microscopy (ESEM) and scanning probe microscopy (SPM). The laccase/HP treatment of chitosan improved the thermal stability of copolymer. More significantly, the HP functionalized chitosan showed greatly improved ABTS+ and DPPH radicals scavenging capacity, compared with pure chitosan. The hydrophobicity property of the HP functionalized chitosan also significantly increased although its tensile strength decreased. This new type of composite with double functionalities (i.e., antioxidant and hydrophobic) could potentially be used as food packaging materials or coating agents.
Assuntos
Antioxidantes/química , Quitosana/química , Lacase/metabolismo , Éteres Fenílicos/química , Antioxidantes/metabolismo , Ascomicetos , Compostos de Bifenilo/análise , Compostos de Bifenilo/metabolismo , Quitosana/metabolismo , Proteínas Fúngicas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Éteres Fenílicos/metabolismo , Picratos/análise , Picratos/metabolismo , Propriedades de Superfície , Resistência à Tração , Difração de Raios XRESUMO
BACKGROUND: Juniperus communis L. represents a multi-purpose crop used in the pharmaceutical, food, and cosmetic industry. Several studies present the possible medicinal properties of different Juniperus taxa native to specific geographical area. The present study aims to evaluate the genoprotective, antioxidant, antifungal and anti-inflammatory potential of hydroalcoholic extract of wild-growing Juniperus communis L. (Cupressaceae) native to Romanian southern sub-Carpathian hills. METHODS: The prepared hydroethanolic extract of Juniperus communis L. was characterized by GC-MS, HPLC, UV-Vis spectrometry and phytochemical assays. The antioxidant potential was evaluated using the DPPH assay, the antifungal effect was studied on Aspergillus niger ATCC 15475 and Penicillium hirsutum ATCC 52323, while the genoprotective effect was evaluated using the Allium cepa assay. The anti-inflammatory effect was evaluated in two inflammation experimental models (dextran and kaolin) by plethysmometry. Male Wistar rats were treated by gavage with distilled water (negative control), the microemulsion (positive control), diclofenac sodium aqueous solution (reference) and microemulsions containing juniper extract (experimental group). The initial paw volume and the paw volumes at 1, 2, 3, 4, 5 and 24 h were measured. RESULTS: Total terpenoids, phenolics and flavonoids were estimated to be 13.44 ± 0.14 mg linalool equivalent, 19.23 ± 1.32 mg gallic acid equivalent, and 5109.6 ± 21.47 mg rutin equivalent per 100 g of extract, respectively. GC-MS characterization of the juniper extract identified 57 volatile compounds in the sample, while the HPLC analysis revealed the presence of the selected compounds (α-pinene, chlorogenic acid, rutin, apigenin, quercitin). The antioxidant potential of the crude extract was found to be 81.63 ± 0.38% (measured by the DPPH method). The results of the antifungal activity assay (for Aspergillus niger and Penicillium hirsutum) were 21.6 mm, respectively 17.2 mm as inhibition zone. Test results demonstrated the genoprotective potential of J. communis undiluted extract, inhibiting the mitodepressive effect of ethanol. The anti-inflammatory action of the juniper extract, administered as microemulsion in acute-dextran model was increased when compared to kaolin subacute inflammation induced model. CONCLUSION: The hydroalcoholic extract obtained from wild-growing Juniperus communis native to Romanian southern sub-Carpathian hills has genoprotective, antioxidant, antifungal and anti-inflammatory properties.