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991.
Ricardo Aguilar-Villalva Gustavo A. Molina Beatriz Liliana España-Sánchez Luis Fernando Díaz-Peña Alberto Elizalde-Mata Edgar Valerio Cristy Azanza-Ricardo Miriam Estevez 《Arabian Journal of Chemistry》2021,14(7):103239
In recent years, the food, pharmacy, and cosmetic industries have focused on the search of natural compounds with antimicrobial and antioxidant properties; commonly, these compounds are obtained from Kingdom plantae. The aim of the present work is comparing antibacterial and antioxidant capacity of Annona cherimola Mill leaves, using different extraction methods. The ultrasound assisted extraction technique (UAE) was compared with conventional techniques: Soxhlet and maceration. Water and ethanol were used as solvents for leaves extractions performed with these three methods. The main acetogenins reported in Annona cherimola Mill and Annona muricata L. species were simulated using the functional hybrid B3LYP and to confirm its presence, analysis of the compound composition was performed using FT-IR, UV–Vis and HPLC. Total phenolics (TP) and flavonoids (TF) were determined by spectroscopy techniques and novel Differential Pulse Voltammetry (DPV) electrochemical technique. Total Antioxidant Capacity (TAC) of the extracts was measured, using the DPPH, FRAP and CUPRAC techniques. The highest antioxidant content was found in the Soxhlet water extracts; even so, the UAE technique presented an attractive alternative due to considerable reduction in extraction time, which was greater than 99%, and possible selectivity in compounds extraction. Finally, antibacterial activity of the extracts was evaluated, obtaining the best results against gram-positive bacteria using UAE water extract. In this way, the UAE technique presents an excellent extraction option due to the considerable reduction in time and energy, as well as the increase in antibacterial activity. 相似文献
992.
993.
Ruihong Li Ziming Xia Bin Li Ying Tian Guangjie Zhang Min Li Junxing Dong 《Molecules (Basel, Switzerland)》2021,26(13)
Ginkgo biloba L. has always been a popular area of research due to its various active ingredients and pharmacological effects. Ginkgo biloba is rich in ginkgo flavonoids, ginkgolides, and ginkgolic acid, with anti-inflammation, antioxidation, neuroprotection, anti-platelet agglutination, hypolipidemic effect, anti-cancer, and anti-radiation properties. There are many methods to extract and separate the active components of ginkgo. Among them, supercritical carbon dioxide fluid extraction (SFE-CO2) is known for its green, clean, and environment-friendly properties. In this paper, the pharmacological activities, the active components, and structures of different parts of ginkgo, the extraction methods of its effective ingredients, and the application of the SFE-CO2 method for the extraction and separation of active ingredients in Ginkgo biloba from leaves, seeds, pollen, and roots were reviewed, in order to make best use of ginkgo resources, and provide support and references for the development of SFE-CO2 of active components from Ginkgo biloba. 相似文献
994.
Aurel Diacon Ioan Clinescu Mircea Vinatoru Petre Chipurici Alexandru Vlaicu Aurelian Cristian Boscornea Timothy J. Mason 《Molecules (Basel, Switzerland)》2021,26(14)
Currently there is a drive towards the minimisation and reclamation of valuable materials from the waste products of the food and beverage industry. This can be achieved through the extraction of residual nutraceuticals from such materials. Tomato pomace contains carotenoids and other chemicals which can be extracted directly into edible oils to improve the health-giving properties of such oils. We report here a novel green solvent, fatty acid ethyl esters (FAEE), which is significantly more effective than sunflower oil and hexane for the extraction of lycopene and beta-carotene from tomato skin waste. FAEE are a non-toxic renewable resource that is environmentally friendly and to our knowledge has never been used as a vegetal extraction fluid. The efficiency of FAEE extraction was significantly improved relative to both sunflower oil and hexane under ultrasound-assisted extraction (UAE) conditions. In addition, FAEE have the additional and significant advantage that once enriched with the extracted nutraceuticals can be used directly as a food additive. 相似文献
995.
Valentina Noemi Madia Daniela De Vita Davide Ialongo Valeria Tudino Alessandro De Leo Luigi Scipione Roberto Di Santo Roberta Costi Antonella Messore 《Molecules (Basel, Switzerland)》2021,26(15)
Growing attention to environmental protection leads food industries to adopt a model of “circular economy” applying safe and sustainable technologies to recover, recycle and valorize by-products. Therefore, by-products become raw material for other industries. Tomato processing industry produces significant amounts of by-products, consisting of skins and seeds. Tomato skin is very rich in lycopene, and from its seeds, high nutritional oil can be extracted. Alternative use of the two fractions not only could cut disposal costs but also allow one to extract bioactive compounds and an oil with a high nutritional value. This review focused on the recent advance in extraction of lycopene, whose beneficial effects on health are widely recognized. 相似文献
996.
Dounia Elfadil Abderrahman Lamaoui Flavio Della Pelle Aziz Amine Dario Compagnone 《Molecules (Basel, Switzerland)》2021,26(15)
Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given. 相似文献
997.
Ana Margarida Silva Diana Pinto Iva Fernandes Victor de Freitas María de la Luz Cdiz-Gurrea Paulo Costa Cristina Delerue-Matos Francisca Rodrigues 《Molecules (Basel, Switzerland)》2021,26(8)
During kiwiberry production, different by-products are generated, including leaves that are removed to increase the fruit’s solar exposure. The aim of this work was to extract bioactive compounds from kiwiberry leaf by employing microwave-assisted extraction (MAE). Compatible food solvents (water and ethanol) were employed. The alcoholic extract contained the highest phenolic and flavonoid contents (629.48 mg of gallic acid equivalents (GAE) per gram of plant material on dry weight (dw) (GAE/g dw) and 136.81 mg of catechin equivalents per gram of plant material on dw (CAE/g dw), respectively). Oppositely, the hydroalcoholic extract achieved the highest antioxidant activity and scavenging activity against reactive oxygen and nitrogen species (IC50 = 29.10 μg/mL for O2•−, IC50 = 1.87 μg/mL for HOCl and IC50 = 1.18 μg/mL for •NO). The phenolic profile showed the presence of caffeoylquinic acids, proanthocyanidin, and quercetin in all samples. However, caffeoylquinic acids and quercetin were detected in higher amounts in the alcoholic extract, while proanthocyanidins were prevalent in the hydroalcoholic extract. No adverse effects were observed on Caco-2 viability, while the highest concentration (1000 µg/mL) of hydroalcoholic and alcoholic extracts conducted to a decrease of HT29-MTX viability. These results highlight the MAE potentialities to extract bioactive compounds from kiwiberry leaf. 相似文献
998.
Yassine Benmassaoud Khaled Murtada Rachid Salghi Mohammed Zougagh ngel Ríos 《Molecules (Basel, Switzerland)》2021,26(9)
In this study, we combine magnetic solid phase extraction (MSPE), with the screen-printed carbon electrode (SPCE) modified by a molecular imprinted polymer (MIP) for sensitive and selective extraction and electrochemical determination of Rhodamine B in food samples. A magnetic solid phase extraction (MSPE) was carried out using magnetic poly(styrene-co-divinylbenzene) (PS-DVB) and magnetic nanoparticles (MNPs) synthetized on the surface of multiwalled carbon nanotubes (MWCNTs). An MIP was prepared on the surface of MWCNTs in the presence of titanium oxide nanoparticles (TiO2NPs) modifying the SPCE for the rapid electrochemical detection of Rhodamine B. The MIPs synthesis was optimized by varying the activated titanium oxide (TiO2) and multiwalled carbon nanotubes (MWCNTs) amounts. The MSPE and electrochemical detection conditions were optimized as well. The present method exhibited good selectivity, high sensitivity, and good reproducibility towards the determination of Rhodamine B, making it a suitable method for the determination of Rhodamine B in food samples. 相似文献
999.
HU Tao YANG Weiwei WANG Cheng BU Yali JIN Feng ZHANG Dongwen GU Min LIU Wenhui LIANG Qinghua LIU Ruiqing FENG Xiaomiao MA Yanwen 《高等学校化学研究》2021,37(2):286-292
Sodiumion batteries(SIBs)have attracted intensive attention as promising alternative to lithium-ionbatteries(LIBs)for large scale energy storage systems because of low cost of sodium,similar energy storage mechanism and the reasonable performance.However,it is still a great challenge to search and design a robust structure of anode materials with excellent cycling stability and high rate capability for SIBs.Herein,multilayer porous vanadium nitride(VN)microsheets are synthesized through a facile and scalable hydrothermal synthesis-nitrogenization strategy as an effective anode material for SIBs.The multilayer porous VN microsheets not only offer more active sites for fast Na+insertion/extraction process and short diffusion pathway,but also effectively buffer the volume change of anode due to more space in the multilayer porous structure.The large proportions of capacitive behavior imply that the Na+charge storage depends on the intercalation pseudocapacitive mechanism.The multilayer porous VN microsheets electrodes manifest excellent cycling stability and rate capability,delivering a discharge capacity of 156.1 mA·h/g at 200 mA/g after 100 cycles,and a discharge capacity of 111.9 mA·h/g at 1.0 A/g even after 2300 cycles with the Coulombic efficiency of nearly 100%. 相似文献
1000.
《印度化学会志》2021,98(10):100142
A simple and low cost method for extraction and preconcentration of Arsenazo-III (ARS-III) and Magdala Red (MR) was developed by an efficient cloud point extraction (CPE) method using mixed micelles of Triton X–114 (TX–114) and cetyltrimethyl ammonium bromide (CTAB). Various parameters, such as pH/concentration of H2SO4, surfactant concentrations (TX-114 and CTAB), equilibrium temperature and time have been studied to maximise efficiency. Thermodynamic quantities like change in Gibbs free energy (ΔG0), change in enthalpy (ΔH0) and change in entropy (ΔS0) were calculated. The results show that the CPE of ARS-III and MR dye is feasible, spontaneous, and endothermic in the temperature range of (50–80) °C indicating good recoveries for the developed method. The effect of temperature, surfactant concentration and dye concentration on various thermodynamic quantities was investigated and it was found that ΔG0 values increased with temperature but decreased with surfactant and dye concentration. ΔH0 and ΔS0 values increased as surfactant concentration increased and decreased as dye concentration decreased. The recoveries were found to be the range from 90.02 – 101.03 % for ARS-III and 86.07–99.46 % for MR dyes which proves that the method is highly efficient. 相似文献