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91.
《印度化学会志》2021,98(11):100178
The extraction is a simple process and it is widely used to extract the fragrances in fragrance industries from essential oils. There are number of compounds (i.e. flowers, oils, leaves etc.) from which we can prepare the fragrance by extracting the essential oils from them. In this work, we have prepared the fragrance from the essential oils by the liquid-liquid extraction process, where the essential oil presented as the concentrated hydrophobic liquid containing volatile aroma compounds. We used the combination of Gas chromatography and Mass spectrometry (GC/MS) characterization techniques to make our product more useful, convenient and compitative with the other fragrance available in the market. This study would be helpful to understand the preparation of the fragrance from the concentrated hydrophobic liquid type essential oils which contains volatile aroma compounds by using a significant liquid-liquid extraction process.  相似文献   
92.
The biological activity of apple pectin extracted conventionally or enzymatically using endo-xylanase and endo-cellulase, was tested in vitro. The analyses were performerd in tetraplicates and the statistical significance of the differences were assessed using ANOVA, Tukey post hoc and LSD (the least significant difference) tests. Multivariate regression analysis was applied to determine the structural components that have a crucial importance for antioxidant and antitumor properties of pectins. The pectins extracted by enzymes contained up to four times more ferulic acid and showed twice as great ability to neutralize free radicals and Fe(III) reduction. The antiradical potential positively correlated with phenols, fucose and rhamnose content. In the assays performed on HT-29 human adenocarcinoma and B16F10 melanoma cell cultures, the “green” pectins, contrary to acid isolated ones, exhibited remarkable anti-neoplastic potential while being nontoxic to nontransformed L929 cell line. The pectins in the dose of 1 mg/mL were capable of inhibiting adhesion (max 23.1%), proliferation (max 40.4%), invasion (max 76.9%) and anchorage-independent growth (max 90%) of HT-29 cells (significance level p < 0.001). These pectin preparations were slightly less active towards B16F10 cells. The enzyme-isolated apple pectins may be useful as a functional food additive and an ingredient of the ointment formulas for post-surgical melanoma treatment.  相似文献   
93.
建立了一种机械力化学提取法和实时直接分析质谱(DART-MS)分析相结合的中草药多糖分析方法,同时测定了黄芪、银耳、百合、茯苓、鼓槌石斛、金钗石斛、铁皮石斛和党参8种中草药多糖。比较了机械力化学提取(MCE)法与传统方法的提取效果,并优化了MCE法的提取参数。通过体积排阻色谱分离中草药多糖,建立分子质量校准曲线,估算了多糖分子质量。利用DART-MS直接裂解多糖大分子,可瞬时获得m/z<350的碎片离子,不同的中草药多糖得到的特征性的质谱离子峰可用于多糖样品的有效区分。该方法具有简单、快速、高通量、无需预消化的特点,是直接从复杂多糖大分子中获取特征指纹图谱的有力工具。  相似文献   
94.
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   
95.
The ability to achieve high areal capacitance for oxide-based supercapacitor electrodes with high active mass loadings is critical for practical applications. This paper reports the feasibility of the fabrication of Mn3O4-multiwalled carbon nanotube (MWCNT) composites by the new salting-out method, which allows direct particle transfer from an aqueous synthesis medium to a 2-propanol suspension for the fabrication of advanced Mn3O4-MWCNT electrodes for supercapacitors. The electrodes show enhanced capacitive performance at high active mass loading due to reduced particle agglomeration and enhanced mixing of the Mn3O4 particles and conductive MWCNT additives. The strategy is based on the multifunctional properties of octanohydroxamic acid, which is used as a capping and dispersing agent for Mn3O4 synthesis and an extractor for particle transfer to the electrode processing medium. Electrochemical studies show that high areal capacitance is achieved at low electrode resistance. The electrodes with an active mass of 40.1 mg cm−2 show a capacitance of 4.3 F cm−2 at a scan rate of 2 mV s−1. Electron microscopy studies reveal changes in electrode microstructure during charge-discharge cycling, which can explain the increase in capacitance. The salting-out method is promising for the development of advanced nanocomposites for energy storage in supercapacitors.  相似文献   
96.
Orange pomace (OP) is a solid waste produced in bulk as a byproduct of the orange juice industry and accounts for approximately 50% of the quantity of the fruits processed into juice. In numerous literature references there is information about diverse uses of orange pomace for the production of high-added-value products including production of natural antioxidant and antimicrobial extracts rich in polyphenols and flavonoids which can substitute the hazardous chemical antioxidants/antimicrobials used in agro-food and cosmetics sectors. In this work and for the first time, according to our knowledge, the eco-friendly aqueous vacuum microwave assisted extraction of orange pomace was investigated and optimized at real industrial scale in order to produce aqueous antioxidant/antimicrobial extracts. A Response Surface Optimization methodology with a multipoint historical data experimental design was employed to obtain the optimal values of the process parameters in order to achieve the maximum rates of extraction of OP total polyphenols and/or total flavonoids for economically optimum production at industrial scale. The three factors used for the optimization were: (a) microwave power (b) water to raw pomace ratio and (c) extraction time. Moreover, the effectiveness and statistical soundness of the derived cubic polynomial predictive models were verified by ANOVA.  相似文献   
97.
Our experiments may help to answer the question of whether cowslip (Primula veris L.) is a rich source of bioactive substances that can be obtained by efficient extraction with potential use as a food additive. A hypothesis assumed that the type of solvent used for plant extraction and the individual morphological parts of Primula veris L. used for the preparation of herbal extracts will have key impacts on the efficiency of the extraction of bioactive compounds, and thus, the health-promoting quality of plant concentrates produced. Most analysis of such polyphenolic compound contents in extracts from Primula veris L. has been performed by using chromatography methods such as ultra-performance reverse-phase liquid chromatography (UPLC−PDA−MS/MS). Experiments demonstrated that the most effective extraction agent for fresh study material was water at 100 °C, whereas for dried material it was 70% ethanol. The richest sources of polyphenolic compounds were found in cowslip primrose flowers and leaves. The aqueous and ethanol extracts from Primula veris L. were characterized by a quantitatively rich profile of polyphenolic substances, and a high antioxidative potential. Selective extraction with the use of mild conditions and neutral solvents is the first step to obtaining preparations from cowslip primrose with a high content of bioactive substances.  相似文献   
98.
The disposal of food waste is a current and pressing issue, urging novel solutions to implement sustainable waste management practices. Fish leftovers and their processing byproducts represent a significant portion of the original fish, and their disposal has a high environmental and economic impact. The utilization of waste as raw materials for the production of different classes of biofuels and high-value chemicals, a concept known as “biorefinery”, is gaining interest in a vision of circular economy and zero waste policies. In this context, an interesting route of valorization is the extraction of omega-3 fatty acids (ω-3 FAs) for nutraceutical application. These fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have received attention over the last decades due to their beneficial effects on human health. Their sustainable production is a key process for matching the increased market demand while reducing the pressure on marine ecosystems and lowering the impact of waste production. The high resale value of the products makes this waste a powerful tool that simultaneously protects the environment and benefits the global economy. This review aims to provide a complete overview of the sustainable exploitation of fish waste to recover ω-3 FAs for food supplement applications, covering composition, storage, and processing of the raw material.  相似文献   
99.
Deep eutectic solvents (DESs) are green organic solvents that have broad prospects in the extraction of effective components of traditional Chinese medicine. This work employed the quantitative analysis of multi-components by a single marker (QAMS) method to quantitatively determine the six effective components of glycyrrhizic acid, liquiritin, isoliquiritin apioside, liquiritigenin, isoliquiritin, and glycyrrhetinic acid in Glycyrrhiza uralensis, which was used for comprehensive evaluation of the optimal extraction process by DESs. First, Choline Chloride: Lactic Acid (ChCl-LA, molar ratio 1:1) was selected as the most suitable DES by comparing the extraction yields of different DESs. Second, the extraction protocol was investigated by extraction time, extraction temperature, liquid-to-material ratio, molar ratio, and ultrasonic power. The Box–Behnken design (BBD) combined with response surface methodology (RSM) was used to investigate the optimal DES conditions. The result showed that the best DES system was 1.3-butanediol/choline chloride (ChCl) with the molar ratio of 4:1. The optimal extraction process of licorice was 20 mL/g, the water content was 30%, and the extraction time was 41 min. The comprehensive impact factor (z) was 0.92. At the same time, it was found that the microstructure of the residue extracted by the eutectic solvent was more severely damaged than the residue after the traditional solvent extraction through observation under an electron microscope. The DES has the characteristics of high efficiency and rapidity as an extraction solution.  相似文献   
100.
The consumers’ interest towards beer consumption has been on the rise during the past decade: new approaches and ingredients get tested, expanding the traditional recipe for brewing beer. As a consequence, the field of “beeromics” has also been constantly growing, as well as the demand for quick and exhaustive analytical methods. In this study, we propose a combination of nuclear magnetic resonance (NMR) spectroscopy and chemometrics to characterize beer. 1H-NMR spectra were collected and then analyzed using chemometric tools. An interval-based approach was applied to extract chemical features from the spectra to build a dataset of resolved relative concentrations. One aim of this work was to compare the results obtained using the full spectrum and the resolved approach: with a reasonable amount of time needed to obtain the resolved dataset, we show that the resolved information is comparable with the full spectrum information, but interpretability is greatly improved.  相似文献   
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