Rapid, simultaneous and non-destructive determination of multiple adulterants in Panax notoginseng powder by front-face total synchronous fluorescence spectroscopy.

The authentication of traditional herbal medicines in powder form is of great significance, as they are always of high values but vulnerable to adulteration. Based on the distinct fluorescence of protein tryptophan, phenolic acids and flavonoids, front-face synchronous fluorescence spectroscopy (FFSFS) was applied for the fast and non-invasive authentication of Panax notoginseng powder (PP) adulterated with the powder of rhizoma curcumae (CP), maize flour (MF) and whole wheat flour (WF). For either single or multiple adulterants in the range of 5-40% w/w, prediction models were built based on the combination of unfolded total synchronous fluorescence spectra and partial least square (PLS) regression, and were validated by both five-fold cross-validation and external validation.

Enhanced preservation effects of clove (Syzygium aromaticum) essential oil on the processing of Chinese bacon (preserved meat products) by beta cyclodextrin metal organic frameworks (β-CD-MOFs).

The applications of clove (Syzygium aromaticum) essential oil (CEO) are limited by instability, low solubility and high volatility. The present study aimed to improve the properties of CEO by microencapsulation with cyclodextrin metal organic frameworks (β-CD-MOFs) to enhance the preservation effects on Chinese bacon (preserved meat products). The microencapsulated CEO by β-CD-MOFs (CEO/β-CD-MOFs) not only did not inhibit the antioxidant activities of CEO, but also showed significant improvements on their ROS scavenging abilities and thermo-/pH-stabilities.

Comparative Analysis of Intracellular and Antioxidant Activities of Essential Oil From White and Black Pepper ( L.).

Pepper essential oils have potential immunomodulatory, anti-tumor, and anti-cancer activities. Pepper exhibits the potential to prevent or attenuate carcinogenesis as therapeutic tools. However, the related mechanism remains unelucidated.

Polyethylene mesh knitted fabrics mulching the soil to mitigate China's haze: A potential source of PBDEs.

The fate of polybrominated diphenyl ethers (PBDEs) from polyethylene mesh knitted fabrics (PMKFs) to mulched soil and nearby plants was studied. PBDEs in the soil sample collected from Tianjin University of Commerce in April 2019 increased significantly after 6 months of PMKF mulching owing to PMKFs as the main input source. The compositional profiles/congener patterns of the PBDEs in the soil and PMKFs became similar after 6 months.

Front-face synchronous fluorescence spectroscopy for rapid and non-destructive determination of free capsanthin, the predominant carotenoid in chili (Capsicum annuum L.) powders based on aggregation-induced emission.

Capsanthin is the major natural carotenoid pigment in red chili pepper possessing important bioactivity. Its conventional determination method is high performance liquid chromatography (HPLC) with complex and tedious sample pretreatment. In this study, synchronous front-face fluorescence spectroscopy (FFFS) was applied for the fast and non-invasive detection of free capsanthin in chili powders.

Comparing acaricidal and ovicidal activity of five terpenes from essential oils against Psoroptes cuniculi.

Essential oils and their components represent an appealing alternative strategy against parasitic mites. The chemical complexity and variability of essential oils limit their use and additional work is required to analyze the efficacy and application rate of essential oils' individual components. In the present study, the activity of five terpenes (terpinen-4-ol, citral, linalool, eugenol, and geraniol) was evaluated against Psoroptes cuniculi motile stages and eggs collected from naturally infected rabbits.

Effect of ethanol fumigation on pericarp browning associated with phenol metabolism, storage quality, and antioxidant systems of wampee fruit during cold storage.

Wampee fruit is a popular fruit cultivar in South-East Asia due to its high levels of nutrients and antioxidants; however, pericarp browning leads to a short storage life with great economic loss during years. The purpose of this work was to determine whether postharvest ethanol fumigation affected pericarp browning development of wampee fruit during 12 days of storage at 8 ± 0.5°C, and if so, how it is related to phenol metabolism and how it affects quality attributes and antioxidant systems during storage.

Improvement of the stabilities and antioxidant activities of polyphenols from the leaves of Chinese star anise (Illicium verum Hook. f.) using β-cyclodextrin-based metal-organic frameworks.

Background: Polyphenols extracted from plants are usually highly unstable and rapidly transformed into various reaction products during food and drug processing, thus limiting their applications. To improve the stability and solubility of polyphenols from the leaves of Chinese star anise (Illicium verum Hook. f.

Polyphenol oxidase plays a critical role in melanin formation in the fruit skin of persimmon (Diospyros kaki cv. 'Heishi').

In this study, the melanin in persimmon and its formation were investigated. Melanin was found to be deposited on the cell walls of the upper epidermis and subepidermal cells in persimmon skin and the isolated pigment appears to have lamellar structures. Diagnostic analysis of the isolated pigment showed results that were similar to those of melanin from other sources.

Antioxidant compound screening and chemical composition of sweet ginger (Alpinia coriandriodora D. Fang) essential oil and the mechanism of scavenging radicals.

The chemical components of an edible spice, sweet ginger (Alpinia coriandriodora D. Fang) essential oil (AEO) were identified by an ultra-fast gas chromatography electronic nose (E-nose) and the main components were β-pinene (27.9%), 1,8-cineole (17.

Antioxidant activity screening and chemical constituents of the essential oil from rosemary by ultra-fast GC electronic nose coupled with chemical methodology.

Background: Traditional chemical methods were mainly used to evaluate the total antioxidant activity of essential oils. How to determine the bioactivity of each compound in mixtures is an interesting research topic. Nowadays, an ultra-fast gas chromatography electronic nose (E-nose) has been gradually used in the detection of volatile compounds, but the screening of the active components of essential oils has not been reported.

One pot synthesis of water-soluble quercetin derived multifunctional nanoparticles with photothermal and antioxidation capabilities.

As a member of flavonoids, the application of quercetin has been mainly focused on antioxidation study. Fabrication of multifunctional nanoplatforms with quercetin is limited. In the present study, water-soluble quercetin derived nanoparticles (QFNPs) were fabricated through the one pot synthesis strategy with Fe, quercetin and poly (vinyl pyrrolidone) (PVP).

Antioxidant activity evaluation of rosemary ethanol extract and their cellular antioxidant activity toward HeLa cells.

Rosemary ethanol extract (REE) from Rosmarinus officinalis was identified by LC-ESI-MS/MS and 12 compounds were found. Among them, rosmarinic acid (389.78 μg/mg in REE), luteolin-3'-O-glucuronide (325.

Prediction of Hemodialysis Timing Based on LVW Feature Selection and Ensemble Learning.

We propose an improved model based on LVW embedded model feature extractor and ensemble learning for improving prediction accuracy of hemodialysis timing in this paper. Due to this drawback caused by feature extraction models, we adopt an enhanced LVW embedded model to search the feature subset by stochastic strategy, which can find the best feature combination that are most beneficial to learner performance. In the model application, we present an improved integrated learners for model fusion to reduce errors caused by overfitting problem of the single classifier.

The preservation effect of yeast on anthracnose of postharvest mango fruits and the possible mechanism.

This study aimed to determine the effects of yeast on storage quality of 'Tainong' mango, and elucidate it's possible anti-disease mechanism. The results showed that could inhibit the changes in peel colour, fruit firmness, the contents of total soluble solids, total acid and vitamin C, and maintain the storage quality of mango fruits. An investigation of the mechanism showed that competed not only for the primary carbon source, but also for living space with .

Screening and evaluation of active compounds in polyphenol mixtures by HPLC coupled with chemical methodology and its application.

An off-line high performance liquid chromatography (HPLC) coupled with chemical methods has been developed to evaluate antioxidant activity of 11 standard polyphenol compounds (SPCs) and vitamin C (Vc) in terms of radical scavenging abilities. The structure-activity relationships of each SPC were also discussed. SPCs showed different abilities in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-3-ethyl-benzthiazoline-6-sulphonate (ABTS) and hydroxyl (OH) free radicals.

Synchronous front-face fluorescence spectroscopy for authentication of the adulteration of edible vegetable oil with refined used frying oil.

Synchronous front-face fluorescence spectroscopy has been developed for the discrimination of used frying oil (UFO) from edible vegetable oil (EVO), the estimation of the using time of UFO, and the determination of the adulteration of EVO with UFO. Both the heating time of laboratory prepared UFO and the adulteration of EVO with UFO could be determined by partial least squares regression (PLSR). To simulate the EVO adulteration with UFO, for each kind of oil, fifty adulterated samples at the adulterant amounts range of 1-50% were prepared.

Chemometric classification of Chinese lager beers according to manufacturer based on data fusion of fluorescence, UV and visible spectroscopies.

We report an application of data fusion for chemometric classification of 135 canned samples of Chinese lager beers by manufacturer based on the combination of fluorescence, UV and visible spectroscopies. Right-angle synchronous fluorescence spectra (SFS) at three wavelength difference Δλ=30, 60 and 80 nm and visible spectra in the range 380-700 nm of undiluted beers were recorded. UV spectra in the range 240-400 nm of diluted beers were measured.

Flavonoids in Juglans regia L. leaves and evaluation of in vitro antioxidant activity via intracellular and chemical methods.

Flavonoids are rich in Juglans regia L. leaves. They have potent antioxidant properties, which have been related to regulating immune function and enhancing anticancer activity.

Discrimination of fresh fruit juices by a fluorescent sensor array for carboxylic acids based on molecularly imprinted titania.

Design of chemical sensor arrays that can discriminate real-world samples has been highly attractive in recent years. Herein a fluorescent indicator-displacement sensor array for discrimination of fresh fruit juices was developed. By coupling the unique high affinity of titania to electron-donating anions and the cross-reactivity of molecularly imprinted materials to structurally similar species, a small array was fabricated using only one rhodamine-based fluorescent dye and three synthesized materials.

Titania-based molecularly imprinted polymer for sulfonic acid dyes prepared by sol-gel method.

A novel titania-based molecularly imprinted polymer (MIP) was synthesized through sol-gel process with sunset yellow (Sun) as template, without use of functional monomer. MIP was used as a solid-phase extraction material for the isolation and enrichment of sulfonic acid dyes in beverages. The results showed that MIP exhibited better selectivity, higher recovery and adsorption capacity for the sulfonic acid dyes compared to the non-imprinted polymer (NIP).

[Chiral separation of benzamide antipsychotics and determination of their enantiomers by high performance liquid chromatography].

A new method of the chiral separation of three drugs such as sulpiride, amisulpride and mosapride was developed on the chiral stationary phase of amylose-tris-(5-chloro-2-methylphenylcarbamate) (ACMPC) by high performance liquid chromatography. The chromatographic behaviors of enantiomers of the three drugs were investigated in the mobile phases consisted of ethanol and n-hexane (containing 0.1% (v/v) diethylamine).

Polyphenolics composition of the leaves of Zanthoxylum bungeanum Maxim. grown in Hebei, China, and their radical scavenging activities.

High performance liquid chromatography coupled with tandem mass spectrometry with electrospray ionization and negative ion detection (HPLC-ESI-MS/MS) was used to identify the polyphenols from the leaves of a traditional vegetable and spice, Zanthoxylum bungeanum Maxim., in China by comparison of the retention times and mass spectral fragment with standard substances or related literature. A phenolic acid glucoside, two acids, and eight flavonoids were determined including vanillic acid-4-glucoside (22.

Complexation study of brilliant cresyl blue with beta-cyclodextrin and its derivatives by UV-vis and fluorospectrometry.

The complexation reactions of brilliant cresyl blue (BCB) with beta-cyclodextrin (beta-CD), mono[2-O-(2-hydroxypropyl)]-beta-CD (2-HP-beta-CD), mono[2-O-(2-hydroxyethyl)]-beta-CD (2-HE-beta-CD), and heptakis(2,6-di-methyl) -beta-CD (DM-beta-CD) were investigated using UV-vis and fluorospectrometry. The complexation between BCB and CDs could inhibit the aggregation of BCB molecules and could cause its absorbance at 634nm gradually increasing. The fluorescence of BCB was also enhanced with the addition of CDs.

Influence of solvation interactions on the zeta potential of titania powders.

The influence of solvation interactions on the surface charge of titania powders was studied by means of linear solvation energy relationships (LSER). The zeta potential (ZP) of titania powders and the effect of water content were determined in a series of alcohols, including methanol, ethanol, 1-propanol, isopropanol, and 1-butanol. The ZPs against the solvents' 13 LSER descriptors were analyzed by principal component analysis (PCA), cluster analysis, multiple linear regression (MLR), and stepwise multiple regression (SMR).