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AbstractTheaflavins, a major kind of component in black tea, have been reported to show a variety of biological activities and health effects. However, the unstable chemical properties, low bioavailability and unclear metabolism pathways of theaflavins have left much to be desired in terms of its specific efficacy and applications. This paper provides a comprehensive knowledge on the digestion, absorption, metabolism, distribution and excretion of theaflavins. We find that pH-dependent stability, efflux transport proteins are closely related to the low absorption rate and low bioavailability of theaflavins. When pass through the gastrointestinal tract, TFDG, TF2A and TF2B are gradually degraded to TF1, and release gallic acid. Then, the theaflavins skeleton are degraded into small molecular phenolic substances under the action of enzymes and microorganisms. In addition, theaflavins are widely distributed in the human body including brain, lung, heart, kidney, liver, blood tissue in a low content and can be excreted through feces. However, the influence of digestive enzymes barrier and gut microbial barrier on theaflavins are still unclear. Importantly, most findings are reported by in vitro methods and animal experiments, the metabolites and metabolic pathways of theaflavins in human body are not fully understood and need to be further investigated. We hope to lay a theoretical basis for exploring methods to improve the bioavailability of theaflavins and expanding the application of theaflavins in health foods as well as pharmaceuticals. [ABSTRACT FROM AUTHOR]

• We speculate the intestinal homeostasis underlie the antiaging effect of acteoside. • Acteoside palliates cognitive impairment by regulating intestinal homeostasis. • Antibiotic-induced microbiome depletion study confirmed the hypothesis. Acteoside, an important phenylethanol glycoside, is the main active component in Osmanthus fragrans flower. Our previous study found that acteoside showed high antiaging effect but its absorption rate was low. We speculated acteoside palliated aging-related cognitive impairment before being absorbed, that was intestinal homeostasis underlie the antiaging effect of acteoside. In this study, acteoside was confirmed to palliate cognitive impairment in d -galactose induced aging mice. Acteoside treatment dramatically reduced oxidative stress, alleviated intestinal inflammation, restored intestinal mucosal barrier, rebuilt gut microbiome structure and upregulated gut microbiome metabolites short-chain fatty acids (SCFAs) and amino acids (AAs). Furthermore, antibiotic treatment revealed that the antiaging ability of acteoside was abolished in microbiota depleted mice, which offered direct evidence for the essential role of gut microbiota in the attenuation of cognitive impairment of acteoside. Together, our study indicated that acteoside palliated cognitive impairment by regulating intestinal homeostasisand acteoside intake might be a promising nutritional intervention in prevention of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Acteoside has been reported to have antioxidant and neuroprotective effect, which is a promising therapeutic way in prevention and treatment of Parkinson's disease. The present study was aimed to understand the neuroprotective effect of acteoside and to elucidate its underlying mechanism. 6-hydroxydopamine (6-OHDA)-induced neural damage in zebrafish model was used to study the protective effect of acteoside on Parkinson's disease (PD). Locomotion behavioral test showed that acteoside could prevent 6-OHDA-stimulated movement disorders. Anti-tyrosine hydroxylase (TH) whole-mount immunostaining analysis showed that acteoside could prevent 6-OHDA-induced dopaminergic neuron death. In addition, pretreatment with acteoside could upregulate antioxidative enzymes by activating the Nrf2/ARE signaling pathway in zebrafish. Meanwhile, acteoside was found to be distributed in the brain after intraperitoneal injection into the adult zebrafish, indicating that this compound could penetrate the blood-brain-barrier (BBB). This study demonstrated that acteoside could penetrate BBB and have potential therapeutic value for PD by activating the Nrf2/ARE signaling pathway and attenuating the oxidative stress. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of metal ions on the degradation of phytosterols in oils. The oil was heated at 180 °C for 1 h with/without addition of Fe 3 + , Fe 2 + , Cu 2 + , Mn 2 + , Zn 2 + , Na + , Al 3 + and Mg 2 + . Variations of β-sitosterol, stigmasterol, campesterol, brassicasterol and their degradation products were confirmed by the GC–MS analysis. In general, the increase of the metal ion concentration resulted in more phytosterol degradation, and the ability of metal ions following decreasing order: Fe 3 + > Fe 2 + > Mn 2 + ≥ Cu 2 + ≥ Zn 2 + > Na + ≥ Mg 2 + > Al 3 + . Metal ions significantly induced phytosterol autoxidation on C5, C6 and C7 on Ring B of steroid nucleus at even a low concentration, and induced dehydration on the C3 hydroxyl to form dienes and trienes at high concentration. The metal ions in oils are accounted for increasing phytosterol degradation, which decreases food nutritional quality and gives rise to the formation of undesirable compounds. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Osmanthus fragrans var. thunbergii ( O. fragrans ) flower has been consumed as folk medicine for thousands of years. O. fragrans flower extract is a well-characterized phenylethanoid glycoside-rich extract, which has been used as a natural anti-oxidant. The aim of this study was to evaluate the safety of O. fragrans flower phenylethanoid glycoside-rich extract (OFFE). Materials and methods The OFFE was extracted by 80% (v/v) aqueous ethanol with 0.01% sodium isoascorbate (w/v) from the O. fragrans flower and purified on HPD300 resins. The total phenylethanoid glycosides content and individual phenylethanoid glycosides was determined by photocolorimetric method and reversed phase UPLC respectively. An acute oral toxicity study, reverse mutation test, bone marrow cell micronucleus test, and sperm abnormality test as well as a 90-day oral toxicity study were performed on experimental animals. Results The total content of phenylethanoid glycosides in OFFE was 73.4 g acteoside equivalent per 100 g of extract, include acteoside (52.5 g per 100 g of extract), salidroside (13.8 g per 100 g of extract), and isoacteoside (2.6 g per 100 g of extract) and so on. No acute lethal effect at the maximal tested OFFE dose of 10 g/kg body weight (bw) in either rats or mice was observed, suggesting that OFFE can be considered nontoxic. No evidence for mutagenicity was detected in any of the three mutagenic tests. Administration at levels of 0.50, 1.00, and 2.00 g/kg bw to rats for 90 days failed to induce any significant hematological, clinical, chemical, or histopathological changes. The no-observed adverse-effect-level for OFFE was >2.00 g/kg bw for the study on subchronic toxicity. Conclusion The results showed that consuming OFFE has no adverse effects and poses no health risk in the acute oral toxicity study, subchronic oral toxicity study, and in the micronucleus test, which may provide supportive evidence for the safety of OFFE powder that has been used in medicine as well as in functional foods, and dietary supplements. [ABSTRACT FROM AUTHOR]

Theaflavins (TFs) are a kind of bioactive compound that formed during the fermentation stage of black tea. TFs play a vital role both in the sensory quality and the biological activity of black tea. However, the complex composition of black tea and the low content of TFs in black tea (0.3%–0.7%) make the technology for the preparation of high‐purity TFs a great challenge. This review provides an updated overview for extracting, synthesizing and purifying of TFs. Molecular imprinting technology, an efficient method for extracting bioactive compounds, will be a promising method for the preparation of TFs with high purity. Overall, this review can provide a scientific basis and technical support for the preparation of TFs with high purity and will be helpful for the in‐depth development and further research of TFs. [ABSTRACT FROM AUTHOR]

Our present knowledge about the efficacy of tea consumption in improving age-related cognitive disorders is incomplete since previous epidemiological studies provide inconsistent evidence. This unified systematic review and meta-analysis based on updated epidemiological cohort studies and randomized controlled trials (RCTs) evidence aimed to overcome the limitations of previous reviews by examining the efficacy of distinct types of tea consumption. PubMed, Embase, and MEDLINE were searched up to May 20, 2022, and 23 cohorts and 12 cross-sectional studies were included. Random-effects meta-analyses were conducted to obtain pooled RRs or mean differences with 95% CIs. The pooled RRs of the highest versus lowest tea consumption categories were 0.81 (95% CIs: 0.75–0.88) and 0.69 (95% CIs: 0.61–0.77), respectively. The pooled mean difference of four included RCTs revealed a beneficial effect of tea on cognitive dysfunction (MMSE ES: 1.03; 95% CI, 0.14–1.92). Subgroup analyses further demonstrated that green and black tea intake was associated with a lower risk of cognitive disorders in eastern countries, especially in women. The evidence quality was generally low to moderate. The present review provides insight into whether habitual tea consumption can be an effective approach against age-related neurodegenerative cognitive disorders and summarizes potential mechanisms based on currently published literature. [ABSTRACT FROM AUTHOR]

A highly sensitive Surface Plasmon Resonance (SPR) sensor coupled magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) was developed and validated for the determination of 6-benzylaminopurine (6-BA) in vegetables. MMIPs NPs were synthesized using methacrylic acid (MAA) and sodium p-styrene sulfonate (SSS) as functional monomers. The SPR exhibited a linear dependence on 6-BA concentration in the range 5–300 pg/mL with a low limit of detection (3.02 pg/mL) and limit of quantitation (10.08 pg/mL). The SPR signal of 6-BA-captured MAA/SSS-MMIPs NPs is higher than those of the structural analogues (6-KT and 2-IP: 1.72 and 2.12 times) and the non-structural analogues (2, 4-D and NAA: 2.31 and 2.57 times), indicating the SPR sensor has good selectivity for 6-BA. The recovery of the established method was between 93.8% and 108.6% with a coefficient of variation less than 9.2% in four vegetables. This SPR sensor shows great potential in detecting 6-BA in more vegetables. Schematic diagram of the SPR sensor for the highly sensitive analysis of 6-benzylaminopurine(6- BA)based on bifunctional magnetic molecular imprinted polymers nanoparticles (MAA/SSS-MMIPs NPs). The MAA/SSS-MMIPs NPs could be simultaneously employed for the enrich and separate 6-BA in vegetables and the amplification of SPR signal due to their selective adsorption capacity, paramagnetism and large refractive index. The 6-BA in vegetables samples can be selectively extracted and enriched by MAA/SSS-MMIPs NPs, which significantly eliminates the sample matrix interference. The SPR sensor detection is achieved due to the adsorption of 6-BA-captured MAA/SSS-MMIPs NPs on the chip surface by means of the electrostatic interaction with 3-Mercaptopropionic Acid (3-MPA). The developed SPR sensor shows advantages of the low cost with the simplicity of detection method and allows to quantitative determination of 6-BA with a low limit of detection (LOD) 3.02 pg/mL. Further, the practicability of the SPR sensor was demonstrated in the quantification of the 6-BA in real vegetable samples. [Display omitted] • SPR sensor with MAA/SSS-MMIPs NPs was developed for highly sensitive 6-BA detection. • MAA/SSS-MMIPs NPs were simultaneously used to extract 6-BA and enhance SPR signal. • The 6-BA could be detected with the LOD of 3.02 pg/mL and LOQ of 10.08 pg/mL. • The SPR sensor was applied to detect 6-BA in vegetables with good accuracy [ABSTRACT FROM AUTHOR]

Various phytochemicals have been reported to protect against oxidative stress. However, the mechanism underlying has not been systematically evaluated, which limited their application in disease treatment. Nuclear factor erythroid 2−related factor 2 (Nrf2), a central transcription factor in oxidative stress response related to numerous diseases, is activated after dissociating from the cytoskeleton−anchored Kelch−like ECH−associated protein 1 (Keap1). The Keap1–Nrf2 protein–protein interaction has become an important drug target. This study was designed to clarify whether antioxidantive phytochemicals inhibit the Keap1–Nrf2 protein–protein interaction and activate the Nrf2-ARE signaling pathway efficiently. Molecular docking and 3D−QSAR were applied to evaluate the interaction effects between 178 antioxidant phytochemicals and the Nrf2 binding site in Keap1. The Nrf2 activation effect was tested on a H 2 O 2 −induced oxidative−injured cell model. Results showed that the 178 phytochemicals could be divided into high−, medium−, and low−total−score groups depending on their binding affinity with Keap1, and the high−total−score group consisted of 24 compounds with abundant oxygen or glycosides. Meanwhile, these compounds could bind with key amino acids in the structure of the Keap1−Nrf2 interface. Compounds from high−total−score group show effective activation effects on Nrf2. In conclusion, phytochemicals showed high binding affinity with Keap1 are promising new Nrf2 activators. • 178 phytochemicals were collected and the Keap1-binding-affinity was estimated. • 24 compounds with high Keap1-binding-affinity was obtained. • Compounds with high Keap1-binding-affinity effectively activated Nrf2. [ABSTRACT FROM AUTHOR]

Edible flowers contain numerous phytochemicals which contribute to their health benefits, and consumption of edible flowers has increased significantly in recent years. While many researchers have been conducted, no literature review of the health benefits of common edible flowers and their phytochemicals has been compiled. This review aimed to present the findings of research conducted from 2000 to 2015 on the species, traditional application, phytochemicals, health benefits, and the toxicology of common edible flowers. It was found in 15 species of common edible flowers that four flavonols, three flavones, four flavanols, three anthocyanins, three phenolic acids and their derivatives were common phytochemicals and they contributed to the health benefits such as anti-oxidant, anti-inflammatory, anti-cancer, anti-obesity, and neuroprotective effect. Toxicology studies have been conducted to evaluate the safety of common edible flowers and provide information on their dosages and usages. [ABSTRACT FROM PUBLISHER]

Structure–activity relationships between 20 sterols and their thermal stabilities were studied in a model oil system. All sterol degradations were found to be consistent with a first-order kinetic model with determination of coefficient ( R 2 ) higher than 0.9444. The number of double bonds in the sterol structure was negatively correlated with the thermal stability of sterol, whereas the length of the branch chain was positively correlated with the thermal stability of sterol. A quantitative structure–activity relationship (QSAR) model to predict thermal stability of sterol was developed by using partial least squares regression (PLSR) combined with genetic algorithm (GA). A regression model was built with R 2 of 0.806. Almost all sterol degradation constants can be predicted accurately with R 2 of cross-validation equals to 0.680. Four important variables were selected in optimal QSAR model and the selected variables were observed to be related with information indices, RDF descriptors, and 3D-MoRSE descriptors. [ABSTRACT FROM AUTHOR]

BACKGROUND Phenolic compounds could be sensitive to digestive conditions, thus a simulated in vitro digestion-dialysis process and cellular assays was used to determine phenolic compounds and antioxidant and antiproliferative potentials of 10 common edible flowers from China and their functional components. RESULTS Gallic acid, ferulic acid, and rutin were widely present in these flowers, which demonstrated various antioxidant capacities ( DPPH, ABTS, FRAP and CAA values) and antiproliferative potentials measured by the MTT method. Rosa rugosa, Paeonia suffruticosa and Osmanthus fragrans exhibited the best antioxidant and antiproliferative potentials against HepG2, A549 and SGC-7901 cell lines, except that Osmanthus fragrans was not the best against SGC-7901 cells. The in vitro digestion-dialysis process decreased the antioxidant potential by 33.95-90.72% and the antiproliferative potential by 13.22-87.15%. Following the in vitro digestion-dialysis process, phenolics were probably responsible for antioxidant ( R2 = 0.794-0.924, P < 0.01) and antiproliferative ( R2 = 0.408-0.623, P < 0.05) potential. Moreover, gallic acid may be responsible for the antioxidant potential of seven flowers rich in edible flowers. CONCLUSION The antioxidant and antiproliferative potential of 10 edible flowers revealed a clear decrease after digestion and dialysis along with the reduction of phenolics. Nevertheless, they still had considerable antioxidant and antiproliferative potential, which merited further investigation in in vivo studies. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This study was aimed to classify the varieties and predict the antioxidant activity of Osmanthus fragrans flowers by UPLC–PDA/QTOF–MS and multivariable analysis. The PLS–DA model successfully classified the four varieties based on both the 21 identified compounds and the effective compounds. For the antioxidant activity prediction, PLS performed well to predict the antioxidant activity of O. fragrans flowers. Furthermore, acteoside, suspensaside A, ligustroside, forsythoside A, phillygenin and caffeic acid were selected as effective compounds by UVE–SPA for prediction. On the basis of effective compounds, PLS, MLR and PCR were applied to establish the calibration models. The UVE–SPA–MLR model was the optimal method to predict the antioxidant activity values with R p of 0.9200, 0.9010 and 0.8905 for DPPH, ABTS and FRAP assays, respectively. The results revealed that the UPLC–PDA/QTOF–MS combined with chemometrics could be a new method to classify the varieties and predict the antioxidant activity of O. fragrans flowers. [ABSTRACT FROM AUTHOR]

• The MMIPs NPs was synthesized combining bifunctional monomers strategy with magnetic nanotechnology. • Use of MAA and SSS improved the adsorption capacity and selectivity of the MMIPs NPs. • The MMIPs NPs were applied to extract 6-BA with satisfactory recoveries from vegetables. An adsorbent-magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) were synthesized for the extraction of 6-benzylaminopurine (6-BA) using Fe 3 O 4 as magnetic core. The MIPs were prepared with methacrylic acid and sodium p-styrene sulfonate as bifunctional monomers. The adsorbents were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometer, thermogravimetric analysis and vibrating sample magnetometer. The adsorption properties were evaluated by static, kinetic and selective adsorption experiments. The MMIPs NPs exhibit a high adsorption capacity (37.63 mg g−1) and favorable imprinting factor (2.88) toward 6-BA. The chromatogram of 6-BA extraction using the MMIPs NPs as the adsorbent demonstrates that the matrix interference has been minimized. More importantly, MMIPs NPs can be applied to extracting 6-BA from mung bean sprout and cucumber with satisfactory recoveries (91.14–104.52%), and can be reused for at least five times. This work provides a new strategy to efficiently extract 6-BA from vegetables. [ABSTRACT FROM AUTHOR]