Search

[Objective] Achieving a rapid, sensitive, and visual detection of 6-benzylaminopurine （6-BA） residues in vegetables. [Methods] Based on the peroxidase-like activity and specific recognition of Fe3O4 magnetic molecularly imprinted nanoparticles （Fe3O4 MMIP NPs）, a simple, rapid and highly selective colorimetric method was established to detect 6-BA residues in vegetables. [Results] Fe3O4 MMIP NPs exhibits optimal peroxidase-like catalytic activity at pH 4.0, 0.02 mol/L TMB, 0.02 mol/L H2O2 and a reaction time of 5 min. 6-BA showed a good linear relationship with the difference between the blank and the sample absorbance value in the mass concentration range of 1~300 ng/mL with a limit of detection at 0.697 ng/mL. The method was successfully applied to the detection of 6-BA residues in vegetables （cucumber, tomato, bean sprouts, mung bean sprouts）. The recovery rate was 83.47%~106.76%, with a relative standard deviation of 0.37%~5.66%. In addition, Fe3O4 MMIP NPs could still maintain good catalytic activity after 60 days of storage at 4 ℃. [Conclusion] The colorimetric method for the detection of 6-BA based on Fe3O4 MMIP NPs has the advantages of simplicity, rapidity, economy, and can be used for the detection of 6-BA residues in vegetables, which has certain reliability and practicability.

A colorimetric method for the determination of the peroxide value (POV) of edible vegetable oils was established based on the peroxidase-like catalytic activity of Fe3O4@COOH nanoenzyme. For five edible vegetable oils (corn oil, peanut oil, sunflower oil, rapeseed oil, and soybean oil), POV over the range of 0–0.3 g/100 g exhibited a good linear relationship with absorbance values. The proposed method could accurately detect the POV of edible vegetable oils oxidized in three different ways (ultraviolet lamp irradiation, oven heating and natural oxidation). The differences between the POV determined by this method and the national standard method for 25 oil samples were less than 0.05, and the relative standard deviations (RSDs) for corn oil, peanut oil, sunflower oil, rapeseed oil, and soybean oil were 6.13 %, 5.84 %, 6.82 %, 3.62 % and 5.75 %, respectively, indicating good practicability of the colorimetric method. This study provides a fast and convenient method for determining the POV of edible pure vegetable oils.

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]

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]

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]

In the present study, citrus peels were extracted using various conventional and deep eutectic solvents (DESs). Compared to other citrus peel extracts, the DES extract based on choline chloride showed notably higher total phenolic and flavonoid content levels, along with superior antioxidant activity, among these extracts. Consequently, this study aimed to further investigate the inhibitory effects of the choline chloride based DES extract on the production of both free and bound heterocyclic amines (HAs) and advanced glycation end products (AGEs) in roast pork meat patties. The results indicated that the addition of choline chloride-based DES extracts, particularly the choline chloride-carbamide based DES extract, can effectively reduce the oxidation of lipids and proteins by quenching free radicals. This approach proves to be the most efficient in reducing the formation of both HAs and AGEs, leading to a significant reduction of 19.1–68.3% and 11.5–66.5% in free and protein-bound HAs, respectively. Moreover, the levels of free and protein-bound AGEs were reduced by 50.8–50.8% and 30.5–39.8%, respectively, compared to the control group. Furthermore, the major phenolics of citrus peel extract identified by UHPLC-MS were polymethoxylated flavonoids (PMFs) including hesperidin, isosinensetin, sinensetin, tetramethoxyflavone, tangeretin, and hexamethoxyflavone, which inferring that these compounds may be the main active ingredients responsible for the antioxidant activity and inhibition effects on the formation of HAs and AGEs. Further research is needed to explore the inhibitory effects and mechanisms of PMFs with different chemical structures on the formation of HAs and AGEs. [ABSTRACT FROM AUTHOR]

Western dietary patterns (WDP) and typical food groups may play a major role in the risk of behavioral health disorders. Nevertheless, the relationships between WDP, common food categories, and mental health disorders lack consistency and remain incompletely understood in relation to potential mechanisms. Therefore, the objective of the present study was conducted to synthesize available evidence linking WDP and typical food groups to these outcomes. Web of Science, PubMed, EMBASE, and MEDLINE were searched up to August 2023. Random effect meta-analyses were performed to obtain pooled odds ratio and the relative risk for the prevalence of outcomes and the incidence of outcomes, respectively. A total of 54 articles were included. WDP was associated with increased risk of both depression (1.19; 95% CI: 1.06–1.32) and depressive symptoms (1.20; 95% CI: 1.08–1.34). Except for high-fat dairy products, food groups are associated with an increased risk of anxiety, depression, and depressive symptoms. This review presents evidence to further understand the relationship between WDP, typical food groups, and the incidence of behavioral health disorders, and more randomized controlled trials and cohort studies are urgently required to confirm these findings and elucidate potential mechanisms. [ABSTRACT FROM AUTHOR]

Long-term use of norfloxacin (NOR) will cause NOR residues in foods and harm human bodies. The determination of NOR residues is important for guaranteeing food safety. In this study, a simple, selective, and label-free colorimetric chemosensor for in situ NOR detection was developed based on Fe3O4 magnetic molecularly imprinted nanoparticles (Fe3O4 MMIP NPs). The Fe3O4 MMIP NPs showed good peroxidase-like catalytic activity to 3,3′,5,5′-tetramethylbenzidine (TMB) and selective adsorption ability to NOR. The colorimetric chemosensor was constructed based on the Fe3O4 MMIP NPs-H2O2-TMB reaction system. The absorbance differences were proportional to the concentrations of NOR in the range of 10–300 ng/mL with a limit of detection at 9 ng/mL. The colorimetric chemosensor was successfully applied to detect NOR residue in milk. The recovery range was 78.2–95.81%, with a relative standard deviation of 2.1–9.88%. Together, the proposed colorimetric chemosensor provides a reliable strategy for the detection of NOR residues in foods. [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]

Western dietary patterns (WDP) and typical food groups may play a major role in the risk of behavioral health disorders. Nevertheless, the relationships between WDP, common food categories, and mental health disorders lack consistency and remain incompletely understood in relation to potential mechanisms. Therefore, the objective of the present study was conducted to synthesize available evidence linking WDP and typical food groups to these outcomes. Web of Science, PubMed, EMBASE, and MEDLINE were searched up to August 2023. Random effect meta-analyses were performed to obtain pooled odds ratio and the relative risk for the prevalence of outcomes and the incidence of outcomes, respectively. A total of 54 articles were included. WDP was associated with increased risk of both depression (1.19; 95% CI: 1.06-1.32) and depressive symptoms (1.20; 95% CI: 1.08-1.34). Except for high-fat dairy products, food groups are associated with an increased risk of anxiety, depression, and depressive symptoms. This review presents evidence to further understand the relationship between WDP, typical food groups, and the incidence of behavioral health disorders, and more randomized controlled trials and cohort studies are urgently required to confirm these findings and elucidate potential mechanisms.

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., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Variations of phenylethanoid glycoside profiles and antioxidant activities in Osmanthus fragrans flowers through the digestive tract were evaluated by a simulated digestion model and UPLC/PDA/MS. Major phenylethanoid glycosides and phenolic acids, namely, salidroside, acteoside, isoacteoside, chlorogenic acid, and caffeic acid, were identified in four cultivars of O. fragrans flowers, and the concentration of acteoside was the highest, being up to 71.79 mg/g dry weight. After simulated digestion, total phenylethanoid glycoside contents and antioxidant activities were significantly decreased. Acteoside was identified as decomposing into caffeic acid, whereas salidroside was found to be stable during simulated digestion. According to Pearson's correlation analysis, acteoside contents showed good correlations with antioxidant activities during simulated digestion (R(2) = 0.994, P < 0.01). In conclusion, acteoside was the major contributor to the antioxidant activity of O. fragrans flowers, and salidroside was considered as the major antioxidant compound of O. fragrans flowers in vivo.