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1.
Food Chem ; 370: 130980, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34628238

RESUMO

Low bioavailability currently limits the potential of curcumin as a health-promoting dietary compound. This study therefore explored the potential of excipient emulsions to improve curcumin bioavailability. Oil-in-water excipient emulsions were prepared using different types of oils: corn oil, olive oil, and medium chain triglycerides (MCT). The excipient emulsions increased the transportation rate of curcumin across the Caco-2 cell monolayer and showed ability to protect curcumin from metabolism in the enterocytes, with the olive oil-based systems exhibiting the highest efficacy. In addition, most of curcumin metabolites were present as hexahydro-curcumin (HHC) and its conjugates. Our results show that excipient emulsions can improve curcumin bioavailability by increasing its trans-enterocyte absorption and reducing cellular metabolism. Moreover, they show that these effects depend on the type of oil used to produce them. These findings have important implications for the rational design of lipid-based delivery systems to enhance the bioavailability of hydrophobic nutraceuticals like curcumin.


Assuntos
Curcumina , Excipientes , Disponibilidade Biológica , Células CACO-2 , Óleo de Milho , Curcumina/metabolismo , Emulsões/metabolismo , Excipientes/metabolismo , Trato Gastrointestinal/metabolismo , Humanos
2.
Food Chem ; 370: 131303, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662794

RESUMO

Pleurotus eryngii is a valuable new edible mushroom variety cultivated on a large scale in China. The polysaccharides found in this mushroom are strong bioactive. This study used simulated digestion and fermentation model to study the digestion and fermentation characteristics of Pleurotus eryngii polysaccharide (PEP) and its effect on gut microbiota. The results showed that the molecular weight of PEP remained unchanged after simulated digestion, and the overall structure of PEP was not destroyed, indicating that PEP was not decomposed during digestion. However, during fermentation, PEP was degraded and utilized by intestinal flora to produce a variety of short-chain fatty acids (SCFAs), which reduced the pH value in fecal cultures. Meanwhile, PEP regulated the composition of intestinal flora, and the relative abundance of Firmicutes increased significantly. These suggests that PEP can be used as a functional food to promote intestinal health and prevent disease.


Assuntos
Pleurotus , Digestão , Fermentação , Polissacarídeos
3.
Food Chem ; 369: 130968, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34479013

RESUMO

Lipids usually contain a large ratio of polyunsaturated fatty acids (PUFAs), which are highly susceptible to oxidation. Presence of oxidized lipids in foods may affect the bioavailability of lipophilic bioactive components after ingestion. In this study, the effect of oxidized and unoxidized linoleic acid (LA) on the transport of a highly lipophilic bioactive citrus flavonoid (5-hydroxy - 6, 7, 8, 4' tetramethoxylflavone or 5-DMT) was determined using a Caco-2 cell model. Results demonstrated that compared to free 5-DMT, unoxidized LA improved the trans-enterocyte absorption of 5-DMT by stimulating the production of lipid droplets and chylomicrons. Although the amount of 5-DMT transported across the enterocyte doubled by oxidized LA compared to free 5-DMT, it significantly induced reactive oxygen species (ROS), affected the function of tight junction and caused damages to the morphology of enterocyte monolayer. This study re-emphasized the importance of preventing lipid oxidation in foods.


Assuntos
Citrus , Ácido Linoleico , Células CACO-2 , Quilomícrons , Enterócitos , Flavonoides , Humanos
4.
Food Chem ; 372: 131266, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34628117

RESUMO

The food-derived peptides hydrolyzed from native food protein matrix exhibited various bioactivities and multimeric structures, which make them the promising well-defined nanoplatforms candidates to co-deliver themselves with other bioactive compounds. In this study, zein-egg white derived peptides-chitosan (Z-EWDP-CS) ternary nanoparticles (NPs) were successfully fabricated by the spontaneous assembly to enhance the stability and bioactivity of curcumin (Cur). The novel ternary NPs exhibited a typical nano-spherical structure (138.63 nm, 40.50 mV), and adorable encapsulation efficiency (EE, 93.87%) for Cur. FTIR, XRD and DSC results verified that Cur changed from a crystalline state to an amorphous state, and was successfully entrapped in the cavity of Z-EWDP-CS NPs. Furthermore, the thermal stability, photochemical stability, salt stability, and antioxidant activity were considerably improved in the NPs after the addition of EWDP. Our results demonstrate that the food-derived peptides could be an ideal affinity agent for the co-delivery of themselves with hydrophobic nutraceuticals.


Assuntos
Quitosana , Curcumina , Nanopartículas , Zeína , Clara de Ovo , Tamanho da Partícula , Peptídeos
5.
Food Chem ; 372: 131213, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34638060

RESUMO

The metabolic fate of dietary compounds is closely related to their biological functions. Pterostilbene (PT) is a methylated stilbene found in many plant foods. Herein, we investigated gastrointestinal biotransformation and tissue distribution of PT in mice fed with 0.05% PT (w/w) for 5 weeks. PT and its major metabolites i.e. PT sulfate (PT-S), pinostilbene, pinostilbene sulfate, hydroxylated PT and hydroxylated PT sulfate were identified and quantified in the mucosa and content of the digestive tissues, blood, urine and vital organs. The results showed PT underwent demethylation, hydroxylation and conjugation in the small intestine, while the conjugated metabolites were largely deconjugated in the colon. Anaerobic fermentation with mouse cecal bacteria demonstrated the microbiota mediated deconjugation and demethylation of PT-S and PT, respectively. In conclusion, oral consumption of PT led to extensive biotransformation in mouse gastrointestinal tract and the metabolites of PT might play important roles in the bioactivity of PT.


Assuntos
Estilbenos , Animais , Biotransformação , Colo/metabolismo , Camundongos , Estilbenos/metabolismo , Distribuição Tecidual
6.
Carbohydr Polym ; 276: 118761, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34823784

RESUMO

BSH-1 is an O-acetylated xylan obtained from bamboo shavings. This study determined the protective effects of BSH-1 against loperamide (Lop)-induced constipation in mice. Mice received BSH-1 by gavage daily for 14 days. In constipated mice, BSH-1 significantly shortened the defecation time and raised the gastrointestinal (GI) transit rate, stool production, and cecal concentration of short-chain fatty acids (SCFAs). BSH-1 regulated the serum levels of gut hormones and neurotransmitters. BSH-1 also significantly altered the cecal microbiota of the constipated mice by increasing the abundance of potentially beneficial bacteria (e.g., Lactobacillus, Roseburia, and Bacteroidales_S24-7) and decreasing potentially pathogenic bacteria (e.g., Alloprevotella and Staphylococcus). Furthermore, colonic transcriptome analysis revealed that BSH-1 significantly reversed the expression changes of genes related to intestinal motility, water and ion transport, inflammation and cancer in constipated mice. Our findings indicated that BSH-1 effectively relieved Lop-induced constipation in mice and could be potentially used for constipation treatment.

7.
Biomater Sci ; 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34782897

RESUMO

Furin is an important cellular endoprotease, which is expressed at high levels in various cancer cells. Accurate and real-time detection of endogenous furin with high sensitivity and selectivity is significant for the diagnosis of cancer. Herein an activatable nanoprobe (MoS2@PDA-PEG/peptide, MPPF) with dual-mode near-infrared fluorescence (NIRF)/ratiometric photoacoustic (PA) imaging of endogenous furin activity has been developed. The MPPF nanoprobes were constructed by the covalent functionalization of polydopamine (PDA) coated MoS2 nanosheets (NSs) with Cy7-labeled furin substrate peptides. Upon cleavage of the peptides by furin, Cy7 molecules are released from MPPF nanoprobes and recover their fluorescence, realizing furin activity detection with the limit of detection (LOD) down to 3.73 × 10-4 U mL-1. Meanwhile, the ratio of the PA signal at 768 nm to that at 900 nm (PA768/PA900) decreases over time due to the destruction of fluorescence resonance energy transfer effect from Cy7 to MoS2 NSs and the rapid clearance of small Cy7 molecules from tissues. Thus, the simultaneous change in NIRF and ratiometric PA signals enables the imaging of endogenous furin activity in real time, and with high sensitivity, and high selectivity in both tumor cells and tumor-bearing mice.

8.
J Chem Phys ; 155(17): 174105, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34742189

RESUMO

In solid-state nuclear magnetic resonance, frequency-selective homonuclear dipolar recoupling is key to quantitative distance measurement or selective enhancement of correlations between atoms of interest in multiple-spin systems, which are not amenable to band-selective or broadband recoupling. Previous frequency-selective recoupling is mostly based on the so-called rotational resonance (R2) condition that restricts the application to spin pairs with resonance frequencies differing in integral multiples of the magic-angle spinning (MAS) frequency. Recently, we have proposed a series of frequency-selective homonuclear recoupling sequences called SPR (short for Selective Phase-optimized Recoupling), which have been successfully applied for selective 1H-1H or 13C-13C recoupling under from moderate (∼10 kHz) to ultra-fast (150 kHz) MAS frequencies. In this study, we fully analyze the average Hamiltonian theory of SPR sequences and reveal the origin of frequency selectivity in recoupling. The theoretical description, as well as numerical simulations and experiments, demonstrates that the frequency selectivity can be easily controlled by the flip angle (p) in the (p)ϕk(p)ϕk+π unit in the pSPR-Nn sequences. Small flip angles lead to frequency-selective recoupling, while large flip angles may lead to broadband recoupling in principle. The result shall shed new light on the design of homonuclear recoupling sequences with arbitrary frequency bandwidths.

9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(6): 1006-1010, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34841769

RESUMO

Objective: To observe the possible changes in the integrity of the cornea and corneal endothelial cells of children/adolescents with low or moderate myopia after long-term wearing of orthokeratology (ortho-k) lenses, as well as the time when the relevant changes occur, so as to evaluate the safety of long-term wearing of ortho-k lens and to provide a reference for the safety evaluation of subjects wearing ortho-k lenses. Methods: Subjects were recruited in the Contact Lens Clinic, West China Hospital, Sichuan University for a three-year prospective study. Ortho-k of the same brand was matched for the subjects. The central corneal thickness (CCT), corneal endothelial cell density (ECD), and hexagonal cell ratio (HEX) were measured prior to the wearing of ortho-k lenses and after wearing ortho-k lenses for 1 month, 3 months, 6 months, and every 3 months until 36 months. The results of corneal fluorescence staining were recorded during each follow-up. When corneal staining was observed, the Efron grading standard was used for grading and corresponding treatment was given. Results: A total of 33 (66 eyes) myopic patients were included in the study. 15 cases (46.2%) reported having binocular foreign body sensations and tearing within the first week of wearing the lenses. After the subjects became adapted to wearing the lenses, the symptoms disappeared without intervention. During the follow-up period, 31 cases (93.94%) of binocular corneal staining were observed, of which, 24 cases (72.73%) were graded as G0, receiving no treatment, 5 cases (15.15%) were graded as GⅠ, and 2 cases (6.06%) were graded as GⅡ. Corresponding clinical treatment for corneal staining was given to the GⅠ and GⅡ subjects. This study found that the corneal ECD was inversely proportional to age ( r=-0.380, P=0.002). During the three-year follow-up period, the subjects' left eye ECD decreased from the baseline at 24 months and the right eye ECD decreased from the baseline at 27 months ( P<0.05). The CCT results in the subjects showed that CCT became thinner at 1 month after wearing the lens ( P<0.05), but the follow-up CCT showed a stable trend. Conclusion: After three years of long-term follow-up, no serious corneal complications occurred in children/adolescents with moderate and low myopia after long-term wearing of ortho-k lens. The corneal ECD of both eyes started decreasing 24 months after wearing the ortho-k lenses and the CCT decreased 1 month after wearing the lenses.


Assuntos
Lentes de Contato , Miopia , Adolescente , Criança , Lentes de Contato/efeitos adversos , Córnea , Células Endoteliais , Humanos , Miopia/terapia , Estudos Prospectivos
10.
J Hazard Mater ; 424(Pt C): 127583, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34736213

RESUMO

Catalytic oxidation is a promising approach to eliminating formaldehyde (HCHO) to improve indoor air quality. Herein, CeO2 was explored due to its remarkable properties for oxygen storage and oxygen transfer capability for co-doping δ-MnO2 alongside cobalt for enhanced low-temperature oxidation of HCHO. Various characterization techniques were deployed to understand the morphology and physicochemical properties of the synthesized catalysts. The Co-Ce co-doped catalysts with low CeO2 loading (0.05 and 0.1) showed higher catalytic activity for HCHO oxidation due to their higher concentration of surface-active oxygen species. Catalytic oxidation results showed that the presence of CeO2 leads to the generation of methanol as a secondary hazardous pollutant. Methanol selectivity increases with increasing CeO2 loading in the catalysts. The results from in-situ DRIFTS confirmed the formation of methoxy species in the presence of CeO2, which are intermediates for methanol generation. Considering the recent interest in CeO2 as a potential catalyst for practical abatement of HCHO from the indoor environment, this work has thus raised questions on the safety of using CeO2 as a catalytic material for HCHO oxidation. It also provides insights into the surface reaction mechanism leading to the generation of methanol in the presence of CeO2.

11.
BMC Anesthesiol ; 21(1): 294, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34814841

RESUMO

BACKGROUND: In this study, we aimed to analyse survey data to explore two different hypotheses; and for this purpose, we distributed an online survey to Chinese anaesthesiologists. The hypothetical questions in this survey include: (1) Chinese anaesthesiologists mainly use the depth of anaesthesia (DoA) monitors to prevent intraoperative awareness and (2) the accuracy of these monitors is the most crucial performance factor during the clinical daily practice of Chinese anaesthesiologists. METHODS: We collected and statistically analysed the response of a total of 12,750 anesthesiologists who were invited to participate in an anonymous online survey. The Chinese Society of Anaesthesiologists (CSA) trial group provided the email address of each anaesthesiologist, and the selection of respondents was random from the computerized system. RESULTS: The overall response rate was 32.0% (4037 respondents). Only 9.1% (95% confidence interval, 8.2-10.0%) of the respondents routinely used DoA monitors. Academic respondents (91.5, 90.3-92.7%) most frequently used DoA monitoring to prevent awareness, whereas nonacademic respondents (88.8, 87.4-90.2%) most frequently used DoA monitoring to guide the delivery of anaesthetic agents. In total, the number of respondents who did not use a DoA monitor and whose patients experienced awareness (61.7, 57.8-65.6%) was significantly greater than those who used one or several DoA monitors (51.5, 49.8-53.2%). Overall, the crucial performance factor during DoA monitoring was considered by 61.9% (60.4-63.4%) of the respondents to be accuracy. However, most respondents (95.7, 95.1-96.3%) demanded improvements in the accuracy of the monitors for DoA monitoring. In addition, broad application in patients of all ages (86.3, 85.2-87.4%), analgesia monitoring (80.4, 79.2-81.6%), and all types of anaesthetic agents (75.6, 74.3-76.9%) was reported. In total, 65.0% (63.6-66.5%) of the respondents believed that DoA monitors should be combined with EEG and vital sign monitoring, and 53.7% (52.1-55.2%) believed that advanced DoA monitors should include artificial intelligence. CONCLUSIONS: Academic anaesthesiologists primarily use DoA monitoring to prevent awareness, whereas nonacademic anaesthesiologists use DoA monitoring to guide the delivery of anaesthetics. Anaesthesiologists demand high-accuracy DoA monitors incorporating EEG signals, multiple vital signs, and antinociceptive indicators. DoA monitors with artificial intelligence may represent a new direction for future research on DoA monitoring.

12.
ACS Appl Mater Interfaces ; 13(47): 55928-55938, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34786942

RESUMO

The synergy of chemodynamic therapy (CDT) and photothermal therapy (PTT) can improve anticancer efficacy, while the limited diffusion distance and the short lifetime of •OH still greatly restrict the therapeutic efficacy of PTT-CDT. Herein, MoS2@PDA-Fe@PEG/TPP (MPFPT) nanosheets (NSs) with mitochondria-targeting ability were reported for enhanced PTT-CDT synergistic oncotherapy. MPFPT NSs were prepared by covalent modification of poly(ethylene glycol) (PEG) and triphenylphosphonium (TPP) on polydopamine (PDA)-Fe3+coated MoS2 NSs. Co-localization experiments showed that MPFPT NSs can efficiently target mitochondria via the direction of TPP. Moreover, MPFPT NSs have good photothermal performance in the second near-infrared (NIR-II) region and can greatly accelerate the Fenton reaction from H2O2 to generate more hydroxyl radicals (•OH). In vitro experimental results showed that MPFPT NSs have improved therapeutic efficacy to cancer cells than similar MoS2-based nanoagents without mitochondria-targeting units, which can be attributed to the short distance between mitochondria and MPFPT NSs and the efficient damage of mitochondria by in situ generated •OH. In the 4T1 tumor-bearing mice model, MPFPT NSs demonstrated significantly enhanced therapeutic efficacy by PTT-CDT, suggesting the superiority of the mitochondria-targeting strategy. This study reveals that mitochondria-targeting MPFPT NSs are promising nanoagents for oncotherapy.

13.
Food Chem ; : 131277, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34799132

RESUMO

This study demonstrated the combination of black pepper and a canola oil-based emulsion synergistically enhanced carotenoid bioavailability of raw vegetables in humans. In a randomized crossover design, healthy young adults consumed (1) vegetable salad (control), (2) salad with canola oil emulsion (COE), (3) salad with black pepper (BP), and (4) salad with canola oil emulsion and black pepper (COE + BP). COE + BP led to a higher AUC0-10h of total plasma carotenoids (p < 0.0005) than the control (6.1-fold), BP (2.1-fold), and COE (3.0-fold). COE + BP increased AUC0-10h of plasma lutein, α-carotene, ß-carotene, and lycopene by 4.8, 9.7, 7.6, and 5.5-fold than the control, respectively (p < 0.0001). COE + BP produced a significant synergy in increasing both Cmax and AUC0-10h of total carotenoids, α-carotene, ß-carotene, and lycopene. Moreover, COE + BP produced a stronger enhancement on AUC0-10h of total carotenoids, α-carotene, ß-carotene, and lycopene in females than in males.

14.
Crit Rev Food Sci Nutr ; : 1-19, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34839776

RESUMO

Consumers today are increasingly willing to reduce their meat consumption and adopt plant-based alternatives in their diet. As a main source of plant-based foods, cereals and legumes (CLs) together could make up for all the essential nutrients that humans consume daily. However, the consumption of CLs and their derivatives is facing many challenges, such as the poor palatability of coarse grains and vegetarian meat, the presence of anti-nutritional factors, and allergenic proteins in CLs, and the vulnerability of plant-based foods to microbial contamination. Recently, high hydrostatic pressure (HHP) technology has been used to tailor the techno-functionality of plant proteins and induce cold gelatinization of starch in CLs to improve the edible quality of plant-based products. The nutritional value (e.g., the bioavailability of vitamins and minerals, reduction of anti-nutritional factors of legume proteins) and bio-functional properties (e.g., production of bioactive peptides, increasing the content of γ-aminobutyric acid) of CLs were significantly improved as affected by HHP. Moreover, the food safety of plant-based products could be significantly improved as well. HHP lowered the risk of microbial contamination through the inactivation of numerous microorganisms, spores, and enzymes in CLs and alleviated the allergy symptoms from consumption of plant-based foods.

15.
Mov Disord ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34820915

RESUMO

BACKGROUND: Paroxysmal kinesigenic dyskinesia (PKD) is the most common type of paroxysmal dyskinesias. Only one-third of PKD patients are attributed to proline-rich transmembrane protein 2 (PRRT2) mutations. OBJECTIVE: We aimed to explore the potential causative gene for PKD. METHODS: A cohort of 196 PRRT2-negative PKD probands were enrolled for whole-exome sequencing (WES). Gene Ranking, Identification and Prediction Tool, a method of case-control analysis, was applied to identify the candidate genes. Another 325 PRRT2-negative PKD probands were subsequently screened with Sanger sequencing. RESULTS: Transmembrane Protein 151 (TMEM151A) variants were mainly clustered in PKD patients compared with the control groups. 24 heterozygous variants were detected in 25 of 521 probands (frequency = 4.80%), including 18 missense and 6 nonsense mutations. In 29 patients with TMEM151A variants, the ratio of male to female was 2.63:1 and the mean age of onset was 12.93 ± 3.15 years. Compared with PRRT2 mutation carriers, TMEM151A-related PKD were more common in sporadic PKD patients with pure phenotype. There was no significant difference in types of attack and treatment outcome between TMEM151A-positive and PRRT2-positive groups. CONCLUSIONS: We consolidated mutations in TMEM151A causing PKD with the aid of case-control analysis of a large-scale WES data, which broadens the genotypic spectrum of PKD. TMEM151A-related PKD were more common in sporadic cases and tended to present as pure phenotype with a late onset. Extensive functional studies are needed to enhance our understanding of the pathogenesis of TMEM151A-related PKD. © 2021 International Parkinson and Movement Disorder Society.

16.
Materials (Basel) ; 14(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34832404

RESUMO

In this research, a high-boron-content composite material with both neutron and γ rays shielding properties was developed by an optimized design and manufacture. It consists of 304 stainless steel as the matrix and spherical boron carbide (B4C) particles as the functional particles. The content of B4C is 24.68 wt%, and the particles' radius is 1.53 mm. The density of the newly designed material is 5.17 g·cm-3, about 68.02% of that of traditional borated stainless steel containing 1.7 wt% boron, while its neutrons shielding performance is much better. Firstly, focusing on shielding properties and material density, the content and the size of B4C were optimized by the Genetic Algorithm (GA) program combined with the MCNP program. Then, some samples of the material were manufactured by the infiltration casting technique according to the optimized results. The actual density of the samples was 5.21 g cm-3. In addition, the neutron and γ rays shielding performance of the samples and borated stainless steel containing 1.7 wt% boron was tested by using an 241Am-Be neutron source and 60Co and 137Cs γ rays sources, respectively, and the results were compared. It can be concluded that the new designed material could be used as a material for nuclear power plants or spent-fuel storage and transportation containers with high requirements for mobility.

17.
Crit Rev Food Sci Nutr ; : 1-24, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609268

RESUMO

Citrus fruits are consumed in large quantities worldwide due to their attractive aromas and taste, as well as their high nutritional values and various health-promoting effects, which are due to their abundance of nutrients and bioactives. In addition to water, carbohydrates, vitamins, minerals, and dietary fibers are important nutrients in citrus, providing them with high nutritional values. Citrus fruits are also rich in various bioactives such as flavonoids, essential oils, carotenoids, limonoids, and synephrines, which protect from various ailments, including cancer and inflammatory, digestive, and cardiovascular diseases. The composition and content of nutrients and bioactives differ significantly among citrus varieties, fruit parts, and growth stages. To better understand the nutrient and bioactive profiles of citrus fruits and provide guidance for the utilization of high-value citrus resources, this review systematically summarizes the nutrients and bioactives in citrus fruit, including their contents, structural characteristics, and potential health benefits. We also explore the composition variation in different citrus varieties, fruits parts, and growth stages, as well as their health-promoting effects and applications.

18.
Crit Rev Food Sci Nutr ; : 1-21, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34672231

RESUMO

Flavonoids have been attracting increasing research interest because of their multiple health promoting effects. However, many flavonoids with similar structures are present in foods, often at low concentrations, which increases the difficulty of their separation and identification. Liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-Q-TOF-MS/MS) has become one of the most widely used techniques for flavonoid detection. LC-Q-TOF-MS/MS can achieve highly efficient separation by LC; it also provides structural information regarding flavonoids by Q-TOF-MS/MS. This review presents a comprehensive summary of the scientific principles and detailed methodologies (e.g., qualitative determination, quantitative determination, and data processing) of LC-Q-TOF-MS/MS specifically for food flavonoids. It also discusses the recent applications of LC-Q-TOF-MS/MS in determination of flavonoid types and contents in agricultural products, changes in their structures and contents during food processing, and metabolism in vivo after consumption. Moreover, it proposes necessary technological improvements and potential applications. This review would facilitate the scientific understanding of theory and technique of LC-Q-TOF-MS/MS for flavonoid detection, and promote its applications in food and health industry.

19.
J Nanobiotechnology ; 19(1): 320, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645456

RESUMO

Since the number of raw material selections for the synthesis of carbon dots (CDs) has grown extensively, herbal medicine as a precursor receives an increasing amount of attention. Compared with other biomass precursors, CDs derived from herbal medicine (HM-CDs) have become the most recent incomer in the family of CDs. In recent ten years, a great many studies have revealed that HM-CDs tend to be good at theranostics without drug loading. However, the relevant development and research results are not systematically reviewed. Herein, the origin and history of HM-CDs are outlined, especially their functional performances in medical diagnosis and treatment. Besides, we sort out the herbal medicine precursors, and analyze the primary synthetic methods and the key characteristics. In terms of the applications of HM-CDs, medical therapeutics, ion and molecular detection, bioimaging, as well as pH sensing are summarized. Finally, we discuss the crucial challenges and future prospects.

20.
Sci Total Environ ; 807(Pt 2): 150306, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34634352

RESUMO

Aim at the effects of the coastal characteristic on ozone pollution in the Yangtze River Delta (YRD), a campaign was launched at the Ningbo, China in the summer of 2020, which mainly covered the monitoring of the vertical profiles of ozone (O3) concentration, three-dimensional wind field, temperature and humidity profiles and parameters of boundary layer dynamic-thermodynamic structure. At the coastal research station, a sea-land breeze (SLB) circulation accompanied by a concurrent coastal low-level jets (CLLJ) structure was observed and identified during 11-12 May 2020. The sea breeze first formed at 10:00 LT on 11 May, turned to land breeze at night, and returned to sea breeze again at 10:00 LT the next morning, prevailing at altitudes of 0-0.5 km and 0-0.3 km respectively. Land breeze at night carries O3 from the inland to the sea forming high ozone levels over the sea, and the shift of the sea breeze during daytime further blew pollution back to the land. Additionally, the conversion of SLB contributed to the occurrence of CLLJ at the altitudes of ~0.3-0.7 km by 02:00 and 06:00 LT, of which the center of wind speed reached ~13 m s-1. The CLLJ-induced turbulent activity decoupled the residual layer (RL) and stable boundary layer, leading to a reduction of RL-O3 levels and an increase of ~50 µg m-3 in surface-O3 concentration. The YRD's unique coastal characteristics make O3 pollution causes in coastal areas more complicated.

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