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1.
Skin Res Technol ; 29(3): e13218, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36973986

RESUMEN

BACKGROUND: Skin measurements of transepidermal water loss (TEWL) and stratum corneum hydration (SCH) reflect different aspects of skin physiology. Since epidermal water loss depends on epidermal-to-air water vapor gradients, a possible quantitative relationship between TEWL and SCH may exist. This investigation's purpose was to test the possible TEWL-SCH relationship. MATERIALS AND METHODS: SCH and TEWL were measured noninvasively on forearm and palmer thenar eminence (hand) in 40 young adults (20 males) along with total body fat percentage (FAT) via bioimpedance. RESULTS: A significant positive nonlinear correlation (p < 0.001) was detected between SCH and TEWL in hands of the male cohort that occurred when SCH exceeded a threshold level. This threshold level was not exceeded in male or female forearms and forearms did not display a SCH-TEWL correlation. There was a weak inverse dependence of TEWL on FAT on both forearm and hand (p < 0.05), but no SCH-FAT relationship was observed. TEWL values on the forearm and hand were moderately correlated with each other (p = 0.002) but SCH values were not. CONCLUSION: The findings clarify the relationship between forearm and palmer hydration and TEWL values, and their relationship to total body fat percentages in young healthy adults. The significant correlation between palmer stratum corneum hydration and palmer TEWL that was discovered in the male but not the female cohort suggests a threshold hydration level for which TEWL depends both on skin barrier function and stratum corneum hydration. This implies that conditions with increased SCH may in part account for elevated TEWL values.


Asunto(s)
Epidermis , Antebrazo , Mano , Pérdida Insensible de Agua , Femenino , Humanos , Masculino , Adulto Joven , Epidermis/química , Epidermis/metabolismo , Epidermis/fisiología , Antebrazo/fisiología , Mano/fisiología , Piel/química , Piel/metabolismo , Fenómenos Fisiológicos de la Piel , Pérdida Insensible de Agua/fisiología , Vapor/análisis , Estado de Hidratación del Organismo
2.
Food Chem ; 402: 134237, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36174350

RESUMEN

This study developed two novel food packaging films, oat protein/pullulan (Op/Pul) and Nisin-loaded oat protein/pullulan (Nis@Op/Pul) films. Ultrasound was introduced to improve its mechanical, structural and physicochemical properties. The Op/Pul film has lower light transmittance, water vapour and oxygen permeability (OP) and improved film uniformity than pure oat protein and pullulan film. The addition of Nisin led to a significant decrease in the composite films' transparency, moisture content, and total soluble matter (TSM). The ultrasound treatment significantly increased the elongation at break and transparency of Nis@Op/Pul film by 18.37% and 8.03% and decreased its TSM and OP by 8.33% and 2.78%, respectively, compared to the conventional method. The structure analysis shows ultrasound enhances intermolecular hydrogen bonding, reduces the crystallinity and formed a more regular, uniform surface. Moreover, the Nis@Op/Pul film prepared by ultrasound treatment could effectively delay the decay and deterioration of fresh strawberries and prolong their shelf life.


Asunto(s)
Nisina , Nisina/química , Avena , Vapor/análisis , Ultrasonido , Embalaje de Alimentos , Permeabilidad , Oxígeno/análisis
3.
Food Chem ; 405(Pt A): 134821, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36370572

RESUMEN

For efficient and comprehensive detection of the staling degree of Chinese steamed bread (CSB), staled CSB samples stored for 0-16 days were prepared and analyzed using near-infrared (NIR), mid-infrared (MIR), and Raman spectroscopy combined with data fusion. Among three data fusion schemes, decision-level fusion achieved the best performance when quantifying the CSB staling degree according to the soluble starch amylose fraction, relative crystallinity, and hardness, with determination coefficients and root mean square errors for the validation set in the range of 0.928-0.986 and 0.015-1.290, respectively. The relative percent deviation values of the three indicators increased to 8.362, 4.735, and 3.617, respectively. These results indicate that the combination of NIR, MIR, and Raman spectroscopy as a decision-level fusion scheme can achieve efficient, comprehensive, and accurate quantification of the staling degree of CSB. This research has important applications for food quality, safety, and shelf-life evaluations.


Asunto(s)
Pan , Almidón , Pan/análisis , Almidón/química , Vapor/análisis , Amilosa , China
4.
Food Chem ; 401: 134162, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36096007

RESUMEN

This study aimed to develop a low-density polyethylene-based multilayer active packaging film with three layers. The core layer was an active layer containing pumice and potassium permanganate, while the skin layer was the barrier layer impregnated with sodium chloride. The multilayer film showed an ethylene scavenging capacity of 1.6 µmol/(25 in2) within 8 d at 25 °C and was endowed with water absorption capacity. In addition, the oxygen and water vapor permeability of the multilayer film were improved in comparison to the neat one. Further, the multilayer film extended the shelf life of avocado from less than 10 d to 16 d at 25 °C, controlled ethylene and carbon dioxide concentrations, and caused a reduction in the loss of flesh firmness and weight. More importantly, according to migration testing, active agents in the core layer would not migrate to avocado peel, which ensured that avocados would not be contaminated.


Asunto(s)
Persea , Polietileno , Embalaje de Alimentos , Permanganato de Potasio , Vapor/análisis , Dióxido de Carbono , Cloruro de Sodio , Etilenos , Oxígeno
5.
Artículo en Inglés | MEDLINE | ID: mdl-36360679

RESUMEN

Cured-in-place pipe (CIPP) is one of the most popular in situ rehabilitation techniques to repair sewer and water pipes. While there are multiple approaches to curing CIPP, steam-curing of styrene-based resins has been found to be associated with air-borne chemical emissions. Health officials, utilities and industry representatives have recognized the need to know more about these emissions, especially styrene. Such concern has led to multiple studies investigating the concentrations of volatile organic compounds on CIPP installation sites. This study expands upon previous effort by modeling worst-case, steam-cured CIPP emissions over a 5-year weather record. The effort also includes calibration of the model to emissions averages over the work day rather than instantaneous field measurements. Dispersion modelling software, AERMOD, was utilized to model the styrene component of CIPP emissions on two CIPP installation sites in the US. Based on the analysis results, it was found that the styrene emitted from stacks dissipates rapidly with styrene concentrations only exceeding minimum health and safety threshold levels at distances close to the stack (2 m or less). The values predicted by the model analysis are comparable with the field measured styrene concentrations from other studies. Current safety guidelines in the US recommend a 4.6-m (15-ft) safety perimeter for stack emission points. The results of this study indicate that significant and lasting health impacts are unlikely outside recommended safety perimeter. The results also validate the importance of enforcing recommended safety guidance on steam-cured CIPP sites.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Compuestos Orgánicos Volátiles , Estireno/análisis , Monitoreo del Ambiente/métodos , Vapor/análisis , Contaminación del Aire/análisis , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis
6.
Molecules ; 27(19)2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36234820

RESUMEN

Steaming is a characteristic pharmaceutical skill in Traditional Chinese Medicine (TCM). Polygonum multiflorum radix (PM) and its steamed products have been used in Asia for centuries. Raw Polygonum multiflorum radix (RPM) is commonly used to promote defecation but can exert toxicity, especially in liver injury. However, RPM can be made converted into Polygoni multiflori radix praeparata (PMP) by steaming; this is considered a good method to reduce defecation and liver injury caused by PM in Asia. The chemical constituents of TCM are the key to its action. We systematically analyzed the effect of steaming on PM constituents, defecation, and liver injury. We identified 13 main constituents from PM and PMP; the results showed that after being steamed, two constituents (TSG, catechin) had decreased, six constituents (such as procyanidin B1 or B2) had disappeared, four constituents (such as emodin, physcion) had increased, emodin-8-O-ß-D-glucoside remained unchanged in PMP. Pharmacological experiments showed that PM could promote defecation; however, there were no obvious effects in response to PMP. Only a high dose of PM for 14 days caused some degree of liver injury, although this injury disappeared after 14 days of drug withdrawal. Network pharmacology and molecular docking studies showed that TSG, emodin and physcion were the most effective in promoting defecation and causing liver injury. Collectively, our findings show that steaming can reduce the effect of PM on promoting defecation and reducing liver injury. TSG may be one of the important constituents in PM that can promote defecation and cause liver injury.


Asunto(s)
Catequina , Medicamentos Herbarios Chinos , Emodina , Fallopia multiflora , Polygonum , Catequina/farmacología , Defecación , Medicamentos Herbarios Chinos/química , Emodina/análogos & derivados , Emodina/farmacología , Hígado , Simulación del Acoplamiento Molecular , Raíces de Plantas/química , Polygonum/química , Vapor/análisis
7.
Carbohydr Polym ; 298: 120064, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36241263

RESUMEN

Although polyvinyl alcohol (PVA) is a promising biodegradable packaging material, it presents some disadvantages for food packaging such as poor ultraviolet (UV) and water vapor barrier properties, low mechanical strength, poor water resistance, and lack of antimicrobial properties. To overcome these limitations, novel PVA/cellulose nanocrystals (CNC)/titanium dioxide (TiO2) nanocomposites were developed, characterized, and demonstrated for potential food packaging applications. The mechanical strength, water vapor barrier, and UV barrier properties of PVA/CNC/TiO2 5 % film (5 wt% TiO2 in the PVA/CNC matrix with 5 wt% of CNCs) increased by 55.8 %, 45.2 %, and 70,056.8 %, respectively, compared to those of a PVA film. In the antibacterial simulation test, PVA/CNC/TiO2 5 % film could limit the growth of microorganisms for 14 days. In packaging tests with fresh garlic, PVA/CNC/TiO2 films effectively prevented weight loss and spoilage by external influences, indicating the potential of the PVA/CNC/TiO2 nanocomposites for food-packaging applications.


Asunto(s)
Antiinfecciosos , Nanocompuestos , Nanopartículas , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Celulosa/química , Celulosa/farmacología , Embalaje de Alimentos , Nanocompuestos/química , Nanopartículas/química , Alcohol Polivinílico/química , Vapor/análisis , Titanio
8.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36142238

RESUMEN

Plants produce a variety of high-value chemicals (e.g., secondary metabolites) which have a plethora of biological activities, which may be utilised in many facets of industry (e.g., agrisciences, cosmetics, drugs, neutraceuticals, household products, etc.). Exposure to various different environments, as well as their treatment (e.g., exposure to chemicals), can influence the chemical makeup of these plants and, in turn, which chemicals will be prevalent within them. Essential oils (EOs) usually have complex compositions (>300 organic compounds, e.g., alkaloids, flavonoids, phenolic acids, saponins and terpenes) and are obtained from botanically defined plant raw materials by dry/steam distillation or a suitable mechanical process (without heating). In certain cases, an antioxidant may be added to the EO (EOs are produced by more than 17,500 species of plants, but only ca. 250 EOs are commercially available). The interesting bioactivity of the chemicals produced by plants renders them high in value, motivating investment in their production, extraction and analysis. Traditional methods for effectively extracting plant-derived biomolecules include cold pressing and hydro/steam distillation; newer methods include solvent/Soxhlet extractions and sustainable processes that reduce waste, decrease processing times and deliver competitive yields, examples of which include microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and supercritical CO2 extraction (scCO2). Once extracted, analytical techniques such as chromatography and mass spectrometry may be used to analyse the contents of the high-value extracts within a given feedstock. The bioactive components, which can be used in a variety of formulations and products (e.g., displaying anti-aging, antibacterial, anticancer, anti-depressive, antifungal, anti-inflammatory, antioxidant, antiparasitic, antiviral and anti-stress properties), are biorenewable high-value chemicals.


Asunto(s)
Aceites Volátiles , Saponinas , Antibacterianos/química , Antifúngicos/análisis , Antioxidantes/química , Antiparasitarios , Antivirales/análisis , Dióxido de Carbono/química , Flavonoides , Aceites Volátiles/química , Extractos Vegetales/química , Plantas , Solventes/química , Vapor/análisis , Terpenos
9.
Int J Mol Sci ; 23(18)2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36142543

RESUMEN

The azo dye orange II is used extensively in the textile sector for coloring fabrics. High concentrations of it are released into aqueous environments through textile effluents. Therefore, its removal from textile wastewater and effluents is necessary. Herein, initially, we tested 11 bacterial strains for their capabilities in the degradation of orange II dye. It was revealed in the preliminary data that B. subtilis can more potently degrade the selected dye, which was thus used in the subsequent experiments. To achieve maximum decolorization, the experimental conditions were optimized whereby maximum degradation was achieved at: a 25 ppm dye concentration, pH 7, a temperature of 35 °C, a 1000 mg/L concentration of glucose, a 1000 mg/L urea concentration, a 666.66 mg/L NaCl concentration, an incubation period of 3 days, and with hydroquinone as a redox mediator at a concentration of 66.66 mg/L. The effects of the interaction of the operational factors were further confirmed using response surface methodology, which revealed that at optimum conditions of pH 6.45, a dye concentration of 17.07 mg/L, and an incubation time of 9.96 h at 45.38 °C, the maximum degradation of orange II can be obtained at a desirability coefficient of 1, estimated using the central composite design (CCD). To understand the underlying principles of degradation of the metabolites in the aliquot mixture at the optimized condition, the study steps were extracted and analyzed using GC-MS(Gas Chromatography Mass Spectrometry), FTIR(Fourier Transform Infrared Spectroscopy), 1H and carbon 13 NMR(Nuclear Magnetic Resonance Spectroscopy). The GC-MS pattern revealed that the original dye was degraded into o-xylene and naphthalene. Naphthalene was even obtained in a pure state through silica gel column isolation and confirmed using 1H and 13C NMR spectroscopic analysis. Phytotoxicity tests on Vigna radiata were also conducted and the results confirmed that the dye metabolites were less toxic than the parent dye. These results emphasize that B. subtilis should be used as a potential strain for the bioremediation of textile effluents containing orange II and other toxic azo dyes.


Asunto(s)
Bacillus subtilis , Agua Carbonatada , Compuestos Azo/química , Compuestos Azo/toxicidad , Bacillus subtilis/metabolismo , Bencenosulfonatos , Biodegradación Ambiental , Carbono/análisis , Agua Carbonatada/análisis , Colorantes/química , Glucosa , Hidroquinonas , Naftalenos/análisis , Gel de Sílice , Cloruro de Sodio , Vapor/análisis , Textiles , Urea , Aguas Residuales/química , Agua/análisis
10.
Molecules ; 27(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36144531

RESUMEN

This research work investigates the development of alginate-based films incorporating phenolic compounds extracted from Amaranthus cruentus grain using different solvents. Alginate, glycerol, and amaranth grain phenolic compounds at various concentrations were used to produce the films. An experimental Central Composite Rotatable Design (CCRD) was used to evaluate the effect of these variables on different film's properties, i.e., water vapor permeability, hydrophobicity, moisture content, solubility, thermal, mechanical, and optical properties. This study demonstrated that high phenolic compound content and antioxidant capacity were obtained from amaranth grain using ethanol as the extraction solvent. Alginate films incorporating amaranth phenolic compounds were successfully manufactured, and this study can be used to tailor the formulation of alginate films containing amaranth phenolic compounds, depending on their final food application. For example, less flexible but more resistant and water-soluble films can be produced by increasing the alginate concentration, which was confirmed by a Principal Component Analysis (PCA) and Partial Least Squares (PLS) analysis. This study showed that active alginate films with amaranth phenolic compounds can be tailored to be used as food packaging material with potential antioxidant activity.


Asunto(s)
Amaranthus , Alginatos , Antioxidantes/análisis , Antioxidantes/farmacología , Grano Comestible/química , Etanol/análisis , Glicerol/análisis , Fenoles/análisis , Extractos Vegetales , Solventes/análisis , Vapor/análisis
11.
Sci Total Environ ; 853: 158597, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36089039

RESUMEN

Atmospheric humidity has been shown to promote haze formation, but it remains unclear why the air is humid during heavy haze days in winter. Here we combine water vapor isotope measurements with WRF-Chem simulations to elucidate increasing humidity with aggravation of haze during wintertime in urban Beijing. The vapor isotopic analysis in Beijing shows that the combustion-derived water (CDW) constitutes 11.0± 6.2 % of the atmospheric moisture and its fraction in total moisture increases with aggravation of haze. Modeling results reveal that, in addition to the water vapor transported from south or east to Beijing with occurrence of haze, CDW has a considerable impact on the increasing humidity when haze becomes heavy or severe. Aerosol-radiation interactions generally decrease the water vapor content and only increase humidity with occurrence of severe haze with hourly PM2.5 concentrations exceeding 250µg m-3. Although CDW is insignificant in the global atmospheric vapor budget, it could play an important role in modifying the local weather during haze days.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Beijing , Monitoreo del Ambiente , Vapor/análisis , Aerosoles/análisis , Estaciones del Año , Contaminación del Aire/análisis , China
12.
Environ Pollut ; 313: 120059, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36049576

RESUMEN

The process improvement, a pilot remediation test and the decontamination mechanism of microwave-induced steam distillation (MISD) for petroleum hydrocarbons (PHs) removal were conducted. Processes of multistage steam distillation and carbon reinforcement were compared to determine the best remediation process. Pilot project was then carried out to explore the applicability of MISD in site-scale remediation. The remediation efficiency, procedures and influencing factors of site-scale MISD project were studied by monitoring variations of soil moisture, temperature and PHs concentrations. Furthermore, the decontamination mechanisms of PHs were clarified based on kinetic analysis. The results showed that the multistage steam distillation could improve 10%∼15% remediation efficiency, and the carbon reinforcement could shorten remediation duration of each steam distillation stage by 50%. Pilot MISD project adopted multistage steam distillation process and went through four (initial, rapid heating-up, gentle heating-up and quasi-equilibrium) remediation stages (overall temperature ≤100 °C). The final PHs removal rate was about 60%, which would get better with greater proportion of low boiling points components and stronger vapor extraction. Kinetic studies showed that PHs was removed by steam stripping and limited by intraparticle diffusion in the "steam distillation zone", while local high temperature (>100 °C) greatly improved PHs volatilization and provided activation energy for PHs desorbed and degraded in the "selective heating zone".


Asunto(s)
Petróleo , Contaminantes del Suelo , Carbono , Destilación , Hidrocarburos , Cinética , Microondas , Petróleo/análisis , Proyectos Piloto , Suelo , Contaminantes del Suelo/análisis , Vapor/análisis
13.
Int J Biol Macromol ; 216: 927-939, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35917854

RESUMEN

In this study, nanocomposites of polylactic acid (PLA) with clove essential oil (CEO) and alkali treated halloysite nanotubes (NHNT) as fillers were synthesized by using simple solvent casting method. The treatment of halloysite nanotubes with NaOH increased the surface area from 50.16 m2⋅g-1 to 57.01 m2⋅g-1 and pore volume from 0.25 cm3⋅g-1 to 0.32 cm3⋅g-1. The as-synthesized nanocomposite films were characterized for physical, thermal, mechanical and water vapor barrier properties towards their use as food packaging material. The nanocomposite film PCOH0.5 (consisting 0.5 wt% NHNT and 200 µL CEO) possessed the best physical properties with percentage enhancements over PLA as: surface hydrophobicity (20.2 %), water vapor barrier (42.1 %), thermal stability (3.2 %), flexibility (682 %), tensile strength (20 %), elastic modulus (38 %), UV barrier property (62 %). In addition, a practical packaging test was performed on cut apples stored at room temperature for 6 days. The PCOH0.5 films showed substantially improved results (as compared to PLA) as follows: weight loss (40.5 %), mesophilic count (4.0 %), firmness (116.6 %), titratable acidity (110.8 %), pH (2.9 %) and total soluble solids (8.9 %). The results clearly indicate the efficiency of PLA/CEO/NHNT nanocomposite films as potential active food packaging material.


Asunto(s)
Nanocompuestos , Nanotubos , Aceites Volátiles , Syzygium , Álcalis , Arcilla , Aceite de Clavo/química , Embalaje de Alimentos/métodos , Nanocompuestos/química , Aceites Volátiles/química , Poliésteres/química , Vapor/análisis , Syzygium/química
14.
Chemosphere ; 308(Pt 1): 136182, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36037942

RESUMEN

Volatile organic compounds (VOCs) are a group of organic compounds that have a molecular structure containing carbon and their chemical properties allow them to be easily converted to steam and gas and remain for a long period of time and have diverse effects on the environment. The purpose of this study is determination of the concentration of VOCs such as alachlor, anthracene, benzene, bromoform, chloroform, heptachlor, isophorone, tetrachloroethylene, γ -chlordane, toluene, etc. in water matrices. The results showed that among studies conducted on VOCs, the concentration of tetrachloroethylene, m,p-xylene, and toluene were at the top in water matrices, and the lowest average concentrations were found in chloroform, anthracene, and butyl benzyl phthalate. In terms of VOC concentrations in water matrices, China was the most polluted country. Moreover, the data analysis indicated that China was the only country with carcinogenic risk. A Monte-Carlo simulation showed that although the averages obtained were comparable to the acceptable limits, for heptachlor, the maximum carcinogenic risk is achieved at a level that is slightly over the limit, only 25% from the population being exposed.


Asunto(s)
Contaminantes Atmosféricos , Tetracloroetileno , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Antracenos/análisis , Benceno/análisis , Carbono/análisis , China , Clordano/análisis , Cloroformo/análisis , Monitoreo del Ambiente/métodos , Heptacloro/análisis , Vapor/análisis , Tetracloroetileno/análisis , Tolueno/análisis , Compuestos Orgánicos Volátiles/análisis , Agua/análisis
15.
Environ Pollut ; 312: 120014, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36007793

RESUMEN

Polycyclic aromatic compounds (PACs) are organic compounds commonly found in contaminated soil. Previous studies have shown the removal of polycyclic aromatic hydrocarbons (PAHs) in creosote-contaminated soils during steam enhanced extraction (SEE). However, less is known about the removal of alkyl-PAHs and heterocyclic compounds, such as azaarenes, and oxygen- and sulfur-heterocyclic PACs (OPACs and PASHs, respectively). Further, the impact of SEE on the freely dissolved concentration of PACs in soil as well as the soil bioactivity pre- and post-SEE have yet to be addressed. To fulfil these research gaps, chemical and bioanalytical analysis of a creosote-contaminated soil, collected from a U.S. Superfund site, pre- and post-SEE were performed. The decrease of 64 PACs (5-100%) and increase in the concentrations of nine oxygenated-PAHs (OPAHs) (150%) during SEE, some of which are known to be toxic and can potentially contaminate ground water, were observed. The freely dissolved concentrations of PACs in soil were assessed using polyoxymethylene (POM) strips and the concentrations of 66 PACs decreased post-SEE (1-100%). Three in vitro reporter gene bioassays (DR-CALUX®, ERα-CALUX® and anti-AR CALUX®) were used to measure soil bioactivities pre- and post-SEE and all reporter gene bioassays measured soil bioactivity decreases post-SEE. Mass defect suspect screening tentatively identified 27 unique isomers of azaarenes and OPAC in the soil. As a remediation technique, SEE was found to remove alkyl-PAHs and heterocyclic PACs, reduce the concentrations of freely dissolved PACs, and decrease soil bioactivities.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Contaminantes del Suelo , Bioensayo , Creosota/análisis , Receptor alfa de Estrógeno , Oxígeno/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Compuestos Policíclicos/análisis , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Vapor/análisis , Azufre
16.
Rapid Commun Mass Spectrom ; 36(20): e9363, 2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-35902380

RESUMEN

RATIONALE: Many methods have been reported for the production of rare ginsenosides, including heat treatment, acid hydrolysis, alkaline hydrolysis, enzymatic hydrolysis, and microbial transformation. However, the conversion of original ginsenosides to rare ginsenosides under the dual conditions of citric acid and high-pressure steam sterilization has rarely been reported. METHODS: In this study, a method involving ultrahigh-performance liquid chromatography coupled to ion mobility quadrupole time-of-flight mass spectrometry was developed for analysis of chemical transformation of protopanaxatriol (PPT)-type ginsenosides Rg1 and Re, protopanaxadiol (PPD)-type ginsenoside Rb1 , and total ginsenosides in the dual conditions of citric acid and high-pressure steam sterilization. An internal ginsenoside database containing 126 known ginsenosides and 18 ginsenoside reference compounds was established to identify the transformation products and explore possible transformation pathways and mechanisms. RESULTS: A total of 54 ginsenosides have been preliminarily identified in the transformation products of PPD-type ginsenosides Rg1 and Re, PPD-type ginsenoside Rb1 , and total ginsenosides, and the possible transformation pathways were as follows: Rg1 , Re → 20(S)-Rh12 , 20(R)-Rh12 ; Rg1 , Re → 20(S)-Rh1 , 20(R)-Rh1 → Rk3 , Rh4 , Rh5 ; Rb1 → gypenoside LXXV; Rb1 → 20(S)-Rg3 , 20(R)-Rg3 → Rk1 , Rg5 ; Re → 20(S)-Rg2 , 20(R)-Rg2 → 20(S)-Rf2 , 20(R)-Rf2 , Rg4 , F4 . CONCLUSIONS: The results elucidated the possible transformation pathways and mechanisms of ginsenosides in the dual conditions of citric acid and high-pressure steam sterilization, which were helpful for revealing the mechanisms of ginsenosides and enhanced safety and quality control of pharmaceuticals and nutraceuticals. Meanwhile, a simple, efficient, and practical method was developed for the production of rare ginsenosides, which has the potential to produce diverse rare ginsenosides on an industrial scale.


Asunto(s)
Ginsenósidos , Panax , Cromatografía Liquida , Ácido Cítrico , Ginsenósidos/química , Espectrometría de Masas , Panax/química , Saponinas , Vapor/análisis , Triterpenos
17.
J Food Biochem ; 46(10): e14326, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35894224

RESUMEN

To improve the performance of potato starch films and solve the problems of high volatility and low stability of thymol (Thy), thymol was loaded into the channel of SBA-15 to prepare Thy-SBA-15, and the Thy-SBA-15/potato starch film was prepared. The results showed thymol was successfully loaded into the pores of SBA-15. The addition of Thy-SBA-15 enhanced the tensile strength of potato starch film (3.93 Mpa), reduced the water vapor permeability (1.56 × 10-12  g·d-1  m-1  Pa-1 , WVP) and moisture absorption (80.97%, MA), which enhanced the barrier properties of the films. Thy-SBA-15 had good compatibility with potato starch films. Notably, the thymol released from Thy-SBA-15/potato starch film was initially explosive, and then continuous, which showed this film could effectively slow down the release rate of thymol and prolong the fresh-keeping period of food. The Korsmeyer-Peppas model M t M ∞ = k t n (R2  > .96) had the best fit for the release curve of thymol. PRACTICAL APPLICATIONS: This work offers a new method for the preparation of potato starch sustained-release antibacterial film, and provides a theoretical basis and technical support for the development of intelligent packaging.


Asunto(s)
Nanocompuestos , Almidón , Antibacterianos , Preparaciones de Acción Retardada , Cinética , Dióxido de Silicio , Vapor/análisis , Timol
18.
Molecules ; 27(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35889468

RESUMEN

To establish the analytic conditions for examining the aroma quality of vanilla pods, we compared different extraction methods and identified a suitable option. We utilized headspace solid-phase microextraction (HS-SPME), steam distillation (SD), simultaneous steam distillation (SDE) and alcoholic extraction combined with gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) to identify volatile components of vanilla pods. A total of 84 volatile compounds were identified in this experiment, of which SDE could identify the most volatile compounds, with a total of 51 species, followed by HS-SPME, with a total of 28 species. Ten volatile compounds were identified by extraction with a minimum of 35% alcohol. HS-SPME extraction provided the highest total aroma peak areas, and the peak areas of aldehydes, furans, alcohols, monoterpenes and phenols compounds were several times higher than those of the other extraction methods. The results showed that the two technologies, SDE and HS-SPME, could be used together to facilitate analysis of vanilla pod aroma.


Asunto(s)
Vanilla , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Odorantes/análisis , Microextracción en Fase Sólida/métodos , Vapor/análisis , Compuestos Orgánicos Volátiles/análisis
19.
Food Chem ; 395: 133605, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-35802976

RESUMEN

In this work, the film-forming properties of chitosan with different molecular weights (MW) (30, 100, 200 and 300 kDa) and its adhesion properties with different postharvest fruit surfaces were analyzed. The viscosity of 30 and 300 kDa chitosan film-forming solution gradually increased from 0.007 to 1.16 Pa.s at a shear rate of 10 s-1. Compared to 30 kDa chitosan films, higher MW chitosan films showed enhanced water resistance, water vapor barrier properties and mechanical properties, mainly due to the different strength of interaction forces within the chitosan films, which can be confirmed by microstructural observations and FTIR results of the films. It can be found that different MW chitosan film surfaces with bananas, apples, pears, oranges and strawberries all have a similar adhesion work of about 70-80 mN m-1, and 100 and 200 kDa chitosan film had higher adhesion work with different fruit surfaces compared to 30 and 300 kDa.


Asunto(s)
Quitosano , Pyrus , Quitosano/química , Frutas/química , Peso Molecular , Vapor/análisis
20.
Meat Sci ; 192: 108881, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35709665

RESUMEN

The aim of the study was to assess the effect of methods of heat treatment on selected quality parameters of longissimus thoracis muscle of Limousin calves, subjected to grilling, steaming, and sous vide cooking. The type of heat treatment did not significantly affect shear force or water activity. Cooking loss in the grilled and steamed meat was significantly higher than in the sous vide. While the content of vitamin E was significantly lower in the cooked meat, it was retained to the greatest degree in the grilled meat and least in the steamed meat. The TBARS index significantly increased during all cooking methods with the highest level in steamed meat. The sensory analysis revealed a preference for the sous vide and grilled meat, while the steamed meat received the lowest scores. Although veal is commonly assumed to be highly nutritious and palatable, its quality can be significantly influenced by the type of heat treatment.


Asunto(s)
Calor , Carne Roja , Animales , Bovinos , Culinaria/métodos , Carne/análisis , Músculos/química , Carne Roja/análisis , Vapor/análisis
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