Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.076
Filtrar
1.
ACS Appl Mater Interfaces ; 16(24): 31399-31406, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38836799

RESUMO

Layered perovskites, a novel class of two-dimensional (2D) layered materials, exhibit versatile photophysical properties of great interest in photovoltaics and optoelectronics. However, their instability to environmental factors, particularly water, has limited their utility. In this study, we introduce an innovative solution to the problem by leveraging the unique properties of natural beeswax as a protective coating of 2D-fluorinated phenylethylammonium lead iodide perovskite. These photodetectors show outstanding figures of merit, such as a responsivity of >2200 A/W and a detectivity of 2.4 × 1018 Jones. The hydrophobic nature of beeswax endows the 2D perovskite sensors with an unprecedented resilience to prolonged immersion in contaminated water, and it increases the lifespan of devices to a period longer than one year. At the same time, the biocompatibility of the beeswax and its self-cleaning properties make it possible to use the very same turbidity sensors for healthcare in photoplethysmography and monitor the human heartbeat with clear systolic and diastolic signatures. Beeswax-enabled multipurpose optoelectronics paves the way to sustainable electronics by ultimately reducing the need for multiple components.


Assuntos
Compostos de Cálcio , Óxidos , Titânio , Ceras , Compostos de Cálcio/química , Titânio/química , Óxidos/química , Ceras/química , Humanos , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Chumbo/química , Chumbo/análise
2.
J Food Sci ; 89(7): 4372-4388, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38837376

RESUMO

High concentrations of carnauba waxes (CRWs) that can compromise organoleptic properties are required to create self-sustained and functional oleogels. The weak physical properties and stability of 4% w/w CRW-rice bran oil (RBO) oleogel were addressed by substituting CRW with beeswax (BW) in different weight ratios. The texture profile analyzer revealed that substituting only 10% (weight ratio) of CRW with BW improved the hardness compared to the mono-CRW oleogel. The hardness of binary oleogels increased gradually as the proportion of BW increased. At a BW ratio of 70% or more, the hardness was three times higher than that of mono-BW oleogel. Rheology analysis showed the same trend as the large deformation test; however, the hardest binary oleogels had lower critical strain and yield point compared to the mono-wax oleogels, implying that they are more prone to lose their structure upon applied stress. Nevertheless, nearly all binary mixtures (except for 10%BW90%CRW) showed oil-binding capacities above 99%, suggesting improved nucleation and crystallization process. Polarized light microscopy showed the coexistence of BW and CRW crystals and changes in the size and arrangement of wax crystals upon proportional changes of the two waxes. X-ray diffraction confirmed no differences in the peaks' location, and all oleogels had ß' polymorphism. Differential scanning calorimetry showed eutectic melting behavior in some binary blends. Oxidation stability in the binary wax oleogels improved as compared to the mono-wax oleogel and bulk RBO. BW and CRW mixtures have promising oil-structuring abilities and have various properties at different ratios that have the potential to be used as solid fat substitutes. PRACTICAL APPLICATION: As a trending green oil-structuring technology, oleogelation has shown great potential to reduce saturated fats in food systems. The current research provides valuable fundamental information on the strong synergistic interactions between beeswax and carnauba wax that have the potential to be used as solid fat substitutes created with a much lower total concentration of the required wax. This will help create wax oleogels with better organoleptic properties and less negative waxy mouthfeel. Such knowledge could prove beneficial for the development of healthy products that have potential applications in meat, bakery, dairy, pharmaceutical, as well as cosmetic industries.


Assuntos
Compostos Orgânicos , Oxirredução , Reologia , Ceras , Ceras/química , Compostos Orgânicos/química , Difração de Raios X
3.
Food Res Int ; 188: 114475, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823838

RESUMO

This work aimed to develop edible emulsion-based barriers in the form of chitosan composite films, with a focus on assessing the impacts of carnauba wax, rosin resin, and zinc oxide nanoparticles on their properties. Six films were produced by casting using chitosan as polymer base and glycerol as plasticizer. Acetic acid and polysorbate 80 were also used to facilitate the dissolution and mixing of the components. The six filmogenic solutions contained chitosan at 1.2% w/v, wax or resin content with 0 or 0.6% m/v and ZnO with 0 or 0.05% m/v. The dried films were characterized according to their chemical, barrier, mechanical, thermal and optical properties. All treatments resulted in flexible films. Chitosan films appeared smoother and more uniform under SEM imaging, while carnauba wax films displayed roughness due to their hydrophobic nature. Wax and resin films were less transparent and water soluble than the chitosan-only films. On the other hand, the addition of ZnO in the formulations increased the solubility of the films. The sorption degree was in line with the solubility results, i.e., films with ZnO presented higher sorption degree and solubility values. All treatments showed low or non-light UV transmission, indicating that the films provide good barrier to UV light. In the visible light region, films of resin with ZnO showed the lowest transmittance values, hence offering a good barrier to visible light. Among the evaluated films, chitosan, and resin films with ZnO nanoparticles were more rigid and resistant to deformation. Overall, films produced with rosin resin and ZnO nanoparticles showed potential improvements in barrier, mechanical, thermal, and optical properties, mainly due to their low water solubility, good UV protection and low permeability to water vapor and oxygen, which are suitable for using in formulations, intended to produce edible films and coatings.


Assuntos
Quitosana , Nanocompostos , Resinas Vegetais , Solubilidade , Ceras , Óxido de Zinco , Quitosana/química , Óxido de Zinco/química , Nanocompostos/química , Resinas Vegetais/química , Ceras/química , Nanopartículas/química , Embalagem de Alimentos/métodos , Permeabilidade
4.
Anal Chim Acta ; 1314: 342754, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38876512

RESUMO

The unique properties of per- and polyfluoroalkyl substances (PFAS) have led to their extensive use in consumer products, including ski wax. Based on the risks associated with PFAS, and to align with PFAS regulations, the international ski federation (FIS) implemented a ban on products containing "C8 fluorocarbons/perfluorooctanoate (PFOA)" at all FIS events from the 2021/2022 season, leading manufactures to shift their formulations towards short-chain PFAS chemistries. To date, most studies characterising PFAS in ski waxes have measured a suite of individual substances using targeted analytical approaches. However, the fraction of total fluorine (TF) in the wax accounted for by these substances remains unclear. In this study, we sought to address this question by applying a multi-platform, fluorine mass balance approach to a total of 10 commercially available ski wax products. Analysis of TF by combustion ion chromatography (CIC) revealed concentrations of 1040-51700 µg F g-1 for the different fluorinated waxes. In comparison, extractable organic fluorine (EOF) determined in methanol extracts by CIC (and later confirmed by inductively-coupled plasma-mass spectrometry and 19F- nuclear magnetic resonance spectroscopy) ranged from 92 to 3160 µg g-1, accounting for only 3-8.8 % of total fluorine (TF). Further characterisation of extracts by cyclic ion mobility-mass spectrometry (IMS) revealed 15 individual PFAS with perfluoroalkyl carboxylic acid concentrations up to 33 µg F g-1, and 3 products exceeding the regulatory limit for PFOA (0.025 µg g-1) by a factor of up to 100. The sum of all PFAS accounted for only 0.01-1.0 % of EOF, implying a high percentage of unidentified PFAS, thus, pyrolysis gas chromatography-mass spectrometry was used to provide evidence of the nature of the non-extractable fluorine present in the ski wax products.


Assuntos
Flúor , Fluorocarbonos , Ceras , Fluorocarbonos/análise , Fluorocarbonos/química , Flúor/análise , Flúor/química , Ceras/química , Ceras/análise , Caprilatos/análise , Caprilatos/química
5.
Food Res Int ; 189: 114579, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876599

RESUMO

Utilizing waxes to gel oils presents a viable approach for diminishing trans and saturated fat levels in commercial fats such as margarines. This technique ensures that oleogels mimic traditional fats in terms of rheological properties, oil-binding capacity, and overall structure. Our study employed cooling-shear rates to finely adjust physical characteristics, evaluating rheology via SAOS-LAOS, oil retention, and crystal structure of wax oleogels, compared against commercial margarines as benchmarks. Findings indicate that wax oleogels, under specific cooling/shear conditions, exhibit softer yet more ductile-like behavior, akin to margarine, while retaining oil effectively. This similarity is evidenced through Lissajous curves and plastic dissipation ratio during yielding, reflecting a ductile yielding response characterized by square-like Lissajous curves and a plastic dissipation ratio index approximating one. Although these crystallization conditions influence the mechanical properties of wax oleogels, they do not alter oil losses or wax characteristics.


Assuntos
Margarina , Compostos Orgânicos , Reologia , Ceras , Ceras/química , Compostos Orgânicos/química , Margarina/análise , Cristalização
6.
Theor Appl Genet ; 137(6): 123, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722407

RESUMO

KEY MESSAGE: BrBCAT1 encoding a branched-chain amino acid aminotransferase was responsible for the glossy trait, which was verified by allelic mutants in Chinese cabbage. The glossy characteristic, thanks to the epicuticular wax crystal deficiency, is an excellent commodity character for leafy vegetables. Herein, two allelic glossy green mutants, wdm11 and wdm12, were isolated from an ethyl methane sulfonate (EMS)-mutagenized population of Chinese cabbage, and the mutant phenotype was recessive inherited. Cryo-SEM detected that epicuticular wax crystal in the mutant leaves was virtually absent. MutMap and Kompetitive allele-specific PCR analyses demonstrated that BraA06g006950.3C (BrBCAT1), homologous to AtBCAT1, encoding a branched-chain amino acid aminotransferase was the candidate gene. A SNP (G to A) on the fourth exon of BrBCAT1 in wdm11 caused the 233rd amino acid to change from glycine (G) to aspartic acid (D). A SNP (G to A) on the second exon of BrBCAT1 in wdm12 led to the 112th amino acid change from glycine (G) to arginine (R). Both of the allelic mutants had genetic structural variation in the candidate gene, which indicated that the mutant phenotype was triggered by the BrBCAT1 mutation. The expression levels of BrBCAT1 and genes related to fatty acid chain extension were decreased significantly in the mutant compared to the wild-type, which might result in epicuticular wax crystal deficiency in the mutants. Our findings proved that the mutation of BrBCAT1 induced the glossy phenotype and provided a valuable gene resource for commodity character improvement in Chinese cabbage.


Assuntos
Brassica , Folhas de Planta , Transaminases , Ceras , Alelos , Brassica/genética , Mutação , Fenótipo , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Polimorfismo de Nucleotídeo Único , Transaminases/genética , Ceras/química , Ceras/metabolismo
7.
Int J Biol Macromol ; 272(Pt 1): 132532, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38806082

RESUMO

The study involved preparing and applying edible nano-emulsion coatings containing hydroxypropyl methylcellulose (HPMC), beeswax (BW), and essential oils (thyme, cinnamon, clove, and peppermint) onto sweet cherries. The application was conducted at 4 °C, and the coated cherries were stored for 36 days. This research examines synthesized nano-emulsions physicochemical properties and antibacterial and antifungal activities (C1, C2, and C3). Additionally, it evaluates the quality parameters of control and coated sweet cherry samples. The features of the three edible coatings were assessed, and the findings from the zeta sizer, zeta potential, FTIR, and SEM analyses were deemed satisfactory. It was observed that the application of nano-emulsion coating C1 yielded positive results in maintaining quality attributes such as total suspended solids (TSS), total solids (TS), color, weight loss, respiration rate, firmness, total phenolic contents, and sensory evaluations. Nano-emulsion coating C1 demonstrated efficacy as an antibacterial and antifungal agent against foodborne pathogens E. coli and A. niger, respectively. The current research results are promising and applicable in food industries. The implications suggest that composite nano-emulsion, specifically nano-emulsion edible coatings, can be extensively and effectively used to preserve the quality and shelf life of fruits and vegetables. Furthermore, the environmental waste from conventional food packaging will be minimized using edible packaging applications.


Assuntos
Derivados da Hipromelose , Óleos Voláteis , Ceras , Ceras/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Derivados da Hipromelose/química , Antibacterianos/farmacologia , Antibacterianos/química , Conservação de Alimentos/métodos , Armazenamento de Alimentos , Emulsões , Cymbopogon/química , Filmes Comestíveis , Antifúngicos/farmacologia , Antifúngicos/química , Escherichia coli/efeitos dos fármacos , Frutas/química
8.
Food Chem ; 454: 139663, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38797103

RESUMO

Oleogels have been explored as a new lipid-based delivery system, however, their insolubility and unsuitable shape severely limit their application in food systems. Herein, core-shell oleogel capsules with high monodispersity (coefficient variation (CV) < 5%)) were prepared via gravity-assisted co-flowing microfluidic device and simply air-drying. The oleogel capsules with oleogel core and ultrathin calcium-alginate shell were prepared. Oleogel capsules maintained their original shape at pH = 2.0 but swelled rapidly at pH = 6.8 and 7.4. The swelling ratio of shell can be adjusted by inner fluid flow rate (Qin). Notably, the core with beeswax (BW) crystal network, effectively improved the stability performances and also could provide thermal response. Finally, the oleogel capsules demonstrated excellent sustained release and UV protection of lipophilic bioactives. This work sheds light on development of novel oleogel capsules, making them ideal candidates for smart food encapsulation applications.


Assuntos
Alginatos , Cápsulas , Compostos Orgânicos , Alginatos/química , Cápsulas/química , Compostos Orgânicos/química , Concentração de Íons de Hidrogênio , Temperatura , Ceras/química
9.
Int J Biol Macromol ; 271(Pt 2): 132592, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38820905

RESUMO

Torreya grandis wax (TGW), a new nut wax and by-product of refined Torreya grandis oil, lacks sufficient research and application. In this study, the gelling behavior in diacylglycerol (DAG) and chemical compositions of TGW were investigated. Compared with four typical natural waxes, TGW exhibited the lowest critical gelling concentration (Cg, 1 %wt) in DAG. The results performed that TGW-DAG oleogels at Cg possessed the highest G'LVR and G″, highest critical stress, good thermal stability, moderate viscosity recovery, and osc. yields stress, indicating strong gel. The microstructure and correlation analysis revealed that excellent gelling behaviors of TGW-DAG oleogels were due to the solid three-dimensional network formed by rod-like TGW crystal, and the higher hydrocarbon compound (HC) content and HC/wax ester in TGW. Formulation optimization suggested that oleogel containing 3.2 % TGW and 1.0 % diosgenin (DSG) better mimicked the characteristics of shortening in terms of hardness, adhesiveness, spreadability. The bread prepared with TGW/DSG-DAG oleogel owned uniform and dense pores, the best moisture retention capability, and soft and firm taste, demonstrating that TGW/DSG-DAG oleogel was a good shortening substitute. Therefore, this study provides the systematically fundamental knowledge of TGW and develops DSG-TGW-DAG oleogels as promising shortening substitutions.


Assuntos
Diglicerídeos , Géis , Compostos Orgânicos , Ceras , Ceras/química , Diglicerídeos/química , Compostos Orgânicos/química , Géis/química , Viscosidade , Reologia
10.
Open Biol ; 14(5): 230430, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38806146

RESUMO

Both leaves and petals are covered in a cuticle, which itself contains and is covered by cuticular waxes. The waxes perform various roles in plants' lives, and the cuticular composition of leaves has received much attention. To date, the cuticular composition of petals has been largely ignored. Being the outermost boundary between the plant and the environment, the cuticle is the first point of contact between a flower and a pollinator, yet we know little about how plant-pollinator interactions shape its chemical composition. Here, we investigate the general structure and composition of floral cuticular waxes by analysing the cuticular composition of leaves and petals of 49 plant species, representing 19 orders and 27 families. We show that the flowers of plants from across the phylogenetic range are nearly devoid of wax crystals and that the total wax load of leaves in 90% of the species is higher than that of petals. The proportion of alkanes is higher, and the chain lengths of the aliphatic compounds are shorter in petals than in leaves. We argue these differences are a result of adaptation to the different roles leaves and petals play in plant biology.


Assuntos
Flores , Folhas de Planta , Ceras , Folhas de Planta/química , Folhas de Planta/metabolismo , Ceras/química , Ceras/metabolismo , Flores/química , Flores/metabolismo , Filogenia , Epiderme Vegetal/química , Epiderme Vegetal/metabolismo , Plantas/química , Plantas/metabolismo , Especificidade da Espécie
11.
Anal Methods ; 16(21): 3372-3384, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38747244

RESUMO

Microfluidic channels fabricated over fabrics or papers have the potential to find substantial application in the next generation of wearable healthcare monitoring systems. The present work focuses on the fabrication procedures that can be used to obtain practically realizable fabric-based microfluidic channels (µFADs) utilizing patterning masks and wax, unlike conventional printing techniques. In this study, comparative analysis was used to differentiate channels obtained using different masking tools for channel patterning as well as different wax materials as hydrophobic barriers. Drawbacks of the conventional tape and candle wax technique were noted and a novel approach was used to create microfluidic channels through a facile and simple masking technique using PVC clear sheets as channel stencils and beeswax as the channel barriers. The resulting fabric based microfluidic channels with varying widths as well as complex microchannel, microwell, and micromixer designs were investigated and a minimum channel width resolution of 500 µm was successfully obtained over cotton based fabrics. Thereafter, the PVC clear sheet-beeswax based microwells were successfully tested to confine various organic and inorganic samples indicating vivid applicability of the technique. Finally, the microwells were used to make a simple and facile colorimetric assay for glucose detection and demonstrated effective detection of glucose levels from 10 mM to 50 mM with significant color variation using potassium iodide as the coloring agent. The above findings clearly suggest the potential of this alternative technique for making low-cost and practically realizable fabric based diagnostic devices (µFADs) in contrast to the other approaches that are currently in use.


Assuntos
Cloreto de Polivinila , Têxteis , Ceras , Ceras/química , Cloreto de Polivinila/química , Colorimetria/métodos , Colorimetria/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Análise Custo-Benefício , Glucose/análise , Dispositivos Lab-On-A-Chip , Humanos , Desenho de Equipamento , Dispositivos Eletrônicos Vestíveis
12.
J Agric Food Chem ; 72(21): 11990-12002, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757490

RESUMO

The main challenge in the development of agrochemicals is the lack of new leads and/or targets. It is critical to discover new molecular targets and their corresponding ligands. YZK-C22, which contains a 1,2,3-thiadiazol-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole skeleton, is a fungicide lead compound with broad-spectrum fungicidal activity. Previous studies suggested that the [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole scaffold exhibited good antifungal activity. Inspired by this, a series of pyrrolo[2,3-d]thiazole derivatives were designed and synthesized through a bioisosteric strategy. Compounds C1, C9, and C20 were found to be more active against Rhizoctonia solani than the positive control YZK-C22. More than half of the target compounds provided favorable activity against Botrytis cinerea, where the EC50 values of compounds C4, C6, C8, C10, and C20 varied from 1.17 to 1.77 µg/mL. Surface plasmon resonance and molecular docking suggested that in vitro potent compounds C9 and C20 have a new mode of action instead of acting as pyruvate kinase inhibitors. Transcriptome analysis revealed that compound C20 can impact the tryptophan metabolic pathway, cutin, suberin, and wax biosynthesis of B. cinerea. Overall, pyrrolo[2,3-d]thiazole is discovered as a new fungicidal lead structure with a potential new mode of action for further exploration.


Assuntos
Botrytis , Fungicidas Industriais , Rhizoctonia , Tiazóis , Triptofano , Ceras , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/síntese química , Rhizoctonia/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Tiazóis/farmacologia , Tiazóis/química , Tiazóis/metabolismo , Triptofano/metabolismo , Triptofano/química , Ceras/química , Ceras/metabolismo , Relação Estrutura-Atividade , Redes e Vias Metabólicas/efeitos dos fármacos , Simulação de Acoplamento Molecular , Pirróis/farmacologia , Pirróis/química , Pirróis/metabolismo , Doenças das Plantas/microbiologia , Estrutura Molecular
13.
Food Chem ; 453: 139680, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38788648

RESUMO

Hydrophobic coatings have wide applications, but face challenges in food flexible packaging in terms of poor adhesion and inadequate wear resistance. Health hazards and poor adhesion drive the search for novel hydrophobic coatings substitutes. Here, we introduced rationally synthesized carnauba wax-SiO2 microspheres as a component to composite polyethylene (PE) film construction, and created a wear-resistant hydrophobic composite PE film via the blown film technique. The resultant hydrophobic composite film demonstrated an enhanced water contact angle from 86° to above 100°, coupled with favorable mechanical properties such as wear resistance, tensile strength and effective barrier performance against water vapor and oxygen. Upon implementation in the preservation of a Cantonese delicacy, Chaoshan fried shrimp rolls, it was observed that at 25 °C, the carnauba wax-SiO2-PE composite packaging film extended the shelf life of the product by 3 days compared to pure PE film.


Assuntos
Embalagem de Alimentos , Conservação de Alimentos , Interações Hidrofóbicas e Hidrofílicas , Polietileno , Ceras , Polietileno/química , Embalagem de Alimentos/instrumentação , Animais , Ceras/química , Conservação de Alimentos/métodos , Conservação de Alimentos/instrumentação , Resistência à Tração , Dióxido de Silício/química , Penaeidae/química
14.
J Food Sci ; 89(5): 2943-2955, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38557930

RESUMO

Bell pepper presents rapid weight loss and is highly susceptible to gray mold caused by the fungus Botrytis cinerea. The most employed method to control this disease is the application of synthetic fungicides such as thiabendazole (TBZ); however, its continued use causes resistance in fungi as well as environmental problems. For these reasons, natural alternatives arise as a more striking option. Currently, bell pepper fruits are coated with carnauba wax (CW) to prevent weight loss and improve appearance. Moreover, CW can be used as a carrier to incorporate essential oils, and previous studies have shown that thyme essential oil (TEO) is highly effective against B. cinerea. Therefore, this study aimed to evaluate the effect of CW combined with TEO on the development of gray mold and maintenance of microestructural and postharvest quality in bell pepper stored at 13°C. The minimal inhibitory concentration of TEO was 0.5%. TEO and TBZ provoked the leakage of intracellular components. TEO and CW + TEO treatments were equally effective to inhibit the development of gray mold. On the quality parameters, firmness and weight loss were ameliorated with CW and CW + TEO treatments; whereas lightness increased in these treatments. The structural analysis showed that CW + TEO treatment maintained the cell structure reducing the apparition of deformities. The results suggest that CW + TEO treatment could be used as a natural and effective antifungal retarding the appearance of gray mold and maintaining the postharvest quality of bell pepper. PRACTICAL APPLICATION: CW and TEO are classified as generally recognized as safe (GRAS) by the US Food and Drug Administration (FDA). This combination can be employed on the bell pepper packaging system to extend shelf life and oppose gray mold developments. Bell pepper fruits are normally coated with lipid-base coatings such as CW before commercialization; therefore, TEO addition would represent a small investment without any changes on the packaging system infrastructure.


Assuntos
Botrytis , Capsicum , Conservação de Alimentos , Frutas , Óleos Voláteis , Thymus (Planta) , Ceras , Botrytis/efeitos dos fármacos , Capsicum/microbiologia , Capsicum/química , Thymus (Planta)/química , Óleos Voláteis/farmacologia , Ceras/química , Ceras/farmacologia , Conservação de Alimentos/métodos , Frutas/microbiologia , Frutas/química , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Fungicidas Industriais/farmacologia
15.
Food Chem ; 449: 139234, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608604

RESUMO

Cuticle wax chemicals are cultivar-dependent and contribute to storage quality. Few research reported on wax analysis between melting flesh-type (MF; 'Jinhuami 25') and nonmelting flesh-type (NMF; 'Xizhoumi 17' and 'Chougua') Hami melons. Chemicals and crystal structures of Hami melon cuticular wax, cell wall metabolism related to fruit melting, and fruit physiology were analyzed to observe wax functions. Results showed that Hami melon cuticle wax predominantly consists of esters, alkanes, alcohols, aldehydes, and terpenoids. MF-type has a lower alkane/terpenoid ratio, concomitant to its higher weight loss and cuticle permeability. Micromorphology of wax crystals appears as numerous platelets with irregular crystals, and the transformation of wax structure in NMF Hami melon is delayed. Waxy components affect cell wall metabolism and physiological quality, which results in the pulp texture difference between MF-type and NMF-type during storage. Results provide a reference for the regulation of wax synthesis in both types of melons.


Assuntos
Cucumis melo , Frutas , Ceras , Ceras/química , Frutas/química , Cucumis melo/química , Parede Celular/química
16.
Food Chem ; 450: 139334, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38636379

RESUMO

We investigated the ripening and skin greasiness of "Hongro" apples during storage at 20 °C. Postharvest treatment using 100 µLL-1 ethylene accelerated ripening and increased greasiness, whereas treatment using 1 µLL-1 1-methylcyclopropene delayed ripening and reduced greasiness. Scanning electron microscopy showed changes in cuticular wax structure linked to greasiness. Metabolic analysis identified specific metabolites related to greasiness, which varied upon postharvest treatment. Greasiness was positively associated with ethylene production and butyl-9,12-octadecadienoate content. Random forest modeling predicted greasiness levels with high accuracy, with root mean square error values of 0.322 and 0.362 for training and validation datasets, respectively. These findings illuminate the complex interplay between postharvest treatment, apple ripening, wax composition, and skin greasiness. The application of predictive models exemplifies the potential for technology-driven approaches in agriculture and aids in the development of postharvest strategies to control greasiness and maintain fruit quality.


Assuntos
Frutas , Malus , Ceras , Malus/química , Malus/metabolismo , Malus/crescimento & desenvolvimento , Frutas/química , Frutas/metabolismo , Frutas/crescimento & desenvolvimento , Ceras/química , Ceras/metabolismo , Armazenamento de Alimentos , Etilenos/química , Etilenos/metabolismo
17.
J Sci Food Agric ; 104(10): 6157-6165, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38456778

RESUMO

BACKGROUND: Solid fats are critical to obtaining a wide range of food texture and quality characteristics, but their consumption is strongly associated with higher cardiovascular disease risks. Structuring unsaturated oils with natural waxes into oleogels (OG) is an innovative solution to develop fat mimics with a healthier profile. RESULTS: Soy wax (SW), beeswax (BW) and carnauba wax (CW), have been used in binary mixtures of waxes, aiming to understand their interactions and influence on OG quality properties and microstructural characteristics. In the present study, OGs were produced using binary wax mixtures and analyzed for texture, color, smoke point, microstructure, Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Wax combinations led to antagonistic (mixtures with SW) and synergistic interactions (BW/CW) based on their mechanical properties. At the microstructural level BW/CW blends showed a reduction in crystal size and with a more compact structure. XRD and FTIR spectra revealed a packing of orthorhombic perpendicular subcell for most OGs, whereas SW produced samples with an arrangement with ß' crystals, characteristic of edible solid fats. Additionally, when compared to commercial beef fat, BW/CW mixtures showed similar quality attributes indicating that they could act as fat mimic. CONCLUSION: The combined analysis of microstructure, spectroscopic and mechanical properties enhanced the understanding of how the nature of the interactions between waxes and lipid phases impact in the final quality of the structured oils. The study's insights indicate that binary wax combinations can efficiently replace solid fats, offering healthier alternatives at the same time as preserving desired sensory characteristics. © 2024 Society of Chemical Industry.


Assuntos
Compostos Orgânicos , Ceras , Ceras/química , Compostos Orgânicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
18.
Food Res Int ; 182: 114178, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519192

RESUMO

To explore the feasibility of substituting waxy rice with waxy or sweet-waxy corn, eight varieties of waxy and sweet-waxy corns were selected, including three self-cultivated varieties (Feng nuo 168, Feng nuo 211, and Feng nuo 10). Their starches were isolated and used as research objects, and commercially available waxy rice starch (CAWR) and waxy corn starch (CAWC) were used as controls. X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, rapid viscosity analyzer, and rotational rheometer were used to analyze their physicochemical and structural characteristics. The morphologies of all corn starch granules were generally oval or round, with significant differences in particle size distributions. All ten starches exhibited a typical A-type crystal structure; however, their relative crystallinity varied from 20.08% to 31.43%. Chain length distribution analysis showed that the A/B ratio of Jing cai tian nuo 18 and Feng nuo 168 was similar to that of CAWR. Peak viscosities of corn starches were higher than that of CAWR, except for Feng nuo 10, while their setback values were lower than that of CAWR. Except for Feng nuo 10, the paste transparency of corn starches was higher than that of CAWR (10.77%), especially for Jing cai tian nuo 18 (up to 24%). In summary, Jing cai tian nuo 18 and Feng nuo 168 are promising candidates to replace CAWR in developing various rice-based products.


Assuntos
Oryza , Zea mays , Zea mays/química , Oryza/química , Ceras/química , Estudos de Viabilidade , Amido/química , Amilopectina/química
19.
Drug Dev Ind Pharm ; 50(5): 432-445, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38526993

RESUMO

OBJECTIVE: The purpose of this research was to determine any connections between the characteristics of oleogels made of beeswax and the impact of mango butter. METHODS: Oleogel was prepared through inverted tube methods, and optimized through oil binding capacity. Other evaluations like bright field and polarized microscopy, Fourier-transform infrared (FTIR) spectroscopy, crystallization kinetics, mechanical study, and X-ray diffractometry (XRD). The drug release kinetic studies and in vitro antibacterial studies were performed. RESULTS: FTIR study reveals that the gelation process does not significantly alter the chemical composition of the individual components. Prepared gel exhibiting fluid-like behavior or composed of brittle networks is particularly vulnerable to disruptions in their network design. The incorporation of mango butter increases the drug permeation. In-vitro microbial efficacy study was found to be excellent. CONCLUSION: The studies revealed that mango butter can be used to modify the physico-chemical properties of the oleogels.


Assuntos
Mangifera , Compostos Orgânicos , Óleos de Plantas , Ceras , Ceras/química , Mangifera/química , Compostos Orgânicos/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Sementes/química , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Administração Tópica , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Liberação Controlada de Fármacos
20.
J Nat Prod ; 87(4): 954-965, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38547477

RESUMO

The tear film lipid layer (TFLL) plays a vital part in maintenance of ocular health and represents a unique biological barrier comprising unusual and specialized lipid classes and species. The wax and cholesteryl esters (WEs and CEs) constitute roughly 80-90% of the TFLL. The majority of species in these lipid classes are branched and it is therefore surprising that the synthesis and properties of the second largest category of species, i.e., the anteiso-branched species, remain poorly characterized. In this study, we have developed a total synthesis route and completed a detailed NMR spectroscopic characterization of two common anteiso-branched species, namely: (22S)-22-methyltetracosanyl oleate and cholesteryl (22'S)-22'-methyltetracosanoate. In addition, we have studied their structural properties in the bulk state by wide-angle and small-angle X-ray scattering and their behavior at the aqueous interface using Langmuir monolayer techniques. A comparison to the properties displayed by iso-branched and straight-chain analogues indicate that branching patterns lead to distinct properties in the CE and WE lipid classes. Overall, this study complements the previous work in the field and adds another important brick in the tear film insights wall.


Assuntos
Ésteres do Colesterol , Lágrimas , Ceras , Ésteres do Colesterol/química , Ésteres do Colesterol/síntese química , Lágrimas/química , Ceras/química , Estrutura Molecular , Espectroscopia de Ressonância Magnética , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...