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1.
Front Plant Sci ; 15: 1278538, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344189

RESUMO

Introduction: Phytophthora infestans, the causative agent of late blight disease, has gained notoriety for its destructive potential, leading to substantial losses in potato yields. Although conventional systemic fungicides have been shown to be effective in controlling plant pathogens, growing environmental concerns have prompted the need for more integrated disease management approaches. Hence, in this study, the effectiveness of wild Origanum elongatum extracts as biopesticides was explored in controlling P. infestans and potentially mitigating its devastating impact in planta. Methods: The aerial parts of O. elongatum were subjected to sequential extraction using water, hexane, chloroform, and methanol. The obtained extracts were tested in vitro through the poisoned food procedure for their capacity to obstruct P. infestans growth and to defeat potato blight severity in vivo. The phyto-contents (total phenolic content (TPC) and total flavonoid content (TFC)), as well as the antioxidant activities, were spectrophotometrically determined in all extracts, and the phytoconstituents of the most active extract (methanolic extract) were profiled via high-performance liquid chromatography-photodiode array-tandem mass spectrometry (HPLC-PDA-MS/MS). Results: In vitro, the complete inhibition rate of the P. infestans was obtained using the methanolic extract at 5 mg/mL, followed by the hexane and chloroform extracts at 10 mg/mL. Interestingly, complete inhibition of the pathogen was achieved upon the application of the aqueous extract at 10 mg/mL. In vivo, the aqueous extract at 25 mg/mL reduced the P. infestans severity rate to 27.25%, while the methanolic extract at 20 mg/mL led to the lowest severity rate. Moreover, the hexane and chloroform extracts impaired the pathogen severity rate to 50% and 41% using 20 mg/mL, respectively. The TPC and TFC in the extracts were variable with high concentrations detected in the methanolic extract with 485.42 mg GAE/g and 58.24 mg QE/g, respectively. In addition, the methanolic extract showed the highest antioxidant activities, while the chloroform extract exhibited the lowest activity. Liquid chromatography (LC)-MS/MS analysis of the methanol extract revealed 56 components from diverse classes. These included organic acids, phenolic acids, flavonoids, tannins, and coumarins. Conclusion: These findings suggest that O. elongatum could be investigated as a potential source of antifungal compounds targeting different phytopathogens.

2.
Heliyon ; 9(9): e19677, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809870

RESUMO

The surface activity of γ-oryzanol was evaluated by the pendant drop method (PDM), and its self-stabilizing properties were investigated by high-pressure homogenization (HPH) and solvent displacement method (SDM). Emulsions prepared by HPH were highly unstable due to the poor surface-active character of γ-oryzanol as identified by the PDM. In contrast, solid dispersions fabricated by SDM had comparable particle size to those prepared using Tween 80 (T80) as surfactant, and were stable up to 30 days of storage at 4 °C. The self-stabilizing properties of γ-oryzanol were attributed to the mechanism of spontaneous particle formation in SDM and to the ability of γ-oryzanol molecules to prevent particles aggregation by electrostatic repulsion. The outcome of this study indicates the potential of encapsulating selected bioactive compounds, such as γ-oryzanol, in stable colloidal systems by SDM without adding emulsifier(s), regardless of their surface-active character.

3.
Foods ; 12(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37048242

RESUMO

This study aimed to improve the visual aspects and chemical, techno-functional and rheological characteristics of Gryllus bimaculatus cricket powder through the use of different solvents, with the objective of using it as a protein source in food production. Four treatments (pH 5 aqueous solution, ethanol 20%, ethanol 99.5%, and hexane) were applied to the powder, and analyses were conducted to assess changes in the previously mentioned parameters. The results showed that the treatments led to an increase in protein concentration (from 55.4 to 72.5%) and a decrease in fat concentration (from 33.0 to 6.8%) in ethanol 99.5% treated powder, as well as a reduction in anti-nutritional compounds concentration, such as tannins (from 13.3 to 5.9 g/kg), in pH 5 treated powder, which is important for the nutritional value of the final product. The color of the powders was improved, being lighter after hexane and ethanol 99.5% treatments due to the removal of melanin with the defatting process. Flowability, water, and oil holding capacity were also improved in the defatted powders. All the results suggest that the main composition of the powder directly influences the analyzed parameters. These findings suggest that cricket powder treated with solvents can be used as a protein source in different food applications.

4.
Sci Total Environ ; 870: 162001, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36739012

RESUMO

Africa benefits from diverse biomasses that are rich in high-added value materials and precursors for energy, food, agricultural, cosmetic and medicinal applications. Many African countries are interested in valorizing biomasses to develop efficient and integrated biorefinery processes and their use for local and regional economic development. Thus, this report critically reviews the current status of African biomass richness, its diversity, and potential applications. Moreover, particular attention is given to bioenergy production, mainly by biological and thermochemical conversion processes. This also includes biomass valorization in agriculture, particularly for the production of plant-based biostimulants, which are a potential emerging agri-input sector worldwide. This study points out that even though several processes for biofuel, biogas, biofertilizer and biostimulant production have already been established in Africa, their development on a larger scale remains limited. This study also reports the different socioeconomic and political aspects of biomass applications, along with their challenges, opportunities, and future research perspectives, to promote concrete technologies transferable into an industrial level.


Assuntos
Desenvolvimento Econômico , Indústrias , Biomassa , Agricultura , Tecnologia , Biocombustíveis
5.
Molecules ; 28(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36770704

RESUMO

For many decades, natural resources have traditionally been employed in skin care. Here, we explored the phytochemical profile of the aqueous and ethanolic leaf extracts of Cupressus arizonica Greene and assessed their antioxidant, antiaging and antibacterial activities in vitro. Liquid chromatography-mass spectrometry (LC-MS/MS) analysis led to the tentative identification of 67 compounds consisting mainly of phenolic and fatty acids, diterpene acids, proanthocyanidins and flavonoid and biflavonoid glycosides. The aqueous extract demonstrated substantial in vitro antioxidant potential at FRAP and DPPH assays and inhibited the four target enzymes (collagenase, elastase, tyrosinase, and hyaluronidase) engaged in skin remodeling and aging with IC50 values close to those of the standard drugs. Moreover, the aqueous extract at 25 mg/mL suppressed biofilm formation by Pseudomonas aeruginosa, a bacterial pathogen causing common skin manifestations, and decreased its swarming and swimming motilities. In conclusion, C. arizonica leaves can be considered a promising candidate for potential application in skin aging.


Assuntos
Cosmecêuticos , Cupressaceae , Cupressus , Antioxidantes/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Extratos Vegetais/química
6.
J Food Sci Technol ; 59(11): 4427-4435, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36193465

RESUMO

In this study, we evaluated the caprylic acid-based oil-in-water (O/W) emulsion-assisted extraction of lycopene from tomatoes. Emulsion-assisted extraction was performed using two types of micron-sized O/W emulsions: (a) O/W emulsion with absence or (b) presence of 0.1% (w/w) of Tween 20 emulsifier. This green extraction technique was compared with the conventional method using soybean oil, tributyrin, and caprylic acid. The results show that caprylic acid, a green solvent, is significantly more effective for lycopene recovery than soybean oil and tributyrin. In the absence of an emulsifier, caprylic acid-based O/W emulsion significantly improved the lycopene content by 14.69 mg/g, corresponding to a 98.59% extraction efficiency at 50 ˚C. The capability of the proposed approach to lycopene recovery was explained in terms of lycopene affinity, the ability to swell the tomato cell, and some other standard parameters. In addition, caprylic acid has the significant advantage that once developed with the extracted lycopene can be used directly as a food additive.

7.
Food Res Int ; 153: 110894, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35227489

RESUMO

Alpha-terpineol (α-TOH) is a promising monoterpenoid detaining several biological activities. However, as a volatile molecule, the incorporation of α-TOH within formulated products poses several challenges related to its stability. In this sense, nanoencapsulation works as a key technology to protect the bioactivity of low molecular weight oils, like α-TOH, against environmental stresses (heat, light, and moisture), mitigating their susceptibility to degradation (oxidation and volatilization). Physical properties of encapsulated flavor/essential oil have been extensively reported, whereas there is a lack in the literature regarding their chemical stability, which is usually the main purpose of encapsulation. Thus, in this study, the physicochemical stability of the formulated oil-in-water nanoemulsion loaded with α-TOH stabilized with Quillaja saponins (QSs) as a natural emulsifier (α-TOH-QSs-NE) were tracked in a long-term (up to 280th day). Along with time, mean droplet diameter (MDD) and turbidity were used as a reference for physical parameters; while the chemical stability was monitored using gas chromatography analysis to quantify the mark content of α-TOH into the NE. Results indicated that α-TOH-QSs-NE was successfully formulated with a high-load amount of α-TOH (90 mg mL-1). α-TOH-QSs-NE showed great physicochemical stability regardless the storage-temperature (5 °C or 25 °C) up to 280th day, with no significant alterations in the MDD or turbidity, where c.a. 79% of the initial amount of the nanoemulsified α-TOH remained detectable in α-TOH-QSs-NEs, with no finding of degradation products. Thus, the data here disclosure may be useful for innovative application of α-TOH in foodstuffs.


Assuntos
Óleos , Água , Monoterpenos Cicloexânicos , Emulsões/química , Óleos/química , Saponinas de Quilaia/química , Água/química
8.
Food Chem ; 382: 132300, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35134726

RESUMO

Concentrated γ-Oryzanol nanodispersions were fabricated using milli-Q water (no emulsifier) or 0.1% (w/w) polysorbate 80 (T80), modified lecithin (ML) or sodium caseinate (SC) as emulsifiers. The freshly prepared nanodispersions had comparable particle diameter (118 to 157 nm), γ-Oryzanol concentration (1.75 to 1.92 mg mL-1) and free-radical scavenging activity (59 to 62%) and had negative ζ-potentials (-22 to -59 mV), indicating that both γ-Oryzanol and emulsifier coexisted on the particles' interface. The nanoparticles had superior physicochemical stability up to 30 days of storage at 5 °C and were successfully autoclaved without excessive growth or aggregation. Nevertheless, they showed distinct physical stability upon storage at specific environmental conditions, which affected their In-vitro gastrointestinal digestion. Comprehensively, emulsifier-free nanodispersions were sensitive to acidic pH, NaCl and CaCl2 addition. ML and SC coated nanoparticles were sensitive to Ca2+ ions, while T80 stabilized nanodispersions resisted to all environmental stresses, resulting in optimal simulated intestinal absorption.


Assuntos
Emulsificantes , Fenilpropionatos , Emulsões , Tamanho da Partícula , Solventes
9.
J Dermatol Sci ; 103(1): 33-40, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34158211

RESUMO

BACKGROUND: Hair follicle undergoes a growth cycle under the regulation of dermal papilla cells. Due to their enormous roles, these fibroblast cells have been used in various in vitro studies as a screening model to evaluate the effect of hair growth regulating agents. OBJECTIVE: In the current study, we aim to check the hair growth potential effect of Argan press cake (APC) extracted using 50 or 80 % aqueous ethanol on human hair follicle dermal papilla cells (HFDPCs) and to determine the molecular mechanism. METHODS: APC were applied to HFDPCs, then cell proliferation assays, mitochondrial biogenesis assay, and oxidative stress assay were assessed. DNA microarray was performed from the cells treated with our samples and minoxidil. Validation of the results was done using Quantitative Real-Time PCR with primers for hair-growth related genes. GC/MS analysis was used to determine the compounds contained in APC 50 and 80 %. RESULTS: APC enhanced cell proliferation along with the stimulation of the ATP content. Additionally, APC had an anti-oxidant activity against H2O2 mediated oxidative stress preventing dermal papilla cell senescence. Consistent with this, global gene profiling analysis showed an activation of hair growth-related pathway, and a downregulation of inflammation- and oxidative stress-related genes by APC extracts. GC/MS analysis revealed that these extracts contained pure fatty acids, derived sugar chains, and pure compounds including tocopherols, squalene, and spinasterol. CONCLUSION: Taken together, here we showed that APC extracts had an effect on stimulating hair growth while inhibiting the inflammation and the oxidative stress of HFDPCs and thus can potentially contribute to an anti-hair loss drug development.


Assuntos
Alopecia/tratamento farmacológico , Folículo Piloso/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sapotaceae/química , Alopecia/imunologia , Antioxidantes , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Folículo Piloso/imunologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Extratos Vegetais/uso terapêutico
10.
Food Chem ; 337: 127949, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919267

RESUMO

This study compared the interfacial and emulsifying properties of purified saponins and non-purified saponin-rich extracts of Glycyrrhiza glabra, and highlighted potential mechanisms by which crude surface-active compositions, such as liquorice root extract (LRE), act as emulsifiers. LRE presented different fluid properties, in comparison to purified glycyrrhizin (PG), at equivalent glycyrrhizin concentrations. Particularly, it exhibited limited glycyrrhizin fibrilization at pH < pKa and efficiently reduced the interfacial tension at the soybean oil/water interface, independently of pH. LRE also presented better emulsification properties, in comparison to PG samples. Emulsions prepared using LRE had lower droplet sizes when using higher oil mass fractions or lower homogenization pressures, which was attributed to 2 main factors: (i) efficient adsorption of glycyrrhizin molecules at relatively low interfacial curvatures, thus accelerating oil phase breakup during homogenization and (ii) sufficient coverage of newly generated droplets due to adsorption of residual surface-active components (e.g. proteins), thus minimizing droplet coalescence.


Assuntos
Emulsificantes/química , Ácido Glicirrízico/química , Extratos Vegetais/química , Emulsões/química , Glycyrrhiza/química , Saponinas/química , Óleo de Soja/química , Tensão Superficial , Água/química
11.
Carbohydr Polym ; 251: 116990, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142562

RESUMO

Microfibrillated cellulose (MFC) from Argan (Argania spinosa) shells was prepared by chemical purification of cellulose, then mechanical disintegration via high pressure homogenization was performed to isolate fibrils of cellulose. Chemical characterization of raw argan shell (AS-R), purified cellulose (AS-C), and argan shell MFC (AS-MFC) included FT-IR, XRD and NMR. Morphological characterization of AS-MFC was assessed using TEM. Next, the use of AS-MFC as oil-in-water (O/W) emulsions stabilizer was investigated. The particle concentration was observed to affect the long-term stability of the emulsions; high concentrations (0.5-1 % w/w) of AS-MFC resulted in emulsions that were thermodynamically stable during 15 days of storage, which was demonstrated by the droplet's size evolution. The suitable oil concentration for a maximum volume of emulsion using 1 % w/w AS-MFC was demonstrated. The results show that AS-MFC is able to stabilize 70 % w/w MCT oil without visual phase separation. Finally, CLSM shows the adsorption of AS-MFC at the oil-water interface and the formation of a 3D network surrounding oil droplets, confirming Pickering emulsion formation and stabilization.


Assuntos
Celulose/química , Sapotaceae/química , Eletrólitos , Emulsões , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Nanofibras/química , Nanofibras/ultraestrutura , Tamanho da Partícula , Óleos de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Difração de Raios X
12.
Food Chem ; 261: 322-328, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29739600

RESUMO

The formulation, physicochemical stability and bioaccessibility of astaxanthin (AST) loaded oil-in-water nanoemulsions fabricated using gypenosides (GPs) as natural emulsifiers was investigated and compared with a synthetic emulsifier (Tween 20) that is commonly applied in food industry. GPs were capable of producing nanoemulsions with a small volume mean diameter (d4,3 = 125 ±â€¯2 nm), which was similar to those prepared using Tween 20 (d4,3 = 145 ±â€¯6 nm) under the same high-pressure homogenization conditions. GPs-stabilized nanoemulsions were stable against droplet growth over a range of pH (6-8) and thermal treatments (60-120 °C). Conversely, instability occurred under acidic (pH 3-5) and high ionic strength (25-100 mM CaCl2) conditions. In comparison with Tween 20, GPs were more effective at inhibiting AST from degradation during 30 days of storage at both 5 and 25 °C. However, GPs led to lower lipid digestion and AST bioaccessibility from nanoemulsions than did Tween 20.


Assuntos
Emulsificantes/química , Emulsões/química , Gynostemma/química , Cinética , Concentração Osmolar , Extratos Vegetais/química , Polissorbatos/química , Xantofilas/química
13.
Food Res Int ; 106: 542-548, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579959

RESUMO

Açaí berry is the fruit of an Amazonian palm tree and rich in anthocyanins (ACNs). Scientific studies have proven the health benefits of açaí berry and declared this fruit as "super fruit". ACNs have high antioxidant activities, but they are unstable and can easily deteriorate during food processing. In order to protect ACNs and increase their applicability, food-grade water-in-oil (W/O) emulsions were successfully formulated with different concentrations of açaí berry extracts (AEs). The formulated W/O nanoemulsions were relatively stable, with no phase separation after 30 days of storage. The average droplet size varied between 146.8 and 814.8 nm, with higher values corresponding to samples without AEs. All W/O nanoemulsion samples exhibited antioxidant activity and high retention rates of polyphenols after 30 days of storage. ACN retention followed first-order kinetics, with high protection of ACNs observed in emulsified samples. 2% AE encapsulated in a 30 wt% W/O nanoemulsion had an estimated half-life of 385 days. The results indicate that stable nanoemulsion systems with high ACN protection can be produced with possible applications in the food and pharmaceutical industries.


Assuntos
Antocianinas/química , Antioxidantes/química , Euterpe/química , Manipulação de Alimentos/métodos , Frutas/química , Nanopartículas , Óleos/química , Água/química , Antocianinas/isolamento & purificação , Antioxidantes/isolamento & purificação , Emulsões , Armazenamento de Alimentos , Meia-Vida , Cinética , Nanotecnologia , Tamanho da Partícula
14.
Food Chem ; 246: 457-463, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29291873

RESUMO

In this study, we formulated and stabilized oil-in-water nanoemulsions using a crude extract from argan press-cake as sole emulsifier. Various extracts from argan press-cake were prepared in order to select the most surface-active one(s) foreseeing emulsions preparation. Fifty percent (v/v) ethanolic extract reduced the interfacial tension to a minimum value at both MCT oil and soybean oil interfaces (12.7 and 10.5 mN m-1 respectively). This extract was also effective at producing fine emulsions with small droplet sizes (d3,2 < 115 nm) and good physical stability using different oils such as soybean oil, MCT oil and fish oil and at conventional homogenization conditions (100 MPa for 4 passes). On the other hand, the emulsions were very sensitive to NaCl addition (≥25 mM) and to acidic pH (<3) indicating that the main stabilization mechanism is electrostatic, likely due to the presence of surface-active compounds with ionizable groups such as saponins.


Assuntos
Emulsões/química , Óleos de Plantas/química , Emulsificantes/química , Óleos de Peixe/química , Nanoestruturas/química , Saponinas/química , Cloreto de Sódio/química , Óleo de Soja/química , Tensão Superficial , Água/química
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