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1.
Ultrason Sonochem ; 107: 106906, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776867

RESUMO

The interest in natural colorants derived from sustainable processes has prompted research into obtaining bixin from defatted annatto (Bixa orellana L.) seeds. Bixin is a compound that imparts yellow-orange-red coloration, known for its high biodegradability, low toxicity, and wide industrial applicability. Meanwhile, high-intensity ultrasound (HIUS) technology has emerged as a promising method for extracting natural colorants, offering higher yields through shorter processes and minimizing thermal degradation. Although some studies have demonstrated the efficiency of HIUS technology in bixin extraction, research on the effects of acoustic cavitation on the properties of the colorant remains limited. Therefore, this study aimed to investigate the influence of HIUS-specific energy levels (0.02, 0.04, 0.12, and 0.20 kJ/g) on the chemical, physical, and morphological characteristics of annatto extracts containing bixin and geranylgeraniol. Single-step extractions of bixin using ethanol as a solvent were evaluated at various acoustic powers (4.6, 8.5, 14.5, and 20 W) and extraction times (0.5, 1, 3, and 5 min) to determine their impact on the yield of natural colorant extraction. Increasing the acoustic power from 4.6 to 20 W and extending the extraction time from 0.5 to 5 min resulted in higher yields of natural colorant, likely due to the effects of acoustic cavitation and increased heat under more intense conditions. However, elevated levels of mechanical and thermal energy did not affect the chemical properties of the colorant, as indicated by UV-Vis and FTIR spectra. Conversely, higher specific energies yielded colorants with a more intense red hue, consistent with increased bixin content, and altered the microstructure and physical state, as observed in X-ray diffractograms. Nevertheless, these alterations did not impact the solubility of the colorant. Therefore, employing a cleaner extraction procedure aided by one-step ultrasound facilitated the recovery of natural colorants and contributed to the biorefining of annatto seeds, enabling the production of a rich geranylgeraniol colorant through a sustainable approach.


Assuntos
Bixaceae , Carotenoides , Sementes , Ondas Ultrassônicas , Sementes/química , Bixaceae/química , Carotenoides/química , Carotenoides/isolamento & purificação , Fracionamento Químico/métodos , Diterpenos/química , Diterpenos/isolamento & purificação , Cor , Extratos Vegetais
2.
Int J Biol Macromol ; 270(Pt 1): 132307, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38740151

RESUMO

Chitosan, derived from the abundant biopolymer chitin, has emerged as a promising option for water treatment due to its intrinsic bioavailability. This review emphasizes the notable characteristics of chitosan, which allow for various modifications, expanding its applications. The polymer's effectiveness in adsorbing contaminants, particularly in advanced water treatment technologies, is highlighted. The review underscores the potential of chitosan-based hybrid materials, including nanocomposites, hydrogels, membranes, films, sponges, nanoparticles, microspheres, and flakes, as innovative alternatives to traditional chemical-based adsorbents. The advantages of using these materials in wastewater treatment, especially in removing heavy metals, dyes, and emerging compounds, are explored. The study delves into the mechanisms involved in wastewater treatment with chitosan, emphasizing the interactions between the polymer and various contaminants. Additionally, the application of chitosan as a contaminant removal agent in a post-pandemic context is addressed, considering the challenges related to waste management and environmental preservation. The analysis highlights the potential contribution of chitosan in mitigating environmental impacts post-pandemic, offering practical solutions for treating contaminated effluents and promoting sustainability. The study addresses current obstacles and prospects for chitosan-based wastewater treatment, emphasizing its promising role in sustainable water management.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Purificação da Água/métodos , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Águas Residuárias/química , Metais Pesados/química
3.
Food Res Int ; 182: 114134, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519156

RESUMO

Hesperidin is a phenolic compound usually found in citrus fruits, which is known for its anti-inflammatory and antioxidant properties. This bioactive compound has already been used to formulate medications to treat chronic venous insufficiency. In this work, through a system which allows the in-line coupling of the pressurized liquid extraction (PLE) and high-intensity ultrasound (HIUS) with solid phase extraction (SPE), and analysis by high-performance liquid chromatography with UV-Vis detector (HPLC-UV) in on-line mode, a method was developed to obtain, separate, and quantify hesperidin from the industrial waste of lime. An eco-friendly approach with water and ethanol as extraction solvents was used. Parameters such as temperature (80, 100, and 120 °C) and HIUS power (0, 200, and 400 W) were evaluated regarding hesperidin yield. In this context, the higher hesperidin yield (18.25 ± 1.52 mg/g) was achieved using water at a subcritical state (120 °C and 15 MPa). The adsorbent SepraTM C-18-E isolated hesperidin from the other extracted compounds employing 50% ethanol in the SPE elution. The possibility ofon-lineanalysis coupling a high-performance liquid chromatograph to an ultraviolet detector (HPLC-UV) system was studied and shown to be a feasible approach for developing integrated technologies. Conventional extractions and their antioxidant capacities were evaluated, highlighting the advantages of the HIUS-PLE-SPE extractive method. Furthermore, the on-linechromatographic analysis showed the potential of the HIUS-PLE-SPE- HPLC-UV system to quantify the extracted compounds in real time.


Assuntos
Compostos de Cálcio , Hesperidina , Óxidos , Antioxidantes , Água/química , Etanol
4.
Food Res Int ; 175: 113690, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129032

RESUMO

This study proposed an integrated and automated procedure to extract, separate, and quantify bioactive compounds from a coffee co-product by pressurized liquid extraction (PLE) coupled inline with solid phase extraction (SPE) and online with HPLC-PDA (PLE-SPE × HPLC-PDA). The efficiency of the two-dimensional system in performing real-time analysis was verified by comparing HPLC-PDA results acquired by the system (online) and carried out after the extract fraction collection (offline). Different flow rates (1.5 mL/min for 336 min, 2 mL/min for 246.4 min, and 2.5 mL/min for 201.6 min) were evaluated to optimize the extraction, separation, and analysis method by PLE-SPE × HPLC-PDA. Subcritical water at 125 °C and 15 min of static time allowed the highest extraction yields of caffeine and 5-caffeoylquinic acid (5-CQA). Caffeine was retained during the aqueous extraction in the SPE adsorbent and eluted from the column by exchanging the solvent for a hydroethanolic mixture. Thus, caffeine was separated from 5-CQA and other phenolic compounds, producing extracts with different compositions. The solvent flow rate did not have a significant effect (p-value ≥ 0.05) on the extraction, separation, and analysis (by online and offline methods) of 5-CQA. However, the online quantification of retained compounds in the SPE (i.e., caffeine) can underestimate concentration compared to offline analysis. Nevertheless, the results suggest that coupling of advanced techniques can be used to efficiently extract, separate, and analyze fractions of phenolic compounds, supplying an integrated method to produce high-added value ingredients for several applications.


Assuntos
Cafeína , Café , Cromatografia Líquida de Alta Pressão/métodos , Cafeína/análise , Fenóis/análise , Extração em Fase Sólida/métodos , Solventes/análise
5.
Anal Chim Acta ; 1272: 341494, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355330

RESUMO

Analyzing compounds such as polyphenols in solid samples frequently uses a solid-liquid extraction step. The solid-liquid extraction and analysis integration in a single equipment is not commercially available since several challenges are inherent to this hybridization. In the context of developing more sustainable analytical procedures, innovative techniques are demanded. Given that, this work proposes a new integrative system (2D PLE × HPLC-PDA) and presents its validation for bioactive compound extraction and online quantification, discussing the main advantages and cares that need to be taken. Two food byproducts - passion fruit bagasse and coffee husks - were chosen as solid model samples. The system was configured to perform pressurized liquid extraction (PLE) with periodical automated extract injection in the HPLC, consequently obtaining the online quantification of target compounds from the solid samples. In parallel with the online injections, extract fractions were collected and submitted to offline analysis in which the extraction yield of piceatannol and chlorogenic acid and caffeine were evaluated, respectively, for passion fruit bagasse and coffee husks. The extraction yields obtained by online and offline injections were compared and were significantly equal (p > 0.05). Thus, the 2D PLE × HPLC-PDA system represents a feasible tool to integrate solid sample preparation and chemical analysis of biocompounds in a single and online step.


Assuntos
Ácido Clorogênico , Polifenóis , Cromatografia Líquida de Alta Pressão/métodos , Polifenóis/análise , Antioxidantes/química , Extratos Vegetais/química
6.
Carbohydr Polym ; 270: 118374, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34364618

RESUMO

Inulin-type fructans with different degrees of polymerization (DPs) were used as wall materials for the blue colorant produced from the crosslinking between genipin and milk proteins. The impact of using fructooligosaccharides (FOS) with DP = 5 and inulins with DP ≥ 10 (GR-In) and DP ≥ 23 (HP-In) on the physical (microstructure, size, water activity, wettability, solubility, water adsorption, glass transition temperature, and color), chemical (free genipin retention and moisture), and technological (colorant power, pH stability, and thermal stability) properties of the powdered blue colorant was examined. Inulins were more efficient carriers as seen from the physical characteristics of the microparticles. FOS and GR-In promoted higher retention of free genipin than HP-In. Additionally, their lower DP influenced the rehydration proprieties as well as the color intensity and colorant power. The DP did not affect the physical stability of the colorant at different pH conditions or at high temperature. Our findings demonstrated that the DP of the fructan exhibited a strong impact on the blue intensity of the samples and also their rehydration capacity.


Assuntos
Corantes/química , Frutanos/química , Iridoides/química , Proteínas do Leite/química , Fenômenos Químicos , Humanos , Inulina/química , Oligossacarídeos/química , Tamanho da Partícula , Polimerização , Pós/química , Solubilidade , Temperatura , Água , Molhabilidade
7.
Environ Sci Pollut Res Int ; 26(28): 28436-28443, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30793244

RESUMO

The increase in biodiesel production has been leading to an excess amount of crude glycerol and, consequently, serious environmental issues. For this reason, electrospun chitosan-based nanofibers (CB-EN), composed by chitosan and poly(ethylene oxide) (PEO), were synthesized to apply in the biosorption of impurities from industrial glycerol. To evaluate the biosorption efficiency, the chitosan-based nanofiber was compared to other chitosan-based biosorbents (chitosan biopolymeric film and chitosan powder). The equilibrium and thermodynamic studies were successfully performed to comprehend the interaction mechanisms through the biosorption of glycerol pigments onto electrospun chitosan-based nanofibers. The temperature effect was evaluated by experimental equilibrium curves. Freundlich and BET models were used to estimate isotherm parameters. Gibbs free energy change, enthalpy change, entropy change, and isosteric heat of biosorption were quantified. The equilibrium curves showed that the highest equilibrium relative adsorption (340.7 g-1) was reached at 60 °C. The BET model was the most suitable to represent the equilibrium behavior. The thermodynamic parameters indicated that the biosorption was spontaneous, exothermic, random, and energetic heterogeneous. Therefore, this work developed a green and efficient alternative to refine industrial glycerol. Graphical abstract Note: This data is mandatory. Please provide.


Assuntos
Quitosana/química , Glicerol/metabolismo , Nanofibras/química , Adsorção , Biocombustíveis , Glicerol/química , Termodinâmica
8.
RSC Adv ; 10(1): 112-121, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-35492546

RESUMO

In this study, a biorefinery for the processing of turmeric (Curcuma longa L.) based on clean and emerging technologies has been proposed. High-intensity ultrasound (HIUS) technology was evaluated as a promising technique for curcumin recovery aiming to improve its extraction yield and technological properties as a colorant. In addition, we evaluated the effects of process conditions on the turmeric biomass after the extractions. The process variables were the number of stages of extraction with ethanol (1, 3 and 5) and the solvent to feed ratio (S/F) of 3, 5, 7, 9 (w/w). The highest curcumin content (41.6 g/100 g extract) was obtained using 1 wash and a S/F of 5 w/w, while the highest curcumin yield (3.9 g/100 g unflavored turmeric) was obtained using 5 stages and a S/F of 7. The extracts obtained by solid-liquid extraction assisted by HIUS showed a yellow color (157 and 169 of yellowness index) more intense than those obtained by the pressurized liquid extraction technique (101 of yellowness index) and better yield results than low-pressure solid-liquid extraction (using the same processing time). Thus, it was possible to obtain a characteristic yellow colorant with high curcumin yield in a short process time (5 min of extraction) using HIUS technology. Besides that, SEM images and FTIR spectra demonstrated that the turmeric biomasses processed by HIUS technology were not degraded.

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