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1.
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
2.
Rev. Bras. Saúde Mater. Infant. (Online) ; 22(4): 863-870, Oct.-Dec. 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1422688

RESUMO

Abstract Objectives: microbiological quality of raw human milk (HM) from donors at the HMB (Human Milk Bank) of Santa Casa de Misericórdia de Ouro Preto was evaluated. Methods: the microbiological quality of milk from each of 10 donors in triplicate (30 samples) was evaluated by enumeration of Staphylococcus aureus and total aerobic mesophiles (surface plating) and total and thermotolerant coliforms (Most Probable Number - MPN). A questionnaire and a checklist were applied after the end of sample collection to verify the compliance of milk extraction and storage procedures by the donors. Results: inadequacies in the procedures for expression and storage of donated HM were observed. The presence of all microorganisms studied were verified in the milk of all donors, and in some cases exceeded the safety limits. The checklist indicated that some necessary hygienic-sanitary procedures were not carefully performed, making it important to properly guide the donors. Conclusions: this study points to an unfavorable scenario for the safety and quality of donated HM, and it is important to encourage further studies to be conducted so that the Brazilian network of HMB adopts stricter criteria for instructions on procedures and support for HM donors.


Resumo Objetivos: avaliou-se a qualidade microbiológica do leite humano (LH) cru de doadoras do Banco de Leite Humano (BLH) da Santa Casa de Misericórdia de Ouro Preto. Métodos: a qualidade microbiológica do leite de cada uma das 10 doadoras em triplicata (30 amostras) foi avaliada por meio da enumeração de Staphylococcus aureus e mesóflos aeróbios totais (plaqueamento em superfície) e coliformes totais e termotolerantes (Número Mais Provável -NMP). Para verificar a conformidade dos procedimentos de extração e armazenamento do leite pelas doadoras, aplicou-se um questionário e um checklist após o término da coleta das amostras. Resultados: observou-se inadequações nos procedimentos de expressão e armazenamento do LH doado. A presença de todos os microrganismos estudados foram verificados no leite de todas as doadoras e, em alguns casos, excedeu os limites de segurança. O checklist indicou que alguns procedimentos higiênico-sanitários necessários não foram realizados criteriosamente, tornando importante orientar adequadamente as doadoras. Conclusões: este estudo aponta um cenário desfavorável para a segurança e a qualidade do LH doado, sendo importante incentivar mais estudos a serem realizados para que a rede brasileira de BLH adote critérios mais rigorosos de instruções sobre procedimentos e suporte para doadoras de LH.


Assuntos
Humanos , Feminino , Gravidez , Controle de Qualidade , Qualidade dos Alimentos , Bancos de Leite Humano/normas , Extração de Leite/métodos , Microbiologia de Alimentos , Leite Humano/microbiologia , Brasil
3.
Crit Rev Anal Chem ; : 1-27, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35993795

RESUMO

Citrus fruits (CF) are highly consumed worldwide, fresh, processed, or prepared as juices and pies. To illustrate the high economic importance of CF, the global production of these commodities in 2021 was around 98 million tons. CF's composition is considered an excellent source of phenolic compounds (PC) as they have a large amount and variety. Since ancient times, PC has been highlighted to promote several benefits related to oxidative stress disorders, such as chronic diseases and cancer. Recent studies suggest that consuming citrus fruits can prevent some of these diseases. However, due to the complexity of citrus matrices, extracting compounds of interest from these types of samples, and identifying and quantifying them effectively, is not a simple task. In this context, several extractive and analytical proposals have been used. This review discusses current research involving CF, focusing mainly on PC extraction and analysis methods, regarding advantages and disadvantages from the perspective of Green Chemistry.

4.
Food Res Int ; 157: 111252, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761564

RESUMO

This work aimed to develop an integrated method to extract and fractionate phenolic compounds from lemon (Citrus limon L.) peel by in-line coupling pressurized liquid extraction and solid-phase extraction (PLE-SPE). The effect of the adsorbent used in the SPE (Sepra™ C18-E, Sepra™ NH2, and PoraPak Rxn), the combination of organic extraction-elution solvents (water-ethanol and water-ethyl lactate), extraction temperature (40-80 °C), and extraction water pH (4.0, 6.0, and 7.0) were the investigated variables. The highest yield and separation degree were observed using Sepra™ C18-E and the water-ethanol combination as the extraction solvent-eluent. Higher temperatures led to higher yields but negatively affected the retention of less polar compounds, hesperidin, and narirutin during the extraction step. The lower pH improved the yield of most evaluated compounds; however, it did not improve the adsorbent retention at high temperatures. Thus, the developed PLE-SPE method resulted in higher extraction yields from lemon peel, especially total less polar compounds (20.2100 ± 0,0050 mg/g) and hesperidin (12.8120 ± 0.0006 mg/g) and allowed the separation of polar compounds and less polar compounds in distinct extract fractions. Besides, PLE-SPE resulted in higher yields compared to other extraction methods. The integrated approach allowed obtaining extract fractions with different chemical composition through an environmentally friendly procedure. The research outcomes may be helpful for natural products chemistry, and industrial processes.


Assuntos
Citrus , Hesperidina , Etanol , Fenóis/química , Extração em Fase Sólida , Solventes/química , Água
5.
Food Chem X ; 12: 100133, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34632369

RESUMO

Apple is one of the most consumed fruits worldwide and has recognized nutritional properties. Besides being consumed fresh, it is the raw material for several food products, whose production chain generates a considerable amount of by-products that currently have an underestimated use. These by-products are a rich source of chemical compounds with several potential applications. Therefore, new ambitious platforms focused on reusing are needed, targeting a process chain that achieves well-defined products and mitigates waste generation. This review covers an essential part of the apple by-products reuse chain. The apple composition regarding phenolic compounds subclasses is addressed and related to biological activities. The extraction processes to recover apple biocompounds have been revised, and an up-to-date overview of the scientific literature on conventional and emerging extraction techniques adopted over the past decade is reported. Finally, gaps and future trends related to the management of apple by-products are critically presented.

6.
Anal Chim Acta ; 1178: 338845, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482871

RESUMO

The comprehensive analysis of phenolic compounds from natural products comprises critical steps, including quantitative extraction, extract preparation, and chromatographic procedure. Performing these steps off-line requires a long time to obtain results, besides being laborious and more error-prone. This work discusses the concept and presents the details of assembling and validating a new system to comprehensively analyze phenolic compounds in natural products. The system is based on a bidimensional separation through the combination of pressurized liquid extraction with in-line solid-phase extraction coupled online with HPLC-PDA. The system proved to be able to perform a bidimensional separation to characterize the sample and ensure quantitative extraction of all detected components using the most appropriate extraction solvent gradient depending on the raw sample analyzed. The 1st dimension separation is achieved by PLE-SPE with a solvent gradient and differential interactions of extracted compounds with the adsorbent. The 2nd dimension presents the HPLC-PDA separation. The extraction/separation process can be monitored in real-time, and kinetic extraction curves for individual compounds can also be obtained to ensure quantitative extraction. Thus, the 2D PLE-SPE × HPLC-PDA may provide fast and precise comprehensive analyses of a large plethora of phenolic compounds, finding relevant applications in the chemical, food, pharmaceutical, and agricultural fields.


Assuntos
Produtos Biológicos , Cromatografia Líquida de Alta Pressão , Fenóis/análise , Extração em Fase Sólida , Solventes
7.
Food Chem (Oxf) ; 2: 100008, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35415638

RESUMO

The in-line coupling of the pressurized liquid extraction with a solid-phase adsorbent and a UV-Vis detector for the simultaneous extraction and separation of bioactive compounds from yerba mate (PLE-SPE-UV) was carried out in two stages. In the first stage, water was used as a solvent, while in the second stage, ethanol was used. For the optimization of the method, different adsorbents (Sepra C18-E, Isolute C18-EC, and Strata-X C18), temperatures (40-80 °C), solvent flow-rate (1-3 mL/min), and pH (4.0 and 8.0) were evaluated. By using a UV-Vis detector on-line, it is possible to monitor the process in real-time. The developed method allowed obtaining similar or higher recoveries of all the compounds classes than other methods, such as ultrasound-assisted extraction, stirring, maceration, and pressurized liquid extraction alone, in addition to separating them into fractions. The developed method could be used as sample preparation for the analysis of different compounds classes from mate.

8.
Front Chem ; 8: 507887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33102442

RESUMO

Flavonoids are one of the main groups of polyphenols found in natural products. Traditional flavonoid extraction techniques are being replaced by advanced techniques to reduce energy and solvent consumption, increase efficiency and selectivity, to meet increased market demand and environmental regulations. Advanced technologies, such as microwaves, ultrasound, pressurized liquids, supercritical fluids, and electric fields, are alternatives currently being used. These modern techniques are generally faster, more environmentally friendly, and with higher automation levels compared to conventional extraction techniques. This review will discuss the different methods available for flavonoid extraction from natural sources and the main parameters involved (temperature, solvent, sample quantity, extraction time, among others). Recent trends and their industrial importance are also discussed in detail, providing insight into their potential. Thus, this paper seeks to review the innovations of compound extraction techniques, presenting in each of them their advantages and disadvantages, trying to offer a broader scope in the understanding of flavonoid extraction from different plant matrices.

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