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1.
Food Chem ; 388: 132902, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35447579

RESUMO

The internal breakdown (IB) is a premature and uneven mango pulp ripening physiological disorder that is noticed only when the fruit is sliced for consumption. Thus, there is a demand for analytical methods to detect IB in mangoes to avoid consumer dissatisfaction and reduce postharvest waste. In this work, physicochemical and volatile compounds were determined to evaluate the ability to predict pulp IB. Principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) of the data show that color, firmness, and volatiles compounds are important to give some information about the physiological changes caused by IB. The volatile compounds methacrylic acid, ethyl ester, isopentyl ethanoate, limonene oxide, (E)-2-pentenal, tetradecane, and γ-elemene were identified as chemical markers of IB. Therefore, mango physical and chemical characteristics combined with PCA and PLS-DA were successfully employed for the identification of IB in mangoes, showing significant differences between healthy and IB fruits.


Assuntos
Mangifera , Análise Discriminante , Frutas/química , Análise dos Mínimos Quadrados , Mangifera/química , Análise de Componente Principal
2.
Food Chem ; 369: 130753, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488135

RESUMO

Approximately 11.4 million tonnes of solid by-products and an increased amount of waste water will be generated during the 2020/21 coffee harvest. There are currently no truly value-adding uses for these potentially environmentally threatening species. This work presents the most wide-ranging chemical investigation of coffee by-products collected from farms to factories, including eight never previously investigated. Twenty compounds were found for the first time in coffee by-products including the bioactive neomangiferin, kaempferol-3-O-rutinoside, lup-20(29)-en-3-one and 3,4-dimethoxy cinnamic acid. Five by-products generated inside a factory showed caffeine (53.0-17.0 mg.g-1) and/or chlorogenic acid (72.9-10.1 mg.g-1) content comparable to coffee beans, while mature leaf from plant pruning presented not only high contents of both compounds (16.4 and 38.9 mg.g-1, respectively), but also of mangiferin (19.4 mg.g-1) besides a variety of flavonoids. Such by-products are a source of a range of bioactive compounds and could be explored with potential economic and certainly environmental benefits.


Assuntos
Café , Extratos Vegetais , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Fazendas
3.
Food Chem ; 373(Pt B): 131323, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34782213

RESUMO

The main precursors of bitter principles of beer are α-acids, followed by ß-acids. Determination of their content in hop cones and their derivatives is an essential part of brewing. HPLC-UV is the preferred technique when a more precise quantification of some specific bitter acids are required. However, current methods do not allow the proper quantification of all the six major α- and ß-acids; furthermore, these multi-step methods generate considerable volumes of chemical waste. In this work, a new UHPLC-UV protocol was developed and compared side-by-side with reference, considering traditional and sustainability parameters. Baseline separations were achieved for the six major bitter acids and xanthohumol, while a greener and faster sample preparation procedure was developed. The new validated procedure could be adopted for quality control of hops and their derivative products with enhanced sample throughput and with a potential gain in the safety of the analyst.


Assuntos
Humulus , Propiofenonas , Cerveja/análise , Flavonoides/análise
4.
Molecules ; 24(20)2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31652589

RESUMO

Chemometrics is the chemistry field responsible for planning and extracting the maximum of information of experiments from chemical data using mathematical tools (linear algebra, statistics, and so on). Active pharmaceutical ingredients (APIs) can form impurities when exposed to excipients or environmental variables such as light, high temperatures, acidic or basic conditions, humidity, and oxidative environment. By considering that these impurities can affect the safety and efficacy of the drug product, it is necessary to know how these impurities are yielded and to establish the pathway of their formation. In this context, forced degradation studies of pharmaceutical drugs have been used for the characterization of physicochemical stability of APIs. These studies are also essential in the validation of analytical methodologies, in order to prove the selectivity of methods for the API and its impurities and to create strategies to avoid the formation of degradation products. This review aims to demonstrate how forced degradation studies have been actually performed and the applications of chemometric tools in related studies. Some papers are going to be discussed to exemplify the chemometric applications in forced degradation studies.


Assuntos
Química Farmacêutica/métodos , Preparações Farmacêuticas/química , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Estabilidade de Medicamentos , Excipientes , Temperatura Alta , Umidade , Análise dos Mínimos Quadrados , Redes Neurais de Computação , Oxirredução , Análise de Componente Principal
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