HPLC/PDA–ESI/MS Identification of Phenolic Acids, Flavonol Glycosides and Antioxidant Potential in Blueberry, Blackberry, Raspberries and Cranberries

Kim

et al. 2018

Eur Food Res Technol

Most previous studies have been focused on the variation of tea chemical composition by fermentative processes as well as different cultivars and regions. The detailed changes of flavonoid profiles were described for the first time by each processing step of green and black tea leaves in this study. A total of 24 flavonoid derivatives including catechins, theaflavins, and flavonols were separated and identified from the tea samples based on UPLC-DAD-QToF/MS data and constructed library. Among these, the fragmentation pathway of theaflavins was proposed specifically in positive ionization mode for structural interpretation. During leaf processing, the individual flavonols were changed as diverse patterns according to their aglycone types and glycosylated forms, but their total content showed a slight difference. EGCG and ECG were increased after roasting approximately twofold higher than that of fresh leaves (EGCG, 2709.5 →6085.6; ECG, 1548.0 →2318.2 mg/100 g dry weight, respectively) in green tea while considerably decreased their contents due to oxidation and conversion to theaflavins after fermentation during black tea processing. Especially, the drying steps also found to be factor to influence positively to increase the flavonoid contents in both tea processing. Therefore, this result indicated that detailed conditions of each processing step played important roles in changing the flavonoid profiles from tea leaves.

Section: Identification Of Catechins Theaflavins and Flavonols In Gmentioning

confidence: 88%

Characterization of catechins, theaflavins, and flavonols by leaf processing step in green and black teas (Camellia sinensis) using UPLC-DAD-QToF/MS

Kim

et al. 2018

Eur Food Res Technol

Phenolic Compounds - Natural Sources, Importance and Applications

“…In the last years, this new method has been strongly implemented in academies in basic research, pharmaceutical and agro-chemical industries to study physical, chemical and biological properties of a great diversity of compounds, as well, and quality control of drugs, foods and natural products. In Table 4 are presented some recent works [139][140][141][142][143][144][145] in which HPLC-MS was efectively used for polyphenol characterization of plants and food with very accurate results.…”

Section: The Use Of Hplc-dad/uv-vis and Hplc-msmentioning

confidence: 99%

Phenolics in Foods: Extraction, Analysis and Measurements

Aires¹

2017

The increasing consumers demands to acquire healthier fruits and vegetables as well as the urgency in looking to natural compounds with antioxidant activity and enhanced antimicrobial activity against antibiotic-resistant pathogenic bacterial strains have encouraged a quick expansion of research studies about enhanced phenolic extraction and identiication methods. Considering the importance of phenolics as natural compounds with antioxidant and antimicrobial activity, this chapter aims to present the most updated information about extraction methods, ranging from the traditional to the most advanced processes, as well as the access to the modern methods used in the identiication and quantiication of phenolics. The main goal of this chapter is to provide the reader with a broad view on the diferent protocols used to extract, identify and quantify phenolic compounds from diferent kinds of foods, including fruits and vegetables.Keywords: phytochemicals, extraction, determination, colorimetric methods, HPLC, HPLC-MS IntroductionThe growing resistance of pathogenic bacterial isolates against the traditional chemical antibiotics as well as the resurgent of old disappeared diseases associated with the constant consumers' demanding of healthier, nutritious and safe food has led the researchers to focus on searching for new, safe and efective molecules. One class of such molecules is the class of polyphenols. Polyphenols are a ubiquitous class of compounds largely present in plants as their secondary metabolites, which are synthesized during their normal development [1] in response to several stressful biotic and abiotic factors [2,3]. This class of compounds are a much diversiied group derived from the amino acids phenylalanine and tyrosine and The results from the last decade's research have shown that polyphenols have important beneicial properties for human health, including antioxidative, antiaging, antibacterial and antimutagenic [7][8][9][10][11]. Moreover, the recent evidence of their interaction with proteins, DNA and other biological molecules has enhanced their exploitation for the production of new natural product-derived therapeutic agents. Despite these advantages, several limitations still persist, particularly those related with their extraction eiciency, which afects the large-scale use of some of these substances. The diiculties in screening, extracting, separation and purifying these compounds have increased the development of new and modern methods to address these limitations. In this context, the aim of this chapter is to present an updated review about sources, technologies and methods that have been developed until now to improve the extraction, detection, separation and full characterization of such beneicial compounds, with special emphasis to their possible application in the design of nutraceuticals and functional food products. Foods as natural resources of phenolicsPolyphenols have been exhaustively studied in their diferent natural matrices such as fruits, vegetables, teas, algae a...

“…It has nonetheless been demonstrated that these compounds may block free radicals and are capable of preventing reactions caused by the single active atoms of oxygen. Phenolic compounds act as antioxidants, and their activity is defined in line with their chemical structure (Zoriţa, Florica, Rugină, Lucian, & Socaciu, 2014). Storage of raspberries in atmospheres containing ozone in concentration ranging from 0.3 to 0.9 mg/L in time ranging from 60 to 120 min contributed to a statistically significant (p < 0.05) change of phenolic compound content as compared to the control batch untreated with ozone.…”

Section: Chemical Quality Parameters Titratable Acidity (%)mentioning

confidence: 99%

The impact of ozone on health-promoting, microbiological, and colour properties ofRubus ideausraspberries

Onopiuk

Półtorak

Moczkowska

et al. 2017

CyTA - Journal of Food

The purpose of the study was to define the impact of ozonisation duration and concentration on selected chemical, physical, and microbiological properties of Rubus ideaus red-fruited raspberries of the Polka variety. Raspberry fruit was exposed to a stream of ozone in concentration of 0.3 and 0.9 mg/L over a period of 60 and 120 min. The scope of the study covered the measurements of titratable acidity, soluble solids concentration, and such health-promoting indicators as content of phenol compounds, flavonoids, anthocyanins and vitamins C, total antioxidant activity (TAA) on 0, 4th, and 8th day of storage. The ozone treated fruit had higher level of phenol compounds and demonstrated higher TAA compared to untreated raspberries. The use of ozone made it possible to curb the development of yeast and moulds on the surface of raspberries, in which the dosage of 0.9 mg/L and treatment time of 60 min proved most efficient.Impacto del ozono en las propiedades promotoras de la salud, microbiológicas y de color de la frambuesa Rubus ideaus RESUMEN El presente estudio se propuso definir el impacto que la duración y la concentración de la ozonización tienen sobre determinadas propiedades químicas, físicas y microbiológicas de frambuesas rojas, Rubus ideaus, de la variedad polka. Con este objetivo, la fruta de la frambuesa fue expuesta a un chorro de ozono en concentraciones de 0,3 y 0,9 mg/L durante 60 y 120 minutos. El alcance del estudio permitió medir la acidez valorable, la concentración de sólidos solubles y los indicadores de las propiedades promotoras de la salud, que incluyen el contenido de compuestos fenólicos, flavonoides, antocianinas y vitamina C, así como el total de actividad antioxidante en los días 0, 4 y 8 de almacenamiento. La fruta sometida al tratamiento con ozono presentó niveles más elevados de compuestos fenólicos y de actividad antioxidante en comparación con los mostrados por las frambuesas no tratadas. Además, el uso de ozono ayudó a limitar el crecimiento de levadura y moho en la superficie de las frambuesas, constatándose que el tratamiento con una dosis de ozono de 0.9 mg/L durante 60 minutos fue el más eficiente. ARTICLE HISTORY