Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Food Sci Nutr ; 12(1): 255-267, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38268885

RESUMO

Inula helenium roots are consumed as natural flavor components and raw or cooked as food, and their extracts are rich in sesquiterpene lactones such as alantolactone (AL) and isoalantolactone (IAL), which have recently attracted great attention due to their pharmacological properties. The industrial utilization of these compounds requires the development of green, efficient, cost-effective, and sustainable extraction protocols. Therefore, this study focused on the optimization of microwave-assisted extraction (MAE) process variables using Face-Centered Central Composite Design (FC-CCD). Then, maceration was applied as a conventional technique, and these techniques were compared in terms of extraction efficiency, morphological changes, antimicrobial activities, carbon emissions, and energy consumption. As a result, optimal MAE conditions, i.e., EtOH: water ratio (X 1) = 100:0, liquid/sample ratio (X 2) = 30:1 mL/g, microwave power (X 3) = 300 W, and irradiation time (X 4) = 5 min, were obtained with AL and IAL yields of 54.99 ± 0.11 (mg/g) and 48.40 ± 0.19 (mg/g), respectively. The extract obtained by MAE had similar or better activity than positive controls in most cases and formed the largest inhibition zones against E. coli (29.5 ± 0.71 mm) and A. niger (34.75 ± 1.06 mm). Morphological changes of I. helenium roots after extraction were observed by scanning electron microscopy. Additionally, MAE was 43.4 times faster than maceration, resulting in 228.6 times less energy consumption and carbon emissions. Based on these findings, it is recommended to use MAE as an industrial green technique for the extraction of sesquiterpene lactones with potential applications in nutraceuticals and food products in terms of sustainable economy and environmental protection.

2.
J Agric Food Chem ; 63(8): 2305-13, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25647068

RESUMO

Physicochemical, bioactive, and antimicrobial properties of different cold press edible oil byproducts (almond (AOB), walnut (WOB), pomegranate (POB), and grape (GOB)) were investigated. Oil, protein, and crude fiber content of the byproducts were found between 4.82 and 12.57%, between 9.38 and 49.05%, and between 5.87 and 45.83%, respectively. GOB had very high crude fiber content; therefore, it may have potential for use as a new dietary fiber source in the food industry. As GOB, POB, and WOB oils were rich in polyunsaturated fatty acids, AOB was rich in monounsaturated fatty acids. Oil byproducts were also found to be rich in dietary mineral contents, especially potassium, calcium, phosphorus, and magnesium. WOB had highest total phenolic (802 ppm), flavonoid (216 ppm), and total hydrolyzed tannin (2185 ppm) contents among the other byproducts. Volatile compounds of all the byproducts are mainly composed of terpenes in concentration of approximately 95%. Limonene was the dominant volatile compound in all of the byproducts. Almond and pomegranate byproduct extracts showed antibacterial activity depending on their concentration, whereas those of walnut and grape byproducts showed no antibacterial activity against any pathogenic bacteria tested. According to the results of the present study, walnut, almond, pomegranate, and grape seed oil byproducts possess valuable properties that can be taken into consideration for improvement of nutritional and functional properties of many food products.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Lythraceae/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Prunus/química , Vitis/química , Resíduos/análise , Antibacterianos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Manipulação de Alimentos , Nozes/química , Extratos Vegetais/química , Óleos de Plantas/análise , Óleos de Plantas/isolamento & purificação
3.
J AOAC Int ; 96(5): 1158-63, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24282961

RESUMO

This study describes determination of chloramphenicol (CAP) in honey, milk, and egg by LC-electrospray ionization (ESI)-MS. CAP was extracted with ethyl acetate from honey, and with acetonitrile from milk and egg. d5-CAP was used as the internal standard. Separation was achieved on a ZORBAX Eclipse C18 2.1 id, 150 mm, 2.1 pm column. The mass spectrometer was equipped with an ESI interface in negative mode. Mass determination of CAP and d5-CAP was carried out in selected ion monitoring mode by scanning m/z 321 for CAP and m/z 326 for d5-CAP as quantification ions, and m/z 323 as the confirmation ion. The validation of the analytical method was performed by carrying out linearity, LOD, LOQ, accuracy, precision, and recovery. Calibration curve was linear between 0.1 and 20.0 ng/g with correlation coefficient >0.998. Accuracy of the method for the honey sample was 95%, and for the milk powder sample 106%. Precision of the method, expressed as CV%, varied between 1.60 and 4.37 for intraday and 2.00 to 5.67 for interday. Quantification limits of method were 0.05, 0.08, and 0.09 ng/g for egg, milk, and honey, respectively. Recovery of the method ranged between 86 and 103% for all three matrixes and two different concentrations. Finally, the method was checked by participating proficiency tests from the Food Analysis Performance and Assessment Scheme 0281 and 0298 honey samples. Z scores were -1.0 and 0.4, respectively.


Assuntos
Cloranfenicol/análise , Cromatografia Líquida/métodos , Ovos/análise , Mel/análise , Leite/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais
4.
J Agric Food Chem ; 61(31): 7529-36, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23837397

RESUMO

Two types of instant teas produced from low- and high-quality black teas were examined for their proximate composition, dietary fiber, minerals, water-soluble vitamins, total phenolic content, various antioxidant assays, phenolics (flavanols, condensed phenolics, and phenolic acids), alkaloids, and carotenoids as well as taste-active compounds (sugars, organic acids, and free amino acids). Some variations, albeit to different extents, were observed (p < 0.05) among these parameters between instant teas produced from low- and high-quality black teas. With respect to proximate composition, carbohydrate was the predominant component (56.68-59.84 g/100 g), followed by protein (19.31-19.86 g/100 g). Ash, moisture, and, to a lesser extent, dietary fiber and fat were also present in both instant teas. Thirteen minerals, four water-soluble vitamins, six flavanols, two alkaloids, three condensed phenolics, one phenolic acid, and one carotenoid were identified. Total phenolic content varied between 17.35 and 17.82 g of gallic acid equivalents (GAE)/100 g instant tea. With regard to antioxidant activities, three different assays such as oxygen radical absorbance capacity (ORAC), trolox equivalent antioxidant capacity (TEAC), and cupric ion reducing antioxidant capacity (CUPRAC) were measured. No significant differences (p > 0.05) in total phenolic, ORAC, TEAC, and CUPRAC contents between low- and high-quality instant teas were observed. With regard to taste-active compounds, 3 sugars, 5 organic acids, and 18 free amino acids were positively identified, of which fructose, tannic acid, and theanine predominated, respectively. The present work suggests that despite some differences, instant teas produced from low- and high-quality black teas should not be distinguished on the basis of their compositional, nutritional, and functional characteristics as well as taste-active compounds.


Assuntos
Camellia sinensis/química , Extratos Vegetais/análise , Chá/química , Antioxidantes/análise , Fibras na Dieta/análise , Flavonoides/análise , Valor Nutritivo , Fenóis/análise , Controle de Qualidade
5.
J Agric Food Chem ; 60(31): 7682-9, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22800200

RESUMO

Seven grades of black tea [high-quality black tea (grades 1-3) and low-quality black tea (grades 4-7)], processed by ÇAYKUR Tea Processing Plant (Rize, Turkey), were examined for their proximate composition, dietary fiber, minerals, and water-soluble vitamins as well as total phenolic content, various antioxidant assays, phenolics (flavanols, alkoloids, condensed phenolics, and phenolic acids), chlorophylls, and carotenoids. Some variations, albeit to different extents, were observed (p < 0.05) among these parameters in seven grades of black tea. With respect to proximate composition, dietary fiber was the predominant compound (ranging from 49.68 to 54.31 g/100 g), followed by protein, carbohydrate, and, to a lesser extent, ash, moisture, and fat. Thirteen minerals, four water-soluble vitamins, six flavanols, two alkoloids, three condensed phenolics, one phenolic acid, two chlorophylls, and two carotenoids were identified in the seven grades of black tea. Total phenol content ranged from 7.52 to 8.29 g of gallic acid equivalents (GAE)/100 g, being lowest in grade 6 and highest in grade 1. With regard to antioxidant activities, a large variation in oxygen radical absorbance capacity (ORAC) values was observed among all grades of black tea (ranging from 777 µmol of trolox equivalents (TE)/g in grade 7 to 1210 µmol of TE/g in grade 3). The present work suggests that high- and low-quality black teas should not be distinguished on the basis of their nutritional and functional characteristics. The combination of nutritional compounds together with functional characteristics renders combination effects that provide the characteristic quality of each grade of black tea.


Assuntos
Camellia sinensis/química , Extratos Vegetais/análise , Chá/química , Ácido Gálico/análise , Hidroxibenzoatos/análise , Valor Nutritivo , Turquia , Vitaminas/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...