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1.
Molecules ; 25(21)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126733

RESUMO

Lavender flowers were used in this study as a source of phytochemicals as naturally occurring antioxidants. Two different extraction techniques were applied, such as ultrasound-assisted (UAE) and supercritical fluids (SCE) methods. The comparative evaluation of the phytochemicals profile evidenced a higher content of chlorophyll a and b of 5.22 ± 0.12 mg/g dry weight (D.W.) and 2.95 ± 0.16 mg/g D.W, whereas the carotenoids content was 18.24 ± 0.04 mg/g D.W. in the SCE extract. Seven main compounds were found in both extracts: ß-linalool, eucalyptol, linalool acetate, ß-trans-ocimene, and limonene in SCE and linalool acetate, ß-linalool, 6-methyl-2-(2-oxiranyl)-5-hepten-2-ol, linalool oxide, lavandulyl acetate and camphor in UAE. The (n-3) acids had a higher contribution in SCE. The extracts were microencapsulated in different combinations of wall materials based on polysaccharides and milk proteins. The four variants showed different phytochemical and morphological profiles, with a better encapsulating efficiency for proteins (up to 98%), but with a higher content of encapsulated carotenoids for polysaccharides, the latter showing remarkable antimicrobial activity against selected microorganisms. Carboxymethyl cellulose and whey proteins led to a double encapsulation of lipophilic compounds. The powders were tested in two food matrices as ingredients, with multiple targeted functions, such as flavoring, antimicrobial, antioxidant activity that can successfully replace synthetic additives.


Assuntos
Alimentos , Lavandula/química , Compostos Fitoquímicos/farmacologia , Cápsulas , Flores/química , Compostos Fitoquímicos/química
2.
Phytochem Anal ; 25(2): 161-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24259292

RESUMO

INTRODUCTION: The characteristic flavour of tomato is given by a complex mixture of sugars, acids, amino acids, minerals and volatile metabolites. Of these, volatile compounds are considered to greatly influence the flavour of tomato fruits. The volatile aroma compounds and phytochemical content of tomatoes are dependent on genotype, environmental conditions and cultural practices, and can thus be used for cultivar discrimination. OBJECTIVE: To assess the possibility of using the volatile profile of tomato to fingerprint and discriminate different tomato cultivars based on an 'in-tube extraction' technique coupled to gas chromatography, combined with mass spectrometry (ITEX/GC-MS) and a chemometric approach. RESULTS: Using the ITEX/GC-MS technique, 61 volatiles were analysed and separated from tomato cultivars, with 58 being identified. The main volatiles identified in all tomato cultivars were: hexanal, trans-2-hexenal, 1-hexanol, 3-pentanone, 3-methylbutanol, 2-methylbutanol, 3-methylbutanal and 6-methyl-5-hepten-2-one. The lycopene content and total phenolic compound content of the tomato cultivars varied between 36.78 and 73.18 mg/kg fresh weight (fw) and from 119.4 to 253.7 mg of gallic acid equivalents (GAE) per kilogram fresh weight, respectively. Volatile fingerprint and phytochemical composition led to a good differentiation between tomato cultivars, with the first two principal components explaining 89% of the variance in the data. CONCLUSION: The tomato cultivars studied were easily discriminated based on their characteristic volatile profile that was obtained using the reliable ITEX/GC-MS technique. Principal component analysis revealed, in addition to volatile compounds, the important role played by the total phenolic content in tomato cultivar discrimination, which is highly correlated with phenotypic and biochemical differences between tomato cultivars.


Assuntos
Antioxidantes/análise , Carotenoides/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fenóis/análise , Compostos Orgânicos Voláteis/análise , Antioxidantes/isolamento & purificação , Carotenoides/isolamento & purificação , Análise por Conglomerados , Frutas/química , Licopeno , Solanum lycopersicum/química , Solanum lycopersicum/classificação , Fenóis/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Análise de Componente Principal , Especificidade da Espécie , Compostos Orgânicos Voláteis/isolamento & purificação
3.
Phytochem Anal ; 24(4): 319-28, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23319448

RESUMO

INTRODUCTION: The health benefits of sea buckthorn (Hippophae rhamnoides L.) are well documented due to its rich content in bioactive phytochemicals (pigments, phenolics and vitamins) as well as volatiles responsible for specific flavours and bacteriostatic action. The volatile compounds are good biomarkers of berry freshness, quality and authenticity. OBJECTIVE: To develop a fast and efficient GC-MS method including a minimal sample preparation technique (in-tube extraction, ITEX) for the discrimination of sea buckthorn varieties based on their chromatographic volatile fingerprint. MATERIAL AND METHODS: Twelve sea buckthorn varieties (wild and cultivated) were collected from forestry departments and experimental fields, respectively. The extraction of volatile compounds was performed using the ITEX technique whereas separation and identification was performed using a GC-MS QP-2010. Principal component analysis (PCA) was applied to discriminate the differences among sample composition. RESULTS: Using GC-MS analysis, from the headspace of sea buckthorn samples, 46 volatile compounds were separated with 43 being identified. The most abundant derivatives were ethyl esters of 2-methylbutanoic acid, 3-methylbutanoic acid, hexanoic acid, octanoic acid and butanoic acid, as well as 3-methylbutyl 3-methylbutanoate, 3-methylbutyl 2-methylbutanoate and benzoic acid ethyl ester (over 80% of all volatile compounds). Principal component analysis showed that the first two components explain 79% of data variance, demonstrating a good discrimination between samples. CONCLUSION: A reliable, fast and eco-friendly ITEX/GC-MS method was applied to fingerprint the volatile profile and to discriminate between wild and cultivated sea buckthorn berries originating from the Carpathians, with relevance to food science and technology.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Hippophae/química , Compostos Orgânicos Voláteis/análise , Butiratos/análise , Caproatos/análise , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Ésteres/análise , Análise de Alimentos/métodos , Frutas/química , Análise de Componente Principal , Romênia
4.
Plant Foods Hum Nutr ; 68(3): 313-21, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23817957

RESUMO

The profile of glucosinolates in relation to the antioxidant capacity of five Brassica vegetables (Broccoli, Cauliflower, Kohlrabi, White and Red Cabbage) grown by organic and conventional agricultural practices in Transylvania region-Romania, were determined and compared. The qualitative and quantitative compositions of glucosinolates were determined by HPLC-PDA technique. The antioxidant capacity was comparatively determined by ABTS, DPPH, FRAP and Folin-Ciocalteu assays. The highest glucosinolates levels were found in the Broccoli samples grown under conventional practices (14.24 µmol/g dry weight), glucoraphanin, glucobrassicin and neo-glucobrassicin being the major components. The total glucosinolates content was similar in Kohlrabi and Cauliflower (4.89 and 4.84 µmol/g dry weight, respectively), the indolyl glucosinolates were predominant in Kohlrabi, while the aliphatic derivatives (sinigrin and glucoiberin) were major in Cauliflower. In Cabbage samples, the aliphatic glucosinolates were predominat against indolyl derivatives, glucoraphanin and glucoiberin being the main ones in Red Cabbage. The principal component analysis was applied to discriminate among conventional and organic samples and demonstrated non-overlaps between these two agricultural practices. Meanwhile it was shown that glucosinolates may represent appropriate molecular markers of Brassica vegetables, their antioxidant capacity being higher in organic crops, without significant differences among different Brassica varieties.


Assuntos
Agricultura/métodos , Antioxidantes/análise , Brassica/química , Brassica/crescimento & desenvolvimento , Glucosinolatos/análise , Agricultura Orgânica/métodos , Cromatografia Líquida de Alta Pressão , Imidoésteres/análise , Oximas , Romênia , Sulfóxidos
5.
Nutrients ; 12(10)2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33050561

RESUMO

Nowadays, one of the most important research directions that concerns the scientific world is to exploit the earth's resources in a sustainable way. Considering the increasing interest in finding new sources of bioactive molecules and functional products, many research studies focused their interest on demonstrating the sustainability of exploiting marine macroalgal biomass as feedstock for wastewater treatment and natural fertilizer, conversion into green biofuels, active ingredients in pharmaceutical and nutraceutical products, or even for the production of functional ingredients and integration in the human food chain. The objective of the present paper was to provide an overview on the recent progress in the exploitation of different macroalgae species as a source of bioactive compounds, mainly emphasizing the latter published data regarding their potential bioactivities, health benefits, and industrial applications.


Assuntos
Biomassa , Alga Marinha/química , Anti-Infecciosos , Biocombustíveis , Produtos Biológicos , Suplementos Nutricionais , Fertilizantes , Compostos Fitoquímicos , Polissacarídeos , Purificação da Água
6.
Polymers (Basel) ; 12(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861657

RESUMO

Edible coatings and films represent an alternative packaging system characterized by being more environment- and customer-friendly than conventional systems of food protection. Research on edible coatings requires multidisciplinary efforts by food engineers, biopolymer specialists and biotechnologists. Entrapment of probiotic cells in edible films or coatings is a favorable approach that may overcome the limitations linked with the use of bioactive compounds in or on food products. The recognition of several health advantages associated with probiotics ingestion is worldwide accepted and well documented. Nevertheless, due to the low stability of probiotics in the food processing steps, in the food matrices and in the gastrointestinal tract, this kind of encapsulation is of high relevance. The development of new and functional edible packaging may lead to new functional foods. This review will focus on edible coatings and films containing probiotic cells (obtaining techniques, materials, characteristics, and applications) and the innovative entrapment techniques use to obtained such packaging.

7.
Chem Cent J ; 12(1): 88, 2018 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-30078060

RESUMO

The advanced biochemical characterisation of green, red lentil and wheat flours was performed by assessing their folic acid content as well as individual minerals, amino acids, fatty acids and volatile compounds. Moreover, a nutritionally improved wheat-lentil composite flour, with a content of 133.33 µg of folic acid/100 g, was proposed in order to assure the folic acid daily intake (200 µg) for an adult person. The wheat and lentil flours percentages used for the composite were calculated by using the equations for total material balance and folic acid content material balance. Bread was selected as model food for the composite flour due to its high daily intake (~ 250 g day-1) and to its great potential in biofortification. By this algorithm, two composite flours were developed, wheat-green lentil flour (22.21-77.79%) and wheat-red lentil flour (42.62-57.38%), their advanced biochemical characteristics being predicted based on the determined compositions of their constituents. The baking behaviour of the new developed wheat-lentils composite flours with optimised folic acid content was tested. In order to objectively compare the bread samples, texture profile analysis was considered the most relevant test. A good baking behaviour was observed for the wheat-red lentil bread, while for the wheat-green lentil composite flour, encouraging results were obtained.

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