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1.
J Chromatogr A ; 1730: 465104, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38905947

RESUMEN

For the first time, a method for the simultaneous analysis of fifteen polycyclic aromatic hydrocarbons (PAHs), including light and heavy PAHs, in açaí-based food products (AFPs) was developed using vacuum-assisted sorbent extraction (VASE) combined with gas chromatography-mass spectrometry (GC-MS). The method requires no organic solvents and is amenable to full automation. To achieve optimal analytical extraction conditions, VASE parameters including stirring rate, extraction time, desorption temperature, desorption time, preheat time, and preheat temperature were optimized using sequential multivariate optimization. The method was validated and yielded limits of quantification below 1 µg kg-1 for all analytes, with recoveries ranging from 65 % to 112 % and good precision (≤11 % relative standard deviation). Additionally, the greenness and practical aspects of the method were investigated using the Green Analytical Procedure Index (GAPI), eco-scale, and the Blue Applicability Grade Index (BAGI), respectively. The VASE-GC-MS approach is suitable for routine analysis and exhibits characteristics of a green analytical method. No PAHs were detected above the limits of detection in thirty samples of AFPs.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Hidrocarburos Policíclicos Aromáticos , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Vacio , Extracción en Fase Sólida/métodos , Contaminación de Alimentos/análisis , Tecnología Química Verde/métodos , Análisis de los Alimentos/métodos , Reproducibilidad de los Resultados
2.
J Chromatogr A ; 1726: 464967, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38749275

RESUMEN

Infant formulas (IF) can contain harmful chemical substances, such as pesticides and mycotoxins, resulting from the contamination of raw materials and inputs used in the production chain, which can cause adverse effects to infants. Therefore, the quick, easy, cheap, effective, rugged, and safe (QuEChERS) methodology prior ultra-high performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPL-QqQ-MS/MS) analysis was applied for the determination of 23 contaminants, in 30 samples of Brazilian IF. The method was validated in terms of limit of detection (0.2 to 0.4 µg/kg), limits of quantification (1 and 10 µg/kg), and recovery (64 % to 122 %); precision values, in terms of relative standard deviation (RSD), were ≤ 20 %. Fenitrothion, chlorpyrifos, and bifenthrin were the pesticides detected in the samples, but the values did not exceed the limit set by the European Union (EU), and ANVISA, and they were detected under their limits of quantification. Additionally, suspect screening and unknown analysis were conducted to tentatively identify 32 substances, including some compounds not covered in this study, such as pesticides, hormones, and veterinary drugs. Carbofuran was identified, confirmed and quantified in 10 % of the samples.


Asunto(s)
Contaminación de Alimentos , Fórmulas Infantiles , Límite de Detección , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Brasil , Fórmulas Infantiles/química , Contaminación de Alimentos/análisis , Plaguicidas/análisis , Humanos , Residuos de Plaguicidas/análisis , Reproducibilidad de los Resultados , Micotoxinas/análisis , Lactante , Piretrinas/análisis
3.
Food Chem ; 444: 138593, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38310774

RESUMEN

In this study, polymeric ionic liquids featuring different functional moieties were applied as sorbent coatings in direct-immersion solid-phase microextraction (DI-SPME) for the extraction of 2-methylimidazole (2-MI) and 4-methylimidazole (4-MI) from açaí-based food products followed by gas chromatography-mass spectrometry (GC-MS) analysis. The analytical method was optimized using a sequential experimental design. Variables used in GC-MS such as desorption time, as well as for SPME-DI, including extraction time, extraction temperature, incubation time of extraction, amount of NaCl in the extract, and stirring rate, were optimized. The fitness-for-purpose of the method was verified by the linearity of matrix-matched calibration curves (R2 ≥ 0.9921), adequate recoveries (81.7-89.7 %), and precision (relative standard deviations ≤11.2 %). The method was applied to twenty-five samples of açaí-based food products. 4-MI was found in four samples whereas 2-MI was not detected above the limit of detection. The method was found to be suitable for quality control analysis.


Asunto(s)
Imidazoles , Líquidos Iónicos , Microextracción en Fase Sólida , Microextracción en Fase Sólida/métodos , Líquidos Iónicos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Polímeros/química , Límite de Detección
4.
Heliyon ; 10(2): e24054, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38288015

RESUMEN

The rapid growth of the world population has increased the demand for new food sources, constituting a major challenge concerning the maximum use of existing food resources. The fruits of Amazonian palm trees have excellent nutritional composition and bioactive compounds. This review highlights four fruits of Amazonian palm trees that are still little explored by the food industry: açai (Euterpe oleracea), pupunha (Bactris gasipaes), buriti (Mauritia flexuosa), and tucumã (Astrocaryum aculeatum). This paper aims to inspire new ideas for researching and developing products for the food industry. It also explores the impacts of Amazonian palm fruits on health, highlighting their role in disease prevention through their nutritional effects.

5.
J Sep Sci ; 46(16): e2300069, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37271898

RESUMEN

In this work, a cost-effective gas chromatography-mass spectrometry method was validated for the analysis of twenty-five pesticide residues in herbs and infusions using a quick, easy, cheap, effective, rugged, and safe procedure or a dispersive liquid-liquid microextraction method, respectively. Figures of merit of the method showed good accordance with current guidelines. From the 58 herb samples studied (pertaining to 20 different species), 80% presented at least one detectable pesticide, with 62% of them above the maximum residual level. Results showed that pesticide residues from naturally contaminated herbs were not transferred at a significant rate to the herbal infusions. When a control assay was conducted by spiking a blank herb sample with a large amount of each pesticide (7 mg/L) 15 analytes were detected below the limit of quantification in the infusion.


Asunto(s)
Microextracción en Fase Líquida , Residuos de Plaguicidas , Residuos de Plaguicidas/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos
6.
Food Res Int ; 167: 112593, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37087222

RESUMEN

Plasma is considered by several researchers to be the fourth state of matter. Cold plasma has been highlighted as an alternative to thermal treatments because heat induces less degradation of thermolabile bioactive compounds, such as natural pigments. In this review, we provide a compilation of the current information about the effects of cold plasma on natural pigments, such as the changes caused by plasma to the molecules of chlorophylls, carotenoids, anthocyanins, and betalains. As a result of the literature review, it is noted that can degrade cell membrane and promote damage to pigment storage sites; thereby releasing pigments and increasing their content in the extracellular space. However, the reactive species contained in the cold plasma can cause degradation of the pigments. Cold plasma is a promising technology for extracting pigments; however, case-by-case optimization of the extraction process is required.


Asunto(s)
Antocianinas , Gases em Plasma , Antocianinas/metabolismo , Carotenoides/metabolismo , Betalaínas , Clorofila
7.
Food Res Int ; 167: 112697, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37087263

RESUMEN

A protocol was optimized to determine the volatile profile from monovarietal virgin olive oil (VOO) by multiple headspace solid-phase microextraction (MHS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. For this, a Plackett-Burman (PB) and central composite rotational designs (CCRD) were used to define the best condition of extraction. Moreover, fatty acids profile and principal component analysis (PCA) was used to identify markers among the cultivars. The amount of 0.1 g of sample was enough to express the volatile composition of the olive oils by MHS-SPME. Volatile compounds [nonanal, (Z)-3-Hexen-1-ol, (Z)-3-Hexenyl Acetate, Hexyl Acetate, 3-Methylbutyl Acetate, (E)-2-Hexen-1-ol, (E)-2-Hexenyl Acetate] and fatty acids [C17:1, C18, C18:1, C18:2] were those reported such as the markers in the varieties of olive oils. The PCA analysis allowed the classification of the most representative volatiles and fatty acids for each cultivar. Through two principal components was possible to obtain 81.9% of explanation of the variance of the compounds. The compounds were quantified using a validated method. The MHS-SPME combined with multivariate analysis showed a promising tool to identify markers and for the discrimination of olive oil varieties.


Asunto(s)
Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles , Microextracción en Fase Sólida/métodos , Aceite de Oliva/química , Brasil , Quimiometría , Compuestos Orgánicos Volátiles/análisis , Ácidos Grasos/análisis
8.
Carbohydr Polym ; 302: 120379, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36604057

RESUMEN

The occurrence of persistent organic pollutants in aquatic bodies, namely polycyclic aromatic hydrocarbons (PAHs), has been increasingly detected. The presence of such contaminants represents a serious threat to human health due to their toxicity. Therefore, aiming to provide a novel and efficient alternative for PAHs' removal from water, the present study assesses the effect of oligo(ß-pinene) blended with chitosan for the adsorption of these pollutants. Oligo(ß-pinene) with phenyl end-groups was synthesized by organocatalyzed atom transfer radical polymerization (O-ATRP) and incorporated in different concentrations (6, 12, and 18 %) to chitosan films. The oligo(ß-pinene) loading in the chitosan matrix impressively improved this polysaccharide adsorption capacity. The formulation containing 12 % of oligomer demonstrated a contaminant removal performance three times higher (298.82 %) than pure chitosan during only 1 h of the decontamination process. Adsorption isotherms showed an improved uptake of PAHs with the increase of the contaminants' concentration in the aqueous media due to the formation of a higher concentration gradient. Additionally, a comprehensive characterization of oligo(ß-pinene)/chitosan formulation was performed to provide a better understanding of the interactions between the components of the blends. Overall, it was concluded that oligo(ß-pinene)/chitosan blends can be used as a high-performance and sustainable alternative for PAHs removal.


Asunto(s)
Quitosano , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Humanos , Adsorción , Agua
9.
Plant Foods Hum Nutr ; 77(3): 340-344, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35902483

RESUMEN

Phenolic compounds in camu-camu (Myrciaria dubia) have received interest due to their health-promoting effects. However, these compounds have been poorly investigated in the different parts of the camu-camu fruit (pulp, peel, and seeds). This study aimed to optimize the solvent composition for extraction of phenolic compounds from pulp, peels, and seeds of camu-camu through a simplex-centroid mixture design. Then, the profile of phenolic compounds in samples of camu-camu pulp, peels, and seeds from different regions in Brazil and South America was determined by UPLC-ESI-MS/MS. Aqueous ethanol (80%, v/v) yielded the highest extraction for the pulp and peel, while aqueous methanol (50%, v/v) was selected for the seed. Camu-camu parts had p-coumaric acid, catechin, epicatechin, luteolin, rutin, and quercetin, with catechin as the major compound in the pulp, peels, and seeds of all the evaluated samples. The peel showed lower concentrations of these compounds compared with the pulp and the seed; the content of phenolic compounds also differed according to the geographic region. These results broaden the knowledge on phytochemical extraction and composition of camu-camu pulp, peel, and seed and may guide future applications of their extracts in the food industry.


Asunto(s)
Catequina , Myrtaceae , Brasil , Catequina/análisis , Frutas/química , Myrtaceae/química , Fenoles/análisis , Extractos Vegetales/química , Espectrometría de Masas en Tándem
10.
Food Res Int ; 150(Pt A): 110788, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34865803

RESUMEN

An analytical method was developed to determine volatile compounds (VC) that contribute to the aroma of cheese from Serra da Canastra (Brazil) and evaluate them in three ripening stages (fresh, short-ripened, and ripened) via headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC). Proximate and fatty acid compositions were determined to observe whether there would be changes during ripening. Multivariate designs were applied to optimize the extraction parameters of volatile compounds and assisted by GC olfactometry (GC-O) and chemometrics. The adopted strategy revealed that the best extraction condition requires 10 min of equilibration, 75.2 min of fiber exposure at 40 °C, and 1 g of sample. The data obtained evidenced the alteration of the abundance of volatile compounds, fatty acids, and proximate composition of Canastra cheese during ripening. The fatty acid profile of the samples was mainly composed of palmitic, oleic, and stearic acids. This dairy product is rich in volatile compounds and formed primarily by alcohols (n = 14), acids (n = 13), and esters (n = 11). Olfactometry indicated that the VCs that most affected the aroma of ripened Canastra cheese were acetic acid, isobutyric acid, butanoic acid, and ethyl hexanoate. The method developed effectively discriminated against Canastra cheeses at their different ripening stages.


Asunto(s)
Queso , Compuestos Orgánicos Volátiles , Queso/análisis , Quimiometría , Cromatografía de Gases y Espectrometría de Masas , Odorantes/análisis , Olfatometría , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/análisis
11.
Food Chem ; 364: 130350, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34153595

RESUMEN

This study investigated the vitamin C content, total phenolic compounds (TPC), and the potential bioactivities (antioxidant, antiproliferative, antibacterial activities, and inhibition capacity against N-nitrosation) of seven neglected and underutilized species (NUS): culantro (Eryngium foetidum), false roselle (Hibiscus acetosella), roselle (Hibiscus sabdariffa), tree basil (Ocimum gratissimum), Barbados Gooseberry (Pereskia aculeata), purslane (Portulaca oleracea), and tannia (Xanthosoma sagittifolium). Phenolic-rich extracts were obtained by a sequential optimization strategy (Plackett-Burman and Central Composite Design). O. gratissimum presented the highest TPC and X. sagittifolium the greater total vitamin C content. Overall, the plant extracts presented promising bioactive capacities, as scavenging capacity against HOCl, H2O2 and ROO• induced oxidation. P. oleracea demonstrated the highest cytostatic effect against ovarian and kidney tumor cells. O. gratissimum effectively inhibited S. Choleraesuis growth. Maximum inhibition on n-nitrosation was showed by O. gratissimum and E. foetidum. These results highlight the studied NUS as sources of potential health-promoting compounds.


Asunto(s)
Hibiscus , Peróxido de Hidrógeno , Brasil , Extractos Vegetales/farmacología , Hojas de la Planta
12.
J Food Sci ; 86(5): 1599-1619, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33822383

RESUMEN

Ilex paraguariensis is a perennial plant used in the production of mate tea, "chimarrão" and "tererê," cosmetics, and other food products. Its leaves are harvested every 12 or 18 months. Approximately 2 to 5 tons of residue are generated per hectare during the harvest. The bioactive composition of this residue has not been characterized to date. Therefore, this paper presents for the first time, the simultaneous characterization of the bioactive compounds of the leaves, thin branches, and thick branches (residue) from I. paraguariensis grown under two cultivation systems: "full sun" and "shaded." The identification and quantification of the compounds was performed using high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometer (HPLC-ESI-QTOF-MS). Consequently, 35 compounds were identified. The average dry weight of phenolic compounds in the residue was 4.1 g/100 g, whereas that in the bark of the residue was 12.9 g/100 g, which was similar to the content found in leaves. The same compounds were identified in the two cultivation systems but with a difference in their contents. While the "full sun" cultivation had a higher content of phenolic acids, the "shaded" cultivation had a higher content of flavonoids and saponins. It was found that the I. paraguariensis residue, particularly the bark, is rich in bioactive compounds, such as quinic, 3-caffeoylquinic, 5-cafefoylquinic, 3,5-dicaffeoylquinic, and 4,5-dicaffeoylquinic acids as well as rutin, and their contents vary according to the cultivation system. Therefore, this residue is an underutilized natural resource with a potential for industrial applications. PRACTICAL APPLICATION: Yerba mate producers will be able to choose the best cultivation system ("full sun" or "shaded") to increase the content of bioactive compounds. New products may be developed with yerba mate residue due to its high concentration of compounds that are beneficial to the human health. New destinations may be applied to yerba mate residue from the harvest pruning, adding commercial value to this unexplored natural resource.


Asunto(s)
Ilex paraguariensis/química , Fitoquímicos/análisis , Corteza de la Planta/química , Extractos Vegetales/química , Hojas de la Planta/química , Cromatografía Líquida de Alta Presión , Humanos , Espectrometría de Masa por Ionización de Electrospray/métodos
13.
Anal Bioanal Chem ; 413(11): 2903-2912, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33709193

RESUMEN

Phthalic acid esters (PAEs) and adipates are plasticizers with high applicability in several products and building materials (e.g. cosmetics, packing) very persistent in the environment, features which render them ubiquitous pollutants. These substances can contaminate food through the environment (water, air, and soil) and/or migration from packaging materials, which creates a health concern due to their toxicity. This paper describes an eco-friendly dispersive liquid-liquid microextraction (DLLME) procedure to extract five phthalates and bis(2-ethylhexyl) adipate (DEHA) from bottled herbal-based beverages followed by GC-MS/MS quantification. The method showed low limits of detection (5.0-13 µg L-1) and quantification (20-35 µg L-1), good inter- and intraday precision (RSD < 19%), and recoveries ranging from 82 to 111%. It was applied to 16 real samples, of which 13 showed the presence of at least one of the analytes under study. Additionally, an exposure assessment was performed, and resulted in a hazard quotient less than 1 (HQ < 1) for all analytes. Therefore, PAEs and DEHA found in samples do not pose a health issue.


Asunto(s)
Adipatos/análisis , Bebidas Gaseosas/análisis , Ácidos Ftálicos/análisis , Contaminantes Ambientales/análisis , Ésteres , Embalaje de Alimentos , Cromatografía de Gases y Espectrometría de Masas/métodos , Límite de Detección , Microextracción en Fase Líquida/métodos , Ácidos Ftálicos/química , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
14.
J Chromatogr A ; 1635: 461757, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33302139

RESUMEN

A simple and effective analytical method to determine six contaminants, including five benzophenones (BP, BP-1, BP-3, BP-8, and BP-12) and bisphenol A (BPA) in infant formulas was developed in this study. For this, a sequential experimental design was used to optimize the extraction and cleanup method using low temperature partition (LTP) combined with dispersive solid phase extraction (dSPE). The effect of primary secondary amine (PSA), sodium chloride (NaCl), graphitized carbon black (GCB), octadecyl (C18), strong anion exchanger (SAX), water, acetonitrile (ACN) and, ultrasound (US) time were evaluated using a sequential design of experiments including a Plackett-Burman, a central composite rotatable design, and the Derringer and Suich's tool. The method was validated, and it showed a limit of quantification varying from 0.06 to 2 mg.kg-1, good precision (< 20% RSD), and recovery (52-106%). The method proposed was applied to twenty-five samples of commercial infant formulas.


Asunto(s)
Compuestos de Bencidrilo/aislamiento & purificación , Benzofenonas/aislamiento & purificación , Análisis de los Alimentos/métodos , Fórmulas Infantiles/química , Fenoles/aislamiento & purificación , Extracción en Fase Sólida , Acetonitrilos , Compuestos de Bencidrilo/análisis , Benzofenonas/análisis , Frío , Análisis de los Alimentos/instrumentación , Humanos , Lactante , Límite de Detección , Fenoles/análisis
15.
J Chromatogr A ; 1635: 461736, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33254001

RESUMEN

Ready-to-drink teas can provide, if properly packaged, the taste and wellness character of traditional teas. Nevertheless, in tea processing, there may be several contaminations, among which polycyclic aromatic hydrocarbons (PAHs), anthropogenic contaminants that can present carcinogenic and mutagenic properties. In this work, a novel low-density deep eutectic solvent-based dispersive liquid-liquid microextraction (LDDES-DLLME) procedure followed by gas chromatography tandem mass spectrometry (GC-MS/MS) was optimized for analysis of 15 polycyclic aromatic hydrocarbons (PAHs) in ready-to-drink herbal-based beverages. The new deep eutectic solvent (DES) was synthesized with natural compounds (camphor and hexanoic acid). Several parameters of the extraction procedure such as type and volume of extraction solvent, type, volume of dispersive solvent, and time of extraction were evaluated to achieve the highest yield and to attain the lowest detection limits. The validated method showed very low limits of detection (0.01 µg L-1) and quantification (0.2 µg L-1), good inter- and intra-day precisions (RSD<16.87%), and recoveries higher than 69%. The method was applied to 16 type of samples and it was found total PAHs levels ranging from 0.20 to 1.82 µg L-1. The developed LDDES-DLLME showed a reliable and innovative alternative for the extraction of PAHs from beverages, cost-effective and environmentally friendly, and providing a satisfactory throughput.


Asunto(s)
Bebidas Gaseosas/análisis , Análisis de los Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas , Microextracción en Fase Líquida/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Límite de Detección , Contaminantes Químicos del Agua/análisis
16.
Food Res Int ; 137: 109652, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33233231

RESUMEN

The encapsulation efficiency of spray-dried cocona pulp encapsulated with a blend of maltodextrin (MD) and hydrolyzed collagen (HC) (CP-ENC) and the stability, color parameters, antioxidant capacity (FRAP and ABTS), and 5-caffeoylquinic acid content were evaluated through 120 days of storage, at every 15 days, at 25 and 35 °C. The results of CP-ENC were compared to those of pure freeze-dried cocona pulp (CP-nENC). The sorption isotherms and glass transition temperatures (Tg) were determined in order to evaluate the stability of the cocona powder. The GAB model fitted well the experimental data for moisture sorption of samples. The high Tg for CP-ENC (132.02 °C) was attributed to the high molecular weight of encapsulating agents. The encapsulation efficiency and color parameters for CP-ENC kept constant values for 120 days. A loss of 30% in the antioxidant capacity occurred on day 75 for CP-ENC. The values of retention of 5-CQA for CP-ENC (83% and 68% when stored at 25 and 35 °C, respectively) were greater than those observed for CP-nENC. At 25 °C, stored CP-ENC had a higher retention and a longer half-life of 5-CQA (14.4 months) than CP-nENC. The results suggest that it is suitable to microencapsulate cocona pulp with MD and HC to improve protection of antioxidant compounds, throughout storage at 25 °C.


Asunto(s)
Colágeno , Polisacáridos , Polvos , Ácido Quínico/análogos & derivados
17.
Bioresour Technol ; 306: 123184, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32238318

RESUMEN

LEDs have specific wavelengths that can positively influence the production of microalga biomass and biomolecules of interest. Filling the gaps in the literature, this study evaluated the effect of different LED wavelengths and photoperiods on protein productivities and free amino acid (FAA) profile of Spirulina sp. LEB 18 cultures. The best protein productivity results were obtained in red and green LED cultures using integral and partial photoperiods, respectively. In these experiments, protein productivities increased 2 and 1.6 times, respectively, compared to the control culture using fluorescent light. Green LEDs in partial photoperiod provided also the highest concentrations of essential and non-essential FAA, about 1.8 and 2.3 times higher, respectively, than control cultures. LEDs showed to be a promising sustainable light source for increasing protein productivity and FAA concentration in Spirulina sp. LEB 18 cultures.


Asunto(s)
Microalgas , Spirulina , Aminoácidos , Biomasa
18.
Biol Trace Elem Res ; 197(2): 676-682, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31907800

RESUMEN

The concentrations of 3,4-dihydroxybenzoic acid, caffeic acid, catechin, chlorogenic acid, epicatechin, gallic acid, p-coumaric acid, quercetin, rutin, ferulic acid, and the major metals in graviola (Annona muricata), atemoya (A. squamosa x A. cherimola), fruta do conde (A. squamosa), biribá (Rollinia mucosa), and the North American pawpaw (Asimina triloba) were determined by UPLC-ESI (-)-MS/MS. It enabled the identification and quantification of phenolic compounds. Catechin was only found in atemoya, at a concentration of 38.6 µg/g-dw. Only 3,4-dihydroxybenzoic acid was found in the fruit pulps of all five fruits analyzed. Atemoya stands out for not only having catechin but also for having much more epicatechin (239 µg/g-dw) than the other fruits. At the same time, graviola had more p-coumaric acid (62.6 µg/g-dw), and the North American pawpaw had more chlorogenic acid (48.1 µg/g-dw) than the other fruits. Metals were determined by ICP equipped with axially viewed plasma. All five fruit pulps had relatively high levels of potassium, with concentrations ranging from 7640 to 15,000 µg/g-dw, with pawpaw being the lowest and atemoya being the highest. The concentrations of other metals ranged from Ca 547 to 1110, Na 14.3 to 123, P 1210 to 1690, Mg 472 to 980, Mn 1.86 to 5.27, and Zn 5.55 to 7.32 µg/g-dw. All five fruits in the Annonaceae family that were analyzed in this study have several phenolic compounds in them and were good sources of potassium, calcium, phosphorus, and magnesium.


Asunto(s)
Annonaceae , Frutas , Antioxidantes , Frutas/química , Fenoles/análisis , Extractos Vegetales , Quercetina , Espectrometría de Masas en Tándem
19.
Plant Foods Hum Nutr ; 75(1): 70-75, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31848853

RESUMEN

Tamarind fruits are consumed worldwide and their seeds have an underexploited potential. We assessed the effect of the addition of a freeze-dried aqueous of extract tamarind seed (FAE) at three concentration levels (0.3, 1.15 and 2%) on the antioxidant capacity (DPPH, ABTS, FRAP and ORAC) and concentrations of total phenolic compounds in tamarind pulp. Conditions used to prepare the aqueous extracts were established using multivariate optimization. Moreover, nectars prepared from pulps combined with FAE were subjected to sensory tests. Tamarind fruits from three geographic regions in Brazil (Minas Gerais, São Paulo and Bahia) that were harvested in 2013 and 2014 were used in the study. Generally, the freeze-dried aqueous extracts increased the concentrations of antioxidants in the pulp. The results revealed a positive correlation between the FAE concentration in the pulp and the antioxidant capacity of all samples, particularly samples from Bahia and Minas Gerais, which presented an increase of up to 1,942% in the ABTS method when 2% FAE was incorporated into the pulp, from approximately 40.1 to 209.1 mMTrolox/gdw and 13.4 to 143.4 mMTrolox/gdw, respectively. Sensory tests indicated the satisfactory acceptance and non-distinction between nectar samples to which FAE was or was not added when the FAE concentration was less than 2.3gFAE/L, regardless of the geographic origin of the samples.


Asunto(s)
Tamarindus , Antioxidantes , Brasil , Frutas , Extractos Vegetales , Néctar de las Plantas
20.
Talanta ; 207: 120301, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31594562

RESUMEN

A SPME protocol was optimised for the characterization of odorous migrants coming from baby bottles. Considering this, a Plackett-Burman design to select variables and a central composite rotatable design to define the optimal conditions were used. The method proposed by Derringer and Suich was used to simultaneously optimise the responses. After validation, the analytical method was used to characterise volatile migrants from baby bottles made of polypropylene, Tritan and silicone using 50% ethanol as a simulant. 2,4-di-tert-butylphenol was identified in all samples. Forty-five compounds were identified, of which thirty-eight were odorants in silicone baby bottles. Aldehydes were mainly responsible for the unpleasant odour of silicone. Moreover, silicone showed slightly higher volatile organic compounds (%) than recommended. Odours from ketones, benzophenone derivatives and alcohols were also detected by GC-O-MS, however below the LOQ obtained in the MS detector. All migration data were below the specific migration limits.

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