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1.
Plant Foods Hum Nutr ; 79(1): 159-165, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38236453

RESUMO

Linseed represents a rich source of nutritional, functional and health-beneficial compounds. Nevertheless, the chemical composition and content of bioactive compounds may be quite variable and potentially affected by various factors, including genotype and the environment. In this study, the proximate chemical composition, lignans content and antioxidant potential of six experimentally grown linseed cultivars were assessed and compared. A diagonal cultivation trial in the University of South Bohemia Experimental Station in Ceské Budejovice, Czech Republic, was established in three subsequent growing seasons (2018, 2019 and 2020). The results showed that the cultivar and growing conditions influenced most studied parameters. The lack of precipitation in May and June 2019 negatively affected the seed yield and the level of secoisolariciresinol diglucoside but did not decrease the crude protein content, which was negatively related to the oil content. The newly developed method for lignans analysis allowed the identification and quantification of secoisolariciresinol diglucoside and matairesinol. Their content correlated positively with the total polyphenol content and antioxidant assays (DPPH and ABTS radical scavenging activity), indicating the significant contribution to the biofunctional properties of linseed. On the other hand, we did not detect minor linseed lignans, pinoresinol and lariciresinol. The results of this study showed the importance of cultivar and growing conditions factors on the linseed chemical composition and the lignans content, determining its nutritional and medicinal properties.


Assuntos
Linho , Glucosídeos , Lignanas , Antioxidantes/análise , Butileno Glicóis/análise , Butileno Glicóis/química , Butileno Glicóis/metabolismo , Linho/química , Lignanas/análise , Lignanas/química , Lignanas/metabolismo
2.
J Food Sci ; 88(12): 5278-5290, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37889085

RESUMO

Secoisolariciresinol diglucoside (SDG) and tracheloside (TCL) are the main lignan components of flaxseed cake and safflower seed cake, which are by-products of oil extraction. Both SDG and TCL are metabolized into mammalian lignan enterolactone (EL) with the involvement of intestinal bacteria. In this research, we evaluated the anti-osteoporosis effects of SDG and the in vivo metabolites EL and enterodiol (ED) prepared in our previous work, as well as the newly isolated chemical constituents from safflower seed, including TCL, the lactone ring opening product of TCL (OTCL) and two alkaloids on the alloxan-induced zebrafish model. All the compounds showed significant anti-osteoporosis effects at 80 µM, with p < 0.05 for EL and p < 0.001 for other compounds compared with the model. SDG and TCL showed the most significant and concentration-dependent effects, with p < 0.001 compared with model at 20 µM. The alkaloids, N-coumaroylserotonin glucoside and N-feruloylserotonin glucoside, also showed anti-osteoporosis at 20 µM with p < 0.01, whereas EL, ED, and OTCL showed no significant effects. Quantitative real-time polymerase chain reaction revealed that SDG and TCL upregulated the expression of osteogenic genes Runx2, SP7, OPG, Col1a1a, Alp, ON, OPN, and OCN in alloxan-treated zebrafish. The in vivo metabolite of lignans, EL, showed significant anti-inflammatory effect (p < 0.01) at 20 µM, which might also help to combat osteoporosis and other complications caused by excessive immune response in the body. The results provided scientific data for using the oil extraction by-products as sources of anti-osteoporosis compounds. PRACTICAL APPLICATION: This study found that lignans in flaxseed cake and safflower seed cake exhibited anti-osteoporosis effects by upregulating the expression of osteogenic genes, making the oil extraction by-products sources of anti-osteoporosis compounds.


Assuntos
Alcaloides , Carthamus tinctorius , Linho , Lignanas , Animais , Linho/química , Peixe-Zebra , Aloxano/análise , Aloxano/metabolismo , Glucosídeos/análise , Mamíferos , Lignanas/farmacologia , Sementes/química , 4-Butirolactona , Butileno Glicóis/farmacologia , Butileno Glicóis/análise , Alcaloides/análise
3.
Food Chem ; 404(Pt A): 134607, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36272303

RESUMO

This research assessed the influence of pickling, fermentation, germination, and tea brewing on lignan content of a variety of food highly consumed in Malaysia. Lignans have been measured by a validated LC-MS/MS method. Secoisolariciresinol (SECO) was the most abundant compound in fermented and germinated samples. Pickling significantly decreased larisiresinol content by approximately 86 %. Fermentation increased lignan content in a mixture of flaxseed and mung beans (799.9 ± 67.4 mg/100 g DW) compared to the unfermented counterpart (501.4 ± 134.6 mg/100 g DW), whereas the fermentation of soybeans and mung beans did not significantly affect the SECO content. Germination increased lignan content, which reached its peak on day 6 of germination for all the tested matrixes. In tea brew, lignans concentration increased with brewing time reaching its highest concentration at 10 min of brewing. The results of this study expand the knowledge on the effect of processing on lignan content in food.


Assuntos
Fabaceae , Linho , Lignanas , Cromatografia Líquida , Espectrometria de Massas em Tandem , Lignanas/análise , Butileno Glicóis/análise , Chá
4.
Mar Drugs ; 20(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36135760

RESUMO

Pelagia noctiluca stings are common in Mediterranean coastal areas and, although the venom is non-lethal, they are painful. Due to its high toxicity and abundance, P. noctiluca is considered a target species for the focus of research on active ingredients to reduce the symptoms of its sting. To determine the effect of 31 substances and formulations on nematocyst discharge, we performed three tests: (1) screening of per se discharge activator solutions, (2) inhibitory test with nematocyst chemical stimulation (5% acetic acid) and (3) inhibitory test quantifying the hemolytic area. Ammonia, barium chloride, bleach, scented ammonia, carbonated cola, lemon juice, sodium chloride and papain triggered nematocyst discharge. All of them were ruled out as potential inhibitors. Butylene glycol showed a reduction in nematocyst discharge, while the formulations of 10% lidocaine in ethanol, 1.5% hydroxyacetophenone in distilled water + butylene glycol, and 3% Symsitive® in butylene glycol inhibited nematocyst discharge. These last results were subsequently correlated with a significant decrease in hemolytic area in the venom assays versus seawater, a neutral solution. The presented data represent a first step in research to develop preventive products for jellyfish stings while at the same time attempting to clarify some uncertainties about the role of various topical solutions in P. noctiluca first-aid protocols.


Assuntos
Mordeduras e Picadas , Cnidários , Venenos de Cnidários , Cifozoários , Amônia/análise , Amônia/farmacologia , Animais , Mordeduras e Picadas/prevenção & controle , Butileno Glicóis/análise , Butileno Glicóis/farmacologia , Venenos de Cnidários/análise , Venenos de Cnidários/farmacologia , Etanol/farmacologia , Hemólise , Lidocaína/farmacologia , Nematocisto/química , Papaína/farmacologia , Cifozoários/química , Cloreto de Sódio/farmacologia , Água
5.
Molecules ; 26(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361665

RESUMO

In vitro cultures of scarlet flax (Linum grandiflorum L.), an important ornamental flax, have been established as a new possible valuable resource of lignans and neolignans for antioxidant and anti-inflammatory applications. The callogenic potential at different concentrations of α-naphthalene acetic acid (NAA) and thidiazuron (TDZ), alone or in combinations, was evaluated using both L. grandiflorum hypocotyl and cotyledon explants. A higher callus induction frequency was observed on NAA than TDZ, especially for hypocotyl explants, with a maximum frequency (i.e., 95.2%) on 1.0 mg/L of NAA. The presence of NAA (1.0 mg/L) in conjunction with TDZ tended to increase the frequency of callogenesis relative to TDZ alone, but never reached the values observed with NAA alone, thereby indicating the lack of synergy between these two plant growth regulators (PGRs). Similarly, in terms of biomass, NAA was more effective than TDZ, with a maximum accumulation of biomass registered for medium supplemented with 1.0 mg/L of NAA using hypocotyls as initial explants (DW: 13.1 g). However, for biomass, a synergy between the two PGRs was observed, particularly for cotyledon-derived explants and for the lowest concentrations of TDZ. The influence of these two PGRs on callogenesis and biomass is discussed. The HPLC analysis confirmed the presence of lignans (secoisolariciresinol (SECO) and lariciresinol (LARI) and neolignan (dehydrodiconiferyl alcohol [DCA]) naturally accumulated in their glycoside forms. Furthermore, the antioxidant activities performed for both hypocotyl- and cotyledon-derived cultures were also found maximal (DPPH: 89.5%, FRAP 866: µM TEAC, ABTS: 456 µM TEAC) in hypocotyl-derived callus cultures as compared with callus obtained from cotyledon explants. Moreover, the anti-inflammatory activities revealed high inhibition (COX-1: 47.4% and COX-2: 51.1%) for extract of hypocotyl-derived callus cultures at 2.5 mg/L TDZ. The anti-inflammatory action against COX-1 and COX-2 was supported by the IC50 values. This report provides a viable approach for enhanced biomass accumulation and efficient production of (neo)lignans in L. grandiflorum callus cultures.


Assuntos
Anti-Inflamatórios/análise , Antioxidantes/análise , Butileno Glicóis/análise , Cotilédone/química , Linho/química , Furanos/análise , Hipocótilo/química , Lignanas/análise , Extratos Vegetais/análise , Biomassa , Cromatografia Líquida de Alta Pressão/métodos , Cotilédone/metabolismo , Meios de Cultura/química , Técnicas de Cultura/métodos , Linho/metabolismo , Hipocótilo/metabolismo , Ácidos Naftalenoacéticos/farmacologia , Fenóis/análise , Compostos de Fenilureia/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Tiadiazóis/farmacologia
6.
Food Chem Toxicol ; 154: 112373, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34182045

RESUMO

The safety of food contact plastic materials, including PP, PE, PET, PCT, PLA, PBT and cross-linked polyester, was assessed with regard to migrated substances. The migrated concentrations of overall migrants (OMs), terephthalic acid, acetaldehyde, 1,4-butanediol and lead, were determined according to the standards and specifications for utensils, containers and packages in Korea. Food simulants of 4% acetic acid, water and n-heptane were used for the analysis of the substances. The dietary exposures of terephthalic acid, acetaldehyde and 1,4-butanediol were assessed using the dietary concentrations and the food consumption data. As a result, the dietary exposures were considered to be safe comparing to the health-based guidance values. In the case of lead, the margin of exposure (MOE) approach was applied. The MOEs calculated using the UB concentration and mean consumption data were ranged from 3 to 1000, which indicated low concern for health risk. Moreover, in this study, the dietary exposures were estimated by the Korean MFDS and U.S. FDA methods, respectively. As a result, the assessed risks were considered to be low in both cases. Based on the results of current exposure assessments, it could be considered that the food contact plastic materials are properly controlled by the regulatory authorities.


Assuntos
Acetaldeído/análise , Butileno Glicóis/análise , Exposição Dietética , Contaminação de Alimentos/análise , Chumbo/análise , Ácidos Ftálicos/análise , Ácido Acético/química , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos/instrumentação , Heptanos/química , Humanos , Plásticos/química , República da Coreia , Água/química
7.
Microb Cell Fact ; 20(1): 63, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750397

RESUMO

BACKGROUND: The alcohol 2,3-butanediol (2,3-BDO) is an important chemical and an Escherichia coli producer strain was recently engineered for bio-based production of 2,3-BDO. However, further improvements are required for realistic applications. RESULTS: Here we report that enforced ATP wasting, implemented by overexpressing the genes of the ATP-hydrolyzing F1-part of the ATPase, leads to significant increases of yield and especially of productivity of 2,3-BDO synthesis in an E. coli producer strain under various cultivation conditions. We studied aerobic and microaerobic conditions as well as growth-coupled and growth-decoupled production scenarios. In all these cases, the specific substrate uptake and 2,3-BDO synthesis rate (up to sixfold and tenfold higher, respectively) were markedly improved in the ATPase strain compared to a control strain. However, aerobic conditions generally enable higher productivities only with reduced 2,3-BDO yields while high product yields under microaerobic conditions are accompanied with low productivities. Based on these findings we finally designed and validated a three-stage process for optimal conversion of glucose to 2,3-BDO, which enables a high productivity in combination with relatively high yield. The ATPase strain showed again superior performance and finished the process twice as fast as the control strain and with higher 2,3-BDO yield. CONCLUSIONS: Our results demonstrate the high potential of enforced ATP wasting as a generic metabolic engineering strategy and we expect more applications to come in the future.


Assuntos
Trifosfato de Adenosina/metabolismo , Butileno Glicóis/análise , Butileno Glicóis/metabolismo , Escherichia coli/metabolismo , Engenharia Metabólica/métodos , Fermentação
8.
J Chromatogr Sci ; 59(2): 112-119, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33290539

RESUMO

A new, simple and stability-indicating gas chromatography-flame ionization detection (GC-FID) method was developed and validated for the quantitative determination of busulfan and its organic impurities (OI) in drug substance without derivatization. The chromatographic attributes were achieved on a fused silica capillary column (0.53 mm × 30 m, 1.0 µm, USP Phase G42), using hydrogen as a carrier gas with a split ratio of 1:1. Forced degradation studies were conducted to establish the stability-indicating capability and method specificity that showed the stressed busulfan peak was free from any co-elution. Robustness study demonstrated the chromatograms remained mostly unaffected under deliberate, but small variations of chromatographic parameters, establishing the reliability of the method during routine usage. The method was shown to be reliable, sensitive, specific, linear, accurate, precise and rugged in the 1,4-butanediol concentration range of 1-20 µg/mL. The method, intended for compendial uses, is suitable for quantitative analysis of busulfan and its organic impurities in drug substances.


Assuntos
Bussulfano/análise , Bussulfano/química , Cromatografia Gasosa/métodos , Butileno Glicóis/análise , Butileno Glicóis/química , Contaminação de Medicamentos , Estabilidade de Medicamentos , Ionização de Chama , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Food Res Int ; 123: 612-622, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31285010

RESUMO

The purpose of this study was to investigate the aroma release and perception from white bread during oral processing by gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic sensory evaluation of temporal dominance of sensations (TDS). TDS curves indicated that two maximum aroma perception signals, fermentation-like and flour-like attributes, were perceived at the beginning and swallowing, respectively. The fermentation-like, flour-like, and sour attributes were the 3 dominant aromas during oral processing. A total of 35 volatile compounds were detected in the mouth cavity during chewing white bread, 19 of them were confirmed and quantified by using the respective external standard. Based on PLSR analysis, 8 aroma compounds were predicted as potent odorants contributing to the aroma perception from chewing white bread. By application of odor activity values analysis and addition experiments, ethyl butanoate, butyl acetate, hexanal, 3-(methylthio)-propanal, 3-methylbutanal, and 2,3-butanedione were confirmed as the key odorants contributing to the aroma perception during chewing of white bread.


Assuntos
Pão/análise , Cromatografia Gasosa-Espectrometria de Massas , Mastigação , Odorantes/análise , Paladar , Acetatos/análise , Adulto , Aldeídos/análise , Butileno Glicóis/análise , Comportamento do Consumidor , Feminino , Fermentação , Farinha/análise , Humanos , Espectrometria de Mobilidade Iônica , Masculino , Pirazinas/análise , Triticum/química , Compostos Orgânicos Voláteis/análise , Adulto Jovem
10.
J Chromatogr A ; 1601: 214-223, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31076224

RESUMO

An ultra performance liquid chromatography electrospray ionization high-resolution mass spectrometry (UPLC/ESI-HRMS) method was developed and validated for simultaneous quantification of cyanogenic glycosides (CGs), [linustatin (LIS) and neolinustatin (NLIS)], and the main lignan, secoisolariciresinol diglucoside (SDG) in Linoforce® (LF) [flaxseed (Linum usitatissimum L.) coated with two herbal extracts (Senna alexandrina mill and Frangula alnus)]. CGs and SDG were extracted from defatted ground LF by a new procedure consisting of an aqueous methanol ultrasound-assisted extraction followed by an aqueous alkaline ultrasound-assisted extraction of the residue. The combined extracted solutions were then hydrolyzed by 0.02 M NaOH to release SDG from its hydroxymethyl glutaryl ester-linked complex (SDG-HMG). After hydrolysis, the sample was acidified and analyzed directly, without the need of any additional clean-up steps, by UPLC/ESI-HRMS in positive mode. The identification of CGs and SDG was confirmed by the similar retention time and similar MS spectra to the corresponding authentic standards. The quantification was performed using the corresponding extracted ion chromatograms and amygdalin as internal standard. The overall method was validated in terms of linearity, stability, selectivity, precision and accuracy. The developed method was successfully applied to the quantification of CGs and SDG in LF and also in non-coated flaxseed. This is the first report on the simultaneous quantification of CGs and SDG in LF and flaxseed.


Assuntos
Butileno Glicóis/análise , Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão , Linho/química , Glucosídeos/análise , Glicosídeos/análise , Espectrometria de Massas , Amigdalina/análogos & derivados , Amigdalina/análise , Hidrólise , Lignanas/análise , Sementes/química
11.
J Photochem Photobiol B ; 187: 141-150, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30145465

RESUMO

The multipurpose plant species Linum usitatissimum famous for producing linen fibre and containing valuable pharmacologically active polyphenols, has rarely been tested for it's in vitro biosynthesis potential of lignans and neolignans. The current study aims at the synergistic effects of mineral nutrients variation and different photoperiod treatments on growth kinetics and biomass accumulation in in vitro cultures of Linum usitatissimum. Both nutrient quality and quantity affected growth patterns, as cultures established on Gamborg B5 medium had comparatively long exponential phase compared to Murashige and Skoog medium, while growth was slow but steady until last phases of the culture on Schenk and Hildebrandt medium. Similarly, we observed that boron deficiency and nitrogen limitation in culture medium (Gamborg B5 medium) enhanced callus biomass (fresh weight 413 g/l and dry weight 20.7 g/l), phenolics production (667.60 mg/l), and lignan content (secoisolariciresinol diglucoside 6.33 and lariciresinol diglucoside 5.22 mg/g dry weight respectively) at 16/8 h light and dark-week 4, while that of neolignans (dehydrodiconiferyl alcohol glucoside 44.42 and guaiacylglycerol-ß-coniferyl alcohol ether glucoside 9.26 mg/g dry weight, respectively) in continuous dark after 4th week of culture. Conversely, maximum flavonoids production occurred at both Murashige and Skoog, Schenk and Hildebrandt media (both media types contain comparatively higher boron and nitrogen content) in the presence of continuous light. Generally, continuous dark had no significant role in any growth associated parameter. This study opens new dimension for optimizing growing conditions and evaluating underlying mechanisms in biosynthesis of lignans and neolignans in in vitro cultures of Linum usitatissimum.


Assuntos
Boro/metabolismo , Linho/metabolismo , Lignanas/biossíntese , Nitrogênio/metabolismo , Biomassa , Boro/química , Butileno Glicóis/análise , Butileno Glicóis/química , Butileno Glicóis/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/metabolismo , Linho/crescimento & desenvolvimento , Sequestradores de Radicais Livres/química , Glucosídeos/análise , Glucosídeos/química , Glucosídeos/metabolismo , Cinética , Luz , Nitrogênio/química , Fenóis/metabolismo
12.
J Chromatogr A ; 1568: 22-28, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30122165

RESUMO

A sensitive LC-MS/MS method was established to quantify diols and glycerol in fermentation broth using trichloroacetyl isocyanate as instantaneous derivatization reagent for monitoring the production of 1,3-propanediol and 2,3-butanediol from the biodiesel biorefinery process. Due to the derivatization reaction was very quickly at room temperature, only 1 min was needed for the reaction process. In addition, both extraction of analytes and evaporation of water were not employed in the analytical procedure. Furthermore, the isotope of chlorine was beneficial for understanding of the secondary mass spectrum and avoiding false positive results. Therefore, much more accurate results of diols and glycerol concentration in fermentation could be obtained even at very low levels for the evaluation of microbial metabolism pathway modification.


Assuntos
Álcoois/análise , Técnicas de Química Analítica/métodos , Cromatografia Líquida , Fermentação , Glicerol/análise , Isocianatos/química , Espectrometria de Massas em Tandem , Biocombustíveis , Butileno Glicóis/análise , Propilenoglicóis/análise
13.
Prep Biochem Biotechnol ; 48(3): 218-225, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29528267

RESUMO

Sodium percarbonate (SP), a kind of alkaline strong oxidant, was applied to corncob pretreatment. The optimized pretreatment conditions were at 4% (w/v) SP concentration with solid-to-liquid (SLR) ratio of 1:10 treating for 4 hr at 60°C. This pretreatment resulted in 91.06% of cellulose and 84.08% of hemicellulose recoveries with 34.09% of lignin removal in corncob. The reducing sugar yield from SP-pretreated corncob was 0.56 g/g after 72 hr of enzymatic hydrolysis, 1.75-folds higher than that from raw corncob. 2,3-butanediol production by Enterobacer cloacae in simultaneous saccharification fermentation was 29.18 g/L using SP-pretreated corncob as a substrate, which was 11.12 times of that using raw corncob. Scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectra analysis indicated that physical characteristics, crystallinity, and structure of corncob had changed obviously after SP pretreatment. This simple and novel pretreatment method was effective for delignification and carbohydrate retention in microbial production of 2,3-butanediol from lignocellulose biomass.


Assuntos
Biocombustíveis , Butileno Glicóis/metabolismo , Carbonatos/metabolismo , Enterobacter cloacae/metabolismo , Microbiologia Industrial/métodos , Zea mays/metabolismo , Biocombustíveis/análise , Biocombustíveis/microbiologia , Butileno Glicóis/análise , Celulose/metabolismo , Fermentação , Hidrólise , Lignina/metabolismo , Polissacarídeos/metabolismo
14.
J Food Sci ; 83(2): 300-308, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29350755

RESUMO

Flaxseed is an oilseed with many health benefits. Flaxseed may be consumed raw or in processed form. In the raw form, there is a potential for microbial contamination. Several pasteurization methods have been used to reduce microbial contamination. However, such treatments may affect chemical properties of foods. In this study, vacuum steam-pasteurization was conducted on whole flaxseed and milled flaxseed using 4 different conditions (3 min at 75 °C, 3 min at 90 °C, 9 min at 90 °C, and 3 min at 105 °C). Microbial and chemical shelf-life was monitored for 28 wk (36 wk for aerobic plate counts). Significant reduction (P < 0.05) in microbial counts (total aerobic plate counts, and yeast and mold counts) occurred after pasteurization and during storage of both whole flaxseed and milled flaxseed. Although both the moisture content and aw increased after pasteurization, they were similar to the unpasteurized samples during storage. Peroxide value, free fatty acid, headspace volatiles, fatty acid profiles, oil content, and secoisolariciresinol diglucoside (SDG) content were chemical indices measured. Only small changes were observed in the chemical indices after vacuum steam-pasteurization for both pasteurized whole flaxseed and milled flaxseed as compared to the unpasteurized flaxseed at most instances. Vacuum steam-pasteurization can be used as a safe alternative for the microbial reduction of low-moisture products, such as flaxseed, without significantly affecting chemical stability. PRACTICAL APPLICATION: Vacuum steam-pasteurization can be effectively used for the treatment of whole flaxseed and milled flaxseed to reduce spoilage microorganisms, such as total aerobes and yeasts and molds. In addition, this pasteurization method had minimal effects on several chemical shelf-life parameters with positive impact on SDG of the processed flaxseed.


Assuntos
Linho/microbiologia , Contaminação de Alimentos/análise , Manipulação de Alimentos , Microbiologia de Alimentos , Pasteurização , Butileno Glicóis/análise , Contagem de Colônia Microbiana , Ácidos Graxos/análise , Glucosídeos/análise , Peróxidos/análise , Vapor , Vácuo , Compostos Orgânicos Voláteis/análise , Água/análise
15.
J Forensic Sci ; 63(1): 326-329, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28425102

RESUMO

We report a case of fatal intoxication from 1,4-butanediol (1,4-BD), which was ingested by a young and "naïve" gamma-hydroxybutyrate (GHB) consumer during a party with the co-ingestion of alcohol, cannabis, and methylene-dioxy-methamphetamine. The following drug concentrations were found using gas chromatography coupled with mass spectrometry on autopsy samples and on a cup and a glass found at the scene: 20,350 mg/L (bottle) for 1,4-BD; 1020 mg/L (femoral blood), 3380 mg/L (cardiac blood), 47,280 mg/L (gastric content), and 570 mg/L (vitreous humor) for GHB. The concentration of GHB is difficult to interpret in forensic cases due to the possibility of an endogenous production of GHB. The variable tolerance of the user may also modify the peri- and postmortem GHB concentrations. This case underscores the need to have many different sources of toxicology samples analyzed to avoid the hypothesis of endogenous production of GHB.


Assuntos
Butileno Glicóis/intoxicação , Overdose de Drogas , Oxibato de Sódio/intoxicação , Adulto , Butileno Glicóis/análise , Depressores do Sistema Nervoso Central/análise , Dronabinol/análise , Etanol/análise , Cromatografia Gasosa-Espectrometria de Massas , Conteúdo Gastrointestinal/química , Humanos , Masculino , N-Metil-3,4-Metilenodioxianfetamina/análise , Oxibato de Sódio/análise , Corpo Vítreo/química
16.
Nat Prod Res ; 32(15): 1867-1871, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29156979

RESUMO

Hairy root culture is a promising alternative method for the production of secondary metabolites. In this study, transformed root of Linum usitatissimum was established using Agrobacterium rhizogenes A4 strain from root cultures for lignans, phenolic acids and antioxidant capacity determination. Total lignin content (secoisolariciresinol diglucoside, secoisolariciresinol and matairesinol) was 55.5% higher in transformed root cultures than in the non-transformed root culture. Secoisolariciresinol was detected in higher concentration (2.107 µmol/g DM) in the transformed root culture than non-transformed culture (1.099 µmol/g DM). Secoisolariciresinol diglucoside and matairesinol were exclusively detected in the transformed root culture, but were not found in the non-transformed root culture. The overall production of phenolic acids in transformed roots was approximately 3.5 times higher than that of the corresponding non-transformed culture. Free radical scavenging DPPH˙ and ABTS˙+ assays showed 2.9-fold and 1.76-fold higher anti-oxidant activity in transformed root culture as compared to non-transformed.


Assuntos
Antioxidantes/análise , Linho/química , Hidroxibenzoatos/análise , Lignanas/análise , Raízes de Plantas/citologia , Antioxidantes/metabolismo , Compostos de Bifenilo/metabolismo , Butileno Glicóis/análise , Linho/citologia , Furanos/análise , Glucosídeos/análise , Lignanas/química , Picratos/metabolismo , Raízes de Plantas/química , Técnicas de Cultura de Tecidos
17.
J Agric Food Chem ; 65(26): 5421-5426, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28598609

RESUMO

The aim of this work is to evaluate the possibility of using 2D-NMR for the construction of classification models for balsamic vinegars of Modena. The goal was to obtain an indirect indicator of authenticity and a quality control tool. The spectral data were analyzed by chemometric methods, aiming to discriminate the samples in relation to their origin. Application of general discriminant analysis (GDA) revealed a good discrimination; the two obtained models explained 83.9% and 97.3% of the total variance with a predictive capacity of 98.6% and 98.4%, respectively. The signals of 5-HMF, ß-glucose, 2,3-butanediol, 6-acetyl glucose, and different aliphatic signals of sugars were the most significant variables. These results are very promising for giving an important contribution in quality control and characterization of such very valuable foods.


Assuntos
Ácido Acético/química , Espectroscopia de Ressonância Magnética/métodos , Butileno Glicóis/análise , Análise Discriminante , Glucose/análise , Monossacarídeos/análise , Controle de Qualidade
18.
Molecules ; 22(5)2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28486419

RESUMO

Chocolate production suffered a vast impact with the emergence of the "witches' broom" disease in cocoa plants. To recover cocoa production, many disease-resistant hybrid plants have been developed. However, some different cocoa hybrids produce cocoa beans that generate chocolate with variable quality. Fermentation of cocoa beans is a microbiological process that can be applied for the production of chocolate flavor precursors, leading to overcoming the problem of variable chocolate quality. The aim of this work was to use a cocktail of microorganisms as a starter culture on the fermentation of the ripe cocoa pods from PH15 cocoa hybrid, and evaluate its influence on the microbial communities present on the fermentative process on the compounds involved during the fermentation, and to perform the chocolate sensorial characterization. According to the results obtained, different volatile compounds were identified in fermented beans and in the chocolate produced. Bitterness was the dominant taste found in non-inoculated chocolate, while chocolate made with inoculated beans showed bitter, sweet, and cocoa tastes. 2,3-Butanediol and 2,3-dimethylpyrazine were considered as volatile compounds making the difference on the flavor of both chocolates. Saccharomyces cerevisiae UFLA CCMA 0200, Lactobacillus plantarum CCMA 0238, and Acetobacter pasteurianus CCMA 0241 are proposed as starter cultures for cocoa fermentation.


Assuntos
Acetobacter/metabolismo , Cacau/metabolismo , Chocolate/análise , Aromatizantes/análise , Lactobacillus plantarum/metabolismo , Saccharomyces cerevisiae/metabolismo , Butileno Glicóis/análise , Cacau/genética , Quimera , Resistência à Doença/genética , Fermentação , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Pirazinas/análise , Paladar/fisiologia , Compostos Orgânicos Voláteis/análise
19.
Clin Exp Immunol ; 188(3): 371-379, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28194750

RESUMO

Small molecule metabolites that are produced or altered by host-associated microbial communities are emerging as significant immune response modifiers. However, there is a key gap in our knowledge of how oral microbial metabolites affect the immune response. Here, we examined the effects of metabolites from five bacterial strains found commonly in the oral/airway microbial communities of humans. The five strains, each isolated from cystic fibrosis patient sputum, were Pseudomonas aeruginosa FLR01 non-mucoid (P1) and FLR02 mucoid (P2) forms, Streptococcus pneumoniae (Sp), S. salivarius (Ss) and Rothia mucilaginosa (Rm). The effect of bacterial metabolites on dendritic cell (DC) activation, T cell priming and cytokine secretion was determined by exposing DCs to bacterial supernatants and individual metabolites of interest. Supernatants from P1 and P2 induced high levels of tumour necrosis factor (TNF)-α, interleukin (IL)-12 and IL-6 from DCs and primed T cells to secrete interferon (IFN)-γ, IL-22 compared to supernatants from Sp, Ss and Rm. Investigations into the composition of supernatants using gas chromatography-mass spectroscopy (GC-MS) revealed signature metabolites for each of the strains. Supernatants from P1 and P2 contained high levels of putrescine and glucose, while Sp and Ss contained high levels of 2,3-butanediol. The individual metabolites replicated the results of whole supernatants, although the magnitudes of their effects were reduced significantly. Altogether, our data demonstrate for the first time that the signature metabolites produced by different bacteria have different effects on DC functions. The identification of signature metabolites and their effects on the host immune system can provide mechanistic insights into diseases and may also be developed as biomarkers.


Assuntos
Bactérias/metabolismo , Células Dendríticas/imunologia , Microbiota , Sistema Respiratório/microbiologia , Células Th1/imunologia , Butileno Glicóis/análise , Diferenciação Celular , Células Cultivadas , Fibrose Cística/microbiologia , Citocinas/metabolismo , Células Dendríticas/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ativação Linfocitária , Escarro/microbiologia
20.
Food Chem ; 214: 227-233, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27507470

RESUMO

Flaxseed (Linum usitatissimum L.) is a rich source of nutritive and bioactive compounds. The research evaluated the disparity in phytochemical profiles along with total and cellular antioxidant activities between oil and fiber flaxseeds. There were significant differences in total phenolics, total flavonoids and antioxidant activities among the six cultivars of fiber and oil flaxseed, respectively. Four phytochemical compounds including caffeic acid, p-coumaric acid and ferulic acid, and secoisolariciresinol diglucoside (SDG) were identified and quantified in the cultivars of oil and fiber flaxseed by HPLC analysis. Notably, the average of total phenolic and flavonoid contents, along with total antioxidant activities between fiber and oil flaxseeds were not different significantly; even the cellular antioxidant activity of fiber flaxseed was superior to oil flaxseed. These results suggest that fiber flaxseeds would be valuable candidates as functional products and dietary supplements production owing to the higher bioactive values as well as oil flaxseeds.


Assuntos
Fibras na Dieta/análise , Linho/química , Óleo de Semente do Linho/química , Compostos Fitoquímicos/análise , Sementes/química , Butileno Glicóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/análise , Flavonoides/análise , Glucosídeos/análise , Fenóis/análise , Propionatos
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