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1.
Food Chem X ; 21: 101114, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38298354

RESUMO

Two new -biotics concepts, such as paraprobiotics and postbiotics were introduced, with beneficial effects beyond the viability of probiotic. In this study, the effect of individual (thermal, ohmic heating, high pressure, and ultrasound) and combined (ohmic, high pressure and ultrasound in combination with heating) treatments on the inactivation kinetics of Lactiplantibacillus plantarum was investigated. Different inactivation rates were obtained, up to 8.18 after 10 min at 90 °C, 2.07 after 15 min at a voltage gradient of 20 V/cm, 6.62 after 10 min at 600 MPa and 3.6 after ultrasound treatment for 10 min at 100 % amplitude. The experimental data were fitted to Weibullian model proposed by Peleg, allowing to estimate the inactivation rate coefficient (b) and the shape of the inactivation curves (n). At lower concentration, the samples showed both cytocompatibility and antiproliferative effect, stimulating the cell proliferation on both murine fibroblast and human colorectal adenocarcinoma cell lines.

2.
Foods ; 12(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37835241

RESUMO

Conjugation of the proteins with carbohydrates, occurring in the early stages of the Maillard reactions, received increased attention because of the high potential to ensure the improvement of the biological activity and functional properties of the proteins of different origins. The Maillard conjugates are conventionally formed through wet or dry heating, but the use of alternative technologies involving ultrasound, microwave, pulsed electric fields, high-pressure, or electrodynamic treatments appears to be efficient in accelerating the reaction steps and limiting the formation of toxic compounds. An overview of the mechanisms of these processing technologies, the main parameters influencing the Maillard conjugate formation, as well as their advantages and disadvantages, is provided in this paper. Different strategies employing these alternative technologies are reported in the literature: as pretreatment of the proteins, either alone or in admixture with the carbohydrates, followed by conventional heating, as a single alternative treatment step, or as a combination of heating and alternative processing. The desired functional properties of the proteins can be achieved by selecting the appropriate processing strategy and optimizing the reaction parameters. Moreover, alternative technologies can be exploited to obtain Maillard conjugates with remarkable biological activity in terms of antioxidant, antimicrobial, antihypertensive, anti-inflammatory, antimutagenic, or bifidogenic properties.

3.
Foods ; 12(13)2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37444320

RESUMO

Wild artisanal cultures, such as a symbiotic culture of bacteria and yeasts (SCOBY) and water kefir grains (WKG), represent a complex microorganism consortia that is composed of yeasts and lactic and acetic acid bacteria, with large strains of diversity and abundance. The fermented products (FPs) obtained by the microbiome's contribution can be included in functional products due to their meta-biotics (pre-, pro-, post-, and paraprobiotics) as a result of complex and synergistic associations as well as due to the metabolic functionality. In this study, consortia of both SCOBY and WKG were involved in the co-fermentation of a newly formulated substrate that was further analysed, aiming at increasing the postbiotic composition of the FPs. Plackett-Burman (PBD) and Response Surface Methodology (RSM) techniques were employed for the experimental designs to select and optimise several parameters that have an influence on the lyophilised starter cultures of SCOBY and WKG activity as a multiple inoculum. Tea concentration (1-3%), sugar concentration (5-10%), raisins concentration (3-6%), SCOBY lyophilised culture concentration (0.2-0.5%), WKG lyophilised culture concentration (0.2-0.5%), and fermentation time (5-7 days) were considered the independent variables for mathematical analysis and fermentation conditions' optimisation. Antimicrobial activity against Bacillus subtilis MIUG B1, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Aspergillus niger MIUG M5, antioxidant capacity (DPPH), pH and the total acidity (TA) were evaluated as responses. The rich postbiotic bioactive composition of the FP obtained in optimised biotechnological conditions highlighted the usefulness of the artisanal co-cultures, through their symbiotic metabolic interactions for the improvement of bioactive potential.

4.
J Food Prot ; 86(1): 100026, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36916585

RESUMO

This study assessed the growth of Listeria monocytogenes in ready-to-eat (RTE) ham during storage under conditions simulating domestic practices with the intention to offer support in the elaboration of food safety policies that should better protect consumers against food poisoning at home. RTE ham, artificially contaminated at either medium (102-103 CFU/g) or high (104-105 CFU/g) concentration, was stored at both isothermal (4℃ in a refrigerator able to maintain a relatively constant temperature and 5℃ and 7℃ in a refrigerator with fluctuating temperature) and dynamic (5℃ and 7℃ with intermittent exposure to ambient temperature, e.g. 25℃) conditions. Under isothermal conditions, the increasing storage temperature determined a significantly increased (p < 0.05) capacity of L. monocytogenes to grow. The kinetic growth parameters were derived by fitting the Baranyi and Roberts model to the experimental data and, based on the maximum specific growth rates, it was estimated the temperature dependence of L. monocytogenes growth in RTE ham. At medium contamination level, sanitary risk time calculation revealed that, unlike storage at 5℃ and 7℃, storage at 4℃ of the RTE ham extends the time period during which the product is safe for consumption by ∼40 and 52%, respectively. However, the real temperature fluctuations included in the Monte Carlo simulations at low L. monocytogenes counts (1, 5 and 10 CFU/g) have shortened the safety margins. Stochastic models also proved to be useful tools for describing the pathogen's behavior when refrigeration of the RTE ham alternates with periods of ham being kept at room temperature, considered dynamic conditions of growth.


Assuntos
Listeria monocytogenes , Produtos da Carne , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Método de Monte Carlo , Temperatura , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor
5.
Rev. CES psicol ; 15(3): 115-132, sep.-dic. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1406721

RESUMO

Resumen El consumo de sustancias psicoactivas [SPA] es un problema de salud pública, y constituye uno de los principales factores de riesgo para la salud. Se ha observado que el consumo de SPA está mediado por diferentes variables, una de ellas es la desregulación emocional, y se requiere mayor investigación del comportamiento de esta variable y su relación con los niveles de riesgo asociado al consumo. El objetivo del presente estudio fue determinar si existen diferencias en la desregulación emocional según el nivel de riesgo asociado al consumo de sustancias en una muestra de universitarios. Para tal efecto se adelantó un estudio descriptivo por comparación de grupos con una muestra de 721 estudiantes. Los resultados indicaron altas prevalencias de consumo de SPA; diferencias en los puntajes de desregulación emocional según el nivel de riesgo para tranquilizantes y cocaína, y que, a nivel general, aquellos universitarios con menor nivel de riesgo son quienes presentan menores puntajes de desregulación emocional, lo que sugiere que la desregulación emocional es una variable predictora de un mayor nivel de riesgo asociado al consumo de SPA.


Abstract The use of psychoactive substances is a public health problem, and it is one of the main health risk factors. It has been observed that the use of drugs is mediated by different variables, one of them is the emotional dysregulation, and more research is required on the behavior of this variable and its relationship with the levels of risk in the consumption. The aim of this study was to determine whether there are differences in emotional dysregulation according to the level of risk associated with substance use in a sample of 721 university students. For this purpose, a descriptive study was carried out by comparing groups. The results indicated high prevalence of PAS consumption, differences in emotional dysregulation scores according to the risk level for tranquilizer pills and cocaine. In general, the students with a lower risk level are those who present lower emotional dysregulation scores, suggesting that emotional dysregulation is a predictor variable of a higher level of risk associated with PAS consumption.

6.
Membranes (Basel) ; 12(3)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35323801

RESUMO

Edible coatings are important for horticulture crops preservation and reducing food waste. Application of edible coatings followed by low-temperature storage prolongs the storability, preserves quality, and decreases the overall postharvest losses. This study evaluated the efficacy of two nanoemulsions formulae containing thyme essential oil and whey proteins as coatings for zucchini, with the purpose of extending their shelf-life. The nanoemulsions were rheologically evaluated and the formula with guar and arabic gum mix stabilizer (S) showed a better capacity to restructure after strain compared to the formulae with Tween 20 (T). The S coating material had a better capacity to integrate nanoparticles compared to T. However, when applied on zucchini, T coating was more effective in reducing weight loss showing 16% weight loss compared to 21% in S, after 42 days. At the end of storage at 10 °C, the T-coated zucchini had better firmness (p < 0.05) compared with S and both coatings were superior to control (p < 0.05). POD (peroxidase) activity was high in peel at the end of storage when also CAT (catalase) showed a sudden increase. On the 42nd day of storage, the highest enzymes activity (CAT, POD, and APX (ascorbate peroxidase)) was present in the S-coated zucchini peel. The most abundant volatile in T coating was α-pinene and 4-carene in S. Sensory analysis showed that T coating delayed the appearance of senescence while S exhibited surface cracks.

7.
Food Control ; 131: 108433, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34980942

RESUMO

Our paper emphasizes the importance of the kitchen layout in facilitating consumers' food hygiene practices. A significant correlation was found between the sink placement (inside or outside the kitchen) and hygienic practices during food handling based on a survey performed on consumers from ten European countries, indicating that those who had the sink in the kitchen were more likely to perform proper hygiene practices than those who have not. The self-reported practices were supported by observed practices in 64 households from five European countries. The observational study combined with the examination of kitchen layouts revealed that the kitchen work triangle with its apexes represented by the kitchen sink, cooking stove and refrigerator, which is recommended for ergonomic reasons by architects and designers, did not necessarily support food hygiene practices in kitchens. Cross-contamination events were associated with the sink - countertop distances longer than 1 m. Based on this, a new kitchen triangle with its apexes represented by the kitchen sink, working place (usually countertop) and cooking stove, with the distance between the sink and the working place less than 1 m is proposed to be used as norm in kitchen designs for combining ergonomics with safety. This triangle is proposedly named the food safety triangle and is aimed to mitigate the risks of foodborne illnesses by creating an arrangement that facilitates hygiene practices. This study is the first to highlight the importance of implementing the concept of food safety in the kitchen design based on significant correlations between kitchen equipment placement and consumers' food safety practices.

8.
Foods ; 10(11)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34828860

RESUMO

A bottom-up approach identifying equivalent effects of high-pressure processing (HPP-600 MPa, 20 °C, 10 min), thermal treatment (TT-70 °C, 15 min) and high pressure-mild thermal processing (HPMT-600 MPa, 50 °C, 10 min) on quality and stability of peach-strawberry puree was applied during refrigerated storage. TT and HPP ensured 3-log aerobic bacteria inactivation at first, while HPMT reduction was below the detection limit. After 21 days all samples had equivalent microbiological stability. A 2.6-fold increase in the residual activity of PPO and POD was found in the HPP sample compared to TT and HPMT samples (1st day); after 21 days PPO, POD and TPC were equivalent for TT and HPP peach-strawberry purees. Equivalent volatile profile and rheology behavior was observed after 21 days of all samples' storage. Meanwhile, the color of the HPP, TT and HMPT samples remained significantly different (p < 0.05) throughout the whole storage period, with the lowest browning index registered for HPP samples.

9.
Data Brief ; 38: 107362, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34568525

RESUMO

The data presented here capture the structure of kitchen layouts belonging to consumers vulnerable to foodborne diseases and food risk-takers. Data were collected in the frame of the SafeConsume project by multidisciplinary research teams that visited consumers during preparing a meal and had the possibility to examine their cooking routines. Distances between sink and stove, sink and refrigerator, stove and refrigerator, sink and working place (countertop or table), stove and working place were analyzed to correlate food safety practices applied during cooking with kitchen arrangements. The results arising from analyzing the ergonomics of kitchens versus potential cross-contamination events are presented in Mihalache et al., [1]. These data contribute to a better understanding of real kitchen layouts and can be used as a starting point for future research regarding food safety-oriented arrangements instead of ergonomics-focused designs, for food safety risk assessments, as study cases for explaining specific measures that can be established to improve food handling and hygiene practices in homes and for sociological research pointing consumers' behavior during cooking.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34444577

RESUMO

The objective of this study was to evaluate the efficacy of dirt removal (bacteria and organic matter) of several hand-cleaning procedures. The results from the hand hygiene experiment indicated that washing hands with warm water and soap for 20 s is the most effective method investigated when hands are either dirty or greasy. Even if not proper washing, rinsing under running water for 5 s is a cleaning procedure that may significantly reduce the probability of cross-contamination, as it removes 90% of the hands' dirt. Although less effective than water and soap, the usage of antibacterial wipes was significantly more effective than wet wipes, indicating that they are a better choice when water and soap are not available. The results of this study enable us to inform consumers about the effectiveness of hand-cleaning procedures applied in their homes when cooking. Moreover, it can make consumers understand why, during the COVID-19 pandemic, authorities recommended washing hands as a preventive measure of infection and using an anti-bacterial hand gel or wiping hands with an antimicrobial wipe if water and soap are not available.


Assuntos
COVID-19 , Higiene das Mãos , Bactérias , Contagem de Colônia Microbiana , Culinária , Mãos , Desinfecção das Mãos , Humanos , Medições Luminescentes , Pandemias , SARS-CoV-2 , Sabões
11.
Compr Rev Food Sci Food Saf ; 20(3): 2716-2741, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33960652

RESUMO

Nontyphoidal salmonellae are among the most prevalent foodborne pathogens causing gastrointestinal infections worldwide. A high number of cases and outbreaks of salmonellosis are associated with the consumption of eggs and egg products, and several of these occur at the household level. The aim of the current study is to critically evaluate the current status of knowledge on Salmonella in eggs from a consumer's perspective, analyzing the hazard occurrence and the good practices that should be applied to reduce salmonellosis risk. Following a HACCP (Hazard Analysis and Critical Control Point) based approach, some steps along the food journey were identified as Critical Consumer Handling (CCH)-steps in which consumers, through their behavior or choice, can significantly reduce the level of Salmonella in eggs and egg products. From shopping/collecting to consumption, each of these steps is discussed in this review to provide an evidence-based overview of risk factors of human salmonellosis related to egg consumption. The main message to consumers is to choose Salmonella-free eggs (those that some official entity or producer guarantees that does not contain Salmonella), when available, especially for dishes that are not fully heat treated. Second, as guaranteed Salmonella-free eggs are only available in a few countries, refrigerated storage from the point of collection and proper cooking will significantly reduce the risk of salmonellosis. This will require a revision of the actual recommendations/regulations, as not all ensure that eggs are maintained at temperatures that prevent growth of Salmonella from collection until the time of purchasing.


Assuntos
Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Ovos , Humanos , Fatores de Risco , Salmonella , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia
12.
BMC Genomics ; 22(1): 266, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853520

RESUMO

BACKGROUND: The pathogen Listeria (L.) monocytogenes is known to survive heat, cold, high pressure, and other extreme conditions. Although the response of this pathogen to pH, osmotic, temperature, and oxidative stress has been studied extensively, its reaction to the stress produced by high pressure processing HPP (which is a preservation method in the food industry), and the activated gene regulatory network (GRN) in response to this stress is still largely unknown. RESULTS: We used RNA sequencing transcriptome data of L. monocytogenes (ScottA) treated at 400 MPa and 8∘C, for 8 min and combined it with current information in the literature to create a transcriptional regulation database, depicting the relationship between transcription factors (TFs) and their target genes (TGs) in L. monocytogenes. We then applied network component analysis (NCA), a matrix decomposition method, to reconstruct the activities of the TFs over time. According to our findings, L. monocytogenes responded to the stress applied during HPP by three statistically different gene regulation modes: survival mode during the first 10 min post-treatment, repair mode during 1 h post-treatment, and re-growth mode beyond 6 h after HPP. We identified the TFs and their TGs that were responsible for each of the modes. We developed a plausible model that could explain the regulatory mechanism that L. monocytogenes activated through the well-studied CIRCE operon via the regulator HrcA during the survival mode. CONCLUSIONS: Our findings suggest that the timely activation of TFs associated with an immediate stress response, followed by the expression of genes for repair purposes, and then re-growth and metabolism, could be a strategy of L. monocytogenes to survive and recover extreme HPP conditions. We believe that our results give a better understanding of L. monocytogenes behavior after exposure to high pressure that may lead to the design of a specific knock-out process to target the genes or mechanisms. The results can help the food industry select appropriate HPP conditions to prevent L. monocytogenes recovery during food storage.


Assuntos
Listeria monocytogenes , Listeria , Manipulação de Alimentos , Microbiologia de Alimentos , Armazenamento de Alimentos , Listeria monocytogenes/genética
13.
BMC Res Notes ; 14(1): 137, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858503

RESUMO

OBJECTIVES: The study aims to generate the whole genome sequence of L. monocytogenes strain S2542 and to compare it to the genomes of strains RO15 and ScottA. In addition, we aimed to compare gene expression profiles of L. monocytogenes strains S2542, ScottA and RO15 after high-pressure processing (HPP) using ddPCR. RESULTS: The whole genome sequence of L. monocytogenes S2542 indicates that this strain belongs to serotype 4b, in contrast to the previously reported serotype 1/2a. Strain S2542 appears to be more susceptible to the treatment at 400 MPa compared to RO15 and ScottA strains. In contrast to RO15 and ScottA strains, viable cell counts of strain S2542 were below the limit of detection after HPP (400 MPa/8 min) when stored at 8 °C for 24 and 48 h. The transcriptional response of all three strains to HPP was not significantly different.


Assuntos
Listeria monocytogenes , Microbiologia de Alimentos , Técnicas Genéticas , Listeria monocytogenes/genética
14.
Int J Food Microbiol ; 347: 109172, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33812164

RESUMO

About 40% of foodborne infections are acquired in the home. The aim of the present study was to track contamination of pathogens during domestic food preparation and link the contamination to preparation practices. Research participants from 87 households in six European countries were observed and interviewed during shopping and preparation of a chicken and vegetable meal. The presence of Salmonella spp., Campylobacter spp. and norovirus on raw chicken, kitchen surfaces, cloths and sponges was determined. The prevalence of Campylobacter on raw chicken varied from 8.3% in Norway (NO) to 80% in France (FR) and Portugal (PT), with a mean prevalence of 57%. Campylobacter was found on half of the products that had been frozen and appeared to be less prevalent on chicken from supermarkets than other sources. Salmonella was found in 8.6% of raw chicken samples, exclusively from Hungary (HU). A relationship between observed practices and spread of pathogens to kitchen surfaces was found only for the use of cutting boards for chicken and/or vegetables. After food preparation, Campylobacter and Salmonella were isolated from 23% (samples derived from HU, RO, UK) and 8.7% (HU), respectively of cutting boards. Research participants in France and Portugal were more likely to buy products that fitted their recipe, with less need for using cutting boards. Using the same board and knife for vegetables after using it for chicken and without washing with detergent was common in Portugal and Romania, but not in the other countries. Contamination with Campylobacter to other kitchen surfaces or washing utensils were found in five households (UK, RO, PT). Rinsing chicken in sinks was common in three countries (PT, HU, RO), and washing vegetables in the same sink was also usual. Prevalence of Norovirus was low, with detection in one out of 451 samples. The participants' awareness of the risk posed by pathogens from raw chicken differed among the six countries, with higher awareness in Norway and the UK than the other countries studied. In conclusion, practices intended to avoid cross-contamination from chicken to kitchen surfaces and washing utensils are not established among consumers in all European countries. Nevertheless, cross-contamination events that disseminate infectious doses of pathogens seems to be rare, probably due to the relatively low levels of pathogens in food combined with food preferences. Food safety interventions must consider the national food culture, preferences, practices and the prevalence and levels of pathogens in food. Emphasis should be on providing and promoting chicken products with lower risk (prevalence of pathogens, ready-to-cook) and safe use of cutting boards.


Assuntos
Campylobacter/isolamento & purificação , Manipulação de Alimentos , Microbiologia de Alimentos , Norovirus/isolamento & purificação , Salmonella/isolamento & purificação , Animais , Galinhas , Europa (Continente) , Características da Família , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Humanos , Aves Domésticas/microbiologia , Aves Domésticas/virologia , Prevalência , Verduras/microbiologia , Verduras/virologia
15.
BMC Genomics ; 22(1): 117, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579201

RESUMO

BACKGROUND: High-pressure processing (HPP) is a commonly used technique in the food industry to inactivate pathogens, including L. monocytogenes. It has been shown that L. monocytogenes is able to recover from HPP injuries and can start to grow again during long-term cold storage. To date, the gene expression profiling of L. monocytogenes during HPP damage recovery at cooling temperature has not been studied. In order identify key genes that play a role in recovery of the damage caused by HPP treatment, we performed RNA-sequencing (RNA-seq) for two L. monocytogenes strains (barotolerant RO15 and barosensitive ScottA) at nine selected time points (up to 48 h) after treatment with two pressure levels (200 and 400 MPa). RESULTS: The results showed that a general stress response was activated by SigB after HPP treatment. In addition, the phosphotransferase system (PTS; mostly fructose-, mannose-, galactitol-, cellobiose-, and ascorbate-specific PTS systems), protein folding, and cobalamin biosynthesis were the most upregulated genes during HPP damage recovery. We observed that cell-division-related genes (divIC, dicIVA, ftsE, and ftsX) were downregulated. By contrast, peptidoglycan-synthesis genes (murG, murC, and pbp2A) were upregulated. This indicates that cell-wall repair occurs as a part of HPP damage recovery. We also observed that prophage genes, including anti-CRISPR genes, were induced by HPP. Interestingly, a large amount of RNA-seq data (up to 85%) was mapped to Rli47, which is a non-coding RNA that is upregulated after HPP. Thus, we predicted that Rli47 plays a role in HPP damage recovery in L. monocytogenes. Moreover, gene-deletion experiments showed that amongst peptidoglycan biosynthesis genes, pbp2A mutants are more sensitive to HPP. CONCLUSIONS: We identified several genes and mechanisms that may play a role in recovery from HPP damage of L. monocytogenes. Our study contributes to new information on pathogen inactivation by HPP.


Assuntos
Listeria monocytogenes , Microbiologia de Alimentos , Indústria de Processamento de Alimentos , Listeria monocytogenes/genética , Temperatura , Transcriptoma
16.
Foods ; 9(7)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630028

RESUMO

Application of high pressure-thermal treatment (600 MPa and 70 °C, 20 min) for obtaining edible films functionalized with thyme extracts have been studied in order to evaluate the antimicrobial capacity of films structure to retain and release the bioactive compounds. The high pressure-thermally treated films (HPT) were compared with the thermally treated (TT) ones (80 ± 0.5 °C, 35 min). The film structures were analyzed and the sorption isotherms, water vapor permeability, antimicrobial activity and the volatile fingerprints by GC/MS were performed. The HPT film presented more binding sites for water chemi-sorption than TT films and displayed significantly lower WVP than TT films (p < 0.05). TT films displayed slightly, but significant higher, antimicrobial activity (p < 0.05) against Geotrichum candidum in the first day and against Bacillus subtilis in the 10th day of storage. The HPT film structure had ~1.5-fold higher capacity to retain volatiles after drying compared to TT films. From the HPT films higher amount of p-cymene and α-terpinene was volatilized during 10 days of storage at 25 °C, 50% RH while from the TT films higher amount of caryophyllene and carvacrol were released. During storage HPT films had a 2-fold lower capacity to retain monoterpenes compared to TT films.

17.
Molecules ; 25(10)2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32429231

RESUMO

Identification and quantification of polyphenols in plant material are of great interest since they make a significant contribution to its total bioactivity. In the present study, an UPLC-Orbitrap-MS/MS approach using the variable data acquisition mode (vDIA) was developed and applied for rapid separation, identification, and quantification of the main polyphenolic compounds in Medicago sativa L. and Trifolium pratense L. sprouts in different germination stages. Based on accurate MS data and fragment ions identification strategy, a total of 29 compounds were identified by comparing their accurate masses, fragment ions, retention times, and literatures. Additionally, a number of 30 compounds were quantified by comparing to the reference standards. Data were statistically analysed. For both plant species, the sprouts of the third germination day are valuable sources of bioactive compounds and could be used in phytotherapy and nutrition. Although Trifolium pratense L. (Red Clover) is considered to be a reference for natural remedies in relieving menopause disorders, alfalfa also showed a high level of biological active compounds with estrogenic activity.


Assuntos
Flavonoides/química , Medicago sativa/química , Polifenóis/química , Plântula/química , Trifolium/química , Cromatografia Líquida de Alta Pressão , Flavonoides/classificação , Flavonoides/isolamento & purificação , Germinação/fisiologia , Limite de Detecção , Espectrometria de Massas , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/metabolismo , Extratos Vegetais/química , Polifenóis/classificação , Polifenóis/isolamento & purificação , Padrões de Referência , Plântula/metabolismo , Fatores de Tempo , Trifolium/crescimento & desenvolvimento , Trifolium/metabolismo
18.
Molecules ; 25(10)2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32456245

RESUMO

Oleoresin supercritical extracts from sea buckthorn were microencapsulated in whey proteins isolate and casein, in two states: native (N) and cross-linked mediated by transglutaminase (TG). The encapsulation efficiency showed values higher than 92% for total carotenoids and lycopene. Phytochemicals content was 352.90 ± 1.02 mg/g dry weight (DW) for total carotenoids in TG and 302.98 ± 2.30 mg/g DW in N, with antioxidant activity of 703.13 ± 23.60 mMol Trolox/g DW and 608.74 ± 7.12 mMol Trolox/g DW, respectively. Both powders had an inhibitory effect on α-glucosidase, of about 40% for N and 35% for TG. The presence of spherosomes was highlighted, with sizes ranging between 15.23-73.41 µm and an agglutination tendency in N, and lower sizes, up to 35 µm in TG. The in vitro digestibility revealed a prolonged release in an intestinal environment, up to 65% for TG. Moisture sorption isotherms were studied at 20 °C and the shape of curves corresponds to sigmoidal type II model. The presence of cross-linked mediated aggregates in TG powders improved stability and flowability. Our results can be used as evidence that cross-linked aggregates mediated by transglutaminase applied for microencapsulation of oleoresins have the potential to become new delivery systems, for carotenoids and lycopene, being valuable in terms of their attractive color and biological and bioaccessibility properties.


Assuntos
Dióxido de Carbono/química , Hippophae/química , Extratos Vegetais/química , Composição de Medicamentos
19.
J Environ Sci Health B ; 55(5): 484-494, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022645

RESUMO

Given that the pesticide and fungicide residues determination in honey is not a routine analysis in Romania, information on these emerging contaminants is useful for consumer's safety. High resolution mass spectrometry technique was applied by Q-Exactive Orbitrap LC-MS/MS to identify and quantify environmental contaminants in honey. A list of 25 compounds, biocides and antifungals was selected for the method development, based on the occurrence in the Romanian environment and their potential usage in agriculture. The method was applied for 18 various honey samples collected in different geographic regions of Romania. Eleven compounds were present in the honey samples: carbendazim, enilconazole, hexaconazole, penconazole, tebuconazole, flusilazole, thiabendazole, terconazole, cyproconazole, propiconazole, metalaxyl. Targeted MS/MS analyses were performed for confirmation. The measured quantities ranged from 1.7-7.2 µg kg-1, lower than MRLs established by the legislation. The most abundant compound was enilconazole (imazalil), which was detected in fourteen samples. To the best of our knowledge, the present study is the first one concerning antifungal contamination of honey in Romania. The results proved that the tested honey samples are safe for human consumption.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Mel/análise , Praguicidas/análise , Cromatografia Líquida/métodos , Fungicidas Industriais/análise , Romênia , Espectrometria de Massas em Tandem/métodos
20.
Int Microbiol ; 23(2): 179-188, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31267375

RESUMO

This investigation was aimed to evaluate the antimicrobial activities and involvement of extracellular lytic enzymes produced by four strains of Trichoderma in the inhibition of Pythium myriotylum. Antagonistic effects were tested by dual culture. Activities of lytic enzymes were evaluated from the filtrate of each strain after cultivation in selected media. Organic extracts were obtained from liquid media subsequent to the cultivation of Trichoderma in potato dextrose broth (PDB). Non-volatile organic compounds such as polyphenols and flavonoids were evaluated spectrophotometrically while volatile organic compounds (VOCs) were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The antimicrobial activity of the organic extracts was determined using the poisoning method. Results have shown that all the strains were antagonists against P. myriotylum. T. erinaceum (IT-58), T. gamsii (IT-62), T. afroharzianum (P8), and T. harzianum (P11) that were found to produce cellulase, protease, and xylanase. Over 20 compounds were identified in each extract, including esters, lactones, and organic acids. The organic extracts also contained high amounts of polyphenolic compounds and flavonoids and significantly inhibited the mycelial growth of P. myriotylum. The minimal inhibition concentrations were 80 µg/µL, 40 µg/µL, 20 µg/µL, and 10 µg/µL, for extracts obtained from T. erinaceum (IT-58), T. gamsii (IT-62), T. afroharzianum (P8), and T. harzianum (P11), respectively. There was significant correlation between the production of total polyphenol and flavonoid content and the antagonistic effects of the tested strains.


Assuntos
Doenças das Plantas/microbiologia , Pythium/microbiologia , Trichoderma , Xanthosoma/microbiologia , Antifúngicos/química , Antifúngicos/farmacologia , Agentes de Controle Biológico , Celulase/metabolismo , Misturas Complexas/química , Misturas Complexas/farmacologia , Endo-1,4-beta-Xilanases/metabolismo , Enzimas/metabolismo , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Doenças das Plantas/prevenção & controle , Metabolismo Secundário , Trichoderma/química , Trichoderma/metabolismo , Xanthosoma/crescimento & desenvolvimento
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