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1.
Nutrients ; 16(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38931267

RESUMO

BACKGROUND: The SI.Menu study offers the latest data on the dietary intake of Slovenian adolescents aged 10 to 17. The purpose of this study is to comprehensively assess their dietary intake (energy and nutrients) and compare their food intakes with dietary recommendations for healthy and sustainable diets. METHODS: The cross-sectional epidemiological dietary study SI.Menu (March 2017-April 2018) was conducted on a representative sample of Slovenian adolescents aged 10 to 17 years (n = 468) (230 males and 238 females). Data on dietary intake were gathered through two non-consecutive 24 h recalls, in line with the European Food Safety Authority (EFSA) EU Menu methodology. The repeated 24 h Dietary Recall (HDR) and Food Propensity Questionnaire (FPQ) data were combined to determine the usual intakes of nutrients and food groups, using the Multiple Source Method (MSM) program. RESULTS: Adolescents' diets significantly deviate from dietary recommendations, lacking vegetables, milk and dairy products, nuts and seeds, legumes, and water, while containing excessive meat (especially red meat) and high-sugar foods. This results in insufficient intake of dietary fibre, and nutrients such as vitamin D, folate, and calcium. CONCLUSIONS: The dietary intake of Slovenian adolescents does not meet healthy and sustainable diet recommendations. This study provides an important insight into the dietary habits of Slovenian adolescents that could be useful for future public health strategies.


Assuntos
Dieta Saudável , Humanos , Adolescente , Feminino , Masculino , Criança , Eslovênia , Estudos Transversais , Dieta/estatística & dados numéricos , Dieta/normas , Comportamento Alimentar , Recomendações Nutricionais , Inquéritos sobre Dietas , Ingestão de Alimentos , Ingestão de Energia , Fenômenos Fisiológicos da Nutrição do Adolescente
2.
Pathog Dis ; 822024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38730561

RESUMO

Antibiotic resistance (ATBR) is increasing every year as the overuse of antibiotics (ATBs) and the lack of newly emerging antimicrobial agents lead to an efficient pathogen escape from ATBs action. This trend is alarming and the World Health Organization warned in 2021 that ATBR could become the leading cause of death worldwide by 2050. The development of novel ATBs is not fast enough considering the situation, and alternative strategies are therefore urgently required. One such alternative may be the use of non-thermal plasma (NTP), a well-established antimicrobial agent actively used in a growing number of medical fields. Despite its efficiency, NTP alone is not always sufficient to completely eliminate pathogens. However, NTP combined with ATBs is more potent and evidence has been emerging over the last few years proving this is a robust and highly effective strategy to fight resistant pathogens. This minireview summarizes experimental research addressing the potential of the NTP-ATBs combination, particularly for inhibiting planktonic and biofilm growth and treating infections in mouse models caused by methicillin-resistant Staphylococcus aureus or Pseudomonas aeruginosa. The published studies highlight this combination as a promising solution to emerging ATBR, and further research is therefore highly desirable.


Assuntos
Antibacterianos , Biofilmes , Gases em Plasma , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Gases em Plasma/farmacologia , Animais , Humanos , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Camundongos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Farmacorresistência Bacteriana , Resistência Microbiana a Medicamentos , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/tratamento farmacológico , Modelos Animais de Doenças , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/tratamento farmacológico
3.
Int J Biol Macromol ; 270(Pt 2): 132308, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38740163

RESUMO

UV-ozone activated polypropylene (PP) food films were subjected to a novel bilayer coating process involving primary or quaternary chitosan (CH/QCH) as the first layer and natural extracts from juniper needles (Juniperus oxycedrus; JUN) or blackberry leaves (Rubus fruticosus; BBL) as the second layer. This innovative approach aims to redefine active packaging (AP) development. Through a detailed analysis by surface characterization and bioactivity assessments (i.e., antioxidant and antimicrobial functionalities), we evaluated different coating combinations. Furthermore, we investigated the stability and barrier characteristics inherent in these coatings. The confirmed deposition, coupled with a comprehensive characterization of their composition and morphology, underscored the efficacy of the coatings. Our investigation included wettability assessment via contact angle (CA) measurements, X-ray photoelectron spectroscopy (XPS), and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), which revealed substantial enhancements in surface concentrations of elements and functional groups of CH, QCH, JUN, and BBL. Scanning electron microscopy (SEM) unveiled the coatings' heterogeneity, while time-of-flight secondary ion mass spectrometry (ToF-SIMS) and CA profiling showed moderately compact bilayers on PP, providing active species on the hydrophilic surface, respectively. The coatings significantly reduced the oxygen permeability. Additionally, single-layer depositions of CH and QCH remained below the overall migration limit (OML). Remarkably, the coatings exhibited robust antioxidative properties due to plant extracts and exceptional antimicrobial activity against S. aureus, attributed to QCH. These findings underscore the pivotal role of film surface properties in governing bioactive characteristics and offer a promising pathway for enhancing food packaging functionality.


Assuntos
Quitosana , Embalagem de Alimentos , Extratos Vegetais , Polipropilenos , Quitosana/química , Quitosana/farmacologia , Polipropilenos/química , Embalagem de Alimentos/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Juniperus/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Rubus/química , Propriedades de Superfície , Molhabilidade
4.
J Ethnopharmacol ; 321: 117461, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979817

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Paulownia tomentosa Steud. (P. tomentosa) is a medium-sized tree traditionally used in Chinese folk medicine for the treatment of infectious diseases. It is a rich source of prenylated phenolic compounds that have been extensively studied for their promising biological activities. AIM OF THE STUDY: Due to the increasing development of antibiotic resistance, our study investigated plant-derived natural products from the fruits of P. tomentosa that could control Staphylococcus aureus infections with novel targets/modes of action and reduce antimicrobial resistance. MATERIALS AND METHODS: The ethanolic extract was fractionated and detected by liquid chromatography. The antistaphylococcal effects of the plant formulations were studied in detail in vitro by various biological methods, including microdilution methods for minimum inhibitory concentration (MIC), the checkerboard titration technique for synergy assay, fluorescence measurements for membrane disruption experiments, autoinducer-2-mediated bioassay for quorum sensing inhibition, and counting of colony-forming units for relative adhesion. Morphology was examined by transmission electron microscopy. RESULTS: Total ethanolic extract and chloroform fraction showed MICs of 128 and 32 µg/mL, respectively. Diplacol, diplacone, and 3'-O-methyl-5'-hydroxydiplacone inhibited S. aureus growth in the range of 8-16 µg/mL. Synergistic potential was shown in combination with mupirocin and fusidic acid. The ethanolic extract and the chloroform fraction destroyed the cell membranes by 91.61% and 79.46%, respectively, while the pure compounds were less active. The ethanolic extract and the pure compounds reduced the number of adhered cells to 47.33-10.26% compared to the untreated control. All tested plant formulations, except diplacone, inhibited quorum sensing of S. aureus. Transmission electron microscopy showed deformation of S. aureus cells. CONCLUSIONS: The products from the fruit of P. tomentosa showed antimicrobial properties against S. aureus alone and in combination with antibiotics. By affecting intracellular targets, geranylated flavonoids proposed novel approaches in the control of staphylococcal infections.


Assuntos
Anti-Infecciosos , Lamiales , Infecções Estafilocócicas , Staphylococcus aureus , Frutas/química , Extratos Vegetais/química , Clorofórmio , Anti-Infecciosos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Etanol/farmacologia
5.
Plants (Basel) ; 12(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38005794

RESUMO

Tropaeolum majus L. is a traditional medicinal plant with a wide range of biological activities due to the degradation products of the glucosinolate glucotropaeolin. Therefore, the goals of this study were to identify volatiles using gas chromatography-mass spectrometry analysis (GC-MS) of the hydrosols (HYs) isolated using microwave-assisted extraction (MAE) and microwave hydrodiffusion and gravity (MHG). Cytotoxic activity was tested against a cervical cancer cell line (HeLa), human colon cancer cell line (HCT116), human osteosarcoma cell line (U2OS), and healthy cell line (RPE1). The effect on wound healing was investigated using human keratinocyte cells (HaCaT), while the antibacterial activity of the HYs was tested against growth and adhesion to a polystyrene surface of Staphylococcus aureus and Escherichia coli. Antiphytoviral activity against tobacco mosaic virus (TMV) was determined. The GC-MS analysis showed that the two main compounds in the HYs of T. majus are benzyl isothiocyanate (BITC) and benzyl cyanide (BCN) using the MAE (62.29% BITC and 15.02% BCN) and MHG (17.89% BITC and 65.33% BCN) extraction techniques. The HYs obtained using MAE showed better cytotoxic activity against the tested cancer cell lines (IC50 value of 472.61-637.07 µg/mL) compared to the HYs obtained using MHG (IC50 value of 719.01-1307.03 µg/mL). Both concentrations (5 and 20 µg/mL) of T. majus HYs using MAE showed a mild but statistically non-significant effect in promoting gap closure compared with untreated cells, whereas the T. majus HY isolated using MHG at a concentration of 15 µg/mL showed a statistically significant negative effect on wound healing. The test showed that the MIC concentration was above 0.5 mg/mL for the HY isolated using MAE, and 2 mg/mL for the HY isolated using MHG. The HY isolated using MHG reduced the adhesion of E. coli at a concentration of 2 mg/mL, while it also reduced the adhesion of S. aureus at a concentration of 1 mg/mL. Both hydrosols showed excellent antiphytoviral activity against TMV, achieving100% inhibition of local lesions on the leaves of infected plants, which is the first time such a result was obtained with a hydrosol treatment. Due to the antiphytoviral activity results, hydrosols of T. majus have a promising future for use in agricultural production.

6.
Food Technol Biotechnol ; 61(3): 410-411, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38022875
7.
J Verbrauch Lebensm ; 18(2): 133-146, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265593

RESUMO

Understanding consumers' behavior and their handling of high-risk foods at home is essential for reducing the number of foodborne illnesses. This study shows the results of a cross-national analysis of consumers' perception from nine countries, and the identification of customers' clusters and its characteristics in order to understand customers' behavior, and to build safe chilled ready-to-eat (RTE) foods prevention strategies. The cluster analysis resulted in two clusters: (1) "Precautious consumers" characterized by the orientation towards pre-packed RTE foods, with consumers mainly coming from Bosnia and Herzegovina, India, Poland, Portugal, Spain, and Turkey. Their attitudes and self-reported practices may be categorized as less risky in terms of food-borne illnesses connected with the consumption of RTE foods; (2) "Unconcerned consumers" preferred cutting and slicing RTE foods freshly at the point of purchase, usually sold at the delicatessen department in a supermarket or at open markets. Those consumers mostly came from Croatia, Serbia and Slovenia and their attitudes and self-reported practices were riskier. These results allow a better understating of what characterizes consumers of RTE foods in different countries.

8.
Int J Food Microbiol ; 394: 110159, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-36924752

RESUMO

Pseudomonas spp. are widely distributed bacteria on surfaces in the food production and processing environment, where they form extracellular polymeric substance rich biofilms that interact with other bacteria. In this study, the influence of biofilm of Pseudomonas fragi ATCC 4973 on Listeria monocytogenes ATCC 19115 and Campylobacter jejuni NCTC 11168 was investigated at 5 °C and 15 °C on stainless steel in broth and food homogenates (fish or chicken meat). Stainless steel was then coated with PVDF-HFP/PVP/MoO3 nanocomposite and examined for surface changes (scanning electron microscope, static contact angle, Vickers hardness and elastic modulus). The effect of the prepared nanocomposite coating on P. fragi and on L. monocytogenes and C. jejuni was evaluated in mono- and co-culture. P. fragi produced more biofilm at 15 °C than at 5 °C, especially when food homogenates were used as growth media. Co-cultivation with pathogens did not affect biofilm production by P. fragi, but significant changes were observed in L. monocytogenes and C. jejuni, resulting in a decrease and increase, respectively, in the determined number of culturable biofilm cells. The first change was probably due to competition for the surface, and the second to the oxygen gradient. Stainless steel was then coated with a PVDF-HFP/PVP/MoO3 nanocomposite, which was characterised by lower roughness and higher wettability, but lower hardness compared to uncoated stainless steel. The prepared nanocoating showed bactericidal activity when tested in phosphate buffered saline. When used in food homogenates, a reduction of over 95 % in bacterial counts was observed. An abundant biofilm of P. fragi proved protective to L. monocytogenes and C. jejuni against the functionalised nanocomposite surface when tested in food homogenates. The control of spoilage Pseudomonas spp., which are common in the food production and processing environment, is important for reducing the contamination of food with spoilage bacteria and with pathogens such as L. monocytogenes and C. jejuni, which may be present in the same environment. The PVDF-HFP/PVP/MoO3 nanocomposite showed good potential for use as a coating for food contact surfaces, but possible migration of nanoparticles from the nanocomposite coating to food should be evaluated before its commercial use.


Assuntos
Campylobacter jejuni , Listeria monocytogenes , Pseudomonas fragi , Animais , Aço Inoxidável/análise , Temperatura , Matriz Extracelular de Substâncias Poliméricas/química , Biofilmes , Pseudomonas , Microbiologia de Alimentos , Aderência Bacteriana , Contagem de Colônia Microbiana
9.
Microbiol Spectr ; : e0257222, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36722966

RESUMO

The full role of the luxS gene in the biological processes, such as essential amino acid synthesis, nitrogen and pyruvate metabolism, and flagellar assembly, of Campylobacter jejuni has not been clearly described to date. Therefore, in this study, we used a comprehensive approach at the cellular and molecular levels, including transcriptomics and proteomics, to investigate the key role of the luxS gene and compared C. jejuni 11168ΔluxS (luxS mutant) and C. jejuni NCTC 11168 (wild type) strains. Transcriptomic analysis of the luxS mutant grown under optimal conditions revealed upregulation of luxS mutant metabolic pathways when normalized to wild type, including oxidative phosphorylation, carbon metabolism, citrate cycle, biosynthesis of secondary metabolites, and biosynthesis of various essential amino acids. Interestingly, induction of these metabolic pathways was also confirmed by proteomic analysis, indicating their important role in energy production and the growth of C. jejuni. In addition, genes important for the stress response of C. jejuni, including nutrient starvation and oxidative stress, were upregulated. This was also evident in the better survival of the luxS mutant under starvation conditions than the wild type. At the molecular level, we confirmed that metabolic pathways were upregulated under optimal conditions in the luxS mutant, including those important for the biosynthesis of several essential amino acids. This also modulated the utilization of various carbon and nitrogen sources, as determined by Biolog phenotype microarray analysis. In summary, transcriptomic and proteomic analysis revealed key biological differences in tricarboxylic acid (TCA) cycle, pyruvate, nitrogen, and thiamine metabolism as well as lipopolysaccharide biosynthesis in the luxS mutant. IMPORTANCE Campylobacter jejuni is the world's leading foodborne bacterial pathogen of gastrointestinal disease in humans. C. jejuni is a fastidious but widespread organism and the most frequently reported zoonotic pathogen in the European Union since 2005. This led us to believe that C. jejuni, which is highly sensitive to stress factors (starvation and oxygen concentration) and has a low growth rate, benefits significantly from the luxS gene. The role of this gene in the life cycle of C. jejuni is well known, and the expression of luxS regulates many phenotypes, including motility, biofilm formation, host colonization, virulence, autoagglutination, cellular adherence and invasion, oxidative stress, and chemotaxis. Surprisingly, this study confirmed for the first time that the deletion of the luxS gene strongly affects the central metabolic pathway of C. jejuni, which improves its survival, showing its role beyond the intercellular signaling system.

10.
Nat Prod Res ; 37(23): 4018-4022, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36565292

RESUMO

The aim of the study was to investigate the essential oil (EO) of Lavandula x intermedia cv. Bila, which has not been studied before. The EOs were distilled from plants collected in two consecutive years on the island of Hvar (Croatia) and in the Karst (Slovenia) and analysed for chemical composition and antimicrobial activity. The main component of EOs was linalool, but the EOs from Hvar had higher contents of Z-ß-ocimene and borneol + lavandulol than the EOs from Karst, in which camphor, linalyl acetate and 1,8-cineole predominated. The antimicrobial activity was evaluated using the minimum inhibitory concentration and proved that the EOs were effective against Candida spp. Studies have shown that the composition of L. x intermedia EO depends on the variety and the climatic and geographical characteristics of the plant growth. The antimicrobial activity of EO is also influenced by the type and strain of microorganisms involved in the research.


Assuntos
Anti-Infecciosos , Lavandula , Óleos Voláteis , Óleos Voláteis/farmacologia , Croácia , Cânfora , Anti-Infecciosos/farmacologia
11.
Foods ; 11(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36496658

RESUMO

Seaweeds are a potentially sustainable source of natural antioxidants that can be used in the food industry and possibly for the development of new sustainable packaging materials with the ability to extend the shelf-life of foods and reduce oxidation. With this in mind, the seasonal variations in the chemical composition and antioxidant activity of brown seaweed (Padina pavonica) extracts were investigated. The highest total phenolic content (TPC) and antioxidant activity (measured by ferric reducing/antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and oxygen radical absorbance capacity (ORAC)) were found for P. pavonica June extract. The TPC of 26.69 ± 1.86 mg gallic acid equivalent/g, FRAP of 352.82 ± 15.41 µmole Trolox equivalent (TE)/L, DPPH of 52.51 ± 2.81% inhibition, and ORAC of 76.45 ± 1.47 µmole TE/L were detected. Therefore, this extract was chosen for the development of bioactive PLA bilayer film, along with chitosan. Primary or quaternary chitosan was used as the first layer on polylactic acid (PLA) films. A suspension of chitosan particles with entrapped P. pavonica extract was used as the second layer. X-ray photoelectron spectroscopy confirmed the presence of layers on the material surface. The highest recorded antioxidant activity of the newly developed films was 63.82% inhibition. The developed functional films exhibited antifogging and antioxidant properties, showing the potential for application in the food industry.

12.
RSC Adv ; 12(48): 31235-31245, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36349039

RESUMO

Synthesis of zinc oxide (ZnO) nanoparticles (NPs) was mediated by plant extracts to assist in the reduction of zinc atoms during the synthesis and act as a capping agent during annealing. The preparation used ethanolic extracts from the roots of Japanese knotweed (Fallopia japonica). Two major outcomes could be made. (i) A synergistic effect of multiple polyphenolic components in the extract is needed to achieve the capping effect of crystallite growth during thermal annealing at 450 °C characterized by an exponential growth factor (n) of 4.4 compared to n = 3 for bare ZnO. (ii) Synergism between the ZnO NPs and plant extracts resulted in superior antimicrobial activity against both Gram-positive bacteria, e.g., Staphylococcus aureus, and Gram-negative bacteria, e.g., Escherichia coli and Campylobacter jejuni. The materials were also tested for their antimicrobial activity against S. aureus under ultraviolet (UV) illumination. Also here, the photocatalyst prepared with plant extracts was found to be superior. The residues of the plant extract molecules on the surface of the catalyst were identified as the main cause of the observed differences, as proved by thermal gravimetry. Such a preparation using ethanolic extract of Fallopia japonica could serve as a more controlled synthesis of ZnO and potentially other metal oxides, with low environmental impact and high abundance in nature.

13.
Antioxidants (Basel) ; 11(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36139730

RESUMO

Phenolic profiles, antioxidant, and antimicrobial activities of hydroethanolic olive leaf extracts from six Mediterranean olive cultivars (Croatian: Lastovka, Levantinka, Oblica; Italian: Moraiolo, Frantoio, Nostrana di Brisighella) were investigated. As expected, various distributions of phenolic levels were observed for each cultivar and the total phenolic content showed high variability (ranging from 4 to 22 mg GAE/g of dry extract), with the highest amount of phenolics found in the Oblica sample, which also provided the highest antiradical (ORAC) and reducing activity (FRAP). The screening of individual compounds was performed by HPLC-PDA-ESI-QTOF-MS and the main detected compounds were oleuropein, hydroxytyrosol, oleoside/secologanoside, verbascoside, rutin, luteolin glucoside, hydroxyoleuropein, and ligstroside. While the antioxidant activity of the samples was relatively high, they showed no bactericidal and bacteriostatic activity against E. coli and S. Typhimurium; weak activity against Staphylococcus aureus, Bacillus cereus, and Listeria innocua; and inhibitory effects against Campylobacter jejuni at 0.5 mg dry extract/mL. The obtained results support the fact that olive leaf extracts, and especially those from the Oblica cultivar, could potentially be applied in various industries as natural preservatives and effective and inexpensive sources of valuable antioxidants.

14.
Antibiotics (Basel) ; 11(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36140000

RESUMO

Campylobacter jejuni is a major foodborne pathogen and the leading cause of bacterial gastroenteritis, i.e., campylobacteriosis. Besides searching for novel antimicrobials, identification of new targets for their action is becoming increasingly important. Rhodiola rosea has long been used in traditional medicine. Ethanolic extracts from the roots and rhizomes of the plant contain a wide range of bioactive compounds with various pharmacological activities. In this study, cultivated plant materials have been used, i.e., "Mattmark" and "Rosavine". Through optimized protocols, we obtained fractions of the initial ethanolic extracts rich in most important bioactive compounds from R. rosea, including salidroside, rosavins, proanthocyanidins (PACs), and flavonoids. The antimicrobial activity in relation to the chemical composition of the extracts and their fractions was studied with an emphasis on C. jejuni AI-2-mediated intercellular signaling. At concentration 15.625 mg/L, bioluminescence reduction rates varied from 27% to 72%, and the membrane remained intact. Fractions rich in PACs had the strongest antimicrobial effect against C. jejuni, with the lowest minimal inhibitory concentrations (MICs) (M F3 40%: 62.5 mg/L; R F3 40%: 250 mg/L) and the highest intercellular signaling reduction rates (M F3 40%: 72%; R F3 40%: 65%). On the other hand, fractions without PACs were less effective (MICs: M F5 PVP: 250 mg/L; R F5 PVP: 1000 mg/L and bioluminescence reduction rates: M F5 PVP: 27%; R F5 PVP: 43%). Additionally, fractions rich in flavonoids had strong antimicrobial activity (MICs: M F4 70%: 125 mg/L; R F4 70%: 250 mg/L and bioluminescence reduction rates: M F4 70%: 68%; R F4 70%: 50%). We conclude that PACs and flavonoids are crucial compound groups responsible for the antimicrobial activity of R. rosea roots and rhizomes in C. jejuni.

15.
Sci Rep ; 12(1): 13158, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915316

RESUMO

The consumers' demand for safe foods without chemical additives increased the research for green solutions, based on natural antimicrobials. Plants can be an important source of bioactive compounds able to prevent the development of foodborne pathogens and spoilage microflora. This paper aimed to characterize phenolic extracts (PEs) and essential oils (EOs) obtained from Mediterranean Rubus fruticosus leaves and Juniperus oxycedrus needles and to evaluate their antimicrobial effects against Listeria monocytogenes Scott A. The growth dynamics with sub-lethal concentrations of plant derivatives were modeled and flow cytometry was used to better evidence the effect on cell viability and culturability. The results showed that these plant derivatives affected the growth of L. monocytogenes, increasing lag phase (about 40 h in the presence of PEs vs. 8 h in the control) and decreasing the final cell load of at least 1 log cycle with respect to the control. R. fruticosus EO was the most effective, determining an initial decrease of cell counts of about 6 log cycles, followed by a restart of growth after 10 h, with rate similar to the control (0.08 with R. fruticosus EO vs. 0.09 ((log CFU/ml)/h in the control) but significantly lower final cell load (7.33 vs. 8.92 log CFU/ml). According to flow cytometry, only R. fruticosus EO induced a relevant increase of dead cells, while the other plant derivatives determined different extent of sub-lethal cell injury. The discrepancy observed in some cases between viability and culturability could indicate the presence of cells not able to grow in culture media, whose fate needs to be further investigated to assess their potential recovery, thus bringing to an overestimation of the antimicrobial effect of these substances. This research contributed to increase the knowledge of these underused raw materials such as blackberry leaves and juniper needles that can be exploited in food and other industries.


Assuntos
Juniperus , Listeria monocytogenes , Óleos Voláteis , Rubus , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Óleos Voláteis/farmacologia , Rubus/química
16.
Front Microbiol ; 13: 910616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875550

RESUMO

Campylobacter jejuni is the leading cause of bacterial gastroenteritis, or campylobacteriosis, in humans worldwide, and poultry serves as a major source of infection. To reduce the risk associated with C. jejuni transmission via poultry meat, effective interventions during poultry production are needed, and the use of probiotics is a promising approach. In this study, 15 Bacillus subtilis strains were initially screened for their anti-Campylobacter activities. B. subtilis PS-216 strain demonstrated the best anti-Campylobacter activity against 15 C. jejuni isolates when examined using in vitro co-cultures. To evaluate the suitability of B. subtilis PS-216 for probiotic use, its susceptibility to eight clinically important antimicrobials and simulated gastric conditions was investigated. B. subtilis PS-216 was sensitive to all of the tested antibiotics. Although vegetative cells were sensitive to gastric conditions, B. subtilis PS-216 spores were highly resistant. We further evaluated the use of a B. subtilis PS-216 spore preparation (2.5 × 106 CFU/mL water) to prevent and/or reduce C. jejuni colonization in broiler chickens in vivo. Compared to the untreated group, significantly lower Campylobacter counts were detected in caeca of broilers continuously treated with B. subtilis PS-216 spores in their drinking water. Furthermore, broilers continuously treated with B. subtilis PS-216 spores showed improved weight gain, compared to the control group. Together, these results demonstrate the potential of B. subtilis PS-216 for use in poultry to reduce C. jejuni colonization and improve weight gain.

17.
J Food Sci Technol ; 59(4): 1429-1439, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35250067

RESUMO

Obtaining high-quality value-added bread with extended shelf-life by utilizing food industry by-products that would have minimal negative effect on gluten structure while avoiding the usage of synthetic preservatives, was the challenge of this study. For this purpose the influence of the combination of carob pod flour (C, 0-15%), sugar beet fibers (F, 0-10%) and sugar beet molasses (M, 0-6%) on dough rheology and bread quality was investigated. Selected materials were of good microbiological quality, while carob flour and sugar beet fibers were rich in dietary fibers (43.6% and 67.0%, respectively). The presence of high share of dietary fibers (combination of C and F) increased dough resistance to extension up to 2.5 times, while dough extensibility was reduced by 50%. The addition of molasses had less pronounced single effect on dough properties however its impact in combination with fiber-rich materials outweighed the individual effect (an increase of dough resistance at about 55%). Molasses alone and in combination with other ingredients had positive effect on bread quality. Sample M6F5 attained crumb quality score (6.0 of maximum 7.0) higher than in control sample (5.6). High share of C and F reduced loaf volume and crumb quality of bread up to 56% and 50%, respectively and increased hardness 7.5 times. However, carob flour (7.5%) increased polyphenols content and antioxidant capacity 3 and 4 times, respectively. Moreover, carob flour and molasses and their combination showed inhibitory effect on mold mycelia growth and spores formation. Regarding all of the above, C7.5M3F5 was chosen as optimal sample.

18.
Microorganisms ; 10(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35208741

RESUMO

As the incidence of Campylobacter jejuni and campylobacteriosis grows, so does the need for a better understanding and control of this pathogen. We studied the interactions of C. jejuni NCTC 11168 and a potential probiotic, Bacillus subtilis PS-216, in cocultures at different starting ratios and temperatures (20 °C, 37 °C, 42 °C), under different atmospheres (aerobic, microaerobic), and in different growth media (Mueller-Hinton, chicken litter medium, chicken intestinal-content medium). Under microaerobic conditions, B. subtilis effectively inhibited the growth of C. jejuni at 42 °C (log reduction, 4.19), even when C. jejuni counts surpassed B. subtilis by 1000-fold in the starting inoculum. This inhibition was weaker at 37 °C (log reduction, 1.63), while no impact on CFUs was noted at 20 °C, which is a temperature nonpermissive of C. jejuni growth. Under aerobic conditions, B. subtilis supported C. jejuni survival. B. subtilis PS-216 inhibited the growth of C. jejuni in sterile chicken litter (4.07 log reduction) and in sterile intestinal content (2.26 log reduction). In nonsterile intestinal content, B. subtilis PS-216 was able to grow, to a lesser extent, compared to Mueller-Hinton media, still showing potential as a chicken probiotic that could be integrated into the chicken intestinal microbiota. This study showed the strong influence of environmental parameters on the variability of C. jejuni and B. subtilis interactions. Furthermore, B. subtilis PS-216 antagonism was strongest against C. jejuni NCTC 11168 under conditions that might represent conditions in the chicken environment (42 °C, microaerobic atmosphere, chicken litter medium).

19.
Food Technol Biotechnol ; 60(4): 533-542, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36816870

RESUMO

Research background: Plant Tropaeolum majus L. (garden nasturtium) belongs to the family Tropaeolaceae and contains benzyl glucosinolate. The breakdown product of benzyl glucosinolate, benzyl isothiocyanate (BITC), exhibits various biological activities such as antiproliferative, antibacterial and antiinflammatory. In order to optimize the content of biologically active volatile compounds in plant extract and essential oil, the use of appropriate extraction technique has a crucial role. Experimental approach: The current study investigates the effect of two modern extraction methods, microwave-assisted distillation (MAD) and microwave hydrodiffusion and gravity (MHG), on the chemical composition of volatile components present in the essential oil and extract of garden nasturtium (T. majus L. var. altum) seeds. Investigation of the biological activity of samples (essential oil, extract and pure compounds) was focused on the antiproliferative effect against different cancer cell lines: cervical cancer cell line (HeLa), human colon cancer cell line (HCT116) and human osteosarcoma cell line (U2OS), and the antibacterial activity which was evaluated against the growth and adhesion of Staphylococcus aureus and Escherichia coli to polystyrene surface. Results and conclusions: Essential oil and extract of garden nasturtium (T. majus) seeds were isolated by two extraction techniques: MAD and MHG. BITC and benzyl cyanide (BCN) present in the extract were identified by gas chromatography-mass spectrometry. Essential oil of T. majus showed higher antiproliferative activity (IC50<5 µg/mL) than T. majus extract (IC50<27 µg/mL) against three cancer cell lines: HeLa, HCT116 and U2OS. BITC showed much higher inhibitory effect on all tested cells than BCN. The essential oil and extract of T. majus showed strong antimicrobial activity against S. aureus and E. coli. Novelty and scientific contribution: This work represents the first comparative report on the antiproliferative activity of the essential oil and extract of T. majus seeds, BITC and BCN against HeLa, HCT116 and U2OS cells as well as their antimicrobial activity against S. aureus and E. coli. This study demonstrates that the essential oil of T. majus seeds exhibits stronger antiproliferative and antimicrobial activity than the plant extract.

20.
Foods ; 10(11)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34828970

RESUMO

The wide array of spontaneously fermented sausages of the Mediterranean area can represent a reservoir of microbial biodiversity and can be an important source of new technological and functional strains able to preserve product properties, counteracting the impoverishment of their organoleptic typical features due to the introduction of commercial starter cultures. We analysed 15 artisanal salamis from Italy, Spain, Croatia and Slovenia to evaluate the microbiota composition, through culture-dependent and culture-independent techniques (i.e., metagenomic analysis), chemical-physical features, biogenic amines and aroma profile. The final pH varied according to origin and procedures (e.g., higher pH in Italian samples due to long ripening and mold growth). Lactic acid bacteria (LAB) and coagulase-negative cocci (CNC) were the dominant population, with highest LAB counts in Croatian and Italian samples. Metagenomic analysis showed high variability in qualitative and quantitative microbial composition: among LAB, Latilactobacillus sakei was the dominant species, but Companilactobacillus spp. was present in high amounts (45-55% of the total ASVs) in some Spanish sausages. Among staphylococci, S. epidermidis, S. equorum, S. saprophyticus, S. succinus and S. xylosus were detected. As far as biogenic amines, tyramine was always present, while histamine was found only in two Spanish samples. These results can valorize the bacterial genetic heritage present in Mediterranean products, to find new candidates of autochthonous starter cultures or bioprotective agents.

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