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2.
Food Chem ; 441: 138276, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38215501

RESUMO

House crickets are expected to play a significant role in the future food sector. Electrohydrodynamic (EHD) drying offers an environmentally friendly alternative to conventional drying methods. Pulsed electric fields (PEF) is a non-thermal process that facilitates conventional processes. EHD was applied to house crickets with and without PEF pretreatment, and the effect of PEF and EHD on the quality of the insects was evaluated. PEF pretreatment positively affected the oven drying at 60 °C by reducing its duration and thus decreasing the energy consumption by 14.22%. Moisture removal of EHD was not sufficient to replace oven drying, but when combined with oven drying, the overall energy consumption was reduced by >50%. PEF processing also increased the protein solubility (53.07% higher than the respective control) and antioxidant activity (24.05% higher than the respective control) of the oven-dried samples and reduced the histamine content of the EHD-dried samples (25.87% lower than the respective control).


Assuntos
Gryllidae , Animais , Farinha , Dessecação/métodos , Antioxidantes , Solubilidade
3.
Heliyon ; 10(11): e32342, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38947460

RESUMO

This study investigates the potential of yacon (Smallanthus sonchifolius) juice for the development of prebiotic-rich organic apple-based snacks. Yacon syrup, primarily composed of fructan, inulin, fructooligosaccharides (FOS), and free sugars, represents a promising nutraceutical product. Its great potential in food processing, particularly as an innovative source of prebiotics, has been demonstrated both in vitro and in vivo since it is fermented specifically by lactobacilli and bifidobacteria. Our objective was to explore the feasibility of employing vacuum impregnation process to incorporate yacon juice into organic apples, followed by hot air drying for the formulation of dried organic apple-based snacks with health-enhancing attributes. We assessed the prebiotic and physicochemical characteristics of the impregnated snacks, also considering 50 days of storage at room temperature. Vacuum impregnation and air drying produced dried apple slices impregnated with yacon juice with good quality and stability. Higher levels of fructan (16-fold difference compared to non-impregnated apples) in the apple slices increased their prebiotic potential, promoting the growth and viability of cells within simulated intestinal fluid, including strains of Bifidobacterium animalis subsp. lactis BB -12, Bifidobacterium breve DSM 20091, Bifidobacterium longum subsp. infantis DSM 20088, Lacticaseibacillus rhamnosus GG and Lacticaseibacillus rhamnosus C112, even after prolonged storage. Remarkably, the physicochemical parameters of the impregnated and dried apple slices remained nearly constant and akin to the control samples. Therefore, the combination of vacuum impregnation and air drying has the potential to be used to produce enriched prebiotic organic apple snacks, providing consumers with additional health benefits, including enhanced gut health, with its associated implications, and increased satiety. This innovation could contribute to the development of health-promoting food products with improved nutritional profiles.

4.
Foods ; 13(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928888

RESUMO

Kombucha is a trending tea fermented via a complex microflora of yeasts and acetic acid bacteria. It can be a valid low-calorie substitute for soft drinks due to its sour, naturally carbonated, and sweet taste. Despite increased interest, the microflora and functional properties of kombucha have not yet been fully understood. The aim of this work was to characterize, from a microbiological, chemico-physical, and functional point of view, three types of artisanal kombucha obtained by fermenting green tea containing sugar by means of different starter cultures. Metagenomic analysis revealed a predominance of yeasts compared to bacteria, regardless of the sample. In particular, Brettanomyces spp. was found to be the dominant yeast. Moreover, the different types of kombucha had different microbial patterns in terms of acetic acid bacteria and yeasts. Ethanol and acetic acid were the dominant volatile molecules of the kombucha volatilome; the samples differed from each other in terms of their content of alcohols, esters, and acids. All the samples showed a high antioxidant potential linked to the high content of phenols. This study confirmed the positive chemico-physical and functional properties of kombucha and indicated that the microflora responsible for the fermentation process can significantly affect the characteristics of the final product.

5.
Foods ; 13(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38338584

RESUMO

The main objective of this work was to evaluate the combined effect of a biotechnology process, based on selected yeast strains, and a high-pressure homogenization (HPH) treatment on the microbiological quality, structural organization of proteins, chitin content, and antioxidant activity of a mixture of cricket powder (Acheta domesticus) and water. Compared to untreated samples, the cricket matrix treated with HPH four times at 180 MPa promoted the growth of the inoculated Yarrowia lipolytica and Debaryomyces hansenii strains. HPH did not affect the concentration of chitin; however, the combination with microorganisms tended to reduce the content. Although the antioxidant activity increased from 0.52 to 0.68 TAC mM/TE after a 48 h incubation in the control, it was further improved by the combination of HPH and D. hansenii metabolism, reaching a value of 0.77 TAC mM/TE. The combination of the two approaches also promoted a reduction in the intensity of bands with molecular weights between 31 and 21.5 kDa in favor of bands with a lower molecular weight. In addition, HPH treatment reduced the number of accessible thiols, suggesting protein structure changes that may further impact the technological properties of cricket powder.

6.
Biochim Biophys Acta ; 1823(4): 800-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22230191

RESUMO

The responses of AMP-activated protein kinase (AMPK) and Ornithine decarboxylase (ODC) to isoproterenol have been examined in H9c2 cardiomyoblasts, AMPK represents the link between cell growth and energy availability whereas ODC, the key enzyme in polyamine biosynthesis, is essential for all growth processes and it is thought to have a role in the development of cardiac hypertrophy. Isoproterenol rapidly induced ODC activity in H9c2 cardiomyoblasts by promoting the synthesis of the enzyme protein and this effect was counteracted by inhibitors of the PI3K/Akt pathway. The increase in enzyme activity became significant between 15 and 30min after the treatment. At the same time, isoproterenol stimulated the phosphorylation of AMPKα catalytic subunits (Thr172), that was associated to an increase in acetyl coenzyme A carboxylase (Ser72) phosphorylation. Downregulation of both α1 and α2 isoforms of the AMPK catalytic subunit by siRNA to knockdown AMPK enzymatic activity, led to superinduction of ODC in isoproterenol-treated cardiomyoblasts. Downregulation of AMPKα increased ODC activity even in cells treated with other adrenergic agonists and in control cells. Analogue results were obtained in SH-SY5Y neuroblastoma cells transfected with a shRNA construct against AMPKα. In conclusion, isoproterenol quickly activates in H9c2 cardiomyoblasts two events that seem to contrast one another. The first one, an increase in ODC activity, is linked to cell growth, whereas the second, AMPK activation, is a homeostatic mechanism that negatively modulates the first. The modulation of ODC activity by AMPK represents a mechanism that may contribute to control cell growth processes.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Mioblastos Cardíacos/enzimologia , Ornitina Descarboxilase/metabolismo , Animais , Cardiomegalia/enzimologia , Cardiomegalia/patologia , Regulação para Baixo/efeitos dos fármacos , Eflornitina/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Isoproterenol/farmacologia , Mioblastos Cardíacos/efeitos dos fármacos , Mioblastos Cardíacos/patologia , Ornitina Descarboxilase/genética , Inibidores da Ornitina Descarboxilase , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos
7.
Foods ; 12(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37685221

RESUMO

The use of plant extracts (e.g., essential oils and their active compounds) represents an interesting alternative to chemical additives and preservatives applied to delay the alteration and oxidation of foods during their storage. Essential oils (EO) are nowadays considered valuable sources of food preservatives as they provide a healthier alternative to synthetic chemicals while serving the same purpose without affecting food quality parameters. The natural antimicrobial molecules found in medicinal plants represent a possible solution against drug-resistant bacteria, which represent a global health problem, especially for foodborne infections. Several solutions related to their application on food have been described, such as incorporation in active packaging or edible film and direct encapsulation. However, the use of bioactive concentrations of plant derivatives may negatively impact the sensorial characteristics of the final product, and to solve this problem, their application has been proposed in combination with other hurdles, including biocontrol agents. Biocontrol agents are microbial cultures capable of producing natural antimicrobials, including bacteriocins, organic acids, volatile organic compounds, and hydrolytic enzymes. The major effect of bacteriocins or bacteriocin-producing LAB (lactic acid bacteria) on food is obtained when their use is combined with other preservation methods. The combined use of EOs and biocontrol agents in fruit and vegetables, meat, and dairy products is becoming more and more important due to growing concerns about potentially dangerous and toxic synthetic additives. The combination of these two hurdles can improve the safety and shelf life (inactivation of spoilage or pathogenic microorganisms) of the final products while maintaining or stabilizing their sensory and nutritional quality. This review critically describes and collects the most updated works regarding the application of EOs in different food sectors and their combination with biocontrol agents and bacteriocins.

8.
Molecules ; 17(6): 6982-95, 2012 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-22728370

RESUMO

Chemical constituents of liverwort (Porella cordaeana) extracts have been identified using solid-phase microextraction-gas chromatography mass spectrometry (SPME-GC/MS). The methanol, ethanol and ethyl acetate extracts were rich in terpenoids such as sesquiterpene hydrocarbons (53.12%, 51.68%, 23.16%), and monoterpene hydrocarbons (22.83%, 18.90%, 23.36%), respectively. The dominant compounds in the extracts were ß-phellandrene (15.54%, 13.66%, 12.10%) and ß-caryophyllene (10.72%, 8.29%, 7.79%, respectively). The antimicrobial activity of the extracts was evaluated against eleven food microorganisms using the microdilution and disc diffusion methods. The minimum inhibitory concentration (MIC) varied from 0.50 to 2.00 mg/mL for yeast strains (Saccharomyces cerevisiae 635, Zygosacharomyces bailii 45, Aerobasidium pullulans L6F, Pichia membranaefaciens OC 71, Pichia membranaefaciens OC 70, Pichia anomala CBS 5759, Pichia anomala DBVPG 3003 and Yarrowia lipolytica RO13), and from 1.00 to 3.00 mg/mL for bacterial strains (Salmonella enteritidis 155, Escherichia coli 555 and Listeria monocytogenes 56Ly). Methanol extract showed better activity in comparison with ethanol and ethyl acetate extracts. High percentages of monoterpene and sesquiterpene hydrocarbons could be responsible for the better antimicrobial activity.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Hepatófitas/química , Extratos Vegetais/química , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia , Bactérias/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Microextração em Fase Sólida , Leveduras/efeitos dos fármacos
9.
Food Res Int ; 159: 111589, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35940789

RESUMO

Sublethal HPH treatments have been demonstrated to impact the technological properties and functions of treated microorganisms by inducing specific enzymes/genes or modulating membrane structures and inducing autolysis. In this work, the early effects of a 100 MPa HPH treatment on the winery starter Saccharomyces cerevisiae ALEAFERM AROM grown in synthetic must were assessed. While there were no differences in cell cultivability during the first 48 h between treated and untreated cells, a reduction in volatile metabolites released by HPH-treated cells during the first 2 h was observed. This reduction was only temporary since after 48 h, volatile molecules reached similar or even higher concentrations compared with the control. Moreover, the gene expression response of HPH-treated cells was evaluated after 1 h of incubation and compared with that of untreated cells. A massive rearrangement of gene expression was observed with the identification of 1220 differentially expressed genes (DEGs). Most of the genes related to energetic metabolic pathways and ribosome structure were downregulated, while genes involved in ribosome maturation, transcription, DNA repair, response to stimuli and stress were upregulated. These findings suggest that HPH induces or promotes an autolytic-like behaviour that can be exploited in winemaking.


Assuntos
Saccharomyces cerevisiae , Autólise , Expressão Gênica , Humanos , Saccharomyces cerevisiae/genética
10.
Front Nutr ; 9: 1092172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36712524

RESUMO

Introduction: Enterococci are lactic acid bacteria (LAB) usually found as food contaminants in fermented products such as cheeses and fermented sausages. Due to their antibiotic resistance, the presence of virulence factors, and the ability to produce biogenic amines (BAs), the determination of these bacteria is crucial to assure food quality and safety. BAs production and consequent accumulation in foods can cause toxicological effects on human health. Plant phenolic compounds are promising alternatives to chemical preservatives and reflect consumers' demand for "green" solutions. In this study, the antimicrobial effect of blackberry (Rubus fruticosus) leaves and prickly juniper (Juniperus oxycedrus) needles, both as phenolic extracts (PE) and essential oils (EO), were evaluated against Enterococcus faecium FC12, a known tyramine-producing strain. Methods: The growth kinetics in the presence of sub-lethal concentrations of such plant derivatives were modeled (Gompertz equation) and BA production was monitored over time by HPLC. Moreover, flow cytometry (FCM) was used to study the effects of EOs and PEs on cell viability. Results: The EOs showed a higher antimicrobial effect (especially R. fruticosus added at 0.75 mg/ml), determining an initial decrease of culturable cells followed by a recovery, even if with lower growth rates and final cell loads. Different rates of BA formation were observed, with tyramine concentrations ranging from 120 to 160 mg/l after 96 h of incubation, and 2-phenylethylamine was produced in lower amounts, usually after reaching the peak of tyramine. FCM confirmed the higher efficacy of R. fruticosus EO that induced cell membrane injury in 93% of the total population. However, complete recovery occurred in the following incubation, demonstrating transient damage. Discussion: Although further research is required to better investigate this recovery and to assess the suitability of this approach in a real food system, the present study showed the potential antimicrobial activity of plant derivatives, especially R. fruticosus EO, against the tyramine-producing E. faecium FC12.

11.
Biomedicines ; 10(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35625927

RESUMO

The gut microbiome has a recognized role in Non-alcoholic fatty liver disease (NAFLD) and associated comorbidities such as Type-2 diabetes and obesity. Stool transplantation has been shown to improve disease by restoring endothelial function and insulin signaling. However, more patient-friendly treatments are required. The present study aimed to test the effect of a defined bacterial consortium of nine gut commensal strains in two in vivo rodent models of Non-alcoholic steatohepatitis (NASH): a rat model of NASH and portal hypertension (PHT), and the Stelic animal (mouse) model (STAM™). In both studies the consortium was administered orally q.d. after disease induction. In the NASH rats, the consortium was administered for 2 weeks and compared to stool transplant. In the STAM™ study administration was performed for 4 weeks, and the effects compared to vehicle or Telmisartan at the stage of NASH/early fibrosis. A second group of animals was followed for another 3 weeks to assess later-stage fibrosis. In the NASH rats, an improvement in PHT and endothelial function was observed. Gut microbial compositional changes also revealed that the consortium achieved a more defined and richer replacement of the gut microbiome than stool transplantation. Moreover, liver transcriptomics suggested a beneficial modulation of pro-fibrogenic pathways. An improvement in liver fibrosis was then confirmed in the STAM™ study. In this study, the bacterial consortium improved the NAFLD activity score, consistent with a decrease in steatosis and ballooning. Serum cytokeratin-18 levels were also reduced. Therefore, administration of a specific bacterial consortium of defined composition can ameliorate NASH, PHT, and fibrosis, and delay disease progression.

12.
Front Microbiol ; 12: 651711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122365

RESUMO

Cell surface hydrophobicity (CSH) and adhesion are very important phenotypical traits for probiotics that confer them a competitive advantage for the resilience in the human gastrointestinal tract. This study was aimed to understand the effects over time of a 50 MPa hyperbaric treatment on the surface properties of Lactobacillus acidophilus 08 including CSH, autoaggregation, and in vitro adhesion (mucin layer and Caco-2 cells). Moreover, a link between the hurdle applied and the expression of genes involved in the general stress response (groEL and clpP) and adhesion processes (efTu and slpA) was evaluated. High pressure homogenization (HPH) at 50 MPa significantly increased the CSH percentage (H%), autoaggregation and in vitro adhesion on mucin of L. acidophilus 08 cells compared with the untreated cells. Moreover, the hyperbaric hurdle induced an upregulation of the stress response genes groEL and ef-TU together with a down regulation of the clpP and S-layer slpA genes. Looking at the protein profile, HPH-treatment showed an increase in the number or intensity of protein bands at high and low molecular weights.

13.
Foods ; 10(12)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34945548

RESUMO

Recently, application of high-pressure homogenization (HPH) treatments has been widely studied to improve shelf life and rheological and functional properties of vegetable and fruit juices. Another approach that has drawn the attention of researchers is the use of biocontrol cultures. Nevertheless, no data on their possible combined effect on fruit juices shelf life and functionality have been published yet. In this work, the microbial, organoleptic, and technological stability of extremely perishable carrot juice and its functionality were monitored for 12 and 7 days (stored at 4 and 10 °C, respectively) upon HPH treatment alone or in combination with a fermentation step using the biocontrol agent L. lactis LBG2. HPH treatment at 150 MPa for three passes followed by fermentation with L. lactis LBG2 extended the microbiological shelf life of the products of at least three and seven days when stored at 10 °C and 4 °C, respectively, compared to untreated or only HPH-treated samples. Moreover, the combined treatments determined a higher stability of pH and color values, and a better retention of ß-carotene and lutein throughout the shelf-life period when compared to unfermented samples. Eventually, use of combined HPH and LBG2 resulted in the production of compounds having positive sensory impact on carrot juice.

14.
Microorganisms ; 8(3)2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32244939

RESUMO

Sub-lethal high-pressure homogenization treatments applied to Lactobacillus paracasei A13 demonstrated to be a useful strategy to enhance technological and functional properties without detrimental effects on the viability of this strain. Modification of membrane fatty acid composition is reported to be the main regulatory mechanisms adopted by probiotic lactobacilli to counteract high-pressure stress. This work is aimed to clarify and understand the relationship between the modification of membrane fatty acid composition and the expression of genes involved in fatty acid biosynthesis in Lactobacillus paracasei A13, before and after the application of different sub-lethal hyperbaric treatments. Our results showed that Lactobacillus paracasei A13 activated a series of reactions aimed to control and stabilize membrane fluidity in response to high-pressure homogenization treatments. In fact, the production of cyclic fatty acids was counterbalanced by the unsaturation and elongation of fatty acids. The gene expression data indicate an up-regulation of the genes accA, accC, fabD, fabH and fabZ after high-pressure homogenization treatment at 150 and 200 MPa, and of fabK and fabZ after a treatment at 200 MPa suggesting this regulation of the genes involved in fatty acids biosynthesis as an immediate response mechanism adopted by Lactobacillus paracasei A13 to high-pressure homogenization treatments to balance the membrane fluidity. Although further studies should be performed to clarify the modulation of phospholipids and glycoproteins biosynthesis since they play a crucial role in the functional properties of the probiotic strains, this study represents an important step towards understanding the response mechanisms of Lactobacillus paracasei A13 to sub-lethal high-pressure homogenization treatments.

15.
Curr Med Chem ; 27(26): 4401-4420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30182845

RESUMO

Spices are not only just herbs used in culinary for improving the taste of dishes, they are also sources of a numerous bioactive compounds significantly beneficial for health. They have been used since ancient times because of their antimicrobial, anti-inflammatory and carminative properties. Several scientific studies have suggested their protective role against chronic diseases. In fact, their active compounds may help in arthritis, neurodegenerative disorders (Alzheimer's, Parkinson, Huntington's disease, amyotrophic lateral sclerosis, etc.), diabetes, sore muscles, gastrointestinal problems and many more. In the present study, possible roles of spices and their active components, in chronic diseases (cancer, arthritis, cardiovascular diseases, etc.) along with their mechanism of action have been reviewed.


Assuntos
Plantas Medicinais , Especiarias , Anti-Infecciosos , Doenças Cardiovasculares , Doença Crônica , Humanos
16.
Front Microbiol ; 7: 1394, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27708620

RESUMO

Spices have been used since ancient times. Although they have been employed mainly as flavoring and coloring agents, their role in food safety and preservation have also been studied in vitro and in vivo. Spices have exhibited numerous health benefits in preventing and treating a wide variety of diseases such as cancer, aging, metabolic, neurological, cardiovascular, and inflammatory diseases. The present review aims to provide a comprehensive summary of the most relevant and recent findings on spices and their active compounds in terms of targets and mode of action; in particular, their potential use in food preservation and enhancement of shelf life as a natural bioingredient.

17.
Food Chem ; 142: 285-93, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24001843

RESUMO

A mixture of novel glycopeptides from glycosylation between cold water fish skin gelatin hydrolysates and glucosamine (GlcN) via transglutaminase (TGase), as well as glycation between fish gelatin hydrolysate and GlcN were identified by their pattern of molecular distribution using MALDI-TOF-MS. Glycated/glycosylated hydrolysates showed superior bioactivity to their original hydrolysates. Alcalase-derived fish skin gelatin hydrolysate glycosylated with GlcN in the presence of TGase at 25°C (FAT25) possessed antioxidant activity when tested in a linoleic acid oxidation system, when measured according to its 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and when tested at the cellular level with human hepatocarcinoma (HepG2) cells as target cells. In addition, Alcalase-derived glycosylated hydrolysates showed specificity toward the inhibition of Escherichia coli (E. coli). The Flavourzyme-derived glycopeptides prepared at 37°C (FFC37 and FFT37) showed better DPPH scavenging activity than their native hydrolysates. The glycated Flavourzyme-derived hydrolysates were found to act as potential antimicrobial agents when incubated with E. coli and Bacillus subtilis.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Proteínas de Peixes/farmacologia , Gelatina/farmacologia , Glucosamina/análise , Peptídeos/farmacologia , Transglutaminases/química , Animais , Antibacterianos/química , Antioxidantes/química , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Proteínas de Peixes/química , Gelatina/química , Glicosilação , Células Hep G2 , Humanos , Hidrólise , Peptídeos/química
18.
Biomed Res Int ; 2014: 969143, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25177704

RESUMO

In this study, the application of eucalyptus essential oil/vapour as beverages preservative is reported. The chemical composition of eucalyptus oil was determined by gas chromatography-mass spectrometry (GC-MS) and solid phase microextraction GC-MS (SPME/GC-MS) analyses. GC-MS revealed that the major constituents were 1,8-cineole (80.5%), limonene (6.5%), α-pinene (5%), and γ-terpinene (2.9%) while SPME/GC-MS showed a relative reduction of 1,8-cineole (63.9%) and an increase of limonene (13.8%), α-pinene (8.87%), and γ-terpinene (3.98%). Antimicrobial potential of essential oil was initially determined in vitro against 8 different food spoilage yeasts by disc diffusion, disc volatilization, and microdilution method. The activity of eucalyptus vapours was significantly higher than the eucalyptus oil. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) varied from 0.56 to 4.50 mg/mL and from 1.13 to 9 mg/mL, respectively. Subsequently, the combined efficacy of essential oil and thermal treatment were used to evaluate the preservation of a mixed fruit juice in a time-dependent manner. These results suggest eucalyptus oil as a potent inhibitor of food spoilage yeasts not only in vitro but also in a real food system. Currently, this is the first report that uses eucalyptus essential oil for fruit juice preservation against food spoiling yeast.


Assuntos
Eucalyptus/química , Microbiologia de Alimentos , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Leveduras/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/farmacologia , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Leveduras/fisiologia
19.
Food Chem ; 137(1-4): 108-14, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23199997

RESUMO

The anti-yeast activity of mentha oil and vapours was evaluated against 8 food spoiling yeasts through disc diffusion, disc volatilisation and micro broth dilution method. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) varied from 0.28 to 2.25 and 1.13 to 4.5 mg/ml, respectively. Furthermore, the anti-yeast efficacy of mentha oil alone and in combination with thermal treatment was evaluated in a real food system i.e. mixed fruit juices. The samples treated with a combination of mentha oil at the MIC, ½ MIC and » MIC levels and thermal treatment enhanced the reduction viability. Chemical characterisation of mentha oil by gas chromatography-mass spectrometry (GC-MS) revealed that the dominant compounds were cis-menthone (27.43%), menthol (24.3%), trans-menthone (9.23%), limonene (5.84%), menthofuran (4.44%) and isomenthol (3.21%). Present results established the superior performance of integrated treatment over individual exposure for fruit juice preservation.


Assuntos
Antifúngicos/farmacologia , Bebidas/microbiologia , Conservantes de Alimentos/farmacologia , Mentha/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Antifúngicos/química , Bebidas/análise , Conservação de Alimentos , Conservantes de Alimentos/química , Óleos Voláteis/química , Óleos de Plantas/química , Leveduras/efeitos dos fármacos , Leveduras/crescimento & desenvolvimento
20.
Artigo em Inglês | MEDLINE | ID: mdl-23365607

RESUMO

The chemical composition of Porella arboris-vitae extracts was determined by solid phase microextraction, gas chromatography-mass spectrometry (SPME GC-MS), and 66 constituents were identified. The dominant compounds in methanol extract of P. arboris-vitae were ß-caryophyllene (14.7%), α-gurjunene (10.9%), α-selinene (10.8%), ß-elemene (5.6%), γ-muurolene (4.6%), and allo-aromadendrene (4.3%) and in ethanol extract, ß-caryophyllene (11.8%), α-selinene (9.6%), α-gurjunene (9.4%), isopentyl alcohol (8.8%), 2-hexanol (3.7%), ß-elemene (3.7%), allo-aromadendrene (3.7%), and γ-muurolene (3.3%) were the major components. In ethyl acetate extract of P. arboris-vitae, undecane (11.3%), ß-caryophyllene (8.4%), dodecane (6.4%), α-gurjunene (6%), 2-methyldecane (5.1%), hemimellitene (4.9%), and D-limonene (3.9%) were major components. The antimicrobial activity of different P. arboris-vitae extracts was evaluated against selected food spoilage microorganisms using microbroth dilution method. The Minimal Inhibitory Concentration (MIC) varied from 0.5 to 1.5 mg/mL and 1.25 to 2 mg/mL for yeast and bacterial strains, respectively. Significant morphological and ultrastructural alterations due to the effect of methanolic and ethanolic P. arboris-vitae extracts on S. Enteritidis have also been observed by scanning electron microscope and transmission electron microscope, respectively. The results provide the evidence of antimicrobial potential of P. arboris-vitae extracts and suggest its potential as natural antimicrobial agents for food preservation.

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