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1.
Artigo em Inglês | MEDLINE | ID: mdl-31294650

RESUMO

The present study examines the influence of the natural preservatives carvacrol, eugenol, trans-cinnamaldehyde and the essential oil (EO) Origanum vulgare on ochratoxin A (OTA) production and the mycelial growth of two food-related moulds, Penicillium verrucosum and Aspergillus westerdijkiae, by broth macro-dilution assay for 21 days. With the addition of ½ minimum inhibitory concentration (MIC) carvacrol, eugenol and O. vulgare EO, the mycelial dry weight of both moulds decreased significantly over the whole incubation period of 7, 14 and 21 days. Trans-cinnamaldehyde slightly stimulated the growth of A. westerdijkiae and P. verrucosum at 14 and 21 days of incubation. Growth inhibition did not accompany inhibition of OTA production. Although the growth of both moulds was inhibited after the addition of ½ MIC carvacrol, eugenol and O. vulgare EO, the OTA production of the strong mycotoxin producer A. westerdijkiae was stimulated. Only trans-cinnamaldehyde inhibited the production of OTA with the addition of ½ MIC. P. verrucosum produced significantly less OTA than A. westerdijkiae, and its mycotoxin production was almost completely inhibited by the addition of ½ MIC of the natural preservatives.


Assuntos
Aspergillus/efeitos dos fármacos , Microbiologia de Alimentos , Conservantes de Alimentos/farmacologia , Micélio/efeitos dos fármacos , Ocratoxinas/biossíntese , Penicillium/efeitos dos fármacos , Acroleína/análogos & derivados , Acroleína/química , Acroleína/farmacologia , Aspergillus/química , Eugenol/química , Eugenol/farmacologia , Conservantes de Alimentos/química , Monoterpenos/química , Monoterpenos/farmacologia , Micélio/crescimento & desenvolvimento , Ocratoxinas/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Penicillium/química
2.
Food Chem ; 298: 125080, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260985

RESUMO

Propolis extract was investigated as potential substitute for sorbate in orangeade. Extract was prepared by using aqueous solution of hydroxypropyl-beta-cyclodextrins. Propolis extract was incorporated in non-carbonated orange soft drinks and its antioxidant activity, microbiological stability and color changes were estimated and compared to those of orangeade containing potassium sorbate. l-Ascorbic acid (AsA) degradation at concentrations 0.13 and 1.3% w/w was investigated in the presence of propolis during storage using High Performance Liquid Chromatography-Ion Exclusion Column (HPLC-IEC). The results indicate that the rate of degradation decreased with an increase in ascorbic acid concentration, while addition of propolis affected the degradation rate of samples containing a high AsA concentration. The antifungal effect of propolis extract, potassium sorbate and their combination was assayed. Results showed the inhibition of Aspergillus spp. and B. bruxellensis inhibited in low combined concentrations antimicrobials, while Aspergillus spp. and T. macrosporus were inhibited at 450 mg/g propolis extract.


Assuntos
Bebidas , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Própole/química , Anti-Infecciosos , Antifúngicos/farmacologia , Antioxidantes/química , Ácido Ascórbico/análise , Ácido Ascórbico/química , Aspergillus/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Cor , Microbiologia de Alimentos , Extratos Vegetais/química , Própole/farmacologia , Ácido Sórbico/farmacologia
3.
Carbohydr Polym ; 219: 334-343, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151533

RESUMO

The objective of this work was to investigate the effect of the addition of carboxymethyl chitosan on the structural properties and antilisterial activity of nisin-incorporated chitosan films. Chitosan and carboxymethyl chitosan solutions were prepared with different mass ratios and bacteriocin nisin was added (0, 1000 and 6000 IU/ml). Filmogenic solutions were cast, dried and their physico-chemical and antimicrobial properties were investigated. For the same chitosan/carboxymethyl chitosan mass ratio, the addition of NIS at 6000 IU/ml led to changes in the macro- and microstructure, as well as in physico-chemical properties of films. On the other hand, carboxymethyl chitosan had a plasticizing effect and enhanced the distribution of the bacteriocin within the biopolymer matrix. Moreover, nisin-incorporated blend films of chitosan and carboxymethyl chitosan were more effective against Listeria monocytogenes than their pure chitosan counterparts. This study showed that different formulations of nisin-incorporated composite films of chitosan and carboxymethyl chitosan may provide options for developing bioactive packaging to improve food safety.


Assuntos
Antibacterianos , Quitosana/análogos & derivados , Conservantes de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Nisina , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Microbiologia de Alimentos , Embalagem de Alimentos , Conservação de Alimentos , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Nisina/química , Nisina/farmacologia
4.
J Microbiol Biotechnol ; 29(7): 1033-1042, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216789

RESUMO

Bacillus velezensis BS2 was isolated from meongge (common sea squirt) jeotgal, a Korean fermented seafood, and produces a bacteriocin, BacBS2, which strongly inhibits Listeria monocytogenes and Bacillus cereus. BacBS2 was partially purified by Q-Sepharose column chromatography after ammonium sulfate precipitation of the culture supernatant, then further purified by Sephadex G-50 column chromatography. Partially purified BacBS2 was estimated to be 6.5 kDa in size by Tricine-SDS PAGE and activity detection by gel-overlay. Enzyme treatment and FT-IR spectrum of partially purified BacBS2 confirmed its proteinaceous nature. BacBS2 was fully stable at pH 4-9, and half of activity was retained at pH 1-3. Full activity was retained after exposure to 80°C for 15 min, but half of the activity was retained upon exposure to 90°C for 15 min or 100°C for 10 min. BacBS2 inhibited L. monocytogenes by bactericidal mode of action. B. velezensis BS2 and its BacBS2 seem useful as biopreservatives for fermented foods such as jeotgal.


Assuntos
Antibacterianos/metabolismo , Bacillus/metabolismo , Bacteriocinas/isolamento & purificação , Bacteriocinas/metabolismo , Alimentos Fermentados/microbiologia , Conservantes de Alimentos/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antibiose , Bacillus/crescimento & desenvolvimento , Bacillus/fisiologia , Bacillus cereus/efeitos dos fármacos , Bacteriocinas/química , Bacteriocinas/farmacologia , Meios de Cultura , Conservantes de Alimentos/química , Conservantes de Alimentos/isolamento & purificação , Conservantes de Alimentos/farmacologia , Temperatura Alta , Concentração de Íons de Hidrogênio , Listeria monocytogenes/efeitos dos fármacos , Peso Molecular , Estabilidade Proteica
5.
Food Chem ; 293: 491-498, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151640

RESUMO

Synthetic food preservatives like sodium acetate (SA), sodium benzoate (SB), potassium sorbate (PS) and Butyl paraben (BP) have been widely used in food and pharmacy industries. One of the toxicological aspects of food additives is evaluation of their interaction with serum proteins such as albumin. These additives interaction with human serum albumin (HSA) can exert considerable effect on the absorption, distribution, metabolism and toxicity of chemical compounds. It should be noticed that the aforementioned food preservatives intake increase mainly in the presence of glucose may lead to complex formation of SA, SB, PS and BP with HSA and accelerate the development of variety disease such as cancer, diabetes, multiple sclerosis, brain damage, nausea and cardiac disease. Therefore, to understand the mechanisms of aforementioned food additives interaction and conformational changes of proteins, we aim to review various studies that investigated albumin interaction with these additives using several procedures.


Assuntos
Conservantes de Alimentos/química , Albumina Sérica/química , Citocinas/genética , Citocinas/metabolismo , Dano ao DNA/efeitos dos fármacos , Conservantes de Alimentos/toxicidade , Humanos , Estresse Oxidativo/efeitos dos fármacos , Parabenos/química , Parabenos/toxicidade , Acetato de Sódio/química , Acetato de Sódio/toxicidade , Benzoato de Sódio/química , Benzoato de Sódio/toxicidade , Ácido Sórbico/química , Ácido Sórbico/toxicidade
6.
J Sci Food Agric ; 99(13): 6032-6041, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31226218

RESUMO

BACKGROUND: In order to inhibit microorganisms and improve storage quality of fresh-cut cucumber, fresh-cut cucumber was treated by carbon dots (CDs) from kelp/chitosan (CH) coating solution with CD concentrations of 0%, 1.5%, 3% and 4.5% and then packaged as well as stored at 4 °C for 15 days. The effect of CDs/CH coating on microorganisms and the quality of modified-atmosphere-packaged fresh-cut cucumber during storage were investigated. RESULTS: The CDs was monodispersed spherical morphology with size distribution of 0.54-0.83 nm. Interaction of CDs and CH had the generation of strong hydrogen bond. Inhibition zone diameters of CDs/CH coating against Staphylococcus aureus and Escherichia coli were enhanced with the increase of CD concentrations. Moreover, CDs/CH coating inhibited the growth of total number of colonies, mold, and yeast in modified-atmosphere-packaged fresh-cut cucumber during storage. A coating of 4.5% CDs/CH effectively reduced the losses of weight, firmness, and total soluble solids, the degradation of ascorbic acid content and flavor, and inhibited peroxidases activity, as well as decreased water mobility in fresh-cut cucumber during storage. CONCLUSION: The results indicated that a CDs/CH coating was helpful for inhibiting microorganisms and improving storage quality, and could be an effective method to prolong shelf life of fresh-cut cucumber. © 2019 Society of Chemical Industry.


Assuntos
Carbono/farmacologia , Quitosana/farmacologia , Cucumis sativus/efeitos dos fármacos , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Carbono/química , Quitosana/química , Cucumis sativus/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Embalagem de Alimentos , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/química , Armazenamento de Alimentos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Paladar
7.
J Sci Food Agric ; 99(13): 6060-6065, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31226223

RESUMO

BACKGROUND: Chestnuts are gluten-free, low-fat, cholesterol-free products. Postharvest decay reduces chestnut shelf life and can cause severe economic losses. In this study we investigated the effect of ozone (O3 ) gaseous treatment on chestnut rot caused by Gnomoniopsis castanea and the quality parameters of chestnuts. RESULTS: The results showed that ozone treatment (150 ppb during the day, and 300 ppb during the night) reduced the decay of chestnuts and had a fungistatic effect on isolates of G. castanea. The exposure of chestnuts to ozone did not alter weight losses, sugar content and titratable acidity. The concentration of total phenolics decreased during the storage period, both for treated and untreated nuts. However, after 150 days of treatment the polyphenol content of the chestnuts exposed to ozone was significantly higher than in control nuts. CONCLUSIONS: Our results suggested that ozone is an appropriate and economical tool to maximize the quality of chestnut shelf life, enabling it to be stored for long periods. © 2019 Society of Chemical Industry.


Assuntos
Fagaceae/química , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Nozes/química , Ozônio/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Carboidratos/química , Fagaceae/microbiologia , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/química , Armazenamento de Alimentos , Nozes/microbiologia , Ozônio/química , Fenóis/química , Controle de Qualidade
8.
Int J Mol Sci ; 20(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064114

RESUMO

In order to extend the shelf life of the fruit, improve appearance, and to keep all nutrition properties of the plum from diminishing, edible coatings comprised of wheat starch and wheat starch-whey protein isolate (in ratio 80/20) were created. Stand-alone films were produced to assess properties which helped to understand the phenomena occurring on the surface level of coated plums. The properties of coatings based on starch are similar to starch coatings containing oil because the natural epicuticular wax layer of plums merges with coating materials. Adding oil doubled the contact angle value and the dispersive component of the surface tension. The workings of adhesion and cohesion, spreading coefficient, water absorption, water content, and solubility in water of the films decreased. Similar processes were observed on the fruits' surface. In appearance, the coating process is similar to polishing the plum surface for removing crystalline wax. The color parameters of coated fruits did not significantly change. Newly formed bonds or interactions established between starch, whey proteins, water, glycerol, and oil are displayed by Fourier transform infrared (FTIR) analysis. This work revealed how the interactions between the epicuticular wax on the fruit's surface and the hydrocolloid-based coatings affect the efficiency of the coatings.


Assuntos
Conservantes de Alimentos/química , Frutas/efeitos dos fármacos , Prunus domestica/efeitos dos fármacos , Conservantes de Alimentos/farmacologia , Frutas/química , Glicerol/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Tensão Superficial , Ceras/química , Molhabilidade , Proteínas do Soro do Leite/química
9.
J Food Sci ; 84(6): 1288-1296, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31120570

RESUMO

The preservation effects of tartary buckwheat extract (T) and chitosan (C) coatings on the physicochemical (pH value, thiobarbituric acid value, Peroxide value (PV), total volatile basic nitrogen (TVB-N), K value, surface color and the texture profiles), bacteriological (total viable counts (TVC) and psychrotrophic bacteria counts (PBC)), and sensory characteristics of tilapia (Oreochromis niloticus) fillets storage at 0 °C for 18 days were evaluated. The fillets coated with 0.5% T + 1.0% C, 1.0% T + 1.0% C and 1.5% T + 1.0% C maintained better quality and had longer shelf life with respect to samples coated with chitosan alone and the control. Base on the limit values of TVB-N, K value, TVC and sensory preference scores, the shelf life of control fillets was 6 days. By contrast, shelf life of 9 days for 0.5% T + 1.0% C-coated fillets, 12 days for 1.0% T + 1.0% C treated-fillets, and 15 days for 1.5% T + 1.0% C-treated fillets were obtained. Therefore, TBE combined with chitosan coatings have the potential to extend the shelf life of tilapia fillets during storage at 0 °C. PRACTICAL APPLICATION: This study provides basic theory regarding the application of TBE to fish preservation. The edible coating of TBE combined with chitosan has potential use in developing activity food preservation coating.


Assuntos
Quitosana/química , Fagopyrum/química , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Extratos Vegetais/química , Animais , Ciclídeos , Cor , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Humanos , Paladar
10.
Food Microbiol ; 82: 445-454, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027804

RESUMO

This study aimed to investigate effects of aqueous pomegranate peel extract (APPE) and ethanolic pomegranate peel extract (EPPE) on microbiota and changes in quality of bighead carp (Aristichthys nobilis) fillets stored at 4 °C. The results showed that pomegranate peel extract (PPE, which includes both APPE and EPPE) retarded the deterioration of sensory quality and flesh color, inhibited the growth of spoilage bacteria, and attenuated the production of biogenic amines, total volatile basic nitrogen (TVB-N), and the degradation of ATP-related compounds. Moreover, EPPE performed better in color attributes and biogenic amines, but APPE was more effective in retarding the increase of TVB-N and K-value. High-throughput sequencing results showed that microbial composition of all samples became less diverse as storage time increased. For the control group, Acinetobacter was predominant in the middle-period of storage, while Pseudomonas, Aeromonas, and Shewanella became predominant at the end of storage. Additionally, PPE decreased the relative abundance of Acinetobacter in the middle-period of storage, and thus changed the microbial composition. Based on our assessments of quality and microbial analysis, PPE prolonged the shelf-life of bighead carp fillets for about 2 days, and it has the potential to become a promising preservative in aquatic products.


Assuntos
Microbiologia de Alimentos , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Microbiota/efeitos dos fármacos , Extratos Vegetais/farmacologia , Punicaceae/química , Alimentos Marinhos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Aminas Biogênicas/análise , Carpas , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Nitrogênio/análise , Extratos Vegetais/química , Refrigeração , Alimentos Marinhos/análise , Alimentos Marinhos/microbiologia
11.
Food Microbiol ; 82: 504-514, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027812

RESUMO

As a result of the rapidly growing human population, reducing post-harvest crop losses of cereals due to microbial pests has major importance. Plant defensins have the potential to fulfil these demands, being highly specific and efficient antimicrobial agents. Hence, this study aimed to extract and characterise a peptide from cowpea seeds and investigate its antifungal performance. After extraction and partial purification, N-terminal sequencing was used to identify the primary peptide in the extract as cowpea-thionin II. Antifungal activity in vitro was found against Fusarium culmorum (MIC = 50 µg/mL), but Aspergillus niger and Penecillium expansum showed an MIC > 500 µg/mL. The extract was resistant against heat treatment (100 °C, 15 min) but lost its antifungal activity in presence of cations (Na+, K+, Ca2+ and Mg2+, respectively). Membrane permeabilization of fungal hyphae was evident at 25 µg/mL, while induction of oxidative stress only had minor contribution to the antifungal performance. The extract did not induce haemolysis at all concentrations tested (up to 200 µg/mL). Finally, it was successfully used to protect stored wheat grains from fungal spoilage (determined via ergosterol content) when applied at 100 µg/mL. In conclusion, the defensin Cp-thionin II showed the potential for future application as food bio-preservative.


Assuntos
Antifúngicos/farmacologia , Conservantes de Alimentos/farmacologia , Fungos/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Tioninas/farmacologia , Vigna/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Cátions , Permeabilidade da Membrana Celular/efeitos dos fármacos , Defensinas/química , Defensinas/isolamento & purificação , Defensinas/farmacologia , Grão Comestível/microbiologia , Ergosterol/análise , Ergosterol/metabolismo , Microbiologia de Alimentos , Conservantes de Alimentos/química , Conservantes de Alimentos/isolamento & purificação , Fungos/metabolismo , Fungos/fisiologia , Temperatura Alta , Hifas/efeitos dos fármacos , Hifas/metabolismo , Hifas/fisiologia , Testes de Sensibilidade Microbiana , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Estabilidade Proteica , Sementes/química , Tioninas/química , Tioninas/isolamento & purificação
12.
Int J Food Microbiol ; 300: 31-42, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31005779

RESUMO

Starch nanocrystal (S-NC) was produced after sulfuric acid hydrolysis of potato starch granules and then characterized by laser diffraction particle size analyzer, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Response surface methodology (RSM) was applied to optimize S-NC (2-10%) concentration, sour lemon peel extract (SLPE, 2.5-12.5%) amount, mixing temperature (M-TE, 25-65 °C) and mixing time (M-TI,15-75 min) in the preparation of bioactive coating solutions to develop the high-quality chicken fillets during the cold-storage. The optimized conditions for achieving the highest DPPH inhibition percentage (89.14%), antibacterial activity (Staphylococcus aureus, 3.58-mm; Escherichia coli, 3.14-mm; Listeria monocytogenes, 2.31-mm and Salmonella enterica, 2.24-mm) and lightness value (77.82) and the lowest redness (6.69), yellowness (13.21) values and viscosity (27.5 mPa.s) were 4.0% S-NC, 5.62% SLPE, 51.17 °C M-TE and 43.29 min M-TI. Spraying the optimal coating solution on chicken fillets led to a significant improvement in their physicochemical, textural and sensory characteristics compared to the control during 12-day cold-storage.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Citrus/química , Microbiologia de Alimentos/métodos , Conservantes de Alimentos/normas , Amido/química , Animais , Antibacterianos/química , Galinhas , Escherichia coli/efeitos dos fármacos , Conservantes de Alimentos/química , Frutas/química , Listeria monocytogenes/efeitos dos fármacos , Nanopartículas , Salmonella enterica/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Paladar , Ultrassom
13.
Food Funct ; 10(3): 1352-1363, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30834918

RESUMO

The aim of this work was to optimize the conditions for the extraction of phenolic compounds (PC) from male chestnut flowers using heat-assisted extraction in developing extracts rich in PC for potential industrial application as a natural ingredient. The study conditions of time (t), temperature (T), solvent (S, water-ethanol mixtures) and solid-to-liquid ratio (S/L) were optimized. The responses used were obtained from the quantification of the fourteen major individual PC identified by HPLC-DAD-ESI/MS (seven hydrolysable tannins and seven flavonoids). The recovery of hydrolysable tannins was higher than that of flavonoids, with trigalloyl-HHDP-glucoside being the major one. The conditions that maximized the PC content were t = 20.0 ± 37.7 min, T = 25.0 ± 5.7 °C, S = 0.0 ± 8.7% ethanol and S/L = 82.8 g L-1, producing an extract with 86.5 mg PC g-1 of extract. The results highlight the potential of valorising chestnut flower agro-residues as a productive source of PC for the development of bio-based ingredients for food/pharmaceutical/cosmeceutical industrial applications able to compete with synthetic compounds.


Assuntos
Fracionamento Químico , Flores/química , Conservantes de Alimentos/farmacologia , Hippocastanaceae/química , Extratos Vegetais/farmacologia , Conservantes de Alimentos/química , Temperatura Alta , Extratos Vegetais/química
14.
J Sci Food Agric ; 99(10): 4731-4738, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30924936

RESUMO

BACKGROUND: Sakacin-A due to its specific antimicrobial activity may represent a good candidate to develop active packaging solutions for food items supporting Listeria growth. In the present study a protein extract containing the bacteriocin sakacin-A, produced by Lactobacillus sakei Lb 706 in a low-cost culture medium containing deproteinized cheese whey, was adsorbed onto cellulose nanofibers (CNFs) to obtain an active material to be used as a mat (or a separator) in direct contact with foods. RESULTS: The applied fermentation conditions allowed 4.51 g L-1 of freeze-dried protein extract to be obtained, characterized by an antimicrobial activity of near 16 700 AU g-1 , that was used for the preparation of the active material by casting. The active material was then characterized by infrared spectra and thermogravimetric analyses. Antimicrobial trials were carried out in vitro using Listeria innocua as indicator strain; results were also confirmed in vivo, employing smoked salmon fillets intentionally inoculated with Listeria innocua: its final population was reduced to about 2.5-3 Log cycles after 28 days of storage at 6 °C in presence of sakacin-A, compared with negative control mats produced without the bacteriocin extract. CONCLUSION: This study demonstrates the possibility of producing an antimicrobial active material containing sakacin-A absorbed onto CNFs to decrease Listeria population in smoked salmon, a ready-to eat-food product. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antibacterianos/química , Bacteriocinas/química , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Nanofibras/química , Animais , Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Celulose/química , Fast Foods/análise , Fast Foods/microbiologia , Produtos Pesqueiros/microbiologia , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/farmacologia , Listeria/crescimento & desenvolvimento , Salmão/microbiologia
15.
Food Chem ; 287: 61-67, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30857719

RESUMO

Propolis has demonstrated potential use as food preservative but it presents strong and unpleasant flavor that alters the sensory characteristics foods. A nanoemulsion was proposed to carry the Brazilian propolis extracts for use as natural food preservative. Antimicrobial and antioxidant activities and chemical constituents of the extracts were investigated. The latter were made by sequential extraction using different solvents (hexane, ethyl acetate and ethanol). Antimicrobial activity was evaluated by agar diffusion and microdilution methods and antioxidant activity by DPPH and ABTS assays. Extracts showed antibacterial and antioxidant activity, highlighting the ethanolic which contained artepillin-C, kaempferide, drupanin and p-coumaric acid as main compounds by LC-MS analysis. The nanoemulsion developed by phase inversion method was characterized and stable under thermal-stress and centrifugation conditions. Biological properties evaluated were effectively maintained by the formulation. It was concluded that the nanoemulsion can be used as a food preservative, preventing degradation and masking the propolis off-flavor.


Assuntos
Anti-Infecciosos , Antioxidantes , Conservantes de Alimentos , Própole , Anti-Infecciosos/análise , Anti-Infecciosos/química , Antioxidantes/análise , Antioxidantes/química , Emulsões/análise , Emulsões/química , Conservantes de Alimentos/análise , Conservantes de Alimentos/química , Nanotecnologia , Própole/análise , Própole/química
16.
Int J Mol Sci ; 20(5)2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30857155

RESUMO

Whey protein nanofibrils (WPNFs) can be used in edible films and coatings (EFCs) because of its favorable functional properties, which rely on its well-ordered ß-sheet structures, high hydrophobicity, homogeneous structure, and antioxidant activity. In the present study, WPNF-based edible coatings with glycerol (Gly) as plastic and titanium dioxide nanotubes (TNTs) as antimicrobial agents were studied. TNTs not only showed greater antibacterial activity than titanium dioxide nanoparticles (TNPs), but also increased interactions with WPNFs. The WPNF/TNT film had a smooth and continuous surface and was homogeneous with good mechanical properties. WPNF/TNT edible coatings (ECs) can help improve lipid peroxidation and antioxidant activity, limit microbial growth, reduce weight loss, and extend the shelf life of chilled beef. Given that the WPNF/TNT film components are low cost and show high antioxidant and antimicrobial activity, these optimized films have potential applications for various food products, including raw and chilled meat.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Carne Vermelha/análise , Titânio/química , Proteínas do Soro do Leite/química , Animais , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Bovinos , Temperatura Baixa , Conservantes de Alimentos/farmacologia , Qualidade dos Alimentos , Nanotubos/química , Nanotubos/ultraestrutura , Carne Vermelha/microbiologia , Titânio/farmacologia , Proteínas do Soro do Leite/farmacologia
17.
J Food Sci ; 84(4): 832-841, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30912858

RESUMO

The aim of the study was to control the release of peppermint oil (700 µL/L) by coating activated carbon (AC) contained in sachets with different solutions (tapioca starch, corn starch, gelatine, carnauba, paraffin, and mixed carnauba-paraffin) for inhibiting the growth of Aspergillus flavus on brown rice (BR). Paraffin-coated AC with adsorbed peppermint oil was then applied to extend the shelf life of BR during long-term storage (60 days) at 30 ± 2 °C. The mechanism of peppermint oil vapor release in this system was also studied using GC-MS. The result revealed that paraffin-coated AC with adsorbed peppermint oil present in sachets showed the highest antifungal activity against A. flavus growing on the surface of BR. In addition, paraffin-coated AC with adsorbed peppermint oil could prolong the shelf life of BR from 10 days (control) to at least 60 days under tropical climatic conditions. Moreover, storage of BR in the presence of sachets containing paraffin-coated AC with adsorbed peppermint oil at a concentration of 700 µL/L revealed no significant effects on major rice quality-related factors, such as moisture content, color, water uptake percentage, and gelatinization temperature. Peppermint oil component analysis by GC-MS indicated that paraffin could trap some minor components of peppermint oil and allow the major components such as menthone, menthol, and alpha-pinene, which are compounds that play an important role in mold growth inhibition, to be exposed to air. Thus, this research demonstrated the potential of paraffin-coated AC containing adsorbed peppermint oil for controlling the growth of molds during prolonged rice storage. PRACTICAL APPLICATION: Paraffin-coated activated carbon with adsorbed peppermint oil has the potential to be commercially applied to brown rice grains for facilitating long-term storage. This technique is beneficial for avoiding the occurrence of negative sensorial factors when peppermint oil vapors are used. This process is interesting and easy to apply during large-scale implementation of a rice storage system.


Assuntos
Aspergillus flavus/efeitos dos fármacos , Conservantes de Alimentos/química , Oryza/microbiologia , Parafina/química , Óleos Vegetais/química
18.
Food Chem ; 285: 275-281, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797345

RESUMO

The exposure of fatty products to environmental light can trigger lipid oxidation in food through a sensitized-photooxidation process, which involves the participation of the species singlet oxygen (O2(1Δg)). Therefore, preservation of food quality represents a subject of great economic interest to the food industry. In this sense, the phenolic compounds are natural antioxidants widely used in food industry. In this contribution we studied the interactions of phenolic derivatives (Phd), tyrosol and tyrosol derived isomers, with O2(1Δg) and their possible protective effect against the oxidative degradation of unsaturated fatty acids and amino acids. Besides, a potential synergistic interaction between Phd and antioxidants used in food industry were investigated. Phd substrates showed properties as antioxidant additives due to their high ability deactivating O2(1Δg) through a physical process and synergistic effect in the presence of commercial antioxidants. Phd presented an antioxidant protective effect toward O2(1Δg)-mediated degradation of methyl linoleate and tryptophan.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Álcool Feniletílico/análogos & derivados , Sinergismo Farmacológico , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Concentração de Íons de Hidrogênio , Isomerismo , Ácidos Linoleicos/química , Oxirredução , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Oxigênio Singlete , Triptofano/química , Raios Ultravioleta
19.
J Sci Food Agric ; 99(7): 3467-3474, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30623439

RESUMO

BACKGROUND: The marketability of banana is limited by the rapid rate of ripening. However, the traditional post-harvest technologies may not be desirable. The aim of this study was to investigate the potential of a reusable material for the food preservation industry. RESULTS: The nanocomposite-based palladium (Pd)-modified zeolite (Pd/zeolite) was prepared by impregnating Pd into zeolite. Pd/zeolite had a Brunauer-Emmett-Teller dinitrogen specific surface area of 475 m2 g-1 with crystal structure similar to Y-zeolite. Transmission electron microscopy images showed the dispersion of Pd particles over the multi-pore zeolite support. Pd/zeolite uniquely acted as an adsorbent and a catalyst and was able to remove ethylene even after reaching breakthrough point. To prove Pd/zeolite is reusable, a 99 ± 0.8% ethylene removal efficiency still remained even after five consecutive cycles with repeated use of Pd/zeolite. The presence of Pd/zeolite significantly decreased the ethylene concentration during 18 days of storage at 20 ± 2 °C. CONCLUSIONS: Pd/zeolite could delay the ripening of banana and improve its firmness and the peel color significantly. Findings indicated that the as-prepared Pd/zeolite is an effective adsorbent/catalyst with high potential for practical application in ethylene removal, especially for the post-harvest period. © 2019 Society of Chemical Industry.


Assuntos
Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Musa/química , Paládio/farmacologia , Zeolitas/farmacologia , Catálise , Etilenos/análise , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/química , Frutas/química , Paládio/química , Zeolitas/química
20.
Mol Microbiol ; 111(3): 717-731, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30537404

RESUMO

The emergence and dissemination of antibiotic resistant bacteria is a major medical challenge. Lantibiotics are highly modified bacterially produced antimicrobial peptides that have attracted considerable interest as alternatives or adjuncts to existing antibiotics. Nisin, the most widely studied and commercially exploited lantibiotic, exhibits high efficacy against many pathogens. However, some clinically relevant bacteria express highly specific membrane-associated nisin resistance proteins. One notable example is the nisin resistance protein that acts by cleaving the peptide bond between ring E and the adjacent serine 29, resulting in a truncated peptide with significantly less activity. We utilised a complete bank of bioengineered nisin (nisin A) producers in which the serine 29 residue has been replaced with every alternative amino acid. The nisin A S29P derivative was found to be as active as nisin A against a variety of bacterial targets but, crucially, exhibited a 20-fold increase in specific activity against a strain expressing the nisin resistance protein. Another derivative, nisin PV, exhibited similar properties but was much less prone to oxidation. This version of nisin with enhanced resistance to specific resistance mechanisms could prove useful in the fight against antibiotic resistant pathogens.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bioengenharia/métodos , Nisina/química , Nisina/farmacologia , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Lipoproteínas/metabolismo , Proteínas de Membrana/metabolismo , Testes de Sensibilidade Microbiana , Nisina/genética
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