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1.
Int J Biol Macromol ; 268(Pt 1): 131727, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38649073

RESUMEN

Biodegradable edible films for sour cream packaging were developed based on chitosan (CS), hydroxyethyl cellulose (HEC), Olive leaf extract (OE), and titanium dioxide nanoparticles (TiO2-NPs). The prepared CS/HEC/TiO2-OE bionanocomposite films were evaluated for their antimicrobial and antioxidant activities as well as using FT-IR, mechanical, permeability, and contact angle. The effect of developed films on the lipid oxidation, microbiological load, and chemical properties of sour cream was investigated. The fabricated films had an antimicrobial impact against all tested strains. The film containing 8 % OE showed effective protection against fat oxidation, with a peroxide value of 3.21 meq O2/kg, a para-anisidine value 5.40, and free fatty acids of 0.82 mg KOH/kg. The films with OE 4 % and 8 % have a good effect on the microbiological load of sour cream for 90 days. These films did not influence the chemical composition of sour cream and therefore can be used in this sort of dairy product.


Asunto(s)
Celulosa , Quitosano , Películas Comestibles , Embalaje de Alimentos , Olea , Extractos Vegetales , Hojas de la Planta , Titanio , Quitosano/química , Quitosano/farmacología , Titanio/química , Celulosa/química , Celulosa/análogos & derivados , Hojas de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Olea/química , Embalaje de Alimentos/métodos , Antioxidantes/farmacología , Antioxidantes/química , Permeabilidad , Antiinfecciosos/farmacología , Antiinfecciosos/química , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas/química
2.
Vet Sci ; 10(10)2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37888581

RESUMEN

Milk production continues to be the main source of income for dairy producers, and mastitis continues to be the major health challenge for dairy cows worldwide. The objective of the current study was to describe the different management practices implemented in Egyptian dairies, which may influence mastitis and improve milk quality. An in-person survey was completed with herd managers and owners of 20 Egyptian dairies selected using a stratified random sample from four of Egypt's milk sheds. The questionnaire included 80 questions that inquired about herd demographics, mastitis status and control, milking practices, and management practices of the study dairies. Statistical analyses included descriptive statistics, multiple factor analysis (MFA), and hierarchical clustering to identify the important principal components and different dairy clusters. Of the surveyed herds, 69.50% had less than 500 lactating cows, with Holstein as the main cow breed. The reported average milk production on the study herds was 31.1 (SE ± 1.10) Kg/cow/day. Housing of lactating, dry, and close-up cows was in open lots. The majority of the dairies milked cows were three times per day (90.63%), the remaining milked cows four (5.00%) or a mix of four and three times per day. Furthermore, herringbone parlor design was the most common parlor design (66.79%) in the study dairies. The most common disinfectants used for both pre- and post-milking teat dip were iodine-based, 90.0% and 95.0%, respectively, while 52.16% of the dairies reported that their milkers wore gloves during milking. The reported mean annual percentage of mastitis was 52.3%, as a percent of the milking herd. The study dairies reported the inspection of udder health through either visual inspection (95.00%), udder hygiene score (86.88%), teat end score (71.88%), and/or using CMT (54.91%). Contagious mastitis pathogens were reported in 45.2% of the study herds. More than 50% of the study herds relied on importing pregnant cows or pregnant heifers as replacements. Multiple factor analysis identified 20 questions and represented 5 components of variability related to mastitis on dairies. The current survey of Egyptian dairies described the herd demographics and different management practices related to mastitis control and prevention. All the study dairies relied on the blanket intramammary antimicrobial drugs at dry off when current research elsewhere has identified selective dry cow therapy as an integral component of antimicrobial stewardship on dairies. Further research is required to identify the association between different management factors and the occurrence of mastitis.

3.
Sci Rep ; 13(1): 10977, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37414826

RESUMEN

We evaluated the anti-cariogenic effect of an experimental synbiotic compound containing probiotic Lacticaseibacillus rhamnosus (NRRL B-442)-based jelly candy supplemented with natural prebiotic grape seed extract (GSE) in a nanoemulsion formula on the colonization and establishment of Streptococcus mutans (ATCC 25175) and Actinomyces viscosus (ATTCC 19246) biofilms through counting colony forming units, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). We were then analysing the remineralizing effect of synbiotic jelly candy on human enamel surface lesions using Vickers microhardness testers, atomic force microscopy (AFM), SEM, energy-dispersive X-ray spectroscopy (EDAX), and confocal laser scanning microscopy (CLSM) at three stages (sound, after demineralization, and after pH cycling). We found after 21 days of treatment of the pH-cycled enamel discs with jelly candy for 10 min twice daily, a 68% decrease in S. mutans colony formation, reducing biofilm development, trapping S. mutans visualized in jelly candy under SEM examination, and significantly altering the morphological structure of these bacteria under TEM analysis. For remineralization measurements, statistically significant differences in microhardness integrated mineral loss, and lesion depth through CLSM between demineralization and treatment stages. These findings provide an effective anti-cariogenic synbiotic compound of grape seed extract and probiotic jelly candy with potential remineralizing activity.


Asunto(s)
Caries Dental , Extracto de Semillas de Uva , Probióticos , Humanos , Extracto de Semillas de Uva/farmacología , Prebióticos , Streptococcus mutans , Probióticos/farmacología , Dulces , Biopelículas , Remineralización Dental/métodos , Caries Dental/prevención & control
4.
Int J Biol Macromol ; 242(Pt 1): 124782, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37169048

RESUMEN

As a replacement for saturated fats, bigel butter spread (BgBs) based on sesame oleogel and alginate hydrogel was developed. Morphology, oxidative stability, microbiological, chemical, and sensory analysis were assessed. The results demonstrated that unsaturated fatty acids were higher in cinnamon (73.87 %) than in plain (71.57 %) BgBs. The peroxide value was higher in plain (5.25 meqO2/kg) than in cinnamon BgBs (4.29 meqO2/kg). Cinnamon BgBs had 44.44 % more antioxidant activity compared to plain BgBs (40.20 %). Moreover, BgBs products kept their probiotic counts at >7 log cycles. The cinnamon BgBs had a lower microbial load than plain BgBs. The chemical composition of the BgBs products did not change significantly. But the pH values slightly dropped with the storage time. The sensory evaluation of plain and cinnamon BgBs did not significantly differ from one another. However, the period of storage and the addition of the cinnamon oil significantly affected the flavor ratings.


Asunto(s)
Probióticos , Sesamum , Alginatos , Hidrogeles/química , Mantequilla
5.
Sci Rep ; 12(1): 14751, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042364

RESUMEN

Green synthesis selenium nanorods (Se-NRs) were produced based on Aloe vera leaf extract. The size, morphology, antimicrobial, and activation of Se-NRs for probiotics were analyzed. The Se-NRS was stable with a diameter of 12 and 40 nm, had an antimicrobial effect, and improved probiotics counts. The microcapsules loaded with Green Se-NRS (0, 0.05 or 0.1 mg/100 ml) and probiotics (Bifidobacterium lactis and Lactobacillus rhamnosus) were designated with efficiency between 95.25 and 97.27% and irregular shapes. Microcapsules were saved probiotics against gastrointestinal juices. The microcapsules were showed a minor inhibition effect against the cell line. Also, microcapsules integrated into stirred yogurt and exanimated for microbiology, chemically, and sensory for 30 days. The probiotics counts, acidity, total solids, and ash values of samples were increased during storage periods without affecting fat and protein contents. The overall acceptability of yogurt with microcapsules containing probiotics and Se-NRs was high without change in body, odor, color, and appearance.


Asunto(s)
Antiinfecciosos , Nanotubos , Probióticos , Selenio , Cápsulas , Yogur/microbiología
6.
Toxicol Mech Methods ; 31(9): 699-710, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34376109

RESUMEN

The purpose of this study was designed to evaluate the protective effect of probiotics fortified with Aloe vera pulp nanoemulsion on ethanol-induced gastric ulcer (GU). Freshly harvested Aloe vera pulp nanoemulsion was prepared and subsequently inoculated with 2% of the activated yogurt starter culture of Streptococcus thermophilus and Lactobacillus delbreukii subsp. bulgaricus (1:1). Chemical composition and physicochemical characterization of yogurt and the Aloe vera pulp nanoemulsion were assessed. GU was induced by ethanol. Rats were randomly assigned into control, GU, and four prophylactic groups including probiotics fortified with Aloe vera pulp nanoemulsion in the percentage of 0%, 10%, 20%, and 30% respectively. Serum levels of paraoxynase (POX) and tissue levels of malondialdehyde (MDA), nitric oxide (NO), and catalase (CAT) activity were assessed. Serum levels of nuclear factor kappa B (NF-κB), interleukin-1beta (IL-1ß), matrix metalloproteinase-9 (MMP-9), ceramide, and homocysteine (Hcy) were evaluated. Results indicated that the Aloe vera pulp nanoemulsion was appeared in spherical nano form with droplets diameter around 330 nm. Ethanol induces GU to cause a significant increase in the levels of MDA, NO, NF-κB, IL-1ß, MMP-9, Hcy, and ceramide along with a significant decrease in POX and CAT activities compared to the control group (p < 0.05). Pretreatment with different concentrations of probiotics fortified with Aloe vera pulp nanoemulsion with, especially the 30% concentration, significantly reduce the oxidative stress and ameliorate the release of different inflammatory mediators suggesting it as a promising approach in the protection against GU via scavenging superoxide radicals and inhibiting the activation of the inflammatory signaling cascades.


Asunto(s)
Aloe , Probióticos , Úlcera Gástrica , Animales , Etanol/toxicidad , Malondialdehído , Extractos Vegetales/uso terapéutico , Ratas , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/prevención & control
7.
Food Chem ; 365: 130513, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34247045

RESUMEN

This research aimed to biosynthesizing zinc oxide nanoparticles (ZnO-NPs) using lactobacilli strains. All tested lactobacilli able to biosynthesis ZnO-NPs indicated by white precipitates. The characteristics of the biosynthesis ZnO-NPs from Lactobacillus gasseri were studied using UV-visible spectroscopy, TEM, SEM, DLS, FT-IR, XRD, and antimicrobial activity. The characteristic examination depicted cubic structures, pure and spherical ZnO-NPs with a diameter size of 22 nm. Antimicrobial study of ZnO-NPs displayed better higher antimicrobial activity on food pathogens in a dose-dependent manner. Moreover, integrated biosynthesis ZnO-NPs in yogurt positively affected the shelf life of yogurt during storage for four weeks without changes in the sensory evaluation. The microbiological population of fortified yogurt significantly reduced during storage than control. But chemically evaluation of fortified yogurt indicated an increase in dry matter, protein, and ash content than control. The achieved results suggested that the low amount of biosynthesized ZnO-NPs lead to the development of properties of integrated yogurt. Furthermore, the biosynthesized ZnO-NPs additive to yogurt could be a good food source for groups suffering from zinc deficiency such as the elderly groups or vegetarians who do not eat meat and at risk of zinc inadequacy.


Asunto(s)
Lactobacillus gasseri , Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Anciano , Antibacterianos/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Espectroscopía Infrarroja por Transformada de Fourier , Yogur
8.
RSC Adv ; 11(37): 22571-22584, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-35480459

RESUMEN

In this paper we describe the preparation of a new bionanocomposite based on carboxymethyl cellulose (CMC), Arabic gum (AG) and gelatin (GL), incorporating garlic extract (GE) and TiO2 nanoparticles (TiO2-NPs). The prepared bionanocomposites were evaluated using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Energy Dispersive X-ray Analysis (EDX), and scanning electron microscopy (SEM), and were evaluated for their antimicrobial effect. The permeability and thermal and mechanical properties of the films were assessed. The water vapor transmission rate (WVTR), oxygen transmission rate (OTR), and mechanical, thermal and antimicrobial properties of the prepared bionanocomposite films were enhanced by the addition of GE and TiO2-NPs. The effects of GE and TiO2-NPs in combination incorporated into a CMC/AG/GL blend as an edible coating on the quality of fresh Nile tilapia fish fillets during refrigerated storage were evaluated. The microbiological status and weight loss of fresh Nile tilapia fish fillets were periodically tested for 21 days during storage at 4 °C. The results indicated that GE combined with TiO2-NPs has a synergistic influence on the enhancement of the preservation properties of CMC/AG/GL/GE-TiO2 bionanocomposites for refrigerated tilapia fish fillets, which could control microbial growth, and decrease weight loss during the storage of tilapia fish fillets.

9.
Carbohydr Polym ; 239: 116234, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32414443

RESUMEN

Roselle calyx extract (RE) was used to prepare zinc oxide nanoparticles (ZnO-NPs) as a green technique. In the current work, chitosan/guar gum/zinc oxide bionanocomposites based on Roselle calyx extract, namely (CS/GG/RE-ZnO) bionanocomposite were prepared. The synthetic ZnO-NPs and the prepared bionanocomposites were characterized by Fourier transforms infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Moreover, the addition of RE-ZnO nanocomposites was improved mechanical, permeability, antimicrobial and antioxidant properties of bionanocomposite films. The influence of coating Ras cheese with the fabricated CS/GG/RE-ZnO bionanocomposites on chemical, microbiological, and sensorial properties of Ras cheese was evaluated during ripening in comparing with uncoated cheese. Ras cheese coating with bionanocomposite film containing 3% RE-ZnO nanocomposites protects their surface for around three months from yeasts, molds and other bacteria growth. The prepared CS/GG/RE-ZnO bionanocomposite films can be used as a promising candidate for food packaging applications.


Asunto(s)
Queso , Quitosano/química , Materiales Biocompatibles Revestidos/síntesis química , Galactanos/química , Hibiscus/química , Mananos/química , Extractos Vegetales/química , Gomas de Plantas/química , Óxido de Zinc/química , Materiales Biocompatibles Revestidos/química , Tamaño de la Partícula , Propiedades de Superficie
10.
Heliyon ; 6(1): e03278, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31993529

RESUMEN

Spinach fine powder is a good source of protein, fiber, antioxidant, and minerals, making it a suitable ingredient to be used in the formulation of foods with high nutritional or biological values. In the current study, spinach nano-powder (0.50, 1.00, 1.50, and 2%) was used in the manufacturing of ultra-filtered soft chesses (UF-soft chesses). The quality of the cheeses was assessed by measuring their chemical compositions, colors, sensory, and antioxidant properties. Dynamic light scattering (DLS) showed that particles of spinach powder followed a normal distribution pattern with an average diameter of about 328 nm. By increasing the addition of spinach nano-powder with retentate its content of fiber, minerals, total phenolic content, and antioxidant activity was improved. Moreover, the total solid, protein and acidity contents increased significantly with the increased percentage of added spinach nano-powder reaching maximum values after four weeks of cold storage. Cheese containing 0.5% and 1% spinach powder demonstrated higher values for sensory parameters than other treatments. UF-cheese prepared in this work represents a novel functional dairy product that can potentially provide the human body with better nutrients.

11.
RSC Adv ; 10(62): 37857-37870, 2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-35515154

RESUMEN

In the present study, we formulated and characterized CMC/PVA/CuO bionanocomposites to evaluate their use in coating processed cheese. Copper oxide nanoparticles (CuO-NPs) were prepared and added to a mixed solution of carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA) using compositions of 0.3, 0.6 and 0.9% (w/v). The CMC/PVA/CuO bionanocomposites were prepared by a solution casting method and used for coating processed cheese. The fabricated bionanocomposite films and CuO-NPs were characterized by TEM, SEM, EDEX, XRD, DLS, and FT-IR analysis. Inclusion of CuO-NPs decreased the gas transmission rate (GTR) and water vapor transmission rate (WVTR) of the prepared film. Also, the bionanocomposite suspensions exhibited high but variable inhibitory effects against several pathogenic bacteria and fungi. The impact of coating of processed cheese surfaces with the prepared bionanocomposite films on microbiological, physicochemical, textural and sensory properties of the processed cheese were assessed during 6 months of cold storage. Coating cheese with film containing CuO-NPs eliminated mould growth on the cheese surface and decreased significantly (P < 0.05) the total bacterial count of the cheese. Furthermore, coating of cheese decreased the moisture losses and retarded the increase in the cheese hardness during storage. The highest acceptability at the end of the storage period was given for processed cheese coated with the bionanocomposite containing 0.9% CuO-NPs. Thus, the obtained CMC/PVA/CuO bionanocomposite films could be a promising candidate for cheese packaging applications.

12.
Colloids Surf B Biointerfaces ; 184: 110465, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31546222

RESUMEN

BACKGROUND: Cisplatin (CisPt) is one of the most widely used and highly effective drugs for the treatment of various solid tumors, unfortunately acute kidney injury (AKI) is considered one of its side effects through several mechanisms including production of reactive oxygen species (ROS), pro-inflammatory and pro-fibrotic cytokines. Due to the poor effect of AKI therapy, the use of nanoparticles loaded with natural extracts for delivering to the kidney molecules are desirable. AIM: This study aims to investigate the effectiveness of different concentrations of gold nanoparticles (Au-NPs) as a carrier for Ficus carica L. (Fig) leaves extract against CisPt induced AKI. METHODS: Seventy male albino rats were used and divided into seven groups. After the experimental period, blood was withdrawn, serum was separated for determination of urea, creatinine, homocystein (Hcy) and folic acid while reduced glutathione (GSH), nitric oxide (NO), malondialdehyde (MDA), total antioxidant capacity (TAC) and hydroxyproline content (Hyp) were evaluated in kidney tissue homogenate. RESULTS: CisPt induced AKI in rats and results in a significant increase in the levels of serum urea, creatinine, Hcy and kidney Hyp, lipid peroxidation along with a significant reduction of kidney GSH, NO and TAC compared to the control rats. Treatment with Au-NPs and Fig extract particularly in a ratio of (3:2) respectively was shown to improve renal functions with efficient capacity in scavenging ROS and reduced AKI severity. CONCLUSION: Au-NPs enhanced the anti-oxidative properties of the Fig extract in targeting kidney damaged tissue and reduced oxidative toxicity induced by CisPt.


Asunto(s)
Lesión Renal Aguda/prevención & control , Ficus/química , Oro/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Hojas de la Planta/química , Lesión Renal Aguda/sangre , Lesión Renal Aguda/inducido químicamente , Animales , Cisplatino , Creatinina/sangre , Glutatión/metabolismo , Homocisteína/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Malondialdehído/metabolismo , Nanopartículas del Metal/administración & dosificación , Fitoterapia/métodos , Extractos Vegetales/administración & dosificación , Ratas
13.
Heliyon ; 5(6): e01989, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31338458

RESUMEN

Herbs and spices come from different parts of the plant are used to impart an aroma and taste to food. Several herbs have therapeutic properties such as antioxidative, anti-inflammatory, antidiabetic, antihypertensive and antimicrobial activities. Therefore, fortification of dairy foods with herbs and spices could help to provide functional dairy products with nutritional and medicinal values. Also, herbs and spices are used to improve the appearance and attractiveness of fortified foods for consumers and to increase the sale of those herbs. Therefore, only the highest quality herbs or spices can be added to dairy products to combat contaminating microorganisms. In this review the latest progresses in the dairy sector concerning the addition of numerous herbs and spices in different forms (i.e. powder, fresh, extract, essential oils) to dairy food has been conversed. Also, the effects of those herbs and spices on the quality of dairy products such as yoghurts, cheeses, butter, gee and ice creams have been presented.

14.
Carbohydr Polym ; 193: 19-27, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29773372

RESUMEN

Bionanocomposites materials open a chance for the usage of novel, high performance, lightweight, and ecofriendly composite materials making them take place the traditional non-biodegradable plastic packaging materials. Biopolymers like polysaccharides such as chitosan (CS), carboxymethyl cellulose (CMC), starch and cellophane could be used to resolve environmental hazards owing to their biodegradability and non-toxicity. In addition these advantages, polysaccharides have some disadvantages for example poor mechanical properties and low resistance to water. Therefore, nanomaterials are used to improve the thermal, mechanical and gas barrier properties without hindering their biodegradable and non-toxic characters. Furthermore, the most favorable nanomaterials are layered silicate nanoclays for example montmorillonite (MMT) and kaolinite, zinc oxide (ZnO-NPs), titanium dioxide (TiO2-NPs), and silver nanoparticles (Ag-NPs). In packaging application, the improvement of barrier properties of prepared films against oxygen, carbon dioxide, flavor compounds diffusion through the packaging films. Wide varieties of nanomaterials are suitable to offer smart and/or intelligent properties for food packaging materials, as demonstrated by oxygen scavenging capability, antimicrobial activity, and sign of the level of exposure to various harmful features for instance oxygen levels or insufficient temperatures. The compatibility between nanomaterials and polymers matrix consider the most challenge for the preparation of bionanocomposites as well as getting whole distribution of nanoparticles into the polymer matrix. We keen in this review the development of packaging materials performance and their mechanical, degradability and thermal stability as well as antibacterial activity for utilization of bionanocomposites in different packaging application is considered.

15.
Int J Biol Macromol ; 115: 1002-1011, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29723621

RESUMEN

Bionanocomposites have attracted a tremendous level of consideration as alternatives for a broad group of commercial materials based on petroleum-derived compounds and used for coating cheese. Sustainable, economical and environmentally compatible materials based on chitosan (CS), poly vinyl alcohol (PVA), glycerol (Gy) and titanium dioxide nanoparticles (TiO2-NPs) were prepared. Moreover, the prepared bionanocomposites (CS/PVA/Gy/TiO2-NPs) were characterized using XRD, SEM, TEM, WVTR and mechanical strength. The developed CS/PVA/Gy/TiO2-NPs bionanocomposites exhibited homogeneous, compact morphological features and enhanced mechanical and barrier properties. Also, the prepared bionanocomposite exhibited variable inhibitory effects against several pathogenic bacteria and fungi. Karish was made and coated with the prepared bionanocomposite containing 1, 2 and 3% TiO2-NPs, and cold stored. Changes in the weight losses, cheese composition, microbiological quality, textural parameters, and sensory properties were followed during storage for 25 days. Coated Karish cheese retained acceptable quality until the end of the storage period, while uncoated developed surface fungi growth and deteriorated quality after 15 days. Karish cheese coated with the bionanocomposite containing 3% TiO2-NPs ranked the highest acceptability at the end of storage period.


Asunto(s)
Antiinfecciosos/química , Queso , Embalaje de Alimentos , Leche/química , Nanocompuestos/química , Animales , Antiinfecciosos/farmacología , Aspergillus flavus/efectos de los fármacos , Quitosano/química , Almacenamiento de Alimentos , Glicerol/química , Fenómenos Mecánicos , Nanopartículas/química , Alcohol Polivinílico/química , Staphylococcus aureus/efectos de los fármacos , Gusto , Titanio/química , Yersinia enterocolitica/efectos de los fármacos
16.
Carbohydr Polym ; 151: 9-19, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27474538

RESUMEN

A novel bionanocomposites packaging material prepared using chitosan (CH), carboxymethyl cellulose (CMC), and zinc oxide nanoparticles (ZnO-NPs), namely CH/CMC/ZnO bionanocomposites, was prepared by casting method. The CH/CMC/ZnO bionanocomposites were investigated using FT-IR, TEM, SEM, XRD, and TGA. The acquired bionanocomposites exhibited improved mechanical and thermal properties compare with the biocomposites (CH/CMC) blend. The soft white cheese were manufactured, packaged within the prepared bionanocomposites films and stored at 7°C for 30days. The influence of packaging material on packaged cheese (rheological properties, colour measurements, moisture, pH and titratable acidity) were assessed. Furthermore, the effect of packaging material on the total bacterial counts, mold & yeast and coliform in cheese was evaluated. The prepared bionanocomposites displayed good antibacterial activity against gram positive (Staphylococcus aureus), gram negative (Pseudomonas aeruginosa, Escherichia coli) bacteria and fungi (Candidia albicans). Moreover, the packaging films assisted in increasing the shelf life of white soft cheese. Therefore, it can be used in food packaging applications.


Asunto(s)
Antiinfecciosos , Carboximetilcelulosa de Sodio , Quitosano , Embalaje de Alimentos , Nanocompuestos , Óxido de Zinc , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Carboximetilcelulosa de Sodio/administración & dosificación , Carboximetilcelulosa de Sodio/química , Queso/microbiología , Quitosano/administración & dosificación , Quitosano/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Almacenamiento de Alimentos , Nanocompuestos/administración & dosificación , Nanocompuestos/química , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Óxido de Zinc/administración & dosificación , Óxido de Zinc/química
17.
Carbohydr Polym ; 132: 274-85, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26256350

RESUMEN

Novel bionanocomposites based on chitosan/poly(vinyl alcohol)/titanium nanoparticles (CS/PVA/TiO2 nanocomposite) were prepared and used as packaging materials for soft white cheese. The prepared bionanocomposites were characterized using XRD, SEM, TEM and FT-IR. The CS/PVA/TiO2 bionanocomposites exhibited good mechanical properties. Furthermore, the obtained bionanocomposites exhibited superior antibacterial activity against gram positive (Staphylococcus aureus), gram negative (Pseudomonas aeruginosa, Escherichia coli) bacteria and fungi (Candidia albicans). The soft white cheese was manufactured and packaged within the CS/PVA/TiO2 nanocomposite films and stored at 7 °C for 30 days. The color, rheological and chemical properties of cheese were evaluated, also the influence of CS/PVA/TiO2 bionanocomposites on microbiological analysis of soft white cheese was assessed, the results indicated that the total bacterial counts, mold & yeast and coliform decreased with the increasing storage period and disappeared at the end of storage period compared with control. Consequently, CS/PVA/TiO2 bionanocomposite can be used in food packaging applications.


Asunto(s)
Antiinfecciosos/química , Queso/microbiología , Quitosano/química , Embalaje de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Nanocompuestos/química , Titanio/química , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Candida/efectos de los fármacos , Candidiasis/prevención & control , Queso/análisis , Quitosano/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/prevención & control , Bacterias Grampositivas/efectos de los fármacos , Infecciones por Bacterias Grampositivas/prevención & control , Humanos , Nanopartículas del Metal/química , Alcohol Polivinílico/química , Alcohol Polivinílico/farmacología , Titanio/farmacología
18.
Int J Biol Macromol ; 76: 25-32, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25709016

RESUMEN

Zinc oxide (ZnO) nanoparticle was successfully synthesized using hydrothermal method as well as, silver (Ag) nanoparticle was direct prepared during chitosan nanocomposites preparation. Chitosan films were investigated by recognized the effect of kinds of acids (formic or acetic acid). Correspondingly, using of concentrated NaOH was checking for facilitating de-casting of the films. Utilization of formic acid arisen higher quality films than those films produced using acetic acid as solvent. Optimization was based on the mechanical properties for both types of acids solvent. Furthermore, the elasticity of the prepared films was enhanced by blending hydroxyl ethylcellulose (HEC) with chitosan. Loading the films by silver and zinc oxide nanoparticles (Ag-NPs and ZnO) was achieved during the preparation of films under the optimum conditions. Characterizations of the prepared ZnO nanoparticles and the prepared nanocomposites films were investigated by FT-IR, XRD, SEM, TEM and EDAX. Chitosan nanocomposite films displayed good Antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella typhamrium, Bacillus cereus, and Listeria monocyte. Therefore, these films can be used for packaging applications.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Quitosano/química , Quitosano/farmacología , Fenómenos Mecánicos , Nanocompuestos/química , Bacterias/efectos de los fármacos , Ensayo de Materiales , Estructura Molecular , Nanocompuestos/ultraestructura , Nanopartículas/química , Nanopartículas/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Difracción de Rayos X , Óxido de Zinc/química
19.
Int J Biol Macromol ; 69: 185-91, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24875320

RESUMEN

Chitosan-silver (CS-Ag) and Chitosan-gold (CS-Au) nanocomposites films were synthesized by a simple chemical method. A local bacterial isolate identified as Bacillus subtilis ss subtilis was found to be capable to synthesize both silver nanoparticles (Ag-NP) and gold nanoparticles (Au-NP) from silver nitrate (AgNO3) and chloroauric acid (AuCl(4-)) solutions, respectively. The biosynthesis of both Ag-NP and Au-NP characterize using UV/vis spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD), and then added to chitosan by different ratios (0.5, 1 and 2%). The prepared chitosan nanocomposites films were characterize using UV, XRD, SEM and TEM. Moreover, the antibacterial activity of the prepared films was evaluated against gram positive (Staphylococcus aureus) and gram negative bacteria (Pseudomonas aerugenosa), fungi (Aspergillus niger) and yeast (Candida albicans). Therefore, these materials can be potential used as antimicrobial agents in packaging applications.


Asunto(s)
Bacillus subtilis/metabolismo , Quitosano/química , Oro/química , Nanopartículas del Metal/química , Nanocompuestos/química , Embalaje de Productos , Plata/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Aspergillus niger/efectos de los fármacos , Bacillus subtilis/efectos de los fármacos , Oro/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Plata/metabolismo , Propiedades de Superficie
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