Biopolymer Composite Materials with Antimicrobial Effects Applied to the Food Industry

Given the increasing number of antibiotic-resistant bacteria and the need to synthesize new antimicrobials, silver has attracted interest in the scientific community because of its recognized antimicrobial activity. This study aimed to evaluate the antimicrobial effects of silver nanoparticles (NP) obtained by a new method and tested at concentrations of 6 μg/ml and 60 μg/ml against the species Staphylococcus aureus, Listeria innocua, Salmonella Choleraesuis, Pseudomonas aeruginosa, Escherichia coli, and Bacillus cereus. The ability of these nanoparticles to remove or kill vegetative cells adhered to stainless steel surfaces was also evaluated. We observed that the NP obtained with the new method, concentrated silver nanoparticles (CNP), and silver nanoparticles with added sodium chloride (NPNaCl) had high antimicrobial activities (P < 0.05). We also verified that the most effective condition for the removal of P. aeruginosa cells on stainless steel coupons (10 by 10 mm) was immersion of the surfaces in CNP. The CNP treatment produced a 5-log reduction of the microbial population after 30 to 60 min of immersion. The CNP treatment also performed better than water and sodium carbonate, a compound commonly applied in clean-in-place procedures in the food industry, in removing adherent B. cereus cells from stainless steel cylinders. Therefore, these results suggest that NP synthesized by a new procedure may be used as antimicrobials in the food industry, for example, for the sanitization of utensils that come into contact with foods.

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Destruction of Listeria monocytogenes Biofilms on Stainless Steel Using Monolaurin and Heat1

Journal of Food Protection ◽

10.4315/0362-028x-58.3.251 ◽

1995 ◽

Vol 58 (3) ◽

pp. 251-255 ◽

Cited By ~ 25

Author(s):

DEOG-HWAN OH ◽

DOUGLAS L. MARSHALL

Keyword(s):

Stainless Steel ◽

Listeria Monocytogenes ◽

Food Industry ◽

Adherent Cells ◽

Planktonic Cells ◽

Antimicrobial Effects ◽

Biofilm Removal ◽

Nutrient Environment ◽

Physical Treatments

Individual and combined antimicrobial effects of monolaurin and heat on planktonic, 1-day adherent, or 7-day adherent cells of Listeria monocytogenes were determined to evaluate biofilm removal from stainless steel. Planktonic cells were more sensitive to heat and monolaurin than were cells attached to stainless steel. Young (1-day) biofilm cells were more sensitive to each treatment than were old (7-day) biofilm cells. Adherent cells were destroyed by 50 μg/ml monolaurin combined with heating at 65°C for 5 min. Cells in a rich nutrient environment were more resistant to treatment than were cells in a depleted nutrient environment. Results demonstrate the usefulness of combining chemical and physical treatments to control L. monocytogenes biofilm problems in the food industry.

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Anacardium Plants: Chemical,Nutritional Composition and Biotechnological Applications

Biomolecules ◽

10.3390/biom9090465 ◽

2019 ◽

Vol 9 (9) ◽

pp. 465 ◽

Cited By ~ 5

Author(s):

Salehi ◽

Gültekin-Özgüven ◽

Kırkın ◽

Özçelik ◽

Morais-Braga ◽

...

Keyword(s):

Secondary Metabolites ◽

Food Industry ◽

Nutritional Composition ◽

Anacardium Occidentale ◽

Biotechnological Applications ◽

Tropical Regions ◽

Antimicrobial Effects ◽

Interesting Approach ◽

Food Applications ◽

Cashew Tree

Anacardium plants are native to the American tropical regions, and Anacardium occidentale L. (cashew tree) is the most recognized species of the genus. These species contain rich secondary metabolites in their leaf and shoot powder, fruits and other parts that have shown diverse applications. This review describes the habitat and cultivation of Anacardium species, phytochemical and nutritional composition, and their industrial food applications. Besides, we also discuss the secondary metabolites present in Anacardium plants which display great antioxidant and antimicrobial effects. These make the use of Anacardium species in the food industry an interesting approach to the development of green foods.

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Chitosan-Based Composite Materials for Prospective Hemostatic Applications

Marine Drugs ◽

10.3390/md16080273 ◽

2018 ◽

Vol 16 (8) ◽

pp. 273 ◽

Cited By ~ 49

Author(s):

Zhang Hu ◽

Dong-Ying Zhang ◽

Si-Tong Lu ◽

Pu-Wang Li ◽

Si-Dong Li

Keyword(s):

Composite Materials ◽

Research And Development ◽

Chemical Industry ◽

Food Industry ◽

Future Perspectives ◽

Multiple Forms

Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.

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Comparative Microstructures of Ion Milled and Electrochemically Thinned Composite Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052742 ◽

1974 ◽

Vol 32 ◽

pp. 546-547

Author(s):

R.R. Russell

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Composite Materials ◽

Great Difficulty ◽

Ion Milling ◽

Transmission Electron ◽

Ion Damage ◽

Intermetallic Composite

Transmission electron microscopy of metallic/intermetallic composite materials is most challenging since the microscopist typically has great difficulty preparing specimens with uniform electron thin areas in adjacent phases. The application of ion milling for thinning foils from such materials has been quite effective. Although composite specimens prepared by ion milling have yielded much microstructural information, this technique has some inherent drawbacks such as the possible generation of ion damage near sample surfaces.

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Transmission electron microscopy of composite materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107125 ◽

1988 ◽

Vol 46 ◽

pp. 1012-1015

Author(s):

K.P.D. Lagerlof

Keyword(s):

Composite Materials ◽

Physical Properties ◽

Structural Defects ◽

Structural Composites ◽

Multiphase Materials ◽

Structural Reinforcement ◽

Transmission Electron ◽

Reinforced Fiber ◽

Particulate Reinforced Composites ◽

Definition Of

Although most materials contain more than one phase, and thus are multiphase materials, the definition of composite materials is commonly used to describe those materials containing more than one phase deliberately added to obtain certain desired physical properties. Composite materials are often classified according to their application, i.e. structural composites and electronic composites, but may also be classified according to the type of compounds making up the composite, i.e. metal/ceramic, ceramic/ceramie and metal/semiconductor composites. For structural composites it is also common to refer to the type of structural reinforcement; whisker-reinforced, fiber-reinforced, or particulate reinforced composites [1-4].For all types of composite materials, it is of fundamental importance to understand the relationship between the microstructure and the observed physical properties, and it is therefore vital to properly characterize the microstructure. The interfaces separating the different phases comprising the composite are of particular interest to understand. In structural composites the interface is often the weakest part, where fracture will nucleate, and in electronic composites structural defects at or near the interface will affect the critical electronic properties.

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Where’s the fat? Freeze-fracture analysis of ingredient interactions in food systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146084 ◽

1993 ◽

Vol 51 ◽

pp. 48-49

Author(s):

Jean Fincher

Keyword(s):

Lipid Droplets ◽

Food Systems ◽

Food Industry ◽

Freeze Fracture ◽

Food Science ◽

Complex Interactions ◽

Fat Reduction ◽

Important Trend ◽

Conventional Foods ◽

Whipped Cream

An important trend in the food industry today is reduction in the amount of fat in manufactured foods. Often fat reduction is accomplished by replacing part of the natural fat with carbohydrates which serve to bind water and increase viscosity. It is in understanding the roles of these two major components of food, fats and carbohydrates, that freeze-fracture is so important. It is well known that conventional fixation procedures are inadequate for many food products, in particular, foods with carbohydrates as a predominant structural feature. For some food science applications the advantages of freeze-fracture preparation procedures include not only the avoidance of chemical fixatives, but also the opportunity to control the temperature of the sample just prior to rapid freezing.In conventional foods freeze-fracture has been used most successfully in analysis of milk and milk products. Milk gels depend on interactions between lipid droplets and proteins. Whipped emulsions, either whipped cream or ice cream, involve complex interactions between lipid, protein, air cell surfaces, and added emulsifiers.

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