Methods for nanoemulsion and nanoencapsulation of food bioactives

Environmental Chemistry Letters - Nanoencapsulation is a promising technology allowing miniaturized dosage and administration of valuable volatiles, degradable bioactives and biologicals. The...     

Food-grade nanoencapsulation of vitamins

Environmental Chemistry Letters - Vitamin deficiency arises when the dietary intake of essential vitamins is too low. Insufficient levels of vitamin weaken the body and induce diseases. Although...     

Titanium dioxide nanoparticles induce bacterial membrane rupture by reactive oxygen species generation

Nano-titania is widely used in the food industry due to its efficient antimicrobial activity. However, the mechanism of microbial toxicity of nano-titania is poorly known. Here, nano-TiO₂ has been fabricated by microwave-irradiation chemistry, a new method, and then tested for antimicrobial activity. Mutagenicity of nano-TiO₂ was evaluated using Salmonella typhimurium histidine-auxotrophic strains. The reactive oxygen generation test was performed using 2,7-dichlorofluorescein diacetate dye. To test membrane permeabilization, E. coli cultures were grown in nutrient broth at an optical density of 0.3–0.5 at 610 nm, harvested by centrifugation at 11,000g for 10 min, washed and resuspended in 0.5 % NaCl solution. We also analyzed superoxide formation and membrane integrity, and we used scanning electron microscopy. Results show that nano-TiO₂ has a minimum inhibitory concentration of 15 µg/mL, and a minimum bactericidal concentration of 20 µg/mL for E. coli. The bacterial inner wall was ruptured, and cytoplasmic content was released after 5 min of treatment in a dose-dependent manner. Notably, superoxide formation was not observed, which establishes the fact that reactive oxygen generation and alteration of membrane integrity, as well as permeability, is the major mechanism of antimicrobial activity of nano-TiO₂.     

Applications of nanotechnology in agriculture and water quality management

Due to their small size and unique physico-chemical characteristics, nanomaterials have gained importance in the agri-food sector, notably in preservation and packaging. Future applications will focus on shelf life, food quality, safety, fortification and biosensors for contaminated or spoiled food, irrigating water and drinking water. Different types and shapes of nanomaterials are being used depending upon the needs and nature of the work in agriculture and water quality management. Here we review the application of nanotechnology in agriculture. The major points discussed are: (1) Nanomaterials for agriculture and water quality management. (2) Research interests such as nanoscale carriers, fabricated xylem vessels, nanolignocellulosic materials, clay nanotubes, photocatalysis, bioremediation of resistant pesticides, disinfectants, agricultural wastewater treatment, nanobarcode technology, quantum dots for staining bacteria and nanobiosensors. (3) Nanotechnological applications for agriculture, which includes nanolignodynamic metallic particles, photocatalysis, desalination, removal of heavy metals and wireless nanosensors.     

Electrospun nanofibers of polyvinylidene fluoride incorporated with titanium nanotubes for purifying air with bacterial contamination

Environmental Science and Pollution Research - Polyvinylidene fluoride (PVDF) blended with varying concentrations of titanium nanotubes (TNT) was electrospun to result in a nanocomposite filter...     

Toxicity and regulations of food nanomaterials

Environmental Chemistry Letters - Food nanotechnology has been rapidly growing in last decade due to the unique properties of nanomaterials. Nonetheless, the presence of nanomaterials in food...     

Development of food-grade antimicrobials of fenugreek oil nanoemulsion—bioactivity and toxicity analysis

Environmental Science and Pollution Research - Antimicrobials of natural origin are proving to be an effective solution to emerging antimicrobial resistance and its physiological side effects....     

Nanoemulsions in food: market demand

Environmental Chemistry Letters - Food nanotechnology involves the study of interactions between oil, water, surfactants and various ingredients such as active compounds, gelling agents,...     

Thermal co-reduction approach to vary size of silver nanoparticle: its microbial and cellular toxicology

In recent years, silver nanoparticles (AgNPs) have attracted considerable interest in the field of food, agriculture and pharmaceuticals mainly due to its antibacterial activity. AgNPs have also been reported to possess toxic behavior. The toxicological behavior of nanomaterials largely depends on its size and shape which ultimately depend on synthetic protocol. A systematic and detailed analysis for size variation of AgNP by thermal co-reduction approach and its efficacy toward microbial and cellular toxicological behavior is presented here. With the focus to explore the size-dependent toxicological variation, two different-sized NPs have been synthesized, i.e., 60 nm (Ag60) and 85 nm (Ag85). A detailed microbial toxicological evaluation has been performed by analyzing minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), diameter of inhibition zone (DIZ), growth kinetics (GrK), and death kinetics (DeK). Comparative cytotoxicological behavior was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. It has been concluded by this study that the size of AgNPs can be varied, by varying the concentration of reactants and temperature called as “thermal co-reduction” approach, which is one of the suitable approaches to meet the same. Also, the smaller AgNP has shown more microbial and cellular toxicity.