Raksha Pandit

Antimicrobial peptides as natural bio-preservative to enhance the shelf-life of food

Antimicrobial peptides (AMPs) are diverse group of natural proteins present in animals, plants, insects and bacteria. These peptides are responsible for defense of host from pathogenic organisms. Chemical, enzymatic and recombinant techniques are used for the synthesis of antimicrobial peptides. These peptides have been found to be an alternative to the chemical preservatives. Currently, nisin is the only antimicrobial peptide, which is widely utilized in the preservation of food. Antimicrobial peptides can be used alone or in combination with other antimicrobial, essential oils and polymeric nanoparticles to enhance the shelf-life of food. This review presents an overview on different types of antimicrobial peptides, purification techniques, mode of action and application in food preservation.

Curcumin nanoparticles: physico-chemical fabrication and its in vitro efficacy against human pathogens

Curcumin is one of the polyphenols, which has been known for its medicinal use since long time. Curcumin shows poor solubility and low absorption, and therefore, its use as nanoparticles is beneficial due to their greater solubility and absorption. The main aim of the present study was the formation of curcumin nanoparticles (Nano curcu), evaluation of their antibacterial activity against human pathogenic bacteria and formulation of Nano curcu-based cream. We synthesized Nano curcu by sonication method. The synthesis of Nano curcu was assessed for their solubility in water and by UV–visible spectrophotometry. Further, the nanoparticles were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, nanoparticle tracking and analysis, and zeta potential analysis. In vitro antibacterial activity of Nano curcu was evaluated against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The cream containing Nano curcu was found to be effective against human bacterial pathogens and hence can be used for treatment of bacterial diseases.

Biosynthesis of zinc oxide nanoparticles by petals extract of Rosa indica L., its formulation as nail paint and evaluation of antifungal activity against fungi causing onychomycosis

Aim: The authors report the biological synthesis of zinc oxide nanoparticles (ZnO-NPs) from the petals extract of Rosa indica L. (rose). Its efficacy was evaluated against two dermatophytes: namely: Trichophyton mentagrophytes and Microsporum canis which cause onychomycosis. The activity of antibiotics against the tested dermatophytes was enhanced, when evaluated in combination with ZnO-NPs. Methods and results: The synthesised ZnO-NPs were preliminary detected by using ultraviolet UV visible spectroscopy, which showed specific absorbance. The ZnO-NPs were further characterised by nanoparticle tracking analysis (NTA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction and Zetasizer. Moreover, nanoparticles containing nail paint (nanopaint) was formulated and its antifungal activity was also assessed against T. mentagrophytes and M. canis. ZnO-NPs and formulated nanopaint containing ZnO-NPs, both showed significant antifungal activity. The maximum activity was noted against M. canis and lesser against T. mentagrophytes. Minimum inhibitory concentration of ZnO-NPs was also determined against the dermatophytes causing onychomycosis infection. Conclusion: ZnO-NPs can be utilised as a potential antifungal agent for the treatment of onychomycosis after more experimental trials.

Potential applications of curcumin and curcumin nanoparticles: from traditional therapeutics to modern nanomedicine

Abstract Curcumin (diferuloylmethane) is one of the potent, nontoxic, and major bioactive components present in turmeric. The major drawbacks of curcumin are low absorption and poor bioavailability. The present review highlights on the methods for the fabrication of curcumin nanoparticles and their applications in treatment of cancer and wound infections. Curcumin nanoparticles possess remarkable antibacterial, antiviral, and antiprotozoan activity. Hence, curcumin nanoparticle-loaded nano-gel, microemulsion, and nano-cream can be used for drug delivery.

Association of Silver Nanoparticles and Curcumin Solid Dispersion: Antimicrobial and Antioxidant Properties

The last century, more precisely after 1945, was marked by major advances in the treatment of infectious diseases which promoted a decrease in mortality and morbidity. Despite these advances, currently the development of antimicrobial resistance has been growing drastically and therefore there is a pressing need to search for new compounds. Silver nanoparticles (AgNps) have been demonstrating good antimicrobial activity against different bacteria, viruses, and fungi. Curcumin (CUR) extracted from rhizomes of Curcuma longa has a variety of applications including antiinflammatory, antioxidant, and antibacterial agent. The association between silver nanoparticles and curcumin in a formulation can be a good alternative to control infectious diseases due the antimicrobial properties of both compounds. The objective of this work was to develop a formulation composed of a thermoresponsive gel—with antimicrobial and antioxidant properties due to the association of AgNps with PVP and PVA polymers. After AgNp synthesis, these were incorporated together with the previously prepared CUR/P407 (1:2) solid dispersion (SD) into a polymer dispersion of 20% P407 (thermosensitive gel). Our results showed that the association between the AgNps with CUR SD demonstrated good antioxidant activity as compared to the standard compound. Measures of MIC showed more efficacy against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) than for Gram-positive bacteria (Staphylococcus aureus). This association enhances antimicrobial activity against E. coli and P aeruginosa and added antioxidant value in formulations.

Broadening the spectrum of small-molecule antibacterials by metallic nanoparticles to overcome microbial resistance

Now-a-days development of microbial resistancce have become one of the most important global public health concerns. It is estimated that about 2 million people are infected in USA with multidrug resistant bacteria and out of these, about 23,000 die per year. In Europe, the number of deaths associated with infection caused by MDR bacteria is about 25,000 per year, However, the situation in Asia and other devloping countries is more critical. Considering the increasing rate of antibiotic resistance in various pathogens, it is estimated that MDR organisms can kill about 10 million people every year by 2050. The use of antibiotics in excessive and irresponsible manner is the main reason towards its ineffectiveness. However, in this context, promising application of nanotechnology in our everyday life has generated a new avenue for the development of potent antimicrobial materials and compounds (nanoantimicrobials) capable of dealing with microbial resistance. The devlopement and safe incorporation of nanoantimicrobials will bring a new revolution in health sector. In this review, we have critically focused on current worldwide situation of antibiotic resistance. In addition, the role of various nanomaterials in the management of microbial resistance and the possible mechanisms for antibacterial action of nanoparticles alone and nanoparticle-antibiotics conjuagte are also discussed.

Bioenergy and Biofuels: Nanotechnological Solutions for Sustainable Production

Rather than using fossil fuels, the world is focusing on finding or developing alternative modes of energy production. This is due to the fact that fossil fuels are exhausting and the emission products of these fuels have been causing several damages to the environment. In this context, nanotechnology can play an important role for sustainable bioenergy and biofuel production. Different nanomaterials, such as metal nanoparticles, nanofiber, nanotubes, nanosheets, and others, have been reported to have a number of direct or indirect applications (as nanocatalyst) in the production of biofuels such as bioethanol and biodiesel. Actually, these biofuels are eco-friendly and renewable energy resources and hence have been receiving attention as an alternative energy source. Also, nanotechnology offers interesting approaches such as the use of magnetic nanoparticles. These particles can be used as carrier to immobilize enzymes that can be applied in bioethanol or biodiesel production. Moreover, magnetic nanoparticles can also be used for biogas production due to strong paramagnetic property and high coercivity during the process of methanogenesis. In this chapter, after introducing a global view about bioenergy and biofuel, different and interesting approaches regarding the application and solutions that nanotechnology can offer to bioenergy and biofuel production will be discussed followed by a section about safety issue concerning this technology.

Platinum in Biomedical Applications

For a long time, platinum (Pt) is used in medicine because of its outstanding properties such as biocompatibility, electrical conductivity, radiopacity, and durability. Despite the high cost of the noble metal, its unique properties were exploited in a large number of medical devices. These include stents, catheters, pacemakers, defibrillators, cochlear implants, and many others. Pt compounds play an important role in cancer therapy. In the age of nanotechnology, the horizon of the potential applications of Pt was substantially expanded. Nanostructured Pt-based materials were proposed for producing electrodes with advanced characteristics embedded in implantable electronic devices and sensors for detection of biologically important molecules. Pt nanoparticles (PtNPs) are perspective for the treatment of the diseases related to oxidative stress. It is expected that nanoparticle formulations will reduce adverse effects of Pt-based anticancer drugs. In this chapter, we review the traditional and new fields of Pt application in medicine. Special attention is paid to the questions of in vivo biocompatibility and corrosion behavior of Pt implants. In conclusion, we summarize the benefits of Pt usage for future medicine and diagnostics and indicate the problems to be solved to give the green light for the Pt-based new products to get entry in medical market.

Metal Nanoparticles in Management of Diseases of the Central Nervous System

Abstract Central nervous system (CNS) or neurological disorders are very serious problems and major health concerns all over the world. Various treatment strategies have been investigated but the label of low therapeutic success is always associated with them. The main reason behind the low success rate is active drug molecules that are unable to reach their target sites of action inside the body. In addition, various CNS barriers such as the blood-brain barrier, the blood-cerebrospinal fluid barrier, etc., always hinder the circulation of therapeutic drugs in the body. Therefore, considering the last decades contribution of nanotechnology in the biomedical sector, it is believed that the problem of ever-increasing neurological disorders can only be managed by nanotechnology. Nanotechnology offers many exciting and promising new means of treating neurological disease. In this chapter, we have mainly focused on various aspects related to CNS diseases involving current treatment strategies and their limitations, the necessity of nanoneuromedicines, the role of nanotechnology in the diagnosis and treatment of CNS diseases, and toxicological issues.

Copper and copper nanoparticles: role in management of insect-pests and pathogenic microbes

Abstract Crop losses mainly occur due to biotic factors, which include soil-borne phytopathogens, insect pests, parasites, and predators. The major loss of food in the food industry is due to its spoilage by various microorganisms. With advancement in nanotechnology, the use of nanoparticles in food and agriculture crop yield can be improved. In this context, copper nanoparticles (CuNPs) have attracted a great deal of attention from all over the world due to their broad-spectrum antimicrobial activity. Copper is one of the key micronutrients, which plays an important role in growth and development of plants. CuNP-based fertilizer and herbicide can be used in agriculture. The small size of CuNPs facilitates their easy absorption by the plants. CuNPs can be promisingly used in the food packaging to avoid the growth of food spoilage microorganisms. The use of CuNP-based agar packaging materials has substantial potential to increase the shelf-life of food. The present review focuses on the application of Cu and CuNPs in food and agriculture. Moreover, antimicrobial and pesticidal properties of CuNPs are also discussed.