Synthesis of curcumin-loaded chitosan phosphate nanoparticle and study of its cytotoxicity and antimicrobial activity

The Effect of Curcumin-Loaded Glucan Nanoparticles on Immune Cells: Size as a Critical Quality Attribute

Curcumin is known for its multiple health benefits, largely due to its antioxidant and anti-inflammatory properties. It has been extensively studied as a therapeutic agent, however, it does not have good clinical efficacy due to its poor water solubility and bioavailability. Despite accepting the encapsulation of this compound in polymeric particles as one of the most promising strategies to increase its therapeutic value, these nanoparticles have fallen short of expectations due to a lack of assessment of their possible adverse effects on the immune system. Therefore, in this work, we report on a new method to encapsulate curcumin into glucan nanoparticles and their effects on cells of the immune system were evaluated. Two different-sized curcumin-loaded glucan NPs (GluCur 100 and GluCur 380) were produced, each with an encapsulation efficiency close to 100%, and were characterized regarding their size distribution, surface properties, and morphology. The results revealed the greatest hemolytic effect and cytotoxicity for the smallest particles (100 nm) tested in human PBMCs and RAW 264.7 cells. Although GluCur 380 NPs showed a weaker ROS production, they were able to inhibit the production of NO by macrophages. Furthermore, we found that the coagulation time was not affected by both sized-particles as well as platelet function. Additionally, both nanoparticles induced lymphocyte proliferation and TNF-α secretion by Mo-DCs. In conclusion, this report emphasizes the importance of the immunotoxicity assessment and how this is dependent on the intrinsic properties of nanomaterials, hopefully contributing to increasing the safety of nanomedicines.

Construction of nano slow-release systems for antibacterial active substances and its applications: A comprehensive review

At present, nano-carrier materials with antibacterial activity are of great significance. Due to the widespread resistance of many pathogenic microorganisms, it has seriously threatened human health. The natural antimicrobial substances extracted from fruits and vegetables can significantly improve their stability combined with nano-carrier materials. The resistance of pathogenic microorganisms will be substantially reduced, greatly enhancing the effect of active antimicrobial substances. Nanotechnology has excellent research prospects in the food industry, antibacterial preservation, food additives, food packaging, and other fields. This paper introduces nano-carrier materials and preparation techniques for loading and encapsulating active antibacterial substances in detail by constructing a nano-release system for active antibacterial substances. The antibacterial effect can be achieved by protecting them from adverse external conditions and destroying the membrane of pathogenic microorganisms. The mechanism of the slow release of the bacteriostatic active substance is also described. The mechanism of carrier loading and release is mainly through non-covalent forces between the bacteriostatic active substance and the carrier material, such as hydrogen bonding, π-π stacking, van der Waals forces, electrostatic interactions, etc., as well as the loading and adsorption of the bacteriostatic active substance by the chemical assembly. Finally, its wide application in food and medicine is introduced. It is hoped to provide a theoretical basis and technical support for the efficient utilization and product development of bacteriostatic active substances.

Critical Review on Nutritional, Bioactive, and Medicinal Potential of Spices and Herbs and Their Application in Food Fortification and Nanotechnology

Medicinal or herbal spices are grown in tropical moist evergreen forestland, surrounding most of the tropical and subtropical regions of Eastern Himalayas in India (Sikkim, Darjeeling regions), Bhutan, Nepal, Pakistan, Iran, Afghanistan, a few Central Asian countries, Middle East, USA, Europe, South East Asia, Japan, Malaysia, and Indonesia. According to the cultivation region surrounded, economic value, and vogue, these spices can be classified into major, minor, and colored tropical spices. In total, 24 tropical spices and herbs (cardamom, black jeera, fennel, poppy, coriander, fenugreek, bay leaves, clove, chili, cassia bark, black pepper, nutmeg, black mustard, turmeric, saffron, star anise, onion, dill, asafoetida, celery, allspice, kokum, greater galangal, and sweet flag) are described in this review. These spices show many pharmacological activities like anti-inflammatory, antimicrobial, anti-diabetic, anti-obesity, cardiovascular, gastrointestinal, central nervous system, and antioxidant activities. Numerous bioactive compounds are present in these selected spices, such as 1,8-cineole, monoterpene hydrocarbons, γ-terpinene, cuminaldehyde, trans-anethole, fenchone, estragole, benzylisoquinoline alkaloids, eugenol, cinnamaldehyde, piperine, linalool, malabaricone C, safrole, myristicin, elemicin, sinigrin, curcumin, bidemethoxycurcumin, dimethoxycurcumin, crocin, picrocrocin, quercetin, quercetin 4'-O-β-glucoside, apiol, carvone, limonene, α-phellandrene, galactomannan, rosmarinic acid, limonene, capsaicinoids, eugenol, garcinol, and α-asarone. Other than that, various spices are used to synthesize different types of metal-based and polymer-based nanoparticles like zinc oxide, gold, silver, selenium, silica, and chitosan nanoparticles which provide beneficial health effects such as antioxidant, anti-carcinogenic, anti-diabetic, enzyme retardation effect, and antimicrobial activity. The nanoparticles can also be used in environmental pollution management like dye decolorization and in chemical industries to enhance the rate of reaction by the use of catalytic activity of the nanoparticles. The nutritional value, phytochemical properties, health advantages, and both traditional and modern applications of these spices, along with their functions in food fortification, have been thoroughly discussed in this review.

Graphene oxide quantum dot-chitosan nanotheranostic platform as a pH-responsive carrier for improving curcumin uptake internalization: In vitro & in silico study

We herein fabricated a cancer nanotheranostics platform based on Graphene Oxide Quantum Dot-Chitosan-polyethylene glycol nanoconjugate (GOQD-CS-PEG), which were targeted with MUC-1 aptamer towards breast and colon tumors. The interaction between aptamer and MUC-1 receptor on the desired cells was investigated utilizing molecular docking. The process of curcumin release was investigated, as well as the potential of the produced nanocomposite in targeted drug delivery, specific detection, and photoluminescence imaging. The fluorescence intensity of GOQD-CS-PEG was reduced due to transferred energy between (cytosine-guanin) base pairs in the hairpin structure of the aptamer, resulting in an "on/off" photoluminescence bio-sensing. Interestingly, the integration of pH-responsive chitosan nanoparticles in the nanocomposite results in a smart nanocomposite capable of delivering more curcumin to desired tumor cells. When selectively binds to the MUC-1 receptor, the two strands of aptamer separate in acidic conditions, resulting in a sustained drug release and photoluminescence recovery. The cytotoxicity results also revealed that the nanocomposite was more toxic to MUC-1-overexpressed tumor cells than to negative control cell lines, confirming its selective targeting. As a result, the proposed nanocomposite could be used as an intelligent cancer nanotheranostic platform for tracing MUC-1-overexpressed tumor cells and targeting them with great efficiency and selectivity.

Biocompatible mucoadhesive nanoparticles for brain targeting of ropinirole hydrochloride: Formulations, radiolabeling and biodistribution

Two nanoformulations with mucoadhesive properties and brain-targeting mechanisms were designed to deliver the anti-Parkinson's drug, ropinirole hydrochloride (RH). In the first formulation, RH and the amphiphilic block copolymer methoxy poly(ethylene glycol)-b-poly(caprolactone) were assembled in a core-shell morphology followed by coating with a mucoadhesive chitosan outer layer producing a multilayer vehicle (MLV). In the second formulation, RH was encapsulated during the polyelectrolyte complexation of two natural polymers, chitosan and alginate producing RH-loaded chitosan-alginate polyelectrolyte (PEC) nanocomplex. Conditions of each formulation were adopted for optimal drug loading. Physico-chemical characterization of the prepared formulations (particle size, polydispersity index and zeta-potential) exhibited stable monodispersed nanoparticles. RH was radiolabeled by I-131 radiotracer in a high-radiochemical yield. Biodistribution and brain targeting of RH from the prepared formulations were studied after administration of ¹³¹ I-RH-loaded nanoparticles to albino mice via intranasal and intravenous routs. Elevated brain radioactivity was detected post IN administration of (¹³¹ I-RH/PCL-PEG/CS) nanoparticles and (¹³¹ I-RH/CS-ALG) nanoparticles comparing with the IN administrated RH solutions (C_max  = 2.8 ± 0.3, 2 ± 0.3, 0.93 ± 0.03% radioactivity/g, 1 h post administration, respectively). This demonstrated that a relatively high-brain targeting could be achieved via intranasal route of administration of RH-loaded nanoparticles. The proposed models are further potential for application to deliver many other brain-targeting therapeutics.

Antimicrobial Potential of Curcumin: Therapeutic Potential and Challenges to Clinical Applications

Curcumin is a bioactive compound that is extracted from Curcuma longa and that is known for its antimicrobial properties. Curcuminoids are the main constituents of curcumin that exhibit antioxidant properties. It has a broad spectrum of antibacterial actions against a wide range of bacteria, even those resistant to antibiotics. Curcumin has been shown to be effective against the microorganisms that are responsible for surgical infections and implant-related bone infections, primarily Staphylococcus aureus and Escherichia coli. The efficacy of curcumin against Helicobacter pylori and Mycobacterium tuberculosis, alone or in combination with other classic antibiotics, is one of its most promising antibacterial effects. Curcumin is known to have antifungal action against numerous fungi that are responsible for a variety of infections, including dermatophytosis. Candidemia and candidiasis caused by Candida species have also been reported to be treated using curcumin. Life-threatening diseases and infections caused by viruses can be counteracted by curcumin, recognizing its antiviral potential. In combination therapy with other phytochemicals, curcumin shows synergistic effects, and this approach appears to be suitable for the eradication of antibiotic-resistant microbes and promising for achieving co-loaded antimicrobial pro-regenerative coatings for orthopedic implant biomaterials. Poor water solubility, low bioavailability, and rapid degradation are the main disadvantages of curcumin. The use of nanotechnologies for the delivery of curcumin could increase the prospects for its clinical application, mainly in orthopedics and other surgical scenarios. Curcumin-loaded nanoparticles revealed antimicrobial properties against S. aureus in periprosthetic joint infections.

Mesoporous silica@chitosan@gold nanoparticles as "on/off" optical biosensor and pH-sensitive theranostic platform against cancer

A cancer nanotheranostic system was fabricated based on mesoporous silica@chitosan@gold (MCM@CS@Au) nanosystem targeted by aptamer toward the MUC-1 positive tumor cells. Subsequently, curcumin as an efficient herbal anticancer drug was first encapsulated into chitosan-triphosphate nanoparticles and then the resulted nanoparticle was loaded into the nanosystem (MCM@CS@Au-Apt). The nanosystem successful fabrication was approved at each synthesis step through FTIR, XRD, BET, DLS, FE-SEM, HRTEM, and fluorescence spectroscopy. Besides, the interaction between aptamer and curcumin was evaluated using full atomistic molecular dynamics simulations. The mechanism of curcumin release was likewise investigated through different kinetic models. Afterwards, the potential of the designed nanosystem in targeted imaging, and drug delivery was evaluated using fluorescence microscopy and flow cytometry. It was found that the energy transfer between the base pairs in the hairpin of double strands of DNA aptamer acts as a quencher for MCM@CS@Au fluorescence culminating in an "on/off" optical biosensor. On the other hand, the presence of pH-sensitive chitosan nanoparticles creates smart nanosystem to deliver more curcumin into the desired cells. Indeed, when the aptamer specifically binds to the MUC-1 receptor, its double strands separate under the low pH condition, leading to the drug release and the recovery of the fluorescence ("On" state). Based on the toxicity results, this nanosystem had more toxicity toward the MUC-1-positive tumor cells than MUC-1-negative cells, representing its selective targeting. Therefore, this nanosystem could be introduced as a smart anticancer nanotheranostic system for tracing particular biomarkers (MUC-1), non-invasive fluorescence imaging, and targeted curcumin delivery.

Combinatorial liposomes of berberine and curcumin inhibit biofilm formation and intracellular methicillin resistant Staphylococcus aureus infections and associated inflammation

The increase in drug-resistant strains of Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), has led to an increased rate of infection-related mortality. The emergence of drug resistance has rendered many antibiotics ineffective. The poor penetration and retention of antibiotics in mammalian cells lead to recurrent latent infections. Thus, there is an increasing need for biodegradable, non-toxic anti-infectives that are effective in treating MRSA infections. Phytochemicals such as berberine (BBR) and curcumin (CCR) have long been explored for their antibacterial activities, but their efficacy is often limited due to low bioavailability, water solubility, and poor cell penetration. When used in combination these antimicrobials did not show any synergistic effect against MRSA. Here, both of them were co-encapsulated in liposomes (BCL) and evaluated for biocompatibility, synergistic antimicrobial activity, intracellular infections, associated inflammation, and on biofilms formed by MRSA. Co-encapsulation of BBR and CCR in liposomes decreased their MICs by 87% and 96%, respectively, as compared to their free forms with a FICI of 0.13, indicating synergy between them. BCL inhibited the growth of MRSA and prevented biofilm formation better than free drugs. Co-culture studies showed that intracellular infection was reduced to 77% post BCL treatment. It also reduced the production of pro-inflammatory cytokines by macrophages following infection. The liposomes were found to be five times more efficient than clindamycin and can be used as a potential antimicrobial carrier against intracellular infections.

Anti-Candida Activity of Curcumin: A Systematic Review

Curcumin is one of the important natural compounds that is extracted from turmeric. This compound and its derivatives have numerous biological properties, including antioxidant, anticancer, anti-inflammatory, antimicrobial, and healing effects. Extensive research in various fields has been conducted on turmeric as it is widely used as a food additive. The significant antifungal activity is one of the major effects of curcumin. In this paper, recent studies on the effects of different forms of curcumin drug on the candidiasis were systematically examined and discussed. The data in this study were extracted from the articles and reports published in the Web of Science, Google Scholar, PubMed, and Scopus databases. After the preliminary investigation, relevant reports were selected and classified based on the incorporated formulation and purpose of the study. After a systematic discussion of the data, it was found that the use of medicinal forms based on nanoparticles can increase the absorption and target the controlled release of curcumin with a more effective role compared to other formulations. Consequently, it can be concluded that new methods of modern medicine can be employed to increase the efficacy of natural pharmaceutical compounds used in the past. In this regard, the present study analyzed the effect of curcumin against various Candida infections, using the recent data. It was found that applying a combination of drug formulation or the formulation of curcumin and its derivatives can be an effective strategy to overcome the medicine resistance in fungal infections, especially candidiasis.

Chitosan-coated PLGA nanoparticles for the nasal delivery of ropinirole hydrochloride: In vitro and ex vivo evaluation of efficacy and safety

Nose-to-brain delivery is an attractive route for direct drug delivery to the central nervous system (CNS), avoiding hepatic first-pass metabolism and solving blood-brain barrier passage issues. Therefore, the aim of the present study was the development of PLGA and PLGA/chitosan (chit) nanoparticles (NPs) with mucoadhesive properties, able to encapsulate ropinirole hydrochloride (RH), an anti-Parkinsonian dopaminergic agonist, and suitable to promote RH delivery across the nasal mucosa. NPs produced by nanoprecipitation showed spherical shape and a mean average size of 98.8 nm and 468.0 nm (PLGA and PLGA/chit, respectively). RH loaded PLGA/chit NPs showed a complete release of the drug in simulated nasal electrolyte solution (SNES) over the period of 24 h and increased the permeation of RH through sheep nasal mucosa by 3.22-fold in comparison to PLGA NPs. None of RH loaded NPs induced hemolysis in whole blood or the production of reactive oxygen species (ROS) in Raw 264.7 cells. On their turn, PLGA/chit NPs decreased cell viability of Raw 264.7 cells and Peripheral Blood Mononuclear Cells (PBMCs) in a concentration-dependent manner. These results revealed that, particularly PLGA/chit NPs, could be a valuable carrier for the delivery of RH to the CNS, opening a new path for Parkinson's disease therapy.

Improving the Functional Activities of Curcumin Using Milk Proteins as Nanocarriers

Curcumin is one of the most common spices worldwide. It has potential benefits, but its poor solubility and bioavailability have restricted its application. To overcome these problems, this study aimed to assess the efficacy of sodium caseinate (SC), α-lactalbumin (α-La), β-lactoglobulin (β-lg), whey protein concentrate (WPC) and whey protein isolate (WPI) as nanocarriers of curcumin. Furthermore, the antioxidant, anticancer and antimicrobial activities of the formed nanoparticles were examined. The physicochemical characteristics of the formed nanoparticles as well as the entrapment efficiency (%) and the in vitro behavior regarding the release of curcumin (%) were examined. The results showed that the formation of curcumin–milk protein nanoparticles enhanced both the entrapment efficiency and the in vitro behavior release of curcumin (%). Cur/β-lg nanoparticles had the highest antioxidant activity, while SC and WPC nanoparticles had the highest anticancer effect. The antimicrobial activity of the formed nanoparticles was much higher compared to curcumin and the native milk proteins.

Preparation and antibiofilm studies of curcumin loaded chitosan nanoparticles against polymicrobial biofilms of Candida albicans and Staphylococcus aureus

Polymicrobial biofilms related infections are an important clinical problem with classical antibiotics being not sufficient in therapy. Here, curcumin (Cur) was loaded on positively charged chitosan nanoparticles (CSNP). The antibiofilm activities against mono- and polymicrobial biofilms of Candida albicans and Staphylococcus aureus were evaluated. The average diameter of CSNP-Cur was 134.37 ± 1.99 nm and its surface charge was +18.10 ± 0.82 mV. Cur released from NPs was slower at pH 7.4 than at pH 5.4. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to observe biofilm architecture and live/dead organisms within biofilm on medical silicone surface. CSNP-Cur exhibited excellent antibiofilm activity against planktonic bacteria or fungi, mono- and polymicrobial biofilm formations and preformed biofilms. SEM and CLSM showed that CSNP-Cur was able to reduce biofilm thickness as well as kill microbial cells embedded in biofilm on silicone surfaces.

Anti-microbial activity of curcumin nanoformulations: New trends and future perspectives

Curcumin has been used in numerous anti-microbial research because of its low side effects and extensive traditional applications. Despite having a wide range of effects, the intrinsic physicochemical characteristics such as low bioavailability, poor water solubility, photodegradation, chemical instability, short half-life and fast metabolism of curcumin derivatives limit their pharmaceutical importance. To overcome these drawbacks and improve the therapeutic ability of curcuminoids, novel approaches have been attempted recently. Nanoparticulate drug delivery systems can increase the efficiency of curcumin in several diseases, especially infectious diseases. These innovative strategies include polymeric nanoparticles, hydrogels, nanoemulsion, nanocomposite, nanofibers, liposome, nanostructured lipid carriers (NLCs), polymeric micelles, quantum dots, polymeric blend films and nanomaterial-based combination of curcumin with other anti-bacterial agents. Integration of curcumin in these delivery systems has displayed to improve their solubility, bioavailability, transmembrane permeability, prolong plasma half-life, long-term stability, target-specific delivery and upgraded the therapeutic effects. In this review paper, a range of in vitro and in vivo studies have been critically discussed to explore the therapeutic viability and pharmaceutical significance of the nano-formulated delivery systems to elevate the anti-bacterial activities of curcumin and its derivatives.

Formulation, stability study and preclinical evaluation of a vaginal cream containing curcumin in a rat model of vulvovaginal candidiasis

Owing to the growing resistance among isolates of Candida species to usual antifungal agents and the well-known therapeutic potential of curcumin, the purpose of this study was to develop and validate a vaginal formulation containing this substance and to evaluating its effectiveness in the treatment of experimental vulvovaginal candidiasis. Curcumin was incorporated in a vaginal cream in three concentrations (0.01%, 0.1% and 1.0%). The different concentrations of the cream and its controls were intravaginally administered in an immunosuppressed rat model to evaluate the efficacy in the treatment of experimental vulvovaginal candidiasis. Samples of the cream were also subjected to centrifugation and physical stability tests and an analytical method for quantification of curcumin was validated based on HPLC. The formulation was stable and the HPLC method could be considered suitable for the quantitative determination of curcumin in the cream. After 6 days of preclinical study, the number of infected animals was 1/6 in all groups treated with curcumin vaginal cream and the fungal burden showed a progressive reduction. Reduction in the inflammatory infiltrate was observed in the group treated with 1.0% cream. Vaginal cream containing curcumin could be considered a promising effective antifungal medicine in the treatment of vulvovaginal candidiasis.

Cefepime loaded O-carboxymethyl chitosan microspheres with sustained bactericidal activity and enhanced biocompatibility

Cefepime (CFP) is a frequently used antibiotic for prevention of post-surgery infection. Systemic delivery of CFP in a bulk dose usually shows effective therapeutic effects, while cytotoxicity can also be generated. To avoid the drawback of systemic delivery of antibiotic, local and controlled administration of drug is being employed to prolong therapeutic effects and reduce cytotoxicity by sustaining drug release and minimizing drug exposure. In this work, CFP loaded polymer O-carboxymethyl chitosan (OCMC) microspheres (CFP-OCMC-MPs) were fabricated and their antimicrobial activity against Staphylococcus aureus as well as biocompatibility were evaluated. The microspheres possessed the spherical surface with diameter approximately 7 μm. Fourier transforms infrared spectral and wide-angle X-ray diffraction analysis showed that CFP was steadily incorporated. The drug loading content and encapsulation efficiency of the microspheres were 21.4 ± 0.5% and 42.3 ± 0.7%, respectively. The drug release profiles were found to be biphasic with an initial burst release followed by a gradual release phase, following the Higuchi model. In addition, the CFP-OCMC-MPs were able to kill all the bacteria cultured in suspension within 24 h and exhibited long-lasting bactericidal activity as demonstrated by inhibition zone study. Compared to CFP, CFP-OCMC-MPs showed a milder toxicity toward osteoblast-like cells over an 8 day period. All these results suggest that CFP-OCMC-MPs are endowed with sustained treatment of bacterial infection and enhanced biocompatibility.