Polyherbal drug loaded starch nanoparticles as promising drug delivery system: Antimicrobial, antibiofilm and neuroprotective studies

Upcycling of industrial pea starch by rapid spray nanoprecipitation to develop plant-derived oil encapsulated starch nanoparticles for potential agricultural applications

Starch is one of the natural encapsulant materials widely used in food, pharmaceutical and cosmetic industries. Starch with high amylose content (above 40 %, w/w) is prone to form single helices V-type allomorph with a hydrophilic outer surface and a hydrophobic inner cavity making them suitable for encapsulation of hydrophobic compounds such as essential oils, fatty acids, and vitamins. Pea starch obtained from pea protein processing industries have a high amylose content (40 %, w/w) rendering them unsuitable for direct food applications as ingredients. Therefore, in this study, an in-house spraying procedure was used to synthesize nanoparticles using pea starch, to encapsulate neem oil, a natural antimicrobial compound obtained from neem plant (Azadirachta indica) seed. The synthesis of the oil-encapsulated starch nanoparticles (OESNP) was optimized using a Box-Behnken experimental design to study the influence of the processing parameters such as the initial starch concentration, homogenization speed, duration of homogenization, sample injection rate, and quantity of antisolvent (ethanol). The optimized sample showed an 80-90 % encapsulation efficiency and particle size of <500 nm. The spherical OESNPs also demonstrated sustained release of the oil compared to free oil when dispersed in water. X-ray diffraction analysis revealed the coexistence of C-type and V-type polymorphs in the loaded and unloaded nanoparticles. It is concluded that the synthesized OESNPs with controlled release hold the potential to utilize industrial pea starch waste for the delivery of natural pesticides in agriculture.

Thermoplastic Starch with Maltodextrin: Preparation, Morphology, Rheology, and Mechanical Properties

This work describes the preparation of highly homogeneous thermoplastic starches (TPS's) with the addition of 0, 5, or 10 wt.% of maltodextrin (MD) and 0 or 3 wt.% of TiO2 nanoparticles. The TPS preparation was based on a two-step preparation protocol, which consisted in solution casting (SC) followed by melt mixing (MM). Rheology measurements at the typical starch processing temperature (120 °C) demonstrated that maltodextrin acted as a lubricating agent, which decreased the viscosity of the system. Consequently, the in situ measurement during the MM confirmed that the torque moments and real processing temperatures of all TPS/MD systems decreased in comparison with the pure TPS. The detailed characterization of morphology, thermomechanical properties, and local mechanical properties revealed that the viscosity decrease was accompanied by a slight decrease in the system homogeneity. The changes in the real processing temperatures might be quite moderate (ca 2-3 °C), but maltodextrin is a cheap and easy-to-add modifier, and the milder processing conditions are advantageous for both technical applications (energy savings) and biomedical applications (beneficial for temperature-sensitive additives, such as antibiotics).

Fishwaste Derived Hydroxyapatite Nanostructure Combined with Black Rice Wine for Potential Antioxidant and Antimicrobial Response

Hospital-acquired infection remains a serious threat globally, due to development of resistance to conventional antibiotics, which necessitates the urge for alternative therapy. Green nanotechnology has emerged as a holistic approach to address antibiotic resistance by combining environmental sustainability with improved therapeutic outcome. Nanostructure hydroxyapatite (HAP) has received significant attention in therapeutic and regenerative purposes due to its porous scaffold structure and biocompatible nature. In the present study, hydroxyapatite (HAP) nanoparticle was fabricated from the fish scale waste of red snapper fish. Black rice wine (BRW) was extracted from black rice commonly termed as Karupu kavuni/forbidden rice known for its nutritious effects. The present study focused on encapsulation of BRW within HAP nanoparticles (HAP@BRW) and evaluated its potential against nosocomial infections. Spectral and microscopic characterization of HAP@BRW revealed uniform encapsulation of BRW in HAP nanoparticles, aggregated irregular-shaped morphology of size 117.6 nm. Maximum release of BRW (72%) within 24 h indicates HAP as suitable drug delivery system suitable for biomedical applications. Antimicrobial studies revealed that HAP@BRW exhibited potent bactericidal effect against MRSA, MSSA, and Pseudomonas aeruginosa. Furthermore, HAP@BRW significantly inhibited the biofilm forming ability of MSSA and P. aeruginosa. Rich antioxidant property of HAP@BRW might be due to the presence of rich source of total polyphenolic, flavonoid, and anthocyanin content in BRW. In vitro and in vivo toxicity studies revealed biocompatible nature of HAP@BRW. Antibiofilm, antimicrobial, antioxidant, and biocompatible nature of HAP@BRW makes it a promising candidate for coating medical implants to avoid implant-associated infections and nosocomial infections.

Withanolides production by the endophytic fungus Penicillium oxalicum associated with Withania somnifera (L.) Dunal

Withanolides are steroidal lactones with diverse bioactive potential and their production from plant sources varies with genotype, age, culture conditions, and geographical region. Endophytic fungi serve as an alternative source to produce withanolides, like their host plant, Withania somnifera (L.) Dunal. The present study aimed to isolate endophytic fungi capable of producing withanolides, characterization and investigation of biological activities of these molecules. The methanolic fungal crude extract of one of the fungal isolates WSE16 showed maximum withanolide production (219 mg/L). The fungal isolate WSE16 was identified as Penicillium oxalicum based on its morphological and internal transcribed spacer (ITS) sequence analysis and submitted in NCBI (accession number OR888725). The methanolic crude extract of P. oxalicum was further purified by column chromatography, and collected fractions were assessed for the presence of withanolides. Fractions F3 and F4 showed a higher content of withanolides (51.8 and 59.1 mg/L, respectively) than other fractions. Fractions F3 and F4 exhibited antibacterial activity against Staphylococcus aureus with an IC50 of 23.52 and 17.39 µg/ml, respectively. These fractions also showed antioxidant activity (DPPH assay with IC50 of 39.42 and 38.71 µg/ml, superoxide anion scavenging assay with IC50 of 41.10 and 38.84 µg/ml, and reducing power assay with IC50 of 42.61 and 41.40 µg/ml, respectively) and acetylcholinesterase inhibitory activity (IC50 of 30.34 and 22.05 µg/ml, respectively). The withanolides present in fraction 3 and fraction 4 were identified as (20S, 22R)-1a-Acetoxy-27-hydroxywitha-5, 24-dienolide-3b-(O-b-D-glucopyranoside) and withanamide A, respectively, using UV, FTIR, HRMS, and NMR analysis. These results suggest that P. oxalicum, an endophytic fungus isolated from W. somnifera, is a potential source for producing bioactive withanolides.

Nitric oxide-releasing thiolated starch nanoparticles embedded in gelatin sponges for wound dressing applications

This study introduces a novel wound dressing by combining nitric oxide-releasing thiolated starch nanoparticles (NO-TS NPs) with gelatin. First, starch was thiolated (TS), and then its nanoparticles were prepared (TS NPs). Subsequently, NPs were covalently bonded to sodium nitrite to obtain NO-releasing TS NPs (NO-TS-NPs) that were incorporated into gelatin sponges at various concentrations. The resulting spherical TS NPs had a mean size of 85.42 ± 5.23 nm, which rose to 100.73 ± 7.41 nm after bonding with sodium nitrite. FTIR spectroscopy confirmed S-nitrosation on the NO-TS NPs' surface, and morphology analysis showed well-interconnected pores in all sponges. With higher NO-TS NPs content, pore size, porosity, and water uptake increased, while compressive modulus and strength decreased. Composites exhibited antibacterial activity, particularly against E. coli, with enhanced efficacy at higher NPs' concentrations. In vitro release studies demonstrated Fickian diffusion, with faster NO release in sponges containing more NPs. The released NO amounts were non-toxic to fibroblasts, but samples with fewer NO-TS NPs exhibited superior cellular density, cell attachment, and collagen secretion. Considering the results, including favorable mechanical strength, release behavior, antibacterial and cellular properties, gelatin sponges loaded with 2 mg/mL of NO-TS NPs can be suitable for wound dressing applications.

Preparation and characterization of pH-sensitive chitosan/starch/MoS2 nanocomposite for control release of curcumin macromolecules drug delivery; application in the breast cancer treatment

In this work, chitosan (CS), Starch (S), and Molybdenum Disulfide (MoS2) were combined to create a nanocarrier that was utilized to treat breast cancer using the MCF-7 cell line. To analyze the features of the nanocarrier, Fourier-transform infrared spectroscopy (FTIR) and X-Ray diffraction (XRD) tests were performed, respectively, to discover physical interactions and chemical bonding. Field emission scanning electron microscopy (FE-SEM), Dynamic light scattering (DLS), and zeta potential analyses were performed and reported to determine the structural characteristics and morphology of nanoparticles, size distribution, and surface charge of nanocarriers, respectively. The average size of the nanocomposite was measured at around 279 nm, and the surface charge of the nanocarrier was determined to be +86.31 mV. The entrapment and drug loading efficiency of nanocarriers were 87.25 % and 46.5 %, respectively, which is an acceptable value. The kinetics and release mode of the drug were investigated, and it was found that the synthesized nanocarrier was sensitive to pH and that its release was stable. The amount of the nanocarriers' toxicity and cell death were evaluated using MTT tests and flow cytometry, respectively. In the present study, the nanocarrier was wholly nontoxic and had anticancer properties against the MCF-7 cell line. This nanocarrier is very important due to its non-toxicity and sensitivity to pH and can be used in drug delivery and medical applications.

Advances in Starch Nanoparticle for Emulsion Stabilization

Starch nanoparticles (SNPs) are generally defined as starch grains smaller than 600-1000 nm produced from a series of physical, chemical, or biologically modified starches. Many studies have reported the preparation and modification of SNPs, which are mostly based on the traditional "top-down" strategy. The preparation process generally has problems with process complexity, long reaction periods, low yield, high energy consumption, poor repeatability, etc. A "bottom-up" strategy, such as an anti-solvent method, is proven to be suitable for the preparation of SNPs, and they are synthesized with small particle size, good repeatability, a low requirement on equipment, simple operation, and great development potential. The surface of raw starch contains a large amount of hydroxyl and has a high degree of hydrophilicity, while SNP is a potential emulsifier for food and non-food applications.

Regenerative marine waste towards CaCO3 nanoformulation for Alzheimer's therapy

Alzheimer's disorder (AD) is associated with behavioural and cognitive destruction with due respect to the neurological degeneration. Conventional therapeutic approach for treatment of AD using neuroprotective drugs suffered certain limitations such as poor solubility, insufficient bioavailability, adverse side effects at higher dose and ineffective permeability on blood brain barrier (BBB). Development of nanomaterial based drug delivery system helped to overcome these barriers. Hence the present work focused on encapsulating neuroprotective drug citronellyl acetate within CaCO₃ nanoparticles to develop neuroprotective CaCO₃ nanoformulation (CA@CaCO₃ NFs). CaCO₃ was derived from marine conch shell waste, while the neuroprotective drug citronellyl acetate was scrutinized by in-silico high throughput screening. In-vitro findings revealed that CA@CaCO₃ nanoformulation exhibited enhanced free radical scavenging activity of 92% (IC₅₀ value - 29.27 ± 2.6 μg/ml), AChE inhibition of 95% (IC₅₀ value - 25.6292 ± 1.5 μg/ml) at its maximum dose (100 μg/ml). CA@CaCO₃ NFs attenuated the aggregation of β-amyloid peptide (Aβ) and also disaggregated the preformed mature plaques the major risk factor for AD. Overall, the present study reveals that CaCO₃ nanoformulations exhibits potent neuroprotective potential when compared to the CaCO₃ nanoparticles alone and citronellyl acetate alone due to the sustained drug release and synergistic effect of CaCO₃ nanoparticles and citronellyl acetate depicting the fact that CaCO₃ can act as promising drug delivery system for treatment of neurodegenerative and CNS related disorders.

Essential characteristics improvement of metallic nanoparticles loaded carbohydrate polymeric films - A review

Petroleum-based films have contributed immensely to various environmental issues. Developing green-based films from carbohydrate polymers is crucial for addressing the harms encountered. However, some limitations exist on their property, processibility, and applicability that prohibit their processing for further developments. This review discusses the potential carbohydrate polymers and their sources, film preparation methods, such as solvent-casting, tape-casting, extrusion, and thermo-mechanical compressions for green-based films using various biological polymers with their merits and demerits. Research outcomes revealed that the essential characteristics improvement achieved by incorporating different metallic nanoparticles has significantly reformed the properties of biofilms, including crystallization, mechanical stability, thermal stability, barrier function, and antimicrobial activity. The property-enhanced bio-based films made with nanoparticles are potentially interested in replacing fossil-based films in various areas, including food-packaging applications. The review paves a new way for the commercial use of numerous carbohydrate polymers to help maintain a sustainable green environment.

Novel amphiphilic hydroxyethyl starch-based nanoparticles loading camptothecin exhibit high anticancer activity in HepG2 cells and zebrafish

Camptothecin is a naturally occurred anticancer drug but exhibits limitations including poor aqueous solubility, low bioavailability, and high level of adverse drug reactions on normal organs. To overcome these problems, this paper developed a novel amphiphilic Lau-Leu-HES carrier using hydroxyethyl starch, lauric acid, and L-leucine as starting materials. The carrier was successfully applied to prepare Lau-Leu-HES nanoparticles loading camptothecin. The drug loading efficiency and encapsulation efficiency of the nanoparticles were calculated to be 29.04% and 81.85%, respectively. The nanoparticles exhibited high zeta potential (-15.51 mV) and small hydrodynamic diameter (105.4 nm). Camptothecin in nanoparticles could be rapidly released under acidic condition (pH = 4.5), thereby indicating the high sensitivity under cancer microenvironments. Anticancer investigation revealed that the nanoparticles could inhibit the proliferation of HepG2 cells in vitro. Compared with commercial available drug doxorubicin, the nanoparticles could significantly inhibit the expression of kras^v12 oncogene in transgenic Tg (EGFP-kras^V12) zebrafish. These results indicate that the camptothecin-loaded Lau-Leu-HES nanoparticles are expected to be a potential candidate for cancer therapy.

Biodegradable Biopolymeric Nanoparticles for Biomedical Applications-Challenges and Future Outlook

Biopolymers are polymers obtained from either renewable or non-renewable sources and are the most suitable candidate for tailor-made nanoparticles owing to their biocompatibility, biodegradability, low toxicity and immunogenicity. Biopolymeric nanoparticles (BPn) can be classified as natural (polysaccharide and protein based) and synthetic on the basis of their origin. They have been gaining wide interest in biomedical applications such as tissue engineering, drug delivery, imaging and cancer therapy. BPn can be synthesized by various fabrication strategies such as emulsification, ionic gelation, nanoprecipitation, electrospray drying and so on. The main aim of the review is to understand the use of nanoparticles obtained from biodegradable biopolymers for various biomedical applications. There are very few reviews highlighting biopolymeric nanoparticles employed for medical applications; this review is an attempt to explore the possibilities of using these materials for various biomedical applications. This review highlights protein based (albumin, gelatin, collagen, silk fibroin); polysaccharide based (chitosan, starch, alginate, dextran) and synthetic (Poly lactic acid, Poly vinyl alcohol, Poly caprolactone) BPn that has recently been used in many applications. The fabrication strategies of different BPn are also being highlighted. The future perspective and the challenges faced in employing biopolymeric nanoparticles are also reviewed.

Starches in the encapsulation of plant active ingredients: state of the art and research trends

As a natural polymer, starches and their derivatives have received widespread attention in the cosmetic and pharmaceutical industries, particularly for their use as a coating material. In this sense, as an encapsulating agent, starches stand out, considering the number of compounds that they can trap. Additionally, they provide a nutritional contribution and may improve acceptance by patients. As such, this type of material may serve as an alternative to overcome gaps such as loss of activity of the active principles, low assimilation, or deterioration under environmental and physiological conditions. In this paper, we aim to present the state of the art and research trends on the use of starch as a wall material for the encapsulation of active principles of plant origin. It was found that the most-encapsulated active principles are essential oils and polyphenols; native or modified starches are typically used, either as the sole wall material or in combination with other polymers; and the most widely used methodology is spray drying. The reviewed studies indicate the potential of starches for their use in active ingredient encapsulation processes, improving their viability and expanding their range of applications in different industries, as well as showing a clearly increasing publication trend over the last 10 years.

Graphical abstract

Starch Nanoparticles: Preparation, Properties and Applications

Starch as a natural polymer is abundant and widely used in various industries around the world. In general, the preparation methods for starch nanoparticles (SNPs) can be classified into 'top-down' and 'bottom-up' methods. SNPs can be produced in smaller sizes and used to improve the functional properties of starch. Thus, they are considered for the various opportunities to improve the quality of product development with starch. This literature study presents information and reviews regarding SNPs, their general preparation methods, characteristics of the resulting SNPs and their applications, especially in food systems, such as Pickering emulsion, bioplastic filler, antimicrobial agent, fat replacer and encapsulating agent. The aspects related to the properties of SNPs and information on the extent of their utilisation are reviewed in this study. The findings can be utilised and encouraged by other researchers to develop and expand the applications of SNPs.

Exploring Possible Ways to Enhance the Potential and Use of Natural Products through Nanotechnology in the Battle against Biofilms of Foodborne Bacterial Pathogens

Biofilms enable pathogenic bacteria to survive in unfavorable environments. As biofilm-forming pathogens can cause rapid food spoilage and recurrent infections in humans, especially their presence in the food industry is problematic. Using chemical disinfectants in the food industry to prevent biofilm formation raises serious health concerns. Further, the ability of biofilm-forming bacterial pathogens to tolerate disinfection procedures questions the traditional treatment methods. Thus, there is a dire need for alternative treatment options targeting bacterial pathogens, especially biofilms. As clean-label products without carcinogenic and hazardous potential, natural compounds with growth and biofilm-inhibiting and biofilm-eradicating potentials have gained popularity as natural preservatives in the food industry. However, the use of these natural preservatives in the food industry is restricted by their poor availability, stability during food processing and storage. Also there is a lack of standardization, and unattractive organoleptic qualities. Nanotechnology is one way to get around these limitations and as well as the use of underutilized bioactives. The use of nanotechnology has several advantages including traversing the biofilm matrix, targeted drug delivery, controlled release, and enhanced bioavailability, bioactivity, and stability. The nanoparticles used in fabricating or encapsulating natural products are considered as an appealing antibiofilm strategy since the nanoparticles enhance the activity of the natural products against biofilms of foodborne bacterial pathogens. Hence, this literature review is intended to provide a comprehensive analysis of the current methods in nanotechnology used for natural products delivery (biofabrication, encapsulation, and nanoemulsion) and also discuss the different promising strategies employed in the recent and past to enhance the inhibition and eradication of foodborne bacterial biofilms.

Sustainable Biodegradable Biopolymer-Based Nanoparticles for Healthcare Applications

Biopolymeric nanoparticles are gaining importance as nanocarriers for various biomedical applications, enabling long-term and controlled release at the target site. Since they are promising delivery systems for various therapeutic agents and offer advantageous properties such as biodegradability, biocompatibility, non-toxicity, and stability compared to various toxic metal nanoparticles, we decided to provide an overview on this topic. Therefore, the review focuses on the use of biopolymeric nanoparticles of animal, plant, algal, fungal, and bacterial origin as a sustainable material for potential use as drug delivery systems. A particular focus is on the encapsulation of many different therapeutic agents categorized as bioactive compounds, drugs, antibiotics, and other antimicrobial agents, extracts, and essential oils into protein- and polysaccharide-based nanocarriers. These show promising benefits for human health, especially for successful antimicrobial and anticancer activity. The review article, divided into protein-based and polysaccharide-based biopolymeric nanoparticles and further according to the origin of the biopolymer, enables the reader to select the appropriate biopolymeric nanoparticles more easily for the incorporation of the desired component. The latest research results from the last five years in the field of the successful production of biopolymeric nanoparticles loaded with various therapeutic agents for healthcare applications are included in this review.

Nanotechnology as a tool to overcome macromolecules delivery issues

Nanocarriers can deliver drugs to specific organs or cells, potentially bridging the gap between a drug's function and its interaction with biological systems such as human physiology. The untapped potential of nanotechnology stems from its ability to manipulate materials, allowing control over physical and chemical properties and overcoming drug-related problems, e.g., poor solubility or poor bioavailability. For example, most protein drugs are administered parenterally, each with challenges and peculiarities. Some problems faced by bioengineered macromolecule drugs leading to poor bioavailability are short biological half-life, large size and high molecular weight, low permeability through biological membranes, and structural instability. Nanotechnology emerges as a promising strategy to overcome these problems. Nevertheless, the delivery system should be carefully chosen considering loading efficiency, physicochemical properties, production conditions, toxicity, and regulations. Moving from the bench to the bedside is still one of the major bottlenecks in nanomedicine, and toxicological issues are the greatest challenges to overcome. This review provides an overview of biotech drug delivery approaches, associated nanotechnology novelty, toxicological issues, and regulations.

Thermoplastic starch nanocomposites: sources, production and applications - a review

The development of materials based on thermoplastic starch (TPS) is an excellent alternative to replace or reduce the use of petroleum-derived polymers. The abundance, renewable origin, biodegradability, biocompatibility, and low cost of starch are among the advantages related to the application of TPS compared to other thermoplastic biopolymers. However, through the literature review, it was possible to observe the need to improve some properties, to allow TPS to replace commonly used polyolefins. The studies reviewed achieved these modifications were achieved by using plasticizers, adjusting processing conditions, and incorporating fillers. In this sense, the addition of nanofillers proved to be the main modification strategy due to the large number of available nanofillers and the low charge concentration required for such improvement. The improvement can be seen in thermal, mechanical, electrical, optical, magnetic, antimicrobial, barrier, biocompatibility, cytotoxicity, solubility, and swelling properties. These modification strategies, the reviewed studies described the development of a wide range of materials. These are products with great potential for targeting different applications. Thus, this review addresses a wide range of essential aspects in developing of this type of nanocomposite. Covering from starch sources, processing routes, characterization methods, the properties of the obtained nanocomposites, to the various applications. Therefore, this review will provide an overview for everyone interested in working with TPS nanocomposites. Through a comprehensive review of the subject, which in most studies is done in a way directed to a specific area of study.

Advances in Nanostructures for Antimicrobial Therapy

Microbial infections caused by a variety of drug-resistant microorganisms are more common, but there are fewer and fewer approved new antimicrobial chemotherapeutics for systemic administration capable of acting against these resistant infectious pathogens. Formulation innovations of existing drugs are gaining prominence, while the application of nanotechnologies is a useful alternative for improving/increasing the effect of existing antimicrobial drugs. Nanomaterials represent one of the possible strategies to address this unfortunate situation. This review aims to summarize the most current results of nanoformulations of antibiotics and antibacterial active nanomaterials. Nanoformulations of antimicrobial peptides, synergistic combinations of antimicrobial-active agents with nitric oxide donors or combinations of small organic molecules or polymers with metals, metal oxides or metalloids are discussed as well. The mechanisms of actions of selected nanoformulations, including systems with magnetic, photothermal or photodynamic effects, are briefly described.

Application of starch-based nanoparticles and cyclodextrin for prebiotics delivery and controlled glucose release in the human gut: a review

Starches are a major constituent of staple foods and are the main source of energy in the human diet (55-70%). In the gastrointestinal tract, starches are hydrolyzed into glucose by α-amylase and α-glucosidase, which leads to a postprandial glucose elevation. High levels of blood glucose levels over sustained periods may promote type 2 diabetes mellitus (T2DM) and obesity. Increasing consumption of starchy foods with a lower glycemic index may therefore contribute to improved health. In this paper, the preparation and properties of several starch-based nanoparticles (SNPs) and cyclodextrins (CDs) derivatives are reviewed. In particular, we focus on the various mechanisms responsible for the ability of these edible nanomaterials to modulate glucose release and the gut microbiome in the gastrointestinal tract. The probiotic functions are achieved through encapsulation and protection of prebiotics or bioactive components in foods or the human gut. This review therefore provides valuable information that could be used to design functional foods for improving human health and wellbeing.

Synthesis, characteristics, and applications of modified starch nanoparticles: A review

Nowadays, starch nanoparticles (SNPs) are drawing attention to the scientific community due to their versatility and wide range of applications. Although several works have extensively addressed the SNP production routes, not much is discussed about the SNPs modification techniques, as well as the use of modified SNPs in typical and unconventional applications. Here, we focused on the SNP modification strategies and characteristics and performance of the resulting products, as well as their practical applications, while pointing out the main limitations and recommendations. We aim to guide researchers by identifying the next steps in this emerging line of research. SNPs esterification and oxidation are preferred chemical modifications, which result in changes in the functional groups. Moreover, additional polymers are incorporated into the SNP surface through copolymer grafting. Physical modification of starch has demonstrated similar changes in the functional groups without the need for toxic chemicals. Modified SNPs rendered differentiated properties, such as size, shape, crystallinity, hydrophobicity, and Zeta-potential. For multiple applications, tailoring the aforementioned properties is key to the performance of nanoparticle-based systems. However, the number of studies focusing on emerging applications is fairly limited, while their applications as drug delivery systems lack in vivo studies. The main challenges and prospects were discussed.

Multifunctional applications of natural polysaccharide starch and cellulose: An update on recent advances

The emergence of clinical complications and therapeutic challenges for treating various diseases necessitate the discovery of novel restorative functional materials. Polymer-based drug delivery systems have been extensively reported in the last two decades. Recently, there has been an increasing interest in the progression of natural biopolymers based controlled therapeutic strategies, especially in drug delivery and tissue engineering applications. However, the solubility and functionalisation due to their complex network structure and intramolecular bonding seem challenging. This review explores the current advancement and prospects of the most promising natural polymers such as cellulose, starch and their derivatives-based drug delivery vehicles like hydrogels, films and composites, in combating major ailments such as bone infections, microbial infections, and cancers. In addition, selective drug targeting using metal-drug (MD) and MD-based polymeric missiles have been exciting but challenging for its application in cancer therapeutics. Owing to high biocompatibility of starch and cellulose, these materials have been extensively evaluated in biomedical and pharmaceutical applications. This review presents a detailed impression of the current trends for the construction of biopolymer-based tissue engineering, drug/gene/protein delivery vehicles.

Plant-derived nanotherapeutic systems to counter the overgrowing threat of resistant microbes and biofilms

Since antiquity, the survival of human civilization has always been threatened by the microbial infections. An alarming surge in the resistant microbial strains against the conventional drugs is quite evident in the preceding years. Furthermore, failure of currently available regimens of antibiotics has been highlighted by the emerging threat of biofilms in the community and hospital settings. Biofilms are complex dynamic composites rich in extracellular polysaccharides and DNA, supporting plethora of symbiotic microbial life forms, that can grow on both living and non-living surfaces. These enforced structures are impervious to the drugs and lead to spread of recurrent and non-treatable infections. There is a strong realization among the scientists and healthcare providers to work out alternative strategies to combat the issue of drug resistance and biofilms. Plants are a traditional but rich source of effective antimicrobials with wider spectrum due to presence of multiple constituents in perfect synergy. Other than the biocompatibility and the safety profile, these phytochemicals have been repeatedly proven to overcome the non-responsiveness of resistant microbes and films via multiple pathways such as blocking the efflux pumps, better penetration across the cell membranes or biofilms, and anti-adhesive properties. However, the unfavorable physicochemical attributes and stability issues of these phytochemicals have hampered their commercialization. These issues of the phytochemicals can be solved by designing suitably constructed nanoscaled structures. Nanosized systems can not only improve the physicochemical features of the encapsulated payloads but can also enhance their pharmacokinetic and therapeutic profile. This review encompasses why and how various types of phytochemicals and their nanosized preparations counter the microbial resistance and the biofouling. We believe that phytochemical in tandem with nanotechnological innovations can be employed to defeat the microbial resistance and biofilms. This review will help in better understanding of the challenges associated with developing such platforms and their future prospects.

Polymer-Based Nanosystems-A Versatile Delivery Approach

Polymer-based nanoparticles of tailored size, morphology, and surface properties have attracted increasing attention as carriers for drugs, biomolecules, and genes. By protecting the payload from degradation and maintaining sustained and controlled release of the drug, polymeric nanoparticles can reduce drug clearance, increase their cargo's stability and solubility, prolong its half-life, and ensure optimal concentration at the target site. The inherent immunomodulatory properties of specific polymer nanoparticles, coupled with their drug encapsulation ability, have raised particular interest in vaccine delivery. This paper aims to review current and emerging drug delivery applications of both branched and linear, natural, and synthetic polymer nanostructures, focusing on their role in vaccine development.

Characterization of alginate extracted from Sargassum latifolium and its use in Chlorella vulgaris growth promotion and riboflavin drug delivery

Alginates derived from macroalgae have been widely used in a variety of applications due to their stability, biodegradability and biocompatibility. Alginate was extracted from Egyptian Sargassum latifolium thallus yielding 17.5% w/w. The chemical composition of S. latifolium is rich in total sugars (41.08%) and uronic acids (47.4%); while, proteins, lipids and sulfates contents are 4.61, 1.13 and 0.09%, respectively. NMR, FTIR and TGA analyses were also performed. Crystallinity index (0.334) indicates alginate semicrystalline nature. Sodium alginate hydrolysate was evaluated as Chlorella vulgaris growth promoter. The highest stimulation (0.7 g/L biomass) was achieved by using 0.3 g/L alginate hydrolysate supplementation. The highest total soluble proteins and total carbohydrates were 179.22 mg/g dry wt and 620.33 mg/g dry wt, respectively. The highest total phenolics content (27.697 mg/g dry wt.), guaiacol peroxidase activity (2.899 µmol min-1 g-1) were recorded also to 0.3 g/L alginate hydrolysate supplementation. Riboflavin-entrapped barium alginate-Arabic gum polymeric matrix (beads) was formulated to achieve 89.15% optimum drug entrapment efficiency (EE%). All formulations exhibited prolonged riboflavin release over 120 min in simulated gastric fluid, followed Higuchi model (R2 = 0.962-0.887) and Korsmeyer-Peppas model with Fickian release (n ranges from 0.204 to 0.3885).

Antibiofilm and antimicrobial efficacy evaluation of polypyrrole nanotubes embedded in aminated gum acacia based nanocomposite

The sustainable development of natural polysaccharide-based hybrid composites is highly important for the effective replacement of metal nanoparticles in diverse applications. Here, polypyrrole nanotubes (PPyNTs) were embedded on the surface of aminated gum acacia (AGA) to produce ecofriendly nanocomposites for biomedical applications. The morphology of a PPyNT-enhanced AGA (PPyNT@AGA) hybrid nanocomposite was studied by scanning electron microscopy and transmission electron microscopy and their affirmed interactions were characterised by X-ray diffraction, Raman, Fourier transform-infrared and UV-visible spectroscopy. Interestingly, the prepared PPyNT@AGA nanocomposite exhibited 90% biofilm inhibition against gram-negative Pseudomonas aeruginosa, gram-positive Streptococcus pneumoniae and fungal strain Candida albicans with promising antimicrobial performance. This study establishes the good inhibition of a PPyNT@AGA hybrid composite against various microorganisms. The stability of the nanocomposite coupled with antimicrobial activity enables an effective strategy for diagnosing and controlling pathogens.

Synthesis, characterization, and cytotoxicity of starch-encapsulated biogenic silver nanoparticle and its improved anti-bacterial activity

The present work reported synthesis, characterization, and biocompatibility of starch encapsulated silver nanoparticles (St-PF-AgNPs) and their antibacterial activity. The synthesis of St-PF-AgNPs involved in two steps: (i) synthesis of the biogenic silver nanoparticles using the fungal extracts (PF-AgNPs); and, (ii) encapsulation of starch in PF-AgNPs (St-PF-AgNPs). The surface plasmon resonance was found at 420 nm for the PF-AgNPs while it was at 260 and 420 nm for the St-PF-AgNPs. FTIR spectrum demonstrated the capping and encapsulation of the fungal extracts and starch in PF-AgNPs and St-PF-AgNPs. The XRD and TEM-EDS confirmed the crystalline nature, spherical-shaped , and polydispersed- PF-AgNPs and St-PF-AgNPs with strong signals of Ag. The St-PF-AgNPs showed a Z-average size of 115.2 d.nm and zeta potential of -17.8 (mV) as indicated by DLS and zeta potentials. The cytotoxicity results demonstrated higher toxicity of PF-AgNPs than St-PF-AgNPs in HEK293 cells. The antibacterial activity of St-PF-AgNPs were higher than PF-AgNPs in S. aureus. Overall, this work concluded that the starch encapsulation significantly increased the antibacterial activity of PF-AgNPs and this opens a new avenue for the treatment of bacterial infections through the sustained release of PF-AgNPs to target pathogenic bacterial cells.

Synthesis of Starch Nanoparticles and Their Applications for Bioactive Compound Encapsulation

In recent years, starch nanoparticles (SNPs) have attracted growing attention due to their unique properties as a sustainable alternative to common nanomaterials since they are natural, renewable and biodegradable. SNPs can be obtained by the breakdown of starch granules through different techniques which include both physical and chemical methods. The final properties of the SNPs are strongly influenced by the synthesis method used as well as the operational conditions, where a controlled and monodispersed size is crucial for certain bioapplications. SNPs are considered to be a good vehicle to improve the controlled release of many bioactive compounds in different research fields due to their high biocompatibility, potential functionalization, and high surface/volume ratio. Their applications are frequently found in medicine, cosmetics, biotechnology, or the food industry, among others. Both the encapsulation properties as well as the releasing processes of the bioactive compounds are highly influenced by the size of the SNPs. In this review, a general description of the different types of SNPs (whole and hollow) synthesis methods is provided as well as on different techniques for encapsulating bioactive compounds, including direct and indirect methods, with application in several fields. Starches from different botanical sources and different bioactive compounds are compared with respect to the efficacy in vitro and in vivo. Applications and future research trends on SNPs synthesis have been included and discussed.

Mung bean (Vigna radiata) porous starch for solubility and dissolution enhancement of poorly soluble drug by solid dispersion

In this study, a novel Vigna radiata based porous starch (PS) is prepared by solvent exchange technique and explored as a solubilizer for model drug albendazole (ABZ). PS carrier was investigated for different chemical, functional, and micromeritic properties. Solubilizing potential of PS is evaluated by formulating ABZ-PS solid dispersion (1:0.5-1:2) based tablets (SDT). ABZ-PS solid dispersions were evaluated for micromeritic properties, dissolution studies, and anthelmintic activity. Direct compression suitability and susceptibility of mung bean starch were studied by SeDem diagram, Heckel, and Kawakita analysis respectively. PS had an A-type crystallinity pattern and evinced functional properties similar to other legume starches. PS was determined to be suitable for direct compression (good compressibility index = 5.50). SD (1:2) manifested 36.18 fold and 1.6-3.04 fold improvement in the % dissolution and anthelmintic activity of ABZ respectively. All SD batches (R² = 0.949-0.996) and ABZ (R² = 0.168) followed the Higuchi-matrix release kinetic model. DSC and P-XRD analysis corroborated the amorphous form of ABZ. SDT showed ≈ a 1.90 fold improvement in dissolution rate than the marketed formulation. Conclusively, Vigna radiata PS could be explored as an alternative to reduce the large burden on the established starches.

Exploring the potential of chitosan-based particles as delivery-carriers for promising antimicrobial glycolipid biosurfactants

Driven by the need to find alternatives to control Staphylococcus aureus infections, this work describes the development of chitosan-based particulate systems as carriers for antimicrobial glycolipids. By using a simple ionic gelation method stable nanoparticles were obtained showing an encapsulation efficiency of 41.1 ± 8.8 % and 74.2 ± 1.3 % and an average size of 210.0 ± 15.7 nm and 329.6 ± 8.0 nm for sophorolipids and rhamnolipids chitosan-nanoparticles, respectively. Glycolipids incorporation and particle size was correspondingly corroborated by FTIR-ATR and TEM analysis. Rhamnolipids chitosan nanoparticles (RLs-CS_p) presented the highest antimicrobial effect towards S. aureus (ATCC 25923) exhibiting a minimal inhibitory concentration of 130 μg/mL and a biofilm inhibition ability of 99 %. Additionally, RLs-CS_p did not interfere with human dermal fibroblasts (AG22719) viability and proliferation under the tested conditions. The results revealed that the RLs-CS_p were able to inhibit bacterial growth showing adequate cytocompatibility and might become, after additional studies, a valuable approach to prevent S. aureus related infections.

Synthesis of Ag@Au core-shell NPs loaded with Ciprofloxacin as enhanced antimicrobial properties for the treatment and nursing care of Escherichia coli infection

Bimetallic nanoparticles act as a multi-functional platform because of extraordinary properties that are most capable materials for biological applications. The present study reports the improvement of Au@ Ag-core shell nanoparticles filled in as seeds for ceaseless affidavit of silver molecules on its chitosan surface. The FT-IR spectrum techniques used to identify stretching vibrations of prepared NPs. The X-ray diffraction (XRD) outcomes show the medium crystalline shape and size of the Ag@Au loaded chitosan was around at 30 nm. The morphological structure of nanoparticles (NPs) was proved by Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). The Ag@Au contained chitosan results displayed the most elevated zone of hindrance 24 mm and lowest value 0.2 μg/mL of MIC against E. coli and treated with ciprofloxacin. The excellent antimicrobial results proven that the Ag@Au loaded chitosan can enhance the antibacterial activity. The combined Ag@Au core-shell NPs were intricately performed for cytotoxicity against human bosom malignant growth (MCF7) and cervical (HeLa) anticancer cell lines. The Ag@Au NPs may have incredible potential as viable antibacterial operators for pathogen control in clinics and nourishment preparing.