Development of buccal tablets for curcumin using Anacardium occidentale gum

Understanding Mucosal Physiology and Rationale of Formulation Design for Improved Mucosal Immunity

The oral and nasal cavities serve as critical gateways for infectious pathogens, with microorganisms primarily gaining entry through these routes. Our first line of defense against these invaders is the mucosal membrane, a protective barrier that shields the body's internal systems from infection while also contributing to vital functions like air and nutrient intake. One of the key features of this mucosal barrier is its ability to protect the physiological system from pathogens. Additionally, mucosal tolerance plays a crucial role in maintaining homeostasis by regulating the pH and water balance within the body. Recognizing the importance of the mucosal barrier, researchers have developed various mucosal formulations to enhance the immune response. Mucosal vaccines, for example, deliver antigens directly to mucosal tissues, triggering local immune stimulation and ultimately inducing systemic immunity. Studies have shown that lipid-based formulations such as liposomes and virosomes can effectively elicit both local and systemic immune responses. Furthermore, mucoadhesive polymeric particles, with their prolonged delivery to target sites, have demonstrated an enhanced immune response. This Review delves into the critical role of material selection and delivery approaches in optimizing mucosal immunity.

A comprehensive review on pharmaceutical uses of plant-derived biopolysaccharides

Biopolysaccharides extracted from plants are mainly photosynthetic byproducts found in leaves, pods, stems, fruits, grains, seeds, corms, rhizomes, roots, bark exudates, and other plant parts. Recently, these plant-derived biopolysaccharides have received a great deal of attention as pharmaceutical excipients in a range of different dosage forms because of several key advantages, such as widespread accessibility from nature as plant-based sources are readily available, sustainable production, availability of easy and cost-effective extraction methodologies, aqueous solubility, swelling capability in the aqueous medium, non-toxicity, biodegradability, etc. The current review presents a comprehensive overview of the uses of plant-derived biopolysaccharides as effective pharmaceutical excipients in the formulations of different kinds of dosage forms, for example gels, pastes, films, emulsions, suspensions, capsules, tablets, nanoparticles, microparticles, beads, buccal formulations, transdermal formulations, ocular formulations, nasal formulations, etc.

High-Payload Buccal Delivery System of Amorphous Curcumin-Chitosan Nanoparticle Complex in Hydroxypropyl Methylcellulose and Starch Films

Oral delivery of curcumin (CUR) has limited effectiveness due to CUR’s poor systemic bioavailability caused by its first-pass metabolism and low solubility. Buccal delivery of CUR nanoparticles can address the poor bioavailability issue by virtue of avoidance of first-pass metabolism and solubility enhancement afforded by CUR nanoparticles. Buccal film delivery of drug nanoparticles, nevertheless, has been limited to low drug payload. Herein, we evaluated the feasibilities of three mucoadhesive polysaccharides, i.e., hydroxypropyl methylcellulose (HPMC), starch, and hydroxypropyl starch as buccal films of amorphous CUR–chitosan nanoplex at high CUR payload. Both HPMC and starch films could accommodate high CUR payload without adverse effects on the films’ characteristics. Starch films exhibited far superior CUR release profiles at high CUR payload as the faster disintegration time of starch films lowered the precipitation propensity of the highly supersaturated CUR concentration generated by the nanoplex. Compared to unmodified starch, hydroxypropyl starch films exhibited superior CUR release, with sustained release of nearly 100% of the CUR payload in 4 h. Hydroxypropyl starch films also exhibited good payload uniformity, minimal weight/thickness variations, high folding endurance, and good long-term storage stability. The present results established hydroxypropyl starch as the suitable mucoadhesive polysaccharide for high-payload buccal film applications.

Mucoadhesive Delivery System: A Smart Way to Improve Bioavailability of Nutraceuticals

The conventional oral administration of many nutraceuticals exhibits poor oral bioavailability due to the harsh gastric conditions and first-pass metabolism. Oral mucosa has been recognized as a potential site for the delivery of therapeutic compounds. The mucoadhesive formulation can adhere to the mucosal membrane through various interaction mechanisms and enhance the retention and permeability of bioactive compounds. Absorption of bioactive compounds from the mucosa can improve bioavailability, as this route bypasses the hepatic first-pass metabolism and transit through the gastrointestinal tract. The mucosal administration is convenient, simple to access, and reported for increasing the bioactive concentration in plasma. Many mucoadhesive polymers, emulsifiers, thickeners used for the pharmaceutical formulation are accepted in the food sector. Introducing mucoadhesive formulations specific to the nutraceutical sector will be a game-changer as we are still looking for different ways to improve the bioavailability of many bioactive compounds. This article describes the overview of buccal mucosa, the concept of mucoadhesion and related theories, and different techniques of mucoadhesive formulations. Finally, the classification of mucoadhesive polymers and the mucoadhesive systems designed for the effective delivery of bioactive compounds are presented.

Development of purified cashew gum mucoadhesive buccal tablets containing nystatin for treatment of oral candidiasis

OBJECTIVE

The objective of this work was to prepare mucoadhesive buccal tablets containing nystatin and purified cashew gum for the treatment of oral candidiasis.

SIGNIFICANCE

Mucoadhesive buccal tablets containing the drug nystatin are an alternative to oral suspensions, which cause low therapeutic adherence to the treatment of oral candidiasis. Purified cashew gum has been studied as a diluent and mucoadhesive agent in tablets.

METHODS

Two batches of mucoadhesive tablets were produced, MT1 and MT 2, containing purified cashew gum, nystatin (500,000 IU), flavoring agent and with or without the presence of lubricant agent. The average weight, mechanical properties, dose uniformity, drug release profile, mucoadhesive properties and antimicrobial activity against Candida albicans were evaluated.

RESULTS

Tablets presented average weight of 329.1 ± 3.1 mg (MT1) and 334.6 ± 1.5 mg (MT2), hardness of 9.8 ± 0.8 KgF (MT1) and 8.3 ± 0.4 KgF (MT2), friability of 0.2% (MT1 and MT2), and dose uniformity of 102.20 ± 1.17% (MT1) and 99.06 ± 7.40% (MT2). MT1 and MT2 were able to swell, erode, release the drug and remain adhered to the pig's cheek up to 3 h for batch MT1 and 4 h for batch MT2, and the amount of nystatin released since the beginning of the test in both batches was sufficient to inhibit the growth of the fungus.

CONCLUSIONS

Therefore, the proposed formulation proved to be very promising and met all the studied criteria, showing to be ideal for the treatment of oral candidiasis.

In vivo approach of simply constructed pyrazinamide conjugated chitosan-g-polycaprolactone micelles for methicillin resistance Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is an extensive origin of nosocomial infections that are very much challenging as well as complicated to eradicate mostly due to their strong resistance against all existing antibiotic therapies. Here the chitosan-grafted-polycaprolactone/maleic anhydride-pyrazinamide (CS-g-PCL/MA-PZA) polymeric drug carrier constructed via dialysis for anti-MRSA drugs like rifampicin (RF) and pyrazinamide (PZA) delivery. Nearly 200 nm size of the spherical particle with -20.04 mV of zeta potential observed. The cumulative PZA and RF releases from the carrier were observed 83.25% and 76.54% respectively in pH 5.5, and the in vitro drug release profile demonstrates that the fabricated micelle was pH-responsive. For the intestinal colonization, an in vivo assay performed using C. elegans, and the CS-g-PCL/MA-PZA/RF micelles treated worms generally belong to the weakly colonized category. Therefore, the study revealed that CS-g-PCL/MA-PZA/RF micelle could be a promising approach for therapeutic applications to achieve efficient anti-MRSA drug delivery.

Antibacterial activity of irradiated extracts of Anacardium occidentale L. on multiresistant strains of Staphylococcus aureus

This study evaluated the antibacterial activity of crude and fractionated leaf extracts of Anacardium occidentale, after receiving 10 kGy from ⁶⁰Co, against multiresistant strains of Staphylococcus aureus in vitro. Minimum Inhibitory Concentrations-MIC and Minimum Bacteriostatic Concentrations-MBC were respectively assessed by serial microdilution technique in multiwall plates and Petri dishes, against standard strains and clinical isolates of multiresistant S. aureus. The results pointed out a significantly increase of the antibacterial activity of the such extracts after irradiation, emphasizing the role of gamma radiation on leaf extracts of A. occidentale to improve bioactive substances, offering new raw material for antibacterial drugs.

Effect of dynamic high pressure on emulsifying and encapsulant properties of cashew tree gum

Dynamic high pressure (DHP) has been applied in the physical modification of biopolymers as polysaccharides, proteins and gums. It is known that DHP is able to promote degradation of polysaccharides (e.g. molecular weight reduction). However, few studies have assessed the effect of DHP on the emulsifying and encapsulating properties of polysaccharides. Thus, this study aimed to investigate the effect of DHP on the emulsifying (average droplet size and particle size distribution, optical and confocal scanning laser microscopy, rheology, zeta potential and electric conductivity, creaming index, and turbidity) and encapsulating (scanning electronic microscopy, flavor retention, average droplet size, and particle size distribution) properties of cashew tree gum (CG). The application of DHP process improved the emulsifying capacity of cashew tree gum (CG) by reducing the medium droplet size (D3,2 and D4,3), increasing the turbidity and improving the emulsion stability. However, no effect of DHP was observed on the encapsulating capacity of CG.

In Vitro and Ex Vivo Evaluation of Novel Curcumin-Loaded Excipient for Buccal Delivery

This study aimed to develop a mucoadhesive polymeric excipient comprising curcumin for buccal delivery. Curcumin encompasses broad range of benefits such as antioxidant, anti-inflammatory, and chemotherapeutic activity. Hyaluronic acid (HA) as polymeric excipient was modified by immobilization of thiol bearing ligands. L-Cysteine (SH) ethyl ester was covalently attached via amide bond formation between cysteine and the carboxylic moiety of hyaluronic acid. Succeeded synthesis was proved by H-NMR and IR spectra. The obtained thiolated polymer hyaluronic acid ethyl ester (HA-SH) was evaluated in terms of stability, safety, mucoadhesiveness, drug release, and permeation-enhancing properties. HA-SH showed 2.75-fold higher swelling capacity over time in comparison to unmodified polymer. Furthermore, mucoadhesion increased 3.4-fold in case of HA-SH and drug release was increased 1.6-fold versus HA control, respectively. Curcumin-loaded HA-SH exhibits a 4.4-fold higher permeation compared with respective HA. Taking these outcomes in consideration, novel curcumin-loaded excipient, namely thiolated hyaluronic acid ethyl ester appears as promising tool for pharyngeal diseases.

Gums' based delivery systems: Review on cashew gum and its derivatives

The development of delivery systems using natural polymers such as gums offers distinct advantages, such as, biocompatibility, biodegradability, and cost effectiveness. Cashew gum (CG) has rheological and mucoadhesive properties that can find many applications, among which the design of delivery systems for drugs and other actives such as larvicide compounds. In this review CG is characterized from its source through to the process of purification and chemical modification highlighting its physicochemical properties and discussing its potential either for micro and nanoparticulate delivery systems. Chemical modifications of CG increase its reactivity towards the design of delivery systems, which provide a sustained release effect for larvicide compounds. The purification and, the consequent characterization of CG either original or modified are of utmost importance and is still a continuing challenge when selecting the suitable CG derivative for the delivery of larvicide compounds.

Design and optimization of clotrimazole–hydroxypropyl-β-cyclodextrin bioadhesive vaginal tablets using Anacardium occidentale gum by 32 factorial design

Clotrimazole (CTZ), a BCS class II drug, is widely employed in the treatment of vaginal candidiasis.

Intranasal therapeutic strategies for management of Alzheimer's disease

Alzheimer's disease (AD) is a chronic and progressive age-related irreversible neurodegenerative disorder that represents 70% of all dementia with 35 million cases worldwide. Successful treatment strategies for AD have so far been limited, and present therapy is based on cholinergic replacement therapy and inhibiting glutamate excitotoxicity. In this context, role of neuroprotective drugs has generated considerable interest in management of AD. Recently, direct intranasal (IN) delivery of drug moieties to the central nervous system (CNS) has emerged as a therapeutically viable alternative to oral and parenteral routes. IN delivery bypasses the blood-brain barrier by delivering and targeting drugs to the CNS along the olfactory and trigeminal neural pathways which are in direct contact with both the environment and the CNS. In an attempt to understand how neurotherapeutics/nanoparticulate delivery systems can be transported from the nose to the CNS, the present review sets out to discuss the mechanism of transport from nose to brain. The aim of this review is to discuss and summarize the latest findings of some of the major studies on IN drug delivery in AD models, with a focus on the potential efficacy of neuroprotective treatments.

Optimization of curcumin nanoemulsion for intranasal delivery using design of experiment and its toxicity assessment

The objective of the study was to optimize curcumin nanoemulsion for intranasal delivery using design of experiment. Box-Behnken design was constructed using oil, surfactant and co-surfactant concentration as independent variables and their affect on response y1 (globule size) and y2 (zeta potential) were studied. The ANOVA test identified the significant factors that affected the responses. For globule size, percentage of oil, surfactant and co-surfactant were identified as significant model terms whereas for zeta potential, oil and co-surfactant were found to be significant. Critical factors affecting the responses were identified using perturbation and contour plots. The derived polynomial equation and contour graph aid in predicting the values of selected independent variables for preparation of optimum nanoemulsion with desired properties. Further, 2(4) factorial design was used to study influence of chitosan on particle size and zeta potential. The formulations were subjected to in vitro cytotoxicity using SK-N-SH cell line and nasal ciliotoxicity studies. The developed formulations did not show any toxicity and were safe for intranasal delivery for brain targeting. In vitro diffusion studies revealed that nanoemulsions had a significantly higher release compared to drug solution. Ex vivo diffusion studies were carried out using sheep nasal mucosa fixed onto Franz diffusion cells. Mucoadhesive nanoemulsion showed higher flux and permeation across sheep nasal mucosa.

Physicochemical characterization and toxicological evaluation of plant-based anionic polymers and their nanoparticulated system for ocular delivery

The water-soluble fractions of mucilages and gum from the seeds of fenugreek, isphagula and mango bark exudate were isolated, purified and characterized using X-ray diffraction (XRD) spectrometry, Fourier transform infrared spectroscopy (FT-IR), maldi/GC-MS, elemental analysis, 1D ((1)H and (13)C) and 2D (HMQC, COSY) nuclear magnetic resonance spectroscopy (NMR). The fenugreek mucilage was identified to be a galactomannan chain consisting of 4 units of galactose attached to the backbone of 6 mannose units in 1:1.5 ratio. The isphagula mucilage was identified to be an arabinoxylan polysaccharide chain consisting of 4 units of arabinofuranose attached to the backbone of 9 xylopyrannose units in 1:3 ratio. The mango gum showed the presence of amylose, α-arabinofuranosyl and β-galactopyranosyl, respectively. The characterized mucilages and gum were individually formulated into nanoparticulate system using their complementarily charged polymer chitosan. The particles were observed to be spherical in shape in the range of 61.5-90 nm having zetapotential between 31 and 34 mV and PDI of 0.097-0.241. The prepared nanoparticles were observed to be nonirritant and nontoxic in vitro and in vivo upto 2000 μg/ml. Therefore, these mucilages and gum can be the alternatives of anionic polymers for the ocular drug delivery system.