Drug delivery applications and future prospects of microbial exopolysaccharides.

Over the years, exopolysaccharides (EPSs) have been utilized in various areas of research, including health, industry, environment, and agriculture, due to their flexible physical, chemical and structural properties that can be readily modified to suit desired purposes. Current research trends have shown that EPS production is dependent on numerous factors which can be combined to varying extent to optimize production yields. Although the majority of research is directed towards their industrial and medicinal uses, these chemical substances possess peculiar characteristics which are also exploited for biomedical research, where they are being used as drug delivery systems, some of which include their abundance in nature, biocompatibility, biodegradability, non-toxicity, and ability to efficiently encapsulate sensitive bioactive agents.

Utilisation of plant extracts and parts in antimicrobial formulations and as a pharmaceutical excipient: a review.

Background: Antimicrobial resistance and the environmental threat posed by some synthetic antimicrobial agents necessitate more research into development of novel pharmaceutical products that are environmentally friendly. Also, the use of plant derived excipients is growing and opening up new avenue to solve current drug delivery issues in the pharmaceutical industry.

Main Body: This review summarizes studies related to the antimicrobial property of extracts, possible mechanisms of antimicrobial action and antimicrobial formulations from the plant and overview of researches relating to the use of as a pharmaceutical excipient.

Design and evaluation of the antimicrobial properties of ackee seed extract silver nanoparticle film formulations.

Background: Plant-extract-reduced metal nanoparticles provide means of overcoming microbial resistance. Incorporating them into appropriate pharmaceutical formulations will enhance their portability and ease of administration.

Objectives: To synthesize silver nanoparticles using methanol extracts of the seeds of Blighia sapida as capping agents and formulating the products in antimicrobial films.

Microsphere formulations of ambroxol hydrochloride: influence of Okra (Abelmoschus esculentus) mucilage as a sustained release polymer.

Ambroxol hydrochloride (AH), a secretion-releasing expectorant, is a good candidate for sustained delivery. Mucilages are biodegradable, inexpensive carriers in microsphere formulations. The study aimed to prepare microspheres of AH using Okra mucilage obtained from pods of Abelmoschus esculentus combined with sodium alginate at various polymer/drug ratios.

Evaluation of mucoadhesive property and the effect of gum on intranasal vaccination against small ruminant morbillivirus infection (PPR).

A study was conducted to evaluate mucoadhesive property and immunomodulatory effect of phytogenic gums from and on intranasal Peste des petits ruminants (PPR) vaccination in goats and sheep in an ex-vivo and in-vivo situations. Plant gums were purified, dried and compressed into 500gm tablets. Modified shear stress measurement technique was used on freshly excised trachea and intestine tissues of goat to measure peak adhesion time.

Starch nanoparticles in drug delivery: A review.

The uptake and specificity of drugs and the bioavailability of poorly soluble drugs has been improved by means of targeted drug delivery using nanoparticles. Many platforms have been used for nanoparticulate drug delivery and these include liposomes, polymer conjugates, metallic nanoparticles, polymeric micelles, dendrimers, nanoshells, and protein and nucleic acid-based nanoparticles. Starch is the 2nd most abundant natural polymer and has found wide use in drug delivery systems as binder, disintegrant and filler.

Clinicopathological evaluation of Newcastle disease virus vaccination using gums from and as delivery agents in challenged chickens.

Following previous studies on delivery potential and immune response of chickens given Newcastle disease vaccine with gums, this study was conducted to evaluate the protective ability of vaccines delivered with plant gums against clinicopathological features of Newcastle disease (ND). Processed gums from incised trunks of and trees were combined with ND vaccine in ratio 2:2:1 and administered at 21 days to white leghorn cockerels after weaning of maternal antibodies. The birds were grouped into gum-vaccine-oral (GVOR), vaccine-oral (VOR), gum-vaccine-ocular (GVOC), vaccine-ocular (VOC), gum-oral (GOR), gum-ocular (GOC), no-gum-no-vaccine/challenged (NGNV/C), no-gum-no-vaccine/unchallenged (NGNV/U).

Native and microwave-modified Terminalia mantaly gums as sustained-release and bioadhesive excipients in naproxen matrix tablet formulations.

Background: Hydrophilic polymers provide a means of sustaining drug delivery. Native gums may be limited in function, but modification may improve their activity.

Objectives: The aim of the study was to evaluate native and modified forms of Terminalia mantaly gum for their sustained-release and bioadhesive properties.

Evaluation of two novel plant gums for bioadhesive microsphere and sustained-release formulations of metformin hydrochloride.

Background: The biological half life of metformin requires multiple doses which are associated with poor patient compliance. This justifies the need for a dosage form with reduced dosing frequency.

Objectives: Gums from Enterolobium cyclocarpum and Cedrela odorata trees were evaluated in formulating bioadhesive microspheres containing metformin hydrochloride, for sustained drug release.

Ex-vivo evaluation of the mucoadhesive properties of Cedrela odorata and Khaya senegalensis gums with possible applications for veterinary vaccine delivery.

Background: Few studies have investigated the interaction of bioadhesives with biologic tissues for veterinary application. Hence, this study evaluates the mucoadhesive property and vaccine delivery properties of polymers from phytogenic origin. Gums from Cedrela odorata and Khaya senegalensis were harvested, purified, dried and compressed into 500 mg tablets individually and in combined ratios.

Formulation and Evaluation of Oral Dissolving Films of Amlodipine Besylate Using Blends of Starches With Hydroxypropyl Methyl Cellulose.

Background: Natural polymers serve as cheap, non-toxic, biocompatible excipients in oral drug delivery. These advantages inform their uses in the design of drug dosage forms.

Objectives: The aim of the study was to prepare and evaluate oral dissolving films of amlodipine besylate, an anti-hypertensive drug, using starch/polymer blends.

Material and Compression Properties of Cedrela odorata Gum Co-Processed with Plantain Starch and Microcrystalline Cellulose.

Background: Many excipients used in tableting exhibit some undesirable properties such as poor flow, cohesion and lubricating characteristics, thus necessitating some modification to achieve the desired product.

Objectives: The objective of this study was to enhance the material, flow and compressional properties of Cedrela odorata gum (COG) (Family: Meliaceae) by co-processing with plantain starch (PS) and microcrystalline cellulose (MCC).

Material And Methods: The COG was co-processed with PS (or MCC) by physical co-grinding at ratio 1 : 1, 1 : 2 and 1 : 4, and characterized using morphological analysis, swelling index viscosity measurements, particle size analysis and FTIR spectra.

EFFECT OF FORMULATION AND PROCESS VARIABLES ON THE RELEASE, MECHANICAL AND MUCOADHESIVE PROPERTIES OF IBUPROFEN TABLET FORMULATIONS.

A 2(4) full factorial analysis was used to study the individual and interactive effects of binder type, X1; binder concentration, X2; relative density, X3 and tabletting technique, X4, on disintegration time (DT), brittle fracture index (BFI), tensile strength (TS) and mucoadhesion time (MT) of ibuprofen tablets formulated by direct compression (DC) and wet granulation (WG), and containing Entandophragnia angolense gum (ENTA) as binder, in comparison with hydroxypropylcellulose. The result of the FTIR and UV peaks suggests the absence of any interaction between ENTA and ibuprofen. Interactions between the polymers and ibuprofen were determined using FTIR and UV determinations.

RELEASE AND MUCOADHESION PROPERTIES OF DICLOFENAC MATRIX TABLETS FROM NATURAL AND SYNTHETIC POLYMER BLENDS.

The delayed release and mucoadhesive properties of Cedrela gum and hydroxypropylmethylcellulose blend in diclofenac sodium tablet formulations were evaluated. Tablets were prepared by direct compression and the crushing strength and detachment force were found to increase from 74.49 ± 1.

The effect of processing variables on the mechanical and release properties of tramadol matrix tablets incorporating Cissus populnea gum as controlled release excipient.

Background: Natural gums are polymers widely used as excipients in drug formulation. Polymer extraction and formulation processing methods could significantly affect formulation characteristics.

Objectives: To evaluate different methods of gum extraction and the effect of different compression methods on the mechanical and release properties of tramadol hydrochloride matrix tablets incorporating cissus gum as controlled release polymer.

In vitro and in vivo antimicrobial evaluation of alkaloidal extracts of Enantia chlorantha stem bark and their formulated ointments.

The in vitro and in vivo antimicrobial evaluation of the formulated ointment of alkaloidal extract of Enantia chlorantha Oliv. (Annonaceae) was the concern of this study. The alkaloidal fraction of the stem bark extract was formulated into simple ointment using British Pharmacopoeia formula for preparation of simple ointment.

Effects of modification and incorporation techniques on disintegrant properties of wheat (Triticum aestivum) starch in metronidazole tablet formulations.

Background: Natural polymers serve as cheap, non-toxic, biocompatible excipients in drug delivery.

Objectives: Starch from wheat (Triticum aestivum) was investigated as a disintegrant in metronidazole tablet formulations in comparison with sodium starch glycolate (SSG), a standard, synthetic but relatively more expensive disintegrant.

Material And Methods: Native wheat starch (NAS) was modified by pregelatinization (PGS) and microwave irradiation (MCW).

Application of freeze-drying technology in manufacturing orally disintegrating films.

Freeze drying technology has not been maximized and reported in manufacturing orally disintegrating films. The aim of this study was to explore the freeze drying technology in the formulation of sildenafil orally disintegrating films and compare the physical properties with heat-dried orally disintegrating film. Central composite design was used to investigate the effects of three factors, namely concentration of carbopol, wheat starch and polyethylene glycol 400 on the tensile strength and disintegration time of the film.

Effects of excipients and formulation types on compressional properties of diclofenac.

Different models used to characterize powders have not been extended to granule behavior in tablet technology. Hence, Kawakaita equation and tapping experiments were used to compare the effect of different excipients on the properties of powders and granules in diclofenac formulations containing corn starch (DCS), lactose (DL) and dicalcium phosphate (DDCP). The binding properties of Albizia gum from Albizia zygia tree were also compared with those of gelatin in the granule formulations.