Physicochemical Characterization and Evaluation of Ficus vasta Gum as a Binder in Tablet Formulation

Binders are ingredients used in tablet granulation process for tablet cohesiveness which confirms that the tablet remains intact after compression. Natural gums have been employed as disintegrants, emulsifying agents, suspending agents, and binders in tablets. Even though Ficus vasta gum is claimed as a possible pharmaceutical excipient by some phytochemical studies, literature is scanty on its efficacy as a tablet binder. The purpose of this study was to isolate, characterize, and comparatively evaluate Ficus vasta gum as a potential binder in tablet formulation. Gum was extracted from Ficus vasta tree, characterized for physicochemical properties, and applied as a binder in paracetamol granule and tablet formulation. Granules were prepared using 4%, 6%, 8%, and 10% w/w concentration of the gum and standard binders (polyvinylpyrrolidone K-30 and Starch@1500) by wet granulation. The formulated tablets were then evaluated for tablet quality parameters, and comparison between the test and standard binders was done by ANOVA. The dried crude gum yielded 50.63% (w/w) of a brownish yellow purified gum. The angle of repose, Carr's index, and the Hausner ratio all complied with the pharmacopoeial recommendations. The gum is compatible with the model drug, paracetamol. The paracetamol granules prepared with Ficus gum binder demonstrated an optimum size range and size distribution with substantial flow and compressibility properties. Ficus gum binder demonstrated significantly higher disintegration time and strength properties than that of similar concentrations of Starch@1500 but lower than polyvinylpyrrolidone (p < 0.05). Ficus gum has better binding properties than starch but lower than polyvinylpyrrolidone. Hence, Ficus vasta gum can be used as an alternative tablet binder in tablet manufacturing.

Physicochemical and Microbiological Characteristics of Stem Bark Exudate Gum of Cordia millenii Tree in Conventional Release Tablets

The development of a raw material into an acceptable pharmaceutical excipient involves evaluation of the physicochemical and formulation properties of the potential raw material. Results from these evaluations may serve as a guide to subsequent use of the substance. The objective of the study was to evaluate the physicochemical and microbiological properties of the stem bark gum of Cordia millenii tree in conventional release paracetamol tablets. From the physicochemical evaluations, the gum was slightly acidic and soluble in all the aqueous-based solvents, except 0.1 N HCl in which it was sparingly soluble. All the absorptive properties of the gum indicated tablet disintegrating potential for tablet formulation. The total ash of the gum was higher than that of the international standard gum arabic. Micromeritic properties of the gum indicated the need for a flow aid to improve its flowability. There were no harmful microorganisms detected in the gum. Aerobic organisms and moulds and yeast were detected within permissible limits. Tablets formulated using six different concentrations of gum dispersions as a binder were generally soft and failed the USP T₈₀ standard of dissolution, indicating poor binding and drug releasing properties. Quality control properties of three different batches of tablets containing varying concentrations of the dry gum as a disintegrating agent were comparable to tablets containing equal concentrations of corn starch. The in vitro drug releases were similar at all-time points of drug evaluation. The gum can therefore be considered as a good disintegrant in the formulation of conventional release tablets.

Determination of Temperature-Dependent Coefficients of Viscosity and Surface Tension of Tamarind Seeds (Tamarindus indica L.) Polymer

The rheological properties of tamarind seed polymer are characterized for its possible commercialization in the food and pharmaceutical industry. Seed polymer was extracted using water as a solvent and ethyl alcohol as a precipitating agent. The temperature’s effect on the rheological behavior of the polymeric solution was studied. In addition to this, the temperature coefficient, viscosity, surface tension, activation energy, Gibbs free energy, Reynolds number, and entropy of fusion were calculated by using the Arrhenius, Gibbs–Helmholtz, Frenkel–Eyring, and Eotvos equations, respectively. The activation energy of the gum was found to be 20.46 ± 1.06 kJ/mol. Changes in entropy and enthalpy were found to be 23.66 ± 0.97 and −0.10 ± 0.01 kJ/mol, respectively. The calculated amount of entropy of fusion was found to be 0.88 kJ/mol. A considerable decrease in apparent viscosity and surface tension was produced when the temperature was raised. The present study concludes that the tamarind seed polymer solution is less sensitive to temperature change in comparison to Albzia lebbac gum, Ficus glumosa gum and A. marcocarpa gum. This study also concludes that the attainment of the transition state of viscous flow for tamarind seed gum is accompanied by bond breaking. The excellent physicochemical properties of tamarind seed polymers make them promising excipients for future drug formulation and make their application in the food and cosmetics industry possible.

Synthesis and Rheological Survey of Xanthan Gum Based Terpolymeric Hydrogels

Graft copolymerization technique was used to synthesize novel biopolymer based terpolymeric hydrogels of xanthan gum (Gx), acrylic acid and N-Isopropyl acrylamide (NIPAM) by using chemical crosslinker N,N′-methylene bisacrylamide (MBA), ammonium persulphate (APS) as a redox initiator and sodium dodecyl sulphate (SDS) for particle size stabilization. The synthesized hydrogels were characterized through FT-IR and SEM techniques, which confirmed the hydrogels formation. Detailed rheology was investigated through applying various rheological models like Bingham model, modified Bingham model and Ostwald power law model to the hydrogels which revealed that the hydrogels were appeared to have shear thinning, non-Newtonian behavior and more elastic. Modified Bingham model provided best fit understanding to our prepared materials. The maximum activation energy (Ea) 13.87 kJ/mol was obtained for composition having more Gx compared to others, showing a strong relationship with viscosity. The hydrogels has potential to find applications in food industry, cosmetics, degradation of dyes and removal of heavy metals from waste water.

Yield, Esterification Degree and Molecular Weight Evaluation of Pectins Isolated from Orange and Grapefruit Peels under Different Conditions

Orange (Citrus sinensis) and grapefruit (Citrus paradise) peels were used as a source of pectin, which was extracted under different conditions. The peels are used under two states: fresh and residual (after essential oil extraction). Organic acid (citric acid) and mineral acid (sulfuric acid) were used in the pectin extraction. The aim of this study is the evaluation the effect of extraction conditions on pectin yield, degree of esterification “DE” and on molecular weight “Mw”. Results showed that the pectin yield was higher using the residual peels. Moreover, both peels allow the obtainment of a high methoxyl pectin with DE >50%. The molecular weight was calculated using Mark-Houwink-Sakurada equation which describes its relationship with intrinsic viscosity. This later was determined using four equations; Huggins equation, kramer, Schulz-Blaschke and Martin equation. The molecular weight varied from 1.538 x10⁰⁵ to 2.47x10⁰⁵ g/mol for grapefruit pectin and from 1.639 x10⁰⁵ to 2.471 x10⁰⁵ g/mol for orange pectin.

Theoretical and experimental studies on the corrosion inhibition potentials of some purines for aluminum in 0.1 M HCl

Experimental aspect of the corrosion inhibition potential of adenine (AD), guanine (GU) and, hypoxanthine (HYP) was carried out using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods while the theoretical aspect of the work was carried out by calculations of semi-empirical parameters (for AM1, MNDO, CNDO, PM3 and RM1 Hamiltonians), Fukui functions and inhibitor–metal interaction energies. Results obtained from the experimental studies were in good agreement and indicated that adenine (AD), guanine (GU) and hypoxanthine (HYP) are good adsorption inhibitors for the corrosion of aluminum in solutions of HCl. Data obtained from electrochemical experiment revealed that the studied purines functioned by adsorption on the aluminum/HCl interface and inhibited the cathodic half reaction to a greater extent and anodic half reaction to a lesser extent. The adsorption of the purines on the metal surface was found to be exothermic and spontaneous. Deviation of the adsorption characteristics of the studied purines from the Langmuir adsorption model was compensated by the fitness of Flory Huggins and El Awardy et al. adsorption models. Quantum chemical studies revealed that the experimental inhibition efficiencies of the studied purines are functions of some quantum chemical parameters including total energy of the molecules (TE), energy gap (E_L–H), electronic energy of the molecule (EE), dipole moment and core–core repulsion energy (CCR). Fukui functions analysis through DFT and MP2 theories indicated slight complications and unphysical results. However, results obtained from calculated Huckel charges, molecular orbital and interaction energies, the adsorption of the inhibitors proceeded through the imine nitrogen (N5) in GU, emanine nitrogen (N7) in AD and the pyridine nitrogen (N5) in HPY.