Characterization, Antioxidant and Antibacterial Potentials of Tamarindus indica L. Fruit Pulp Extract Loaded O/W Nanoemulsions

Abstract The main purposes of the current study were to formulate o/w nanoemulsions as a carrier for Tamarindus indica (tamarind) fruit pulp extract and to study the antioxidant and antibacterial potentials of nanoemulsions containing tamarind extract, focusing on cosmetic/hygiene applications. The o/w nanoemulsions using a mixture of Tween 80 and Span 80 as an emulsifier (5%w/w) were prepared by a high pressure homogenization process. Two concentrations of sweet tamarind extract, 3.3 and 6.6%w/w, based on the bioactivity study, were incorporated into the blank nanoemulsions to produce loaded nanoemulsions, F1-3.3TE (3.3%) and F1- 6.6TE (6.6%). As compared with the unloaded nanoemulsion, both tamarind extract loaded nanoemulsions showed reduced pH and significantly increased viscosity. Overall, the loaded nanoemulsions had droplet sizes of approximately 130 nm, zeta potential around -38 mV and polydispersity index (PDI) values less than 0.2. The nanoemulsion F1-3.3TE had better stability (e.g. significantly greater % tartaric acid content and lesser PDI value) than the nanoemulsion F1-6.6TE did. The antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl assay revealed that the nanoemulsions F1-3.3TE and F1-6.6TE had scavenging activities of 81.66 ± 0.77% and 63.80 ± 0.79%, respectively. However, antioxidant activity of these two formulations decreased under stress conditions (heating-cooling cycles). Such incidence did not occur for their antibacterial properties investigated by agar well diffusion technique. The two formulations exhibited inhibition zones of approximately 24.0-27.7 mm against Staphylococcus aureus and Staphylococcus epidermidis, responsible for malodor of underarms. The results suggest the potential of using sweet tamarind pulp extract loaded nanoemulsions as hygiene products.

Physical, chemical, and microbiological stability of extemporaneous furosemide suspensions.

Background: Furosemide is a potent diuretic used in treatment of oedematous states associated with cardiac, renal, and hepatic failure and the treatment of hypertension. In Thailand, no liquid formulation of furosemide is commercially available for pediatric administration and for adult who cannot swallow furosemide tablets. Objective: Prepare extemporaneous furosemide suspensions from commercial furosemide tablets using two compounded suspending vehicles, and determine the physical, chemical, and microbiological stability of these preparations. Methods: Two formulations of extemporaneous furosemide suspensions were prepared from commercially available furosemide 40-mg tablets using two compounded suspending vehicles. The final concentration of furosemide in each formulation was 2 mg/mL. Three samples of each formulation were stored in glass bottles protected from light, and kept at three controlled temperature, 4?2?C, room temperature (30?2?C), and 45?C. A sample was removed from each bottle immediately after preparation and at 7, 14, 30, 45, and 60 days. The stability-indicating highperformance liquid chromatography was used to analyze for furosemide. The pH was measured. The physical and microbiological properties of these formulations were evaluated after storage for two months. The stability of furosemide suspensions was determined by calculating the percentage of the initial concentration remaining on each test day. Stability was defined as retention of at least 90% of the initial concentration. Results: At least 93% of the initial furosemide concentration remained in both compounded furosemide suspensions for up to 60 days. There were no substantial changes in the appearance (color and consistency) or odor of both formulations. The pH values of both formulations kept at 4?2?C increased slightly, while the pH values of both formulations kept at 45?2?C decreased significantly compared with the initial pH value of both formulations. Both formulations maintained microbiologic stability for 60 days. Conclusion: Extemporaneously compounded furosemide suspensions, 2 mg/mL, were stable for at least 60 days when stored in glass bottles protected from light at three controlled temperatures. These compounded furosemide suspensions are better suited for administration to children and adults who cannot swallow furosemide tablets. They may provide an alternative in situations where the marketed suspension is unavailable.

Physicochemical properties, in vitro release and in vivo evaluation of tramadol hydrochloride rectal suppository and rectal gel.

Background: Tramadol is a centrally acting analgesic drug. Rectal administration of tramadol is useful in the treatment of post-operative pain or malignant pain in cases where it cannot be administered orally. In Thailand, tramadol is available only as a capsule for oral use and as a solution for injection. Objective: Develop tramadol hydrochloride rectal suppositories and rectal gel preparations. Methods: Tramadol rectal suppository and rectal gel were prepared. Physicochemical properties (viscosity, gel strength, mucoadhesive force) and the in vitro release of tramadol hydrochloride were investigated from different bases (Witepsol H15, polyethylene glycol, poloxamer, and hydroxyethylcellulose). The analgesic activity of rectal tramadol hydrochloride using the hot plate test was evaluated in rats. Results: Tramadol hydrochloride rectal gel using poloxamer was more mucoadhesive to the rectal mucous membrane than was the gel with the hydroxyethylcellulose base. Tramadol hydrochloride was released rapidly in vitro from both the Witepsol H15 and polyethylene glycol bases. It was completely released from the polyethylene glycol suppository base within 15 minutes. The amount of tramadol hydrochloride release from the Witepsol H15 suppository base was about 93% at 120 minutes. When using poloxamer or hydroxyethylcellulose as a rectal base, about 90% of the tramadol hydrochloride was released from both bases within 15 minutes and completely released within 30 minutes. Administration of a tramadol hydrochloride suppository in rats exhibited a more pronounced analgesic effect with the polyethylene glycol base than with the Witepsol H15-based suppositories. The rectal gel had a less pronounced analgesic effect when made with the hydroxyethylcellulose base than with the poloxamer base. Conclusion: Tramadol hydrochloride suppositories and rectal gels with different bases showed rapid and almost complete drug release from the bases, prolonging the latency of a nociceptive response in in vivo experiments.