Hydrogel Formulation of Usnic Acid and Antibacterial Activity Test Against Propionibacterium acne

Abstract

Usnic acid is known for its remarkable antimicrobial activity. The aim of this research was to formulate hydrogel of usnic acid and evaluate the antibacterial activity against Propionibacterium acne. Due to low solubility of usnic acid, solid dispersion was prepared using PVP K-30. In this study, intact usnic acid (UA) and usnic acid-solid dispersion (UA-SD) was formulated in hydrogel using several gelling agents: Aqupec HV-505, sodium alginate and HPMC K 100M. Concentration of each gelling agent was optimized for hydrogel base. All of hydrogel base showed homogenous gel, pH at range 5.37-6.33 and viscosity in range 259.07-10,759.00 cps. Hydrogel was prepared by dispersing 1% intact UA and 3% UA-SD in three different gelling agents. The hydrogel was evaluated for pH, viscosity, stability test for two months and microbiology test. The amount of usnic acid in hydrogel was determined by spectrophotometry UV-Vis. Hydrogel UA showed non-homogenous gel, while hydrogel usnic UA-SD was homogenous. The pH of all hydrogel was in range 5.5-6.4 and viscosity was 2,017.03-3,866.52 cps. All the hydrogel was stable and diameter inhibition of hydrogel was in a range 20-32 mm. The amount of usnic acid in hydrogel was in range 96.9-99.23%. In conclusion, hydrogel UA-SD is promising preparation in handling acne.

Enhancement of α-Mangostin Wound Healing Ability by Complexation with 2-Hydroxypropyl-β-Cyclodextrin in Hydrogel Formulation

“…The presence of water in HG allows α-M ionization to liberate a hydrogen ion, underlying the pH decrease of the HG. Although the pH of the preparations decreased on the 7th day, all the preparation were stable until 14 days in the skin pH range (4.5–6.5) [ 30 , 31 ].…”

“…Briefly, 1% of each sample (α-M HG, α-M/HP-β-CD CX HG, and α-M/HP-β-CD PM HG) was diluted with 20 mL of distilled water in a 25 mL glass beaker, and then the pH was measured using a pH meter. The pH should have been in the range of 4.5–6.5 [ 30 , 31 ].…”

“…A weight of 150 g was added above the upper dish for 5 min, and the final diameter was measured. The diameter of the spreadability area should have been in the range of 5–7 cm [ 31 , 48 , 51 ].…”

Body scrub virgin coconut oil (vco), coffee grounds (coffea arabika linn.) and carbon active coconut shell (activated carbon coconut nucifera l) as a moisturizer and skin lightening

“…A load of 150 g is given for 1 minute at 25 ° C, after which the diameter of the spread is measured. The diameter of the dispersive power should be in the range 3-5 cm (Fitriani et al, 2018).…”

“…1 gram sample is dissolved in 100 mL aquadest. The acceptable pH is in the range 4.5-6.5 (Fitriani et al, 2018).…”