FORMULATION OF SUNFLOWER OIL (HELIANTHUS ANNUUS L.) LIQUID CRYSTAL NANOEMULSION CONTAINING ALPHA-TOCOPHERYL ACETATE AND PHYSICAL STABILITY EVALUATION AGAINST TEMPERATURE DIFFERENCES

• Main Author: Hasya Nisa, Zahira
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/78421
• Institution: Institut Teknologi Bandung

Antioxidants are compounds that can stabilize free radicals so that they can overcome premature aging due to ultraviolet radiation. One compound that has antioxidant activity is alpha-tocopheryl acetate (vitamin E). This study aims to determine the optimum formulation and evaluate the physical stability of liquid crystal nanoemulsion preparations. The research was conducted in several stages: preliminary testing, optimization, characterization, and evaluation. The preliminary test was carried out by screening surfactants and determining the solubility of the active substance. Optimization of oil concentration factors and procedures are optimized using the OFAT (One Factor at a Time) method. The preparations were made using high-shear homogenization and ultrasonication methods. Formula optimization using the Box Behnken method, with independent variables in the form of the ratio of surfactant concentrations of tween 80 and cetostearyl alcohol with a ratio of 1:7-7:1, the concentration of the total surfactant mixture is 3-5%, and the concentration of propylene glycol is 1-3%. The optimum formula was characterized in terms of organoleptic properties, particle size, polydispersity index, zeta potential, microscopic observation, alpha-tocopheryl acetate content, encapsulation efficiency, pH, occlusive factor, physical stability, and antioxidant activity. Optimization results were analyzed using the Minitab application. The optimum formula obtained consisted of 4% (w/v) sunflower oil, 1% (w/v) alpha-tocopherol acetate, 0.66% (w/v) propylene glycol, 0.5% (w/v) phenoxyethanol, with a total surfactant concentration of 3.8% in a ratio of 7:1 (tween 80:cetostearyl alcohol). The final preparation is white, odorless, with a liquid consistency, there is a liquid crystal form that is clearly observed under a microscope, has a particle size of 206.50 ± 2.85 nm, polydispersity index of 0.38 ± 0.09, pH of the preparation is 6, 17 ± 0.14, zeta potential -35,40 ± 1,16 mV, alpha-tocopherol acetate content 98.43% (w/v), encapsulation efficiency above 95%, occlusive factor 30.60 ± 1.83%. The nanoemulsion preparations were physically stable at 4, 25, and 40 ?C for 28 days, supported by stability tests using centrifugation and freeze-thaw methods. The antioxidant activity of alpha-tocopherol acetate, base, and optimum nanoemulsion formula were 16.97 ± 1.3, 0.61 ± 0.16, and 3.36 ± 0.13 mg AEAC/g, respectively.